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41.
ATOM 1.0:基于GPU的电子断层重构软件   总被引:1,自引:0,他引:1  
电子断层成像技术能够在纳米尺度下重构出不具有全同性的细胞或大分子的三维结构,正受到越来越广泛的重视。针对现有电子断层成像技术中重构软件的不足,特别是迭代重构算法速度慢的缺点,我们开发了一款基于Graphic Processor Unit(GPU)平台的电子断层重构软件——ATOM,实现了图像对位、重构参数计算、三维重构及数据可视化等电子断层重构的基本功能。其中,在二维对位方面,ATOM实现了迭代的无标记平移和旋转对位;在三维重构方面,实现了背投影和多种迭代重构算法,并实现了迭代重构在GPU平台上的并行加速,获得了良好的加速比,如SIRT算法得到了47倍加速比。ATOM是绿色开源软件,可以运行在支持Qt和CUDA的所有操作系统上。ATOM为图形界面软件,结合详尽的安装及使用文档,便于用户使用。  相似文献   
42.
It is a practical necessity for non-professional users to interpret biologically derived Raman spectral information for obtaining accurate and reliable analytical results. An integrated Raman spectral analysis software (NWUSA) was developed for spectral processing, analysis, and feature recognition. It provides a user-friendly graphical interface to perform the following preprocessing tasks: spectral range selection, cosmic ray removal, polynomial fitting based background subtraction, Savitzky–Golay smoothing, area-under-curve normalization, mean-centered procedure, as well as multivariate analysis algorithms including principal component analysis (PCA), linear discriminant analysis, partial least squares-discriminant analysis, support vector machine (SVM), and PCA-SVM. A spectral dataset obtained from two different samples was utilized to evaluate the performance of the developed software, which demonstrated that the analysis software can quickly and accurately achieve functional requirements in spectral data processing and feature recognition. Besides, the open-source software can not only be customized with more novel functional modules to suit the specific needs, but also benefit many Raman based investigations, especially for clinical usages.  相似文献   
43.
Life cycle assessments of circular economy measures (CE LCA) of consumer products have been criticized for oversimplifying important aspects of the use phase such as user behavior and rebound effects, limiting our understanding of the environmental performance of circular economy measures. This study tests the usefulness of a framework designed to facilitate accounting for such aspects, by applying the framework to a case study of reuse of shell jackets enabled by “premium secondhand” outdoor stores. Methods for collecting use phase data were user surveys and interviews with store managers. Using the framework on this case study generated several novel insights which are interesting in themselves and as inputs to CE LCA. For instance, secondhand shell jackets have a significantly lower frequency of use during their first use span compared to the second and to shell jackets in the linear reference scenario. This implies that reuse in this case does not function as a mere use extension of otherwise similar use phases as is commonly assumed. The generation of such insights, which hitherto have been lacking in CE LCAs, points to the usefulness of the framework as a tool for opening the “black box” of the use phase in CE LCAs to improve understanding of the environmental performance of circular economy measures.  相似文献   
44.
Consumer retrieval of health information through the internet has become prevalent. In the past, physicians provided filtered health information to the consumer. However, the availability of health related information including disease specific research trends over the World Wide Web is useful for clinicians and consumers. The use of internet based health care information by clinicians and consumers have increased in recent years. Nonetheless, consumers often have difficulties in evaluating such data in a comprehensive manner. Here, we describe the current status of health care related data over the World Wide Web.  相似文献   
45.
In the urban forest of Stuttgart the forest roads are used by a growing number of people for recreational and leisure activities. To manage and channel the different user groups within an optimised forest road network needs a lot of information: Number and composition of visitors, demands of different user groups concerning standard of roads and trails they use for their activities, conflicts that may rise between different users using the same road at the same time, dedication of roads to special activities (e.g. fitness trail, hiking trail).

A relatively new method of video monitoring was used to collect long-term information about number and composition of visitors, personal interviews with “experts” were made to obtain information about the specific demands of the different user groups, and analysis of road network was done with the help of GIS. The results show that these tools complement one another quite well and the combination of obtained data may help to channel visitor flows and to minimise conflicts between different user groups.  相似文献   

46.
The stocking of trout in wilderness lakes of the western United States began in the 1800s. This practice was followed for nearly a century with the singular goal of creating and enhancing sport fishing and without any consideration of its ecological ramifications. Following the advent of a new environmental awareness in the 1960s, and thanks to new research that revealed negative impacts on the biota attributable to introduced fishes, traditional fish-stocking practices came under question first at federal land management agencies and later at their counterparts within the states. The highly utilitarian ethic that drove resource management until well into the 1960s was gradually replaced by one that acknowledges the value of all life forms and their ecological complexity, a view currently supported even by many anglers. The necessity for wilderness fish stocking is now the subject of widespread debate, especially in view of changing social values and priorities. Options for future generations cannot be preserved if introductions continue to erode the biodiversity of mountain lake ecosystems. Received 28 March 2000; accepted 30 May 2000.  相似文献   
47.
《IRBM》2023,44(3):100746
Objectivethis paper presents an innovative graphical user interface to visualize the attitude of a sensing device in a three-dimensional space, serving a wide-range of medical applications.Material and methodsbased on inertial measurement units (IMU) or on magnetic, angular rate and gravity (MARG) sensors, a processing unit provides Euler angles using a sensor fusion technique to display the orientation of the device relative to the Earth frame in real-time. The device is schematized by linking six polygonal regions, and is subject to sequential rotations by updating the graph each 350 ms. We conduct comparative studies between the two sensing devices, i.e. IMUs and MARGs, as well as two orientation filters, namely Madgwick's algorithm and Mahony's algorithm.Resultsthe accuracy of the system is reported as a function of (i) the sampling frequency, (ii) the sensing unit, and (iii) the orientation filter, following two elderly care applications, namely fall risk assessment and body posture monitoring. The experiments are conducted using public datasets. The corresponding results show that Madgwick's algorithm is best suited for low sampling rates, whereas MARG sensors are best suited for the detection of postural transitions.Conclusionthis paper addresses the different aspects and discusses the limitations of attitude estimation systems, which are important tools to help clinicians in their diagnosis.  相似文献   
48.
Accurate measurements of ring-width series are essential for dendrochronological analyses. We present an R package MtreeRing for ring-width measurements on scanned digital images. A morphological alternate sequential filter is used for noise reduction in the original image. Ring boundaries are determined by the steepest negative slopes in the light reflectance of latewood-earlywood transitions. To automatically identify tree rings, the package provides three alternative methods (watershed-based segmentation, Canny edge detector, and a linear detection algorithm), each with advantages and disadvantages and suited to different wood anatomical features. The user can also manually mark tree rings on species with complex anatomical structures. The arcs of inner-rings and angles of successive inclined ring boundaries are used to correct ring-width series. Differences in ring-width measurements between MtreeRing and WinDENDRO in a given coniferous species (Larix gmelinii) were assessed, and no significant difference between programs was found. Furthermore, the package provides an R-based web application which was developed using the Shiny framework. This beginner-friendly application allows viewing and interacting with tree ring images. It requires no programming experience and can run on either a local computer or a remote server.  相似文献   
49.
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