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1.
Platforms like gantries, booms, aircrafts, and submersibles are often used in the broadcasting industry. To avoid collisions and occlusions, such mechatronic platforms often possess redundant degrees-of-freedom (DOFs). As a result, manual manipulating of such platforms demands much skill. This paper describes the implementation of several controllers that, by using computer vision, attempts to reduce the number of manually manipulated DOFs. Experiments were performed to assess the performance of each controller. A model for such a system was developed and validated. To determine how the visual servoing can improve the tracking, a novice operator and an expert were asked to manually track a moving target with the assistance of visual servoing. The results of these tests were analyzed and compared  相似文献   
2.
Focused ultrasound is very well suited for inducing noninvasive local hyperthermia. Since magnetic resonance imaging (MRI) may be employed to obtain real-time temperature maps noninvasively the combination of these two technologies offers great advantages specifically aimed toward oncological studies. Real-time identification of the target region and accurate control of the temperature evolution during the treatment has now become possible. Thermal ablation of pathological tissue, local drug delivery using thermosensitive micro-carriers and controlled transgene expression using thermosensitive promoters have recently been demonstrated with this unique technology. Based on these experiments combined focused ultrasound and MRI thermometry holds promise for future oncological diagnostics and treatment. In this paper, we review some of the recent methodological developments as well as experimental and first clinical studies using this approach.  相似文献   
3.
Students are nowadays given many options to consume educational content in digital formats as alternatives to printed material. Previous research suggests that while digital content has advantages, printed media still provides other benefits that cannot be matched by digital. Therefore, technology should leverage the benefits of both. In this paper, we present the Meaningful Education and Training Information System, a multifaceted hybrid textbook learning platform. The goal of the system is to provide an easy digital‐to‐print‐to‐digital content creation and reading service. The Meaningful Education and Training Information System incorporates technologies for layout, personalization, cocreation, and assessments. These facilitate common teacher/student tasks and help provide a richer, more effective learning experience. Our system has been demonstrated in multiple international education events, partner engagements, and pilots with local universities and high schools.  相似文献   
4.
Many database applications have the emerging need to support approximate queries that ask for strings that are similar to a given string, such as “name similar to smith” and “telephone number similar to 412-0964”. Query optimization needs the selectivity of such an approximate predicate, i.e., the fraction of records in the database that satisfy the condition. In this paper, we study the problem of estimating selectivities of approximate string predicates. We develop a novel technique, called Sepia, to solve the problem. Given a bag of strings, our technique groups the strings into clusters, builds a histogram structure for each cluster, and constructs a global histogram. It is based on the following intuition: given a query string q, a preselected string p in a cluster, and a string s in the cluster, based on the proximity between q and p, and the proximity between p and s, we can obtain a probability distribution from a global histogram about the similarity between q and s. We give a full specification of the technique using the edit distance metric. We study challenges in adopting this technique, including how to construct the histogram structures, how to use them to do selectivity estimation, and how to alleviate the effect of non-uniform errors in the estimation. We discuss how to extend the techniques to other similarity functions. Our extensive experiments on real data sets show that this technique can accurately estimate selectivities of approximate string predicates. A short version of this article appeared as [21] in the proceedings of the 31st International Conference on Very Large Data Bases (VLDB), August 30 – September 2, 2005, Trondheim, Norway. The source code of our algorithms is available at .  相似文献   
5.
Context: Near-Infrared (NIR) spectroscopy is an important component of a Process Analytical Technology (PAT) toolbox and is a key technology for enabling the rapid analysis of pharmaceutical tablets.

Objective: The aim of this research work was to develop and validate NIR-chemometric methods not only for the determination of active pharmaceutical ingredients content but also pharmaceutical properties (crushing strength, disintegration time) of meloxicam tablets.

Materials and methods: The development of the method for active content assay was performed on samples corresponding to 80%, 90%, 100%, 110% and 120% of meloxicam content and the development of the methods for pharmaceutical characterization was performed on samples prepared at seven different compression forces (ranging from 7 to 45?kN) using NIR transmission spectra of intact tablets and PLS as a regression method.

Results: The results show that the developed methods have good trueness, precision and accuracy and are appropriate for direct active content assay in tablets (ranging from 12 to 18 mg/tablet) and also for predicting crushing strength and disintegration time of intact meloxicam tablets.

Discussion: The comparative data show that the proposed methods are in good agreement with the reference methods currently used for the characterization of meloxicam tablets (HPLC-UV methods for the assay and European Pharmacopeia methods for determining the crushing strength and disintegration time).

Conclusion: The results show the possibility to predict both chemical properties (active content) and physical/pharmaceutical properties (crushing strength and disintegration time) directly, without any sample preparation, from the same NIR transmission spectrum of meloxicam tablets.  相似文献   
6.
ASTERIX is a new data-intensive storage and computing platform project spanning UC Irvine, UC Riverside, and UC San Diego. In this paper we provide an overview of the ASTERIX project, starting with its main goal—the storage and analysis of data pertaining to evolving-world models. We describe the requirements and associated challenges, and explain how the project is addressing them. We provide a technical overview of ASTERIX, covering its architecture, its user model for data and queries, and its approach to scalable query processing and data management. ASTERIX utilizes a new scalable runtime computational platform called Hyracks that is also discussed at an overview level; we have recently made Hyracks available in open source for use by other interested parties. We also relate our work on ASTERIX to the current state of the art and describe the research challenges that we are currently tackling as well as those that lie ahead.  相似文献   
7.
The effects of the self-assembled layers formed by adsorption of 4,4′-thio-bis-benzenethiol from ethanol solutions on p-Si(1 1 1) and p-GaAs(1 0 0) electrodes were examined by EIS, AFM and XPS investigations. All the experimental data led to the conclusion that the thio-bis-benzenethiolate film spontaneously formed on Si and GaAs surfaces brings about chemical passivation, both in air and in solution, as well as strong adsorbate-substrate interactions which affect the semiconductor surface state population and the field effects operating in the interfacial region. Semiempirical PM3 molecular orbital calculations showed that electronic interaction of the thiolate film with the two semiconducting electrodes can be understood in terms of changes in the local density of the electronic states at the surface.  相似文献   
8.
Structural investigation of xFe2O3·(100 − x)[3B2O3·SrO] glass system, with 0 ≤ x ≤ 40 mol%, was performed by means of X-Ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopies. The purpose of this work was to investigate the structural changes that appear in the 3B2O3·SrO glass matrix with the addition and increasing of iron ions content. The XRD pattern for the prepared samples shows that vitreous phase is present only for x ≤ 40 mol%. For sample containing 50 mol% Fe2O3 was evidenced the presence of a unique crystalline phase, Fe2O3, embedded in an amorphous matrix. FTIR data show that BO3 and BO4 are the main structural units of the glass system and the iron ions are located in the network. The Raman spectrum of glass matrix indicates a structure with several borate groups (di-, meta-, pyro-borate, etc.). In higher concentrations the iron ions break the regulate glass network and determines the appearance of BO4 isolated units.  相似文献   
9.

Introduction  

The susceptibility contrast between frozen and unfrozen tissue disturbs the local magnetic field in the proximity of the ice-ball during cryotherapy. This effect should be corrected for in real time to allow PRFS-based monitoring of near-zero temperatures during intervention.  相似文献   
10.
ITO thin films deposited by advanced pulsed laser deposition   总被引:1,自引:0,他引:1  
Indium tin oxide thin films were deposited by computer assisted advanced PLD method in order to obtain transparent, conductive and homogeneous films on a large area. The films were deposited on glass substrates. We studied the influence of the temperature (room temperature (RT)-180 °C), pressure (1-6 × 10− 2 Torr), laser fluence (1-4 J/cm2) and wavelength (266-355 nm) on the film properties. The deposition rate, roughness, film structure, optical transmission, electrical conductivity measurements were done. We deposited uniform ITO thin films (thickness 100-600 nm, roughness 5-10 nm) between RT and 180 °C on a large area (5 × 5 cm2). The films have electrical resistivity of 8 × 10− 4 Ω cm at RT, 5 × 10− 4 Ω cm at 180 °C and an optical transmission in the visible range, around 89%.  相似文献   
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