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Recently new contact lens materials have been introduced which are said to improve comfort by incorporating wetting agents either in a releasable or nonreleasable form. However, there is little information in the literature to demonstrate whether these claims are indeed true. In the present work, model lens materials based on poly(2-hydroxyethyl methacrylate) (pHEMA) and methacryloxypropyltris (trimethylsiloxy) silane(TRIS) were developed which incorporate releasable or crosslinked and therefore physically entrapped hyaluronic acid (HA) of various molecular weights as a wetting agent. Studies showed that uncrosslinked high molecular weight HA exhibited burst release kinetics with 80% release in less than 20 hours. While applicable for use in daily wear cycles, releasable wetting agents certainly would have very little effect on extended wear cycles, a common mode of wear. Protein adsorption results suggest however that the wetting agent resulted in no statistical change over the control material. Crosslinked and therefore physically entrapped HA, despite being only present in very small amounts, showed consistently lower water contact angles over four hours in comparison to controls, indicating that HA is present at the interface and was not being released over time. The presence of HA in the material was further confirmed by increases in the glass transition temperature measured by differential scanning calorimetry, increases in the stiffness as measured by Instron testing, and slight changes observed m both x-ray photoelectron spectroscopy and Fourier transform infrared spectra. This crosslinking procedure appeared to have no effect on optical transparency using 35 kDa HA whereas small decreases in optical transparency at higher wavelength were noted for the 169 kDa HA crosslinked material as measured by UV spectrophotometry. Most importantly, protein adsorption results indicated that the adsorption of all proteins studied was considerably decreased by the presence of the small amount of crosslinked HA. It is hypothesized that HA acts in a similar manner as PEO protein repulsion, where free HA chains are able to produce an environment which highly rejects protein adsorption. Significant decreases in lysozyme adsorption were also observed on model silicone hydrogel materials. The results suggest that these materials have significant potential for application in contact lens applications. / Thesis / Master of Applied Science (MASc)

This thesis presents a 2.4GHz image-reject downconverter fabricated in TSMC 0.25 1P5M CMOS process. The integrated active filter can not only filter out the image signal, but also reduce noise figure degraded by parasitic capacitance in the circuit. The differential LC oscillator fabricated in TSMC 0.35 1P4M CMOS process has properties of low phase noise and wide frequency turning range. Finally, a variable gain amplifier implemented in GCS GaAs HBT process was designed using signal summing architecture. The architecture is advantageous to reducing noise, distortion and increasing operating frequency. This thesis has studied what cause the difference between measurement and simulation for better performance in the future design.

¡@¡@This paper is refer to the chapter 1 to chapter 5 (except chapter 4 ) of the book, Monte Carlo Statistical Methods(second edition), the author is Robert and Casella(2004). The goal is to translate the chapter 1 to chapter 5 contents of this book into Chinese, modify the mistakes, add the details of the examples, translate the algorithm of the examples into Mathematica(7th) codes, and use the Simulated Annealing method to deal with the estimation of parameters by rounding data, and discuss the results. This paper provides Mathematica(7th) codes of almost every example, and show the actual results, so it can be regarded as a toolbook for those people who are interested in reading this book or may solve some problems related to those examples.

Because of the huge bandwidth of Ultra-Wideband (UWB) systems, in-band narrowband interference may hinder receiver performance. In this dissertation, sources of potential narrowband interference that lie within the IEEE 802.15.3a UWB bandwidth are presented, and a solution is proposed. To combat interference in Multi-Band OFDM (MB-OFDM) UWB systems, an analog notch filter is designed to be included in the UWB receive chain. The architecture of the filter is based on feed-forward subtraction of the interference, and includes a Least Means Squared (LMS) tuning scheme to maximize attenuation. The filter uses the Fast Fourier Transform (FFT) result for interference detection and discrete center frequency tuning of the filter. It was fabricated in a 0.18 µm process, and experimental results are provided. This is the first study of potential in-band interference sources for UWB. The proposed filter offers a practical means for ensuring reliable UWB communication in the presense of such interference. The Operational Transconductance Amplifier (OTA) is the predominant building block in the design of the notch filter. In many cases, OTAs must handle input signals with large common mode swings. A new scheme for achieving rail-to-rail input to an OTA is introduced. Constant gm is obtained by using tunable level shifters and a single differential pair. Feedback circuitry controls the level shifters in a manner that fixes the common mode input of the differential pair, resulting in consistent and stable operation for rail-to-rail inputs. As the new technique avoids using complimentary input differential pairs, this method overcomes problems such as Common Mode Rejection Ratio (CMRR) and Gain Bandwidth (GBW) product degradation that exist in many other designs. The circuit was fabricated in a 0.5µm process. The resulting differential pair had a constant transconductance that varied by only ±0.35% for rail-to-rail input common mode levels. The input common mode range extended well past the supply levels of ±1.5V, resulting in only ±1% fluctuation in gm for input common modes from -2V to 2V.

It has long been a tool of the LGBTQ rights movement to loudly proclaim and own one’s sexual orientation label. However, there is a new generation of young sexual minorities who feel a label is no longer necessary. Are these no-labelers headed in the right direction? Or are they hurting the fight for LGBTQ equality? / text

Sulfate is one of the most problematic ions present in reject brine in desalination systems due to its high potential of scale formation and membrane fouling; making it an obstacle in the application of zero liquid discharge. The ultra-high lime with aluminum process (UHLA) has shown to effectively remove sulfate. This research involves the study of sulfate removal from the nano-filtration unit in the zero liquid discharge system for inland desalination via a two-stage process using a calcium source to remove sulfate in the first stage and implementing the UHLA process in the second stage. The kinetics, equilibrium characteristics, and effects of different parameters on sulfate removal were studied. Kinetics of sulfate removal was studied on both stages of the process. The observation of fast kinetics in both stages indicated that removal kinetics is not a limitation for the application of the process. Equilibrium characteristics of the UHLA process were performed which revealed efficient sulfate removal at practical ranges of lime and aluminum doses. The effect of pH on sulfate removal in the process was studied. Results showed that sulfate removal in Stage 1 was independent of the pH of the solution while effective sulfate removal in Stage 2 was found to be above a pH of 11. The effect of initial sulfate concentrations on sulfate removal in Stage 1 was investigated and sulfate removal was mainly controlled by calcium sulfate solubility. The effect of initial chloride concentrations on sulfate removal in Stage 2 was evaluated and the results indicated that chloride has negligible effect on the removal of sulfate. Experiments concerning the effect of the recycle of calcium sulfate solids in Stage 1 showed an increase of the reaction rate. In contrast, the recycle of Stage 2 dry solids into Stage 2 revealed no effect on sulfate removal. An equilibrium model was developed to explain the equilibrium characteristics of Stage 2. It was found that a valid explanation for the chemistry of sulfate removal in Stage 2 was the formation of a solid solution consisting of ettringite and monosulfate. XRD analysis confirmed the formation of these solids.

This thesis investigates the computer vision application of live fish recognition, which is needed in application scenarios where manual annotation is too expensive, when there are too many underwater videos. This system can assist ecological surveillance research, e.g. computing fish population statistics in the open sea. Some pre-processing procedures are employed to improve the recognition accuracy, and then 69 types of features are extracted. These features are a combination of colour, shape and texture properties in different parts of the fish such as tail/head/top/bottom, as well as the whole fish. Then, we present a novel Balance-Guaranteed Optimized Tree with Reject option (BGOTR) for live fish recognition. It improves the normal hierarchical method by arranging more accurate classifications at a higher level and keeping the hierarchical tree balanced. BGOTR is automatically constructed based on inter-class similarities. We apply a Gaussian Mixture Model (GMM) and Bayes rule as a reject option after the hierarchical classification to evaluate the posterior probability of being a certain species to filter less confident decisions. This novel classification-rejection method cleans up decisions and rejects unknown classes. After constructing the tree architecture, a novel trajectory voting method is used to eliminate accumulated errors during hierarchical classification and, therefore, achieves better performance. The proposed BGOTR-based hierarchical classification method is applied to recognize the 15 major species of 24150 manually labelled fish images and to detect new species in an unrestricted natural environment recorded by underwater cameras in south Taiwan sea. It achieves significant improvements compared to the state-of-the-art techniques. Furthermore, the sequence of feature selection and constructing a multi-class SVM is investigated. We propose that an Individual Feature Selection (IFS) procedure can be directly exploited to the binary One-versus-One SVMs before assembling the full multiclass SVM. The IFS method selects different subsets of features for each Oneversus- One SVM inside the multiclass classifier so that each vote is optimized to discriminate the two specific classes. The proposed IFS method is tested on four different datasets comparing the performance and time cost. Experimental results demonstrate significant improvements compared to the normal Multiclass Feature Selection (MFS) method on all datasets.

Under 90-talet uppdagades övergödningsproblematiken i Östersjön, varför omgivande länder enades gällande åtgärder för att minska problemen. De svenska reningsverk som genom sina utsläpp av kväve och fosfor påverkade Östersjön tvingades då införa gränsvärden för kväve- och fosforutsläppen. Vid Arboga reningsverk, vars recipient är Arbogaån som mynnar i Galten, Mälaren, har kvävereducering sedan en tid tillbaka varit i drift. Dock krävdes från och med år 2012 att totalkvävehalten i utgående avloppsvatten ej översteg 15 mg tot-N/l. Införandet av detta gränsvärde resulterade i åtgärder för att minska kväveutsläppen.Rejektvattenbehandling är en vanlig metod för att minska halterna totalkväve i utgående avloppsvatten. Normalt utgör rejektvattnet 0,5–1,0 % av totala inflödet till reningsverket men 10–20 % av inkommande totalkvävebelastningen. I Arboga resulterade det nya gränsvärdet för totalkväveutsläpp i en nybyggnation av en rejektvattenbehandling utformad med fördenitrifikation. Detta innebär att rejektvattnet pumpas genom fyra zoner, två anaeroba följt av två aeroba. Ammoniumkvävet i inkommande vatten omvandlas genom detta processupplägg via nitrat till kvävgas.Denna studie syftade till att kartlägga rejektvattenbehandlingens effekt på halterna av totalkväve i utgående avloppsvatten från Arboga reningsverk. Detta inkluderade både simuleringar i Benchmark Simulation Model no. 2 (BSM2) samt studier genom vattenprovtagning vid Arboga reningsverk. Vid simuleringarna genomförda i BSM2 påvisades en märkbart lägre halt totalkväve i utgående avloppsvatten efter rejektvattenbehandlingens införande. Även vid den provtagningscykel som genomfördes på Arboga reningsverk under april år 2012 påvisades att markanta förändringar skett i utgående halter totalkväve och ammoniumkväve. Halterna totalkväve och ammoniumkväve i utgående avloppsvatten sjönk med ca 40 % respektive 65 % relativt samma tidsperiod år 2008–2011. Detta är dock endast resultat från det initiala skedet av rejektvattenbehandlingen som togs i drift 16 februari år 2012. Studien visade sammanfattningsvis att denna typ av processlösning för rejektvattenbehandling ledde till lägre halter av totalkväve och ammoniumkväve i utgående vatten från Arboga reningsverk. Dock krävs vidare studier för att kartläggaden slutgiltiga effekten av rejektvattenbehandlingen, då den i nuläget ännu ej nått sin slutgiltiga kapacitet. / Eutrophication problems were discovered in the Baltic Sea during the 1990s, why thesurrounding countries came to an agreement regarding measures to reduce the problem. Swedish wastewater treatment plants that influence the Baltic Sea by their emissions ofnitrogen and phosphorus have since introduced limit values for nitrogen and phosphorusconcentrations in the effluent water.At Arboga wastewater treatment plant (WWTP) a nitrogen reduction process withactive sludge was implemented a few years back. The recipient Arbogaån leading intoGalten, Mälaren, has eutrophication issues, and from the year 2012 the concentration oftotal nitrogen in treated wastewater must not exceed 15 mg tot-N/l. This limit resulted inmeasures to reduce nitrogen emissions.Reject water treatment is a common method to reduce the levels of total nitrogen intreated wastewater. Normally, the reject water contributes to 0.5–1.0 % of the totalinflow to the treatment plant but 10–20 % of the incoming total nitrogen load. In Arboga, the new limit for total nitrogen emissions resulted in a reject water treatmentfacility with predenitrification. The reject water is routed through four zones, twoanaerobic followed by two aerobic. Ammonium is by this process converted in to nitrogen gas via nitrate. This study aimed at identifying the effect from what implementing a reject watertreatment on the levels of total nitrogen in treated wastewater from Arboga WWTP.This included simulations in the Benchmark Simulation Model no. 2 (BSM2) as well aswater sampling at Arboga WWTP. The simulations that were carried out in BSM2 showed a significantly lower content of total nitrogen in treated wastewater after thereject water treatment was implemented. The sampling cycle conducted at ArbogaWWTP in April 2012 revealed that changes occurred in the levels of total nitrogen andammonium in the effluent water. The concentrations of total nitrogen and ammonia nitrogen in treated wastewater decreased by about 40 % and 65 %, compared to thesame time period in 2008–2011. This is, however, only results from the initial stage ofthe reject water treatment, which began operating on February 16th 2012.In summary, this study showed that this type of process solution for reject watertreatment resulted in lower levels of total nitrogen and ammonia in the effluent water at  Arboga WWTP. Further studies are needed to determine the final efficiency of the rejectwater treatment, since it yet has to reach its full capacity.

Microalgae are a diverse group of unicellular microorganisms found in various environments, ranging from small garden ponds to lakes with extreme salinity. Common for all microalgae is their ability to convert solar energy and carbon dioxide into chemical energy via photosynthesis. Additionally, they are capable of assimilating large amounts of nitrogen and phosphorus to produce proteins and lipids. These abilities have made microalgae an interesting candidate for next generation wastewater treatment coupled with production of biogas, a renewable energy source in advancement. At the Nykvarn wastewater treatment plant in Linköping, Sweden, 15,400,000 m3 of wastewater are treated annually to remove nitrogen and phosphorus that otherwise would risk to cause eutrophication in surrounding lakes and rivers. Moreover, the treatment plant manages large amounts of sewage sludge that is anaerobically digested to produce biogas and simultaneously reduce the sludge volumes. At the Nykvarn wastewater treatment plant, dewatering of the digested sludge results in a sludge fraction of about 30 % dry content and reject water, which is very nutrient-rich and therefore requires treatment in a SHARON process before it is reintroduced to the main stream of the wastewater treatment plant. In this thesis, the potential of microalgae for nutrient assimilation was studied by monitoring the nutrient removal efficiency of a mixed culture of microalgae when fed with 1) 100 % incoming wastewater, 2) 80 % incoming wastewater + 20 % reject water and 3) 60 % incoming wastewater + 40 % reject water. Furthermore, the effect of a process additive on the nutrient removal efficiency was evaluated. The results showed that microalgae are capable of removing 100 % of ingoing ammonium nitrogen and phosphate phosphorus when fed with incoming wastewater. At transition to 20 % and 40 % reject water, the culture was light-limited with a resulting ammonium reduction of 60 % and a phosphate reduction of around 30 %. The process additive slightly improved the ammonium reduction, however, mainly by formation of nitrite and nitrate by nitrifying bacteria. Moreover, a bio-methane potential test compared the methane potential of the microalgal biomass and the biomass from the SHARON process. The test resulted in an accumulated methane production around 70 mL g-1 VS-1 for the microalgal biomass and 35 mL g-1 VS-1 for the biomass from the SHARON process. That is, the mixed microalgal culture used in this experiment has a methane potential twice that of the biomass from the SHARON process. Finally, an economic analysis of a microalgae based process for purification of reject water showed that the operating costs exceed those of the SHARON process due to high energy consumption. It is thus necessary to choose a cultivation system that effectively utilize the solar energy, as well as maximize the biogas yield from anaerobic digestion of microalgal biomass.