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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.
491

Integrated Reservoir Characterization: Offshore Louisiana, Grand Isle Blocks 32 & 33

Casey, Michael Chase 2011 May 1900 (has links)
This thesis integrated geology, geophysics, and petroleum engineering data to build a detailed reservoir characterization models for three gas pay sands in the Grand Isle 33 & 43 fields, offshore Louisiana. The reservoirs are Late Miocene in age and include the upper (PM), middle (QH), and lower (RD) sands. The reservoir models address the stratigraphy of the upper (PM) sand and help delineate the lower (RD) reservoir. In addition, this research addresses the partially depleted QH-2 reservoir compartment. The detailed models were constructed by integrating seismic, well log, and production data. These detailed models can help locate recoverable oil and gas that has been left behind. The upper PM model further delineated that the PM sand has several areas that are shaled-out effectively creating a flow barrier within reservoir compartments. Due to the barrier in the PM-1 reservoir compartment, an area of potentially recoverable hydrocarbons remains. In Grand Isle 33, the middle QH sand was partially depleted in the QH-2 reservoir compartment by a series of development wells. Bottom hole pressure data from wells in Grand Isle 32 & 33 reveal that the two QH fault compartments are in communication across a leaking fault. Production wells in the QH-1 compartment produced reserves from the QH-2 compartment. The lower RD sand model helped further delineate the reservoir in the RD-2 compartment and show that this compartment has been depleted. The RD model also shows the possible presence of remaining recoverable hydrocarbons in the RD-1 compartment. It is estimated that about 6.7 billion cubic feet of gas might remain within this reservoir waiting to be recovered. A seismic amplitude anomaly response from the QH and RD sands is interpreted to be a lithologic indicator rather than the presence of hydrocarbons. Amplitude response from the PM level appears to be below the resolution of the seismic data. A synthetic seismogram model was generated to represent the PM and surrounding sands. This model shows that by increasing the frequency of the seismic data from 20 Hz to a dominant frequency of 30 Hz that the PM and surrounding sands could be seismically resolvable. Also the PM-1 compartment has possible recoverable hydrocarbons of 1.5 billion cubic feet of gas remaining.
492

none

Ping, Chong-zhi 07 August 2006 (has links)
Sustaining development is becoming one of the challenges to enterprises because concerns to the natural and human environments are always being overlooked by the enterprises which intend to get sustaining advantages, especially at the globalization competing situations among enterprises. In general, only part pictures of the sustaining development can be observed by the first department (personal department) from a private viewpoint. The second department (government) is always a stumbling block to the enterprises which intend to move to foreign countries. The third department (nonprofit organization) dedicates to the development of human well-beings and citizen aesthetics which can eventually become a part of business culture. Enterprises with the concept of sustaining development for environments should agree to the viewpoints of the second and the third departments and would like to melt those into their business cultures. By the melting, a coexistence concept for the enterprises, the society and the consumers can be developed, and the social responsibilities and duties may be brought into the enterprises further. Finally, it will become an active motivation force which accelerates business development and their social responsibility mission, and eventually becomes a global sustaining development for human beings. Taiwan¡¦s leading position of synthetic leather manufacture in the world has been replaced due to its higher domestic labor, land costs and enterprise out-moving. However, some companies of the industry is still developing and promising by taking the policies of producing centralization, variety, and high value-additive products. For facing world-wide competition in the future, the industry should have an overall strategy on the viewpoints of business administration and environmental policy. In this study, two approaches, namely business competition strategy and business environmental policy, were adopted to develop subjects for obtaining a sustainable development to the synthetic leather industry. Investigation results indicate that a world-wide plumb-integration on cost competition, and producing centralized, high-variety, and high value-additive products might be a practical strategy for competing with the world plant mainland China. By a case study in this report, the strategy has been shown to be effective for abating negative impacts from current situations of world trade liberalization, inside cost promotion, and enterprise out-moving Pollution prevention has been regarded as a burden to enterprises. However, investigation results also indicate that by planning and implementation of environmental policies such as process waste reduction, energy saving, clean production, and development of environment-friendly products, the synthetic leather industry can find a more promising way.
493

none

Chiu, Nu-Chu 24 August 2006 (has links)
Abstract Taiwan Synthetic Resin industry filed, undergoing fifty hard years, this is a mature industry and most of companies have been built up a certain scale of production. Since 1997 the China government combined economic reform with open policy to create a rapid economy growth. With the appeal of market superiority rising and low production cost, truly attracts many inverters enter the target market. Under such strong market competitive, some of Taiwan Synthetic Resin companies have successfully transferred into a high-tech industrial territory, some of companies were standing on their original basis to improve its competition ability. Hence, there is obviously difference of the final business performance in between them. This thesis is based on the case study for Q company, engaged in manufacturing Synthetic Resin related products. The research methodologies take various theoretical analyses such as the ¡§Value Chain¡¨ model of Michael Porter and ¡§Strategic Alliance¡¨ to investigate the business strategy of those listed companies and OTC of Taiwan Synthetic Resin industry. Hope this research should provide useful information about the related strategic usage and future development of the Synthetic Resin industry. The key points of finding in this study may be summarized as under: 1) The technical resource of Taiwan Synthetic Resin industry is mainly demanded on technical alliance and the R&D capability is still under developing. 2) The rapid economic growth and development of the Mainland China caused more difficult environment for Taiwan company future development in the business transformation strategy. 3) The enterprise resource is key success factor in achieving competitive advantages in operation, technology and marketing in the industry field. Key words: Synthetic Resin¡BValue Chain¡BStrategic Alliance¡BBusiness transformation
494

Hingeless flow control over an airfoil via distributed actuation

Agrawal, Anmol 25 April 2007 (has links)
An experimental investigation was undertaken to test the effectiveness of a novel design for controlling the aerodynamics of an airfoil. A synthetic jet actuator (SJA) was placed inside a NACA 0015 airfoil with its jet at 12.5% of the chord length, hereby referred to as the leading edge actuator. Four centrifugal fans across the span were mounted at 70% of the chord and the jet formed by them was located at 99% of the chord, hereby referred to as the trailing edge actuator. The effects of these actuators on the aerodynamic properties were studied, separately and then in conjunction, with varying angles of attack. The leading edge actuator delays the onset of stall up to 24 degrees, the maximum angle of attack that could be attained. The control of the aerodynamics was achieved by controlling the amount of separated region. There was no effect of the actuation at lower angles of attack. The trailing edge actuator provides aerodynamic control at both low and high angles of attack. The study investigated the effect of jet momentum coefficient on the aerodynamic properties for various angles of attack. The data obtained shows that lift control (in both positive and negative direction) was achieved even at low angles. The actuator enhances the aerodynamic properties by changing the pressure distribution as well as by delaying flow separation. Study of the combined actuation shows that the synthetic jet actuator was very effective in delaying stall when the trailing edge jet was ejected from the upper surface. For the case when the jet is ejected from the lower surface, there is less control. This can be accounted for by the difference in aerodynamic loading for both cases.
495

Texture classification of SAR sea ice using the wavelet transform /

Yu, Qiyao, January 2001 (has links)
Thesis (M.Eng.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves 95-100.
496

Automatic detection of land cover changes using multi-temporal polarimetric SAR imagery

Zhang, Xiaohu, 张啸虎 January 2013 (has links)
Dramatic land-cover changes have occurred in a broad range of spatial and temporal scales over the last decades. Satellite remote sensing, which can observe the earth's surface in a consistent manner, has been playing an important role in monitoring and evaluating land-cover changes. Meanwhile, optical remote sensing, a common approach to acquiring land-cover information, is limited by weather conditions and thus is greatly constrained in areas with frequent cloud cover and rainfall. Recent advances in polarimetric SAR (PolSAR) provide a promising means to extract timely information of land-cover changes regardless of weather conditions. SAR satellite can pass through an area from different orbits, namely ascending orbit and descending orbit. The PolSAR images from the same orbit will have similar backscattering even with different incident angles. But if images are acquired from different orbits, the backscattering will vary greatly, which causes many difficulties to land cover change detection. The proposed algorithms in this study can perform land cover change detection in three situations: 1) repeat-pass images (image from the same orbit and with same incident angle, 2) images from the same orbit but with different incident angle, and 3) images from different orbits. Using images from different orbits will largely reduce the monitoring interval which is important in the surveillance of natural disasters. The present study proposes 1) a sub-pixel automatic registration technique, 2) an automatic change detection technique and 3) an iterative framework to process a time series of PolSAR images that can be applied to the PolSAR images from different orbits. Firstly, automatic registration is crucial to the change detection task because a small positional error will largely degrade the accuracy of change detection. The automatic registration technique is based on the multi-scale Harris corner detector. To improve the efficiency and robustness, the orientation angle differencing method is proposed to reject outliers. This differencing method has been proved effective even in the experiment of using PolSAR images from different orbits when less than 5% of the feature point matches are correct. Secondly, the change detection technique can automatically detect land-cover conversions and classify the newly input image. Hierarchical segmentation has been applied in the change detection which generates objects within the constraint of the previous classification map. Multivariate kernel density estimation is applied to classify newly input PolSAR image. The experiments show that the proposed change detection technique can mitigate the effect of polarimetric orientation shift when the PolSAR images are from different orbits, and it can achieve high accuracy even when complex local deformation is appeared. Lastly, the iterative framework, which integrates the automatic registration and automatic change detection techniques, is proposed to process a time series of PolSAR images. In the iterative process, no obvious decrease of classification accuracy is observed. Therefore, the proposed framework provides a potential treatment to derive land-cover dynamics from a time series of PolSAR images from different orbits. / published_or_final_version / Urban Planning and Design / Doctoral / Doctor of Philosophy
497

Adaptive multiscale estimation for fusing image data

Slatton, Kenneth Clinton 28 August 2008 (has links)
Not available / text
498

タイ、ラッチャブリ県ダムナンサドゥアクにおける農薬使用に及ぼすGAPプログラムの影響 / The GAP program and its effects on pesticide use in Damnoen Saduak, Ratchaburi, Thailand.

Javier, Eduardo Montano Moscoso 23 March 2015 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(農学) / 甲第19045号 / 農博第2123号 / 新制||農||1032 / 31996 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 縄田 栄治, 教授 舟川 晋也, 准教授 赤松 美紀 / 学位規則第4条第1項該当
499

Structure-Activity Study of a-N-Methylated SHU9119 Analogues, hMC4R/TNF-a Antagonists, and Mutational Studies of the Melanocyte Stimulating Hormone Receptor

Zingsheim, Morgan Robert January 2009 (has links)
The human melanocortin receptors (hMCRs) play a fundamental role in human behavior such as satiety, feeding, sexual and more. A set of SHU9119 peptide derivatives were studied for their structure-activity relationships. These peptides contained a sequential a-N-methylation amino acid scan.A second set of peptide derivatives intended to be used to create TNF-a; inhibition, via the melanocortin receptors. These peptides were shown to bind to all of the hMCR receptors, and only exhibit cAMP stimulation at hMC1R/hMC5R.The data from both of the sets of compounds illustrate that small changes in the stereochemistry of the SH9119 and TNF-a; derivatives cause drastic changes in the binding and the agonistic/antagonist properties of the compounds.This thesis determined the effect that hMC1R mutations have on the binding and cAMP response of well characterized ligands. This study ruled out 9 different residues for being the required for the cAMP response of the hMC1R.
500

Evaluation of Synthetic MRI for Clinical Use

Helmersson, Teresa January 2010 (has links)
Conventional Magnetic Resonance Imaging (MRI) is a qualitative method for obtaining images of softtissues in patients. Conventional MRI is the standard method used today and it results in gray-scaleimages in which the different magnetic properties of biological tissues determine the image contrast. However, the magnitude of the measured signal is only relative and therefore not directlycomparable between images. Synthetic MRI is a relatively new technique which can be used to postsynthesizedifferent images based on absolute measurement of several magnetic properties oftissues. Synthetic MRI can therefore provide quantitative information together with the contrastimages. In order to use synthetic MRI clinically an evaluation of the image quality and diagnostic ability isrequired. The purpose of this thesis is to evaluate if synthetic MRI and conventional MRI produceimages with equal contrast. A study was designed and conducted for statistical evaluation of contrast and Contrast-to-Noise Ratio(CNR) generated with different imaging methods. A total of 22 patients were examined using bothconventional MRI and synthetic MRI and the results were pairwise analyzed. The contrast and CNR could not be stated as equal for the imaging methods. Typically the contrastwas higher in the synthetic images for the T1 and T2 weighted images. This was not observed withCNR which suggests that the noise is higher in the synthetic images. The higher contrast obtained insynthetic images resulted in a better separation of different tissues using synthetic MRI. Thesynthetic T2 FLAIR images contained artifacts that are not good for clinical use. However the fact thatthe different imaging methods produce different image quality is not proven to be clinically decisive.

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