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31.
A composite liquid crystalline elastomer is designed, combining main-chain and side-chain mesogenic polymers in the network, and resulting in micro-phase separated regions of nematic and smectic ordering in the macroscopically homogeneous elastomer. A range of different fractions of the components is explored, from fully nematic main-chain system, across to fully smectic side-chain elastomer. Thermal phase transitions of both phases coexisting in the material are detected by calorimetry, and the nematic/smectic structure investigated by X-ray scattering. The tensile stress–strain data reveal the key effect of such a multi-phase composite, where the nematic fraction adds ductility while the smectic fraction increases the modulus and mechanical stiffness. Varying the composition, the authors are able to optimize the mechanical properties of this material type. 相似文献
32.
Identifying and integrating patient and caregiver perspectives for clinical practice guidelines on the screening and management of infectious microorganisms in hemodialysis units 下载免费PDF全文
Hilary M. Miller Allison Tong David J. Tunnicliffe Denise Campbell Jule Pinter Robert J. Commons Eugene Athan Jonathan C. Craig Nicole Gilroy Julianne Green Belinda Henderson Martin Howell Rhonda L. Stuart Carolyn van Eps Muh Geot Wong Janak de Zoysa Meg J. Jardine 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(2):213-223
33.
In 1996 the immunization of children against measles, mumps and rubella with combined vaccine Trimovax ("Pasteur Mérieux Connaught", France) was carried out in the Republic of Belarus. The reactogenicity of the vaccine was studied in 372 children. To evaluate immunological effectiveness, the sera of 324 children were used. Postvaccinal reactions of different intensity were registered in 5.6% of the children; of these, 1.3% exhibited severe reactions. Among the vaccinees, protective titers of antibodies to measles were found in 97.6% to mumps, in 93.8% and to rubella, in 96.0% of the children. Antibodies to all three components of the vaccine were present mainly in high and moderate titers. The results thus obtained indicate that, Trimovax was well tolerated and proved to be immunologically active. 相似文献
34.
Consider an m-machine production line for processing identical parts served by a mobile robot. The problem is to find the minimum cycle
time for 2-cyclic schedules, that is, schedules in which exactly two parts enter and two parts leave the production line during
each cycle. This work treats a special case of the 2-cyclic robot scheduling problem when the robot route is given and operation
durations are chosen from prescribed intervals. A strongly polynomial algorithm of time complexity O(m
8log m) is proposed. 相似文献
35.
Alina Chertock Charles R. Doering Eugene Kashdan Alexander Kurganov 《Journal of scientific computing》2010,45(1-3):200-214
The dispersal and mixing of scalar quantities such as concentrations or thermal energy are often modeled by advection-diffusion equations. Such problems arise in a wide variety of engineering, ecological and geophysical applications. In these situations a quantity such as chemical or pollutant concentration or temperature variation diffuses while being transported by the governing flow. In the passive scalar case, this flow prescribed and unaffected by the scalar. Both steady laminar and complex (chaotic, turbulent or random) time-dependent flows are of interest and such systems naturally lead to questions about the effectiveness of the stirring to disperse and mix the scalar. The development of reliable numerical methods for advection-diffusion equations is crucial for understanding their properties, both physical and mathematical. In this paper, we extend a fast explicit operator splitting method, recently proposed in (A. Chertock, A. Kurganov, G. Petrova, Int. J. Numer. Methods Fluids 59:309–332, 2009), for solving deterministic convection-diffusion equations, to the problems with random velocity fields and singular source terms. A superb performance of the method is demonstrated on several two-dimensional examples. 相似文献
36.
Visualization of diversity in large multivariate data sets 总被引:1,自引:0,他引:1
Pham T Hess R Ju C Zhang E Metoyer R 《IEEE transactions on visualization and computer graphics》2010,16(6):1053-1062
Understanding the diversity of a set of multivariate objects is an important problem in many domains, including ecology, college admissions, investing, machine learning, and others. However, to date, very little work has been done to help users achieve this kind of understanding. Visual representation is especially appealing for this task because it offers the potential to allow users to efficiently observe the objects of interest in a direct and holistic way. Thus, in this paper, we attempt to formalize the problem of visualizing the diversity of a large (more than 1000 objects), multivariate (more than 5 attributes) data set as one worth deeper investigation by the information visualization community. In doing so, we contribute a precise definition of diversity, a set of requirements for diversity visualizations based on this definition, and a formal user study design intended to evaluate the capacity of a visual representation for communicating diversity information. Our primary contribution, however, is a visual representation, called the Diversity Map, for visualizing diversity. An evaluation of the Diversity Map using our study design shows that users can judge elements of diversity consistently and as or more accurately than when using the only other representation specifically designed to visualize diversity. 相似文献
37.
We consider Constraint Satisfaction Problems in which constraints can be initially incomplete, where it is unknown whether
certain tuples satisfy the constraint or not. We assume that we can determine the satisfaction of such an unknown tuple, i.e.,
find out whether this tuple is in the constraint or not, but doing so incurs a known cost, which may vary between tuples.
We also assume that we know the probability of an unknown tuple satisfying a constraint. We define algorithms for this problem,
based on backtracking search. Specifically, we consider a simple iterative algorithm based on a cost limit on the unknowns
that may be determined, and a more complex algorithm that delays determining an unknown in order to estimate better whether
doing so is worthwhile. We show experimentally that the more sophisticated algorithms can greatly reduce the average cost. 相似文献
38.
Increasingly, new regulations are governing organizations and their information systems. Individuals responsible for ensuring legal compliance and accountability currently lack sufficient guidance and support to manage their legal obligations within relevant information systems. While software controls provide assurances that business processes adhere to specific requirements, such as those derived from government regulations, there is little support to manage these requirements and their relationships to various policies and regulations. We propose a requirements management framework that enables executives, business managers, software developers and auditors to distribute legal obligations across business units and/or personnel with different roles and technical capabilities. This framework improves accountability by integrating traceability throughout the policy and requirements lifecycle. We illustrate the framework within the context of a concrete healthcare scenario in which obligations incurred from the Health Insurance Portability and Accountability Act (HIPAA) are delegated and refined into software requirements. Additionally, we show how auditing mechanisms can be integrated into the framework and how auditors can certify that specific chains of delegation and refinement decisions comply with government regulations. 相似文献
39.
Immunity-based hybrid evolutionary algorithm for multi-objective optimization in global container repositioning 总被引:1,自引:0,他引:1
Eugene Y.C. Wong Henry S.C. Yeung Henry Y.K. Lau 《Engineering Applications of Artificial Intelligence》2009,22(6):842-854
The development of evolutionary algorithms for optimization has always been a stimulating and growing research area with an increasing demand in using them to solve complex industrial optimization problems. A novel immunity-based hybrid evolutionary algorithm known as Hybrid Artificial Immune Systems (HAIS) for solving both unconstrained and constrained multi-objective optimization problems is developed in this research. The algorithm adopts the clonal selection and immune suppression theories, with a sorting scheme featuring uniform crossover, multi-point mutation, non-dominance and crowding distance sorting to attain the Pareto optimal front in an efficient manner. The proposed algorithm was verified with nine benchmarking functions on its global optimal search ability as well as compared with four optimization algorithms to assess its diversity and spread. Sensitivity analysis was also carried out to investigate the selection of key parameters of the algorithm. It is found that the developed immunity-based hybrid evolutionary algorithm provides a useful means for solving optimization problems and has successfully applied to the problem of global repositioning of containers, which is one of a constrained multi-objective optimization problem. The developed HAIS will assist shipping liners on timely decision making and planning of container repositioning operations in global container transportation business in an optimized and cost effective manner. 相似文献
40.
While hexahedral mesh elements are preferred by a variety of simulation techniques, constructing quality all‐hex meshes of general shapes remains a challenge. An attractive hex‐meshing approach, often referred to as sub‐mapping, uses a low distortion mapping between the input model and a PolyCube (a solid formed from a union of cubes), to transfer a regular hex grid from the PolyCube to the input model. Unfortunately, the construction of suitable PolyCubes and corresponding volumetric maps for arbitrary shapes remains an open problem. Our work introduces a new method for computing low‐distortion volumetric PolyCube deformations of general shapes and for subsequent all‐hex remeshing. For a given input model, our method simultaneously generates an appropriate PolyCube structure and mapping between the input model and the PolyCube. From these we automatically generate good quality all‐hex meshes of complex natural and man‐made shapes. 相似文献