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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.
11

A Study of Establishing Search and Rescue Planning Information System

Yang, Hsien-Chang 08 February 2012 (has links)
For the sake of maintaining people¡¦s safety and property at sea, IMO adopted the International Convention on Maritime Search and Rescue in 1979 which regulates all Parties shall ensure that necessary arrangements are made for the provision of adequate search and rescue services for persons in distress at sea round their coasts. Furthermore, the 2nd paragraph of Article 98 of United Nations Convention on the Law of the Sea, 1982, says every coastal State shall promote the establishment, operation and maintenance of an adequate and effective search and rescue service regarding safety on and over the sea and, where circumstances so require, by way of mutual regional arrangements cooperate with neighbouring States for this purpose. Thus, for the humanitarian and live saving at sea as well as complying with the relevant international conventions, prosecution of search and rescue at sea is the privilege for the competent authority and relating originations of our government. Accurate computation of drifting and well-planned search and rescue activity cope with prompt search and rescue prosecution are the key elements for successful rescue at sea. Nowadays, Taiwan government faces some problems. One is no search and rescue information system as US, UK and Canada installed to calculate the drifting of people or ships in distress promptly. Second is lack of thorough ocean data. Even though the SAR information system which was purchasing from other country has been installed, the accuracy will be reduced due to the uncompleted surrounding ocean wind and current data. Therefore, the author study the Search and Rescue Optimal Planning System (SAROPS) of US coast guard in order to provide suggestions for the relevant rescue units in Taiwan when establishing the similar system to promote the Search and Rescue efficiency and adopt scientific planning methodology
12

A 6-bit 4.8mW SAR pipelined ADC using improved TIQ technology

Lee, Yan-huei 12 July 2005 (has links)
A improved less area 6-bit 3.3V SAR pipelined ADC is proposed. In this work, a 3-bit ADC is designed by the improved TIQ technology and flash like SAR ADC selection scheme. With the proposed TIQ method, it cancels the reference voltage generators and the backend encoders to reduce the area cost, besides the flash-like SAR ADC selection scheme makes the ADC still operate at high speed. The new 3-bit DAC in the MDAC is completed only by MOS transistors which channel widths and lengths are only adjusted to form each DAC output-voltage levels rather than using of resisters and capacitors in voltage mode. By the method, the area of the new DAC is reduced. By combining the proposed 3-bit ADC with the proposed 3-bit MDAC, an improved 6-bit ADC with less area is designed. By the TSMC 2P4M 0.35µm CMOS process, the area of the ADC is less than 0.017mm . The work shows that the power consuming is 3.77mW, the sampling rate is 160MS/S, the DNL is 0.344, and the INL is 0.74.
13

SAR Distribution and Temperature Increase in the Human Head for Mobile Communication

Guo, Zhi-Ming 26 July 2002 (has links)
Rapid development of wireless communications has led to the excessive use of wireless equipments. The purpose of communication is achieved through the transmission and reception of electromagnetic waves by the wireless equipments. Living in the environment of massive electromagnetic exposure coming from these wireless equipments, the health issue is a growing concern among the people who use the equipments and also the general public. The GSM communication system is the most widely used segment of wireless communications currently in Taiwan. The user of the mobile terminal (handset) is in close proximity to the radiating antenna. Most of the EM radiation emitting from the antenna will pass through the body of the user and be absorbed by the human tissue. It is therefore important to consider possible health hazards due to this type of EM exposure. Among all the possible biological effects caused by EM exposure, the heating effect is the most significant and its influence on biological tissues is proven. Currently most countries require the handsets to be tested for SAR values before the handsets are ready for purchasing on the markets. SAR tests require the utilization of expensive measurement facilities. Moreover, even though the phantom used for SAR measurement is prepared according to standards, theoretically the phantom is still not identical to the anatomical constituents of the human head. Henceforth, it is necessary to investigate the field distribution inside the human head, using an anatomical model, due to the exposure of radiation coming from the handset antennas from the theoretical point of view. The whole human body is an inhomogeneous lossy dielectrics as far as EM wave propagation is concerned. This feature renders the problem easy to tackle using the FDTD numerical method. This thesis presents a method to build up a numerical human head model suitable for the FDTD analysis using data set from the ¡§visible human¡¨ project readily available from the internet. The thesis then investigates the field distribution inside the human head, under the exposure of the quarter-wavelength monopole antenna on a dielectric covered metal box. Temperature increases due to the absorption of EM energy by the human head will then be deducted from the bioheat equation.
14

A study of SAR ADC and implementation of 10-bit asynchronous design

Kardonik, Olga 13 December 2013 (has links)
Successive Approximation Register (SAR) Analog-to-Digital Converters (ADCs) achieve low power consumption due to its simple architecture based on dominant digital content. SAR ADCs do not require an op-amp, so they are advantageous in CMOS technology scaling. The architecture is often the best choice for battery-powered or mobile applications which need medium resolution (8-12 bits), medium speed (10 - 100 MS/s) and require low-power consumption and small form factor. This work studies the architecture in depth, highlighting its main constraints and tradeoffs involving into SAR ADC design. The work researches asynchronous operation of SAR logic and investigates the latest trends for ADC’s analog components – comparator and DAC. 10-bit asynchronous SAR ADC is implemented in CMOS 0.18 µm. Design’s noise and power are presented as a breakdown among components. / text
15

MODELING BIOPHYSICAL VARIABLES IN THE CANADIAN HIGH ARCTIC USING SYNTHETIC APERTURE RADAR DATA

Collingwood, Adam 04 February 2014 (has links)
The estimation or modeling of biophysical variables such as surface roughness, vegetation phytomass, and soil moisture in the Arctic is an important step towards understanding arctic energy fluxes, effects of changing climate, and hydrological patterns. This research uses Synthetic Aperture Radar (SAR) data, along with ancillary optical and environmental data, to create models that estimate these biophysical variables across different High Arctic landscapes, with the goal of applying the models across even larger areas. Field work was conducted at two High Arctic locations on Melville Island, Nunavut, Canada. At each location, surface roughness values were measured at a number of randomized plot locations using a pin meter. Soil moisture values were measured using a time domain reflectometry (TDR) instrument within six hours of multiple overpasses of the RADARSAT-2 SAR sensor. Surface roughness models were generated with multi-incidence angle and fully polarimetric SAR data, with resulting R2 values ranging between 0.39 and 0.66, and normalized root mean squared error (N_RMSE) values of 14% - 22%. The output from the final surface roughness model was used as an input to the soil moisture models. Vegetation phytomass was modeled with multi-angular SAR data, using a soil adjusted vegetation index (SAVI) derived from optical data across the study area as a measure of verification. The resulting model had a significant (p <0.05) relationship to the SAVI values, with an R2 of 0.60. This model was then compared to field-collected above-ground phytomass values, and a model was derived that related SAR data directly to phytomass. This model again showed a strong relationship, with an R2 value of 0.87. The final biophysical variable that was modeled, soil moisture, showed moderate agreement to field-measured soil moisture values (R2 = 0.46, N_RMSE = 0.15%), but much stronger relationships were found for relative moisture values at fine scales across the landscape. These models, when taken together, demonstrate that SAR data is capable of modeling biophysical variables across high latitude environments. These models will help address larger questions, such as how SAR can be used to better understand moisture and energy exchanges over regional areas in high arctic environments. / Thesis (Ph.D, Geography) -- Queen's University, 2014-02-03 16:52:26.856
16

POSTHARVEST DISEASE CONTROL OF MELONS USING SYSTEMIC ACQUIRED RESISTANCE AND OTHER

Bokshi, A I January 2008 (has links)
Doctor of Philosophy (PhD) / The goal of this research was to test commercially viable alternative methods to fungicides for controlling storage diseases of melons that are safe for human health and the environment. Initially, experiments were conducted on melons to develop a protocol for optimum conditions of disease development during storage for different pathogens and for different stages of fruit maturity. For all pathogens tested, the study found that humidity greater than 90% and temperatures above 20° C support infection and rapid growth of disease. Differences in the rate of infection and extent of disease development after the inoculation of different storage pathogens was observed between rockmelon and honeydew melons, indicating differences in host pathogen interactions. Among the tested pathogens, Alternaria spp. was the least aggressive in infection and disease severity, growing considerably slower than Fusarium acuminatum which was moderately aggressive and Rhizopus spp. which was very aggressive, in comparison. Green half-slip melons showed greater resistance to pathogen attack than green full-slip fruit, while yellow full-slip melons were highly susceptible to pathogen attack. Therefore, the laboratory experiments for postharvest treatments of rockmelons were performed using green full-slip fruit challenged with F. acuminatum. Evaluation of physical and safe chemical methods of postharvest treatment to control postharvest diseases of melons showed that none of the treatments alone was as effective as the commercially available fungicide. Hot water solutions of safe compounds considerably increase their efficacy against postharvest rots, however, symptoms of phytotoxicity on the rind after dipping made their use unacceptable. Iodine was the only safe chemical tested which did not cause any phytotoxicity on melons. When combined with hot water, iodine showed the best control of storage rots and was as good as the fungicides carbendazim or guazatine. Hot water iodine dipping of fruit also delayed ripening and fruit were firmer during storage for a longer period of time. Systemic acquired resistance (SAR) was evaluated as a method of controlling powdery mildew in glasshouse grown rockmelon seedlings by treating with the activators 2,6-dichloroisonicotinic acid (INA) or benzothiadiazole (BTH) or water. Increased resistance due to application of INA or BTH, was observed by the reduction of powdery mildew on pre-inoculated detached leaves and also on intact leaves from natural infections. Heightened resistance due to spraying with elicitors of SAR, was further evident by the increased activities of the pathogenesis related proteins (PR proteins), peroxidase and accumulation of phenolics or antifungal compounds during and after challenge inoculation. Field grown rockmelons were treated with INA or BTH or BABA (β-aminobutyric acid) or water at various stages of plant growth and evaluated for increased resistance against pre and postharvest diseases. Both powdery mildew and downy mildew were significantly less on the SAR elicitor treated plants. Preharvest treatment with SAR elicitors also reduced storage diseases of the harvested rockmelon fruit. The reduction in postharvest disease was similar whether plants were treated once, three weeks before harvest, or given four sprays during the growing season beginning at anthesis. A further postharvest dip with 500 ppm of guazatine gave substantial reduction of storage rots of melons. Enhanced activities of chitinase and peroxidase, two major PR-proteins, compared to the control, indicated induction of defence had occurred in the foliage and fruit as a result of SAR. Over the course of four field and one glasshouse experiments slight phytotoxicity was observed in plants frequently sprayed with INA or BTH, but no phytotoxicity was seen after a single spray during the late stages of fruit development. The combination of SAR elicitor treatment and use of a safe postharvest dip provided substantial control of storage rots of rockmelons. The best treatment for control of storage rots involved application of BTH (50 ppm) two weeks before harvest, combined with a hot iodine dip (55° C) of fruit, achieving equivalent or better disease control than use of guazatine fungicide dip.
17

The Analysis of Sea Ice Cover with the Use of Synthetic Aperture Radar (SAR) Imagery

Ouellet, Martin January 1996 (has links)
Note:
18

Vergleichende Analyse von SAR-Daten für die Regionalisierung des Wassergehalts im Oberboden

Prietzsch, Carmen Corinna January 1998 (has links)
Flugzeug- und Shuttle getragene SAR-Systeme werden zur Ableitung des Bodenwassergehalt im Oberboden verwendet. Die Untersuchungsgebiete lagen auf der Insel Rügen, in Oberbayern (Oberpfaffenhofen) und in Oklahoma (Little Washita). Die Regionalierung mit Fernerkundungsdaten wird anhand von geostatistisch aufbereiteten Referenzmessungen aus dem Feld verifiziert. Verschiedene Ableitungsverfahren (Regression, Rückstreuungsmodellierung, Nomogramme und Inversionsmodellierung) werden verglichen und Fehlermargen werden abgeleitet. / Airborne and shuttle-borne SAR systems are used for the retrieval of the soil water content in the upper soil layer. The investigation areas were located on Ruegen island, southern Bavaria, Germany, and Oklahoma (Little Washita), USA. The regionalization with remote sensing data is checked with geostatistically prepared field measurements of the soil water content. Different retrieval methods are compared (regression analysis, backscattering modeling, nomograms and inversion modelling) and error margins are retrieved.
19

A Study of Successive Approximation Registers and Implementation of an Ultra-Low Power 10-bit SAR ADC in 65nm CMOS Technology

Hedayati, Raheleh January 2011 (has links)
In recent years, there has been a growing need for Successive Approximation Register (SAR) Analog-to-Digital Converter in medical application such as pacemaker. The demand for long battery life-time in these applications poses the requirement for designing ultra-low power SAR ADCs. This thesis work initially investigates and compares different structures of SAR control logics including the conventional structures and the delay line based controller. Additionally, it focuses on selection of suitable dynamic comparator architecture.  Based on this analysis, dynamic two-stage comparator is selected due to its energy efficiency and capability of working in low supply voltages. Eventually, based on these studies an ultra-low power 10-bit SAR ADC in 65 nm technology is designed. Simulation results predict that the ADC consumes 12.4nW and achieves an energy efficiency of 14.7fJ/conversion at supply voltage of 1V and sampling frequency of 1kS/s. It has a signal-to-noise-and-distortion (SINAD) ratio of 60.29dB and effective-number-of-bits (ENOB) of 9.72 bits. The ADC is functional down to supply voltage of 0.5V with proper performance and minimal power consumption of 6.28nW.
20

Δημιουργία φορέων με βάση τον αφρώδη ιό και το στοιχείο SAR/MAR και ανάλυση της γονιδιακής έκφρασής των σε διαμολυσμένα κύτταρα

Γεωργίτση, Μαριάννα 04 January 2008 (has links)
Σκοπός της συγκεκριμένης μελέτης είναι η δημιουργία ενός οχήματος βασισμένου στον ιό FV το οποίο να περιέχει το στοιχείο S/MAR 2000. Το όχημα αυτό θα περιέχει το γονίδιο αναφοράς GFP (green fluorescent protein), υπό τον υποκινητή Mscv και το στοιχείο S/MAR2000 στην αντίστροφη κατεύθυνση (pDFMscvF.SMAR2000r) με σκοπό τη μείωση του κινδύνου της παράπλευρης ενεργοποίησης γονιδίων στο σημείο ενσωμάτωσης των φορέων FV. Έπειτα θα πραγματοποιηθεί εισαγωγή του οχήματος pDFMscvF.SMAR2000r, παρουσία του στοιχείου S/MAR σε κύτταρα 293T για την παραγωγή vector stocks και εισαγωγή αυτών σε κύτταρα Ηela για τη μελέτη της δράσης του οχήματος που κατασκευάσαμε. Η ανάλυση της έκφρασης του γονιδίου αναφοράς GFP στα κύτταρα αυτά θα γίνει με τη χρήση της κυτταρομετρίας ροής. / -

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