Learning with dynamic and static visualizations: Realistic details only benefit learners with high visuospatial abilities

Learning environments can nowadays easily be enriched with different presentation formats of visualizations, because computer graphics technology is constantly and rapidly developing. This study investigates the effectiveness of dynamic compared to static visualizations. Moreover, the influence of realistic details in the visualizations as well as learners’ prerequisites in terms of their visuospatial abilities were addressed. Eighty university students were randomly assigned to four conditions of a two-by-two between subjects design with the two independent variables dynamism and realism. Learning outcomes were measured by means of a verbal factual knowledge test about the terminology and visuospatial details and a pictorial recognition test about the dynamic processes. Data analyses revealed no effects for factual knowledge. With respect to recognition, learners with dynamic visualizations outperformed learners with static visualizations. Furthermore, there was an interaction between learners’ visuospatial abilities and the degree of realism in the visualization: learners with lower visuospatial abilities showed better recognition with schematized visualizations, whereas learners with higher visuospatial abilities showed better recognition with realistic visualizations. The results imply that when designing instructional materials, both the type of knowledge that has to be acquired as well as learners’ prerequisites such as their visuospatial abilities need to be considered.     

2000-2005年广东省食品中食源性致病菌的监测与分析

为了解广东省食品中食源性致病菌的污染状况和污染水平。按国家监测网的工作手册进行了食源性致病菌的检测和菌密度测定,应用RiboPrinterMicrobial Characterization System检测分离菌株的基因指纹图谱,纸片法作药敏试验。在监测的10类2265份食品中,共分离出76株沙门菌、75株单核细胞增生性李斯特菌、161株副溶血性弧菌、2株空肠弯曲菌、2株O157∶H7大肠杆菌。5种食源性致病菌的检出率为13.95%。部分分离的菌株基因指纹图谱分析的结果是:58株沙门菌分属于22个血清型,25株单核细胞增生性李斯特菌分属于11个RP基因型,55株副溶血性弧菌分属于14个RP基因型。药敏试验结果显示,沙门菌、副溶血性弧菌、O157∶H7大肠杆菌均有多重耐药株,单核细胞增生性李斯特菌对抗生素产生耐药性的比例较低。沙门菌、单核细胞增生性李斯特菌和副溶血性弧菌阳性样品中的几何平均菌密度分别为265、96CFU/g和93MPN/100g。5种食源性致病菌对广东省食品的污染普遍存在。肉类食品和水产品的污染尤为严重,政府相关部门应尽快对畜牧养殖业抗生素的使用进行科学指导,并制定相关的法规进行监督和约束。     

Image analysis: Problems,progress and prospects

Over the past 25 years, many ad hoc techniques for analyzing images have been developed and the subject has gradually begun to develop a scientific basis. This paper outlines the basic steps in a general image analysis process. It summarizes the state of the art with respect to each step, points out limitations of present methods and indicates potential directions for future work.     

A region-based formalism for picture processing

A set of structures and operations is proposed in terms of which picture processing algorithms can be expressed. The rectangular array model which has traditionally been used for this purpose is discussed and certain weaknesses in it are revealed. The structures and operations which comprise the formalism are described. They are based on the concept of a region. As an example an algorithm has been taken from the literature and is described using the formalism.     

A feasible computer system for grey-level,pictorial pattern recognition

A general-purpose interactive hardware-software system is described which allows the analysis, representation and enhancement of poor quality, multiple-frame, grey-level pictures. A precise, computer-controlled, high-speed, random-access flying-spot scanner is used. Contour-finding, piece-wise linear fitting and global region-extraction algorithms with an interactive executive program are described. The results obtained when the system was applied to straight line drawings and cine-angiograms are given.     

Generating an image that affords slant perception from stereo,without pictorial cues

This paper describes an algorithm for generating a planar image that when tilted provides stereo cues to slant, without contamination from pictorial gradients. As the stimuli derived from this image are ultimately intended for use in studies of slant perception under magnification, a further requirement is that the generated image be suitable for high-definition printing or display on a monitor. A first stage generates an image consisting of overlapping edges with sufficient density that when zoomed, edges that nearly span the original scale are replaced with newly emergent content that leaves the visible edge statistics unchanged. A second stage reduces intensity clumping while preserving edges by enforcing a broad dynamic range across the image. Spectral analyses demonstrate that the low-frequency content of the resulting image, which would correspond to the pictorial cue of texture gradient changes under slant, (a) has a power fall-off deviating from 1/f noise (to which the visual system is particularly sensitive), and (b) does not offer systematic cues under changes in scale or slant. Two behavioral experiments tested whether the algorithm generates stimuli that offer cues to slant under stereo viewing only, and not when disparities are eliminated. With a particular adjustment of dynamic range (and nearly so with the other version that was tested), participants viewing without stereo cues were essentially unable to discriminate slanted from flat (frontal) stimuli, and when slant was reported, they failed to discriminate its direction. In contrast, non-stereo viewing of a control stimulus with pictorial cues, as well as stereoscopic observation, consistently allowed participants to perceive slant correctly. Experiment 2 further showed that these results generalized across a population of different stimuli from the same generation process and demonstrated that the process did not substitute biased slant cues.     

虚拟测试系统G语言编程的设计与实现

介绍了LabVIEW环境下的编程特点及调试方式,基于LabVIEW环境应用G语言,在模块化编程条件下方快捷地组建虚拟测试系统,经实际应用明,G语言是一种快速高效的开发环境,可以在短时间内开发出高效、高性能的智能仪器。     

寓画于园，以画探园：《红楼梦》大观园园林空间的画意营造 #

曹雪芹对大观园的空间营造与当时寓画于园的宗旨息息相关,以山水画的空间法则解析大观园园林空间营造意匠,可以拓宽中国传统园林空间的画意内涵。大观园园林空间在动态游观法则下,从整体与局部、空间序列、景观集群三个方面推进了园林空间形态的完善;在气韵生动法则下,从风声、水声、动物声三种声景营造加强了园林空间结构的音韵流通;在象征隐喻法则下,从植物象征与文学象征引发了园林空间氛围的意境呈现。大观园园林空间的画意营造,既继承了传统文化的经典内核,又有园林空间形态、结构与氛围方面的创新和拓展,体现了诗意栖居的和谐境界。     

PDB: A pictorial database oriented to data analysis

The paper describes a new pictorial database oriented to image analysis, implemented inside the MIDAS data analysis system. Pictorial databases need expressive data structures in order to represent a wide class of information from the numerical to the visual. The model of the database is relational; however, a full normalization is not achievable, owing to the complexity of the visual information. The paper reports the general design and notes on the software implementation. Preliminary experiments show the performance of the pictorial database.