991 resultados para Manned space flight


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"Whe' yu' from?" The question was put to me as I wandered, camera in hand, in the old square of Spanish Town, Jamaica's former capital. The local man, lounging in the shade of one of the colonial Georgian buildings that enclose the square, was mildly curious about what he took to be a typical white tourish photgraphing the sights of the decayed historic town. At that time, my home was in Kingston where i lived with my wife and baby son. I was then working in the Jamaican Government Town Planning Department in a job that took me all over the island. Turning to my questioner, I replied, "Kingston". There was a brief pause, and then the man spoke again: "No Man! Whe' yu' really from?" I still have difficulties when asked this question. Where am I from? What does this question mean? Does it refer to where I was born, where I spent my previous life or where I live now? Does it have a broader meaning, an enquiry about my origins in terms of background and previous experience? The following chapters are my attempt to answer these questions for my own satisfaction and, I hope, for the amusement of others who may be interested in the life of an ordinary English boy whose dream to travel and see the world was realized in ways he could not possibly have imagined. Finding an appropriate title for this book was difficult. Thursday's Child, North and South and War and Peace all came to mind but, unfortunately for me, those titles had been appropriated by other writers. Thursdays's Child is quite a popular book title, presumably because people who were born on that day and, in the words of the nursery rhyme, had 'far to go', are especially likely to have travellers' tales to tell or life stories of the rags-to-riches variety. Born on a Thursday, I have travelled a lot and I suppose that I have gone far in life. Coming from a working class family, I 'got on' by 'getting a good education' and a 'good job'. I decided against adding to the list of Thursday's Children. North and South would have reflected my life in Britain, spent in both the North and South of England, and my later years, divided between the Northern and Southern Hemispheres of the globe, as well as in countries commonly referred to as the 'advanced' North and the 'underdeveloped' South. North and South has already been appropriated by Mrs Gaskell, something that did not deter one popular American writer from using the title for a book of his. My memories of World War Two and the years afterwards made War and Peace a possible candidate, but readers expectnig an epic tale of Tolstoyan proportions may have been disappointed. To my knowledge, no other book has the title "Whe' Yu' From?". I am grateful to the Jamaican man whose question lingered in my memory and provided the title of this memoir, written decades later. This book is a word picture. It is, in a sense, a self-portrait, and like all portraits, it captures something of the character, it attempts to tell the truth, but it is not the whole truth. This is because it is not my intention to write my entire life story; rather I wish to tell about some of the things in my experience of life that have seemed important or interesting to me. Unlike a painted portrait, the picture I have created is intended to suggest the passage of time. While, for most of us in Western society, time is linear and unidirectional, like the flight of an arrov or the trajectory of a bullet, memory rearranges things, calling up images of the past in no particular order, making connections that may link events in various patterns, circular, web-like, superimposed. The stream of consciousness is very unlike that of streams we encounter in the physical world. Connections are made in all directions; thoughts hop back and forth in time and space, from topic to topic. My book is a composition drawn from periods, events and thoughts as I remember them. Like life itself, it is made up of patches, some good, some bad, but in my experience, always fascinating. In recording my memories, I have been as accurate as possible. Little of what I have written is about spectacular sights and strange customs. Much of it focuses on my more modest explorations includng observations of everyday things that have attracted my attention. Reading through the chapters, I am struck by my childhood freedom to roam and engage in 'dangerous' activities like climbing trees and playing beside streams, things that many children today are no longer allowed to enjoy. Also noticeable is the survival of traditions and superstitions from the distant past. Obvious too, is my preoccupation with place names, both official ones that appear on maps and sign boards and those used by locals and children, names rarely seen in print. If there is any uniting theme to be found in what I have written, it must be my education in the fields, woods and streets of my English homeland, in the various other countries in which I have lived and travelled, as well as more formally from books and in classrooms. Much of my book is concerned with people and places. Many of the people I mention are among those who have been, and often have remained, important and close to me. Others I remember from only the briefest of encounters, but they remain in my memory because of some specific incident or circumstance that fixed a lasting image in my mind. Some of my closest friends and relatives, however, appear nowhere in these pages or they receive only the slightest mention. This is not because they played an unimportant roles in my life. It is because this book is not the whole story. Among those whe receive little or no mention are some who are especially close to me, with whom I have shared happy and sad times and who have shown me and my family much kindness, giving support when this was needed. Some I have known since childhood and have popped up at various times in my life, often in different parts of the world. Although years may pass without me seeing them, in an important sense they are always with me. These people know who they are. I hope that they know how much I love and appreciate them. When writing my memoir, I consulted a few of the people mentioned in this book, but in the main, I have relied on my own memory, asided by daiary and notebook entries and old correspondence. In the preparation of this manuscript, I benefited greatly from the expert advice and encouragement of Neil Marr of BeWrite Books. My wife Anne, inspiration for this book, also contributed in the valuable role of critic. She has my undying gratitude.

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This paper presents an approach to derive requirements for an avionics architecture that provides onboard sense-and-avoid and autonomous emergency forced landing capabilities to a UAS. The approach is based on two design paradigms that (1) derive requirements analyzing the common functionality between these two functions to then derive requirements for sensors, computing capability, interfaces, etc. (2) consider the risk and safety mitigation associated with these functions to derive certification requirements for the system design. We propose to use the Aircraft Certification Matrix (ACM) approach to tailor the system Development Assurance Levels (DAL) and architecture requirements in accordance with acceptable risk criteria. This architecture is developed under the name “Flight Guardian”. Flight Guardian is an avionics architecture that integrates common sensory elements that are essential components of any UAS that is required to be dependable. The Flight Guardian concept is also applicable to conventionally piloted aircraft, where it will serve to reduce cockpit workload.

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Real estate markets in Chinese cities are in transition. Advertising for new developments in these markets often reflects changing city aspirations and branding rather than environmental and social experience. This paper investigates real estate marketing as a site of potential ethical transformation of values related to new urban development. It uses Kenneth Burke’s rhetorical analysis as an approach to coding real estate representations from in-flight magazine advertisements as a means of capturing environmental and social viewpoints in China during 2008 - 2009. Both Chinese and foreign participants coded representations into four code modalities. These were based on anthropocentric - non-anthropocentric environmental orientations and nationalistic - universal social orientations. The results suggested that new developments in China are more likely to be understood as based on environmental resource use for continued national economic expansion rather than for a more sustainable world. Emerging patterns in coded representations have opened up the possibility of greater social choices that were however difficult to unambiguously decode from Chinese real estate advertising. From this it is concluded that it may take some time before real estate demand shifts in response to representations of Chinese eco-cities being promoted by Chinese policy makers in the 2000s.

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In the context of ambiguity resolution (AR) of Global Navigation Satellite Systems (GNSS), decorrelation among entries of an ambiguity vector, integer ambiguity search and ambiguity validations are three standard procedures for solving integer least-squares problems. This paper contributes to AR issues from three aspects. Firstly, the orthogonality defect is introduced as a new measure of the performance of ambiguity decorrelation methods, and compared with the decorrelation number and with the condition number which are currently used as the judging criterion to measure the correlation of ambiguity variance-covariance matrix. Numerically, the orthogonality defect demonstrates slightly better performance as a measure of the correlation between decorrelation impact and computational efficiency than the condition number measure. Secondly, the paper examines the relationship of the decorrelation number, the condition number, the orthogonality defect and the size of the ambiguity search space with the ambiguity search candidates and search nodes. The size of the ambiguity search space can be properly estimated if the ambiguity matrix is decorrelated well, which is shown to be a significant parameter in the ambiguity search progress. Thirdly, a new ambiguity resolution scheme is proposed to improve ambiguity search efficiency through the control of the size of the ambiguity search space. The new AR scheme combines the LAMBDA search and validation procedures together, which results in a much smaller size of the search space and higher computational efficiency while retaining the same AR validation outcomes. In fact, the new scheme can deal with the case there are only one candidate, while the existing search methods require at least two candidates. If there are more than one candidate, the new scheme turns to the usual ratio-test procedure. Experimental results indicate that this combined method can indeed improve ambiguity search efficiency for both the single constellation and dual constellations respectively, showing the potential for processing high dimension integer parameters in multi-GNSS environment.

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In the era of global knowledge economy, urban regions—seeking to increase their competitive edge, become destinations for talent and investment, and provide prosperity and quality of life to their inhabitants—have little chance achieving their development goals without forming effective knowledge-based urban development strategies. This paper aims to shed light on the planning and development processes of the knowledge-based urban development phenomenon with respect to the construction of knowledge community precincts aimed at making space for knowledge generation and place for knowledge communities. Following to a thorough review of the literature on knowledge-based urban development and strategic asset-based planning, the paper undertakes policy and best practice analyses to learn from the planning and development processes of internationally renowned knowledge community precincts—from Copenhagen, Eindhoven and Singapore. In the light of the analyses findings, this paper scrutinises major Australian knowledge community precinct initiatives—from Sydney, Melbourne and Brisbane—to better understand the dynamics of national practices, and benchmark them against the international best practice cases. The paper concludes with a discussion on the study findings and recommendations for successfully establishing space and place for both knowledge economy and society in Australian cities.

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Conference curatorial outline The focus of this symposium was to question whether interior design is changing relative to local conditions, and the effect globalization has on the performance of regional, particularly Southern hemisphere identities. The intention being to understand how theory and practice is transposed to ‘distant lands’, and how ideas shift from one place to another. To this extent the symposium invited papers on the export, translation and adoption of theories and practices of interior design to differing climates, cultures, and landscapes. This process, sometimes referred to as a shift from ‘the centre to the margins’, seeks new perspectives on the adoption of European and US design ideas abroad, as well as their return to their place of origin. Papers were invited from a range of perspectives including the export of ideas/attitudes to interior spaces, history of interior spaces abroad, and the adoption of ideas/processes to new conditions. Paralleling this trafficking of ideas are broader observations about interior space that emerge through specificity of place. These include new and emerging directions and differences in our understanding of interiority; both real and virtual, and an ever-changing relationship to city, suburb and country. Keeping within the Symposium theme the intention was to examine other places, particularly on the margins of the discipline’s domain. Semantic slippage aside, there are a range of approaches that engage outside events and practices enabling a transdisciplinary practice that draws from other philosophical and theoretical frameworks. Moreover as the field expands and new territories are opened up, the virtual worlds of computer gaming, animations, and interactive environments, both rely on and produce new forms of expression. This raises questions about the extent such spaces adopt or translate existing theory and practice, that is the transposition from one area to another and their return to the discipline.

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Distributed space-time coding (DSTC) exploits the concept of cooperative diversity and space-time coding to offer a powerful bandwidth efficient solution with improved diversity. In this paper, we evaluate the performance of DSTC with slotted amplify-and-forward protocol (SAF). Relay nodes between the source and the destination nodes are grouped into two relay clusters based on their respective locations and these relay clusters cooperate to transmit the space-time coded signal to the destination node in different time frames. We further extend the proposed Slotted-DSTC to Slotted DSTC with redundant code (Slotted-DSTC-R) protocol where the relay nodes in both relay clusters forward the same space-time coded signal to the destination node to achieve a higher diversity order.

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Cost implications related to the physical resources such as land and building in organisation is significant. Management entity of government or private sectors has often ignored the importance and the contribution gained from the physical resources towards their organisation. This source is a precious asset that can generate income if properly managed. This paper aims to explore the current trends in space management internationally, both from the government and private sector perspectives. A case study is conducted to study the level of effectiveness of space management in one of the government institutions in Malaysia. The findings from the case study will be compared with the current international trend of space management. The study will enrich the current understanding of space management in government properties, as well as to compare the level of space management effectiveness of government properties in Malaysia with the international trends and proposed suggestions to improve current practices of space management of Malaysian government’s properties. Keywords:

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We consider the space fractional advection–dispersion equation, which is obtained from the classical advection–diffusion equation by replacing the spatial derivatives with a generalised derivative of fractional order. We derive a finite volume method that utilises fractionally-shifted Grünwald formulae for the discretisation of the fractional derivative, to numerically solve the equation on a finite domain with homogeneous Dirichlet boundary conditions. We prove that the method is stable and convergent when coupled with an implicit timestepping strategy. Results of numerical experiments are presented that support the theoretical analysis.

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Presentation Structure: - THEORY - CASE STUDY 1: Southbank Institute of Technology - CASE STUDY 2: QUT Science and Technology Precinct - MORE IDEAS - ACTIVITY

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This paper summarises the achievements of the Smart Skies Project, a three-year, multi-award winning international project that researched, developed and extensively flight tested four enabling aviation technologies: an electrooptical mid-air collision avoidance system, a static obstacle avoidance system, a mobile ground-based air traffic surveillance system, and a global automated airspace separation management system. The project included the development of manned and unmanned flight test aircraft, which were used to characterise the performance of the prototype systems for a range of realistic scenarios under a variety of environmental conditions. In addition to the collection of invaluable flight data, the project achieved world-firsts in the demonstration of future automated collision avoidance and separation management concepts. This paper summarises these outcomes, the overall objectives of the project, the research and the development of the prototype systems, the engineering of the flight test systems, and the results obtained from flight-testing.

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A review of 291 catalogued particles on the bases of particle size, shape, bulk chemistry, and texture is used to establish a reliable taxonomy. Extraterrestrial materials occur in three defined categories: spheres, aggregates and fragments. Approximately 76% of aggregates are of probable extraterrestrial origin, whereas spheres contain the smallest amount of extraterrestrial material (approx 43%). -B.M.

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The future emergence of many types of airborne vehicles and unpiloted aircraft in the national airspace means collision avoidance is of primary concern in an uncooperative airspace environment. The ability to replicate a pilot’s see and avoid capability using cameras coupled with vision based avoidance control is an important part of an overall collision avoidance strategy. But unfortunately without range collision avoidance has no direct way to guarantee a level of safety. Collision scenario flight tests with two aircraft and a monocular camera threat detection and tracking system were used to study the accuracy of image-derived angle measurements. The effect of image-derived angle errors on reactive vision-based avoidance performance was then studied by simulation. The results show that whilst large angle measurement errors can significantly affect minimum ranging characteristics across a variety of initial conditions and closing speeds, the minimum range is always bounded and a collision never occurs.