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关键词： Image segmentation   Head   Training   Manifolds   Semantics   Computer science   Neural networks   Fully convolutional network (FCN)   hierarchical models   semisupervised learning  

摘要： This article presents a semisupervised multilabel fully convolutional network (FCN) for hierarchical object parsing of images. We consider each object part (e.g., eye and head) as a class label and learn to assign every image pixel to multiple coherent part labels. Different from previous methods that consider part labels as independent classes, our method explicitly models the internal relationships between object parts, e.g., that a pixel highly scored for eyes should be highly scored for heads as well. Such relationships directly reflect the structure of the semantic space and thus should be respected while learning the deep representation. We achieve this objective by introducing a multilabel softmax loss function over both labeled and unlabeled images and regularizing it with two pairwise ranking constraints. The first constraint is based on a manifold assumption that image pixels being visually and spatially close to each other should be collaboratively classified as the same part label. The other constraint is used to enforce that no pixel receives significant scores from more than one label that are semantically conflicting with each other. The proposed loss function is differentiable with respect to network parameters and hence can be optimized by standard stochastic gradient methods. We evaluate the proposed method on two public image data sets for hierarchical object parsing and compare it with the alternative parsing methods. Extensive comparisons showed that our method can achieve state-of-the-art performance while using 50% less labeled training samples than the alternatives.

关键词： Games   Training   Tools   Computer security   Computer science   Computer networking education   cyber education   serious games  

摘要： Cyberspace odyssey (CSO) is a novel serious game supporting computer networking education by engaging students in a race to successfully perform various cybersecurity tasks in order to collect clues and solve a puzzle in virtual near-Earth three-dimensional space. Each team interacts with the game server through a dedicated client presenting a multimodal interface, using a game controller for navigation and various desktop computer networking tools of the trade for cybersecurity tasks on the game's physical network. Specifically, teams connect to wireless access points, use packet monitors to intercept network traffic, decrypt and reverse engineer that traffic, craft well-formed and meaningful responses, and transmit those responses. Successful completion of these physical network actions to solve a sequence of increasingly complex problems is necessary to progress through the virtual story-driven adventure. Use of the networking tools reinforces networking theory and offers hands-on practical training requisite for today's cyber operators. This article presents the learning outcomes targeted by a classroom intervention based on CSO, the design and implementation of the game, a pedagogical overview of the overall intervention, and four years of quantitative and qualitative data assessing its effectiveness.

关键词： animal liberation   children   choices   early education   environmental destruction   nonhuman animal welfare  

摘要： This article examined reasons why information pertaining to nonhuman animal welfare and liberation should be introduced during childhood. Studies indicate that animal-welfare activists' and abolitionists' efforts to date may be insufficient given the pervasive environmental destruction and ongoing animal suffering. Moreover, research reveals that education related to animal welfare and liberation is systematically excluded from children's education, and they thus remain unaware of the sources and associated health hazards of meat they consume. Conversely, children's knowledge about animal welfare increases when exposed to literature on the topic, which enables them to make informed choices regarding meat consumption. This paper draws on animal-welfare and liberation literature to argue that augmenting children's knowledge about animal welfare and liberation can foster children's understanding, language, philosophy, and ability to make informed choices about their relationship with animals and the environment in general.

关键词： Optimization   Adaptation models   Computational modeling   Computer science   Topology   Sociology   Statistics   Distributed evolutionary algorithms   elite-guided learning (EGL)   high-dimensional problems   large-scale optimization   particle swarm optimization (PSO)  

摘要： Large-scale optimization with high dimensionality and high computational cost becomes ubiquitous nowadays. To tackle such challenging problems efficiently, devising distributed evolutionary computation algorithms is imperative. To this end, this paper proposes a distributed swarm optimizer based on a special master-slave model. Specifically, in this distributed optimizer, the master is mainly responsible for communication with slaves, while each slave iterates a swarm to traverse the solution space. An asynchronous and adaptive communication strategy based on the request-response mechanism is especially devised to let the slaves communicate with the master efficiently. Particularly, the communication between the master and each slave is adaptively triggered during the iteration. To aid the slaves to search the space efficiently, an elite-guided learning strategy is especially designed via utilizing elite particles in the current swarm and historically best solutions found by different slaves to guide the update of particles. Together, this distributed optimizer asynchronously iterates multiple swarms to collaboratively seek the optimum in parallel. Extensive experiments on a widely used large-scale benchmark set substantiate that the distributed optimizer could: 1) achieve competitive effectiveness in terms of solution quality as compared to the state-of-the-art large-scale methods;2) accelerate the execution of the algorithm in comparison with the sequential one and obtain almost linear speedup as the number of cores increases;and 3) preserve a good scalability to solve higher dimensional problems.

ISBN: (纸本)9787115535122

关键词： murder   capital punishment   race   gender   historical criminology  

摘要： This article examines 10 capital cases of men of colour sentenced to death in England and Wales for intimate murders of white British women during 1900-39. It argues that such cases enable analysis of the prevailing emotional norms of this era and the ways in which these were shaped by race, gender and class. Perceptions of intimate relationships as legitimate or illegitimate-judgments about who should feel what about whom-'is' related to understandings of citizenship. In revealing the emotional norms at play in cases of murder, it is possible to illustrate how the criminal justice system governed through emotion.

摘要： This article explores the history of Ayuba Sulieman Diallo, a West African Muslim enslaved in Maryland in 1731 and it takes a critical look at his portrait by the English painter, William Hoare in 1733. He was the first documented Muslim slave to return to Africa (Bundu in Senegal) in 1734. Charles H. Long's concept of signification (the issue of naming and identity) and the theme of intellectual resistance to enslavement are the analytical keys to understanding Diallo's resistance strategies. By signification, Long refers to the process by which white Americans and Europeans constructed names, stereotypes, and racial categories for people of African descent during the western exploration and conquest of the world that began with Christopher Columbus's voyage in 1492; and he examines the subaltern identities and strategies that the enslaved embraced in their freedom struggles against the systemic racism of the majority community. The main argument of the article is that the painting by Hoare exemplifies how this aspect of visual culture signified Ayuba Suleiman Diallo as a new type of free and literate Muslim during this particular moment of the 18th century black Atlantic world. I therefore contend that his portrait became a transnational symbol of the religious legacy of enslaved African Muslims who maintained their faith and resisted Christianization in the United States.

关键词： Computer science   Peer group norms   Intragroup dynamics   Peer evaluation   Gender stereotypes   STEM  

摘要： Women are drastically underrepresented within computer science, which is in part informed by societal ideas of who can and should belong in the sciences. Less is known about how children evaluate their peers who challenge gendered expectations of who can and should take part in computer science. The current study asked children (N = 213;110 girls) in middle childhood (M-age = 8.71 years;n = 108) and late childhood (M-age = 10.56 years;n = 105) to evaluate a gender-matched peer who challenged a group norm related to either computer science (male-gendered domain) or biology (less male-gendered domain). Male participants most negatively evaluated a peer who wanted to take part in a biology activity when the rest of the group wanted to do a programming activity. Furthermore, male participants expected their group to negatively evaluate this deviant peer in the programming condition. Mediation analysis revealed that for boys in the computer science condition, perceived group evaluation predicted individual evaluation. Female participants, in contrast, did not negatively evaluate someone who challenged a STEM (science, technology, engineering, and math) peer group norm. This study demonstrates that male peer groups may perpetuate the idea that computer science is for men through negative evaluation of in-group members who challenge those ideas and, in turn, maintain their dominant position as the high-status group. Achieving equity in the computer science field will require a greater understanding of these peer group norms. (C) 2020 The Authors. Published by Elsevier Inc.

关键词： Decision trees   Partitioning algorithms   IP networks   Computer science   Software algorithms   Memory management   Complexity theory   Packet classification   SDN   openflow   open vswitch   virtualization  

摘要： Software switches are being deployed in SDN to enable a wide spectrum of non-traditional applications. The popular Open vSwitch uses a variant of Tuple Space Search (TSS) for packet classifications. Although it has good performance on rule updates, it is less efficient than decision trees on lookups. In this paper, we propose a two-stage framework consisting of heterogeneous algorithms to adaptively exploit different characteristics of the rule sets at different scales. In the first stage, partial decision trees are constructed from several rule subsets grouped with respect to their small fields. This grouping eliminates rule replications at large scales, thereby enabling very efficient pre-cuttings. The second stage handles packet classification at small scales for non-leaf terminal nodes, where rule replications within each subspace may lead to inefficient cuttings. A salient fact is that small space means long address prefixes or less nesting levels of ranges, both indicating a very limited tuple space. To exploit this favorable property, we employ a TSS-based algorithm for these subsets following tree constructions. Experimental results show that our work has comparable update performance to TSS in Open vSwitch, while achieving almost an order-of-magnitude improvement on classification performance over TSS.