检索结果-内蒙古大学图书馆

Characterization and quantification of gait deficits within gait phases using fuzzy-granular computing

Journal of Biomedical science and engineering 2012年第12期5卷 720-728页

作者： Melaku A. Bogale Huiying Yu Thompson Sarkodie-Gyan Amr Abdelgawad Texas Tech University Health Science Center El Paso USA University of Texas at El Paso Computational Science Program El Paso USA University of Texas at El Paso Department of Electrical and Computer Engineering El Paso USA

People with neurological disorders like Cerebral Palsy (CP) and Multiple Sclerosis (MS) suffer associated functional gait problems. The symptoms and sign of these gait deficits are different between subjects and even within a subject at different stage of the disease. Identifying these gait related abnormalities helps in the treatment planning and rehabilitation process. The current gait assessment process does not provide very specific information within the seven gait phases. The objective of this study is to investigate the possible application of granular computing to quantify gait parameters within the seven gait phases. In this process we applied fuzzy-granular computing on the vertical ground reaction force (VGRF) and surface electromyography (sEMG) data to obtain respective characteristic values for each gait phase. A fuzzy similarity (FS) measure is used to compare patient values with age and sex matched control able-bodied group. We specifically applied and tested this approach on 10 patients (4 Cerebral Palsy and 6 Multiple Sclerosis) to identify possible gait abnormalities. Different FS values for VGRF for right and left leg is observed. The VGRF analysis shows smaller FS values during the swing phase in CP and MS subjects that are evidence of associated stability problem. Similarly, FS values for muscle activates of the four-selected muscle display a broad range of values due to difference between subjects. Degraded FS values for different muscles at different stage of the gait cycle are reported. Smaller FS values are sign of abnormal activity of the respective muscles. This approach provides individual centered and very specific information within the gait phases that can be employed for diagnosis, treatment and rehabilitation process.

关键词： Fuzzy-Granular Algorithm Gait Phases Fuzzy Similarity Cerebral Palsy Multiple Sclerosis

来源：评论

学校读者我要写书评

暂无评论

Response of aqueous dichromate and nanoclay dichromate gel dosimeters to carbon ion irradiation

引用

Journal of Physics: Conference Series 2013年第1期444卷

作者： T Maeyama N Fukunishi K L Ishikawa K Fukasaku T Furuta S Takagi S Noda R Himeno S Fukuda RIKEN/Nishina Center for Accelerator-Based Science Wako Japan RIKEN/Computational Science Research Program Wako Japan The University of Tokyo/Department of Nuclear Engineering and Management Graduate School of Engineering Tokyo Japan The University of Tokyo/Photon Science Center Graduate School of Engineering Tokyo Japan Himon'ya Hospital/ Department of Neurosurgery Tokyo Japan RIKEN/Advanced Center for Computing and Communication Wako Japan The University of Tokyo/Department of Mechanical Engineering Graduate School of Engineering Tokyo Japan National Institute of Radiological Sciences/ Research Center for Charged Particle Therapy Chiba Japan

We have recently reported the significant reduction of radiation product diffusion by the incorporation of clay nanoparticles into dichromate gel (DCG) dosimeters. In this work, we investigate the influence of the nanoclay addition and gelation on the MRI R1 (1/T1) image response of the dichromate dosimeter to the therapeutic carbon ion beam (12C6+ 290 MeV/u). The MRI R1 distribution in the aqueous dichromate solution well reproduces physical dose-depth distribution with a high linear-energy-transfer (LET) efficiency. The nanoclay DCG dosimeters, on the other hand, exhibit composition-dependent LET efficiency degradation, while a sharp Bragg peak can still be detected. These results indicate that the nanocomposite gel addition may induce change in the radiation-induced reaction mechanism.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Numerical study on platelet adhesion to vessel walls using the kinetic Monte Carlo method

引用

Journal of Biomechanical science and engineering 2012年第2期7卷 275-283页

作者： Shiozaki, Seiji Ishikawa, Kenichi L. Takagi, Shu Computational Science Research Program RIKEN 2-1 Hirosawa Wako-shi Saitama 351-0198 Japan School of Engineering The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-8656 Japan

The interaction between platelets and vessel walls in the primary aggregation of platelets was investigated using kinetic Monte Carlo simulation for the multiscale simulation of thrombus formation. The kinetic Monte Carlo lattice model of a platelet surface with glycoprotein Ibα (GPIbα) localization region was simulated by considering 3 types of events: GPIbα diffusion, GPIbα-von Willebrand factor (vWF) bond formation, and breakage. The formation and breakage model of GPIbα-vWF bonds were constructed to reproduce experimental results. Next, the adhesion force between a platelet and vessel wall was evaluated, and the contribution of GPIbα localization in platelet adhesion was investigated. The adhesion force curves with respect to the distance between the platelet and vessel wall were convex upward. The results showed that when the bond formation probability between GPIbα and vWF was small, the localization of GPIbα had a large effect on the adhesion force between the platelet and the vessel wall. © 2012 by JSME.

关键词： Glycoproteins

来源：评论

学校读者我要写书评

暂无评论

Radiological characteristics of charged particle interactions in the first clay-nanoparticle dichromate gel dosimeter

引用

Journal of Physics: Conference Series 2013年第1期444卷

作者： M L Taylor T Maeyama N Fukunishi K L Ishikawa K Fukasaku T Furuta S Takagi S Noda R Himeno S Fukuda RMIT University/School of Applied Sciences Melbourne Australia Peter MacCallum Cancer Centre/Physical Sciences Melbourne Australia RIKEN/Nishina Centre for Accelerator-Based Science Wako Japan RIKEN/Computational Science Research Program Wako Japan The University of Tokyo/Department of Nuclear Engineering and Management Graduate School of Engineering Tokyo Japan The University of Tokyo/Photon Science Centre Graduate School of Engineering Tokyo Japan Himon'ya Hospital Department of Neurosurgery Tokyo Japan RIKEN/Advanced Centre for Computing and Communication Wako Japan The University of Tokyo/Department of Mechanical Engineering Graduate School of Engineering Tokyo Japan National Institute of Radiological Sciences / Research Centre for Charged Particle Therapy Chiba Japan

The incorporation of clay nanoparticles into gel dosimeters shows promise for significant diffusion reduction – but to what extent does the presence of the nano-clay influence charged particle interactions and, in particular, what is the impact on water equivalence? In this work, we quantify the radiological characteristics of electron, proton and carbon ion interactions in the RIKEN dichromate nanoclay gel and specifically evaluate the water equivalence over a broad energy range. Results indicate that the radiological properties are sufficiently representative of tissues that this low-diffusion gel could readily be used for validation of complex dose distributions. Electron and proton ranges are within 1 % of those in water. Mean effective atomic numbers for electron interactions in the range 10 keV – 10 GeV are within 1 % of those of water which, coupled with the similar mass density, ultimately means the overall impact on dose distributions is not great. The range of C6+ ions in the nanoclay gel is closer to that of water (< 4 %) than a common polymer gel dosimeter (< 7 %), though experimentally measured R1 values indicate an over-response at low doses.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Density of States for a Specified Correlation Function and the Energy Landscape

引用

Physical Review Letters 2012年第8期108卷 080601-080601页

作者： C. J. Gommes Y. Jiao S. Torquato Department of Chemical Engineering University of Liège B-4000 Liège Belgium Department of Chemistry Princeton University Princeton New Jersey 08544 USA Program in Applied and Computational Mathematics and Princeton Center for Theoretical Science Princeton University Princeton New Jersey 08544 USA

The degeneracy of two-phase disordered microstructures consistent with a specified correlation function is analyzed by mapping it to a ground-state degeneracy. We determine for the first time the associated density of states via a Monte Carlo algorithm. Our results are explained in terms of the roughness of an energy landscape, defined on a hypercubic configuration space. The use of a Hamming distance in this space enables us to define a roughness metric, which is calculated from the correlation function alone and related quantitatively to the structural degeneracy. This relation is validated for a wide variety of disordered structures.

关键词： ENERGY levels (Quantum mechanics) CORRELATION (Statistics) MICROSTRUCTURE GROUND state (Quantum mechanics) MONTE Carlo method CONFIGURATION space QUANTITATIVE research

来源：评论

学校读者我要写书评

暂无评论

Gorgon and pathwalking: Macromolecular modeling tools for subnanometer resolution density maps

Gorgon and pathwalking: Macromolecular modeling tools for su...

引用

作者： Baker, Matthew L. Baker, Mariah R. Hryc, Corey F. Ju, Tao Chiu, Wah Verna and Marrs McLean Department of Biochemistry and Molecular Biology National Center for Macromolecular Imaging Baylor College of Medicine Houston TX 77030 United States Program in Structural and Computational Biology and Molecular Biophysics Baylor College of Medicine Houston TX 77030 United States Department of Computer Science and Engineering Washington University in St. Louis St. Louis MO 63130 United States

The complex interplay of proteins and other molecules, often in the form of large transitory assemblies, are critical to cellular function. Today, X-ray crystallography and electron cryo-microscopy (cryo-EM) are routinely used to image these macromolecular complexes, though often at limited resolutions. Despite the rapidly growing number of macromolecular structures, few tools exist for modeling and annotating structures in the range of 3-10 Å resolution. To address this need, we have developed a number of utilities specifically targeting subnanometer resolution density maps. As part of the 2010 Cryo-EM Modeling Challenge, we demonstrated two of our latest de novo modeling tools, Pathwalking and Gorgon, as well as a tool for secondary structure identification (SSEHunter) and a new rigid-body/flexible fitting tool in Gorgon. In total, we submitted 30 structural models from ten different subnanometer resolution data sets in four of the six challenge categories. Each of our utlities produced accurate structural models and annotations across the various density maps. In the end, the utilities that we present here offer users a robust toolkit for analyzing and modeling protein structure in macromolecular assemblies at non-atomic resolutions. © 2012 Wiley Periodicals, Inc.

关键词： X ray crystallography

来源：评论

学校读者我要写书评

暂无评论

Multilayer thin film growth on crystalline and quasicrystalline surfaces: A phase-field crystal study

引用

Physical Review B 2012年第24期85卷 245428-245428页

作者： Srevatsan Muralidharan Raika Khodadad Ethan Sullivan Mikko Haataja Department of Mechanical and Aerospace Engineering Princeton Institute for the Science and Technology of Materials (PRISM) Program in Applied and Computational Mathematics (PACM) Princeton University Princeton New Jersey 08544 USA and School of Mathematics Institute for Advanced Study Princeton New Jersey 08540 USA

In this paper, we explore the effects of misfit strain fields on both heterogeneous nucleation behavior and anisotropic growth of islands at submonolayer coverages and compositional patterning at complete monolayer coverage via simulations of a phase-field crystal model. In particular, deposition on top of a herringbone structure and quasicrystalline (QC) substrate are considered, the former representing a system with spatially periodic misfit strain fields arising from the presence of surface dislocations, and the latter representing a system which inherently possesses a wide range of local, aperiodic misfit patterns. In the case of single-component systems, we demonstrate that misfit strain fields lead to heterogeneous nucleation behavior and anisotropic island growth. In the case of QC substrate, a wide range of morphologies, such as coexistence of locally hexagonally ordered atomic clusters within a larger scale arrangement with overall QC symmetry and so-called “starfish” aggregates, is observed in a pure system at submonolayer coverages when the adlayer-substrate interaction strength and lattice mismatch are tuned. In the case of bulk-immiscible binary systems at complete monolayer coverage, strain-stabilized compositional domains emerge at low line tension values for both substrates. Interestingly, the compositional domains on the QC substrate inherit their symmetries at sufficiently low line tension values, while at larger line tension values, the domain structure begins to resemble the classical spinodal microstructure. Such domain structures should be readily observable in colloidal systems in which attractive interparticle and particle-substrate interactions can be tuned.

关键词： THIN films CRYSTALS NUCLEATION DISLOCATIONS in crystals MICROSTRUCTURE

来源：评论

学校读者我要写书评

暂无评论

The effects of brachial arterial stiffening on the accuracy of oscillometric blood pressure measurement: A computational model study

引用

Journal of Biomechanical science and engineering 2012年第1期7卷 15-30页

作者： Liang, Fuyou Liu, Hao Takagi, Shu Computational Science Research Program RIKEN 2-1 Hirosawa Wako Saitama Japan Graduate School of Engineering Chiba University 1-33 Yayoi-cho Inage-ku Chiba-shi Chiba Japan Department of Mechanical Engineering University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo Japan

Oscillometric noninvasive blood pressure measurement (ONBPM) is nowadays widely applied in health care. However, ONBPM has been found to exhibit large interindividual variability in accuracy. In the present study, we developed a theoretical model to describe the mechanics of the brachial arterial wall and particularly arterial stiffening dominated respectively by wall thickening and elastin degeneration. The model was incorporated into a cardiovascular-cuff model to investigate the effects of brachial arterial stiffening on the accuracy of ONBPM. It was found that wall-thickening-dominated arterial stiffening induced overestimate of the systolic pressure, whereas the elastin-degeneration-dominated arterial stiffening induced overestimate of both the systolic pressure and the diastolic pressure. The findings support the clinical observation that pseudo-hypertension is more prevalent in the elderly, and at the same time imply that arterial stiffness indices (e.g., compliance of artery, pulse wave velocity) assessed under the physiological pressure (generally between 70 and 150mmHg) conditions may be insufficient for assessing the accuracy of ONBPM. © 2012 by JSME.

关键词： Elastin

来源：评论

学校读者我要写书评

暂无评论

A Post-Pareto Approach for Multi-Objective Decision Making Using a Non-Uniform Weight Generator Method

引用

Procedia Computer science 2012年 12卷 116-121页

作者： Victor M. Carrillo Heidi Taboada Computational Science Program. The University of Texas at El Paso 500 West University El Paso TX 79968-0521 United States of America Department of Industrial Manufacturing and Systems Engineering. The University of Texas at El Paso 500 West University El Paso TX 79968-0521 United States of America

There exist two general approaches to solve multiple objective problems. The first approach involves the aggregation of all the objective functions into a single composite objective function. Mathematical methods such as the weighted sum method, goal programming, or utility functions are methods that pertain to this general approach. The output of this method is a single solution. On the other hand, we have the multiple objective evolutionary algorithms that offer the decision maker a set of trade off solutions usually called non dominated solutions or, Pareto-optimal solutions. This set is usually very large and the decision maker faces the problem of reducing the size of this set to have a manageable number of solutions to analyze. This paper presents a post- Pareto approach to prune the non-dominated set of solutions obtained by multiple objective evolutionary algorithms. The proposed approach uses a non-uniform weight generator method to reduce the size of the Pareto-optimal set. A pair of examples is presented to show the performance of the method.

关键词： post-Pareto optimality decision making multi-objective optimization problems

来源：评论

学校读者我要写书评

暂无评论

A General Iterative Procedure of the Non-Numerical Ranking Preferences Method for Multiple Objective Decision Making

引用

Procedia Computer science 2012年 12卷 135-139页

作者： Victor M. Carrillo Heidi Taboada Computational Science Program. The University of Texas at El Paso 500 West University Av El Paso TX 79968-0521 United States of America Department of Industrial Manufacturing and Systems Engineering. The University of Texas at El Paso 500 West University Av El Paso TX 79968-0521 United States of America

Multiple objective evolutionary algorithms (MOEAs), which are biologically-inspired optimization methods, have become popular approaches to solve problems with multiple objective functions. With the use of MOEAs, multiple objective optimization becomes a two-part problem. First, the multiple objective optimization problem needs to be formulated and successfully solved using an MOEA. Then, a non- dominated set -also known as efficient or Pareto frontier- needs to be analyzed to select a solution to the problem. This can represent a challenging task to the decision-maker because this set can contain a large number of solutions. This decision- making stage is usually known as the post-Pareto analysis stage. This paper presents the generalization of a post-Pareto optimality method known as the non-numerical ranking preferences (NNRP) method originally proposed by Taboada et al . (2007). This method can help decision makers reduce the number of design possibilities to small subsets that clearly reflect their objective function preferences. Previous research has only presented the application of the NNRP method using three and four objective functions but had not been generalized to the case of n objective functions. The present paper expands the NNRP method to be able to consider multiple objective optimization problems with n number of objective functions.

关键词： post-Pareto optimality decision making multi-objective optimization

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：