Qi, Huijie = 用于脫氧核糖核酸分子精确识别的Förster共振能量转移与光电压效应相结合的DNA-量子点分子光电开关 / 齐慧杰. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Abstracts in English and Chinese. / Qi, Huijie = Yong yu tuo yang he tang he suan fen zi jing que shi bie de Förster gong zhen neng liang zhuan yi yu guang dian ya xiao ying xiang jie he de DNA-liang zi dian fen zi guang dian kai guan / Qi Huijie. / Abstract --- p.i / Acknowledgements --- p.iv / Table of contents --- p.v / List of Figures --- p.ix / List of Tables --- p.xiii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.1.1 --- Nanotechnology and nanomaterials --- p.1 / Chapter 1.1.2 --- "Semiconductor quantum dots: optical properties, preparation and applications" --- p.3 / Chapter 1.1.2.1 --- Preparation --- p.3 / Chapter 1.1.2.2 --- Applications --- p.5 / Chapter 1.1.3 --- Quantum dot-based DNA recognition --- p.10 / Chapter 1.1.3.1 --- Forster resonance energy transfer --- p.11 / Chapter 1.1.3.2 --- Bioimmobilization technique --- p.13 / Chapter 1.1.3.3 --- Highlights on Quantum dot-based DNA recognition --- p.14 / Chapter 1.2 --- Objective and methodology --- p.16 / Chapter 1.2.1 --- Objective --- p.16 / Chapter 1.2.2 --- General methodology --- p.17 / References --- p.19 / Chapter Chapter 2 --- Instrumentation --- p.23 / Chapter 2.1 --- Introduction --- p.23 / Chapter 2.2 --- Atomic Force Microscopy --- p.23 / Chapter 2.2.1 --- Principle of Atomic Force Microscopy --- p.24 / Chapter 2.2.2 --- Instrumentation --- p.29 / Chapter 2.3 --- Absorption and Fluorescence spectroscopy --- p.30 / Chapter 2.3.1 --- Basic Principle --- p.30 / Chapter 2.3.2 --- Instrumentation --- p.33 / Chapter 2.4 --- I-V characteristic --- p.36 / Chapter 2.4.1 --- Basic principle --- p.36 / Chapter 2.4.2 --- Instrumentation --- p.36 / Chapter 2.5 --- Other instrumentations --- p.37 / References --- p.38 / Chapter Chapter 3 --- Preparation of DNA/QD network systems --- p.39 / Chapter 3.1 --- Introduction --- p.39 / Chapter 3.2 --- Preparation of DNA/QD network conjugates in solution --- p.39 / Chapter 3.2.1 --- Experimental --- p.39 / Chapter 3.2.2 --- Characterization --- p.41 / Chapter 3.3 --- Preparation of DNA/QD network on substrates --- p.44 / Chapter 3.3.1 --- Experimental --- p.44 / Chapter 3.3.2 --- Characterization --- p.46 / Chapter 3.4 --- Summary --- p.49 / References --- p.50 / Chapter Chapter 4 --- Fluorescence and I-V characteristics for DNA/QD systems --- p.51 / Chapter 4.1 --- Introduction --- p.51 / Chapter 4.2 --- Experimental --- p.52 / Chapter 4.2.1 --- Patterned Au electrodes --- p.52 / Chapter 4.2.2 --- Electric field induced assembly --- p.52 / Chapter 4.3 --- Results and Discussion --- p.55 / Chapter 4.3.1 --- Optical studies of DNA/QD systems --- p.55 / Chapter 4.3.1.1 --- Optical characteristics of QDs used --- p.55 / Chapter 4.3.1.2 --- Optical studies of DNA/QD network systems in solution --- p.56 / Chapter 4.3.1.3 --- Optical studies of DNA cross-linked QD monolayer on substrates --- p.58 / Chapter 4.3.2 --- PV characteristics --- p.62 / Chapter 4.4 --- Summary --- p.64 / References --- p.66 / Chapter Chapter 5 --- DNA-quantum dot molecular opto-electronic switch with combined Forster resonance energy transfer and photovoltaic effect --- p.68 / Chapter 5.1 --- Introduction --- p.68 / Chapter 5.2 --- Experimental --- p.69 / Chapter 5.2.1 --- Preparation of DNA/QD molecular switch in solution --- p.69 / Chapter 5.2.2 --- Preparation of platform of molecular optoelectronic switch --- p.72 / Chapter 5.2.3 --- EFIA --- p.73 / Chapter 5.3 --- Results and Discussion --- p.73 / Chapter 5.3.1 --- Optical studies of molecular switch constructed of DNA/QD/Cy5 system --- p.73 / Chapter 5.3.1.1 --- Studies on optical properties of molecular switch as well as sole FRET effect between QD and Cy5in solution --- p.73 / Chapter 5.3.1.2 --- Optical studies of dsDNAs cross-linked QD monolayer on substrates with presence of Cy5 --- p.79 / Chapter 5.3.2 --- Studies on FRET mediated PV effect of DNA/QD/Cy5 molecular optoelectronic switch --- p.80 / Chapter 5.4 --- Summary --- p.82 / References --- p.83 / Chapter Chapter 6 --- Conclusions and Future Work --- p.84 / Chapter 6.1 --- Conclusions --- p.84 / Chapter 6.2 --- Future work --- p.85

Estágio realizado na Fraunhofer SIT - e orientado pelo Dr. Huajian Liu e pelo Dr. Marcel Schäfer / Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 2012

Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

<p>In today's video delivery and broadcast networks, issues of copyright protection have become more urgent than in analog times, since the copying of digital video does not result in the decrease in quality that occurs when analog video is copied. </p><p>One method of copyright protection is to embed a digital code, a"watermark", into the video sequence. The watermark can then unambiguously identify the copyright holder of the video sequence. Watermarks can also be used to identify the purchaser of a video sequence, which is called "fingerprinting". </p><p>The objective of this master thesis was to implement a program that would insert watermarks into video sequences and also detect if a given video sequence contains a givenwatermark. </p><p>The video standard I chose to use was the H.264 standard (also known as MPEG4 AVC) as it offers a significant efficiency improvement over the previous video compression standards. </p><p>A couple of tests that can be considered representative for most image manipulations and attacks were performed. The program passed all tests, suggesting that the watermarking mechanism of this thesis can be expected to be rather robust, at least for the video sequence used. By looking at the watermarked video sequences and comparing them to the originals, or measuring the signal to noise ratio, one can also see that the watermarks are unobtrusive. The execution times were also measured. Compared to coding and decoding a H.264 video stream, the time it takes to insert and extract watermarks was much less. Calculating a threshold takes roughly double the time as decoding the sequence, though.</p>

<p>Media such as movies and images are nowadays produced and distributed digitally. It is usually simple to make copies of digital content. Consequently illegal pirate copies can be duplicated and distributed in large quantities. One way to deter authorized content receivers from illegally redistributing the media is watermarking. If individual watermarks are contained in the digital media and a receiver is a pirate and redistributes it, the pirate at the same time distributes his identity. Thus a located pirate copy can be traced back to the pirate. The watermarked media should otherwise be indistinguishable from the original media content.</p><p>To distribute media content scalable transmission methods such as broadcast and multicast should be used. This way the distributor will only need to transmit the media once to reach all his authorized receivers. But since the same content is distributed to all receivers the requirement of individual watermarks seems to be contradictory.</p><p>In this thesis we will show how individually watermarked media content can be transmitted in a scalable way. Known methods will be reviewed and a new method will be presented. The new method is independent of what type of distribution that is used. A system with robust watermarks that are difficult to remove is described. Only small parts of the media content will be needed to identify the pirates. The method will only give a small data expansion compared to distribution of non-watermarked media.</p><p>We will also show how information theory tools can be used to expand the amount of data in the watermarks given a specific size of the media used for the watermarking. These tools can also be used to identify parts of the watermark that have been changed by deliberate deterioration of the watermarked media, made by pirates.</p> / Report code: LiU-Tek-Lic-2005:67.

In today's video delivery and broadcast networks, issues of copyright protection have become more urgent than in analog times, since the copying of digital video does not result in the decrease in quality that occurs when analog video is copied. One method of copyright protection is to embed a digital code, a"watermark", into the video sequence. The watermark can then unambiguously identify the copyright holder of the video sequence. Watermarks can also be used to identify the purchaser of a video sequence, which is called "fingerprinting". The objective of this master thesis was to implement a program that would insert watermarks into video sequences and also detect if a given video sequence contains a givenwatermark. The video standard I chose to use was the H.264 standard (also known as MPEG4 AVC) as it offers a significant efficiency improvement over the previous video compression standards. A couple of tests that can be considered representative for most image manipulations and attacks were performed. The program passed all tests, suggesting that the watermarking mechanism of this thesis can be expected to be rather robust, at least for the video sequence used. By looking at the watermarked video sequences and comparing them to the originals, or measuring the signal to noise ratio, one can also see that the watermarks are unobtrusive. The execution times were also measured. Compared to coding and decoding a H.264 video stream, the time it takes to insert and extract watermarks was much less. Calculating a threshold takes roughly double the time as decoding the sequence, though.

Soil and groundwater is the final receptor environment of contamination on land, especially easy to contaminate groundwater aquifers, because of the underground environment often obscure, it is difficult to clarify the scope of pollution, in addition, the transport and chemical transformation process are also difficult to evaluate. Resulting that although consumes on huge cost and materials, and times on oil contaminated site investigation and remediation, obtaining the solution of the problem is still hard. In this study, it combines with the environmental site assessment and the triad rapid investigation, the establishment of site contamination conceptual model, the key designated contaminated area, collect samples of the implementation for laboratory analysis, Moreover, use cyclic evaluation process, continuously updated site conceptual model, to clarify the distribution of contaminated sites, impact of pollution, hydro-geological characteristics and pollution sources. It also discussed the effective reduction of pollution critical area, to obtain high-density results, in order to improve sampling and analysis to make the efficiency of the case of site investigation, and using environmental forensic techniques to determine and provide the evidence of pollution sources. ESA phase I implements the key results of the preliminary delineation of contaminated areas, soil and groundwater pollution concerns and possible sources of material. ESA phase II evaluates preliminary assessment of sites contaminated soil contamination is a high carbon number of oil and contaminants move to the surface to deeper soil 9 m at the lower, deeper pollution range is unknown. Groundwater test results garnered less than control standards, but the detection of trace gas station in MTBE, it is included in the possible sources of pollution. Taking ESA phase II assessment in a further analysis, the soil contaminants are TPHC10-C40 based, contamination depth of 8m, gas station area within the tank and pipeline testing values are low, there is no sign of oil leakage. Pollution more than 5m in depth the most serious, TPH concentrations in general are 10,000 mg/kg or more, the depth of 5m and the following have been significantly reduced, TPH concentrations than in the 5,000 mg/kg or less. Interviews showed that the specific relationship between the people, suspected underground oil refining line set 40 years ago, suspected of shipping oil from the waste obtained after the hull, after the system by then resold for profit. Identification of pollution sources than the results, TPHC10-C40 carbon number distribution or pattern of the peak are more similar to diesel. TIC illustration showed that the distillate oil mixture for two, than the peak apex, suggesting that the low-carbon should be diesel fuel, and the high-carbon would be fuel. Pr/Ph ratio than, presumably with the CPC diesel from different sources. Alkyl bicyclic sesquiterpene class fingerprint comparison results, the shape of the fingerprint sample slightly different, but the main features of the same types of compounds. Analysis of aromatic compounds, indicators showed that the samples compound ratio of methyl phenanthrene and methyl dibenzothiophene isomers, dibenzothiophene, and phenanthrene isomers are closer. Integrated fingerprint analysis (fingerprinting) results, similar to the site characteristics of pollutants, for the same pollution source. The site is semi-volatile pollutants, substances insoluble in water, more stored in the main pollution silt/clay layer, subject to geological conditions, ground remediation techniques are more difficult to grasp in the transmission path, remediation systems that require high density, break through the bottleneck transmission path, but a majority of sites on private land, during the remediation process it is difficult to obtain the burgage, therefore, it would be fit the inappropriate comprehensive ground handling. Subsequent remediation plan can be removed towards the high pollution of soil pollution, and long-term monitoring of permeable reactive barrier type with natural degradation. Recommendations for the future studies can be dust inhalation and skin contact with soil, groundwater ingestion, inhalation and skin contact exposure pathways for risk assessment, site management provided a basis for administrative control.

Cores and sediment traps collected from Kao-ping Canyon were used to reconstruct historical record of PAHs contamination and find out the possible sources, distributions, trends and flux of PAHs. The sedimentary record of PAHs shows that the average concentration of total PAHs was 310 ng/g dry wt. (264¡ã364 ng/g) which was lower than coasts of the other countries. According to diagnostic ratios and statistical analysis, we identify sources of PAHs and suggest that all up-cores were dominated by petrogenic sources, but all down-cores except for C980 and S1 were tended to pyrogenic or mixed sources. In contrast, both C980 and S1 were showed higher perylene/£UPAHs (%), which suggests that biogenic sources dominate in C980 and S1. In comparison with sediment quality guidelines (SQGs), the PAHs concentrations of all sediment cores weren¡¦t exceeded the criteria, which suggests that no evident adverse biological effects exist caused by PAHs in Kao-ping Canyon. It shows that the transition from coal to petroleum fuel use corresponding to the total concentrations of PAHs decrease recorded during 1893-1935 period in the sediment core. A PAHs concentration peak also recorded during the World War ¢º, 1893-1935. Because of increase of importing fossil fuel and the growth of heavy industrials in Kao-Ping area, the total concentrations of PAHs were shown evidence of increase again since 1950s in the core from Kao-ping Canyon. The average PAHs flux in the upper and lower mooring deployed in Kao-ping Canyon were 66 and 108 £gg/m2/d, respectively, which were higher than coasts of the other countries. The PAHs sources of sinking particles were dominated by petrogenic sources which were as similar sources as all up-cores.

Remote Analyse von Netzwerken hinter Firewalls und Firewallsystemen.

Fingerprints play an important role in biometrics and cryptography. Their creation might be based on one-way hash functions, which should usually also be collision-resistant. But users tend to draw less attention at those fingerprints - so an attacker might hand out a similar fingerprint in order to spoof identity. The main ideas for creating such 'fuzzy fingerprints' and the creation algorithm itself are discussed in this lecture. The demonstration of the tool, that produces fuzzy fingerprints shows the practical background of this technique. / Fingerabdrücke besitzen sowohl in der Kryptographie als auch in der Biometrie eine große Bedeutung. In kryptographischen Anwendungen werden diese durch Einweg-Hash-Verfahren erzeugt, die für bestimmte Anwendungen auch kollisionsresitent sein müssen. In der Praxis schenken Benutzer diesen Fingerprints weit weniger Aufmerksamkeit - oft genügt es nur hinreichend ähnliche Fingerprints auszugeben, um die Nutzer zu täuschen Die Kriterien, die dabei erfüllt sein müssen und die Erzeugung dieser "Fuzzy Fingerprints" sind Hauptbestandteil dieses Vortrags. Durch die Demonstration eines Tools im praktischen Einsatz wird dieser abgeschlossen.