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Sustainable utilisation of raw sewage sludge (RSS) as a water replacement in cement-based materials containing unprocessed fly ashHamood, Alaa January 2014 (has links)
Prior to the implementation of the European Union Urban Waste Water Treatment Directive (91/271/EEC) in 31 Dec 1998, around a quarter of the sewage sludge produced in the UK was either discharged to surface waters via pipes or disposed from ships at sea. Discontinuing this route together with the quality requirements of the European Waste Water Directive, led to the generation of significant quantities of sewage sludge. It has therefore become required to treat this waste effectively before it can be sent back to the environment. Consequently, this added greater challenges for the environmental agencies, as well as local authorities. The treatment process comprises costly and energy consuming applications including physical, chemical, biological and thermal. In addition to the sewage sludge, the power generation industry produces massive quantities of fly ash from burning coal. In the UK, there is about 5,300,000 tonnes of fly ash that are generated annually, which require to be processed and classified in order to meet the standard requirements before it can be used in the construction applications. The classifying process also involves a series of costly and energy consuming mechanical and physical applications. This research programme has introduced an innovative alternative to the traditional re-use and disposal routes of Raw Sewage Sludge (RSS) and unprocessed fly ash. It has suggested the utilisation of RSS and unprocessed fly ash as raw ingredients for the production of sustainable construction materials. This research programme has therefore examined the performance of cement-based materials containing Raw Sewage Sludge (RSS) as a water replacement and unprocessed fly ash as cement replacement. Mortar and concrete mixes incorporating these materials were tested for their flowability/workability, density, Total Water Absorption (TWA), Ultrasonic Pulse Velocity (UPV), compressive strength, flexural strength, drying shrinkage, sulphate attack and leaching properties. Three series of cement-based materials were studied including mortar mixes with RSS and unprocessed fly ash (Series 1), mortar mixes with RSS and large proportions of unprocessed fly ash (Series 2), and concrete mixes with RSS and unprocessed fly ash (Series 3). The outcomes of the investigation were encouraging in that cement-based materials containing RSS and unprocessed fly ash that were produced demonstrated relatively good engineering, durability and environmental properties in comparison to the control mixes. The inclusion of unprocessed fly ash significantly reduced flowability/workability; however it improved long-term compressive strength for both mixes with RSS and water. The best compressive strength results were recorded when cement was replaced with 10-20% unprocessed fly ash by weight of total binder. The results also showed that sulphate attack resistance improved when fly ash was included. Moreover, safe concentration levels of heavy metals and free ions were detected when leaching test was performed. However, it must be kept in mind that more environmental tests must be performed before any large scale use is undertaken.
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Bounds on RF cooperative localization for video capsule endoscopyYe, Yunxing 29 April 2013 (has links)
Wireless video capsule endoscopy has been in use for over a decade and it uses radio frequency (RF) signals to transmit approximately fifty five thousands clear pictures of inside the GI tract to the body-mounted sensor array. However, physician has no clue on the exact location of the capsule inside the GI tract to associate it with the pictures showing abnormalities such as bleeding or tumors. It is desirable to use the same RF signal for localization of the VCE as it passes through the human GI tract. In this thesis, we address the accuracy limits of RF localization techniques for VCE localization applications. We present an assessment of the accuracy of cooperative localization of VCE using radio frequency (RF) signals with particular emphasis on localization inside the small intestine. We derive the Cramer-Rao Lower Bound (CRLB) for cooperative location estimators using the received signal strength(RSS) or the time of arrival (TOA) of the RF signal. Our derivations are based on a three-dimension human body model, an existing model for RSS propagation from implant organs to body surface and a TOA ranging error model for the effects of non-homogenity of the human body on TOA of the RF signals. Using models for RSS and TOA errors, we first calculate the 3D CRLB bounds for cooperative localization of the VCE in three major digestive organs in the path of GI tract: the stomach, the small intestine and the large intestine. Then we analyze the performance of localization techniques on a typical path inside the small intestine. Our analysis includes the effects of number of external sensors, the external sensor array topology, number of VCE in cooperation and the random variations in transmit power from the capsule.
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A Real-Time Laboratory Testbed For Evaluating Localization Performance Of WIFI RFID TechnologiesAssad, Muhammad Ali 04 May 2007 (has links)
A realistic comparative performance evaluation of indoor Geolocation systems is a complex and challenging problem facing the research community. This is due to the fact that performance of these systems depends on the statistical variations of the fading multipath characteristics of the wireless channel, the density and distribution of the access points in the area, and the number of the training points used by the positioning algorithm. This problem, in particular, becomes more challenging when we address RFID devices, because the RFID tags and the positioning algorithm are implemented in two separate devices. In this thesis, we have designed and implemented a testbed for comparative performance evaluation of RFID localization systems in a controlled and repeatable laboratory environment. The testbed consists of a real-time RF channel simulator, several WiFi 802.11 access points, commercial RFID tags, and a laptop loaded with the positioning algorithm and its associated user interface. In the real-time channel simulator the fading multipath characteristics of the wireless channel between the access points and the RFID tags is modeled by a modified site-specific IEEE 802.11 channel model which combines this model with the correlation model of shadow fading existing in the literature. The testbed is first used to compare the performance of the modified IEEE 802.11 channel model and the Ray Tracing channel model previously reported in the literature. Then, the testbed with the new channel model is used for comparative performance evaluation of two different WiFi RFID devices.
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A Comparison between Vector Algorithm and CRSS Algorithms for Indoor Localization using Received Signal StrengthObeidat, Huthaifa A.N., Dama, Yousef A.S., Abd-Alhameed, Raed A., Hu, Yim Fun, Qahwaji, Rami S.R., Noras, James M., Jones, Steven M.R. 03 1900 (has links)
no / A comparison is presented between two indoor localization algorithms using received signal strength, namely the vector algorithm and the Comparative Received Signal Strength (CRSS) algorithm. Signal values were obtained using ray tracing software and processed with MATLAB to ascertain the effects on localization accuracy of radio map resolution, number of access points and operating frequency. The vector algorithm outperforms the CRSS algorithm, which suffers from ambiguity, although that can be reduced by using more access points and a higher operating frequency. Ambiguity is worsened by the addition of more reference points. The vector algorithm performance is enhanced by adding more access points and reference points while it degrades with increasing frequency provided that the statistical mean of error increased to about 60 cm for most studied cases. / Unable to contact publisher. Contact webform only works for members - no email addresses. Raed said he would try and get contact details - email 14th March 2016 / The full text is unavailable. The publisher is unable to be contacted.
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RSS Feeds, Browsing and End-User EngagementWest, Mary Beth 01 April 2011 (has links)
Despite the vast amount of research that has been devoted separately to the topics of browsing and Really Simple Syndication (RSS) aggregation architecture, little is known about how end-users engage with RSS feeds and how they browse while using a feed aggregate. This study explores the browsing behaviors end-users exhibit when using RSS and Atom feeds. The researcher analyzed end-users’ browsing experiences and discusses browsing variations. The researcher observed, tested, and interviewed eighteen (N=18) undergraduate students at the University of Tennessee to determine how end-users engage with RSS feeds.
This study evaluates browsing using two variations of tasks, (1) an implicit task with no final goal and (2) an explicit task with a final goal. The researcher observed the participants complete the two tasks and conducted exit interviews, which addressed the end-users’ experiences with Google Reader and provided further explanation of browsing behaviors. The researcher analyzed the browsing behaviors based upon Bates’ (2007) definitions and characteristics of browsing. The results of this exploratory research provide insights into end-user interaction with RSS feeds.
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The Role of Epigenetics in Regulating V(D)J Recombination and Allelic ExclusionKondilis-Mangum, Hrisavgi Demetrios January 2011 (has links)
<p>As members of the adaptive immune response, T- and B- cells express unique antigen receptors generated from antigen receptor loci. These loci encode multiple Variable (V), Diversity (D), and Joining (J) gene segments. Through a process known as V(D)J recombination, genomic rearrangements occur to generate a unique antigen receptor proteins. During each stage of lymphocyte development, antigen receptor loci are epigenetically regulated. The epigenetic regulation promotes and inhibits V(D)J recombination through different mechanisms. To generate an antigen receptor protein, the substrates for rearrangement (recombination signal sequences, RSSs) must be made accessible to the recombination machinery. Moreover, once an antigen receptor locus has rearranged and produced a successful in-frame protein, a mechanism known as allelic exclusion prevents further recombination.</p><p>The nucleosome can positively and negatively regulate V(D)J recombination. Therefore, we defined the in vivo nucleosome organization of accessible and inaccessible RSSs on the Tcr loci. We used Tcrb and Tcra alleles which lack various cis-elements (e.g. enhancers and promoters) and terminate transcription. By comparing nucleosome organization and histone octamer occupancy, we found that accessible alleles are characterized by lower histone octamer occupancy and in some cases movement of nucleosomes. Also, we found that some these changes are mediated by transcription through the RSS. We concluded that one mechanism by which cis-elements epigenetically regulate RSS accessibility is by histone octamer loss and nucleosome repositioning and that some of these changes are mediated by transcription.</p><p>In addition, we further investigated how allelic exclusion prevents Tcrb locus recombination in CD4, CD8 double positive (DP) thymocytes. A previous study had introduced the Tcra enhancer (Eα) into the middle of the Tcrb locus to test if allelic exclusion was mediated solely by RSS accessibility. That study found that Eα could force RSS accessibility in DP thymocytes, but Vβ RSS accessibility did not overcome additional mechanisms involved in allelic exclusion. One potential mechanism that has been suggested in the literature is changes in locus conformation. Thus, we tested if RSS accessibility and locus conformation together mediate allelic exclusion. We generated two alleles that overcome changes in RSS accessibility, due to the presence of Eα and that overcome changes in locus conformation, due to a decrease in distance between Vβ and DJβ RSSs. We found that both alleles are accessible in DP thymocytes and we detected Vβ to DJβ recombination in DP thymocytes. Therefore, the epigenetic mechanisms that regulate Tcrb allelic exclusion consists of changes in RSS accessibility and changes in locus conformation.</p> / Dissertation
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RSS-based WLAN Indoor Positioning and Tracking System Using Compressive Sensing and Its Implementation on Mobile DevicesAu, Anthea Wain Sy 14 December 2010 (has links)
As the demand of indoor Location-Based Services (LBSs) increases, there is a growing interest in developing an accurate indoor positioning and tracking system on mobile devices. The core location determination problem can be reformulated as a sparse natured problem and thus can be solved by applying the Compressive Sensing (CS) theory. This thesis proposes a compact received signal strength (RSS) based real-time indoor positioning and tracking systems using CS theory that can be implemented on personal digital assistants (PDAs) and smartphones, which are both limited in processing power and memory compared to laptops. The proposed tracking system, together with a simple navigation module is implemented on Windows Mobile-operated smart devices and their performance in different experimental sites are evaluated. Experimental results show that the proposed system is a lightweight real-time algorithm that performs better than other traditional fingerprinting methods in terms of accuracy under constraints of limited processing and memory resources.
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RSS-based WLAN Indoor Positioning and Tracking System Using Compressive Sensing and Its Implementation on Mobile DevicesAu, Anthea Wain Sy 14 December 2010 (has links)
As the demand of indoor Location-Based Services (LBSs) increases, there is a growing interest in developing an accurate indoor positioning and tracking system on mobile devices. The core location determination problem can be reformulated as a sparse natured problem and thus can be solved by applying the Compressive Sensing (CS) theory. This thesis proposes a compact received signal strength (RSS) based real-time indoor positioning and tracking systems using CS theory that can be implemented on personal digital assistants (PDAs) and smartphones, which are both limited in processing power and memory compared to laptops. The proposed tracking system, together with a simple navigation module is implemented on Windows Mobile-operated smart devices and their performance in different experimental sites are evaluated. Experimental results show that the proposed system is a lightweight real-time algorithm that performs better than other traditional fingerprinting methods in terms of accuracy under constraints of limited processing and memory resources.
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Indoor and Outdoor Evaluation of Campus RSS PerformanceLi, Qian, Zhang, Xintong January 2011 (has links)
The focus of this thesis work is to evaluate the RSS (Received Signal Strength) Performance of the University of Gävle (HiG) based on IEEE 802.11 standards both indoor and outdoor. Authors investigated the issues of deploying access points for wireless local area networks in the library-2nd floor, building 99-4th floor and outdoor university campus. By using the program VisiWave Site Survey, Global Position System (GPS) and RSS sensor to analysis the received signal strength, throughput and radio map. The influence of the building material and distance for the signal strength and the throughput are done by investigating indoor environment. The results of investigation suggest that most parts of library-2nd floor and building 99-4th floor possess at least a good RSS performance. However, minority parts of these places have a poor RSS performance, and the new resolution of Access Points’ (AP) deployment for these poor-RSS-performance parts is provided. For the outdoor campus part, the RSS in the area which near the walls of building is satisfactory (Received Signal Strength Indication (RSSI) between -79.8 dBm and -57 dBm), however in the centre of outdoor campus the RSS is poor. Thus, the evaluation of APs deployment in HiG is achieved.
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Potential of existing UMTS Signaling Data for Cell Phone PositioningAkram, Awais, Ahmad, Hamad January 2011 (has links)
In the current era of telecommunication the usage of cellular network has increased rapidly. Number of different new services are introduced i.e. navigation, friend finder, internet browsing, nearby filling stations, shopping centers, traffic information and emergency services. Most of these services are location based and needs the information of particular area to provide the exact services. The addition of location based services in 3G network opens the new ways of using Mobile devices due to which cellular networks has faced number of challenges in providing better positioning accuracy which is the main requirement for location based services. To bear these challenges everyday new ways of finding the accurate position are introduced but most them required upgraded networks or highly equipped terminal. In this thesis the purpose is to find the potential in UMTS signaling data to estimate the position of the user equipment as accurate as possible using the legacy terminals. In this thesis SFN-SFN observed time difference is explored and used in Database Correlation Method (DCM) in network based positioning. This thesis is done by first analyzing the RSCP for the particular area to verify the conditions of FCC. The data is collected in real environment through test drive using TEMS investigation tool and the available measurement reports from the terminal are used to design and implement the DCM Algorithm. Two new approaches are introduced in this thesis SFN-SFN OTD and Hybrid. In Hybrid RSCP and SFN-SFN OTD are used together. In conclusion, the final results from the performed experiments show improvement in estimated position accuracy by Hybrid technique which is a new step in finding the position of user equipment by DCM.
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