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991.
992.
Il Young Song Ju Hong Yoon Seung Hwan Bae Moongu Jeon 《International journal of remote sensing》2013,34(18):5746-5767
In this article, we classify road surface statuses using a Bayesian classification method. This article uses principal component analysis (PCA) that combines a 94 GHz dual-channel polarimetric radiometer. The radiometer is used to investigate the behaviour of the brightness temperature (BT) of different road surface statuses in an open-air laboratory. The aim of this investigation is to characterize four different road surface classes (dry, wet, snowy and icy). Here, the BT (radiothermal emission) characteristics are measured at horizontal and vertical polarizations. For a given database of weather information (including BT, road surface temperature, wind speed, etc.), a PCA subspace is constructed, and the score vectors are classified by solving the Bayesian classification method. As a result, the road surface statuses were found to be well classified by the proposed method in real time. 相似文献
993.
It is more important to properly handle exceptions, than to prevent exceptions from occurring, because they arise from so many different causes. In embedded systems, a vast number of exceptions are caused by hardware devices. In such cases, numerous software components are involved in these hardware device-originated exceptions, ranging from the device itself to the device driver, the kernel, and applications. Therefore, it takes a lot of time to debug software that fails to handle exceptions. This paper proposes a lightweight device exception testing method, and a related automation tool, AMOS v3.0. The proposed method artificially triggers more realistic device exceptions in runtime, and monitors how software components handle exceptions in detail. AMOS v3.0 has been applied to the exception testing of car-infotainment systems in an automobile company. The results based on this industrial field study have revealed that 39.13% of the failures in exception handling were caused by applications, 36.23% of the failures were caused by device drivers, and 24.64% were derived from the kernel. We conclude that the proposed method is highly effective, in that it can allow developers to identify the root cause of failure for exception handling. 相似文献
994.
An output feedback tracking controller is proposed for single-input, single-output non-linear systems that are diffeomorphic to the non-linear observer form. Difficulty in obtaining the output injection terms of the non-linear observer form is solved by a numerical technique and the interpolation method using the radial basis function (RBF) network. The trained RBF networks approximate output injection terms in a compact interval and are utilized for building a non-linear observer. In constructing the output tracking controller the backstepping control method is adopted based on the state estimates. 相似文献
995.
In this paper, a new framework of a two loop disturbance rejection control and its design methodology are proposed. The framework consists of a robust internal-loop compensator (RIC) to eliminate disturbances and an external-loop controller to achieve nominal control performance. As the main contribution of this paper, we define the design problem of the RIC as a regulation control problem, then show that this new definition with the RIC structure provides more design flexibility and less implementation constraints, which allows us to design the RIC aggressively against a specific disturbance. This is verified through a comparative structural analysis with a disturbance observer (DOB) and an adaptive robust control (ARC). Two design examples of the RIC are given, along with practical issues that should be considered in the design procedure. The proposed framework is demonstrated by simulations and experiments. 相似文献
996.
A simple and conventional PECVD method was adopted to synthesize scratch-resistant hydrophobic and oleophobic films, by varying the process condition. The film was designed to be 3 layered. The first SiOx layer was coated on the substrate using OMCTS and O2, followed by O2 plasma treatment; hydrocarbon-based hydrophobic film was synthesized using HMDS as a second layer; and finally, CFx-based film was coated using C2F6. The first and second layers were synthesized using RF power of 13.56 MHz, while MF power of 40 kHz was used for the CFx layer for ion-assisted deposition. The water contact angle was measured to be 110°–115°, and the oil contact angle was 84° for the best obtained sample. The pencil hardness was measured to be 7H for anti-scratch property. XPS was adopted to analyze the chemical structure and showed that highly cross-linked dense structured film was synthesized. 相似文献
997.
998.
ABSTRACT In this paper, fully embedded dual-band WLAN diplexer, 2.4 GHz WLAN BPF and wide-band pass filter are investigated into a multi-layered organic package substrate for low cost RF SOP (System on Package) applications. These embedded passive components were designed and analyzed by using ADS circuit simulator and CST 3D EM simulator for verifying their applicability. The fabricated diplexer and filters are the smallest one of the filters formed onto the organic substrate. The diplexer has a size of 3 mm × 2.5 mm × 0.77 mm and exhibits an insertion loss of max ?0.68 dB in 2.4 ~ 2.5 GHz band and max –3 dB in 5.15 ~ 5.32 GHz band, respectively. The 2.4 GHz BPF has a size of 2.7 mm × 2.1 mm × 0.77 mm and exhibits an insertion loss of max ?2.7 dB. The WBPF has a size of 3.2 mm × 2.5 mm × 0.77 mm and exhibits an insertion loss of ?2.65 dB. The major benefit of these embedded passive components, compared to a discrete solution, is a significant simplification and size/volume reduction of RF systems design. 相似文献
999.
A silane–cerium treatment was applied on an aluminum adherend to simultaneously improve the bonding performance and corrosion resistance of the adhesively bonded aluminum joint in cryogenic applications, such as with liquefied natural gas containment tanks. The lap shear strengths and corrosion performances of the adhesively bonded joints composed of treated aluminum adherends were measured with respect to the silane–cerium treatment and the surface pretreatment on the aluminum adherend. The bonding characteristics of the aluminum adherend were investigated by measuring the water contact angle and conducting the potentiodynamic polarization test after the aluminum adherends with different surface treatments of silane–cerium were immersed in a 0.5?M NaCl solution. In addition, the surfaces were analyzed with scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy to characterize the chemical compositions of the silane–cerium-treated aluminum adherend. The experimental results show that an appropriate silane–cerium treatment on the aluminum adherend produces an effective corrosion-resistant layer and that it has a highly reliable bonding characteristic for the adhesive joint at a cryogenic temperature of ?150?°C. 相似文献
1000.
The recovery behaviors of vulcanized natural rubber from circular deformation were studied by varying sample length to investigate the influence of the degree of applied strain to the sample. The stress and strain varied uniformly across the thickness of the sample, and the degree of applied stress and strain to the sample decreased with increasing the sample length. The linear sample was made into a circular form and thermally aged in a convection oven. The recovery was measured after removing from the circular deformation. The recovery increased by decreasing the sample length. The difference in recoveries of the samples with different lengths reduced at high temperature. The short sample had higher heat‐resisting property for recovery than the long sample. The experimental results were explained by the rearrangement and stabilization of the deformed rubber chains as well as the crosslink density change. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献