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排序方式: 共有1827条查询结果,搜索用时 375 毫秒
51.
Controlling Synergistic Oxidation Processes for Efficient and Stable Blue Thermally Activated Delayed Fluorescence Devices
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52.
Blue OLEDs: Controlling Synergistic Oxidation Processes for Efficient and Stable Blue Thermally Activated Delayed Fluorescence Devices (Adv. Mater. 35/2016)
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53.
Outdoor autonomous navigation using SURF features 总被引:1,自引:0,他引:1
In this article, we propose a speeded-up robust features (SURF)-based approach for outdoor autonomous navigation. In this
approach, we capture environmental images using an omni-directional camera and extract features of these images using SURF.
We treat these features as landmarks to estimate a robot’s self-location and direction of motion. SURF features are invariant
under scale changes and rotation, and are robust under image noise, changes in light conditions, and changes of viewpoint.
Therefore, SURF features are appropriate for the self-location estimation and navigation of a robot. The mobile robot navigation
method consists of two modes, the teaching mode and the navigation mode. In the teaching mode, we teach a navigation course.
In the navigation mode, the mobile robot navigates along the teaching course autonomously. In our experiment, the outdoor
teaching course was about 150 m long, the average speed was 2.9 km/h, and the maximum trajectory error was 3.3 m. The processing
time of SURF was several times shorter than that of scale-invariant feature transform (SIFT). Therefore, the navigation speed
of the mobile robot was similar to the walking speed of a person. 相似文献
54.
In this paper, we present various linear analyses of the linearized lateral dynamics of heavy‐duty vehicles (HDVs) (tractor‐semitrailer type), which include time domain, frequency domain and pole/zero analyses. These analyses are conducted to examine the vehicle response to the steering input subjected to variations of speed, road adhesion coefficient, cargo load in the trailer, and look‐ahead distance for the lateral deviation sensor. These parameters (uncertainties) have significant influence on vehicle dynamics. It has been shown that redefining the look‐ahead lateral error as the controlled output has a favorable impact on the lateral control problem. Based on these analyses, a robust steering controller using H∞ loop‐shaping procedure is designed for a tractor semitrailer combination to follow the road center line on both curved and straight highway sections. The proposed controller ensures the robust performance under model uncertainties which include varying vehicle longitudinal speed, road adhesion coefficient, and cargo load in the trailer. The performance of the designed controller is evaluated by simulations and validated by experiments. 相似文献
55.
Yoshihiro Adachi Kensei Tsuchida Takanori Imaki Takeo Yaku 《Electronic Notes in Theoretical Computer Science》2000,30(4):276-288
An intelligible program diagram called Logichart has been developed for Prolog visualization. Its syntax rules and layout rules are formalized in terms of an attribute graph grammar. This grammar is underlain by a context–free graph grammar whose productions are defined to formalize the graph–syntax rules of Logichart diagrams. Semantic rules attached to the productions are defined in such a way that they can extract the layout information needed to display a Logichart diagram as attributes. Our Prolog visualization system, which has been implemented based on the attribute graph grammar, can draw a Logichart diagram for any correct Prolog program (completeness), and any Logichart diagram displayed by the system is always valid for the grammar (soundness). The system can also display the execution of a Prolog program in real time; that is, the Logichart diagram is dynamically updated as the program runs. 相似文献
56.
57.
Shunjiro Ogawa Hideyo Suzuki Masatake Toyoda Yoshio Ito Masahiro Iwaida Hiroko Nonogi Tazu Fuke Kazuo Obara Tadao Adachi Koichi Fujita Makiko Ikuzawa Tetsuo Izumi Takashi Hamano Yukimasa Mitsuhashi Yukio Matsuki 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1979,168(4):293-298
Summary Detection and determination of traces of sulphites in foods was attempted by use of the modified Rankine apparatus and pararosaniline colorimetry. Replacement of alkaline titration reported previously by pararosaniline colorimetry lowered the absolute detection limit from 30 g (titration method) to 2 g. In view of clean analysis, in the color developing system, 0.1 N-sodium hydroxide was used in place of mercuric chloride solution commonly used as an absorbant of sulphites. In order to prevent oxidative decomposition of sulphites during operation, nitrogen gas was used as carrier instead of air. Dimedone and sodium azide were used for the elimination of aldehydes and nitrites, respecitvely, in the sample, which will disturb the color development of sulphites with pararosaniline-formaldehyde reagents. With this improved method, it was possible to determine the residual sulphites in frozen peeled shrimps, sugared beans and other foods with low sulphite contents accurately.
Studies on the Analyses of Sulphites in Foods (IV) 相似文献
Colorimetrische Mikrobestimmung von Sulfiten in Lebensmitteln bei Anwendung der modifizierten IV. Rankine Apparatur
Zusammenfassung Geringe Sulfitmengen in Lebensmitteln (geschälte Garnelen, gezuckerte Bohnen) können colorimetrisch bestimmt werden. Die neuentwickelte Methode beruht auf einer Kombination von colorimetrischer Bestimmung mittels p-Rosanilin und der Bestimmungsmethode nach Rankine. Auf diese Weise lassen sich Gehalte von 2 g noch genau bestimmen. Bei der Farbentwicklung wurde das giftige Quecksilbertetrachlorid durch 0.1 n-NaOH ersetzt, anstelle von Luft Stickstoff als Trägergas verwendet und somit eine Oxydation des Sulfits während der Bestimmung vermieden. Da Nitrit und Aldehyde die Farbentwicklung stören, wurde ihr Einfluß durch Dimedon und Natriumazid ausgeschaltet.
Studies on the Analyses of Sulphites in Foods (IV) 相似文献
58.
Kato K. Kurimoto M. Shumiya H. Adachi H. Sakuma S. Okubo H. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2006,13(2):362-372
Functionally graded materials (FGM) have spatial distribution of a material property in order to achieve efficient stress control. An application of the FGM to a solid insulator (spacer) for a gaseous insulation system, like gas insulated switchgear, is expected to improve electric field (E-field) distribution around the spacer. In this paper, we describe the applicability of the FGM spacer to gas insulated power equipment. In the FGM spacer, we gave spatial distribution of dielectric permittivity to control the E-field distribution inside and outside the spacer. This paper includes following key results for the applications of the FGM. Firstly, E-field simulation results when applying the FGM by a finite element method are presented, in which we show the effective reduction of the maximum field strength by applying the FGM. Next, a fabrication technique of the FGM spacer sample with not only step-by-step but also continuous changes of permittivity is presented by use of centrifugal force. Finally, dielectric breakdown tests using FGM samples which are accurately controlled the spatial distribution of permittivity are carried out under lightning impulse voltage applications. The test result indicates the increase of breakdown voltage (BDV). From these results, we verified the applicability and the fabrication technique of FGM spacer for improvement of the dielectric strength in the gaseous insulation system. 相似文献
59.
Spacing loss due to micro-waviness and curvature effects in the radial direction of a disk was investigated via numerical simulations and measurements. New techniques based on interferometry and laser scanning were employed to measure radius of curvature (ROC) and to reconstruct the profiles at the outer edge of a disk. A good correlation between ROC values and fly height degradation was obtained, and ROC less than 50 m clearly showed the deterioration in fly height by as much as 1.5 nm. The new measurement techniques proved to be an important means to improve substrate manufacturing processes. 相似文献
60.
基于微放电加工元件轮廓测量的探针制造 总被引:1,自引:0,他引:1
KAWADAMasayoshi MITSUIKimiyuki 《纳米技术与精密工程》2004,2(2):124-131
为了推动微加工和微机械技术的进步,微型零件轮廓和尺度测量方法的发展非常重要.可行方法之一就是使用带微探头的小型三维轮廓测量仪.这种仪器的探头必须针对某个零件的测量,按照最佳外形制造.微放电加工有着极小加工力,可用于各种探头的制造,本研究中用它进行探头加工.用这种方法制造了多种探头,将其装在基于扫瞄隧道显微技术(STM)的小型三维轮廓测量仪上.所制造的探头已被成功地用于各种微元件测量,结果表明此方法可行. 相似文献