Design Optimization of a High Power LED Matrix Luminaire

This work presents a methodology for optimizing the layout and geometry of an m x n high power (HP) light emitting diode (LED) luminaire. Two simulators are used to analyze an LED luminaire model. The first simulator uses the finite element method (FEM) to analyze the thermal dissipation, and the second simulator uses the ray tracing method for lighting analysis. The thermal and lighting analysis of the luminaire model is validated with an error of less than 10%. The goal of the optimization process is to find a solution that satisfies both thermal dissipation and light efficiency. The optimization goal is to keep the LED temperature at an acceptable level while still obtaining uniform illumination on a target plane. Even though no optical accessories or active cooling systems are used in the model, the results demonstrate that it is possible to obtain satisfactory results even with a limited number of parameters. The optimization results show that it is possible to design luminaires with 4, 6 and up to 8 HP-LEDs, keeping the LED temperature at about 100 degrees C. However, the best uniformity on a target plane was found by the heuristic algorithm

Design Optimization of a High Power LED Matrix Luminaire

This work presents a methodology for optimizing the layout and geometry of an m x n high power (HP) light emitting diode (LED) luminaire. Two simulators are used to analyze an LED luminaire model. The first simulator uses the finite element method (FEM) to analyze the thermal dissipation, and the second simulator uses the ray tracing method for lighting analysis. The thermal and lighting analysis of the luminaire model is validated with an error of less than 10%. The goal of the optimization process is to find a solution that satisfies both thermal dissipation and light efficiency. The optimization goal is to keep the LED temperature at an acceptable level while still obtaining uniform illumination on a target plane. Even though no optical accessories or active cooling systems are used in the model, the results demonstrate that it is possible to obtain satisfactory results even with a limited number of parameters. The optimization results show that it is possible to design luminaires with 4, 6 and up to 8 HP-LEDs, keeping the LED temperature at about 100 degrees C. However, the best uniformity on a target plane was found by the heuristic algorithm

Butterfly gyroid nanostructures as a time-frozen glimpse of intracellular membrane development

The formation of the biophotonic gyroid material in butterflywing scales is an exceptional feat of evolutionary engineering of functional nanostructures. It is hypothesized that this nanostructure forms by chitin polymerization inside a convolutedmembrane of corresponding shape in the endoplasmic reticulum. However, this dynamic formation process, including whether membrane folding and chitin expression are simultaneous or sequential processes, cannot yet be elucidated by in vivo imaging. We report an unusual hierarchical ultrastructure in the butterfly Thecla opisena that, as a solid material, allows high-resolution three-dimensional microscopy. Rather than the conventional polycrystalline spacefilling arrangement, a gyroid occurs in isolated facetted crystallites with a pronounced size gradient.When interpreted as a sequence of time-frozen snapshots of the morphogenesis, this arrangement provides insight into the formation mechanisms of the nanoporous gyroid material as well as of the intracellular organelle membrane that acts as the template

Study on Micromoulding of A High Viewing Angle LED Lens

Lenses are used to mount on the light-emitting diode (LED) chip to obtain the desired light distribution patterns. In this study, a lens for large viewing angle and high uniformity LED has been developed with optical grade poly methyl methacrylate (PMMA) material. TracePro software was used to design the lens while Moldex 3D software was implemented to design the mould and the mould filling phenomena. Together with micromoulding technology and Taguchi experimental method with control parameters were mould temperature (MoT), melt temperature (MT), and injection speed, a lens with optical uniformity of 87.18% and viewing angle of 128° has been developed. The experimental results showed that MoT and MT were the main factors affecting the optical quality, each with contributions greater than 50 and 30%, respectively. Though this lens is relatively small in dimension, a draft angle is needed for successful removal of the moulded PMMA lens from the mould

An Overview of the Performance of the Chandra X-Ray Observatory

The Chandra X-ray Observatory is the X-ray component of NASA's Great Observatory Program which includes the recently launched Spitzer Infrared Telescope, the Hubble Space Telescope (HST) for observations in the visible, and the Compton Gamma-Ray Observatory (CGRO) which, after providing years of useful data has reentered the atmosphere. All these facilities provide, or provided, scientific data to the international astronomical community in response to peer-reviewed proposals for their use. The Chandra X-ray Observatory was the result of the efforts of many academic, commercial, and government organizations primarily in the United States but also in Europe. NASA's Marshall Space Flight Center (MSFC) manages the Project and provides Project Science; Northrop Grumman Space Technology (NGST -- formerly TRW) served as prime contractor responsible for providing the spacecraft, the telescope, and assembling and testing the Observatory; and the Smithsonian Astrophysical Observatory (SAO) provides technical support and is responsible for ground operations including the Chandra X-ray Center (CXC). Telescope and instrument teams at SAO, the Massachusetts Institute of Technology (MIT), the Pennsylvania State University (PSU), the Space Research Institute of the Netherlands (SRON), the Max-Planck Institut fur extraterrestrische Physik (MPE), and the University of Kiel also provide technical support to the Chandra Project. We present here a detailed description of the hardware, its on-orbit performance, and a brief overview of some of the remarkable discoveries that illustrate that performance.Comment: 71 pages, 66 Figures, accepted for Experimental Astronom

2012 GREAT Day Program

SUNY Geneseo’s Sixth Annual GREAT Day.https://knightscholar.geneseo.edu/program-2007/1006/thumbnail.jp

A multi-dimensional energy-based analysis of neighbourhood sustainability assessment tools: are institutional indicators really missing?

Neighbourhood Sustainability Assessment Tools (NSATs) have become the modern day template for urban planners to achieve sustainable development in their communities, districts and cities. The popularity of the pioneering NSATs led to the creation of other tools in different regions. Also, with the popularity and replication of these tools came the replication of their limitations. The most notable limitation and motivation for this study is the inadequate recognition of the complexities of institutional dimensions (i.e. policies, laws and regulation) that contribute to mainstreaming and operationalising sustainable neighbourhood development. Studies that have investigated NSATs generally argue lack of coverage of the institutional dimension. However, there has been little consistent and explicit mention of the precise indicators and criteria sought out to make this claim. Also, there is a clear confusion as to what institutional indicators actually are, what characteristics they possess and how best they can be identified. This study, via the lens of energy-based indicators, expands on the role of the institutional indicator and its associated dimensions. This study also utilises a multi-dimensional approach to indicator analysis and draws out current trend or characteristics of institutional indicators in 15 currently existing NSATs. The results show a limited view on the classification of institutional indicators. The study also demonstrates that there are more institutional indicators than previously reported in prior studies. Additionally, this study confirms that an institutional indicator cannot be a single entity or identity but rather it must operate under the linkage of the other dimensions (environment, social and economic). Finally, this study, based on the analysis of 15 NSATs provides a definition of what can be considered an institutional indicator. In conclusion, it is recommended that future development of NSATs should ensure a constant institutional link to indicators, as this could provide an enhanced alternative to the development of NSATs, particularly for regions that are looking into developing their own assessment tools

Discrete Automation - Eyes of the City

Observing people’s presence in physical space and deciphering their behaviors have always been critical actions to designers, planners and anyone else who has an interest in exploring how cities work. It was 1961 when Jane Jacobs, in her seminal book “The Death and Life of Great American Cities”, coined a famous expression to convey this idea. According to Jacobs, “the natural proprietors” of a certain part of the metropolis – the people who live, work or spend a substantial amount of time there – become the “eyes on the street.” Their collective, distributed, decentralized gaze becomes the prerequisite to establishing “a marvelous order for maintaining the safety of the streets and the freedom of the city.” Almost half a century later, we find ourselves at the inception of a new chapter in the relationship between the city and digital technologies, which calls for a reexamination of the old “eyes on the street” idea. In the next few years, thanks to the most recent advances in Artificial Intelligence, deep learning and imaging, we are about to reach an unprecedented scenario, the most radical development in the evolution of the Internet-of-Things: architectural space is acquiring the full ability to “see.” Imagine that any room, street or shop in our city can recognize you, and autonomously respond to your presence. With Jacobs’s “eyes on the street,” it was people who looked at other people or the city and interpreted its mechanisms. In this new scenario, buildings and streets similarly acquire the ability to observe and react as urban life unfolds in front of them. After the “eyes on the street,” we are now entering the era of the “Eyes of the City.” What happens, then, to people and the urban landscape when the sensor-imbued city is able to gaze back? What we are currently facing is an “utopia or oblivion” crossroads, to say it with the words of one of the most notable thinkers of the past century, Richard Buckminster Fuller. We believe that one of the fundamental duties of architects and designers today is to grapple with this momentous shift, and engage people in the process. “Eyes of the City” aims to experiment with these emerging scenarios to better comprehend them, deconstructing the potential uses of new technologies in order to make them accessible to everyone and inspire people to form an opinion. Using critical design as a tool, the exhibition seeks to create experiences that will encourage people to get involved in defining the ways in which new technologies will shape their cities in years to come. For this reason, it recognizes in Shenzhen’s Futian high-speed railway station its natural home – a place where to reach a broad, diverse audience of intentional visitors and accidental passersby, and a space where, just like in most other liminal transportation hubs, the impact of an “Eyes of the City” scenario is likely going to be felt the most