950 resultados para -Compact categories
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If C is a stable model category with a monoidal product then the set of homotopy classes of self-maps of the unit forms a commutative ring, [S,S]C. An idempotent e of this ring will split the homotopy category: [X,Y]Ce[X,Y]C(1e)[X,Y]C. We prove that provided the localised model structures exist, this splitting of the homotopy category comes from a splitting of the model category, that is, C is Quillen equivalent to LeSCL(1e)SC and [X,Y]LeSCe[X,Y]C. This Quillen equivalence is strong monoidal and is symmetric when the monoidal product of C is.
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The Millennium Challenge Corporation (MCC) contracted the Technology & Social Change group (TASCHA) at the University of Washington to conduct a performance evaluation of the Namibia Regional Study and Resource Centers (RSRC) Activity. This evaluation has been designed to serve the needs of two major stakeholders, MCC and the Namibia Library and Archives Service (NLAS). The evaluation comprises a set of quantitative and qualitative data collection efforts divided into two categories: Component 1 and Component 2. This report presents the findings for Component 1 only, focusing on evaluating the RSRC planning and implementation activities leading up to the end of the MCA-Namibia Compact in September 2014.
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Les proprits hydrauliques dun till du Nord du Qubec en condition sature et non sature ont t tudies en laboratoire laide de lessai de conductivit hydraulique et lessai de succion qui permet dobtenir la courbe de rtention deau. Les essais ont t raliss avec des chantillons compacts sous diffrentes conditions de teneur en eau et de masse volumique sche, de manire valuer linfluence de ces conditions sur les proprits hydrauliques. Les tudes prcdentes ont montr quune structure agrge se dveloppe dans le till lorsquil est compact de ct sec de loptimum Proctor, cest--dire un degr de saturation de compactage infrieur au degr de saturation optimum (Sr0 < Sr-opt). Le till tudi dans le cadre de cette tude diffre de ceux utiliss dans les tudes prcdentes par son trs faible pourcentage de particules argileuses (< 2 m) de 0,7%. Lobjectif principal de cette tude est dvaluer linfluence des conditions de compactage sur la conductivit hydraulique et la courbe de rtention deau et de dterminer si une structure agrge se dveloppe lorsque le till est compact du ct sec de loptimum. Les rsultats exprimentaux typiques de la conductivit hydraulique sature obtenus pour les chantillons compacts du ct humide de loptimum (Sr0 > Sr-opt) avec un indice des vides de 0,328 varient de 2,6 x 10-7 8,6 x 10-7 m/s. Les conductivits hydrauliques typiques obtenues pour les chantillons compacts du ct sec de loptimum (Sr0 < Sr-opt) avec le mme indice des vides taient trs similaires, variant entre 2,4 x 10-7 et 9,1 x 10-7 m/s. Les courbes de rtention deau mesures en laboratoire sont trs semblables entre elles, prsentant toutes une structure de sol homogne, peu importe si lchantillon a t compact du ct sec ou du ct humide. Il apparait que la conductivit hydraulique et la courbe de rtention deau de ce till sont trs peu influences par le degr de saturation de compactage. Ceci peut tre expliqu par le trs faible pourcentage de particules argileuses, qui prvient la formation dagrgations de particules dans la structure du till lorsquil est compact du ct sec de loptimum Proctor. Plusieurs modles destimation de la conductivit hydraulique sont utiliss. Cette tude propose trois nouveaux modles destimation de la conductivit hydraulique sature pour les tills du Nord du Qubec. Le premier modle met en relation la conductivit hydraulique sature avec le diamtre des grains de la fraction fine (d50 FF) et le deuxime modle est une quation modifie de Kozeny-Carman et Hazen base sur la porosit et une taille de particule effective (d10). Finalement, un modle permettant dvaluer leffet de lagrgation avec lquation de Kozeny-Carman modifie dans les tills compacts est propos.
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Languages based upon binary relations offer an appealing setting for constructing programs from specifications. For example, working with relations rather than functions allows specifications to be more abstract (for example, many programs have a natural specification using the converse operator on relations), and affords a natural treatment of non-determinism in specifications. In this paper we present a novel pictorial interpretation of relational terms as simple pictures of circuits, and a soundness/completeness result that allows relational equations to be proved by pictorial reasoning.
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The aim of this thesis was to observe possibilities to enhance the development of manufacturing costs savings and competitiveness related to the compact KONE Renova Slim elevator door. Compact slim doors are especially designed for EMEA markets. EMEA market area is characterized by highly competitive pricing and lead times which are manifested as pressures to decrease manufacturing costs and lead times of the compact elevator door. The new elevator safety code EN81-20 coming live during the spring 2016 will also have a negative impact on the cost and competitiveness development making the situation more acute. As a sheet metal product the KONE Renova slim is highly variable. Manufacturing methods utilized in the production are common and robust methods. Due to the low volumes, high variability and tight lead times the manufacturing of the doors is facing difficulties. Manufacturing of the doors is outsourced to two individual suppliers Stera and Wittur. This thesis was implemented in collaboration with Stera. KONE and Stera pursue a long term and close partnership where the benefits reached by the collaboration are shared equally. Despite the aims, the collaboration between companies is not totally visible and various barriers are hampering the development towards more efficient ways of working. Based on the empirical studies related to this thesis, an efficient standardized (A+) process was developed for the main variations of the compact elevator door. Using the standardized process KONE is able to order the most important AMDS door variations from Stera with increased quality, lower manufacturing costs and manufacturing lead time compared to the current situation. In addition to all the benefits, the standardized (A+) process also includes risks in practice. KONE and the door supplier need to consider these practical risks together before decisions are made.
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There are two main aims of the paper. The first one is to extend the criterion for the precompactness of sets in Banach function spaces to the setting of quasi-Banach function spaces. The second one is to extend the criterion for the precompactness of sets in the Lebesgue spaces $L_p(\Rn)$, $1 \leq p < \infty$, to the so-called power quasi-Banach function spaces. These criteria are applied to establish compact embeddings of abstract Besov spaces into quasi-Banach function spaces. The results are illustrated on embeddings of Besov spaces $B^s_{p,q}(\Rn)$, $0<s<1$, $0<p,q\leq \infty$, into Lorentz-type spaces.
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The topic of this thesis is the application of distributive laws between comonads to the theory of cyclic homology. The work herein is based on the three papers 'Cyclic homology arising from adjunctions', 'Factorisations of distributive laws', and 'Hochschild homology, lax codescent,and duplicial structure', to which the current author has contributed. Explicitly, our main aims are: 1) To study how the cyclic homology of associative algebras and of Hopf algebras in the original sense of Connes and Moscovici arises from a distributive law, and to clarify the role of different notions of bimonad in this generalisation. 2) To extend the procedure of twisting the cyclic homology of a unital associative algebra to any duplicial object defined by a distributive law. 3) To study the universality of Bohm and Stefans approach to constructing duplicial objects, which we do in terms of a 2-categorical generalisation of Hochschild (co)homology. 4) To characterise those categories whose nerve admits a duplicial structure.
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International audience
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The Internet has grown in size at rapid rates since BGP records began, and continues to do so. This has raised concerns about the scalability of the current BGP routing system, as the routing state at each router in a shortest-path routing protocol will grow at a supra-linearly rate as the network grows. The concerns are that the memory capacity of routers will not be able to keep up with demands, and that the growth of the Internet will become ever more cramped as more and more of the world seeks the benefits of being connected. Compact routing schemes, where the routing state grows only sub-linearly relative to the growth of the network, could solve this problem and ensure that router memory would not be a bottleneck to Internet growth. These schemes trade away shortest-path routing for scalable memory state, by allowing some paths to have a certain amount of bounded stretch. The most promising such scheme is Cowen Routing, which can provide scalable, compact routing state for Internet routing, while still providing shortest-path routing to nearly all other nodes, with only slightly stretched paths to a very small subset of the network. Currently, there is no fully distributed form of Cowen Routing that would be practical for the Internet. This dissertation describes a fully distributed and compact protocol for Cowen routing, using the k-core graph decomposition. Previous compact routing work showed the k-core graph decomposition is useful for Cowen Routing on the Internet, but no distributed form existed. This dissertation gives a distributed k-core algorithm optimised to be efficient on dynamic graphs, along with with proofs of its correctness. The performance and efficiency of this distributed k-core algorithm is evaluated on large, Internet AS graphs, with excellent results. This dissertation then goes on to describe a fully distributed and compact Cowen Routing protocol. This protocol being comprised of a landmark selection process for Cowen Routing using the k-core algorithm, with mechanisms to ensure compact state at all times, including at bootstrap; a local cluster routing process, with mechanisms for policy application and control of cluster sizes, ensuring again that state can remain compact at all times; and a landmark routing process is described with a prioritisation mechanism for announcements that ensures compact state at all times.
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"TID-26500/R1. Distribution category: UC-2."
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Object recognition has long been a core problem in computer vision. To improve object spatial support and speed up object localization for object recognition, generating high-quality category-independent object proposals as the input for object recognition system has drawn attention recently. Given an image, we generate a limited number of high-quality and category-independent object proposals in advance and used as inputs for many computer vision tasks. We present an efficient dictionary-based model for image classification task. We further extend the work to a discriminative dictionary learning method for tensor sparse coding. In the first part, a multi-scale greedy-based object proposal generation approach is presented. Based on the multi-scale nature of objects in images, our approach is built on top of a hierarchical segmentation. We first identify the representative and diverse exemplar clusters within each scale. Object proposals are obtained by selecting a subset from the multi-scale segment pool via maximizing a submodular objective function, which consists of a weighted coverage term, a single-scale diversity term and a multi-scale reward term. The weighted coverage term forces the selected set of object proposals to be representative and compact; the single-scale diversity term encourages choosing segments from different exemplar clusters so that they will cover as many object patterns as possible; the multi-scale reward term encourages the selected proposals to be discriminative and selected from multiple layers generated by the hierarchical image segmentation. The experimental results on the Berkeley Segmentation Dataset and PASCAL VOC2012 segmentation dataset demonstrate the accuracy and efficiency of our object proposal model. Additionally, we validate our object proposals in simultaneous segmentation and detection and outperform the state-of-art performance. To classify the object in the image, we design a discriminative, structural low-rank framework for image classification. We use a supervised learning method to construct a discriminative and reconstructive dictionary. By introducing an ideal regularization term, we perform low-rank matrix recovery for contaminated training data from all categories simultaneously without losing structural information. A discriminative low-rank representation for images with respect to the constructed dictionary is obtained. With semantic structure information and strong identification capability, this representation is good for classification tasks even using a simple linear multi-classifier.
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The premise of automated alert correlation is to accept that false alerts from a low level intrusion detection system are inevitable and use attack models to explain the output in an understandable way. Several algorithms exist for this purpose which use attack graphs to model the ways in which attacks can be combined. These algorithms can be classified in to two broad categories namely scenario-graph approaches, which create an attack model starting from a vulnerability assessment and type-graph approaches which rely on an abstract model of the relations between attack types. Some research in to improving the efficiency of type-graph correlation has been carried out but this research has ignored the hypothesizing of missing alerts. Our work is to present a novel type-graph algorithm which unifies correlation and hypothesizing in to a single operation. Our experimental results indicate that the approach is extremely efficient in the face of intensive alerts and produces compact output graphs comparable to other techniques.
