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71.
International Journal on Document Analysis and Recognition (IJDAR) - This work addresses the problem of Question Answering (QA) on handwritten document collections. Unlike typical QA and Visual...  相似文献   
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A parameter tolerance, signal to noise ratio comparison is made between the MASH third order sigma-delta modulator structure and a new fourth order cascaded structure. The fourth order structure meets the required performance specification with wider parameter tolerances, allowing easier integration using hybrid CMOS technology.<>  相似文献   
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Abstract

Problem, research strategy, and findings: Despite growing interest by practitioners in using exploratory scenarios within urban planning practice, there are few detailed guidelines for how to do this. Through the discussion of five case examples, we illustrate different approaches to linking exploratory scenarios to different planning contexts. We conclude by observing that to directly inform a plan, regardless of the specific approach taken, exploratory scenarios in urban planning must incorporate stakeholder values and not only rely on expert judgment and analysis.

Takeaway for practice: Exploratory scenarios are effective for analyzing uncertainty within a planning process. However, exploratory scenarios can be incorporated into planning practice in different ways, ranging from workshops among experts that aim to cultivate general learning to complex projects that result in highly detailed scenarios and recommendations for plans. Practitioners can draw on the cases we present to inspire planning methods for particular projects, taking into account specific contexts and goals.  相似文献   
76.
Nouy and Clement introduced the stochastic extended finite element method to solve linear elasticity problem defined on random domain. The material properties and boundary conditions were assumed to be deterministic. In this work, we extend this framework to account for multiple independent input uncertainties, namely, material, geometry, and external force uncertainties. The stochastic field is represented using the polynomial chaos expansion. The challenge in numerical integration over multidimensional probabilistic space is addressed using the pseudo-spectral Galerkin method. Thereafter, a sensitivity analysis based on Sobol indices using the derived stochastic extended Finite Element Method solution is presented. The efficiency and accuracy of the proposed novel framework against conventional Monte Carlo methods is elucidated in detail for a few one and two dimensional problems.  相似文献   
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Human disease elicits a complex array of biological processes that results in long‐term protective immunological memory to infectious agents. Chronic kidney disease is known to impair induction of sustained immunological memory to hepatitis B vaccine (HBVax) antigens. We asked the question: Does end‐stage renal disease promote changes in subtypes of regulatory T (Treg) cells that correlate with diminished amnestic response to HBVax antigen compared to healthy controls? The study design and setting was a prospective observational cohort at a veterans affairs medical center. End‐stage renal disease patients on hemodialysis (HD) were compared with individuals with self‐reported normal kidney function. All subjects received HBVax. Peripheral blood was sampled for assessment for Treg cells pre and post vaccination. CD4+ FOXP3 Treg numbers were similar between HD and healthy subjects during a 14‐day time period post vaccination. HD subjcts had lower anti‐HBSag antibody than CON (control) subjects (330 ± 108.7 vs. 663.1 ± 129.7 IU/mL; P = 0.063). Hemodialysis subjects with resting Tregs higher than the median value in our cohort demonstrated a significantly lower change in HBsAB at 30 days post booster vaccination (P = 0.030). No such relationship was found for the activated Treg subset among HD subjects, or either subset among CON subsets. In our limited comparison study of 11 HD and 8 CON subjects, Treg subsets did not differ between the two groups; but differences in the suppressive Treg numbers in the HD group could explain the altered antibody response to HBVax and is worthy of further study.  相似文献   
79.
Important physical insights regarding the design and performance of independent-gate FinFETs, e.g., the MIGFET , are gained from measured data and predictions from our process/physics-based double-gate (DG) MOSFET model (UFDG) in Spice3. Inversion charge-centroid shifting, modulated by gate biases as well as by quantum-confinement and short-channel effects, underlies the sensitivity of the MIGFET (front-gate) threshold voltage to the back-gate bias. MIGFET design and operation-mode options are examined for optimizing circuit applications. Further, novel design of a single-device RF mixer and a double-balanced counterpart using MIGFETs is studied with UFDG/Spice3. Reasonably good MIGFET mixers, with regard to conversion gain and linearity with small-size/low-voltage/low-power requirements, can be achieved with optimal biases on the two gates and good design of the MIGFET structure.  相似文献   
80.
Mathew Celina  Roger Clough  Gary Jones 《Polymer》2005,46(14):5161-5164
Understanding polymer degradation phenomena is of critical importance for material reliability. A novel dual stage chemiluminescence detection system has been developed and applied to probe for material interaction effects during polymer degradation. Evidence is presented for the first time that in an oxidizing environment a degrading polymer A (in this case polypropylene, PP) is capable of infecting a different polymer B (in this case polybutadiene, HTPB) over a relatively large distance. In the presence of the degrading material A, the thermal degradation of polymer B is observed over a significantly shorter time period. Infectious intermediate volatiles from material A are able to initiate and shorten the degradation processes in material B. This observation documents infectious behavior that will have significant consequences for materials interactions, understanding material degradation processes and long-term aging effects in combined material exposures.  相似文献   
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