A Constitutive Model for Overconsolidated Structured Soils Using Structural Variable

Due to the influence of soil structure, structured soils exhibit significantly different mechanical behavior compared to the reconstituted soils having the same material. In this work, a theoretical analysis focusing on the mechanical behavior of structured soils is presented. Based on the mechanical behavior of the structured soil, a newly defined variable structural index was used as a measurement of the integrity of soil structure based on the concept of intrinsic compression line of intact structured soils. Furthermore, a novel correlation for the variation in volume of structured soils is established using effective stress and newly defined structural index as the constitutive variables. The novel correlation provided interpretation about the mechanism of compression behavior of the structured soils. Afterwards, the proposed correlation for the variation in volume was extended to triaxial stress state in the framework of subloading surface to include the effect of overconsolidation. Comparisons between the predictions and experimental results validated the proposed constitutive model for structured soils.

Research on the Tensile Properties of Microcellular PS with Supercritical CO2

Separating the influence of relative density and cell diameter on the tensile properties is very important to the theory research on mechanic properties of microcellular foamed materials. In this article, differences of the influences of relative density and cell diameter on the tensile properties are identified by the foaming PS in constrained mold. The effects of relative density and foaming process conditions such as foaming temperature, foaming time and saturated pressure on the tensile strength and Youngs modulus are analyzed. The results show that relative density is the only structural variable of Youngs modulus and Youngs modulus is not relative to cell diameter. Youngs modulus is in proportion to relative density. Tensile stress of microcellular PS is in contrast to cell diameter, decreases with increasing foaming time and foaming temperature and increases with saturated pressure.

Environmental And Structural Influences On The Strategy-Making Process Of Banks

This study investigated the effects of perceived environmental dynamism, heterogeneity, and resource munificence, as well as two structural characteristicsformalization and centralizationon the strategy-making variables of assertiveness and rationality. Finding from 59 banks indicated that perceived environmental heterogeneity and munificence were both positively related to the assertiveness and rationality of strategy-making, whereas perceived dynamism was negatively related to rationality. Formalization, a structural variable, was found to contribute the most to strategy-making.

Nurse Dose: Validation and Refinement of a Concept

In this article, we report the results of two studies aimed at validating the concept of nurse dose. The first study examined the relevance of the critical attributes and empirical indicators in accurately reflecting the concept of nurse dose. Ten experts in staffing research rated the relevance of the attributes and indicators. The second study explored the factorial structure of the nurse dose concept. Data on the nurse dose indicators were obtained from 26 inpatient units. The operationalization of nurse dose was refined based on the two studies’ results. Nurse dose is posited as a structural variable capturing nurses’ capacity to deliver high quality care in acute care hospitals. It is defined as the level (i.e., number and type) of nursing staff required to provide care that produces intended patient outcomes. Nurse dose is reflected in two attributes: (1) active ingredients representing the essential elements that distinguish nurses from other health care professionals and operationalized in nurses’ theoretical and practical knowledge, and skill mix; and (2) intensity representing the potential for nurse–patient interactions and operationalized in terms of amount (indicated by full-time equivalent) and frequency (indicated by nurse–patient ratio and hours per patient day). The concept of nurse dose has the potential for guiding future staffing research.