用作传感器的小型体波和声表面波石英振荡器

本文叙述了使用音叉体波谐振器或声表面波器件的石英振荡器所构成的传感器.通过在欧洲不同实验室所作的研究说明了温度、压力、气流和力的测量方法.     

含砷难处理金矿石的生物氧化

为了确定加工过程中砷的最终结果，评价生物予处理对金提取的影响，研究了难处理合砷金矿石的生物氧化。试验是在半－间歇搅拌生物反应器、连续流搅拌生物反应器和巨柱式生物浸出系统中，使用铁和硫化物联合氧化细菌进行的。监测了生物氧化过程中硫化物的氧化和砷的溶解作用，并将其结果与随后进行的氰化试验过程中的贵金属的提取联系起来。另外，采用阴离子高效液相色谱／原子吸收光谱技术监测了存在于溶液中的亚砷酸盐［Ａｓ（Ⅲ）］和砷酸盐［Ａｓ（Ｖ）］浓度随时间的变化；还评价了最终尾矿和中和生物氧化溶液所得到的含砷矿泥的稳定性。浸出结果表明，使用生物氧化工艺从这种矿石中可获得９５％以上硫化物氧化率和４７％的砷提取率。在生物予处理后的氰化过程中金的提取率由４９％增加到约８０％。溶液中砷的总浓度高达１７ｇ／Ｌ对细菌数目并无明显的不利影响。在所有情况下，砷最初以Ａｓ（Ⅲ）形式溶解。典型的浸出液里Ａｓ（Ⅲ）的含量是Ａｓ（Ⅴ）的１８倍。由于Ａｓ（Ⅲ）化合物比Ａｓ（Ⅴ）化合物稳定性差且毒性大得多，因此矿泥物料在环境中的长期稳定性是至关重要的。本文将对矿泥毒性浸出过程稳定性试验结果加以论述。     

实时解释提高了勘探／开发决策水平

本文介绍了实时解释的优点及与实时解释相关的技术。文中讨论的技术论题包括：并行处理技术、信息评价技术、三维可视化、综合网络、未来的解释系统。     

高炉炉缸的内部状态

通过使用风口取样器沿高炉半径方向采集炉缸中心试样和利用放射性示踪技术监视铁水和炉渣流动情况的方法，可帮助人们更好地了解炉缸的内部状态。     

Automated zebrafish chorion removal and single embryo placement: optimizing throughput of zebrafish developmental toxicity screens

The potential of the developing zebrafish model for toxicology and drug discovery is limited by inefficient approaches to manipulating and chemically exposing zebrafish embryos-namely, manual placement of embryos into 96- or 384-well plates and exposure of embryos while still in the chorion, a barrier of poorly characterized permeability enclosing the developing embryo. We report the automated dechorionation of 1600 embryos at once at 4 h postfertilization (hpf) and placement of the dechorionated embryos into 96-well plates for exposure by 6 hpf. The process removed ≥95% of the embryos from their chorions with 2% embryo mortality by 24 hpf, and 2% of the embryos malformed at 120 hpf. The robotic embryo placement allocated 6-hpf embryos to 94.7% ± 4.2% of the wells in multiple 96-well trials. The rate of embryo mortality was 2.8% (43 of 1536) from robotic handling, the rate of missed wells was 1.2% (18 of 1536), and the frequency of multipicks was <0.1%. Embryo malformations observed at 24 hpf occurred nearly twice as frequently from robotic handling (16 of 864; 1.9%) as from manual pipetting (9 of 864; 1%). There was no statistical difference between the success of performing the embryo placement robotically or manually.     

An approach to automated detection of tumors in mammograms

An automated system for detecting and classifying particular types of tumors in digitized mammograms is described. The analysis of mammograms is performed in two stages. First, the system identifies pixel groupings that may correspond to tumors. Next, detected pixel groupings are subjected to classification. The essence of the first processing stage is multiresolution image processing based on fuzzy pyramid linking. The second stage uses a classification hierarchy to identify benign and malignant tumors. Each level of the hierarchy uses deterministic or Bayes classifiers and a particular measurement. The measurements pertain to shape and intensity characteristics of particular types of tumors. The classification hierarchy is organized in such a way that the simplest measurements are used at the top, with the system stepping through the hierarchy only when it cannot classify the detected pixel groupings with certainty.     

Model-driven design for the visual analysis of heterogeneous data

As heterogeneous data from different sources are being increasingly linked, it becomes difficult for users to understand how the data are connected, to identify what means are suitable to analyze a given data set, or to find out how to proceed for a given analysis task. We target this challenge with a new model-driven design process that effectively codesigns aspects of data, view, analytics, and tasks. We achieve this by using the workflow of the analysis task as a trajectory through data, interactive views, and analytical processes. The benefits for the analysis session go well beyond the pure selection of appropriate data sets and range from providing orientation or even guidance along a preferred analysis path to a potential overall speedup, allowing data to be fetched ahead of time. We illustrate the design process for a biomedical use case that aims at determining a treatment plan for cancer patients from the visual analysis of a large, heterogeneous clinical data pool. As an example for how to apply the comprehensive design approach, we present Stack'n'flip, a sample implementation which tightly integrates visualizations of the actual data with a map of available data sets, views, and tasks, thus capturing and communicating the analytical workflow through the required data sets.     

Detection of sudden pedestrian crossings for driving assistance systems

In this paper, we study the problem of detecting sudden pedestrian crossings to assist drivers in avoiding accidents. This application has two major requirements: to detect crossing pedestrians as early as possible just as they enter the view of the car-mounted camera and to maintain a false alarm rate as low as possible for practical purposes. Although many current sliding-window-based approaches using various features and classification algorithms have been proposed for image-/video-based pedestrian detection, their performance in terms of accuracy and processing speed falls far short of practical application requirements. To address this problem, we propose a three-level coarse-to-fine video-based framework that detects partially visible pedestrians just as they enter the camera view, with low false alarm rate and high speed. The framework is tested on a new collection of high-resolution videos captured from a moving vehicle and yields a performance better than that of state-of-the-art pedestrian detection while running at a frame rate of 55 fps.     

Co-located collaborative visual analytics around a tabletop display

Co-located collaboration can be extremely valuable during complex visual analytics tasks. We present an exploratory study of a system designed to support collaborative visual analysis tasks on a digital tabletop display. Fifteen participant pairs employed Cambiera, a visual analytics system, to solve a problem involving 240 digital documents. Our analysis, supported by observations, system logs, questionnaires, and interview data, explores how pairs approached the problem around the table. We contribute a unique, rich understanding of how users worked together around the table and identify eight types of collaboration styles that can be used to identify how closely people work together while problem solving. We show how the closeness of teams’ collaboration and communication influenced how they performed on the task overall. We further discuss the role of the tabletop for visual analytics tasks and derive design implications for future co-located collaborative tabletop problem solving systems.     

An algorithm for three-dimensional reconstruction incorporating cross-plane rays

Conventional multislice positron cameras reconstruct a three-dimensional distribution of a positron-emitting radioscope as a set of two-dimensional transverse sections. Consequently, annihilation photons which cross two or more planes are eliminated from the data. Such an approach makes efficient use of the emitted photon flux. A method is proposed which makes more efficient use of the available photons by including both oblique and transverse section in the reconstruction. The implementation of the method consists of centering a scaled convolution filter on each detected coincidence event line and backprojecting the filter values through the three-dimensional reconstruction volume. The final image is normalized to allow for the different number of oblique and transverse sections that contribute to each point in the imaging volume. The method has been evaluated using both simulated data and measured data obtained with a routing area detector positron camera.