To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
In this paper we introduce stable systems of inclusions, which feature chosen arrows A ↪ B to capture the notion that A is a subobject of B, and proposes them as an alternative context to stable systems of monics to discuss partiality. A category C equipped with such a system $\mathscr{I}$, called an i-category, is shown to give rise to an associated category ∂(C,$\mathscr{I}$) of partial maps, which is a split restriction category whose restriction monics are inclusions. This association is the object part of a 2-equivalence between such inclusively split restriction categories and i-categories. $\mathscr{I}$ determines a stable system of monics $\mathscr{I}$+ on C, and, conversely, a stable system of monics $\mathscr{M}$ on C yields an i-category (C[$\mathscr{M}$],$\mathscr{M}$+), giving a 2-adjunction between i-categories and m-categories. The category of partial maps Par(C,$\mathscr{M}$) is isomorphic to the full subcategory of ∂(C[$\mathscr{M}$],$\mathscr{M}$+) comprising the objects of C, and ∂(C,$\mathscr{I}$) ≅ Par(C,$\mathscr{I}$+).
Continuous lattices were characterised by Martín Escardó as precisely those objects that are Kan-injective with respect to a certain class of morphisms. In this paper we study Kan-injectivity in general categories enriched in posets. As an example, ω-CPO's are precisely the posets that are Kan-injective with respect to the embeddings ω ↪ ω + 1 and 0 ↪ 1.
For every class $\mathcal{H}$ of morphisms, we study the subcategory of all objects that are Kan-injective with respect to $\mathcal{H}$ and all morphisms preserving Kan extensions. For categories such as Top0 and Pos, we prove that whenever $\mathcal{H}$ is a set of morphisms, the above subcategory is monadic, and the monad it creates is a Kock–Zöberlein monad. However, this does not generalise to proper classes, and we present a class of continuous mappings in Top0 for which Kan-injectivity does not yield a monadic category.
We developed an efficient semisupervised feedforward neural network clustering model with one epoch training and data dimensionality reduction ability to solve the problems of low training speed, accuracy, and high memory complexity of clustering. During training, a codebook of nonrandom weights is learned through input data directly. A standard weight vector is extracted from the codebook, and the exclusive threshold of each input instance is calculated based on the standard weight vector. The input instances are clustered based on their exclusive thresholds. The model assigns a class label to each input instance through the training set. The class label of each unlabeled input instance is predicted by considering a linear activation function and the exclusive threshold. Finally, the number of clusters and the density of each cluster are updated. The accuracy of the proposed model was measured through the number of clusters and the quantity of correctly classified nodes, which was 99.85%, 100%, and 99.91% of the Breast Cancer, Iris, and Spam data sets from the University of California at Irvine Machine Learning Repository, respectively, and the superior F measure results between 98.29% and 100% accuracies for the breast cancer data set from the University of Malaya Medical Center to predict the survival time.
The minimum roman dominating problem (denoted by γR(G),the weight of minimum roman dominating function of graph G) is a variant of the verywell known minimum dominating set problem (denoted by γ(G), thecardinality of minimum dominating set of graph G). Both problems remain NP-Complete when restrictedto P5-free graph class [A.A. Bertossi,Inf. Process. Lett. 19 (1984) 37–40; E.J. Cockayne,et al. Discret. Math. 278 (2004) 11–22]. In this paper westudy both problems restricted to some subclasses of P5-free graphs.We describe robust algorithms that solve both problems restricted to (P5,(s,t)-net)-free graphsin polynomial time. This result generalizes previous works for both problems, and improvesexisting algorithms when restricted to certain families such as (P5,bull)-freegraphs. It turns out that the same approach also serves to solve problems for generalgraphs in polynomial time whenever γ(G) and γR(G)are fixed (more efficiently than naive algorithms). Moreover, the algorithms described areextremely simple which makes them useful for practical purposes, and as we show in thelast section it allows to simplify algorithms for significant classes such ascographs.
We describe the C2k+1-free graphs on n vertices with maximum number of edges. The extremal graphs are unique for n ∉ {3k − 1, 3k, 4k − 2, 4k − 1}. The value of ex(n, C2k+1) can be read out from the works of Bondy [3], Woodall [14], and Bollobás [1], but here we give a new streamlined proof. The complete determination of the extremal graphs is also new.
We obtain that the bound for n0(C2k+1) is 4k in the classical theorem of Simonovits, from which the unique extremal graph is the bipartite Turán graph.
We describe an online database of number fields which accompanies this paper. The database centers on complete lists of number fields with prescribed invariants. Our description here focuses on summarizing tables and connections to theoretical issues of current interest.
A central result in extremal set theory is the celebrated theorem of Sperner from 1928, which gives the size of the largest family of subsets of [n] not containing a 2-chain, F1 ⊂ F2. Erdős extended this theorem to determine the largest family without a k-chain, F1 ⊂ F2 ⊂ . . . ⊂ Fk. Erdős and Katona, followed by Kleitman, asked how many chains must appear in families with sizes larger than the corresponding extremal bounds.
In 1966, Kleitman resolved this question for 2-chains, showing that the number of such chains is minimized by taking sets as close to the middle level as possible. Moreover, he conjectured the extremal families were the same for k-chains, for all k. In this paper, making the first progress on this problem, we verify Kleitman's conjecture for the families whose size is at most the size of the k + 1 middle levels. We also characterize all extremal configurations.
This paper presents a new approach to accurately track a moving vehicle with a multiview setup of red–green–blue depth (RGBD) cameras. We first propose a correction method to eliminate a shift, which occurs in depth sensors when they become worn. This issue could not be otherwise corrected with the ordinary calibration procedure. Next, we present a sensor-wise filtering system to correct for an unknown vehicle motion. A data fusion algorithm is then used to optimally merge the sensor-wise estimated trajectories. We implement most parts of our solution in the graphic processor. Hence, the whole system is able to operate at up to 25 frames per second with a configuration of five cameras. Test results show the accuracy we achieved and the robustness of our solution to overcome uncertainties in the measurements and the modelling.
This special issue comprises selected papers which were presented at the workshop on dependently typed programming (DTP 10) in Edinburgh in July 2010 – affiliated with Federated Logic conferences (FLOC 10). Earlier workshops on dependently typed programming took place in Nottingham in 2008 (DTP 2008) and there also has been a Dagstuhl seminar (04381) on this subject in 2004. After DTP 2010, in 2011 a workshop on dependently typed programming (DTP 11) took place in Nijmegen affiliated with Interactive Theorem Proving 2011 (ITP 11). In September 2011 there also was a DTP workshop in Shonan, Japan.
The decision on the overall functionality to provide with a car is first of all a marketing decision and independent of the in-car networking technologies used and available. However, as soon as decisions have to be made on how to enable the functionality, in-car networking becomes important. Aspects like flexibility, scalability, or how to distribute functions are severely impacted by the properties of in-car networking. This chapter thus discusses the opportunities and changes Automotive Ethernet brings to system development.
A brief overview of the system development process
The development process in automotive follows the V-cycle. While Section 2.3.1 used the V-cycle to explain the responsibilities shared between car manufacturer and Tier 1 supplier, in this section the model is used to explain the changes the introduction of Ethernet-based communication brings to the development process. The important idea of the V-cycle is to follow a top-down approach on the development side and a bottom-up approach on the test side. On both sides, each new step requires the conclusion of the previous. During the development, the later need for testing is directly supported with the provision of test cases. This ensures stringent test coverage.
On 11 November 2013, I [Kirsten Matheus] attended a celebration of 40 years since the invention of Ethernet at an IEEE 802 plenary meeting. During the celebration Robert Metcalfe, David Boggs, Ronald Crane, and Geoff Thompson were honoured as the pioneers of Ethernet. If I had to name the people without whom Automotive Ethernet would not have happened, I would name Thomas Königseder, technical expert at BMW and co-author of this book, and Neven Pischl, EMC expert at Broadcom.
It all started in 2004, when Thomas received the responsibility for speeding up the software flash process for BMW cars. With the CAN interface used at the time, flashing the 1 Gbyte of data anticipated for 2008 would have required 16 hours to complete. After careful evaluation, Thomas chose and enabled the use of standard 100BASE-TX Ethernet for this purpose. Thus in 2008 the first serial car with an Ethernet interface, a BMW 7-series, was introduced to the world.
An explanation of the needs, the development, and some of the choices in in-car networking starts with the windows. When automobiles were invented they were simply machines on wheels without windows. It was only later that windows were added, first at the front, then at the sides and back. The windows were static or insertable in one piece. This obviously was not very comfortable, neither for the handling of the windows, nor for the temperature regulation in the passenger cabin. Thus, in 1928 the first mechanical window winder, able to hold a window at any position desired, was presented to the public [1]. The first power windows were introduced in 1941 [2]. BMW was the first company to introduce power windows in Europe and the first BMW with all electric power windows was a “Serie 2 BMW 503,” which had an SOP at the end of 1957 [3]. This is where it gets interesting.
It is quite straightforward to imagine a switch in a vehicle door that actuates the electric motor for a window located in the same door. Everything is in one physical location and the wiring will be short. The wiring gets longer when all movable windows are required to be controllable by the driver, in addition to the “local” control in every door. More wiring between almost exactly the same locations is needed if a central door lock plus an electronic side mirror adjustment are also discretely wired. Figure 2.1(a) indicates that with only the basic comfort functions the size, weight, and number of wires will soon become prohibitive. In the case of discrete wiring, inventiveness quickly circles around the question of “How is it possible to fit another wire onto this inline connector or through this opening between e.g. body and door?” instead of fully exploring the possibilities of creating a new feature. On top of this, large wiring bundles are not only heavy, costly, and hard to install, but also error prone and difficult to diagnose [4].
To understand physical transmission in in-car networks two aspects are important: the actual automotive environment in which the communication happens and how the properties of the PHY technology ensure its use in this environment. This chapter will therefore start with the PHY technologies in Section 4.1, explain the automotive channel in Section 4.2, and discuss ElectroMagnetic Compatibility (EMC) in Section 4.3. Other important requirements in this context, such as semiconductor quality, Power over Data Line (PoDL), and Energy Efficient Ethernet (EEE), are introduced in Section 4.4.
The Physical Layer (PHY) technology
100 Mbps BroadR-Reach (OABR)
It all started with the IEEE 802.3 1000BASE-T standard. During its development, the engineers at Broadcom learned to handle the communication challenges that needed to be mastered for such a high data rate transmission. So when Ethernet in the First Mile (EFM) was being developed at IEEE, Broadcom reused some of the basic principles of 1000BASE-T for a suitable solution: instead of four pairs of wiring one pair was used and the channel coding was made more robust, so that it was possible to transmit 100 Mbps data over a worse, i.e. longer, channel. IEEE standardized a different solution for EFM, while Broadcom proposed their technology for EFM in China [1]. When BMW was looking for an Ethernet solution suitable for automotive another interesting use case was found for the Broadcom technology.
In 1969 employees at AT&T/Bell Labs developed the first version of Unix. The original intention was to aid the company’s internal development of software on and for multiple platforms, but over time Unix evolved to be a very widespread and powerful operating system, which facilitated distributed computing. An important reason for the successful proliferation of Unix was that for antitrust reasons AT&T was neither allowed to sell Unix nor to keep the intellectual property to itself [1]. In consequence Unix – in source code – was shared with everybody interested.
It was especially, but not only, embraced by universities and the community that evolved provided the basis for the computing environment we are used to today and in which also Ethernet has its place. At a time when computing was dominated by large, proprietary, and very expensive mainframe computers few people could use, Unix created a demand for Local Area Networking (LAN) while at the same time providing an affordable, common platform for developing it [2]. As one example, a group at the University of California, Berkeley created a Unix derivative. The Berkeley Software Distribution (BSD) was first released in 1978 and its evolutions became as established as the “BSD-style license” attached to it [3]. Another example is the TCP protocol. The first version of this, published in 1974, was implemented for Unix by the University of Stanford by 1979 [4]. Later in 1989, the then up-to-date TCP/IP code for Unix from AT&T was placed in the public domain and thus significantly helped to distribute the TCP/IP Internet Protocol Suite [5].