Efficient numerical integration of an elastic–plastic damage law within a mixed velocity–pressure formulation

This study focuses on numerical integration of constitutive laws in numerical modeling of cold materials processing that involves large plastic strain together with ductile damage. A mixed velocity–pressure formulation is used to handle the incompressibility of plastic deformation. A Lemaitre damage model where dissipative phenomena are coupled is considered. Numerical aspects of the constitutive equations are addressed in detail. Three integration algorithms with different levels of coupling of damage with elastic–plastic behavior are presented and discussed in terms of accuracy and computational cost. The implicit gradient formulation with a non-local damage variable is used to regularize the localization phenomenon and thus to ensure the objectivity of numerical results for damage prediction problems. A tensile test on a plane plate specimen, where damage and plastic strain tend to localize in well-known shear bands, successfully shows both the objectivity and effectiveness of the developed approach.     

铁路勘察设计企业编制内部定额的工作策划

结合定额的概念，针对铁路勘察设计企业编制内部定额的必要性和重要性，详细阐述了编制定额的方案、工作程序、编制原则，编制工作组织方式，所需成本，需明确条件等内容，以期帮助铁路勘察设计企业编制出准确合理的内部定额。     

Development of Oral Strips Containing Chitosan as Active Ingredient: A Product for Buccal Health

In the last years, the number of products for oral care has been expanded to adapt to consumer needs. Thus, in addition to conventional products, new “pocket products” such as sugar-free chewing gums and oral strips (OS) have been developed for oral care. In the present study, OS were formulated using chitosan as the film-forming polymer in adequate concentrations to also be used as antimicrobial agent. Other strip components, such as the type of plasticizer, were also optimized. Mechanical properties of the optimal OS were evaluated and, due to chitosan's characteristic astringency, the strips were also sensorially evaluated.     

Chick Chorioallantoic Membrane as an In Situ Biological Membrane for Pharmaceutical Formulation Development: A Review

The use of animals in research has always been a debatable issue. Over the past few decades, efforts have been made to reduce, replace, and refine experiments for ethical use of experimental animals. The use of chick chorioallantoic membrane (CAM) was one of the proposed alternatives to the Draize rabbit ocular irritation test with several advantages including simplicity, rapidity, sensitivity, ease of performance, and cost-effectiveness. The recent use of CAM in the development of pharmaceuticals and testing models to mimic human tissue, including drug transport across CAM, will be discussed in this review.     

Development of in vitro models to demonstrate the ability of PecSys®, an in situ nasal gelling technology,to reduce nasal run-off and drip

Many of the increasing number of intranasal products available for either local or systemic action can be considered sub-optimal, most notably where nasal drip or run-off give rise to discomfort/tolerability issues or reduced/variable efficacy. PecSys, an in situ gelling technology, contains low methoxy (LM) pectin which gels due to interaction with calcium ions present in nasal fluid. PecSys is designed to spray readily, only forming a gel on contact with the mucosal surface. The present study employed two in vitro models to confirm that gelling translates into a reduced potential for drip/run-off: (i) Using an inclined TLC plate treated with a simulated nasal electrolyte solution (SNES), mean drip length [±SD, n = 10] was consistently much shorter for PecSys (1.5?±?0.4?cm) than non-gelling control (5.8?±?1.6?cm); (ii) When PecSys was sprayed into a human nasal cavity cast model coated with a substrate containing a physiologically relevant concentration of calcium, PecSys solution was retained at the site of initial deposition with minimal redistribution, and no evidence of run-off/drip anteriorly or down the throat. In contrast, non-gelling control was significantly more mobile and consistently redistributed with run-off towards the throat. Conclusion: In both models PecSys significantly reduced the potential for run-off/drip ensuring that more solution remained at the deposition site. In vivo, this enhancement of retention will provide optimum patient acceptability, modulate drug absorption and maximize the ability of drugs to be absorbed across the nasal mucosa and thus reduce variability in drug delivery.     

Case formulation in EFT.

A case formulation, for a client with depression, based on emotion-focused therapy treatment principles will be presented. The client was seen for 16 sessions in emotion-focused therapy. Based on information provided in the first interview, the therapist discusses how the client’s issues can be formulated in an emotion-focused treatment by attending to different process markers, including markers of characteristic styles of being or ways of treating the self and emotional experience; modes of engagement or ways that emotional experience is processed in terms of whether it is overregulated or underregulated; specific in-session tasks like focusing, two-chair or empty chair work; and micromarkers of nonverbal behaviors including vocal quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A dynamics formulation of general constrained robots

The complexity of a standard compact-in-form Lagrangian dynamical expression is proportional to the fourth power of the number of degrees of freedom (DOF) of a robotic system. This fact challenges both simulation and control of robots with hyper degrees of freedom. In this paper, a systematic approach for deriving the dynamical expression of so-called general constrained robots is proposed. This proposed approach has two main features. First, it uses the subsystem dynamics such as the dynamics of joints and rigid links to construct the dynamical expression of the entire robotic system in a closed form. The complexity of the resulted dynamic expression is linearly proportional to the number of DOF of a robotic system. Second, it extends the standard dynamical form and properties of the conventional single-arm constrained robots to a class of more general robotic systems including the coordinated multiple-arm robotic systems. Three spaces, namely the general joint space, the general task space, and the extended subsystems space, are connected through corresponding velocity/force mapping matrices.An erratum to this article can be found at     

Co-volume method for Riemannian mean curvature flow in subjective surfaces multiscale segmentation

We introduce semi-implicit complementary volume numerical scheme for solving the level setformulation of Riemannian mean curvature flow problem arising in image segmentation, edge detection, missing boundary completion and subjective contour extraction. The scheme is robust and efficient since it is linear, and it is stable in L_∞ and weighted W ^1,1 sense without any restriction on a time step. The computational results related to medical image segmentation with partly missing boundaries and subjective contours extraction are presented.     

油气储层流动单元划分标准的探讨

根据对大量岩心样品的统计分析，研究了流动层指数(flow zone idex，Ifz)的基础定义和物理意义．结果认为：Ifz值相近的岩心样品具有较大的孔隙度和大的渗透率变化范围，但不一定属于同一类流动单元．Ifz值并不能准确的表征影响流体流动的岩石物理性质，单纯采用Ifz值作为划分储层流动单元的标准是值得商榷的．采用渗透率、层内渗透率纵向非均质参数(变异系数、突进系数、极差)、孔隙度和束缚水饱和度等参数作为标准划分流动单元并应用该方法研究了蒙古林砾岩油藏储层，结果表明：这些参数能够较为准确的描述储层内部油水运动规律相似的储集带．     

阻燃防鼠型90°CPVC电缆护套料配方研究

本文分析了电缆用阻燃防鼠型90°CPVC护套料防鼠性能及阻燃性能分别与防鼠剂用量及阻燃剂用量的关系,阻燃防鼠PVC护套料物理机械性能及电气性能与树脂、增塑剂、稳定剂、抗氧剂、填充剂等添加剂之间的关系,介绍了阻燃防鼠90°CPVC护套料配方的研制过程及配方性能。