Refugee Self Organization : The Effects of Organizations on Refugees

Abstract Refugee Self Organization: the Effects of Organizations on Refugees The following abstract will introduce research conducted to find how incoming refugees integrate themselves into American societies through the aid of organizations. The paper was divided into two main questions: 1. How do refugees self organize themselves upon arrival to a new country? 2. How do organizations help them transition into integration? The paper is serves to define ways that refugees integrate into new environments. The research was collected through conducting interviews to organizations that serve refugee communities. The findings presented in this paper were defined through a collection of the main themes from the interviews that were provided by executive directors and leaders of the five organizations. Themes such as leadership, teamwork, collaboration, and supporting and cooperative board members were derived from the interviews. Anita Fabos , Ph.D. Chief Instructor Robert Zarges, Ph.D. Assistant Professo

Human sensitivity to gearshift loads

This paper describes an investigation of the ability of humans to distinguish different levels of gearlever load. A test rig with a forward-backward moving gearshift lever was constructed using the typical interior dimensions of European B segment automobiles. The rig used a system of weights and pulleys to provide a load which could be varied in steps of 1%. Four reference loads were chosen which were considered representative of automotive gearshift operation: 0.5, 1.0, 2.0 and 5.0 kg. Twenty subjects took part in the study. Using a variation on the psychophysical method of limits, the subjects were asked to respond whether a test load was heavier or lighter than a reference load. The Weber Fraction was found to decrease monotonically from a value of 0.036 for the 0.5 kg reference load to a value of 0.029 at the 5.0 kg reference load. The average value across all reference loads was 0.032. Measurements of the gearshift force made by means of a knob containing a load cell suggested that the variation in the measured Weber Fraction might be attributable to the time behaviour of the force exchanged between the human subject and the control surface

Dynamics of a bouncing dimer

We investigate the dynamics of a dimer bouncing on a vertically oscillated plate. The dimer, composed of two spheres rigidly connected by a light rod, exhibits several modes depending on initial and driving conditions. The first excited mode has a novel horizontal drift in which one end of the dimer stays on the plate during most of the cycle, while the other end bounces in phase with the plate. The speed and direction of the drift depend on the aspect ratio of the dimer. We employ event-driven simulations based on a detailed treatment of frictional interactions between the dimer and the plate in order to elucidate the nature of the transport mechanism in the drift mode.Comment: 4 pages, 5 figures, Movies: http://physics.clarku.edu/~akudrolli/dime

Exponentially Stabilizing Controllers for Multi-Contact 3D Bipedal Locomotion

Models of bipedal walking are hybrid with continuous-time phases representing the Lagrangian stance dynamics and discrete-time transitions representing the impact of the swing leg with the walking surface. The design of continuous-time feedback controllers that exponentially stabilize periodic gaits for hybrid models of underactuated 3D bipedal walking is a significant challenge. We recently introduced a method based on an iterative sequence of optimization problems involving bilinear matrix inequalities (BMIs) to systematically design stabilizing continuous-time controllers for single domain hybrid models of underactuated bipedal robots with point feet. This paper addresses the exponential stabilization problem for multi-contact walking gaits with nontrivial feet. A family of parameterized continuous-time controllers is proposed for different phases of the walking cycle. The BMI algorithm is extended to the multi-domain hybrid models of anthropomorphic 3D walking locomotion to look for stabilizing controller parameters. The Poincaré map is addressed and a new set of sufficient conditions is presented that guarantees the convergence of the BMI algorithm to a stabilizing set of controller parameters at a finite number of iterations. The power of the algorithm is ultimately demonstrated through the design of stabilizing virtual constraint controllers for dynamic walking of a 3D humanoid model with 28 state variables and 275 controller parameters

Farklı yapıdaki kompozit rezin materyallerinin su emilimi ve suda çözünürlük değerlerinin karşılaştırılması

Purpose: The aim of the study is to investigate the physical speciality of composite resins with the water sorption and solubility test. Material and Method: With this aim, 6 kinds of composites were used like microhybrid (Venus), microfill hybrid (Gradia Direct Anterior), nanofill (Filtek Supreme) and nanohybrid composite resins (Clearfil Majesty Esthetic, Premise, Artemis). 15 samples were prepeared from each group at the standart dimensions. In the water sorption test, samples’ dried weight determined as M1. Samples were waited in pure water at 37 °C for 168 days and weight of samples were estimate with sensitive balance for 7 days period and determined as M2. M2 –M1/V formula were used to get results. In water solubility test samples’ dried weight determined as M1. Samples were waited in pure water at 37 °C for 168 days and weight of samples were estimate with sensitive balance for 7 days period and determined as M3. M3 –M1/V formula were used to get results. Data were analysed with statistically. Results: In this in vitro study; in all tests, nanofill and nanohybrid composites according to micro hybrid and microfill hybrid composites was seen statistical meaningful. Conclusion: At the result, composite resins including metacrylat group or groups, inorganic filling content, filler weight, resin matrix junctional surface affect the physical form. ÖZET Amaç: Kompozit rezinlerin fiziksel özelliklerinin; su absorbsiyonu ve çözünürlük testleri ile araştırılması amaçlanmıştır. Gereç ve yöntem: Bu amaçla klinikte kullanılmakta olan universal(Venus), mikrofil hibrit (Gradia Direct Anterior), nanofil (Filtek Supreme) ve nanohibrit kompozit rezinler (Clearfil Majesty Esthetic, Premise, Artemis) olmak üzere 6 çeşit kompozit kullanılmıştır. Her bir gruptan standart boyutlarda 15 adet örnek hazırlanmıştır. Su absorbsiyon testinde örneklerin kuru ağırlıkları M1 olarak belirlendi. Örnekler 168 gün boyunca 37°C’ de distile suda bekletildi ve 7’şer günlük periyotlarla ağırlıkları hassas terazide ölçüldü ve M2 olarak belirlendikten sonra M2–M1/V formülüne göre sonuçlar mg/mm3 olarak tespit edildi. Çözünürlük testinde örneklerin kuru ağırlıkları M1 olarak belirlendi. Örnekler 168 gün boyunca 37°C’ de distile suda bekletildi ve 7’şer günlük periyotlarla ağırlıkları hassas terazide ölçüldü ve M3 olarak belirlendikten sonra M3–M1/V formülüne göre sonuçlar mg/mm3 olarak tespit edildi. Elde edilen verilerin istatistiksel de4erlendirilmesi yapıldı. Bulgular: Yaptığımız in vitro çalışmadan elde ettiğimiz sonuçlara göre nanofil ve nano hibrit kompozitlerin tüm testlerde universal ve mikrofil hibrit kompozitlere göre istatistiksel olarak anlamlı fark oluşturduğu görülmüştür. Sonuç: Sonuç olarak; kompozit rezinlerin içerdiği metakrilat grup veya grupların, inorganik doldurucu içeriğinin, doldurucu ağırlığının, rezin matriks bağlantı yüzeyinin fiziksel yapıyı etkilediği söylenebilir. Anahtar kelimeler: Kompozit, su emilimi, suda çözünürlü

Virtual Constraints and Hybrid Zero Dynamics for Realizing Underactuated Bipedal Locomotion

Underactuation is ubiquitous in human locomotion and should be ubiquitous in bipedal robotic locomotion as well. This chapter presents a coherent theory for the design of feedback controllers that achieve stable walking gaits in underactuated bipedal robots. Two fundamental tools are introduced, virtual constraints and hybrid zero dynamics. Virtual constraints are relations on the state variables of a mechanical model that are imposed through a time-invariant feedback controller. One of their roles is to synchronize the robot's joints to an internal gait phasing variable. A second role is to induce a low dimensional system, the zero dynamics, that captures the underactuated aspects of a robot's model, without any approximations. To enhance intuition, the relation between physical constraints and virtual constraints is first established. From here, the hybrid zero dynamics of an underactuated bipedal model is developed, and its fundamental role in the design of asymptotically stable walking motions is established. The chapter includes numerous references to robots on which the highlighted techniques have been implemented.Comment: 17 pages, 4 figures, bookchapte

Estimating Dynamic Gait Stability Using Data from Non-aligned Inertial Sensors

Recently, two methods for quantifying the stability of a dynamical system have been applied to human locomotion: local stability (quantified by finite time maximum Lyapunov exponents, λs and λL) and orbital stability (quantified by maximum Floquet multipliers, MaxFm). In most studies published to date, data from optoelectronic measurement systems were used to calculate these measures. However, using wireless inertial sensors may be more practical as they are easier to use, also in ambulatory applications. While inertial sensors have been employed in some studies, it is unknown whether they lead to similar stability estimates as obtained with optoelectronic measurement systems. In the present study, we compared stability measures of human walking estimated from an optoelectronic measurement system with those calculated from an inertial sensor measurement system. Subjects walked on a treadmill at three different speeds while kinematics were recorded using both measurement systems. From the angular velocities and linear accelerations, λs, λL, and MaxFm were calculated. Both measurement systems showed the same effects of walking speed for all variables. Estimates from both measurement systems correlated high for λs and λL, (R > 0.85) but less strongly for MaxFm (R = 0.66). These results indicate that inertial sensors constitute a valid alternative for an optoelectronic measurement system when assessing dynamic stability in human locomotion, and may thus be used instead, which paves the way to studying gait stability during natural, everyday walking

High-dose chemoradiotherapy followed by surgery versus surgery alone in esophageal cancer: a retrospective cohort study

<p>Abstract</p> <p>Background</p> <p>We aimed to assess whether high-dose preoperative chemoradiotherapy (CRT) improves outcome in esophageal cancer patients compared to surgery alone and to define possible prognostic factors for overall survival.</p> <p>Methods</p> <p>Hundred-and-seven patients with disease stage IIA - III were treated with either surgery alone (n = 45) or high-dose preoperative CRT (n = 62). The data were collected retrospectively. Sixty-seven patients had adenocarcinomas, 39 squamous cell carcinomas and one undifferentiated carcinoma. CRT was given as three intensive chemotherapy courses by cisplatin 100 mg/m²on day 1 and 5-fluorouracil 1000 mg/m²/day, from day 1 through day 5 as continuous infusion. One course was given every 21 days. The last two courses were given concurrent with high-dose radiotherapy, 2 Gy/fraction and a median dose of 66 Gy. Kaplan-Meier survival analysis with log rank test was used to obtain survival data and Cox Regression multivariate analysis was used to define prognostic factors for overall survival.</p> <p>Results</p> <p>Toxicity grade 3 of CRT occurred in 30 (48.4%) patients and grade 4 in 24 (38.7%) patients of 62 patients. One patient died of neutropenic infection (grade 5). Fifty percent (31 patients) in the CRT group did undergo the planned surgery. Postoperative mortality rate was 9% and 10% in the surgery alone and CRT+ surgery groups, respectively (p = 1.0). Median overall survival was 11.1 and 31.4 months in the surgery alone and CRT+ surgery groups, respectively (log rank test, p = 0.042). In the surgery alone group one, 3 and 5 year survival rates were 44%, 24% and 16%, respectively and in the CRT+ surgery group they were 68%, 44% and 29%, respectively. By multivariate analysis we found that age of patient, performance status, alcoholism and > = 4 pathological positive lymph nodes in resected specimen were significantly associated with overall survival, whereas high-dose preoperative CRT was not.</p> <p>Conclusion</p> <p>We found no significant survival advantage in esophageal cancer stage IIA-III following preoperative high-dose CRT compared to surgery alone. Patient's age, performance status, alcohol abuse and number of positive lymph nodes were prognostic factors for overall survival.</p