The fabrication of a functional part requires very high layer quality in the Fused Deposition (FD) processes. The constant deposition flow rate currently used in FD technology cannot meet this requirement, due to the ...
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The fabrication of a functional part requires very high layer quality in the Fused Deposition (FD) processes. The constant deposition flow rate currently used in FD technology cannot meet this requirement, due to the varying geometries of the layers. To achieve a high quality functional part, an overfill and underfill analysis is conducted. A deposition planning approach is proposed, which is based on a grouping and mapping algorithm. Two piezoelectric test parts have been built to demonstrate the effectiveness and feasibility of the proposed approach.
As a success-oriented system reliability and safety-analysis technique, the GO methodology has been applied in a variety of real-world safety-critical industrial fields. Common-cause failure (CCF) is the simultaneous ...
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As a success-oriented system reliability and safety-analysis technique, the GO methodology has been applied in a variety of real-world safety-critical industrial fields. Common-cause failure (CCF) is the simultaneous failure of multicomponents within a system due to the same root cause. An enhancement approach for the original GO methodology is proposed in this paper to support CCF modeling and calculation both in graphical modeling aspect and algorithm aspect. First, a new concise and formalized GO operator (named CCO) is introduced to represent complicated CCF event, which makes the CCF modeling process intuitive and concise for analysts. In algorithm aspect, the mapping rule is given and demonstrated to transform new CCO operator with impacted multiple operators to the corresponding Bayesian network (BN) fragment. Second, general mapping programmable process is presented on transforming any CCF enhanced GO model to the corresponding BN. Furthermore, using BN's inference capability, the enhanced GO model with CCF can be calculated efficiently. Nevertheless, the diagnosis process can be performed to investigate the weak points of the modeled system. Finally, a case study is performed to demonstrate the modeling process by means of CCF enhanced GO model. The calculation result shows that CCF has significant influence on the system reliability. Using diagnosis analysis, the CCF event can be confirmed as the major cause leading to system failure.
mapping of IP cores on a given platform is one of the three aspects of Network-on-Chip design. mapping priority of IP cores is mostly based on a single communication in previously proposed algorithms. In this paper we...
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mapping of IP cores on a given platform is one of the three aspects of Network-on-Chip design. mapping priority of IP cores is mostly based on a single communication in previously proposed algorithms. In this paper we present Chain-mapping (CHMAP), as an algorithm for mapping cores onto a mesh-based Network-on-Chip architecture. The main aim of the algorithm is to produce chains of connected cores in order to introduce a new method to prioritize IP core which helps us to have more efficient mapping. Proposed algorithm and previous researches were compared on two real applications, i.e. Video object plan decoder (VOPD) and MPEG-4 and results were
The ultimate aim of this work is the development of methods for the simulation of manufacturing process chains such as forming --> cutting --> heat treatment --> joining, providving maximal efficiency without...
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The ultimate aim of this work is the development of methods for the simulation of manufacturing process chains such as forming --> cutting --> heat treatment --> joining, providving maximal efficiency without significant loss of accuracy. In the current work, we make the first step in this direction by considering the case of forming of the new high strength steel LH(R)800. The work begins with a characterization and metallographic investigation of this new steel. Following this, a combined hardening model appropriate for this steel is formulated and identified. The identified model is then validated with the help of the finite-element simulation of draw-bending. On this basis, the model was then used to simulate cup deep-drawing. This process was also simulated with a so-called one-step solver which is much faster than the finite element simulation. The results of these two simulations are compared with the results of the deep-drawing experiment.
Magnetic flux leakage (MFL) testing is the most widely used for the in-service inspection of oil and gas pipelines. The variation of sensors liftoff caused by vibration results in the distortion of the defect signals,...
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Magnetic flux leakage (MFL) testing is the most widely used for the in-service inspection of oil and gas pipelines. The variation of sensors liftoff caused by vibration results in the distortion of the defect signals, thereby decreasing the estimation performance of the defect profile. In this paper, we discuss the effects of the detector vibration on the MFL signal and propose a sensor liftoff modification method of an MFL signal based on the finite-element method simulation. The proposed method mainly introduces a mapping algorithm to modify original measured signal and obtain pure signal. This mapping algorithm is constructed by iterative defect models closed to the real defect. The algorithm effectiveness is tested by using simulation and experiment data. The results demonstrate that the proposed method can improve the signal-to-noise ratio and estimate the profile more accurately.
The purpose of this correspondence is to provide an example computer logic graph and data concerning various partitions and mappings of this graph. This information should be of particular interest to those workers wh...
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The purpose of this correspondence is to provide an example computer logic graph and data concerning various partitions and mappings of this graph. This information should be of particular interest to those workers who are developing partitioning and mapping algorithms, since it provides a means to test and compare alternative methods. It should also be of use to those interested in other algorithms (e.g., placement, diagramming, grouping, etc.) for logic graphs.
Purpose The Quality of Life Alzheimer's Disease Scale (QoL-AD) is commonly used to assess disease specific health-related quality of life (HRQoL) as rated by patients and their carers. For cost-effectiveness analy...
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Purpose The Quality of Life Alzheimer's Disease Scale (QoL-AD) is commonly used to assess disease specific health-related quality of life (HRQoL) as rated by patients and their carers. For cost-effectiveness analyses, utilities based on the EQ-5D are often required. We report a new mapping algorithm to obtain EQ-5D indices when only QoL-AD data are available. Methods Different statistical models to estimate utility directly, or responses to individual EQ-5D questions (response mapping) from QoL-AD, were trialled for patient-rated and proxy-rated questionnaires. Model performance was assessed by root mean square error and mean absolute error. Results The response model using multinomial regression including age and sex, performed best in both the estimation dataset and an independent dataset. Conclusions The recommended mapping algorithm allows researchers for the first time to estimate EQ-5D values from QoL-AD data, enabling cost-utility analyses using datasets where the QoL-AD but no utility measures were collected.
Power consumption has become one of the primary challenges to meet Moore's law. For reducing power consumption, single-electron transistor (SET) at room temperature has been demonstrated as a promising device for ...
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Power consumption has become one of the primary challenges to meet Moore's law. For reducing power consumption, single-electron transistor (SET) at room temperature has been demonstrated as a promising device for extending Moore's law due to its ultralow power consumption in operation. Previous works have proposed automated mapping approaches for SET arrays that focused on minimizing the number of hexagons in the SET arrays. However, the area of an SET array is the product of the bounded height and the bounded width, and the height usually equals the number of inputs in the Boolean function. Consequently, in this paper, we focus on the width minimization to reduce the overall area in the mapping of the SET arrays. Our approach consists of techniques of product term minimization, branch-then-share (BTS)-aware variable reordering, SET array architecture relaxation, and BTS-aware product term reordering. The experimental results on a set of MCNC and IWLS 2005 benchmarks show that the proposed approach saves 45% of width compared with the work by Chiang et al., which focused on hexagon count minimization, and also saves 13% of width compared with the work by Chen et al., which focused on width minimization.
Flexible macroblock ordering (FMO) is a new error resilience feature in the H.264 (MPEG-4 part 10) video coding standard. The paper exploits FMO to offer a new classification algorithm for prioritised video transmissi...
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Flexible macroblock ordering (FMO) is a new error resilience feature in the H.264 (MPEG-4 part 10) video coding standard. The paper exploits FMO to offer a new classification algorithm for prioritised video transmission. Instead of using the default mapping structures of FMO, an optimisation algorithm in which the more important macroblocks (MBs) are categorised in a separate slice group (SG), which corresponds to high-priority packets for transmission, is proposed. The importance of each MB is determined based on its eventual influence on picture quality. This is assessed by considering the fact that the successful transmission of an MB not only enhances the quality of the associated pixels, but also improves the quality of its adjacent lost MBs by improving the efficiency of error concealment. It is assumed that the network can offer a prioritised service for successful transmission of the high-priority SG. Based on this, a vulnerability factor for each MB is determined, and a certain proportion of high-vulnerability MBs at each frame to limit the impact of temporal error propagation is intra-updated. It is shown, where the proposed mapping algorithm outperforms the default mappings of the H.264 codec, that this prioritised transmission will improve the subjective and objective video quality in situations with a high probability of transmission errors.
The macular degeneration quality of life (MacDQoL) instrument is a validated condition-specific measure of quality of life in patients with macular degeneration. This paper presents the first mapping algorithm to pred...
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The macular degeneration quality of life (MacDQoL) instrument is a validated condition-specific measure of quality of life in patients with macular degeneration. This paper presents the first mapping algorithm to predict EQ-5D from responses to the MacDQoL instrument. Responses to the MacDQoL and EQ-5D-3L instruments from 482 patients were collected from the IVAN multicentre trial of two alternative drug treatments for neovascular age-related macular degeneration. Regression specifications were estimated using OLS, censored least absolute deviation, Tobit and two-part models. Their predictive performance was assessed using mean squared error. An internal validation sample based on a random selection of 25 % of patients was used to assess the performance of the model estimated on the remaining 75 % of patients. A two-part model had the best predictive performance on the full sample. The covariates of this model include responses and weighted impact scores for all 23 condition-specific domains of the MacDQoL, and responses to a general MacDQoL quality of life question. The selected models were successful at predicting means and standard deviations of target populations, but prediction is weaker at the upper and lower extremes of the EQ-5D-3L distribution. The mapping algorithms provide a means of predicting EQ-5D-3L index scores from MacDQoL scores, and could facilitate cost-effectiveness analyses when the latter but not the former are available to researchers. Further validation of the performance of the algorithms using external data would provide a means of establishing the robustness of the algorithms.
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