Social and commercial entrepreneurship: same, different, or both?

Entrepreneurship has been the engine propelling much of the growth of the business sector as well as a driving force behind the rapid expansion of the social sector. This article offers a comparative analysis of commercial and social entrepreneurship using a prevailing analytical model from commercial entrepreneurship. The analysis highlights key similarities and differences between these two forms of entrepreneurship and presents a framework on how to approach the social entrepreneurial process more systematically and effectively. We explore the implications of this analysis of social entrepreneurship for both practitioners and researchers.

An Interval Intelligent-based Approach for Fault Detection and Modelling

Not considered in the analytical model of the plant, uncertainties always dramatically decrease the performance of the fault detection task in the practice. To cope better with this prevalent problem, in this paper we develop a methodology using Modal Interval Analysis which takes into account those uncertainties in the plant model. A fault detection method is developed based on this model which is quite robust to uncertainty and results in no false alarm. As soon as a fault is detected, an ANFIS model is trained in online to capture the major behavior of the occurred fault which can be used for fault accommodation. The simulation results understandably demonstrate the capability of the proposed method for accomplishing both tasks appropriately

Hacia un modelo de análisis de políticas públicas operativ : Un enfoque basado en los actores, sus recursos y las instituciones

Towards an operative analysis of public policies: An approach focused on actors, resources and institutions. This article develops an analytical model which is centred on the individual and collective behaviour of actors involved during different stages of public policy. We postulate that the content and institutional characteristics of public action (dependent variable) are the result of interactions between political-administrative authorities, on the one hand, and, on the other, social groups which cause or suffer the negative effects of a collective problem which public action attempts to resolve (independent variables). The 'game' of the actors depends not only on their particular interests, but also on their resources (money, time, consensus, organization, rights, infrastructure, information, personnel, strength, political support) which they are able to exploit to defend their positions, as well as on the institutional rules which frame these policy games.

Nanoscale capacitance microscopy of thin dielectric films

We present an analytical model to interpret nanoscale capacitance microscopy measurements on thin dielectric films. The model displays a logarithmic dependence on the tip-sample distance and on the film thickness-dielectric constant ratio and shows an excellent agreement with finite-element numerical simulations and experimental results on a broad range of values. Based on these results, we discuss the capabilities of nanoscale capacitance microscopy for the quantitative extraction of the dielectric constant and the thickness of thin dielectric films at the nanoscale.

Micro-Raman study of stress distribution in local isolation structures and correlation with transmission electron microscopy

Stress in local isolation structures is studied by micro‐Raman spectroscopy. The results are correlated with predictions of an analytical model for the stress distribution and with cross‐sectional transmission electron microscopy observations. The measurements are performed on structures on which the Si3N4 oxidation mask is still present. The influence of the pitch of the periodic local isolation pattern, consisting of parallel lines, the thickness of the mask, and the length of the bird"s beak on the stress distribution are studied. It is found that compressive stress is present in the Si substrate under the center of the oxidation mask lines, with a magnitude dependent on the width of the lines. Large tensile stress is concentrated under the bird"s beak and is found to increase with decreasing length of the bird"s beak and with increasing thickness of the Si3N4 film.

Analysis of the role of mobility-lifetime products in the performance of amorphous silicon p-i-n solar cells

An analytical model of an amorphous silicon p-i-n solar cell is presented to describe its photovoltaic behavior under short-circuit conditions. It has been developed from the analysis of numerical simulation results. These results reproduce the experimental illumination dependence of short-circuit resistance, which is the reciprocal slope of the I(V) curve at the short-circuit point. The recombination rate profiles show that recombination in the regions of charged defects near the p-i and i-n interfaces should not be overlooked. Based on the interpretation of the numerical solutions, we deduce analytical expressions for the recombination current and short-circuit resistance. These expressions are given as a function of an effective ¿¿ product, which depends on the intensity of illumination. We also study the effect of surface recombination with simple expressions that describe its influence on current loss and short-circuit resistance.

The 2006 Eiger rockslide, European Alps

In July 2006, approximately 2 million m3 of massive limestone began to move on the east flank of the Eiger in central Switzerland. For more than two years after the initial failure, the rock mass moved at rates of up to 70 cm per day. A detailed analysis of the structures and velocities of the different moving blocks was conducted with the aid of terrestrial laser scanning. The moving rock mass included a rear block that subsided, pushing a frontal block forward. Movement directions were controlled by discontinuity sets that formed wedges bounded on one side by sub-vertical bedding planes. The instability was, until recently, buttressed by a glacier. Slope observations and results of continuum and discontinuum modeling indicate that the structure of the rock mass and topography were the main causes of the instability. Progressive weathering and mechanical fatigue of the rock mass appear to have led to the failure. A dynamic analytical model further indicates that the rockslide was primarily controlled by a reduction in the strength of discontinuities, the effects of ice deformation, and ? to a limited extent ? groundwater flow. This study shows that realistic and simple instability models can be constructed for rock-slope failures if high-resolution data are available.

Unraveling dynamics of human physical activity patterns in chronic pain conditions.

Chronic pain is a complex disabling experience that negatively affects the cognitive, affective and physical functions as well as behavior. Although the interaction between chronic pain and physical functioning is a well-accepted paradigm in clinical research, the understanding of how pain affects individuals' daily life behavior remains a challenging task. Here we develop a methodological framework allowing to objectively document disruptive pain related interferences on real-life physical activity. The results reveal that meaningful information is contained in the temporal dynamics of activity patterns and an analytical model based on the theory of bivariate point processes can be used to describe physical activity behavior. The model parameters capture the dynamic interdependence between periods and events and determine a 'signature' of activity pattern. The study is likely to contribute to the clinical understanding of complex pain/disease-related behaviors and establish a unified mathematical framework to quantify the complex dynamics of various human activities.

Demonstration of Load Rating Capabilities through Physical Load Testing: Sioux County Bridge Case Study, RB32-013, 2013

The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of performing such testing, and perform outreach to local, state, and national engineers on the topic of bridge load testing and rating. This report documents one of three bridges inspected, load tested, and load rated as part of the project, the Sioux County Bridge (FHWA #308730), including testing procedures and performance of the bridge under static loading along with the calculated load rating from the field-calibrated analytical model. Two parallel reports document the testing and load rating of the Ida County Bridge (FHWA #186070) and the Johnson County Bridge (FHWA #205750). A tech brief provides overall information about the project.

Demonstration of Load Rating Capabilities through Physical Load Testing: Ida County Bridge Case Study, RB32-013, 2013

The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of performing such testing, and perform outreach to local, state, and national engineers on the topic of bridge load testing and rating. This report documents one of three bridges inspected, load tested, and load rated as part of the project, the Ida County Bridge (FHWA #186070), including testing procedures and performance of the bridge under static loading along with the calculated load rating from the field-calibrated analytical model. Two parallel reports document the testing and load rating of the Sioux County Bridge (FHWA #308730) and the Johnson County Bridge (FHWA #205750). A tech brief provides overall information about the project.

Demonstration of Load Rating Capabilities through Physical Load Testing: Johnson County Bridge Case Study, RB32-013, 2013

The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of performing such testing, and perform outreach to local, state, and national engineers on the topic of bridge load testing and rating. This report documents one of three bridges inspected, load tested, and load rated as part of the project, the Johnson County Bridge (FHWA #205750), including testing procedures and performance of the bridge under static loading along with the calculated load rating from the field-calibrated analytical model. Two parallel reports document the testing and load rating of the Sioux County Bridge (FHWA #308730) and the Ida County Bridge (FHWA #186070). A tech brief provides overall information about the project.

Demonstration of Load Rating Capabilities through Physical Load Testing (4 vol), RB32-013, 2013

The objective of this work, Pilot Project - Demonstration of Capabilities and Benefits of Bridge Load Rating through Physical Testing, was to demonstrate the capabilities for load testing and rating bridges in Iowa, study the economic benefit of performing such testing, and perform outreach to local, state, and national engineers on the topic of bridge load testing and rating. The three final reports document one each of three bridges inspected, load tested, and load rated as part of the project. The bridges include the Sioux County Bridge (FHWA #308730), the Ida County Bridge (FHWA #186070), and the Johnson County Bridge (FHWA #205750). Actions included testing procedures and performance of the bridge under static loading along with the calculated load rating from the field-calibrated analytical model. A Tech Transfer Summary provides overall information about the project.

Strengthening of Existing Single Span Steel Beam and Concrete Deck Bridges, HR-238, Part II, 1985

The unifying objective of Phases I and II of this study was to determine the feasibility of the post-tensioning strengthening method and to implement the technique on two composite bridges in Iowa. Following completion of these two phases, Phase III was undertaken and is documented in this report. The basic objectives of Phase III were further monitoring bridge behavior (both during and after post-tensioning) and developing a practical design methodology for designing the strengthening system under investigation. Specific objectives were: to develop strain and force transducers to facilitate the collection of field data; to investigate further the existence and effects of the end restraint on the post-tensioning process; to determine the amount of post-tensioning force loss that occurred during the time between the initial testing and the retesting of the existing bridges; to determine the significance of any temporary temperature-induced post-tensioning force change; and to develop a simplified design methodology that would incorporate various variables such as span length, angle-of-skew, beam spacing, and concrete strength. Experimental field results obtained during Phases II and III were compared to the theoretical results and to each other. Conclusions from this research are as follows: (1) Strengthening single-span composite bridges by post-tensioning is a viable, economical strengthening technique. (2) Behavior of both bridges was similar to the behavior observed from the bridges during field tests conducted under Phase II. (3) The strain transducers were very accurate at measuring mid-span strain. (4) The force transducers gave excellent results under laboratory conditions, but were found to be less effective when used in actual bridge tests. (5) Loss of post-tensioning force due to temperature effects in any particular steel beam post-tensioning tendon system were found to be small. (6) Loss of post-tensioning force over a two-year period was minimal. (7) Significant end restraint was measured in both bridges, caused primarily by reinforcing steel being continuous from the deck into the abutments. This end restraint reduced the effectiveness of the post-tensioning but also reduced midspan strains due to truck loadings. (8) The SAP IV finite element model is capable of accurately modeling the behavior of a post-tensioned bridge, if guardrails and end restraints are included in the model. (9) Post-tensioning distribution should be separated into distributions for the axial force and moment components of an eccentric post-tensioning force. (10) Skews of 45 deg or less have a minor influence on post-tensioning distribution. (11) For typical Iowa three-beam and four-beam composite bridges, simple regression-derived formulas for force and moment fractions can be used to estimate post-tensioning distribution at midspan. At other locations, a simple linear interpolation gives approximately correct results. (12) A simple analytical model can accurately estimate the flexural strength of an isolated post-tensioned composite beam.

Factors associated with healthcare professionals' intent to stay in hospital: a comparison across five occupational categories.

OBJECTIVE: To identify factors associated with intent to stay in hospital among five different categories of healthcare professionals using an adapted version of the conceptual model of intent to stay (CMIS). DESIGN: A cross-sectional survey targeting Lausanne University Hospital employees performed in the fall of 2011. Multigroup structural equation modeling was used to test the adapted CMIS model among professional groups. Measures Satisfaction, self-fulfillment, workload, working conditions, burnout, overall job satisfaction, institutional identification and intent to stay. PARTICIPANTS: Surveys of 3364 respondents: 494 physicians, 1228 nurses, 509 laboratory technicians, 935 administrative staff and 198 psycho-social workers. RESULTS: For all professional categories, self-fulfillment increased intent to stay (all β > 0.14, P < 0.05). Burnout decreased intent to stay by weakening job satisfaction (β < -0.23 and β > 0.22, P < 0.05). Some factors were associated with specific professional categories: workload was associated with nurses' intent to stay (β = -0.15), and physicians' institutional identification mitigated the effect of burnout on intent to stay (β = -0.15 and β = 0.19). CONCLUSION: Respondents' intent to stay in a position depended both on global and profession-specific factors. The identification of these factors may help in mapping interventions and retention plans at both a hospital level and professional groups' level.

A two-phase composite in simple shear: Effective mechanical anisotropy development and localization potential

We present a combined shape and mechanical anisotropy evolution model for a two-phase inclusion-bearing rock subject to large deformation. A single elliptical inclusion embedded in a homogeneous but anisotropic matrix is used to represent a simplified shape evolution enforced on all inclusions. The mechanical anisotropy develops due to the alignment of elongated inclusions. The effective anisotropy is quantified using the differential effective medium (DEM) approach. The model can be run for any deformation path and an arbitrary viscosity ratio between the inclusion and host phase. We focus on the case of simple shear and weak inclusions. The shape evolution of the representative inclusion is largely insensitive to the anisotropy development and to parameter variations in the studied range. An initial hardening stage is observed up to a shear strain of gamma = 1 irrespective of the inclusion fraction. The hardening is followed by a softening stage related to the developing anisotropy and its progressive rotation toward the shear direction. The traction needed to maintain a constant shear rate exhibits a fivefold drop at gamma = 5 in the limiting case of an inviscid inclusion. Numerical simulations show that our analytical model provides a good approximation to the actual evolution of a two-phase inclusion-host composite. However, the inclusions develop complex sigmoidal shapes resulting in the formation of an S-C fabric. We attribute the observed drop in the effective normal viscosity to this structural development. We study the localization potential in a rock column bearing varying fraction of inclusions. In the inviscid inclusion case, a strain jump from gamma = 3 to gamma = 100 is observed for a change of the inclusion fraction from 20% to 33%.