Performance study of high resolution algorithms in sonar signal processing

In the last two decades or so there has been great interest in the problem of estimating signal parameters from the measurements at sensor array outputs. The most important parameters are probably the directions-of-arrival (DOAs) at the array from radiating sources in the observed spatial field. This thesis is devoted to the study of algorithms and techniques which have been suggested from different points of view for the same direction estimation problem. Several classes of algorithms are examined which include the conventional beamforming methods, eigenstructure based algorithms, subspace rotation methods, decompositions techniques, and the more recently proposed weighted subspace fitting methods. The research in this thesis contains three main aspects addressing theoretical analyses, computer simulations, and practical experiments respectively. A set of simulation programs has been developed to evaluate the performance in various scenarios, and Monte Carlo tests have been carried out to support theoretical analyses. The simulation work was carried out on an IBM PC, and the computer language used was MATLAB (Matrix Laboratory), a package especially developed for matrix computations. A sonar system available in the sonar research group at Loughborough University of Technology (LUT) was modified and used to collect real data for off-line processing so as to demonstrate the algorithm performance in real experimental environments. Two scenarios were examined when the system worked in passive and active modes respectively. In the passive working mode, two emitters were employed to give uncorrelated or strongly correlated signals by using the same or different working frequencies. When working in the active mode, a single sensor was placed on the top of the receiving array which received reflections from two targets in the distance. The data was captured and then saved on floppy disks from the measurement system and processed on PCs. A large number of results are presented, analysed, and summarized in the thesis, including· both computer simulations and practical measurements. This provides a fundamental ground for further work in this and related areas

Rhodium(III)-Catalyzed Indole Synthesis Using N–N Bond as an Internal Oxidant

We report herein a Rh­(III)-catalyzed cyclization of <i>N</i>-nitrosoanilines with alkynes for streamlined synthesis of indoles. The synthetic protocol features a distinct internal oxidant, N–N bond, as a reactive handle for catalyst turnover, as well as a hitherto tantalizingly elusive intermolecular redox-neutral manifold, predicated upon C–H activation, for the formation of a five-membered azaheterocycle. The compatibility of seemingly dichotomous acidic and basic conditions ensures reaction versatility for multifarious synthetic contexts. The tolerance of an array of auxiliary functional groups potentially permits predefined, programmable substitution patterns to be incorporated into the indole scaffold. Comprehensive mechanistic studies, under acidic condition, support [RhCp*]²⁺ as generally the catalyst resting state (switchable to [RhCp*­(OOC^<i>t</i>Bu)]⁺ under certain circumstance) and C–H activation as the turnover-limiting step. Given the variety of covalent linkages available for the nitroso group, this labile functionality is likely to be harnessed as a generic handle for strikingly diverse coupling reactions

Rhodium(III)-Catalyzed Indole Synthesis Using N–N Bond as an Internal Oxidant

We report herein a Rh­(III)-catalyzed cyclization of <i>N</i>-nitrosoanilines with alkynes for streamlined synthesis of indoles. The synthetic protocol features a distinct internal oxidant, N–N bond, as a reactive handle for catalyst turnover, as well as a hitherto tantalizingly elusive intermolecular redox-neutral manifold, predicated upon C–H activation, for the formation of a five-membered azaheterocycle. The compatibility of seemingly dichotomous acidic and basic conditions ensures reaction versatility for multifarious synthetic contexts. The tolerance of an array of auxiliary functional groups potentially permits predefined, programmable substitution patterns to be incorporated into the indole scaffold. Comprehensive mechanistic studies, under acidic condition, support [RhCp*]²⁺ as generally the catalyst resting state (switchable to [RhCp*­(OOC^<i>t</i>Bu)]⁺ under certain circumstance) and C–H activation as the turnover-limiting step. Given the variety of covalent linkages available for the nitroso group, this labile functionality is likely to be harnessed as a generic handle for strikingly diverse coupling reactions

Efficiency detection of adiponectin expression in chicken preadipocytes.

<p>(A) GFP observed by fluorescence microscopy 24 h after transfection with pGPU6 recombinant vectors. Scale bar, 100 µm. (B) The expression of <i>adiponectin</i> gene 24 h after transfection with pcDNA3.1-ADPN and pGPU6 recombinant vectors (n = 3). (C) The expression of adiponectin protein at day 2, 3 and 9 after transfection with pcDNA3.1-ADPN and siRNA-3 (n = 3). CK: Control group, pC: pcDNA3.1, pA: pcDNA3.1-ADPN, pG: pGPU6/GFP/Neo, siRNA-1: pGPU6/GFP/Neo-ADPN-676, siRNA-2: pGPU6/GFP/Neo-ADPN-751, siRNA-3: pGPU6/GFP/Neo-ADPN-952, siGH: pGPU6/GFP/Neo- siGAPDH. Values are means ± SEM. vs. control group, * <i>P</i><0.05, ** <i>P</i><0.01.</p

Adiponectin activates the p38 MAPK/ATF-2 pathway in cultured chicken preadipocytes.

<p>(A) Cells were treated either with recombination vectors alone or with 10 µM SB253580(SB), total proteins were extracted at 30 min after administration of SB253580 and then immunoblotted for total p38MAPK, phospho-p38MAPK (pT180/pY182), total ATF-2 and phospho-ATF-2 (pT71) (n = 3). (B) Representative images of Oil Red O-stained sections of cells at d 9 after treated either with recombination vectors alone or with 10 µM SB253580. (C) Lipid accumulation was assessed by the quantification of A₅₁₀ in destained Oil Red O with isopropyl alcohol (n = 3). Scale bar, 100 µm. CK: Control group, pC: pcDNA3.1, pA: pcDNA3.1-ADPN, pG: pGPU6/GFP/Neo, siRNA-3: pGPU6/GFP/Neo-ADPN-952, siGH: pGPU6/GFP/Neo-GAPDH. Values are means ± SEM. vs. control group, * <i>P</i><0.05, ** <i>P</i><0.01. vs. SB253580 treatment group, # <i>P</i><0.05, ## <i>P</i><0.01.</p

Effects of adiponectin on sequential expression of lipogenesis genes and proteins.

<p>(A) Expression levels of adipogenesis genes at day 1, 3 and 9 after transfection with pcDNA3.1-ADPN and siRNA-3 (n = 3). (B) Expression levels of adipogenesis proteins at day 1, 3 and 9 after transfection with pcDNA3.1-ADPN and siRNA-3 (n = 3). CK: Control group, pA: pcDNA3.1-ADPN, siRNA-3: pGPU6/GFP/Neo-ADPN-952. Values are means ± SEM. vs. control group, * <i>P</i><0.05, ** <i>P</i><0.01.</p

Effects of adiponectin on morphology changes and lipid metabolism of cultured chicken preadipocytes.

<p>(A) Representative images of Oil Red O-stained sections of three groups at day 1, 3 and 9. Scale bar, 100 µm. (B) Lipid accumulation was assessed by the quantification of A₅₁₀ in destained Oil Red O with isopropyl alcohol (n = 3). (C) The areas stained with Oil Red O assessed (n = 3). (D) Lipid droplet diameter frequency distributions for the three groups. Numbers on the x-axis represent the bins for droplets of specific sizes. (E) Glycerol content in the medium (n = 3). (F) FFA content in the cell culture medium (n = 3). FFA: free fatty acid, CK: Control group, pA: pcDNA3.1-ADPN, siRNA-3: pGPU6/GFP/Neo-ADPN-952. Values are means ± SEM. vs. control group, * <i>P</i><0.05, ** <i>P</i><0.01.</p

List of genes examined and their corresponding accession numbers.

<p>Footnote: F and R indicate forward and reverse primers respectively. <i>GAPDH  =  Glyceraldehyde 3-phosphate de-hydrogenase</i>, <i>C/EBPα  =  CCAAT/enhancer binding protein alpha</i>, <i>PPARγ  =  Peroxisome proliferator-activated receptor gamma</i>, <i>FAS  =  fatty acid synthase, ATGL  =  adipose triglyceride lipase</i>.</p

Use of isochrone maps to assess the impact of high-speed rail network development on journey times: a case study of Nanjing city, Jiangsu province, China

<p>It is well known that the increasing development of transport infrastructure will result in temporal and spatial convergence. As an important component of China’s high-speed rail (HSR) network, an ambitious HSR building program in Jiangsu province will extend the network to cover all cities and 95% of counties by 2030. This study aims to present and analyze the impacts of the evolving HSR network in Jiangsu province over the period of 2010–2030 by developing multi-phased isochrone maps of Nanjing city (the provincial capital of Jiangsu province). During the process, layered cost distance, a new method based on a door-to-door approach in actual travel time calculations, is proposed in order to draw the maps at a more detailed geographical level. Our results are expected to facilitate proactive public policy decisions related to improving the transport network.</p

Use of isochrone maps to assess the impact of high-speed rail network development on journey times: a case study of Nanjing city, Jiangsu province, China

<p>It is well known that the increasing development of transport infrastructure will result in temporal and spatial convergence. As an important component of China’s high-speed rail (HSR) network, an ambitious HSR building program in Jiangsu province will extend the network to cover all cities and 95% of counties by 2030. This study aims to present and analyze the impacts of the evolving HSR network in Jiangsu province over the period of 2010–2030 by developing multi-phased isochrone maps of Nanjing city (the provincial capital of Jiangsu province). During the process, layered cost distance, a new method based on a door-to-door approach in actual travel time calculations, is proposed in order to draw the maps at a more detailed geographical level. Our results are expected to facilitate proactive public policy decisions related to improving the transport network.</p