Parallel Linear Arrays Research Articles

Accuracy analysis of indirect georeferencing about TH-1 satellite in Weinan test area

Optical linear scanning sensors can be divided into single-lens sensors and multi-lens sensors according to the number of lenses. In order to build stereo imaging, for single-lens optical systems such as aerial mapping camera ADS40 and ADS80, there are more than two parallel linear arrays placed on the focal plane. And for a multi-lens optical system there is only one linear CCD arrays placed on the center of every focal plan for each lens which is often carried on spacecraft. The difference of design between these two kinds of optical systems leads to the systematic errors, calibration in orbit and approach of data adjustment are different completely. Recent years the domestic space optical sensor systems are focused on multi-lens linear CCD sensor in China, such as TH-1 and ZY-3 both belong to multi-lens optical systems. The parameters influencing the position accuracy of the satellite system which are unknown or unknown precisely even changed after sensor posted launch can be estimated by self-calibration in orbit. So after self-calibration in orbit the accuracy of mapping satellite will often be improved strongly. Comparing to direct georeferencing, the indirect georeferencing as a research approach is introduced to TH-1 satellite in this paper considering the systematic errors completely. Parameters about geometry position systematic error are introduced to the basic co-linearity equations for multi-lenses linear array CCD sensor, and based on the extended model the method of space multi-lens linear array CCD sensor self-calibration bundle adjustment is presented. The test field is in some area of Weinan, Shaanxi province, and the observation data of GCPs and orbit are collected. The extended rigors model is used in bundle adjustment and the accuracy analysis shown that TH-1 has a satisfied metric performance.

用于声矢量阵列波达方向估计的四元数最小范数法

To reduce the calculation amount of quaternion Multiple Signal Classification(MUSIC)algorithm,a Minimum Norm(MN)quaternion method based on the quaternion form of an acoustic sensor vector was proposed for estimating Direction of Arrival(DOA).First,based on the MN principle,the(M-N)×Mdimension(Mis the number of array sensors,Nis the number of signal sources)orthogonal noise subspace vectors were converted to a 1×M dimension quaternion noise vector.Then,a simplified formula for peak search was proposed.The searching computation amount of Quaternion MN(Q-MN)was analyzed theoretically.Compared with the Q-MUSIC algorithm,the Q-MN algorithm can save at least 50% of the peak search volume.Experimental results show that the orthogonality of the steering vector with the low-dimensional noise vector derived by proposed methodis superior to that with high dimensional noise subspace.When the Signal to Noise Ratio(SNR)is 0dB,the Vandermonde norm and the spatial spectrum peak value of Q-MN algorithm are 1/3 times and 3 times as much as those of Q-MUSIC.The Q-MN algorithm can successfully identify the DOA of signal sources,and its resolution is equivalent to that of Q-MUSIC algorithm.Moreover,it can be applied to not only L-shaped arrays,but also plane arrays and parallel linear arrays.

Differential feeding technique for mm‐wave series‐fed antenna‐array

A differential feeding technique for a broadband planar antenna-array is presented. The antenna structure is composed of four parallel linear series-fed arrays of four microstrip patches. To cancel the beam tilt versus frequency, one side of the array is fed with in-phase signal, whereas the same out-of-phase signal feeds the opposite side of the array. A rat-race balun is especially designed to generate those two signals. In comparison with other feeding techniques, there is no need for a resistive load which is actually a problem at millimeter (mm)-wave frequencies. To validate the concept, a 60 GHz prototype etched on the TacLamPlus substrate is designed and measured.

Isolated Unilateral Linear Epidermal Nevus of the Upper Eyelid

A 75-year-old man presented with a recurrent, unilateral, solitary, linear, corrugated lesion of the right upper eyelid of prolonged duration together with bilateral dermatochalasis. A re-excision with blepharoplasty was performed. Histopathologic analysis of the tissue revealed parallel linear arrays of papillomatosis and acanthosis with overlying basket-weave hyperkeratosis consistent with a linear epidermal nevus. Immunohistochemical studies disclosed normal numbers of intraepidermal melanocytes and Langerhans cells without Merkel cells or an increase in cycling keratinocytes. Although the term "nevus" is mostly used in conjunction with the common nevomelanocytic nevus, in fact nevi of other cutaneous cellular elements can occur on a malformational basis (such as sebaceous, eccrine, apocrine, pilar, and elastic fiber nevi). Ophthalmologists should be aware of epidermal nevi because they are rarely associated with cataracts, malignant cutaneous neoplasms, neurologic abnormalities, and musculoskeletal disorders. For focal lesions like the present one, local excision is appropriate. A select differential diagnosis of histopathologically related conditions is provided.

Large-Area Organization of pNIPAM-Coated Nanostars as SERS Platforms for Polycyclic Aromatic Hydrocarbons Sensing in Gas Phase

Here, a new surface enhanced Raman spectroscopy (SERS) platform suitable for gas phase sensing based on the extended organization of poly-N-isopropylacrylamide (pNIPAM)-coated nanostars over large areas is presented. This system yields high and homogeneous SERS intensities, and simultaneously traps organic chemical agents as pollutants from the gas phase. pNIPAM-coated gold nanostars were organized into parallel linear arrays. The optical properties of the fabricated substrates are investigated, and applicability for advanced sensing is demonstrated through the detection in the gas phase of pyrene traces, a well-known polyaromatic hydrocarbon.

Traveling waves in two parallel infinite linear point-scatterer arrays

Traveling waves in two coupled parallel infinite linear point-scatterer arrays are studied analytically for the first time to our knowledge. The two arrays are considered to be generally offset in the axial direction. It is found that slow quasi-even/odd supermodes are supported, as a result of the coupling-induced splitting of the modes of the single array, in direct analogy to standard optical waveguide couplers. Exactly even/odd supermodes are supported when the axial offset is zero. Mode splitting, dispersion curves, and coupling length are numerically investigated versus the inter-element spacing, the inter-array distance, and the axial offset. Potential applications of the concept are in directional optical couplers made of metallic or dielectric nanoparticle chains.

Coupling and guided propagation along parallel chains of plasmonic nanoparticles

We derive a dynamic closed-form dispersion relation for the analysis of the entire spectrum of guided wave propagation along coupled parallel linear arrays of plasmonic nanoparticles, operating as optical ‘two-line’ waveguides. Compared to linear arrays of nanoparticles, our results suggest that these waveguides may support more confined beams with comparable or even longer propagation lengths, operating analogously to transmission-line segments at lower frequencies. Our formulation fully takes into account the entire dynamic interaction among the infinite number of nanoparticles composing the parallel arrays, considering also the realistic presence of losses and the frequency dispersion of the involved plasmonic materials, providing physical insights into the guidance properties that characterize this geometry.

Adhesion between plasma membrane and mitochondria with linking filaments in relation to migration of cytoplasmic droplet during epididymal maturation in guinea pig spermatozoa

High-resolution microscopy has been used to investigate the mechanism of the migration of cytoplasmic droplets during epididymal maturation of guinea pig spermatozoa. On testicular spermatozoa, droplets are located at the neck and, after passage through the middle cauda epididymidis, migrate only as far as the center of the midpiece. Initially, the space between the plasma membrane and outer mitochondrial membranes outside the droplet is 30.8+/-11.0 nm, whereas on mature spermatozoa, it significantly (P<0.01) narrows to a more consistent 15.9+/-1.3 nm. This is accompanied by the appearance of thin filaments cross-linking the two membranes above and below the droplet. Changes also occur in the arrangement of intramembranous particles (IMPs) in the plasma membrane overlying the midpiece. At the spermatid stage, linear arrays of IMPs are absent but appear on immature spermatozoa, where they are short with an irregular orientation, in the epididymis. On mature spermatozoa, numerous parallel linear arrays are present at the region where the plasma membrane adheres to the mitochondria. The membrane adhesion process can thus be observed two-dimensionally. The initial migration of the droplet from the neck is probably attributable to diffusion, with the formation of cross-linking filaments between the two membranes in the proximal midpiece preventing any backward flow and squeezing the droplet distally until it is arrested at the central midpiece by the filaments formed in the distal midpiece. The filaments might also stabilize the flagellum against hypo-osmotic stress encountered during ejaculation and within the female tract.

Highly uniform SERS substrates formed by wrinkle-confined drying of gold colloids

SERS substrates were fabricated through self-assembly of gold nanoparticles upon solution-drying in a periodic confining structure. The technique leads to uniform, parallel linear nanoparticle arrays with the precise arrangement defined through the dimensions of the particles and the grooves, which provide high and uniform SERS enhancement over extended areas.

Maximization of noise immunity of a two-layer hydroacoustic antenna

A method of maximizing the noise immunity coefficient of a two-layer hydroacoustic antenna is proposed. An antenna consisting of two parallel linear arrays is considered as an example to estimate the gain in noise immunity achieved with the proposed algorithm against the cardioid-type connection of these arrays.

Multichannel Microchemical Reactor Comprising Replica-Molded Microplasma Devices: Chemiluminescence and Sulfur Deposition in $\hbox{Ar/CS}_{2}$ Flows

Microchemical reactors consisting of parallel linear arrays of interconnected cylindrical microcavity plasma devices have been fabricated by replica molding in ultraviolet-curable polymer. Tests of 10 times 10 arrays of 400-mum-diameter devices with 125-mum-wide gas flow channels have been conducted in rare gas and Ar/CS2 flows and excitation of the array with a sinusoidal voltage. Visible chemiluminescence (lambda ~ 505 nm) resulting from the A tilde rarr X tilde transition of CS2 + and the deposition of a (C-S)n microstructured polymer have been observed in the Ar/CS2 flow experiments.

Overtaking Vehicle Detection Method and Its Implementation Using IMAPCAR Highly Parallel Image Processor

This paper describes the real-time implementation of a vision-based overtaking vehicle detection method for driver assistance systems using IMAPCAR, a highly parallel SIMD linear array processor. The implemented overtaking vehicle detection method is based on optical flows detected by block matching using SAD and detection of the flows' vanishing point. The implementation is done efficiently by taking advantage of the parallel SIMD architecture of IMAPCAR. As a result, video-rate (33 frames/s) implementation could be achieved.

Influence of vanadate on migrating fibroblast orientation within a fibrin matrix

Treating rats with vanadate, a nonspecific inhibitor of protein tyrosine phosphatases, optimizes the uniform packing of collagen fiber bundles in wound granulation tissue and doubles wound breaking strength in rat incisional wounds. The speculation is vanadate optimizes the packing of collagen fiber bundles through the orientation of newly arrived wound fibroblasts in the fibrin clot filling the defect. Segments of 14 day chick embryo tendons were placed on fibrin clots and maintained in organ culture with and without 30 microM vanadate. On day 7 explants were examined histologically and biochemically. Tendon fibroblast outgrowth from untreated explants migrated in a random fashion, while fibroblasts from vanadate-treated explants migrated out in linear arrays. Fibroblasts were elongated by 20% form vanadate treated explant compared to controls. Myosin ATPase, required for optimal cell motility, is optimized by the phosphorylation of its myosin light chain (MLC). Western blot analysis of lysates from the fibroblasts that migrated into the fibrin showed vanadate increased MLC-P levles. These findings support the notion that vanadate promotes the deposition of regular, parallel collagen fiber bundles by advancing the orientation of fibroblasts in parallel linear arrays early in the wound repair process.

Azimuth and elevation estimation for noncircular signals

A novel 2D direction-finding algorithm for noncircular signals using two parallel linear arrays, called the extended rank reduction (ERARE) algorithm, is presented. The method needs only 1D search for joint azimuth and elevation estimation. The azimuth and elevation angles estimated by ERARE are paired automatically.

An Integrated Memory Array Processor for Embedded Image Recognition Systems

Embedded processors for video image recognition in most cases not only need to address the conventional cost (die size and power) versus real-time performance issue, but must also maintain high flexibility due to the immense diversity of recognition targets, situations, and applications. This paper describes IMAP, a highly parallel SIMD linear processor and memory array architecture that addresses these trade-off requirements. By using parallel and systolic algorithmic techniques, but based on a simple linear array architecture, IMAP successfully exploits not only the straightforward per-image row data level parallelism (DLP), but also the inherent DLP of other memory access patterns frequently found in various image recognition tasks, while allowing programming to be done using an explicit parallel C language (1DC). We describe and evaluate IMAP-CE, one of the latest IMAP processors, integrating 128 100 MHz 8 bit 4-way VLIW PEs, 128 2 KByte RAMs, and one 16 bit RISC control processor onto a single chip. The PE instruction set is enhanced to support 1DC code. The die size of IMAP-CE is 11 times11 mm2 integrating 32.7 M transistors, while the power consumption is, on average, approximately 2 watts. IMAP-CE is evaluated mainly by comparing its performance while running 1DC code with that of a 2.4 GHz Intel P4 running optimized C code. Based on the use of parallelizing techniques, benchmark results show a speed increase of up to 20 times for image filter kernels and of 4 times for a full image recognition application

A Proliferative Glomerulonephritis Secondary to a Monoclonal IgA

A distinct entity mimicking immune-complex-mediated glomerulonephritis characterized by a proliferative glomerulonephritis with monoclonal immunoglobulin G (IgG) deposits recently was described. We now report a case of a 35-year-old woman who presented with sudden onset of edema, proteinuria, hematuria, and hypertension. Renal biopsy showed diffuse endocapillary proliferation, mesangial cellularity, and amorphous material in the mesangium. Immunofluorescence examination showed mesangial and capillary wall staining for IgA (2+), C3 (2+), fibrinogen (2+), and lambda (2+). Congo red stain was negative. Electron microscopy showed mesangial and subendothelial deposits with a paracrystalline lattice-like substructure forming parallel linear arrays. Extensive laboratory evaluation showed a small population of monoclonal plasma cells with lambda restriction. The present case suggests that monoclonal IgA deposits also can cause proliferative glomerulonephritis. However, the presence of paracrystalline deposits in association with monoclonal IgA deposits has not been described previously.

An Integrated Memory Array Processor Architecture for Embedded Image Recognition Systems

Embedded processors for video image recognition require to address both the cost (die size and power) versus real-time performance issue, and also to achieve high flexibility due to the immense diversity of recognition targets, situations, and applications. This paper describes IMAP, a highly parallel SIMD linear processor and memory array architecture that addresses these trading-off requirements. By using parallel and systolic algorithmic techniques, despite of its simple architecture IMAP achieves to exploit not only the straightforward per image row data level parallelism (DLP), but also the inherent DLP of other memory access patterns frequently found in various image recognition tasks, under the use of an explicit parallel C language (1DC). We describe and evaluate IMAP-CE, a latest IMAP processor, which integrates 128 of 100MHz 8 bit4-way VLIW PEs, 128 of 2KByte RAMs, and one 16 bit RISC control processor, into a single chip. The PE instruction set is enhanced for supporting 1DC codes. IMAP-CE is evaluated mainly by comparing its performance running 1DC codes with that of a 2.4GHz Intel P4 running optimized C codes. Based on the use of parallelizing techniques, benchmark results show a speedup of up to 20 for image filter kernels, and of 4 for a full image recognition application.

Concurrent opposite effects of trichostatin A, an inhibitor of histone deacetylases, on expression of alpha-MHC and cardiac tubulins: implication for gain in cardiac muscle contractility.

Histone deacetylases (HDACs) are a family of enzymes that catalyze the removal of acetyl groups from core histones, resulting in change of chromatin structure and gene transcription activity. In the heart, HDACs are targets of hypertrophic signaling, and their nonspecific inhibition by trichostatin A (TSA) attenuates hypertrophy of cultured cardiac myocytes. In this study, we examined the effect of TSA on two major determinants of cardiac contractility: alpha-myosin heavy chain (MHC) expression and microtubular composition and organization. TSA upregulated the expression of alpha-MHC in cultured cardiac myocytes, as well as in an in vivo model of hypothyroid rats. Studies designed to delineate mechanisms of alpha-MHC induction by TSA revealed an obligatory role of early growth response factor-1 on activation of the alpha-MHC promoter. Concurrently, TSA downregulated the expression of alpha- and beta-tubulins and prevented the induction of tubulins by a hypertrophy agonist, ANG II. The ANG II-mediated increased proportion of alpha- and beta-tubulins associated with polymerized microtubules was also markedly reduced after treatment of cells by TSA. Results obtained from immunofluorescent microscopy indicated that TSA had no noticeable effect on the organization of cardiac microtubules in control cells, whereas it prevented the ANG II-induced dense parallel linear arrays of microtubules to a profile similar to that of controls. Together, these results demonstrate that inhibition of HDACs by TSA regulates the cardiac alpha-MHC and tubulins in a manner predictive of improved cardiac contractile function. These studies improve our understanding of the role of HDACs on cardiac hypertrophy with implications in development of new therapeutic agents for treatment of cardiac abnormalities.

Floquet wave-based diffraction approach for irregularly contoured planar phased arrays

A uniform high-frequency formulation of the Green's function is presented, for an arbitrarily contoured finite array of electric dipoles. The planar array is thought of as a sequence of parallel finite linear arrays. Its field is obtained by numerical superposition of the dominant field contributions from each constituent linear array. These contributions are uniformly asymptotically evaluated to yield a field representation in terms of truncated single-indexed conical Floquet waves and tip-diffracted spherical waves. Superimposing the linear array asymptotic contributions leads to a convenient description of the total radiated field at finite distance from the planar array. This is represented as the sum of diffracted fields arising from the actual rim plus conical waves from points located along a curved line on the array surface. The final expression is simple, physically appealing, and more efficient than the element-by-element summation, as demonstrated by numerical examples.

Energy transfer in nanostructured oligothiophene inclusion compounds

Resonant energy transfers from terthiophene (T3) to quinquethiophene (T5) oligomers embedded in the nanochannels of perhydrotriphenylene (PHTP) crystals are studied by cw and femtosecond spectroscopy. The stringent geometry imposed by the host results in a very peculiar supramolecular organization of the guest molecules consisting of parallel linear arrays of chromophores. This provides a unique opportunity to make a quantitative analysis of the energy transfer phenomena and in particular to distinguish between heterotransfers and homotransfers. The experimental data fitted by a suitable theoretical analysis indicate that homotransfers become important in the long time dynamics and that the heterotransfer rate is satisfactorily described by the analytical solution obtained by assuming a continuous intermolecular spacing.