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Design of Passive UHF RFID Tag Antennas and Industry ApplicationWu, Xunxun January 2010 (has links)
Nowadays, there is a growing demand for reliable assets security and management in various industries. The company SolarWave is eager to implement a comprehensive security system to produce active protection for their expensive product: solar panels. This security system is not only including assets tracking, monitoring but also combined with a control system, which is used to binary control a switch of solar panel to be on in presence of the correct ID and off in absence of the correct ID. One of the technologies that made this concept viable is known as Radio Frequency Identification (RFID). The thesis project is a sub-project in the development project whose content is mentioned as above. It contains two main parts. One is the system solution for the company. The other is RFID tag design which is in parallel with the company solution in order to reach a scientific level of a master thesis. In this thesis, I systematically analyze the operating mechanism and characteristics of RFID, and propose both active and passive RFID solutions for the company. And I also suggest an alternative radio technology ZigBee which can be used instead or as a complement to RFID. Meanwhile, I propose two designs of RFID tag according to the specification of the solar panel. One is modified meandering antenna. This kind of antenna is very effective and popular in RFID tag design in order to minimize the size of antenna. The other is inductively coupled loop antenna. It is a very useful method for conjugate matching in RFID tag antenna. The required input resistance and reactance can be achieved separately by choosing appropriate geometry parameters. It makes the antenna easier to match to the tag chips. Both the RFID antenna designs are simulated on Ansoft HFSS 12.
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The Mechanical Design and Analysis of an Active Prosthetic KneeLim, James January 2008 (has links)
In a world of war and turmoil in developing nations, land mines are becoming a concern, as millions of them are scattered in countries all over the world. Moreover, land mine prevention programs cannot clear land mine fields as fast as they are detonated each day. As a result, there are thousands that fall victim each year. There is immense demand for newer technologies to replace the aging prostheses used in these war torn nations. The active prosthetic knee (APK) design project is a novel design that utilizes simple, robust one degree of freedom (DOF) mechanics, while providing fully active knee torque control. The APK utilizes a high-speed brushed servomotor, providing the necessary torque and dynamics to provide the necessary gait characteristics of human locomotion. The main research contributions of this thesis are: 1) the mechanics and 2) the intelligence of the APK. This thesis investigates and highlights the prosthetic’s design process. The human biological system is studied and used as the design criteria when designing the device. Anthropometric data was used to determine the sizing and other physical properties. Moreover, Adaptive-Network-based Fuzzy-Interference Systems (ANFIS) and Fuzzy Interference Systems (FIS) are used to provide control to the APK. Finite element analysis (FEA) verifies the structural integrity of the APK. Four simulations are analyzed: equivalent stress, equivalent strain, shear stress and total deformation. These four simulations provide a mathematical interpretation of the physical system. We found that the first prototype, although a sound design, can be further improved to allow greater loading capabilities. Moreover, cyclical loading and total life cycles would also be significantly improved. A modular test stand is also designed and prototyped to allow APK testing. Since the APK prototype cannot be immediately placed on a human test subject, the test stand allows for experimentation in replicating human gait cycles.
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An Analysis of Stated and Revealed Preference Cycling Behaviour: A Case Study of the Regional Municipality of WaterlooRewa, Kyrylo Cyril January 2012 (has links)
Amongst transportation professionals there is a motivation to increase the use of active transportation to achieve contemporary transportation engineering goals. This research describes a year-long GPS cycling study conducted in partnership by the University of Waterloo and the Region of Waterloo Ontario. Data were collected from 415 self-selected cyclists, using two distinct data collection mechanisms. Data collected from GPS units revealed trip origins, destinations, and routes; the data also contain time stamps from which travel speeds can be computed. An online survey was administered to gather cyclists’ socio-economic information and household composition. The survey also collected responses to questions regarding preferences for cycling infrastructure and overall satisfaction.
The trip data allow for several important conclusions. The average trip length observed in the study was 6.96 kilometers; utilitarian trips (i.e. non-recreational) constitute 92% of the observed trips. This suggests that cyclists are able to complete daily activities – commuting, shopping, etc. – with less overall travel than the general population. The trip data also suggests relationships between the propensity to cycle and land use patterns. Strong positive correlations are demonstrated between higher land use density and the number of cycling trips; moreover, cycling trips tend to be more direct in areas with traditional neighbourhood design. The time at which the trips were taken – predominantly the am or pm peaks – suggest that the cyclists’ mode choice results in lowering peak demand and, therefore, reducing regional congestion. Fewer and typically shorter cycling trips were observed during winter months, presumably as a result of less favorable climate.
Participants in the study are typically higher-than-average earners and mirror the overall regional age distribution, although seniors and children were underrepresented. The cyclists in the study are predominantly male which may reflect an overall higher propensity to cycle amongst men compared to women. Cyclists’ households are more likely than the general population to own fewer cars than licensed drivers which may be interpreted as a cost saving opportunities for these households. Finally, the survey data suggests that the single largest impediment to increased cycling is a perception of poor safety for cyclists, particularly in terms of interactions with automobiles.
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A study of the solubilization of compounds of the types found in the resinous fraction of wood pulps.Wiseman, William Howard 01 January 1958 (has links)
No description available.
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Paleoseismicity in the Shihkang areaTang, Hou-Shu 29 September 2004 (has links)
none
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Synthesis and Reactivity Study of Tris(1-pyrazolyl)methane Copper(I) Complexes Relating to the Copper Protein Active Site Modeling ComplexesChang, Po-Chih 01 October 2004 (has links)
Nitrous oxide is a greenhouse gas produced in large quantity by several industrial processes. Efficient means of eliminating N2O are therefore of interest. The denitrification enzyme nitrous oxide reductase (N2OR), which reduces N2O to N2 and water , has recently been shown to contain an unprecedented [Cu4-µ4S] active site. Multinuclear copper sulfide compounds are known but have not been studied in the context of modeling N2OR or as N2O reduction catalysts. The synthesis of new tetranuclear [Cu4-µ4S] compounds is proposed to model the N2OR active site.The purpose of our research is to synthesize [Cu2-µ2S] complex, which original compound of [Cu4-µ4S] complex. This can be groundwork for mimicking the copper protein active site.
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The Composed Index of Mutual Fund And The Active Monitor of Fund PerformanceWang, Yu-jen 29 August 2005 (has links)
none
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Characterization of the nuclease of Vibrio vulnificusWu, Hui-Chi 22 June 2001 (has links)
The periplasmic nuclease of Vibrio vulnificus, Vvn, has been purified to homogeneity by a one step purification procedure using chromatography on a SP Sepharose column. The purified enzyme showed different mobilities on reducing and non-reducing SDS-PAGE, suggesting that disulfide bonds are involved in the maintenance of a stable tertiary conformation of the protein. Vvn randomly cleaved single and double stranded DNA and RNA, and possessed endonucleolytic activity. The enzyme exhibited an optimal activity between pH 8.0 and pH 10.0, and the optimal temperatures for the DNase and RNase activity were 40 oC ¡V 60 oC and 40 oC ¡V 50 oC, respectively. The enzymatic activity was inhibited by EDTA and EGTA, indicating that Vvn was a metalloenzyme. The DNase and RNase activity of Vvn had different requirements for divalent cations. Chemical modification studies on Vvn revealed the involvement of lysine, arginine, tryptophan and carboxylate residues in the catalytic activity of the enzyme. The extents of inactivation of the DNase and RNase activity of Vvn by modification of the carboxylate group with EDC were different. Substrate DNA and RNA protected the DNase and RNase activity of Vvn from inactivation by PLP, PGO, NBS and EDC which modified lysine, arginine, tryptophan and the carboxylate group. Mg2+ could not protect the DNase and RNase activity of Vvn against the inactivation by PLP and PGO. Whereas Mg2+ protection was observed in NBS- and EDC-mediated inactivation of the DNase but not the RNase activity of Vvn . From these results, it is postulate that there may be two distinct but overlapping active sites, for the DNase and RNase activity, respectively.
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Active control of underwater propulsor using shape memory alloysWasylyszyn, Jonathan Allen 25 April 2007 (has links)
The development of a leading edge propeller blade reconfiguration system using Shape Memory Allow (SMA) muscles is presented. This work describes the design and testing of a leading edge flap, which is used to alter the local camber of a propeller blade. The leading edge flap is deflected by SMA wires housed in the blade and maintained in a fixed position with a shaft locking and releasing mechanism. A locking and releasing mechanism is utilized so that constant actuation of the SMAs is not required to maintain leading edge deflection. The profile at 70% span of the propeller blade was used to create a two-dimensional blade for leading edge flap design implementation and load testing. Deflection of up to five degrees was obtained with the final design of the leading edge flap and locking and releasing mechanism. The SMA muscles used to deflect the leading edge were actuated electronically through resistive heating and were controlled by a proportional/integral gain control algorithm with closed-loop feedback from a linear displacement sensor within the blade. With the final design of the leading edge flap and locking and releasing mechanism, a preliminary design for a three-dimensional propeller was created.
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Frequency Shaped LQR Design of an Active Noise Cancellation HeadphoneLin, Tsai-Fu 26 August 2009 (has links)
The purpose of this thesis is to design and implement an active noise cancellation headphone (ANC) with a feedback controller optimally designed using the linear quadratic regulator (LQR) design approach. The controller compares the audio input signal with the measured signal from a mini microphone in the headphone, and attempts to generate a control signal so that the headphone may reproduce a clean, low noise audio sound, without being interfered by the environmental noise.
The control bandwidth of the ANC headphone is 100~600Hz. The controller design emphasizes the choice of a weighting function in shaping the controller gain at different frequencies, so as to achieve maximum in-band noise cancellation and low noise amplification outside the bandwidth. The experimental result shows achievable noise cancellation of maximum 25dB within the control bandwidth and a barely noticeable slight noise amplification of maximum 6dB at high frequencies and 4.5dB at inaudible low frequencies.
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