No description available.

Polymer Light-Emitting Electrochemical Cells (PLECs) are solid state devices based on the in situ electrochemical doping of the luminescent polymer and the formation of a p-n junction where light is emitted upon the application of a bias current or voltage. PLECs answer the drawbacks of polymer light-emitting diodes as they do not require an ultra-thin active layer nor are they reliant on low work function cathode materials that are air unstable. However, because of the dynamic nature of the doping, they suffer from slow response times and poor stability over time. Frozen-junction PLECs offer a solution to these drawbacks, yet they are impractical due to their sub-ambient operation temperature requirement. Our work presented henceforth aims to achieve room temperature frozen-junction PLECS. In order to do that we removed the ion solvating/transporting polymer from the active layer, resulting in a luminescent polymer combined solely with a salt sandwiched between an ITO electrode and an aluminum electrode. The resulting device was not expected to operate like a PLEC due to the absence of an ion-solvating and ion-transporting medium. However, we discovered that the polymer/salt devices could be activated by applying a large voltage bias, resulting in much higher current and luminance. More important, the activated state is quasi static. Devices based on the well-known orange-emitting polymer MEH-PPV displayed a luminance storage half-life of 150 hours when activated by forward bias (ITO biased positively with respect to the aluminum) and 200 hours when activated by reverse bias. More remarkable yet, devices based on a green co-polymer displayed no notable decay in current density or luminance even after being stored for 1200 hours at room temperature! PL imaging under UV excitation demonstrates the presence of doping. These devices are described herein along with an explanation of their operating mechanisms. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-11-29 17:40:19.152

The operating room (OR) is an area of particularly high risk for patients, due to technical and non-technical issues. Research in other high-risk industries has shown that leadership can impact safety and performance of work teams. As the leader of the surgical team, surgeons must demonstrate leadership along with technical excellence, to optimize performance and maximize patient safety in the OR. This thesis investigated surgeons’ leadership in the intraoperative period. A review of the surgical literature revealed ten empirical articles examining surgeon leadership. Of these, two articles linked leadership was an outcome measure. A preliminary taxonomy that included seven elements of leadership was developed based on definitions of leadership from the literature. To further investigate intraoperative leadership, observations (<i>n</i>=29) were conducted in three hospitals in Scotland across different types of surgery. Leadership was described in detail according to the leadership elements. Surgeons engaged in significantly more leadership during more complex operations. Ten focus groups with different members of the OR team were conducted to finalize the taxonomy. The final taxonomy, the Surgeons’ Leadership Inventory (SLI), was revised to include eight elements: maintaining standards making decisions, managing resources, directing, training, communicating, supporting others, and coping with pressure. The SLI was used with adequate reliability to code videos (<i>n</i>=29) of live operations. Elements of surgeons’ leadership differed before and after the surgical point of no return. Analysis revealed differences in training and supporting others behaviours in cases with an unexpected event. The element coping with pressure was significantly related to intraoperative blood loss. Surgeons’ intraoperative leadership was found to be reactive, situation based, and often transactional in nature. This thesis provides a first step in identifying the important behaviours and a basis on which improving surgeons’ intraoperative leadership may be made.

De nos jours, la réalisation d'un projet de grande ampleur implique toujours une notion de travail d'équipe. Depuis plusieurs années, nous assistons donc à une demande croissante en termes d'outils informatiques pour assister les activités collaboratives. Les solutions les plus abouties à ce jour sont les environnements virtuels collaboratifs (CVE). L'utilisation de ces outils reste cependant marginale en raison de la dimension " distante " de la collaboration qu'ils proposent : en situation réelle, les participants sont, dans la plupart des cas, situés au même endroit. Cette situation porte le nom de " colocalisation ". Les grandes structures adoptent une méthode de travail colocalisé appelée " war room " : un espace physique multi-surfaces permettant un travail simultané et non-linéaire. Les travaux présentés dans cette thèse visent à proposer une plateforme matérielle et logicielle plus proche des besoins d'une équipe colocalisée, et focalisée sur le travail de revue de projet autour de maquettes numériques 3D. Après une analyse de la notion d'espace et des comportements sociaux et cognitifs des individus en situation de colocalisation, nous proposons une plateforme informatisée s'inspirant de la dynamique d'une War room. Nous mettons en particulier l'accent sur la diversité des compétences des utilisateurs en implémentant un système de " canaux d'interaction/visualisation " offrant des perceptions hétérogènes du même objet virtuel dans la war room. Ce travail est complété par la définition d'un moyen de transformer une plateforme CVE classique (SPIN|3D) pour la rendre compatible avec le travail en war room. Cette transformation repose notamment sur l'insertion de plusieurs degrés d'abstraction de données dans une architecture que nous appelons MnVO. La plateforme résultante a été mise en application sous la forme de deux prototypes : le premier propose un scenario de collaboration distribuée autour d'une voiture virtuelle. Le second s'appuie sur le système de canaux pour fournir un scénario de revue de projet d'urbanisme. / Performing a large scale job always involves some teamwork. Therefore, for several years, there has been a growing need regarding computer assistance for this kind of collaborative task. The most complete solutions existing today are collaborative virtual environments (CVE). However, the use of these tools is still uncommon because of the "distant" aspect of the collaboration in CVEs: In a real use case, co-workers are mostly located in the same place. Such a situation is called "colocation". Therefore, large companies choose another working method called "war room": a physical space allowing simultaneous and non-linear work using multiple working surfaces. This thesis aims at providing a hardware and software platform dedicated to collocated collaboration and focused on project review activities. After having analyzed the notion of space, and observed socio-cognitive behavior of collocated coworkers, we present a computer-aided platform inspired from war rooms. This work emphasizes on the users' competence diversity by implementing a paradigm called "channels". These channels offer multiple heterogeneous representations of virtual objects in the war room. This work is completed by the definition of a method for changing a classical CVE platform (SPIN|3D) into a computer-supported war room. This transformation involves notably the insertion of several abstraction levels for data; thanks to software architecture we call MnVO. The resulting platform is finally used for two prototypes: The first one provides distributed collaboration activity upon a virtual vehicle. The second one relies on the channels technology and provides an urbanism project review scenario.

An experimental study of fire testing of solid materials has been carried out to investigate whether or not these tests yield useful data for the burning of materials stored in bulk, for example in warehouses. Tests were performed using the Cone Calorimeter, the HSE third scale room/corridor rig, BS 5852 part 2, and some nonstandard tests. The results have been compared and the problems with fire testing have been discussed with reference to the current literature and trends in fire testing. The additional complications of unusual material behaviour under exposure to heating have also been investigated. In the third scale room/corridor test, where vertical, parallel samples are used, the separation distance between the samples was found to play a significant part in whether ignition of fire retarded samples could be achieved or not. A literature survey revealed a dearth of information on this subject. As this type of parallel configuration is found in warehouse storage as well as vertical ducts and cavities, an investigation was conducted into flames between vertical parallel walls. Measurements were made of total and radiative heat fluxes at the walls, flame and gas temperatures, and flame heights under a variety of conditions. It was found that the configuration of the system was very important, with the separation distance and fluid dynamics both having a major influence. Burner position, geometry and heat release rate were also varied and their influence assessed. Statistical methods were employed to correlate the heat flux data and temperatures with the other variables, with excellent correlation coefficients for the equations developed. These have been compared with previous expressions developed for flames against vertical walls. Results from CFD work on two of the parallel wall cases of special interest were analysed and discussed with reference to the . experimental results. The findings have implications for the fire testing of materials, and for the hazard assessment of materials stored in high rack storage. An understanding of potential exposure conditions in a real fire scenario are essential for the appropriate use of fire tests.

This thesis is a part of a research project performed by two MS students, Zhouchi Li and the author. The overall objective of the project is the design, implementation and performance evaluation of algorithms for newborns localization and tracking in hospitals using Apple iBeacon technology. Although we were working on the project together, I lead performance evaluation of the in-room localization system using Cramer Rao Lower Bound (CRLB). My partner, Zhouchi Li, leads modeling the path-loss of iBeacons and presence detection algorithms. This thesis describes the project with a focus on my individual contributions in CRLB analysis under different iBeacon deployment patterns as well as performance evaluation using practical characteristics of shadow fading. Today, Wi-Fi localization is the most popular indoor localization technique, which provides an accuracy of a few meters to distinguish the presences in different rooms of a building. With the recent introduction of iBeacon by Apple, possibility of more accurate in-room localization has emerged for specific applications such as locating newborns inside a hospital. The iBeacon uses Bluetooth Low Energy (BLE) technology that broadcasts beacons with unique information to the nearby receivable devices such as iPhone and android smart phones. The RSS of these beacons can be used to estimate the location and to construct an in-room localization system. In this thesis, we investigate in-room localization system using iBeacon for the newborns in hospitals with an accuracy of about 1 meter. We firstly present an in-room localization system using RSS from iBeacon. Then, based on the traditional Cramer-Rao Lower Bound (CRLB) we analyze the optimal deployment strategy for different iBeacon deployment patterns in the nursery room. Finally, we introduce a novel approach for calculation of the CRLB which includes practical conditions to analyze the influence of variable variance of shadow fading and coverage probability.

This thesis is a part of a research project performed by two MS students Yang Yang and the author. The overall objective of the project is the design, implementation, and performance evaluation of algorithms for newborn localization and tracking in hospitals using Apple iBeacon technology. In the research project, I lead the path-loss modeling of iBeacon, design of algorithms for in-room presence detection system, and analysis of the accelerometer sensor. My partner, Yang Yang, leads the performance evaluation of the localization system using Cramer Rao Lower Bound (CRLB). This manuscript describes the project with a focus on my contributions in modeling the behavior of sensors and presence detection algorithms. Today, RFID detection is the most popular indoor detection technique. It provides high precision detection rate to distinguish the number of people in certain rooms of a building. However, special scanners and manual operations are required. This increases the cost and operation complexity. With the recent introduction of iBeacon by Apple, possibility of more efficient in-room presence detection has emerged for specific applications. An example of these applicatons is recording the number of visitors and newborns in a nursery room inside a hospital. The iBeacon uses Bluetooth Low Energy (BLE) technology for proximity broadcasting. Additionally, iBeacon carries a motion detection sensor, which can be utilized for counting the number of people and newborns entering and leaving a room. In this thesis we introduce a novel intelligent in-room presence detection system using iBeacon for the newborns in hospitals to determine the number of visitors and newborns' location in the nursery room. We first develop a software application on iPhone to receive and extract the necessary data from iBeacon for further analysis. We build the path-loss model for the iBeacon based on the received signal strength (RSS) of the iBeacon, which is used for performance evaluation using CRLB in Yang Yang's project. We also utilize the accelerometer in the smart phones to improve the performance of our detection system.

PURPOSE: The aim of this study is to better characterize the effect of the interval in time to the operating room on hospital length of stay and other post-surgical outcomes in adult patients with common emergency general surgery conditions who are admitted to the acute care surgical service at Boston Medical Center. METHODS: This is retrospective cohort study examining a total of 321 subjects taken from an emergency general surgery registry at Boston Medical Center from May 2014 thru May 2015. Variables analyzed included: demographic factors, Charlson Comorbidity Index scores, times to the operating room, hospital length of stays, post- operative complications, and in-hospital mortality. RESULTS: There were zero mortalities in this study and a 3.1% post-operative complication rate. There was a positive association between time to the operating room and hospital length of stay, even after controlling for covariates. It was found that those subjects who go to the operating room after 6 hours from the time of admission have an increased hospital length of stay by about 12 hours as compared to those subjects who do not. CONCLUSIONS: In this study, subjects who went to the operating room sooner from the time of admission had associated shorter hospital length of stays and fewer post- operative complications.

Taking into consideration the existing financial crisis in Spain and the opportunity it carries for real estate agents and rooms/apartments owners to rent out their properties, roomsDB.net propose to launch a new room rental website to take advantage of the current niche existing in Madrid, Spain. The management team have direct knowledge of developing and running a successful room rental website in Singapore with six years of experience. In the big market of real estate we determined that the best option for us in Madrid is non-luxury apartments/rooms. We are confident that we are not going to find fierce competition in the medium-term and we will take advantage of this to become the leaders in this segment of the market. Moreover, some of the current competitors do not have the option for agents to post their offers in their websites and we do will offer this service. The website will be different from competitors in customer oriented service, user friendly platform, immediate response to enquiries as well as achieving a lower cost base. The promoters plan to raise an initial €60,000 to launch the website with a forecast of obtaining the 25% of the market share in the industry in Madrid. Based on case scenarios forecast, the website is forecast to generate cash from the first year of operation and the business will be also cash generative from the same year. The attached case scenario forecasts show a rapid growth and producing attractive returns. By year five, the return on investment is 55 per cent.

The link to subjective parameters and objective parameters in the field of room acoustics has been the source of much research. This thesis surveys some of the available objective room acoustical analysis methods, quantify their advantages and disadvantages with respect to the measurement of acoustical qualities of professionally operated critical listing rooms, and implements these methods in a range of critical listening rooms. In conjunction with the objective room analysis, a subjective component of research was also performed. A series of anechoically recorded standard instrument sounds were presented to professional listeners in their critical listening spaces with the listeners asked to alter the sounds to taste: to