The design, kinematics and torque analysis of the self-bending soft contraction actuator

This article presents the development of a self-bending contraction actuator (SBCA) through analysis of its structure, kinematics, and torque formulas, and then explores its applications. The proposed actuator has been fabricated by two methods to prove the efficiency of the human body inspiration, which represents the covering of human bones by soft tissues to protect the bone and give the soft texture. The SBCA provides bending behaviour along with a high force to-weight ratio. As with the simple pneumatic muscle actuator (PMA), the SBCA is soft and easy to implement. Both the kinematics and the torque formula presented for the SBCA are scalable and can be used with different actuator sizes. The bending actuator has been tested under an air pressure up to 500 kPa, and the behaviour of its bending angle, parameters, dimensions, and the bending torques have been illustrated. On the other hand, the experiments showed the efficient performances of the actuator and validate the proposed kinematics. Therefore, the actuator can be used in many different applications, such as soft grippers and continuum arms

Evaluating The International Diversification Benefits Of Chinas New Indexes

This article examines the characteristics and performance of selected Chinas financial indexes. Although several indexes were recently made available, this study focuses on three in particular because they are compiled using distinct methodologies. Based on the differences in their composition, they were categorized as either global or investable indexes, herein indexes composed of shares that are readily available for trading in the market. From a portfolio diversification perspective, this study found that U.S. investors seeking exposure to China stand to gain the most from funds tracking the Standard & Poors/CITIC 50 Index (a global index) than from those tracking the FTSE/Xinhua China 25 Indexor the Halter USX China Index (investable indexes). Its risk-return characteristics, along with other performance evaluation measures used, show that it is most efficient in providing international diversification benefits

Perspective distortion modeling for image measurements

A perspective distortion modelling for monocular view that is based on the fundamentals of perspective projection is presented in this work. Perspective projection is considered to be the most ideal and realistic model among others, which depicts image formation in monocular vision. There are many approaches trying to model and estimate the perspective effects in images. Some approaches try to learn and model the distortion parameters from a set of training data that work only for a predefined structure. None of the existing methods provide deep understanding of the nature of perspective problems. Perspective distortions, in fact, can be described by three different perspective effects. These effects are pose, distance and foreshortening. They are the cause of the aberrant appearance of object shapes in images. Understanding these phenomena have long been an interesting topic for artists, designers and scientists. In many cases, this problem has to be necessarily taken into consideration when dealing with image diagnostics, high and accurate image measurement, as well as accurate pose estimation from images. In this work, a perspective distortion model for every effect is developed while elaborating the nature of perspective effects. A distortion factor for every effect is derived, then followed by proposed methods, which allows extracting the true target pose and distance, and correcting image measurements

Reevaluating Portfolio Diversification Benefits With New Multinational Indices

This study reviews international diversification using new sets of global and regional indices of multinational companies. Contrary to previous studies, it can be demonstrated that U.S. investors can aspire to strategically balanced portfolios through positioning in these indices. On might think that, because U.S.- and European -based companies frequently dominate these indices this might lead to poor diversification benefits. After all, one could argue that policymakers from the U.S. and the other major economies are increasingly coordinating their macroeconomic decisions resulting in the same monetary and public policies that affect a portfolio of purely domestic firms. Our results, however, show that it is far from being the case

Microparticles are vectors of paradoxical information in vascular cells including the endothelium: role in health and diseases

Both inflammation and thrombosis can be orchestrated by the interactions between circulating cells, such as leukocytes and platelets, with vascular, endothelial and smooth muscle cells, which, during activation or apoptosis, can release circulating microparticles (MPs). Indeed, MPs are membrane vesicles with procoagulant and proinflammatory properties. MPs are present in blood from healthy individuals and in patients under several pathological states, for instance sepsis, preeclampsia, Crohn\u27s disease and diabetes, strengthening the notion that MPs may play a role in these diseases. Circulating MPs or those generated in vitro from apoptotic T cells display deleterious effects on endothelial and/or vasomotor function. In contrast, MPs might be protective to endothelial cells. We have shown that MPs harboring the morphogen sonic hedgehog may represent a new therapeutic approach against endothelial dysfunction during acute severe endothelial injury. Indeed, these types of MPs induce NO release, decrease production of reactive oxygen species and induce angiogenesis from endothelial cells. This protective role for the endothelium was confirmed also by their in vivo injection in mice in which they were also able to reverse endothelial dysfunction in a model of heart ischemia/reperfusion. On the contrary, MPs from preeclamptic women compared to those from normal pregnant women showed pro-inflammatory properties in the vascular wall inducing vascular hyporeactivity in vessels from humans and mice. These effects were associated with complex interactions between NO and cyclooxygenase systems via endothelial cell activation. Altogether, these findings suggest that MPs can be considered as vectors of biological messages for vascular homeostasis, during immunity and inflammation

State estimation in quantum homodyne tomography with noisy data

In the framework of noisy quantum homodyne tomography with efficiency parameter $0 < \eta \leq 1$, we propose two estimators of a quantum state whose density matrix elements $\rho_{m,n}$ decrease like $e^{-B(m+n)^{r/ 2}}$, for fixed known $B>0$ and $0<r\leq 2$. The first procedure estimates the matrix coefficients by a projection method on the pattern functions (that we introduce here for $0<\eta \leq 1/2$), the second procedure is a kernel estimator of the associated Wigner function. We compute the convergence rates of these estimators, in $\mathbb{L}_2$ risk