3维建模中视频图像与磁跟踪器的多模态标定在微创手术中的应用

提出了一种全自动、多模态的信息融合解决方案用于配准视频图像和磁跟踪数据。该配准方案将用于内窥镜图像的三维数字成像系统以对人体的三维解剖结构的外观和尺度进行重建,特别是用于微创手术。多模态标定方法如下：首先医生将磁跟踪器插入并固定于内窥镜的工作通道;然后利用该器械组对一个棋盘格模板的各个视角进行若干秒的采集;内窥镜坐标和磁跟踪器坐标的相对关系（平移和旋转）就可以立刻得到。在手术过程中,磁跟踪器显示的读数将可以自动用来推算出内窥镜的坐标（位置和朝向）,并有利于重建器官的三维结构。虽然目前已有一些深入研究的算法用于从图像中推算相机的运动,他们通常非常容易受到图像分析、误差积累、结构形变等的影响。从实验结果分析可知,该方案提出使用磁跟踪器推算相机运动参数的方法可行且提高了精度。此外,该方法不需要特殊的训练或者昂贵的设备。     

基于灭点理论和平面控制场的相机标定方法研究

给出了一种基于灭点理论和平面控制场的相机解析自标定方法。在系统分析平面场景灭点几何的基础上,依据灭点理论并结合2维场景的共线方程严密论证和推导了平面控制场中相机外方位元素初值的实用算法。给出了一种圆形标志点的快速检测及定位方法,提出了一种基于计算可靠性矩阵QVVP的自检校光束法平差中各类观测值权值的确定方法。实验证明了该相机标定方法的正确性和有效性,为相机标定探索了一种可行的方法。     

浅析商品包装设计中的“德”与“信”

为了在激烈的竞争中获取利润,一些商业欺诈现象泛滥成灾,不但未能受到遏制反而因技术的现代化而愈趋隐蔽。以低质低价的产品混充优质产品在一些业主看来似乎永远是一条致富的捷径。如果说设计艺术不单纯是为了美化我们的生活,更重要的是要提高我们日常生活的质量的话,那么,设计师就有义务推动和促进公平交易的实现。     

基于“互联网+”和“大数据”的输电交互式巡检安全质量管控体系的探索和实践

跟随我国电力体制的深入改革,输电线路的构建规模持续扩大,经济的高速发展、社会的不断进步和人民生活水平的逐步提高都对电力系统运行的安全性提出了更高要求,为了跟上当前这种形式,满足全社会不断提高的用电需求,供电企业必须增强对输电线路安全质量的管控。国网龙岩供电公司以“一六八”新时代发展战略体系为核心,基于“互联网+”和“大数据”技术的发展,以完善传统巡检模式的不足为导向,以推动输电交互式巡检安全质量管控为引领,构建以“过程管控”为目的的输电交互巡检管控模式,搭建“工学一体”的信息交流平台,形成“全程记录”巡检数据库体系,全方位提升巡检工作安全质量及效率。该管控体系应用后,确实能确保巡检数据完整性,减少缺陷隐患漏报率,缩短现场紧急事件响应时间、新人培训上岗时间、常用报表统计时间等,能全面提升巡检安全质量。     

On the “dimensionality curse” and the“self-similarity blessing”

Spatial queries in high-dimensional spaces have been studied extensively. Among them, nearest neighbor queries are important in many settings, including spatial databases (Find the k closest cities) and multimedia databases (Find the k most similar images). Previous analyses have concluded that nearest-neighbor search is hopeless in high dimensions due to the notorious “curse of dimensionality”. We show that this may be overpessimistic. We show that what determines the search performance (at least for R-tree-like structures) is the intrinsic dimensionality of the data set and not the dimensionality of the address space (referred to as the embedding dimensionality). The typical (and often implicit) assumption in many previous studies is that the data is uniformly distributed, with independence between attributes. However, real data sets overwhelmingly disobey these assumptions; rather, they typically are skewed and exhibit intrinsic (“fractal”) dimensionalities that are much lower than their embedding dimension, e.g. due to subtle dependencies between attributes. We show how the Hausdorff and Correlation fractal dimensions of a data set can yield extremely accurate formulas that can predict the I/O performance to within one standard deviation on multiple real and synthetic data sets     

双闭式同机架启闭机在武定门闸加固中的设计和应用

武定门节制闸工程启闭机原为2×100kN上、下扉联动卷扬式启闭机,已运行近50年,但联动运行方式布置复杂,安全性差,启闭速度慢,启闭设备布置分散、零乱,不利于管理,设备运行维护困难,存在严重的安全隐患。根据相关标准、规范及批复,武定门节制闸启闭机必须报废更新。本文针对该启闭机启闭联动机构复杂、启闭速度慢、钢丝绳寿命短等特点,对该工程启闭机传动机构和布置形式进行了重新设计。     

Applying relation algebra and R<Emphasis Type="SmallCaps">el</Emphasis>V<Emphasis Type="SmallCaps">iew</Emphasis> to solve problems on orders and lattices

Relation algebra is well suited for dealing with many problems on ordered sets. Introducing lattices via order relations, this suggests to apply it and tools for its mechanization for lattice-theoretical problems, too. We combine relation algebra and the BDD-based specific purpose Computer Algebra system RelView to solve some algorithmic problems on orders and lattices and to visualize their solutions.     

Embedding OWA under preference ranking for DEA cross-efficiency aggregation: Issues and procedures

Cross-efficiency (CE) evaluation is an extension of data envelopment analysis (DEA) used for fully ranking decision-making units (DMUs). The ranking process is normally performed on the matrix of CE scores. An ultimate efficiency score is computed for each DMU through an adequate amalgamation process. The preference ranking approach can be seen as an amalgamation technique based on the rank orders of the CE scores. In this paper, we review this approach by putting more emphasis on the aggregation aspect. We highlight the zero vote issue and we show that the latter has been neglected in the extant aggregation procedures. Consequently, we develop two ordered weighted averaging (OWA)-based procedures that attempt to meet effectively the requirements of an aggregation mechanism while exploiting the positive properties of the preference-ranking approach. The merits of the proposed procedures are evaluated on a sample of manufacturing systems by considering, for OWA weights generation, different OWA models with different orness degrees.     

The Carathéodory–Fejér–Pisarenko Decomposition and Its Multivariable Counterpart

When a covariance matrix with a Toeplitz structure is written as the sum of a singular one and a positive scalar multiple of the identity, the singular summand corresponds to the covariance of a purely deterministic component of a time-series whereas the identity corresponds to white noise-this is the Caratheacuteodory-Fejeacuter-Pisarenko (CFP) decomposition. In the present paper we study multivariable analogs for block-Toeplitz matrices as well as for matrices with the structure of state-covariances of finite-dimensional linear systems (which include block-Toeplitz ones). To this end, we develop theory which addresses questions of existence, uniqueness and realization of multivariable power spectra, possibly having deterministic components. We characterize state-covariances which admit only a deterministic input power spectrum, and we explain how to realize multivariable power spectra which are consistent with singular state covariances via decomposing the contribution of the singular part. We then show that multivariable decomposition of a state-covariance in accordance with a "deterministic component + white noise" hypothesis for the input does not exist in general. We finally reinterpret the CFP-dictum and consider replacing the "scalar multiple of the identity" by a covariance of maximal trace which is admissible as a summand. The summand can be either (block-)diagonal corresponding to white noise or have a "short-range correlation structure" corresponding to a moving average component. The trace represents the maximal variance/energy that can be accounted for by a process at the input (e.g., noise) with the aforementioned structure, and this maximal solution can be computed via convex optimization. The decomposition of covariances and spectra according to the range of their time-domain correlations is an alternative to the CFP-dictum with potentially great practical significance     

Contending with Terms: “Multimodal” and “Multimedia” in the Academic and Public Spheres

Scholars have begun naming and defining terms that describe the multifaceted kinds of composing practices occurring in their classrooms and scholarship. This paper analyzes the terms “multimedia” and “multimodal,” examining how each term has been defined and presenting examples of documents, surveys, web sites and others to show when and how each term is used in both academic and non-academic/industry contexts. This paper shows that rather than the use of these terms being driven by any difference in their definitions, their use is more contingent upon the context and the audience to whom a particular discussion is being directed. While “multimedia” is used more frequently in public/industry contexts, “multimodal” is preferred in the field of composition and rhetoric. This preference for terms can be best explained by understanding the differences in how texts are valued and evaluated in these contexts. “Multimodal” is a term valued by instructors because of its emphasis on design and process, whereas “multimedia” is valued in the public sphere because of its emphasis on the production of a deliverable text. Ultimately, instructors need to continue using both terms in their teaching and scholarship because although “multimodal” is a term that is more theoretically accurate to describe the cognitive and socially situated choices students are making in their compositions, “multimedia” works as a gateway term for instructors and scholars to interface with those outside of academia in familiar and important ways.     

Constructing essentialism: Computers and Composition and the “‘risk’ of essence”

Feminist authors in Computers and Composition have generally favored social constructionist approaches to identity, yet a subtle reliance on essentialist assumptions about women (sometimes tied directly to the body) still exists. In order to explore this phenomenon, I rely on the theories of Diana Fuss and Elizabeth Grosz to unpack the essentialist/constructionist binary. Then, relying on Laura Brady's explication of “strategic” and “tactical” deployments of essentialism in composition studies, I discuss two previous articles in Computers and Composition that successfully negotiated issues of women's identity partly through essentialist assumptions. The ways in which the articles under discussion here essentialized teenage girls become stepping stones toward a reconstruction of girls’ identities. Thus, although essentialism can be problematic, feminists interested in writing and technology can still take what Diana Fuss calls a “‘risk’ of essence” to further feminist goals.     

Combinations of <Emphasis Type="Italic">Stit</Emphasis> and Actions

We present a simple theory of actions against the background of branching time, based on which we propose two versions of an extended stit theory, one equipped with particular actions and the other with sets of such actions. After reporting some basic results of a formal development of such a theory, we briefly explore its connection to a version of branching ETL.     

“Sexting” and adult romantic attachment

“Sexting” refers to sending and receiving sexually suggestive images, videos, or texts on cell phones. As a means for maintaining or initiating a relationship, sexting behavior and attitudes may be understood through adult attachment theory. One hundred and twenty-eight participants (M = 22 and F = 106), aged 18-30 years, completed an online questionnaire about their adult attachment styles and sexting behavior and attitudes. Attachment anxiety predicted sending texts that solicit sexual activity for those individuals in relationships. Attachment anxiety also predicted positive attitudes towards sexting such as accepting it as normal, that it will enhance the relationship, and that partners will expect sexting. Sexting may be a novel form for expressing attachment anxiety.     

<Emphasis Type="Italic">k</Emphasis>-Nearest-Neighbor Clustering and Percolation Theory

Let P be a realization of a homogeneous Poisson point process in ℝ ^d with density 1. We prove that there exists a constant k _d , 1<k _d <∞, such that the k-nearest neighborhood graph of P has an infinite connected component with probability 1 when k≥k _d . In particular, we prove that k ₂≤213. Our analysis establishes and exploits a close connection between the k-nearest neighborhood graphs of a Poisson point set and classical percolation theory. We give simulation results which suggest k ₂=3. We also obtain similar results for finite random point sets. Part of the work was done while S.-H. Teng was at Xerox Palo Alto Research Center and MIT. The work of F.F. Yao was supported in part by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China [Project No. CityU 1165/04E].     

Students’ and teachers’ use of Facebook

The purpose of this article is to review current published research studies focusing on the use of Facebook by students and teachers. The aim of the review is not to solely discuss Facebook in relation to teaching or learning purposes, or about its educational value per se, but also to present a detailed account of the participants’ Facebook usage profile or the extent to which users are engaged in Facebook activities. The emphasis of this review will be upon empirical findings rather than opinion- or theoretical explanations. Following the review guidelines set by Creswell (Research Design Qualitative and Quantitative Approaches, 1994), I summarize the hitherto accumulated state of knowledge concerning Facebook and highlight questions or issues that research has left unresolved. This review is organized into three sections that cover the major topics of current research: (a) students’ Facebook usage profile or extent of Facebook use (e.g., time students spend on Facebook each day, students’ motives for using Facebook, as well as various factors that may affect these usage profiles), (b) the effects of Facebook use (e.g., effects of Facebook self-disclosure on teacher credibility, effects of Facebook use on student social presence and discussion, and effects of Facebook on students’ academic performance), and (c) students’ attitudes toward Facebook. The conclusions overall suggest that Facebook thus far has very little educational use, that students use Facebook mainly to keep in touch with known individuals, and that students tend to disclose more personal information about themselves on Facebook; hence attracting potential privacy risks upon themselves.     

Scheme for Generation of <Emphasis Type="Italic">W</Emphasis> and <Emphasis Type="Italic">W</Emphasis>-like States of Nonidentical Particles and their Application in Teleportation

In this paper, a scheme is proposed for the preparation of the tripartite W state or W-like state of nonidentical particles. In our scheme, our required resources include two atoms and one cavity field, which makes our system become simple. Because each party included by W state has its own two possible states, and is not identical each other, one can easily distinguish them. Furthermore, we teleportate an unknown state of cavity field by using this W state as quantum channels. Our scheme of preparation employing a single high-Q superconducting cavity turns out to be attractive to realize based on present or future cavity QED techniques. Partially supported by Natural Science Foundation of Jiangxi, China, under Grant No. 0612006 and by the Scientific Research Foundation of Jiangxi Provincial Department of Education, China, under Grant No. [2007]191.     

On “Babbage and Kings” and “How sausage wasmade”: and now for the rest of the story

A letter dated April 27, 1835 from Charles Babbage to Adolphe Quetelet has been identified as the earliest known reference to the Analytical Engine. The letter was later translated into French and published in the Bulletin of the Royal Academy of Sciences in Brussels in May 1935, and then once again translated back to English to appear in Scientific Memoirs edited by Richard and John E. Taylor in 1843. A 1983 paper by Alfred van Sinderen in the Annals discussed the letter in its 1835 and 1843 reprints, but stated that “the original is not known to exist. ” Herman Berg, a part-time student at the University of Michigan, located the original April 1835 letter in the archives of the Royal Academy, and has since claimed some measure of “intellectual ownership” of the letter. The story of his failures to get the reports of his “find” published in the history of computing literature and the lack of acknowledgment of the “find” in other publications led Michael David, Illinois institute of Technology, to publish two other papers charging the editors and authors of the Annals and the editors of the “Works of Charles Babbage” with forms of plagiarism. This report is a response to those charges     

‘A or B’ to ‘A and B’

nal responses to such situations predominantly involve trade–off and compromise. This either/or thinking style almost invariably leads to lose–lose outcomes. This in turn despite the inordinate amount of literature and methodology available for ‘optimising’ those outcomes. Highly fashionable talk of ‘third ways’ or ‘win–win’ or ‘A and B’ solutions are an emerging counter to such thinking. Unfortunately, the literature–base for such approaches is largely non–existent, and hence win–win remains as precisely fashionable talk to most observers. This paper discusses the positive role TRIZ may be expected to play in beginning the task of turning win–win from nice idea to practical reality. Mass–customization is used as an exemplar contradiction problem.