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1.
We investigate formal power series on pictures. These are functions that map pictures to elements of a semiring and provide an extension of two-dimensional languages to a quantitative setting. We establish a notion of a weighted MSO logics over pictures. The semantics of a weighted formula will be a picture series. We introduce weighted 2-dimensional on-line tessellation automata (W2OTA) and prove that for commutative semirings, the class of picture series defined by sentences of the weighted logics coincides with the family of picture series that are computable by W2OTA. Moreover, we show that the family of behaviors of W2OTA coincide precisely with the class of picture series characterized by weighted (quadrapolic) picture automata and consequently, the notion of weighted recognizability presented here is robust. However, the weighted structures can not be used to get better decidability properties than in the language case. For every commutative semiring, it is undecidable whether a given MSO formula has restricted structure or whether the semantics of a formula has empty support.  相似文献   

2.
In this paper, we propose an album-oriented face-recognition model that exploits the album structure for face recognition in online social networks. Albums, usually associated with pictures of a small group of people at a certain event or occasion, provide vital information that can be used to effectively reduce the possible list of candidate labels. We show how this intuition can be formalized into a model that expresses a prior on how albums tend to have many pictures of a small number of people. We also show how it can be extended to include other information available in a social network. Using two real-world datasets independently drawn from Facebook, we show that this model is broadly applicable and can significantly improve recognition rates.  相似文献   

3.
针对基于图像和视频的动作识别系统具有特征采集设备复杂、视角固定和需要采集多视角图像等缺点,提出基于加速度特征的可拓动作识别方法。该方法利用物体向不同方向运动时,其关键部位点的三轴加速度具有一定区分度的特点,结合可拓识别方法,实现动作识别。在构建的手臂动作识别系统中,测得动作识别率可达94.4%。该方法可应用于智能监控、医疗电子等领域。  相似文献   

4.
计算机三维动画是计算机技术不断发展的产物,它以无可比拟的感官感受和巨大的功能给影视行业、动画产业以及电子游戏行业带来了巨大的突破,给人们呈现了无与伦比的完美画面,是当今影视及游戏行业无可取代的重要技术,并在人们的生活领域不断延伸渗透,因此受到业内人士的高度重视。新行业的发展不可避免的会出现各种各样的难题,该文将围绕国内计算机三维动画产业的发展问题进行探讨。  相似文献   

5.
In this paper we describe a computational architecture for applications that support heterogeneous reasoning. Heterogeneous reasoning is, in its most general form, reasoning that employs representations drawn from multiple representational forms. Of particular importance, and the principal focus of the architecture, is heterogeneous reasoning which employs one or more forms of graphical representation, perhaps in combination with sentences (of English or another language, whether natural or scientific). Graphical representations include diagrams, pictures, layouts, blueprints, flowcharts, graphs, maps, tables, spreadsheets, animations, video, and 3D models. By ‘an application that supports heterogeneous reasoning’ we mean an application that allows users to construct, record, edit, and replay a process of reasoning using multiple representations so that the structure of the reasoning is maintained and the informational dependencies and justifications of the individual steps of the reasoning can be recorded.  相似文献   

6.
We introduce the generalized nonogram, an extension of the well‐known nonogram or Japanese picture puzzle. It is not based on a regular square grid but on a subdivision (arrangement) with differently shaped cells, bounded by straight lines or curves. To generate a good, clear puzzle from a filled line drawing, the arrangement that is formed for the puzzle must meet a number of criteria. Some of these relate to the puzzle and some to the geometry. We give an overview of these criteria and show that a puzzle can be generated by an optimization method like simulated annealing. Experimentally, we analyze the convergence of the method and the remaining penalty score on several input pictures along with various other design options.  相似文献   

7.
H.264/AVC scalable video coding (H.264/AVC SVC), as the scalable extension of H.264/AVC, offers the flexible adaptivity in terms of spatial, temporal and SNR scalabilities for the generated bitstream. However, such compressed video still suffers from the bad playback quality when packet loss occurs over unreliable networks. In this paper, we present an error concealment algorithm to tackle the whole-picture loss problem in H.264/AVC SVC when hierarchical B-picture coding is used to support temporal scalability. In the proposed algorithm, by taking advantage of the temporal relationship among the adjacent video pictures, the motion information of the lost picture is derived simply and efficiently based on the principle of temporal direct mode. Utilizing the derived motion information, the lost picture is concealed by performing motion compensation on the correctly received temporally previous and future video pictures. The experimental results demonstrate that as a post-processing tool, the proposed error concealment algorithm is able to significantly improve both the objective and subjective qualities of the decoded video pictures in the presence of packet losses when compared to the error concealment algorithm used in H.264/AVC SVC reference software. The proposed method can also be applied to H.264/AVC with hierarchical B-picture coding for error concealment.  相似文献   

8.
为直观地分析左心室在心脏收缩期的形变情况,提出一种左心事力学形态分析方法.首先利用带标记线的心脏核磁共振图像数据针对左心室建立系数可变的物理可形变模型,并在所建模型的基础上,利用心脏收缩期各个时刻的左心室轮廓点数据恢复三维外形;然后利用心脏收缩期各相邻时刻的标记点数据计算左心室模型外力;最后将模型外力转换为收缩应力分量、切向应力分量和拉伸应力分量,并将各个应力分量用彩色云图显示.实验结果表明,文中方法能直观、有效地反映左心室内外表面在整个心脏收缩期的应力分布及形变趋势,获取的力学形态变化云图将成为重要的医学诊断依据.  相似文献   

9.
“ART PROCESSOR” is a compact image processing system using a microprocessor. It can produce artistic pictures like oil painting from realistic pictures like photographs. We will present the image processing system and the algorithm to create artistic pictures in this paper.  相似文献   

10.
An algebraic system for binary digital pictures has already been described, along with the definition of the four arithmetic rules. In this paper, an extension of the binary algebraic system to a 2n-valued one is first proposed. It then becomes evident that this extended algebraic system satisfies several properties including those of a ring. An example of a 2n-valued model, an eight-valued algebraic system, is introduced and applied to painted digital pictures. Pictorial operations such as multiple arrangement, enlargement, differentiation, integration, and color changes are then dealt with by the combinations of the four arithmetic rules.  相似文献   

11.
This study explores whether people orient to and encode pictures differently depending on whether the pictures were chosen from a limited or an extensive array of options. Participants viewed pictures on a computer as part of a within-subjects experiment (N = 43). In one condition, participants viewed pictures that they had chosen from a limited array of 6 options. In the other condition, participants viewed pictures chosen from an extensive array of 24 options. Heart rate and recognition served as indicators of orienting and encoding. Results showed that pictures chosen from limited options elicited orienting responses. Pictures chosen from extensive options, on the other hand, did not elicit orienting responses. Recognition was fastest and most accurate for pictures selected from limited options, suggesting that participants encoded them better. Based on these results, we suggest ways of conceptualizing the attributes of computer media that uniquely affect cognitive processing.  相似文献   

12.
An Interactive Computer Graphics Parking (ICG-PARK) Program which provides an efficient way to design parking lots is described. Using ICG-PARK program, composite pictures of the system can be generated by computer graphics quickly and accurately. The modification or redesign of such pictures can be done easily through interactive display systems.

The area under study is initially drawn with fixed objects. The user can then proceed to any desired subroutine by using the interactive capabilities of the system. The length, direction of row(s) of parking spaces and the dimension of the parking stalls are given by the user each time through the interactive device when a parking stall drawing subroutine is called. Row(s) of parking stalls are drawn on a subpicture. When attached to the cross cursor, it can be moved to the desired location. The approximation of a curve can be drawn by calling the curve drawing subroutine recurrently. The design vehicle minimum turning path curve is provided, and can be used to check the adequacy of the aisle, entrance, and exit layout. The CRT screen can be erased either entirely or partially and redrawn at any time. Finally, a hardcopy of a satisfactory parking lot layout plan can be obtained through the plotter.  相似文献   


13.
刘涛  王淑灵  詹乃军 《软件学报》2017,28(5):1118-1127
近些年来,伴随着人工智能领域的浪潮,机器人越来越多的出现在我们的日常生活中,例如足球机器人、无人机、无人车等.如何保证这些自治机器人尤其是多个机器人在移动过程中的安全成了人们一直很关心的问题.混成通信顺序进程(Hybrid Communicating Sequential Process,HCSP)是一个针对混成系统的形式化建模语言,在通信顺序进程(Communicating Sequential Process,CSP)的基础上引入了微分方程以描述混成系统中的连续行为和控制逻辑,可以方便高效地对大型控制系统尤其是在有通信事件发生时的情形进行形式化建模.本文就是用HCSP建模多机器人的路径控制算法,并用定理证明工具HProver进行形式化验证.结果证明了在满足一定初始条件下,机器人团队在整个运行途中不会发生碰撞.  相似文献   

14.
Estimating the support of a high-dimensional distribution.   总被引:80,自引:0,他引:80  
Suppose you are given some data set drawn from an underlying probability distribution P and you want to estimate a "simple" subset S of input space such that the probability that a test point drawn from P lies outside of S equals some a priori specified value between 0 and 1. We propose a method to approach this problem by trying to estimate a function f that is positive on S and negative on the complement. The functional form of f is given by a kernel expansion in terms of a potentially small subset of the training data; it is regularized by controlling the length of the weight vector in an associated feature space. The expansion coefficients are found by solving a quadratic programming problem, which we do by carrying out sequential optimization over pairs of input patterns. We also provide a theoretical analysis of the statistical performance of our algorithm. The algorithm is a natural extension of the support vector algorithm to the case of unlabeled data.  相似文献   

15.
In his new book, Free Culture (Penguin Press, 2004), Larry Lessig of Stanford Law School presents an excellent explanation of copyright law's effect on creativity - and of large corporations' effect on copyright law. Free Culture covers the history of copyright and its expansion from books to music, pictures, and videos, as well as its extension from 28 to 95 years. The book is remarkable because, unlike the vast majority of flaming on both sides of the downloading controversy, it presents both a factual argument and proposed solutions.  相似文献   

16.
张聪  张慧 《微计算机信息》2007,23(30):302-303,130
本文针对复杂背景下的PDF417条码,提出了一种合理的分割算法。首先使用彩色过滤算法对背景进行过滤,然后利用二次梯度算法提取图像中的正、负峰值,获取图像的分割阈值,使用这种方法后,可在最大程度上减少外界干扰。对于条码的倾斜,使用Hough变换得到图像倾角,再利用二维旋转矩阵旋转图像。为了减少目标区域的毛刺以及空白点,提出了一种良好的插值方法。确保旋转变换后的图像不失真。  相似文献   

17.
Guercin F 《Ergonomics》2007,50(10):1702-1712
The current study examined children's ability to analyse pictures of a risky situation, both in relation to the characteristics of the pictures and in relation to the centering/decentering process of cognitive development. Sixty children aged 6, 9 or 11 years were given an objective or subjective version of a story about a risky situation involving road crossing and were asked to reconstruct it by putting six pictures in chronological order. The type of picture series, objective or subjective, had a different effect on the children's understanding and performance, according to the age. The older children were better at ordering the pictures, but on the subjective version only. The picture-version effect on planning time decreased with age; only the younger children took more time to start touching the pictures. On one hand, it is concluded that for the youngest children, objective representations are essential to analysing pictures showing a risk, whereas the oldest children will profit more from a subjective view. On the other hand, subjective representations, which give a more realistic view, provide an excellent tool for testing children's abilities. Subjective representations can be used to detect potentially risky behaviour in virtual situations (static pictures, or multimedia tools), since it permits one to predict at-risk behaviour in the street and to assess the effectiveness of remedial measures.  相似文献   

18.
Most visual diagramming tools provide point‐and‐click construction of computer‐drawn diagram elements using a conventional desktop computer and mouse. SUMLOW is a unified modelling language (UML) diagramming tool that uses an electronic whiteboard (E‐whiteboard) and sketching‐based user interface to support collaborative software design. SUMLOW allows designers to sketch UML constructs, mixing different UML diagram elements, diagram annotations, and hand‐drawn text. A key novelty of the tool is the preservation of hand‐drawn diagrams and support for manipulation of these sketches using pen‐based actions. Sketched diagrams can be automatically ‘formalized’ into computer‐recognized and ‐drawn UML diagrams and then exported to a third party CASE tool for further extension and use. We describe the motivation for SUMLOW, illustrate the use of the tool to sketch various UML diagram types, describe its key architecture abstractions and implementation approaches, and report on two evaluations of the toolset. We hope that our experiences will be useful for others developing sketching‐based design tools or those looking to leverage pen‐based interfaces in software applications. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

19.
We have previously reported an algorithm (Yamamoto and Yoshikura, 1985) for the prediction of optimum and suboptimum RNA folding structures. The calculation data was presented as an 'information map'. However, the result was affected by the starting point of calculation. In this paper, we have improved the method so that the result will not be affected by the starting point. In addition, we present a method of converting the information map into a set of pictures of optimal and suboptimal molecular structures.  相似文献   

20.
Animations and videos are often designed to present information that involves change over time, in such a way as to aid understanding and facilitate learning. However, in many studies, static displays have been found to be just as beneficial and sometimes better. In this study, we investigated the impact of presenting together both a video recording and a series of static pictures. In experiment 1, we compared 3 conditions (1) video shown alone, (2) static pictures displayed alone, and (3) video plus static pictures. On average the best learning scores were found for the 3rd condition. In experiment 2 we investigated how best to present the static pictures, by examining the number of pictures required (low vs. high frequency) and their appearance type (static vs. dynamic). We found that the dynamic presentation of pictures was superior to the static pictures mode; and showing fewer pictures (low frequency) was more beneficial. Overall the findings support the effectiveness of a combination of instructional animation with static pictures. However, the number of static pictures, which are used, is an important moderating factor.  相似文献   

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