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1.
Induction based fluidics (IBF), a new, simple patented approach for transporting liquids in the micro and the macro world, is discussed. Electric fields are shown to energize liquid/s in a container/s to execute an array of purposes. IBF is shown uniquely to energize N liquids in simple off the shelf devices, inductively. We discuss calibration and other issues, as we demonstrate how simple devices can dispense nanoliters and microliters with high precision and accuracy. Furthermore, we show preliminary single and eight channel data for the Zip Tip™ made by Millipore where the device transports liquids “electrically.” We briefly consider how such new devices, “electric” Zip Tips™, might automate desalting and the placement of digests for MALDI TOF analysis.  相似文献   

2.
The threat of cyber attacks motivates the need to monitor Internet traffic data for potentially abnormal behavior. Due to the enormous volumes of such data, statistical process monitoring tools, such as those traditionally used on data in the product manufacturing arena, are inadequate. “Exotic” data may indicate a potential attack; detecting such data requires a characterization of “typical” data. We devise some new graphical displays, including a “skyline plot,” that permit ready visual identification of unusual Internet traffic patterns in “streaming” data, and use appropriate statistical measures to help identify potential cyberattacks. These methods are illustrated on a moderate-sized data set (135,605 records) collected at George Mason University.  相似文献   

3.
High throughput parallel organic synthesis is now a common practice in discovery chemistry research. Argonaut's modular reaction cassette technology is aimed at parallel synthesis of focused small molecule libraries. The Trident™ automated platform has been designed to perform high throughput organic synthesis using this modular reaction cassette under truly inert conditions and in a robust, reproducible manner. This enables one to generate high quality libraries of small molecules and to access chemistry not normally amenable to automation.Recently we have introduced a Sample Processing Station (SPS), which enhances the upstream and downstream sample handling capabilities of the Trident™ platform. Enhanced software capabilities also provide the Trident™ synthesizer with powerful reaction development and optimization capabilities. Application of this technology in the synthesis of a small library of 1,2-diarylbenzimidazoles using solution-phase chemistry is presented. A number of product purification and isolation protocols using polymer-bound scavengers are discussed.  相似文献   

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Consider a binary image containing one or more objects. A signed distance transform assigns to each pixel (voxel, etc.), both inside and outside of any objects, the minimum distance from that pixel to the nearest pixel on the border of an object. By convention, the sign of the assigned distance value indicates whether or not the point is within some object (positive) or outside of all objects (negative). Over the years, many different algorithms have been proposed to calculate the distance transform of an image. These algorithms often trade accuracy for efficiency, exhibit varying degrees of conceptual complexity, and some require parallel processors. One algorithm in particular, the Chamfer distance [J. ACM 15 (1968) 600, Comput. Vis. Graph. Image Process. 34 (1986) 344], has been analyzed for accuracy, is relatively efficient, requires no special computing hardware, and is conceptually straightforward. It is understandably, therefore, quite popular and widely used. We present a straightforward modification to the Chamfer distance transform algorithm that allows it to produce more accurate results without increasing the window size. We call this new algorithm Dead Reckoning as it is loosely based on the concept of continual measurements and course correction that was employed by ocean going vessel navigation in the past. We compare Dead Reckoning with a wide variety of other distance transform algorithms based on the Chamfer distance algorithm for both accuracy and speed, and demonstrate that Dead Reckoning produces more accurate results with comparable efficiency.  相似文献   

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By manipulating the imaginary part of the complex-analytic quadratic equation, we obtain, by iteration, a set that we call the “burning ship” because of its appearance. It is an analogue to the Mandelbrot set (M-set). Its nonanalytic “quasi”-Julia sets yield surprizing graphical shapes.  相似文献   

8.
This study explores whether in the absence of face‐to‐face interaction individuals rely on mediated “clues” for constructing their perceptions of other individuals. Specifically, we assess whether individuals use the information in email usernames to create basic assumptions about the sender of a message. Ninety‐four male and 206 female participants completed self‐report surveys asking their perceptions of an instructor‐assigned, fictional group member including sex, age, race, and work productivity. A majority of participants assigned biological sex, ethnicity, and age to the fictional member. Participants often identified the creative emails as belonging to Caucasian males, while plain usernames were unknown and perceived as significantly more productive. The majority of participants chose to delete the message, listing lack of recognition as a reason for avoidance. These results suggest that email usernames may shape perceptions when other, nonverbal cues are absent.  相似文献   

9.
Let g be any local property (e.g., gray level or gradient magnitude) defined on a digital picture. Let pg(z) be the relative frequency with which g has value z. At each point (x,y) of the picture we can display pg[g(x,y)], appropriately scaled; the result is called the pg transform of the picture. Alternatively, we can use joint or conditional frequencies of pairs of local properties to define transforms. This note gives examples of such transforms for various gs and discusses their possible uses and limitations.  相似文献   

10.
Problems that are non-quantitative and not bound to a narrow knowledge domain have been served unsatisfactorily by decision support and expert systems. Alternative techniques that address this type of problem are explained here using two key concepts: problem type dependent process support and domain related knowledge. Process support refers to the program steps and the data items useful in finding the solution. Domain related knowledge is knowledge drawn from a specific domain, yet through abstraction applicable to a wider range of problems. Results of preliminary empirical analyses suggest that both concepts are useful.  相似文献   

11.
Automated isolation of total RNA from cultured cells was accomplished by adapting Ambion's solid-phase total RNA isolation kit, RNAqueous-96, for use with the MultiPROBE II liquid handling system from Packard Instruments.Cultured cells (HeLa S3 adherent cells and K562 cells in suspension) were lysed, DNase treated, washed, and then eluted from the 96-well filter plate.Total RNA recovered was analyzed for yield, intactness, purity, and ability to serve as a substrate for real-time RT-PCR.  相似文献   

12.
The main objective of the present article is to improve the bandwidth of a low profile Cylindrical Dielectric Resonator Antenna (CDRA) and operate it for WLAN and “C” band applications. An inverted umbrella shaped CDRA excited by a microstrip feedline with single stub is proposed here. Efficient coupling has been achieved by means of a single stub microstrip feed between DRA and the feed. The new shape of DRA and a single stub microstrip feed improves the bandwidth significantly as high as 28% from 5 to 6.67 GHz which is quite useful for both WLAN and “C” band applications. The proposed antenna is simple in construction, easy to fabricate, low profile and thickness of CDRA is only 5 mm. A parametric study is performed using Ansoft HFSS simulation software to optimize the antenna performance. The proposed CDRA is fabricated and the characteristics of the antenna are measured.  相似文献   

13.
Academic conferences are places of situated learning dedicated to the exchange of knowledge. Knowledge is exchanged between colleagues who are looking to enhance their future research by taking part in several formal and informal settings (lectures, discussions and social events). We studied the processes of knowledge sharing and the influence of the use of IT at the International Conference of Information Systems (ICIS2007) held in Montréal. We describe the categories of knowledge content shared at the conference. Two forms of knowledge sharing were analyzed: formal, guided, planned knowledge sharing in lectures or discussions, and informal knowledge exchange during social events. Data were collected from 274 participants at the conference. The intensity of knowledge sharing in the formal settings was higher compared to the informal settings and was perceived as contributing to future research and to the creation of social relationships. In contrast, informal knowledge sharing contributed mainly to job enhancement and to the initiation of meetings. The discussion centers on planning and evaluating conferences in terms of seeking, creating and sustaining knowledge sharing.  相似文献   

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D. E. Seborg 《Automatica》1971,7(6):761-762
[1] has recently derived a sufficient condition for the global asymptotic stability of a continuous stirred tank reactor. Although the major conclusions of this study appear to be correct, the analysis contains several errors including incorrect stability criteria for the linearized system.  相似文献   

16.
A new LCD referred to as an “Advanced TFT‐LCD” has been developed. It consists of both transmissive and reflective electrodes in every pixel. Its subjective legibility and characteristics, such as contrast ratio, color gamut, and luminance, have been investigated at several ambient illumination intensities. As a result, it was confirmed that Advanced TFT‐LCDs offer better legibility than transmissive LCDs under any ambient illumination intensity.  相似文献   

17.
A piezoelectric transformer (PT) is a device, which can be used for transforming an ac voltage via ultrasonic vibrations. The best characteristics are achieved in the vicinity of mechanical vibration resonance. “Ring-dot” type design of homogeneously poled disk PT was originally proposed by Berlincourt. Only experimental data were published in preceding studies. An analytical continuum model is presented in this work. The effects of dimensions, material properties and electrical load on the voltage gain as well as on the efficiency are calculated. Hard lead zirconate titanate ceramics (PZT, APC841 type) was used for sample fabrication. Studied PTs typically attain transformation ratio equal 20 without load. For load impedance around 5 kΩ, the observed efficiency was above 90%, whereas the transformation ratio dropped down to the values around 2. The model correspondence with experiment is limited by employed approximations. Model limitations are discussed with respect to experimental data.  相似文献   

18.
It is shown that in first-order linear-time temporal logic, validity questions can be translated into validity questions of formulas not containing “next” or “until” operators. The translation can be performed in linear time.  相似文献   

19.
MagneSil™ Paramagnetic Particles are silica-paramagnetic particles with an affinity for nucleic acids under defined conditions. Particle structure and solution composition can be altered to selectively adsorb nucleic acids based upon type and size. These properties have been used to develop purification methods based on a three-step bind, wash, and elute process. The MagneSil™ technology is readily adaptable to robotic platforms, allowing complete automation of the purification process in either 96- or 384- well plate formats. This article introduces the basic physical and performance characteristics of the MagneSil™ Paramagnetic Particles.  相似文献   

20.
Uncivil discourse is a growing concern in American rhetoric, and this trend has expanded beyond traditional media to online sources, such as audience comments. Using an experiment given to a sample representative of the U.S. population, we examine the effects online incivility on perceptions toward a particular issue—namely, an emerging technology, nanotechnology. We found that exposure to uncivil blog comments can polarize risk perceptions of nanotechnology along the lines of religiosity and issue support.  相似文献   

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