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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.
431

Application of the Prince's idea: conservation of Kam Tin

Cheung, Wai-chuen., 張偉傳. January 1993 (has links)
published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning
432

Neighborhood conservation around the world heritage sites in Nepal: a study on the Kathmandu Palace Square

Bhattarai, Vibha. January 2003 (has links)
published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning
433

Privacy-preserving computation for data mining

Brickell, Justin Lee 01 June 2010 (has links)
As data mining matures as a field and develops more powerful algorithms for discovering and exploiting patterns in data, the amount of data about individuals that is collected and stored continues to rapidly increase. This increase in data heightens concerns that data mining violates individual privacy. The goal of data mining is to derive aggregate conclusions, which should not reveal sensitive information. However, the data-mining algorithms run on databases containing information about individuals which may be sensitive. The goal of privacy-preserving data mining is to provide high-quality aggregate conclusions while protecting the privacy of the constituent individuals. The field of "privacy-preserving data mining" encompasses a wide variety of different techniques and approaches, and considers many different threat and trust models. Some techniques use perturbation, where noise is added (either directly to the database that is the input to the algorithm or to the output of queries) to obscure values of sensitive attributes; some use generalization, where identifying attributes are given less specific values; and some use cryp- tography, where joint computations between multiple parties are performed on encrypted data to hide inputs. Because these approaches are applied to different scenarios with different threat models, their overall e ectiveness and privacy properties are incomparable. In this thesis I take a pragmatic approach to privacy-preserving data mining and attempt to determine which techniques are suitable to real-world problems that a data miner might wish to solve, such as evaluating and learning decision-tree classifiers. I show that popular techniques for sanitizing databases prior to publication either fail to provide any meaningful privacy guarantees, or else degrade the data to the point of having only negligible data-mining utility. Cryptographic techniques for secure multi-party computation are a natural alternative to sanitized data publication, and guarantee the privacy of inputs by performing computations on encrypted data. Because of its heavy reliance on public-key cryptography, it is conventionally thought to be too slow to apply to real-world problems. I show that tailor-made protocols for specific data-mining problems can be made fast enough to run on real-world problems, and I strengthen this claim with empirical runtime analysis using prototype implementations. I also expand the use of secure computation beyond its traditional scope of applying a known algorithm to private inputs by showing how it can be used to e ciently apply a private algorithm, chosen from a specific class of algorithms, to a private input. / text
434

Harmony in marriage: integrating sustainable solutions into historic house museums without interfering with the historic fabric

Bolliger, Serena Gigliola 09 September 2014 (has links)
Historic buildings live a double life between climate-adapted largely-passive structures and draughty, poorly-maintained ones. Preservation professionals argue that preserving these structures is more resource effective than constructing new buildings, and that pre-electricity structures were built to take advantage of climate and geography, using passive technologies to perform efficiently. Modern technologies have also been adopted- electrical lights, air conditioning, fire alarms - as a natural progression of inhabitation. Yet in historic house museums, there is still the promise of historic representation, one unmarred by ‘inauthentic’ additions. If modern and past technological changes have been accepted and integrated, how is the historic house museum not a ‘living building culture’? And if house museums are indeed a living building culture, why not allow a more flexible representation of our historic properties if they are interpreted with integrity and honesty? The EPA estimates that buildings represent 65% of the U.S. electricity use, and predictions estimate 80% of the 2030 building stock exists today. If we truly plan to reduce our energy consumption, we must confront the reality that existing buildings are a significant contributor to our output. If, as curators, it is our hope for historic buildings to represent preservation, then we must admit that in preserving the past for the future, we must begin by preserving our future. This thesis analyses the opportunities and risks for historic house museums to respect their historic interpretation but adapt to changing conditions. Examples of energy efficiency strategies both historic and current, will be examined in historic structures, illustrating that caretakers of historic buildings are making value judgments about the future of their property, in terms of environmental, fiscal and historical sustainability. This thesis includes the analysis of a case study historic house museum in Austin, Texas, the French Legation Museum, which is used as a base model for estimating energy efficiency gains from the adoption of some low-energy technologies. Calculations based on this information indicate which integrations and additions could offer the greatest return on investment for this historic building to operate as or more efficiently than a modern code construction without visible or egregious alteration to the historic fabric. / text
435

Biochemical and gelation properties of fish protein isolate prepared under various pH and ionic strength conditions

Thawornchinsombut, Supawan 17 September 2004 (has links)
A novel method for isolating fish proteins by shifting pH to high acid or high alkali pH was the focus of the study. Biochemical and physicochemical properties of various pH-treated soluble fish proteins as a function of ionic strength were determined. Effect of ionic strength and various storage conditions on gelation properties and stabilization of fish protein isolate (FPI) were also elucidated. At low ionic strength (IS 10 mM NaCl), the solubility of Pacific whiting (PW) proteins was low between pH 5 and 10, but increased significantly as the pH was shifted to either acidic or alkaline pH. The isoelectric point (pi) shifted toward acidic direction as IS increased to 600 mM. High IS (600 mM NaCl) resulted in protein aggregation at low pH but improved myosin heavy chain (MHC) solubility at pH 6 - 10. Changes in total sulfhydryl (SH) content and surface hydrophobicity (S [subscript o]) were associated with the different molecular weight distributions of the soluble proteins. At pH 4 and IS 10-100 mM, MHC was soluble but degraded. At pH 10, the formation of high MW polymers was observed at IS [greater than or equal to] 150 mM. Gels obtained from FPI prepared at pHl1/IS150 and conventional surimi (CS) were superior to FPI prepared at pH 3 and/or other IS levels. There was no correlation between protein solubility and gel properties of FPI. Gelation mechanisms of acid and alkali-treated FPI were identical under the same IS condition. FPI prepared at pH 3 or 11 could be partly refolded at pH 7. No significant difference in texture was observed between alkali-treated protein isolates (AKPI, pH 11) kept frozen at pH 5.5 and 7.0. Strongest gel was found for AKPI with cryoprotectants (C) and without freeze/thaw (FT) cycles at both pH storage (5C & 7C), while poor gel was obtained from AKPI without cryoprotectants (NC) and with FT (5NC-F & 7NC-F). 5NC-F & 7NC-F demonstrated the lowest S [subscript o] and total SH probably suggesting that proteins were more aggregated as a result of hydrophobic interactions and disulfide bonds. Scanning electron microscope (SEM) revealed the most discontinuity of gels from AKPI without cryoprotectants and with FT and showed less protein stability when stored at pH 5.5 than at neutral pH. Raman spectral analysis demonstrated that refolding of AKPI by pH adjustment to 7.0 was achieved, but not identical to the native protein. CS contained higher α-helix content (~50%) than AKPI (~20-30%). Frozen storage induced a decrease and an increase in the α-helix of CS and AKPI samples, respectively. Alkali-treated proteins were slightly less stable than CS during frozen storage. / Graduation date: 2005
436

Preserving and Surfacing Rotted Wood and Charcoal

Hall, E. T., Jr. 04 1900 (has links)
No description available.
437

A funding source guide for historic preservation projects in South Dakota

Skypala, Madeleine January 1997 (has links)
Budget cuts for historic preservation and other humanities based projects are occurring on the federal, state, and local levels. Funding sources that historically supported these types of projects are being scaled back and eliminated. Given the current political trends, this situation will probably continue for the next several years. It is, therefore, imperative that funding sources are identified and solicited if current preservation efforts are to continue.This creative project is a funding source guidebook for historic preservation projects for the historic preservation constituency of South Dakota. This guidebook explains grants and the grant solicitation process, identifies potential funding sources and programs for historic preservation projects, and gives information about grant, funding source, and proposal writing. / Department of Architecture
438

Thermal Conductivity of Cryoprotective Agents with Applications to Cryopreservation by Vitrification

Ehrlich, Lili E. 01 April 2017 (has links)
Cryopreservation is the preservation of biomaterials at extremely low temperatures. It is the only alternative for long-term storage of high quality biomaterials, with applications to biobanking and transplant medicine. Cryopreservation success revolves around the control of ice formation, which is known to be harmful. Ice formation is a path-dependent phenomenon, affected by the thermal history and presence of nucleation promotors. Cryoprotective agents (CPAs) are commonly added to the biomaterial to be preserved, in order to suppress ice formation and inhibit its growth during the cryopreservation protocol. Ice-free cryopreservation can be achieved in large-size systems when the biomaterial is loaded with a high CPA concentration solution and cooled rapidly, in a process that is known as vitrification (vitreous means glassy in Latin). During vitrification, the CPA viscosity increases exponentially with decreasing temperature, while the material is cooled to deep cryogenic temperatures faster than the typical time scale for crystallization. The material can potentially be stored indefinitely at such low temperatures. Large-size vitrification is associated with three competing needs on the CPA concentration. Since the cooling rate at the center of the specimen decreases with the increasing specimen size due to the scaling conductive resistance, higher CPA concentrations may be required to suppress crystallization in larger specimens. Higher CPA concentration generally requires lower cooling rates to avoid ice crystallization. On the other hand, since CPAs are potentially toxic, the lowest possible CPA concentration is required to maintain viability and facilitate functional recovery. The decrease in CPA concentration combined with an increase in cooling rates may intensify thermo-mechanical stress due to non-uniform thermal contraction to the point of structural destruction. Essentially, successful cryopreservation represents the outcome of an optimization problem on the composition and concentration of the CPA cocktail. The work presented in this thesis combines an experimental study on the thermal conductivity of relevant materials, and a theoretical study to identify the effects of the measured values on cryopreservation protocols. The unique contributions presented as the initial stage of the experimental study are: (i) the modification of the cryomacroscope and creation of an experimental program to make thermal conductivity measurements of CPA based on the existing transient hot wire technique, (ii) to develop a protocol for making thermal conductivity measurements during rewarming portion of the cryoprotocol, and (iii), to begin generating a data bank of thermal conductivity of CPA and materials used in cryopreservation. Thermal conductivity measurements are presented for the CPA Dimethyl Sulfoxide (DMSO), over a concentration range of 2M to 10M, in a temperature range of -180°C to 25°C. Samples of 2M to 6M DMSO were found to crystallize at quasi-steady cooling rates, while samples of 7.05 to 10M were found to vitrify. Thermal conductivities of the crystallized and vitrified material reach a tenfold difference at -180°C. The quality of measurements using the presented technique has been verified theoretically by means of finite element analysis (FEA) using the commercial code ANSYS. This experimental study is expanded to the study of thermal conductivity of the CPA cocktail DP6--a mixture of 3M DMSO and 3M propylene glycol, which has drawn significant attention in the cryobiology community in recent times. The unique contributions are the first thermal conductivity measurements reported in literature of the combined effect of DP6 with synthetic ice modulators (SIMs), including 6% 1,3Cyclohexanediol, 6% 2,3Butanediol, and 12% PEG400. Results of this study demonstrate that the thermal conductivity may vary by three fold between the amorphous and crystalline phases of DP6 below the glass transition temperature. Results of this study further demonstrate the ability of SIMs to decrease the extent of crystallization in DP6, even at subcritical cooling and rewarming rates. The accompanying theoretical investigation focuses on cryopreservation in a kidney model, in effort to explore how the thermal history is affected by variations in the measured thermal conductivity. This analysis is based on FEA using the commercial code ANSYS. In particular, the unique contributions of this study are: (i) thermal analysis of a vitrifying rabbit kidney based on an established rabbit-kidney cryopreservation protocol, and (ii), exploring scale-up thermal effects to a human-size organ. This represents a 21-fold increase in organ size. Results indicate that even in the case of the human kidney, cooling rates remain high enough in all parts of the kidney to prevent ice formation at temperatures above -100oC.
439

Novel vs clinical organ preservation solutions: improved cardiac mitochondrial protection

Ferng, Alice S., Schipper, David, Connell, Alana M., Marsh, Katherine M., Knapp, Shannon, Khalpey, Zain 26 January 2017 (has links)
Background: Heart transplantation remains the gold standard for end-stage heart failure, with current ex vivo organ storage times limited to 4 to 6 h before critical tissue damage occurs. Many preservation solutions exist in an attempt to limit both ischemic and reperfusion damage. In order to compare the effects of various storage solutions, mitochondrial function can be used to provide a sensitive analysis of cellular metabolic function. Methods: Experimental plates were seeded with cardiac myoblasts and kept in suspended animation for either 4 or 8 h at either 4(o) or 21 degrees C, in Celsior (R), Perfadex (R), or Somah storage solutions. Cells were then reanimated for 1 h at 37 degrees C to simulate a reperfusion or clinical transplant scenario. Cellular bioenergetics were measured immediately thereafter to examine biochemical differences between preservation solutions and their effectiveness on preserving metabolic function. Results: The oxygen consumption rates of Somah solution were significantly higher than Celsior (R) and Perfadex (R) at 4 degrees C, with the exception of Perfadex (R) at 4(o) for 4 h. This effect was sustained up to 8 h. At 21 degrees C, oxygen consumption rates of Somah solution are significantly higher than Celsior (R) and Perfadex (R) at basal conditions after 4 h, but this effect is not sustained after 8 h. Conclusions: The purpose of this experiment was to study the efficacy of various preservation solutions on a mitochondrial level. The significantly higher oxygen consumption rates of Somah at 4 degrees C suggests that Somah solution may have the ability to protect cellular mitochondrial integrity, improve transplanted organ function by reducing ischemic-reperfusion injury, and thereby improve transplant outcomes. Given that Somah offers benefits over Celsior (R) and Perfadex (R) at 4 degrees C, it should be a target in future organ preservation solution research.
440

Alveolar Ridge Dimension Analysis Following Socket Preservation Using Clinical Assessment and Cone Beam Computed Tomography (CBCT).

Duggan, Sayward 12 May 2001 (has links)
AIM: Extraction of a tooth can lead to alveolar ridge resorption which can be minimized by socket preservation. The aim of this study is to analyze vertical and horizontal alveolar ridge dimensions clinically and by CBCT immediately following extraction and 3-4 months following socket preservation. METHODS: The preserved group (P) consisted of 20 patients with1-2 non-molar teeth requiring extraction with socket preservation, while the control group (C) consisted of 5 patients requiring extraction alone. An acrylic stent was fabricated presurgically in order to measure vertical and horizontal ridge dimensions clinically and radiographically immediately following extraction and 3-4 months following socket preservation. RESULTS: Overall, P sites gained ridge height and lost minimal ridge width over 3-4 months, while C sites lost both ridge height and width. Preserved sites in which the teeth were extracted due to caries had the most significant gain in the radiographic vertical occlusal dimension (RVO). Overall, high correlations were found between the clinical and radiographic measurements at the initial surgery and at the 3-4 month follow up. CONCLUSIONS: The preserved group had minimal ridge resorption and more socket bony fill when compared to the non-preserved group 3-4 months following tooth extraction, especially when the tooth was extracted due to caries. Additionally, the CBCT can be a useful diagnostic tool to evaluate socket preservation healing, as it compares well to clinical assessments of socket healing.

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