Replacement Of Co Research Articles

Butterfly-Fat-Tree topology based fault-tolerant Network-on-Chip design using particle swarm optimisation

ABSTRACTAs the technology is scaling down more number of processing elements are integrated on to a single chip, namely system-on-chips (SoCs). Using traditional bus architecture in SoCs, communication among different processing elements is difficult. Hence, to overcome it, a new on-chip interconnection paradigm known as network-on-chip (NoC) has been proposed. The communication among different processing elements in NoCs is achieved using packet switching technique. In nano-scale era, NoCs are prone to vulnerable faults and designing an NoC to meet current application requirements is highly challenging. Hence, there is a need to develop reliable and efficient Fault-tolerant NoC designs. This paper presents a novel Fault-Tolerant NoC design for butterfly-fat-tree (BFT) topology with flexible spare core placement by taking different benchmark applications into consideration. The major challenge in fault-tolerant NoC is placement of spare core in the event of core failure in BFT network. Therefore, we have proposed an integer linear programming (ILP)-based exact method and particle swarm optimisation (PSO)-based meta-heuristic technique to place the spare core in a BFT network. Our major contribution is to place the spare core in BFT network such that system performance is improved in terms of communication cost, network latency, and router power consumption. Experimentations have been performed on several application benchmarks reported in the literature, (i) by varying the network size with fixed fault-percentage in the network, (ii) by varying the percentage of faults while fixing the network size and (iii) by taking multiple failed cores as a user input. We have compared overall communication cost obtained using our approaches with native fault-free approach. We have also compared overall communication cost and CPU runtime between ILP and PSO. The results show improvement in terms of overall communication cost, average network latency and network power consumption using our approaches compared to fault-free approach in BFT networks.

Fault-Tolerant Network-on-Chip Design with Flexible Spare Core Placement

Network-on-Chip (NoC) has been proposed as a promising solution to overcome the communication challenges of System-on-Chip (SoC) design in nanoscale technologies. With the advancement in the nanoscale technology, the integration density of Intellectual Property (IP) cores in a single chip have increased, leading to heat dissipation, which in turn makes the system unreliable. Therefore, efficient fault-tolerant methods are necessary at different levels to improve overall system performance and make the system to operate normally. This article presents a flexible spare core placement technique for mesh-based NoC by taking several benchmark applications into consideration. An Integer Linear Programming (ILP)-based solution has been proposed for the spare core placement problem. Also, Particle Swarm Optimisation (PSO)-based meta-heuristic has been proposed for the same. Experiments have been performed by taking several application benchmarks reported in the literature and the applications generated using the TGFF tool. Comparisons have been carried out using our approach and the approach followed in the literature (i) by varying the network size with fixed fault percentage in the network, and (ii) by fixing the network size while varying the percentage of faults in the network. We have also compared the overall communication cost and CPU runtime between ILP and PSO approaches. The results show significant reductions in the overall communication cost, average network latency, and network power consumption across all the cases using our approach over the approaches reported in the literature.

A Comparative Analysis of Fracture Resistance and Mode of Failure of Endodontically Treated Teeth Restored Using Different Fiber Posts: An In Vitro Study

To evaluate the fracture resistance under static loading of endodontically treated teeth (maxillary central incisors) restored with carbon fiber posts, glass fiber posts, and everStick posts. The objectives of this study were to check the fracture resistance of the everStick post and compare it with glass fiber posts and carbon fiber posts and evaluated their modes of failure. An estimated 80 freshly extracted human maxillary central incisors were collected for this study. The coronal portions of 60 teeth were sectioned 4 mm incisal to the cemento-enamel junction (CEJ) and 20 teeth were left intact to be used as controls. All the samples were embedded vertically in acrylic resin blocks and the groups were divided as follows. I-control group, II-carbon fiber group, III-glass fiber group, and IV-everStick (E-glass) group. Root canal treatment was completed in all the 80 teeth of 4 groups. Control group teeth were restored with a composite. In all other teeth, post and core placement was carried out. All specimens were mounted on a test block and subjected to static loading until fracture and the mode of fracture was recorded. Statistical analysis was carried out using ANOVA to calculate the mean values of all groups. An intergroup comparison was carried out using Tukey's post hoc test. The study showed that group I showed the highest fracture resistance followed by group IV, which is everStick post group under static loading. There was a significant difference among test groups. The main mode of fracture was repairable as there was debonding of the core in all the fiber posts. Teeth of the control group showed highest fracture resistance and teeth restored with everStick posts showed higher fracture resistance than those restored with glass fiber or carbon fiber posts under static loading (p < 0.05). The principal mode of fracture was debonding of core and remaining root. Teeth restored without application of a post showed the highest fracture resistance than all other groups. EverStick/E-glass fiber posts showed significantly higher fracture resistance than the other fiber posts and can be suggested for clinical use. How to cite this article: Doshi P, Kanaparthy A, Kanaparthy R, et al. A Comparative Analysis of Fracture Resistance and Mode of Failure of Endodontically Treated Teeth Restored Using Different Fiber Posts: An In Vitro Study. J Contemp Dent Pract 2019;20(10):1195-1199.

Case studies of high-rise buildings: A comparative study: Design strategies for energy-efficiency of high-rise office buildings

Tall buildings are being designed and built across a wide range of cities. A poorly designed tall building can tremendously increase the building’s appetite for energy. Therefore, this paper aims to determine the design strategies that help a high-rise office building to be more energy efficient. For this purpose, a comparative study on twelve case buildings in three climate groups (temperate, sub-tropical & tropical) was performed. The exterior envelope, building form and orientation, service core placement, plan layout, and special design elements like atria and sky gardens were the subject of investigation. The effectiveness of different design strategies for reducing the cooling, heating, ventilation and electric lighting energy were analysed. Finally, lessons from these buildings were defined for the three climates. Furthermore, a comparison of building energy performance data with international benchmarks confirmed that in temperate and sub-tropical climates sustainable design strategies for high-rise buildings were performing well, as a result leading to lower energy consumption. However, for the tropics the design of high-rise buildings needs higher concern.

Estimation of RQD by digital image analysis using a shadow-based method

We propose a method for segmentation of cores and estimation of RQD from digital images of rows of core in core boxes in order to compute RQD in an automatic way by finding and locating natural fractures in cores and measuring intact core lengths. First, three digital true color images of a core box, with the same camera position but different light source positions, are taken using a high resolution camera. After detection of the core box with color thresholding, the sections of the box are detected by using Hough transform and boundary tracing algorithms. Then, the cores are extracted from each section using color thresholding. After cleaning shadows created by different light sources using various techniques, non-cylindrical parts of the cores are detected. Finally, RQD is calculated by measuring the valid centerline lengths of each core. All coding routines are written in MATLAB. Twenty different core boxes with 4 and 5 rows storing HQ and NQ diameter cores having various joint/bedding plane angles are photographed several times with different core placements. It is shown that the method is capable of separating even tightly fit joint surface cores. Moreover, it can successfully detect non-cylindrical parts of the cores, and avoid small or irregularly shaped ones which should not be included in RQD calculation. According to the comparison of the manual measurements of the twenty core boxes used to conduct this study, the algorithm is able to compute RQD within an average error rate of 4.8% in 90 to 200 s, depending on the processing power.

Core network function placement in self-deployable mobile networks

Emerging mobile network architectures (e.g., aerial networks, disaster relief networks) are disrupting the classical careful planning and deployment of mobile networks by requiring specific self-deployment strategies. Such networks, referred to as self-deployable, are formed by interconnected rapidly deployable base stations that have no dedicated backhaul connection towards a traditional core network. Instead, an entity providing essential core network functionalities is co-located with one of the base stations. In this work, we tackle the problem of placing this core network entity within a self-deployable mobile network, i.e., we determine with which of the base stations it must be co-located. We propose a novel centrality metric, the flow centrality, which measures a node capacity of receiving the total amount of flows in the network. We show that in order to maximize the amount of exchanged traffic between the base stations and the core network entity, under certain capacity and load distribution constraints, the latter should be co-located with the base station having the maximum flow centrality. We first compare our proposed metric to other state of the art centralities. Then, we highlight the significant traffic loss occurring when the core network entity is not placed on the node with the maximum flow centrality, which could reach 55% in some cases.

Core group placement: allocation and provisioning of heterogeneous resources

We present a theoretical and empirical study on a recently introduced combinatorial optimization problem, namely core group placement problem. The problem arises from real-world business requirements as part of resource allocation in cloud management. In particular, it focuses on the allocation and provisioning of a set of heterogeneous resources serving multiple customers each with different service-level agreements. There exist certain business rules that govern the application stemming from privacy, performance, and capacity requirements. From a theoretical point of view, we prove that the problem is intrinsically hard, yet, from a practical point of view, we show how to formulate it as a constrained optimization program using constraint programming (CP), and alternatively, using mathematical programming (MP). Our experimental results demonstrate that the CP solution outperforms its MP counterpart. We then move toward a dynamic setting where the problem manifests itself in the real world. We show that CP model not only addresses the resource allocation problem but it also enables resource provisioning to take future considerations and system growth into account when making decisions. Overall, the CP solution stands out as a high-level, declarative solution that is efficient, easy to maintain and can address multiple scenarios.

Prosthetic Rehabilitation using a Telescopic Crown constructed with Computer-assisted Design and Computer-assisted Manufacturing: A Case Report with a 2-year Follow-up

Aim and background: This case report describes a 74-year-old female patient whose teeth were rehabilitated using telescopic crowns (TCs) on abutments and fixed dental prostheses (FDPs) in the maxillary arch with the aid of computer-assisted design and computer-assisted manufacturing (CAD/CAM) technology. The mandibular arch was restored using casted removable dental prostheses (RDPs) and surveyed crowns. Case report: The treatment sequences were followed as recommended in the dental literature. First, existing defective restorations were eliminated, caries was removed, and excellent mouth preparation was performed. Subsequently, root canal treatments and post and core placements were conducted. The casts were mounted, and a new vertical dimension was established. Maxillary telescopic FDP and mandibular prostheses were fabricated. Finally, a regular and proper follow-up and maintenance program was implemented. Conclusion: The patient was satisfied with the esthetics and function of the telescopic FDP in the presence of the established occlusion. Clinical significance: The secondary coping of the telescopic FDP is cemented with temporary cement, which can be changed easily whenever it is loose. Furthermore, it is completely opposed to RDP in the mandibular posterior masticatory area. The prognoses will be good improvement; the patient was medically fit, motivated, and followed continual oral hygiene protocol. Keywords: Computer-assisted design, Computer-assisted manufacturing, Esthetic, Maxilla, Telescopic crown.

Area Constrained Performance Optimized ASNoC Synthesis with Thermal‐aware White Space Allocation and Redistribution

Application-Specific Network-on-Chip (ASNoC) has emerged as a more efficient design alternative to the regular Network-on-Chip (NoC) topologies, which can better suit the communication requirements of an application. In this work, we have proposed a three step ASNoC synthesis procedure that targets optimization of the three major design parameters – area of the chip, communication cost (CC) of the resulting on-chip network and the peak temperature of the chip (Tpeak). Inputs to the procedure are the core dimensions, corresponding average power consumptions and the core graph of the application. In the first step, an area-optimized floorplanning of the cores has been conducted. Considering an overhead constraint on the minimum area generated in this step, a communication cost aware floorplan has been generated in the second step. Finally, considering an overhead constraint on the minimum CC obtained from the second step, a thermal-aware white space allocation and redistribution (WSA&R) has been carried out. At each step, Mixed Integer Linear Programming (MILP) formulation has been made along with heuristic or meta-heuristic methods. Core placement has been performed using a Simulated Annealing (SA) based technique with its initial solution generated using a Particle Swarm Optimization (PSO) based approach. A router placement heuristic has been proposed that considers core rotation and core mirroring techniques to optimally place the primary routers. WSA&R has been performed using an iterative SA-based approach. At each stage of the design flow, we have compared our proposed method with an MILP based method and other contemporary heuristics. Significant improvements have been achieved in both CC and Tpeak. The proposed WSR method has been able to reduce Tpeak up to 22°, considering 35% overhead on CC.

Static stages for heterogeneous programming

Heterogeneous hardware is central to modern advances in performance and efficiency. Mainstream programming models for heterogeneous architectures, however, sacrifice safety and expressiveness in favor of low-level control over performance details. The interfaces between hardware units consist of verbose, unsafe APIs; hardware-specific languages make it difficult to move code between units; and brittle preprocessor macros complicate the task of specializing general code for efficient accelerated execution. We propose a unified low-level programming model for heterogeneous systems that offers control over performance, safe communication constructs, cross-device code portability, and hygienic metaprogramming for specialization. The language extends constructs from multi-stage programming to separate code for different hardware units, to communicate between them, and to express compile-time code optimization. We introduce static staging, a different take on multi-stage programming that lets the compiler generate all code and communication constructs ahead of time. To demonstrate our approach, we use static staging to implement BraidGL, a real-time graphics programming language for CPU-GPU systems. Current real-time graphics software in OpenGL uses stringly-typed APIs for communication and unsafe preprocessing to generate specialized GPU code variants. In BraidGL, programmers instead write hybrid CPU-GPU software in a unified language. The compiler statically generates target-specific code and guarantees safe communication between the CPU and the graphics pipeline stages. Example scenes demonstrate the language's productivity advantages: BraidGL eliminates the safety and expressiveness pitfalls of OpenGL and makes common specialization techniques easy to apply. The case study demonstrates how static staging can express core placement and specialization in general heterogeneous programming.

High-performance and energy-efficient fault-tolerance core mapping in NoC

Network on Chip (NoC) has been proposed as an efficient solution to communication problems in on-chip processors. The probability of failure increases in these systems because the complexity involved in continuous device scaling and the number of components embedded on a chip increases. Therefore, a fault-tolerant design has become a key aspect of designing chips to enhance the system reliability. This paper proposes a system-level mapping technique called FTCM, which enhances the performance and communication energy. It emphasizes on core mapping based on the application core graph and spare core placement in non faulty available processing cores because of core failures in the NoC. This technique mainly focuses on the issue of spare core allocation and its impact on the system performance. Experimental results shows that the communication energy conservation in FTCM is 16.8% compared with FASA and 19.2% compared with FARM, performance improvement of FTCM is 12.6% compared with FASA and 14.77% compared with FARM. Moreover, our method is applicable to both random and distributed core graphs.

Gliding Resistance After Epitendinous-First Repair of Flexor Digitorum Profundus in Zone II

The importance of flexor tendon repair with both core and epitendinous suture placement has been well established. The objective of this study was to determine whether suture placement order affects gliding resistance and bunching in flexor digitorum profundus tendons in a human exvivo model. The flexor digitorum profundus tendons of the index, middle, ring, and little fingers of paired cadaver forearms were tested intact for excursion and mean gliding resistance in flexion and extension across the A2 pulley. Tendons were subsequently transected and repaired with either an epitendinous-first (n= 12) or a control (n= 12) repair. Gliding resistance of pair-matched tendons were analyzed at cycle 1 and during the steady state of tendon motion. The tendon repair breaking strength was also measured. The mean steady state gliding resistance was less for the epitendinous-first repair than for the control repair in flexion (0.61 N vs 0.72 N) and significantly less in extension (0.68 N vs 0.85 N). Similar results were seen for cycle 1. None of the repairs demonstrated gap formation; however, control repairs exhibited increased bunching. Load to failure was similar for both groups. The order of suture placement for flexor tendon repair is important. Epitendinous-first repair significantly decreased mean gliding resistance, allowed for easier placement of core sutures, and resulted in decreased bunching. Epitendinous-first flexor tendon repairs may contribute to improved clinical outcomes compared with control repairs by decreasing gliding resistance and bunching.

MP52-14 TRUS ROBOT-ASSISTED PROSTATE BIOPSY: A FEASIBILITY STUDY

You have accessJournal of UrologySurgical Technology & Simulation: Instrumentation & Technology I1 Apr 2017MP52-14 TRUS ROBOT-ASSISTED PROSTATE BIOPSY: A FEASIBILITY STUDY Misop Han, Sunghwan Lim, Changhan Jun, Doru Petrisor, and Dan Stoianovici Misop HanMisop Han More articles by this author , Sunghwan LimSunghwan Lim More articles by this author , Changhan JunChanghan Jun More articles by this author , Doru PetrisorDoru Petrisor More articles by this author , and Dan StoianoviciDan Stoianovici More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1644AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES A freehand TRUS-guided prostate biopsy has significant limitations with spatially clustered and poorly targeted biopsy cores (J Urol. 2012 Dec;188(6):2404-9.) We have developed a novel, 4 degree of freedom (DoF) robotic TRUS probe manipulator (TRUS Robot) (Urology 2011; 77:502-7). Here, we examined the feasibility of image-guided navigation during prostate biopsy using TRUS Robot by obtaining TRUS images of the prostate gland and guiding the biopsy using a geometrically distributed biopsy cores. METHODS TRUS Robot was updated to allow handling of an end-fire TRUS probe and an easy passage of the prostate biopsy needle. Three-dimensional (3-D) image reconstruction, navigation, and core placement software were also developed to allow the geometric core distribution and to align the probe on target for biopsy with minimal motion of the probe around the prostate and between the biopsy cores. RESULTS After IRB approval and informed consent were obtained, 3 subjects underwent TRUS Robot-guided prostate biopsy without complications. The TRUS Robot allowed a steady handling and remote manipulation of the TRUS probe during biopsy. After a manual positioning of the TRUS probe, an automated spin motion of TRUS Robot allowed the acquisition of the entire gland and its 3-D reconstruction. Selection of the extended sextant biopsy core locations was done in the images. Then, the robot oriented the TRUS probe on each target and biopsy cores were obtained manually through the needle guide under direct ultrasound visualization. TRUS Robot and software allowed a smooth and minimal movement between biopsy cores. The accuracy and precision of core targeting according to the plan were 0.49 and 0.22mm, respectively. CONCLUSIONS TRUS Robot-guided prostate biopsy is safe and feasible. It helps define a biopsy plan, provides a mechanism to accurately sample the gland accordingly, and gives a quantitative quality control on the actual distribution of the cores. A successful TRUS Robot-guided prostate procedure provides crucial spatial information of the biopsy cores for improved cancer detection, treatment, and monitoring. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e709 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Misop Han More articles by this author Sunghwan Lim More articles by this author Changhan Jun More articles by this author Doru Petrisor More articles by this author Dan Stoianovici More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Integrated Through-Silicon Via Placement and Application Mapping for 3D Mesh-Based NoC Design

This article proposes a solution to the integrated problem of Through-Silicon Via (TSV) placement and mapping of cores to the routers in a three-dimensional mesh-based Network-on-Chip (NoC) system. TSV geometry restricts their number in three-dimensional (3D) ICs. As a result, only about 25% of routers in a 3D NoC can possess vertical connections. Mapping plays an important role in evolving good system solutions in such a situation. TSVs have been placed with detailed consultation with the application mapping process. The integrated problem was first solved using the exact method of Integer Liner Programming (ILP). Next, a solution was obtained via a Particle Swarm Optimization (PSO) formulation. Several augmentations to the basic PSO strategy have been proposed to generate good-quality solutions. The results obtained are better than many of the contemporary approaches and close to the theoretical situation in which all routers are 3D in nature.

A COMPARATIVE STUDY: DESIGN STRATEGIES FOR ENERGY-EFFICIENCY OF HIGH-RISE OFFICE BUILDINGS

Tall buildings are being designed and built across a wide range of cities. A poorly designed tall building can tremendously increase the building's appetite for energy. Therefore, this paper aims to determine the design strategies that help a high-rise office building to be more energy efficient. For this purpose, a comparative study on twelve case buildings in three climate groups (temperate, sub-tropical &amp; tropical) was performed. The exterior envelope, building form and orientation, service core placement, plan layout, and special design elements like atria and sky gardens were the subject of investigation. effectiveness of different design strategies for reducing the cooling, heating, ventilation and electric lighting energy usage. Finally, lessons from these buildings' were defined for the three climates. Furthermore, a comparison of building energy performance data with international benchmarks confirmed that in temperate and sub-tropical climates sustainable design strategies for high-rise buildings were performing well, as a result leading to lower energy consumption. However, for the tropics the design of high-rise buildings needs additional consideration.

Biologic width: Concept and violation

The tooth and its supporting structures should be viewed as one biologic unit. An understanding of the periodontal-restorative relationship is necessary for the proper form, function, and esthetics of restoration and comfort to the patient. The dimension of the space that the healthy gingival tissue occupies above the alveolar crest is known as the biologic width. The concept of biologic width gains importance in the case of extensive caries management, subgingival margin placement, crown/root fractures, orthodontic banding, subgingival perforation and post, and core placement in endodontic therapy. Biologic width is important for the preservation of periodontal health which eventually decides the success of restorative procedures. This article discusses the anatomy, categories, evaluation, violation, and methods to correct the violation of biologic width.

Using Genetic Algorithms for Hardware Core Placement and Mapping in NoC-Based Reconfigurable Systems

Mapping of cores has been an important activity in NoC-based system design aimed to find the best topological location onto the NoC, such that the metrics of interest can be greatly optimized. In the last years, partial reconfigurable systems (PRSs) have included Networks-on-Chips (NoCs) as their communication structure, adding complexity to the problem of mapping. Several works have proposed specific and robust NoC architectures for PRSs, forming indirect and irregular networks, in which cases the mapping and placement problems must be treated altogether. The placement deals with the physical positioning of those cores inside the reconfigurable device. Up to now, to the best of our knowledge, the mapping-placement problem for those kinds of architectures has not been addressed yet. In this work, the problem formalization for the design-time hardware core placement and mapping in PRS-NoCs is proposed and methodologies for solving it with genetic algorithms (GAs) are presented. Several GA crossovers and methodologies are compared for obtaining the best solution. Results have shown that best GA solution obtained, in average, communication costs with 4% of penalty when compared with global minimum cost, obtained in a semiexhaustive approach. In addition, the algorithm presents low execution times.

Connecting Silicon Photonic Circuits to Multicore Fibers by Photonic Wire Bonding

Photonic wire bonding is demonstrated to enable highly efficient coupling between multicore fibers and planar silicon photonic circuits. The technique relies on in-situ fabrication of three-dimensional interconnect waveguides between the fiber facet and tapered silicon-on-insulator waveguides. Photonic wire bonding can easily compensate inaccuracies of core placement in the fiber cross-section, does not require active alignment, and is well suited for automated fabrication. We report on the design, on fabrication, and on characterization of photonic wire bonds. In a proof-of-principle experiment, a four-core fiber is coupled to a silicon photonic chip, leading to measured coupling losses as small as 1.7 dB.

Practical feasibility evaluation and improvement of a pay-per-use licensing scheme for hardware IP cores in Xilinx FPGAs

In earlier published work, Maes et al. present a pay-per-use licensing scheme for hardware Intellectual Property (IP) cores. This scheme focuses on the use of IP cores on static random access memory-based field programmable gate arrays (FPGAs) and is mainly based on the partial reconfigurability property of this type of FPGA. Our work evaluates the practical feasibility of the scheme and the accompanying architecture. As already (partly) indicated by Maes et al., their solution introduces some security and usability issues. Therefore, we present improvements to the scheme and the architecture together with an additional method for decreasing the area overhead. The overall result is the first practical implementation of the pay-per-use licensing scheme occupying 841 slices on a Xilinx XC6S-LX45 FPGA. The small area overhead is mainly achieved by moving the storage of keys from slice flip-flops to configuration memory. Moreover, the implementation would not have been feasible with commercially available tools. We use an academic tool that allows nested partial reconfiguration and flexible IP core placement.

A Novel Framework for the Design of Adaptable Reconfigurable Partitions for the Placement of Variable-sized IP Cores

This letter presents a novel framework for the design of adjustable reconfigurable partitions for the placement of variable-sized IP cores on embedded reconfigurable systems. It enables the rapid and easy to use methodology for the generation of adaptive computation and communication infrastructure for partial dynamic reconfiguration. The methodology allows an adaptable partition and efficient resource utilization for the placement of reconfigurable modules. The different steps of the proposed framework are detailed. Its effectiveness and benefits are demonstrated through the use of a practical example implemented on a tiled reconfigurable architecture.