• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 957
  • 219
  • 123
  • 83
  • 25
  • 22
  • 15
  • 12
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • Tagged with
  • 2018
  • 326
  • 270
  • 206
  • 204
  • 191
  • 181
  • 158
  • 158
  • 128
  • 126
  • 120
  • 108
  • 104
  • 102
  • 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.

Node activation policies for energy-efficient coverage in rechargeable sensor systems

Jaggi, Neeraj. January 1900 (has links)
Thesis (Ph.D.)--Rensselaer Polytechnic Institute, 2007. / Adviser: Koushik Kar. Includes bibliographical references.

Analysis and application of capacitive displacment sensors to curved surfaces

Smith, Philip T. January 2003 (has links) (PDF)
Thesis (M.S.)--University of Kentucky, 2003. / Title from document title page (viewed Sept. 10, 2004). Document formatted into pages; contains x, 146 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 143-144).

On the evaluation of edge detectors and related evaluation techniques

Christiansen, Peter Ludwig 29 January 2014 (has links)
M.Ing. (Mechanical Engineering) / This dissertation concerns itself with the evaluation of edge detectors. Existing evaluation methods are described and discussed. Various edge detectors are described and used to obtain experimental results. A new evaluation method which takes into consideration both a subjective and .non-subjective component is proposed. This new method is not meant to be definitive. The reason for this is that the author feels that this dissertation should primarily highlight the factors that are important in evaluating edge detectors. It was found that if it is not possible to set parameters for more sophisticated edge detectors, they do not always produce better results than the simpler methods such as the Sobel operator.

Characterization and analysis of a multicolor quantum well infrared photodetector

Hanson, Nathan A. 06 1900 (has links)
This thesis presents analysis and characterization of performance of a newly designed, multicolor quantum well infrared photodetector (QWIP). Specifically, it focuses on a detector capable of detecting infrared emissions in the near infrared (NIR), mid-wavelength infrared (MWIR), and long-wavelength infrared (LWIR). Through photocurrent spectroscopy and performance analysis, this prototype detector can be classified and prepared for possible future use within the U.S. Armed Forces. Certain military applications require a highly accurate, reliable, sensitive, and multispectral infrared detector to identify targets and ensure mission success. By designing and fabricating a multicolor quantum well infrared photodetector, simultaneous detection of targets in the near infrared, mid-wavelength infrared and long-wavelength infrared is possible using only one detector. In addition, power and cooling requirements for quantum well infrared detectors makes them suitable for use in the field. / US Navy (USN) author.

Chemical surface modifications for improved mid-infrared evanescent field sensing systems

Janotta, Markus 05 1900 (has links)
No description available.

Modeling and data analysis of conductive polymer composite sensors /

Lei, Hua, January 2006 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University. Dept. of Chemical Engineering, 2006. / Includes bibliographical references (p. 129-135).

Wireless sensor interrogator design for passive, resonant frequency sensors using frequency modulation spectroscopy

Peterson, Brian James. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Todd Kaiser. Includes bibliographical references (leaves 74-76).

The development of a high count rate neutron flux monitoring channel using silicon carbide semiconductor radiation detectors

Reisi Fard, Mehdi, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 254-257).

Charge carrier manipulation for high performing near-infrared light detection

Li, Ning 23 August 2018 (has links)
Near infrared (NIR) light detection has drawn substantial attentions in a variety of applications. NIR detectors prepared by the solution processable organic semiconductors and organic-inorganic hybrid material systems have the advantages for achieving flexible, light weight and large area NIR detection devices. The aim of this research work is to study the modulation of the photo-generated charge carriers in perovskite and polymer systems for attaining high performing solution-processable NIR phototransistors (PTs) and photodiodes (PDs). In the first part, an organo-lead halide perovskite/polymer bi-layer channel PT is discussed. Compared to the performance of the polymer only PTs, the PTs with a perovskite/polymer hybrid channel exhibit a profound broadband enhancement in photoresponsivity over the light wavelength range from UV to NIR. The improved performance in the hybrid perovskite/polymer PTs is closely associated with the efficient charge separation and transfer between the perovskite and polymer functional layers in the heterojunction. With the success in developing the bi-layer perovskite/polymer PTs, the enhancement in NIR detection is further realized in PTs by incorporating a bulk heterojunction (BHJ) channel. The BHJ channel is formed by blending NIR sensitive polymer donor with three different acceptor materials for enhancing exciton dissociation and charge separation efficiency. It is shown that the use of donor/acceptor BHJ greatly facilitates the dissociation of photo generated excitons. The efficient exciton dissociation helps to boost the utilization of the photo generated excitons, and thereby improves the photoresponsivity. Although the PTs with a BHJ channel possess high photoresponsivity, the photosensitivity of these NIR PTs is still less than satisfactory. The results reveal that a higher activation energy of charge carriers is favorable for a lower carrier density in the channel. While under NIR light illumination, the mobile charge carriers, created due to the dissociation of the photo generated excitons, result in a dramatic increase in carrier density in the active channel. The increase in carrier density under NIR illumination, gives rise to a higher channel current, thereby a higher photosensitivity. A pixel-less NIR imaging device based on light up-conversion from near-infrared to green is demonstrated. A polymer donor/non-fullerene acceptor BHJ serving as the NIR sensitive unit is integrated monolithically with a perovskite-based light emitting diode (LED) unit for achieving light up-conversion from NIR to visible light. The BHJ serves as an NIR sensitive hole injection layer in the perovskite LEDs. Therefore, the efficient electroluminescence in area where NIR-induced efficient charge injection occurs in the LEDs can be displayed clearly, producing the visible light image. The photoresponsivity of perovskite based UV-Visible-NIR photodiodes (PDs) is discussed in the last part of the thesis. A periodic nano-grating hole transporting layer (HTL), formed by the nano-imprinting, is adopted for enhancing the photoresponsivity of the PDs. Theoretical simulation reveals that the periodic nano-grating HTL helps to improve light absorption in the active layer, caused by the enhanced light in-coupling effect. In the meantime, the nano-grating HTL based PDs exhibit weak angular dependency as compared to that of the planar control ones which is appealing for wide angle light detections.

On-line validation of a distributed sensor system /

Sakti, Setyawan Purnomo. Unknown Date (has links)
Thesis (MEng) -- University of South Australia, 1994

Page generated in 0.047 seconds