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Rowehl, Jill A. (Jill Annette). "Organic multilayer photoconductor utilizing a spacer layer." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/57977.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 61-62).<br>Chemosensors hold many vital applications in today's world, particularly as detectors for explosives. There is still vast room for improvement as other technologies-particularly those of explosives-continue to evolve and expand. Herein, we develop a novel device structure with the potential for much higher sensitivity. The lateral bilayer photoconductor is comprised of an exciton generation layer (EGL) and a charge transport layer (CTL). This separates the functionality of chemical sensing from the charge transport, allowing each film to be independently optimized. As a further improvement on this structure, we introduce a spacer layer to separate charge carriers in the EGL and the CTL, reducing bimolecular recombination at the interface. As a proof of concept, we fabricate and characterize lateral multilayer photoconductors composed of small molecule organic films. It is experimentally demonstrated that the utilization of a spacer layer can produce an order of magnitude enhancement in quantum efficiency over the of a spacer layer can produce an order of magnitude enhancement in quantum efficiency over the The work reported here provides encouraging results in the fields of chemosensors and organic optoelectronics.<br>by Jill A. Rowehl.<br>S.B.
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Wang, Yuekun. "In0.53Ga0.47As-In0.52Al0.48As multiple quantum well THz photoconductive switches and In0.53Ga0.47As-AlAs asymmetric spacer layer tunnel (ASPAT) diodes for THz electronics." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/in053ga047asin052al048as-multiple-quantum-well-thz-photoconductive-switches-and-in053ga047asalas-asymmetric-spacer-layer-tunnel-aspat-diodes-for-thz-electronics(5fd73bd5-aef3-476b-be1b-7498da3f9627).html.
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This thesis is concerned with terahertz (THz) technology from both optical and electronic approaches. On the optical front, the investigation of optimised photoconductive switches included the characterisation, fabrication and testing of devices which can generate and detect THz radiation over the frequency range from DC to ~ 2.5 THz. These devices incorporated semiconductor photoconductors grown under low temperature (LT) Molecular Beam Epitaxy (MBE) conditions and using distributed Bragg reflectors (DBRs). The material properties were studied via numerous characterisation techniques which included Hall Effect and mid infrared reflections. Antenna structures were fabricated on the surface of the active layers and pulsed/continuous wave (CW) signal absorbed by these structures (under bias) generates photocurrent. With the help of the DBRs at certain wavelengths (800 nm and 1550 nm), the absorption coefficient at the corresponding illumination wavelength increased thus leading to significant increase of the THz output power while the materials kept the desirable photoconductive material properties such as high dark resistivity and high electron mobility. The inclusion of DBRs resulted in more than doubling of the THz peak signals across the entire operating frequency range and significant improvements in the relative THz power. For the THz electronic approach, a new type of InP-based Asymmetric Spacer Tunnel Diode (ASPAT), which can be used for high frequency detector, was studied. The asymmetric DC characteristics for this novel tunnel diode showed direct compatibility with high frequency zero-bias detector applications. The devices also showed an extreme thermal stability (less than 7.8% current change from 77 K to 400 K) as the main carrier transport mechanism of the ASPAT was tunnelling. Physical models for this ASPAT diode were developed for both DC (direct current) and AC (alternating current) simulations using the TCAD software tool SILVACO. The simulated DC results showed almost perfect matches with measurements across the entire temperature range from 77 K to 400 K. From RF (radio frequency) measurements, the intrinsic diode parameters were extracted and compared with measured data. The simulated zero biased detector circuits operating at 100 GHz and 240 GHz using the new InGaAs-AlAs ASPAT diode (4*4 micrometer square) showed comparable voltage sensitivities to state of the art Schottky barrier diodes (SBDs) detectors but with the added advantage of excellent thermal stability.
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González, Gaarslev Natalia. "Growth and biodegradation by Sporidiobolales yeasts in vanillin-supplemented medium." Thesis, Högskolan i Gävle, Avdelningen för arbets- och folkhälsovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-24678.
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Studies of biodegradation in lignins by basidiomycetes yeasts show the conversion of lignin in various degradation products among which vanillin, a valuable substance, suggested to be a strong inhibitor of both fermentation and growth of yeasts, stands. Sporidiobolales yeasts used in these experiments were aimed to be identified by their highly conserved ITS region as well as studied in vanillinsupplemented medium through, vanillin-supplemented plates, TLC and Neubauer’s chamber to find out which, among the several isolates tested, were the most resistant ones, understand how they take up vanillin and how their growth is affected by the presence of the phenolic compound. Two strains were identified as Rhodotorula babjevae. One of them, L4, together with LS22, Rhodosporidium kratochvilovae, could withstand and biodegrade high concentrations of vanillin, producing biodegradation products with Rf values similar to the ones know for vanillic acid and vanillyl alcohol. Better growth in medium supplemented with small doses of vanillin was found, as well as disparity among the same species and their metabolic features, therefore, herbicides resistance was suggested as a reason for strains divergence. Further morphological-species comparison could also describe if there exist a relation between them.<br>Estudios sobre la biodegradación de ligninas por levaduras basidiomicetes muestran la conversión de lignina en distintos productos de degradación, entre los cuales se encuentra la vainillina, un fuerte inhibidor de la fermentación y el crecimiento de levaduras. Las levaduras Sporidiobolales utilizadas en estos experimentos han intentado ser identificadas a través de la región ETI, muy conservada, además de estudiadas en medios suplementados con vainillina mediante placas suplementadas con vainillina, CCF y cámara de Neubauer para averiguar cuáles son las cepas más resistentes, entender cómo metabolizan la vainillina y cómo su crecimiento se ve afectado por la presencia de dicho compuesto. Dos cepas fueron identificadas como Rhodotorula babjevae. Una de ellas, L4, junto con con la cepa LS22, Rhodosporidium kratochvilovae, pudieron soportar y biodegradar elevadas concentraciones de vainillina, originando productos de biodegradación con valores de Rf similares a los del ácido vanílico y alcohol vanílico previamente conocidos. Se encontró un crecimiento mejor en medios suplementados con pequeñas dosis de vainillina además de una disparidad entre mismas especies y sus características metabólicas, así, herbicidas han sido sugeridos como una posible causa en dicha divergencia. Una futura comparación morfología-especie podrá describir si existe relación entre ambos.
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Conrad, Ross Aaron. "Impact of the boundary layer on pointing and tracking in airborne free-space laser communication links." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44929.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2008.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes vita.<br>Includes bibliographical references (p. 117-118).<br>Free-space laser communication is a developing technology with enormous potential to revolutionize the way people communicate across the globe. Of specific interest are air-to-space lasercom links. Such a link experiences atmospheric scintillation, platform jitter, and boundary layer turbulence. This research investigated the tracking challenge using a focal plane array sensor with centroid and peak tracking algorithms. Also investigated was the use of a deformable mirror to recreate optical phase distortions from boundary layer turbulence. Experiments were conducted with realistic channel effects for multiple look angles between a subsonic aircraft at 29 kft and geosynchronous satellite. Performance was determined by power delivered to an optical fiber. The results show that the two tracking algorithms can differ by up to one decibel of fiber power, with centroid tracking generally performing best. Conclusions are highly dependent on aircraft and spacecraft parameters but point towards centroid tracking for maximizing received power. Keywords: Lasercom, FPA Tracking, Boundary Layer Disturbances, Deformable Mirror.<br>by Ross Aaron Conrad.<br>S.M.
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Abdullah, Mohd. "GaAs/AlAs ASPAT diodes for millimetre and sub-millimetre wave applications." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/gaasalas-aspat-diodes-for-millimetre-and-submillimetre-wave-applications(89581b9e-edc9-4eb6-9392-e466a0f8de81).html.
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The Asymmetric Spacer layer Tunnel (ASPAT) diode is a new diode invented in the early 90s as an alternative to the Schottky barrier diode (SBD) technology for microwave detector applications due to its highly stable temperature characteristics. The ASPAT features a strong non-linear I-V characteristic as a result of tunnelling through a thin barrier, which enables RF detection at zero bias from microwaves up to submillimetre wave frequencies. In this work, two heavily doped GaAs contact layer on top and bottom layers adjacent to lightly doped GaAs intermediate layers, enclose undoped GaAs spacers with different lengths sandwiching an undoped AlAs layer that acts as a tunnel barrier. The ultimate ambition of this work was to develop a MMIC detector as well as a frequency source based on optimized ASPAT diodes for millimetre wave (100GHz) applications. The effect of material parameter and dimensions on the ASPAT source performances was described using an empirical model for the first time. Since this is a new device, keys challenges in this work were to improve DC and RF characteristic as well as to develop a repeatable, reproducible, and ultimately manufacturable fabrication process flow. This was investigated using two approaches namely air-bridge and dielectric-bridge fabrication process flows. Through this work, it was found that the GaAs/AlAs heterostructures ASPAT diode are more amenable to the dielectric-bridge technique as large-scale fabrication of mesa area up to 4Ã4Âμm2 with device yields exceeding 80% routinely produced. The fabrication of the ASPAT using i-line optical lithography which has the capability to reduce emitter area to 4Ã4Âμm2 to lower down the device capacitance for millimetre wave application has been made feasible in this work. The former challenge was extensively studied through materials and structural characterisations by a SILVACO physical modelling and confirmed by comparison with experimental data. The I-V characteristic of the fabricated ASPAT demonstrated outstanding scalability, demonstrating robust processing. A fair comparison has been made between ASPAT and SBD fabricated in-house; indicating ASPAT is extremely stable to the temperature. The RF characterisations were carried out with the aid of Keysight ADS software. The DC characteristic from fabricated GaAs/AlAs ASPAT diodes were absorbed into an ADS simulation tool and utilized to demonstrate the performance of MMIC 100GHz detector as well as 20GHz/40GHz signal generators. Zero bias ASPAT with mesa area of 4Ã4Âμm2 with video resistance of 90KΩ, junction capacitance of 23fF and curvature coefficient of 23V-1 has demonstrated detector voltage sensitivity above 2000V/W, while the signal source conversion loss and conversion efficiency are 28dB and 0.3% respectively. An estimate noise equivalent power (NEP) for this particular device is 18.8pW/Hz1/2.
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Affan, Amer. "Collapse of double-layer space grid structures." Thesis, University of Cambridge, 1987. https://www.repository.cam.ac.uk/handle/1810/250905.
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This dissertation is concerned with the behaviour of square-on-square double-layer space grids (DLSG's) and in particular their collapse mechanisms after initial buckling. A detailed review of the methods used for collapse analysis of these structures is conducted, which shows that their collapse can be of progressive nature. An outline of the remedies that have been suggested to make safe their collapse behaviour is given, and it traces the line for further study. The present investigation starts by describing the redundancy in these regular pin-jointed assemblies in terms of unit states of self-stress. This enables us to understand, by means of the extended Maxwell rule, how it is that mechanisms of collapse can occur when relatively few bars in the assembly have failed. The influence of boundary conditions on the mechanisms of collapse and its progressive nature is also investigated. This method of analysis is verified by detailed examination of several previously reported experimental results, and some conclusions can be drawn. The prestressing of statically indeterminate assemblies by means of lack-of-fit is investigated in the hope of changing their collapse characteristics. The unit state of self-stress has been used to explain a method for selecting the bars that can be shortened/lengthened in order to impose a prescribed state of self-stress, and the scope for achievable patterns of bar tensions has been described. A by-product of the investigation is an algorithm which calculates the required lack-of-fit to impose an initial state of self-stress which maximizes the load-carrying capacity of indeterminate trusses. Using the formulae derived for prestress, a statistical analysis is developed to estimate initial bar tensions due to random lack-of-fit in order to obtain a realistic estimate of the load-factor of an assembly before initial bar failure. Furthermore, we have argued and demonstrated how backlash at the bar-joint connection may have a beneficial effect in reducing substantially initial bar tensions due to the inevitable lack-of-fit on account of manufacturing errors of bars. An extensive experimental program has been conducted to verify the assumptions adopted and formulae derived in this dissertation.
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Sahol, Hamid Yazmin. "Progressive collapse of double layer space trusses." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/808321/.
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This study deals with the progressive collapse of full scale square-on-square double-layer space truss (DLST) systems. The failure of certain space structures in recent years, ranging from a lattice dome in Romania, Burcharest 1963 to the DLST in Hartford USA, 1978 and the recent collapse of the Sultan Zainal Abidin Stadium, a double-layer space frame constructed in Malaysia, 2009, gives an insight into how sensitive some space structures are to progressive collapse. These tragic incidents have provided very valuable lessons for designers of the importance of understanding progressive collapse in these structural configurations. By understanding what caused such failures engineers may avoid any reoccurrence and in addition help to develop safer structures. Hence, a study of this particular problem has been conducted and the results obtained are presented in the thesis. Evaluation on the consequences of progressive collapse leads to the determination of structural Vulnerability Index due to sudden loss of an individual member (Case 1) or losses of members progressively (Case 2). In order to trace the collapse behavior a nonlinear analysis subject to increasing applied load was used. However, it is difficult for engineers to perform this nonlinear analysis due to its complexity. Hence, a simple linear analysis as an alternative method was used whereby assessment of Vulnerability Index using linear analysis is carried out using two different approaches, i.e. Rate Factor and Probabilistic Approach. Since a DLST has large number of members which correspond to a large data set, hence, these two proposed approaches are suitable. A close statistical correlation between both approaches indicates that there is a high correlation between both approaches. To ensure reliability of the proposed approaches, their results are compared using nonlinear collapse analysis and the results are found to be in good agreement. The solution strategy used to analyse the full scale models was first tested using small scale models. The numerical results of the small scale models have been verified with pre-existing experimental results and good agreements between the results are obtained. Behavior of each DLST member and also the overall structural behavior can be obtained from the nonlinear analysis. There are three different boundary conditions of the DLSTs considered. Vulnerability of the DLSTs susceptible to progressive collapse are identified and then are compared for the identification of efficient structures. The Vulnerability Index of the DLST helps engineers to discover failures that may occur due to damage or loss of its members.
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Klochko, S. "The Laser Interferometer Space Antenna." Thesis, Сумський державний університет, 2012. http://essuir.sumdu.edu.ua/handle/123456789/28700.
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Terragni, Jacopo. "Laser Ablation for Space Applications." Doctoral thesis, Università degli studi di Trento, 2022. https://hdl.handle.net/11572/339556.
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Hone, David M. "Time and space resolution and mixed layer model accuracy." Monterey, California. Naval Postgraduate School, 1997. http://hdl.handle.net/10945/9080.
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The oceanic turbulent boundary layer is a critical region to understand for oceanic and atmospheric prediction. This thesis answers two fundamental questions: (1) what is the response of the ocean mixed layer system to transient forcing at the air sea surface? (2) what is the necessary time and space resolution in an ocean mixed layer model to resolve important transient responses? Beginning with replication of de Szoeke and Rhines' work, additional physical processes were added to include more realistic viscous dissipation and anisotropy in the three-dimensional turbulent kinetic energy (TKE) budget. These refinements resulted in modification of de Szoeke and Rhines' findings. Firstly, TKE unsteadiness is important for a minimum of 10 to the 5th power seconds. Secondly, viscous dissipation should not be approximated as simply proportional to shear production. Thirdly, entrainment shear production remains significant for a minimum of one pendulum-day. The required temporal model resolution is dependent on the phenomena to be studied. This study focused on the diurnal, synoptic, and annual cycles, which the one-hour time step of the Naval Postgraduate School model adequately resolves. The study of spatial resolution showed unexpectedly that model skill was comparable for 1 m, 10 m and even 20 m vertical grid spacing
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Parise, Ron, Keith Hogie, Ed Criscuolo, Rick Schnurr, John Wesdock, and Mark Burns. "A STANDARD LINK-LAYER PROTOCOL FOR SPACE MISSION COMMUNICATIONS." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/606387.
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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California<br>A necessary step for using Internet Protocols in space is to establish the basic link-layer framing
protocol for delivering Internet datagrams over satellite RF links. This paper discusses the low-level
data link issues related to using the ISO standard High-level Data Link Control (HDLC) protocol to
support spacecraft communications. A major driver for using HDLC is its very wide usage in the
Internet today and the large amount of commercially available network equipment and test equipment.
The results of a high-fidelity link simulation using HDLC are presented along with results of tests
performed in 2000-2001 using Internet protocols over HDLC on the UoSAT-12 spacecraft. A rationale
is provided for the selection of HDLC/Frame-Relay framing along with the IETF multi-protocol
encapsulation. It also discusses the historical usage of HDLC on over 70 satellite missions.
The paper also describes how HDLC relates to various applications of forward-error-correction (FEC)
coding techniques, such as convolutional coding and Reed-Solomon. It describes approaches for using
these techniques in ways that are independent of the protocols used at the data link layer and above. It
covers issues primarily related to layer 2 (Data Link) and its relationship to layer 1 (Physical). It does
not cover layer 3 (Network) and above.
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Farsangi, Hossein E. "Topological optimisation of double layer grids using genetic algorithm." Thesis, University of Surrey, 2002. http://epubs.surrey.ac.uk/750/.
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Hori, T., K. Kaneko, T. Mizutani, and M. Ishioka. "Space charge distribution in low-density polyethylene with blocking layer." IEEE, 2003. http://hdl.handle.net/2237/7165.
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Barlow, Janet F. "Turbulent transport of space charge in the atmospheric surface layer." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270265.
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Abu, Almaalie Zina. "Free space optical wireless communication with physical layer network coding." Thesis, Northumbria University, 2016. http://nrl.northumbria.ac.uk/32546/.
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Terrestrial free-space optical (FSO) communications is an emerging low-cost, licensefree and high-bandwidth access solution for a number of applications including the “last mile” access network. However, for a transmission range from a few meter to longer than 1 km, a number of atmospheric phenomena, such as rain, haze, fog, snow, scintillation and pointing errors become a major performance limiting factors in FSO systems resulting in link deterioration and ultimately complete link failure. Relay-assisted technique is capable of mitigating the signal fading and maintain acceptable performance levels. In this thesis, a two-way relay (TWR) channel technique is adopted to increase system spectral efficiency, which in turn boosts the network throughput. This is achieved by using a physical layer network coding (PNC) technique, where network coding (NC) is applied at the physical layer. It takes advantage of the superimposition of the electromagnetic waves, and embraces the interference, which was typically deemed as harmful, by performing the exclusive-OR mapping of both users’ information at the relay. Therefore, the main contribution of this thesis is to study the design of the TWR-FSO communication system that embraces PNC technique for the full utilization of network resources based on the binary phase shift keying (BPSK) modulation. Moreover, error control coding (ECC) in conjunction with interleaving can be employed in FSO communications to combat turbulence-induced fading, which can enhance the performance of the proposed TWR-FSO PNC system. A comparative study between convolutional code (CC) and bit-interleave coded modulation with iterative decoding (BICM-ID) code are carried out. The result shows that the BICM-ID code outperforms the CC for TWR-FSO based PNC over strong turbulence regime by ~10dB of SNR to achieve a BER of 10-4 . However, the number of users that can be simultaneously transmitted to the relay is considered the main constraint in PNC system. Therefore, to overcome this challenge, a new scheme that integrates the iterative multiuser detection (I-MUD) technique with the PNC system over RF and FSO links are introduced as another achievement. The results show that the I-MUD offers improved performance about 8, and 22dB of SNR to get a BER of 10-4 over RF and FSO channels, respectively, for number of simultaneously users equal to 14 with respect to TWR-PNC system.
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Nappier, Jennifer M. "An FPGA Abstraction Layer for the Space Telecommunications Radio System." Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1227033556.
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Brunzell, Martin. "Free-Space Dark Pulse Mode-Locked Laser." Thesis, KTH, Tillämpad fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296524.
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While the development of bright pulses produced in free space devices can be found in a large set of applications and research equipment all over the world. The production of dark pulses in a free-space device has not been shown prior to this work. In this work a method of producing free space mode-locked laser in a straight laser cavity using intra-cavity loss induced by periodic nonlinear interactions mediated by a mode-locked source. We are able to show the existence of a dark pulse propagating inside of the cavity. An extensive analysis of the generation of the dark pulse is made using a homemade cross correlator. A symmetric dark pulse with a 10 ps width is achieved with a 90% modulation depth. This work will be used in a continued project involving passive two-color pulse synchronization.<br>Framtagningen av ljusa pulser i kristall baserade lasrar finns i en stor utsträckning av tillämpningar inom forskning och industri. Utvecklandet av mörkpulskällor i kristall baserade kaviteter har till vår kunskap inte tagits fram. I detta arbete presenteras en metod att utveckla en modlåst mörkpuls laser i en rak kavitet som utnyttjar intrakavitär förlust som periodiskt induceras av en ickelinjär interaktion som styrs av en ljus modlåst källa. Vi kan visa att en mörk puls propagerar inuti kaviteten. En utförlig analys och experiment med hjälp av en hemagjord korskorrelator belyser hur den mörka pulsen kan formas. En symmetrisk mörk puls formas med en 10 ps bredd och över 90 % modulations djup. Detta arbete kommer användas i ett framtida projekt inom passiv tvåfärgs puls synkronisation.
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Lopez, Jershon Ysrael. "Demagnetization diagnostics in collisionless space plasma layers." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1684.
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A recently proposed set of demagnetization diagnostics [Scudder et al., submitted to Physics of Plasmas, 2015] is related to the preconditions of Guiding Center Theory (GCT) and benchmarked in kinetic particle-in-cell simulations. Specifically, GCT requires that the time and length scales of the field are long compared to the Larmor motion of the particles. When this condition is violated, the particles become demagnetized and the assumptions of magnetohydrodynamics are no longer valid. In this thesis, these diagnostics are applied to different space plasma layers of different length scales.
In the past, proxy diagnostics that are not based on fundamental GCT conditions have been used to search for, and provide evidence of, demagnetization in different space plasma layers. The problem with these proxy diagnostics is that they are not invertible to demagnetization. The diagnostics presented in this thesis are not only unique to demagnetization, but also have the additional advantages of being dimensionless, scalar, and independent of coordinate system. These diagnostics are applied to three space plasma layers of different length scales, resulting in new insights and methods for detecting particle demagnetization.
First, the evidence for wave heating in the solar wind is reexamined through its fundamental assumptions of demagnetization. The proxy diagnostic commonly used for demagnetization is non-conservation of the Chew-Goldberger-Low conserved quantity. This diagnostic is a good proxy for the first adiabatic invariant in the supersonic regime. To test this and compare it to the assumptions of the Helios analysis [Marsch et al., Journal of Geophysical Research: Space Physics, 88(A4), 1983], the solar wind is modeled through a self-consistent Vlasov mapping. In addition, other experimental assumptions in that same Helios analysis are also examined.
Second, a new method for estimating local length scales is demonstrated across a known bow shock crossing. This new method, based on one of the demagnetization diagnostics, is different from current methods in that it can be performed with single spacecraft data and does not require a special coordinate system.
Third, a new set of invertible signatures of the electron diffusion region (EDR) is introduced and applied to five magnetopause events to search for layers of collisionless magnetic reconnection. Four of these magnetopause events have not been identified before in the literature. The five EDR diagnostics are large electron pressure anisotropy, non-perturbative GCT expansion parameters, order one electron pressure agyrotropy, and order one electron thermal mach number. These EDR diagnostics are compared to a wide range of degenerate diagnostics that are commonly used in reconnection studies. The results of this analysis show that, compared to these degenerate diagnostics, the EDR diagnostics are much more surgical in their identification of electron-scale current layers.
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Zheng, Sue M. Eng Massachusetts Institute of Technology. "Tracking algorithms under boundary layer effects for free-space optical communications." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/53185.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 87-88).<br>Free-space optical communication requires accurate tracking to maintain links. The tracking problem between an aircraft and satellite becomes more difficult with the introduction of a turret on the aircraft for increased field-of-regard. In the case of a hemispherical turret, the disrupted airflow at the boundary layer can greatly distort the optical beam. A model of the communication link is created to compare the performance of several tracking algorithms. We investigate the best algorithm under various atmospheric conditions and signal-to-noise ratios.<br>by Sue Zheng.<br>M.Eng.
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Modi, Sohrab. "Free space laser communications on the Macintosh computers /." Online version of thesis, 1990. http://hdl.handle.net/1850/10547.
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Hassall, G. "Space charge layers in a double plasma machine." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303608.
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Finkelberg, Amanda (Amanda Suzanne). "Space, place, and database : layers of digital cartography." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39155.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Comparative Media Studies, 2007.<br>Includes bibliographical references (leaves 65-68).<br>This paper addresses the changes in cartography since digitization and widespread popular dissemination. Cybercartography, an emergent system of maps, mapmaking tools, and mapmakers, forces a rethinking of spatial representations. The implicit distinction in digital media enables a new type of map user or neo-geographer that creates layers of expressions based on subjective experience. This paper argues that the neo-geographer signifies a new cartographic behavior that affords a complex subjectivity. This behavior is further exhibited in the practice of navigable maps and virtual globes which lead the way to a paradigmatic change in the way we represent and interact with space. It is divided into three parts: Part I addresses the role of digitization in maps and lays out framework and vocabulary. Part II examines layers of spatial representations in historical context. Part III opens room for future study in the quickly developing inhabitable cartographic spaces of virtual globes and virtual worlds.<br>by Amanda Finkelberg.<br>S.M.
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Snook, Daniel Edwin. "Exploring the Book Through Layers of Public Space." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/33461.
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In todayâ s society, awash with digital media, the physical book should still
be treated as a valuable object. It is a symbol of knowledge and, in the
same way that the stones of historic buildings tell the story of their times,
the physical book carries the truths of the past to each new generation,
not only by the words it contains, but in how it is bound and set and
worn. The library rises around the book, offering shelves that may be
explored, allowing people to discover as they browse. The neighborhood
library serves as an anchor for the community; without physical books, the
library is gutted of its essential purpose, becoming merely a community
gathering place.
Members of the community must be given space to move through the
books as they progress from the public realm of the street into the semipublic
space of a library reading room, and perhaps beyond to their private
places of study. Each stage of their journey should be a clearly defined
â placeâ with its own purpose and potential. At the same time, the spatial
boundaries in this progression must be integrated in order to invite people
to move from one to another, to discover the books and the knowledge
contained within. My thesis project has explored and developed these
theoretical ideas into a library and housing project for Washington, DCâ s
West End neighborhood.<br>Master of Architecture
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Hill, Christopher John. "Satellite laser ranging and some geophysical applications." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328388.
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Ikpe, Stanley A. Triplett Gregory Edward. "Atmospheric effects on near-infrared free space optical communication links." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6654.
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Title from PDF of title page (University of Missouri--Columbia, viewed on March 10, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Gregory E. Triplett Jr. Includes bibliographical references.
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Chelaru, Liviu Ionut. "Microscopic studies of interlayer magnetic coupling across nonmagnetic and antiferromagnetic spacer layers." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970939299.
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Dzemiantsova, Liudmila [Verfasser]. "Magnetic Coupling of Individual Atoms through Non-magnetic Spacer Layers / Liudmila Dzemiantsova." München : Verlag Dr. Hut, 2013. http://d-nb.info/1031844872/34.
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Bait, Shiginah Fahad Awadh. "Multi-Layer Cellular DEVS Formalism for Faster Model Development and Simulation Efficiency." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/193709.
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Recent research advances in Discrete EVent system Specification (DEVS) as well as cellular space modeling emphasized the need for high performance modeling methodologies and environments. The growing demand for cellular space models has directed researchers to use different implementation formalisms. Many efforts were dedicated to develop cellular space models in DEVS in order to employ the advantage of discrete event systems. Unfortunately, the conventional implementations degrade the performance in large scale cellular models because of the huge volume of inter-cell messages generated during simulation. This work introduces a new multi-layer formalism for cellular DEVS models that assures high performance and ease of user specification. It starts with the parallel DEVS specification layer and derives a high performance cellular DEVS layer using the property of closure under coupling. This is done through converting the parallel DEVS into its equivalent non-modular form which involves computational and communication overhead tradeoffs. The new specification layer, in contrast to multi-component DEVS, is identical to the modular parallel DEVS in the sense of state trajectories which are updated according to the modular message passing methodology. The equivalency of the two forms is verified using simulation methods. Once the equivalency has been ensured, analysis of the models becomes a decisive factor in employing modularity in cellular DEVS models. Non-modular models show significant speedup in simulation runs given that their event list handler is implemented based on analytical and experimental survey that involve actual operation counts. However, the new high performance non-modular specification layer is complicated to implement. Therefore, a third layer of specification is proposed to provide a simple user specification that is automatically converted into the fast complex cellular DEVS specification, which is finally put in the standard parallel DEVS specification. A tool was implemented to automatically accept user's model specification via GUI and generate the models using the new specifications. The generated models are then required to be tested and verified using some automatic DEVS verification methods. As a result, the model development and verification processes are made easier and faster.
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Kim, Euree Y. "Packet delay and sequence number space in the radio link protocol layer." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/46217.
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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.<br>Includes bibliographical references (leaf 85).<br>by Euree Y. Kim.<br>S.B.and M.Eng.
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Sun, Xiaole, and Ivan B. Djordjevic. "Physical-Layer Security in Orbital Angular Momentum Multiplexing Free-Space Optical Communications." IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2016. http://hdl.handle.net/10150/615106.
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The physical-layer security of a line-of-sight (LOS) free-space optical (FSO) link using orbital angular momentum (OAM) multiplexing is studied. We discuss the effect of atmospheric turbulence to OAM-multiplexed FSO channels. We numerically simulate the propagation of OAM-multiplexed beam and study the secrecy capacity. We show that, under certain conditions, the OAM multiplexing technique provides higher security over a single-mode transmission channel in terms of the total secrecy capacity and the probability of achieving a secure communication. We also study the power cost effect at the transmitter side for both fixed system power and equal channel power scenarios.
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Bolon, Bruce T. "Space-charge waves in a raman free-electron laser /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9988648.
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McMullan, A. E. "Between spaces : the dynamic principle in Samuel Beckett's later drama." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233112.
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Yoon, Seungil. "Cross-layer dynamic spectrum management framework for the coexistence of white space applications." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/44787.
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The objective of this dissertation is to propose the cross-layer spectrum management architecture for white space applications that improves the performance the main functions of the spectrum management. In the proposed cross-layer architecture, white space network devices such as white space devices and the spectrum map server cooperate to support the extended spectrum map, the inter-cell transmit power adaptation (ITPA), and the frequency-domain coexistence beacon (FCB). Upon the cross-layer architecture, firstly, white space devices (WSDs) achieve a faster search and higher accuracy in spectrum sensing with the extended spectrum map, the extended DHCP (Dynamic Host Configuration Protocol), and the FCB. Secondly, WSDs achieve the precise selection of their operating channel in spectrum decision with the extended spectrum map and the ITPA. In spectrum sharing, thirdly, the collaboration- based spectrum sharing with the ITPA achieve more accommodation of WSDs by increasing the number of channels shared between WSDs. Finally, WSDs with the FCB and the extended spectrum achieve effective spectrum mobility by obtaining the occupancy-status of channels precisely.
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Wu, Wenyi. "Space Charge Doped p-n Junction : 2D Diode with Few-layer Indium Selenide." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS449.
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Ce travail allie les propriétés singulières des matériaux 2D à une technique innovante utilisée pour modifier les propriétés électroniques des films ultra-minces pour proposer une nouvelle technologie permettant de réaliser le dispositif électronique le plus simple, la diode. Tout d'abord, nous identifions les matériaux semi-conducteurs pouvant être fabriqué en couches ultra-minces. Deuxièmement, nous utilisons une technique appelée dopage par charge d'espace développée dans notre groupe pour le dopage n ou p des matériaux. Enfin, nous obtenons les caractéristiques de diode des dispositifs. Le manuscrit commence par une revue des matériaux. Dans la famille des matériaux 2D, notre choix s'est porté sur un semi-conducteur en couches III-VI avec une bande interdite directe : InSe. Nous avons aussi choisi un type de matériau très différent, le CdO polycristallin qui n'est pas lamellaire et n'a pas une bande interdite directe, mais qui est facile à fabriquer sous forme de film ultra-mince avec une grande mobilité de porteurs. Après des expériences préliminaires, nous avons choisi InSe et fabriqué des dispositifs de films ultra minces de InSe. Nous avons développé en parallèle deux géométries pour la diode p-n. Nous avons pu obtenir un redressement pour chaque géométrie, ce qui implique que notre approche de dopage par charge d'espace a réussi à produire un dopage différencié spatialement dans chaque dispositif. Nous discutons des caractéristiques I-V obtenues et les limitations inhérentes aux dispositifs (chauffage local, hystérèses) et suggérons des améliorations afin d'obtenir un fonctionnement plus efficace et stable dans le cadre des perspectives de cette thèse<br>This work combines the singular properties of 2D materials with an innovative technique used for changing the electronic properties of ultra-thin films to propose a new technology for making the simplest bipolar electronic device, the diode. Firstly we identify semiconducting materials which can be fabricated in ultra-thin layers. Secondly, we use a proprietary technique called Space Charge Doping developed in our group for doping the material, either n or p. Finally, we obtain diode characteristics from the device. The manuscript begins with a review of different materials and properties. In the family of 2D materials, our choice was a III-VI layered semiconductor with a direct bandgap: InSe. We also chose a completely different kind of material, polycrystalline CdO, which is neither layered nor has a direct bandgap but is easy to fabricate in the ultra-thin film form and has high carrier mobility. After preliminary experiments, we chose InSe and fabricated devices of ultra-thin, few atomic layer InSe thin films. We chose to develop in parallel two different geometries for the p-n junction diode. We were able to obtain rectifying behavior for each geometry implying that our space charge doping approach was successful in producing microscopically, spatially differentiated doping in each device. We discuss the obtained I-V characteristics and the inherent limitations of the devices (local heating, hysteresis) and suggest improvements for future experiments and ways of obtaining more efficient and stable functioning and geometry as part of the perspectives of this thesis
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Mattingly, Sean Walter. "Velocity space degrees of freedom of plasma fluctuations." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5967.
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This thesis demonstrates a measurement of a plasma fluctuation velocity-space cross-correlation matrix using laser induced fluorescence. The plasma fluctuation eigenmode structure on the ion velocity distribution function can be empirically determined through singular value decomposition from this measurement. This decomposition also gives the relative strengths of the modes as a function of frequency. Symmetry properties of the matrix quantify systematic error. The relation between the eigenmodes and plasma kinetic fluctuation modes is explored. A generalized wave admittance is calculated for these eigenmodes. Since the measurement is a localized technique, it may be applied to plasmas in which a single point measurement is possible, multipoint measurements may be difficult, and a velocity sensitive measurement technique is available.
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Youssef, Hazim S. "Laser engine simulation using pressure based navier-stokes solver." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10052007-143624/.
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Timus, Oguzhan. "Free space optic communication for Navy surface ship platforms." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FTimus.pdf.
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Mahajan, Pankaj. "Space: Working and Living." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/34071.
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what is architecture?
what defines space?
how do you define separation and integration of spaces?
what is the relationship of human scale to space elements?
how can architecture be studied?
Architecture is an combination of science and art to make spaces for human needs and activities. What can an architect do to make a project, a building, not only serve its purpose but to go beyond that? A space supports human desire and imagination. Architecture provides the means and methods to make the spaces. The elements of the structure, column, wall, beam, and floor, play a very important role in defining and/or dividing a space. A room can be defined by four walls, columns or even beams. The material of the floor also outlines space. Walls, a series of columns, or ceiling beams can define an edge or enclose space and differentiate its meaning and function. The understanding of these elements and their relationship with each other and with people is the purpose of this study.
In an urban situation often there is a need to design buildings with spaces for multiple activities. Separation of spaces and functions, as well as integration of different parts, is vital in such a design. Columns and walls enclose the space and characterize privacy. Their material and its characteristics make the edges of space opaque, transparent or semitransparent. The dimensions of columns and beams show the scale of the space, constraining the relationship of the people to the structural elements.<br>Master of Architecture
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Pollack, Scott E. "Analytic and interferometric techniques for the Laser Interferometer Space Antenna." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/dissertations/fullcit/3178330.
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Bassom, Neil James. "Magnetotransport studies of space charge layers in narrow-gap semiconductors." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291070.
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Krishen, Kumar, and Harry O. Erwin. "REVIEW OF LASER AND RF SYSTEMS FOR SPACE PROXIMITY OPERATIONS." International Foundation for Telemetering, 1986. http://hdl.handle.net/10150/615591.
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International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada<br>This paper presents a review of the ranging and tracking systems/techniques used in the past NASA programs. A review of the anticipated requirements for future rendezvous and docking operations is also presented as rationale for further development of the technology in this area. The first American rendezvous in space was between Gemini VI-A and Gemini VII and took place on December 15, 1965. The Gemini vehicles were equipped with a noncoherent pulse radar. The target vehicle carried a transponder to assist the radar in target acquisition. Angle tracking was accomplished by the phase-comparison monopulse technique. In the Gemini, Apollo, and Skylab programs, the rendezvous and/or docking were manual operations supported by radar measurements and visual observations. The Shuttle rendezvous radar is a Ku-band, pulse-Doppler radar which doubles as a communications transceiver. This radar is not accurate enough to support close-in stationkeeping or docking. An automatic soft-docking capability has been established as a requirement for future space operations. Millimeter wave and laser radar systems have shown promise in satisfying the needed accuracy requirements and size constraints (for space applications) compared to the microwave systems for proximity attitude, position and velocity measurements. A review of these systems and their capabilities is presented in this paper. Rather than developing a separate sensor to satisfy the requirements of each new spacecraft, a hybrid design is proposed for a versatile system which can satisfy the needs for different spacecrafts and missions.
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Raible, Daniel Edward. "Free Space Optical Communications with High Intensity Laser Power Beaming." Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1313065631.
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Goh, Allex. "Electrostatics problems relating to the laser interferometer space antenna mission /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Ricklin, Jennifer C. "Free-space laser communication using a partially coherent source beam." Available to US Hopkins community, 2002. http://wwwlib.umi.com/dissertations/dlnow/3046547.
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Mwakali, Jackson Aarali. "The collapse behaviour of double-layer space trusses incorporating eccentrically loaded tee-section members." Thesis, University of Surrey, 1990. http://epubs.surrey.ac.uk/756/.
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Elabd, Maher Mostafa Abdel-Hakeem. "Effect of composite action on the dynamic behaviour of space structures." Thesis, University of Dundee, 2010. https://discovery.dundee.ac.uk/en/studentTheses/99b1ba2d-af1e-4c64-b184-f9f52afcf722.
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The application of composite action ushered a new era in the use of double-layer spaceframes as efficient floor systems in addition to their competitiveness as roof coveringstructural systems. Earlier research on space frames demonstrated large improvementsin their static behaviour caused by the introduction of composite action. Theseimprovements included an increase in ductility to avoid progressive collapse, a largeincrease in load-carrying capacity and a considerable reduction in materialconsumption.In this work, the effect of introducing composite action in changing the dynamiccharacteristics of space frames, in particular the natural frequencies and damping ratioswas presented. The study was expanded to determine the effect of composite action inchanging the response to dynamic excitations. The measured responses included thelateral displacements and changes in the internal member force distribution undershaking table vibrations.Three aluminium space frame models of the square on square (SOS) configuration weremanufactured. The first model was non-composite, while composite action was appliedto the other two models with a top aluminium deck and a timber deck, respectively.Two common cases of support conditions were used in connecting the models to theloading frame, which was the platform of the shaking table.Initial displacement method (snap test) was used to determine the frequency of vibrationand the damping ratio of test models in the vertical and horizontal directions usinglogarithmic decrement method. All models were then exposed to shaking tablevibrations to determine the changes in dynamic responses between different models.These tests were repeated for the three models after the successive removal of panelsfrom one direction to identify the changes to their characteristics and behaviour withdifferent aspect ratios.The second part of the study was carried out numerically by using the finite elementpackage ABAQUS. It started by selecting a valid finite element model from nineproposed models using experimental test results on physical structures. A parametricstudy was conducted using the validated finite element model to expand the study toinclude two common space frame configurations; the square on large square (SOLS)and square on diagonal (SOD), and two other cases of support configurations, namely,fully edge-supported and supports at corners and middle edges of models.Based on the work done in this study, it can be concluded that composite actionchanged the dynamic characteristics of space frames, which was clear in the increase oftheir vibration frequencies in all directions as a result of the increase in stiffness.Furthermore, the increase in stiffness resulted in a general reduction in the dampingratio of space frames covered with aluminium deck, while the high friction with topjoints and the nature of timber as a good energy absorbent material resulted in a variableeffect on the damping ratio associated with the increase in aspect ratio.The effect of composite action was clear in reducing the lateral displacement ofcomposite models by more than 50% compared to the non-composite case. Moreover,composite action resulted in changing the distribution of internal forces in diagonal andlower chord members such that forces became more concentrated at corners and edgesparallel to the direction of vibrations in both cases of corner and edge-supportedmodels.
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Balantrapu, Neehar Agastya. "The Space-time Structure of an Axisymmetric Turbulent Boundary Layer Ingested by a Rotor." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/103258.
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A low-speed, axisymmetric turbulent boundary layer under a strong adverse pressure gradient is experimentally studied for its relevance to marine applications, urban air-transportation and turbulence ingestion noise. The combined effect of lateral curvature and streamwise pressure gradient are examined on the mean flow, turbulence structure, velocity correlations and wall pressure fluctuations. Additionally, the upstream influence of a rotor operating in this flow is examined to improve the understanding of the turbulence necessary to develop advanced noise prediction tools. Measurements were made in Virginia Tech Stability tunnel documenting the flow over a 0.432-m diameter body-of-revolution comprised of a forward nose-cone, a constant diameter mid-body and a 20 degree tail-cone, at a length based Reynolds number of 1.2 million.
The principal finding of this work is the resemblance of the boundary layer to a free-shear layer where the turbulence far from the wall plays a dominant role, unlike in the canonical case of the flat-plate boundary layer. The mean flow along the tail developed inflection points in the outer regions and the associated velocity and turbulence stress profiles were self-similar with a recently proposed embedded shear layer scaling. As the mean flow decelerates downstream, the large-scale motions energize and grow along with the boundary layer thickness; However, the structure is roughly self-similar with the shear-layer scaling, emphasizing the role of the shear-layer in the large-scale structure. Additionally, the correlation structure is discussed to provide information towards the development of turbulence models and aeroacoustic predictions.
The associated wall pressure fluctuations, measured with a longitudinal array of microphones, evolved significantly downstream with the dimensional wall pressure spectra weakening by over 20-dB per Hz. However, the spectra collapsed to within 2-dB with the wall-wake scaling, where the pressure-scale is the wall shear stress, and the time-scale is derived from the boundary layer thickness and edge velocity. The success of this scaling, even in the viscous roll-off regions, suggests the increasing importance of the outer region on the near-wall turbulence and wall-pressure. Investigation of the space-time structure revealed the presence of a quasi-periodic feature with the conditional signature of a roller-eddy. The structure appeared to scale with the wall-wake scaling, and was found to convect downstream at speeds matching those at the inflection points (and outer turbulence peak). It is hypothesized that the outer region turbulence in strong adverse pressure gradient flow strongly drive the near-wall turbulence and therefore both the wall pressure and shear stress.
Subsequent measurements made with the rotor operating at the tail, using high-speed particle image velocimetry, provided the space-time structure of the inflow turbulence as a function of the rotor thrust. The impact of the rotor on the mean flow, turbulence and correlation structure in the vicinity of the rotor is discussed to supply information towards validating numerical simulations and developing turbulence models that account for the distortion due to the rotor.
This work was sponsored by the Office of Naval Research, in particular Drs. Ki-Han Kim and John Muench under grants N00014-17-1-2698 and N00014-20-1-2650.<br>Doctor of Philosophy<br>Understanding turbulent flows adjacent to surfaces placed in fluid flows is necessary to develop efficient technologies to mitigate undesirable drag, vibrations and noise. Particularly, this is of an increased interest with the imminent abundance of urban short-haul air transportation. While several fundamental aspects of these flows have been clarified, certain specific areas still remain to be addressed, including the impact of curved surfaces, like those of submarine hulls and aircraft fuselage, and the impact of mean pressure gradients.
This study seeks to fill some of these gaps by studying the flow over a body-of-revolution through wind tunnel experiments. The nature of the velocity and wall-pressure fluctuations are examined in detail. It was found that the boundary layer was significantly different from the canonical case of a flat-plate flow, with the mean velocity and turbulence structure developing the characteristics of a free-shear layer (flows unbounded by surfaces). Specifically, the velocity and turbulence intensity appeared self-similar with a recently proposed embedded shear layer scaling, which is based on the parameters at the inflection point in the mean velocity profile. The large-scale motions in the outer regions, despite energizing and growing as the flow decelerated downstream, appeared self-similar with the shear layer parameters, emphasizing the role of shear layer motions within in the boundary layer. This is important since the turbulence relatively further from the wall are now the important sources of pressure fluctuations and therefore drag, vibrations and noise. The associated wall-pressure fluctuation were studied with a focus on the wall-pressure spectrum and the space-time structure. A quasi-periodic feature was detected in the instantaneous fluctuations, which had a conditional structure reminiscent of a conditional roller, and appeared to convect downstream at speeds matching those at the inflection points in the velocity profile. Therefore it is hypothesized that the large-scale motions in the embedded shear layer play a dominant role on the near-wall turbulence and therefore on the wall pressure and shear-stress. This is different from the behavior of the wall-studied flow past a flat-plate. It is therefore important to factor this into technologies aiming to increase the efficiency and quieten the vehicles
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Yoshida, Brian Richard. "Compuational analysis of boundary layer control by suction in a space transfer vehicle engine turbopump diffuser /." Online version of thesis, 1992. http://hdl.handle.net/1850/11058.
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Urech, Lukas. "Design and characterization of energetic polymers applied in laser space propulsion /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17068.
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Paeng, Dong-Guk 1966. "Normal mode acoustic scattering considering elastic layers over a half space." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43546.
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