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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Light and Matter

Castine, Timothy Creighton 05 June 2000 (has links)
The images which comprise the majority of these pages have been given the name Light Sculptures. They are not computer generated or hand drawn, they are photographs of the interaction between light and a reflective cylinder. Originally color transparencies, the Sculptures have been interpreted by the computer as inverted, greyscale images. What was once a black background is now white paper, and what were once lines of light are now lines of ink. The sculptures were synthesized through experimentation with the fundamental elements of architecture: Light, Material, and Geometry. Following the series of Light Sculptures are images of Objects through which materials, tectonics, and proportion were explored. The design and fabrication of each piece was guided by the intent to make something which functioned structurally, visually, and tactily as an integrated whole. / Master of Architecture
302

A study of Path and Light

Samal, Dhruva 19 December 2005 (has links)
Light rays emanating from the sun, interact with objects which we see in our everyday life and give them presence. Without light these objects would not be visible to us. The interaction of Light with objects of different qualities within a space creates a variety of environments. People direct their attention to elements of the visual environment which provide information needed to carry out conscious and unconscious activities. These activities include movement along a path, introspection in the form of meditation, fascination. In conclusion, this is a process which involves more than just what is visible to the eye in terms of luminance levels but the overall sensory experience. Personal experience is the vehicle for interpretation for both designers and inhabitants. / Master of Architecture
303

Half-Lit: Georgetown University Center for the Study of Light

Sutjipto, Michael 12 June 2012 (has links)
It is the intention of this thesis to explore the idea of half light, as put forward by Luis Barragan: "Architects are forgetting the need of human beings for half-light, the sort of light that imposes a tranquility, in their living rooms as well as in their bedrooms."¹ The exploration will occur through photography, writing, and architectural design. But most of all, the emphasis will be on developing a rich internal vocabular and set of intuitions, and then see what architecture emerges from these intuitions. / Master of Architecture
304

The right light at the right time for bipolar patients. An exploratory study of light environments for patients with bipolar disease in behavioral health clinics

Svanberg, Mira January 2021 (has links)
Research has showed that different light scenarios have a profound effect on hospitalized bipolar patients. Different light situations decrease the hospital stay for patients during both manic and depressive episodes. Nevertheless, a field study carried out during this thesis work of two arbitrary patient rooms in Swedish behavioral health clinics showed no incorporation of this knowledge in the light design of the rooms. Both patient rooms had insufficient light levels both in terms of circadian recommendations and perceived brightness. Hence this thesis suggests an improved light design for patient rooms housing bipolar patients. The basis of the improved design is to incorporate a dynamic, circadian lighting that varies depending on the patient's need and diagnosed episode.
305

Atmospheres of Light

Hawes, Serene S. 23 May 2023 (has links)
No description available.
306

Second light-scattering and Kerr-effect virial coefficients of molecules with linear and lower symmetry.

Couling, Vincent William. 01 October 2014 (has links)
Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1995.
307

Built-light : analysis and generation of associative natural light environments.

Plummer, Henry Sheppard January 1975 (has links)
Thesis. 1975. M.Arch.--Massachusetts Institute of Technology. Dept. of Architecture. / Includes bibliographical references. / M.Arch.
308

Blue and Red Light Effects on Stomatal Oscillations

Ballard, Trevor R. 01 December 2018 (has links)
Plants absorb CO2 through pores in their leaves called stomata, which are known to open and close in response to myriad environmental and physiological triggers. We demonstrate that blue light inhibits stomatal aperture oscillations in both the guard cells and surrounding tissue layers, whereas these oscillations continue under the influence of red light. This observation of blue light behavior agrees with recent research and suggests another physiological pathway for oscillations.
309

Light Scattering Study on Single Wall Carbon Nanotube (SWNT) Dispersions

Wang, Tong 12 April 2004 (has links)
Carbon nanotubes, and particularly single wall carbon nanotubes (SWNTs) have attracted much attention for their unique structure, as well as for their excellent mechanical, electrical and thermal properties. Most properties of carbon nanotubs are closely related with its anisotropic structure and geometry factor. Characterization of carbon nanotube length is critical for understanding their behavior in solutions as well as in polymer composites. Microscopy, particularly atomic force microscopy, has been used for their length measurement. Microscopy, though straightforward, is quite laborious, particularly for statistically meaningful sampling. Light scattering can be used to measure particle dimensions. In this study, light scattering has been used to study polyvinyl pyrrolidone (PVP) wrapped SWNTs surfactant assisted aqueous dispersion and SWNT dispersion in oleum. To determine the length of SWNTs, Stokes - Mueller formalism was used, which is a universal model for particles with any size and shape. The Mueller matrix for an ensemble of long, thin cylinders proposed by McClain et al. was used in this study. This Mueller matrix includes the information of size (length and radius) and optical constants (refractive index and extinction coefficient) of cylinders. In this matrix, extinction coefficient, radius and length of SWNTs are unknown. By normalizing scattering intensity I(theta) (theta from 30 to 155 degree) to that at 30degree , the effects of radius and extinction coefficient were cancelled out. Thus, the effect of SWNT length on scattering intensity could be studied independently. A series of curves of normalized scattering intensity of SWNTs (I(theta) /I(30degree)) with varied length as a function of wave vector were predicted. A curve of normalized scattering intensity of SWNT as a function of wave vector was also obtained experimentally. By comparing experimental and predicted curves, average SWNT length in the dispersion has been determined. Scattering intensity at a given angle initially increases with concentration, and then reaches a critical concentration(C*), above which the scattering intensity decreases. This phenomenon has been attributed to the competition between scattering and absorption of light by the presence of SWNT. By using Beer-Lambert law, this phenomenon has been used to determine the molar absorption coefficient of SWNTs.
310

Luminance Characteristics of 1,3,5-Tris(1-pyrenyl)benzene and the Application on Organic Light-emitting Devices

Cheng, Chun-tai 12 August 2010 (has links)
We have developed high-efficiency blue organic light-emitting devices incorporate 1,3,5-Tri(1-pyrenyl)benzene(TPB3) as emitting layer and 4,7-diphenyl-1,10-phenanthroline(BPhen) as the electron transporting layer, which has a large Highest Occupied Molecular Orbital energy level and has good electron mobility. A device having the configuration : ITO(140 nm)/NPB(65 nm)/(TPB3 40nm)/BPhen(30 nm)/LiF(0.8 nm)/Al(200 nm) exhibited a maximum luminance at 9.5V of 29940 cd/m2, The maximum current and power efficiencies were 3.85 cd/A and 2.38 lm/W, respectively. The current and power efficiencies were greater than 3cd/A and 1.1 lm/W respectively, Over a large range of potentials (3.5~10.0V) with good Commission Internationale de l¡¦Eclairage (CIE) coordinates of (0.17, 0.22). These results indicate that TPB3 is good blue-emitting material for OLED applications. The photophysical and chemical properties of TPB3 have also been studied in this research.

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