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1.
Serie建筑师事务所是一个国际化事务所,涉及的领域包括建筑、城市的设计。事务所关注于当代城市中建筑类型的进化和变异以及这些智慧形式在空间解决方案上的应用。类型学式的研究,或者用他们的名词,“连续”(SERIES)的思考和探索(利用建筑类型的累积智慧)是Serie作品的关键。  相似文献   
2.
Intramedullary spinal cord tumors are a rare and understudied cancer with poor treatment options and prognosis. Our prior study used a combination of PDGF-B, HRAS, and p53 knockdown to induce the development of high-grade glioma in the spinal cords of minipigs. In this study, we evaluate the ability of each vector alone and combinations of vectors to produce high-grade spinal cord gliomas. Eight groups of rats (n = 8/group) underwent thoracolumbar laminectomy and injection of lentiviral vector in the lateral white matter of the spinal cord. Each group received a different combination of lentiviral vectors expressing PDGF-B, a constitutively active HRAS mutant, or shRNA targeting p53, or a control vector. All animals were monitored once per week for clinical deficits for 98 days. Tissues were harvested and analyzed using hematoxylin and eosin (H&E) and immunohistochemical (IHC) staining. Rats injected with PDGF-B+HRAS+sh-p53 (triple cocktail) exhibited statistically significant declines in all behavioral measures (Basso Beattie Bresnahan scoring, Tarlov scoring, weight, and survival rate) over time when compared to the control. Histologically, all groups except the control and those injected with sh-p53 displayed the development of tumors at the injection site, although there were differences in the rate of tumor growth and the histopathological features of the lesions between groups. Examination of immunohistochemistry revealed rats receiving triple cocktail displayed the largest and most significant increase in the Ki67 proliferation index and GFAP positivity than any other group. PDGF-B+HRAS also displayed a significant increase in the Ki67 proliferation index. Rats receiving PDGF-B alone and PDGF-B+ sh-p53 displayed more a significant increase in SOX2-positive staining than in any other group. We found that different vector combinations produced differing high-grade glioma models in rodents. The combination of all three vectors produced a model of high-grade glioma more efficiently and aggressively with respect to behavioral, physiological, and histological characteristics than the rest of the vector combinations. Thus, the present rat model of spinal cord glioma may potentially be used to evaluate therapeutic strategies in the future.  相似文献   
3.
The present paper reports constrained optimization of explicit Runge–Kutta (RK) schemes, coupled with optimal upwind compact scheme to achieve dispersion relation preservation (DRP) property for high performance computing. Essential ideas of optimization employed in arriving at the proposed time integration scheme are extension of the earlier work reported in Rajpoot et al. (J Comput Phys 2010;229:3623–51). This is in turn an application of the correct error evolution equation in Sengupta et al. (J Comput Phys 2007;226:1211–8). Resultant DRP scheme demonstrated the idea for explicit spatial central difference schemes. Present work is similar, extending it for near-spectral accuracy compact schemes. Practical utility of the developed method is demonstrated by solution of model problems and for flow problems by solving Navier–Stokes equation, some of which cannot be solved by conventional schemes, as the problem of rotary oscillation of cylinder.Developed method is calibrated with: (i) flow past a circular cylinder performing rotary oscillation at Re = 150 and (ii) flow inside a 2D lid-driven cavity (LDC) at Reynolds numbers of Re = 1000 and Re = 10,000. Quantitative and qualitative comparisons show excellent match for rotary oscillation cylinder cases with the experimental results of Thiria et al. (J Fluid Mech 2006;560:123–47). Results for LDC for Re = 1000 are compared with that in Botella & Peyret (Comp Fluids 1998;27:421–33) and results for Re = 10,000 are compared with recent published ones showing triangular vortex in the core.  相似文献   
4.
Three-dimensional reconstruction of large tissue volumes using histological thin sections poses difficulties because of registration of sections, section distortion, and the possibility of incomplete data set collection due to section loss. We have constructed an integrated surface imaging system that successfully addresses these problems. Embedded tissue is mounted on a high precision XYZ stage and the upper surface is iteratively: (i) stained to provide an effective optical section, (ii) imaged using a digital camera, and (iii) removed with an ultramiller. This approach provides for the reconstruction of high-quality 3D images by inherently preserving image registration, eliminates section distortion, thus removing the need for complex realignment and correction, and also ensures full capture of all image planes. The system has the capacity to acquire images of tissue structure with voxel sizes from 0.5 to 50 mum over dimensions ranging from micrometers to tens of millimeters. The ultramiller enables large samples to be imaged by reliably removing tissue over their full extent. The ability to visualize key features of 3D tissue structure across such a range of scale and resolution will facilitate the development of a greater understanding of the relationship between structure and function. This understanding is essential for better analyses of the structural changes associated with different disease states, and the development of structure-based computer models of biological function.  相似文献   
5.
Methoxy(polyethylene glycol)-maleimide (mPEG-mal) is a PEG derivative used for thiol PEGylation of protein molecules and finds application in drug delivery studies. The maleimide group undergoes degradation in aqueous media, resulting in the difficult quantitative analysis of mPEG-mal. Routinely employed methods for separation and estimation of mPEG-mal include tedious chromatographic methods like ion exchange, high-performance liquid chromatography with refractive index detector and techniques like mass spectrometry and proton nuclear magnetic resonance. We present a direct and reproducible spectrophotometric method to quantify free and protein bound mPEG-mal in thiol PEGylation reaction mixtures. This method is based on the partitioning of a PEG bound chromophore between an aqueous ammonium isoferrothiocyanate phase to a chloroform phase in the presence of mPEG-mal. Several important parameters influencing the partitioning and stability of the chromophore, volume ratios of liquid phases, ethylenediaminetetraacetic acid concentration in the reaction mixture, mixing time, and chlorinated solvents used for partitioning have been studied.  相似文献   
6.
Spatial filters have been rigorously analyzed here for stabilization and dispersion relation preservation properties using spectral-matrix theory.Traditional LES faces problems of instability, aliasing and additional complexity of SGS modeling. Here, an alternative is proposed where unfiltered governing equation is solved, followed by spatial upwind filtering, without requiring any SGS models. This filter retains the resolution of high accuracy methods and removes energy, like the action of hyper-viscosity used in spectral methods. As examples, solutions for (a) accelerated flow past a NACA-0015 airfoil held normal to the flow and (b) transitional flow past a NLF airfoil, have been reported.  相似文献   
7.
The performance of wireless communication systems is predominantly dependent on propagation environment and respective radiating antennas. Due to the shorter wavelength at millimeter wave (MmW) frequencies, the propagation loss through the objects in indoor environments is typically very high. To improve the channel capacity and to reduce inter-user interference, a high gain directional antenna is desired at MmW frequencies. Traditional antennas used in MmW devices are not suitable for low-cost commercial devices due to their heavy and bulky configurations. This paper focuses on design and development of a very compact (44.61?×?9.93?×?0.381 mm) high gain antipodal linear tapered slot antenna (ALTSA) utilizing substrate integrated waveguide (SIW) technology at 60 GHz. Received signal strength (RSS), path loss, and capacity are studied for MmW indoor applications utilizing ALTSA with radio frequency (RF) measurement equipment in narrow hallway environment.  相似文献   
8.
Electrokinetic instabilities have been extensively studied in microchannel fluid flows with conductivity or conductivity and permittivity gradients for various microfluidic applications. This work presents an experimental and numerical investigation of the electrokinetic co-flow of ferrofluid and buffer solutions with matched electric conductivities. We find that the ferrofluid and buffer interface becomes unstable with periodic waves if the applied direct-current electric field reaches a threshold value. We develop a two-dimensional numerical model to seek a preliminary understanding of such an electrically originated flow instability. Our model indicates that the observed phenomenon is not a consequence of the electric body force acting on the permittivity gradients between the ferrofluid and buffer solutions. It is instead attributed to the diffusion-induced conductivity gradients that are formed at the ferrofluid and buffer interface due to the mismatching diffusivities of ferrofluid nanoparticles and buffer ions.  相似文献   
9.
In the present work, a new class of explicit two-dimensional filter is proposed that is significantly different from the conventional one-dimensional Padè type filters. Comparison of performance between one- and two-dimensional filters are made in studying propagation problems and actual viscous flow problems. In this preliminary work, the focus is kept solely on developing central filters with its real transfer function. Many applications related to Navier–Stokes equation have been shown to demonstrate that these two-dimensional filters help in numerical stabilization; control aliasing and control over spurious upstream propagating disturbances. Furthermore, its potential for large eddy simulation (LES) is suggested by band-limiting the solution via filters in post-processing mode.  相似文献   
10.
Metasurfaces control various properties of light via scattering across a large number of subwavelength‐spaced nanostructures. Although metasurfaces appear to be ideal photonic platforms for realizing and designing miniaturized devices, their chromatic aberrations have hindered the large‐scale deployment of this technology in numerous applications. Wavelength‐dependent diffraction and resonant scattering effects usually limit their working operation wavelengths. In refractive optics, chromatic dispersion is a significant problem and is generally treated by cascading multiple lenses into achromatic doublets, triplets, and so on. Recently, broadband achromatic metalenses in the visible have been proposed to circumvent chromatic aberration but their throughput efficiency is still limited. Here, the dispersion of refractive components is corrected by leveraging the inherent dispersion of metasurfaces. Hybrid refractive‐metasurface devices, with nondispersive refraction in the visible, are experimentally demonstrated. The dispersion of this hybrid component, characterized by using a Fourier plane imaging microscopy setup, is essentially achromatic over about 150 nm in the visible. Broadband focusing with composite plano‐convex metasurface lenses is also proposed. These devices could find applications in numerous consumer optics, augmented reality components, and all applications including imaging for which monochromatic performance is not sufficient.  相似文献   
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