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We investigate methods for detection of rapid workload increases (load spikes) for cloud workloads. Such rapid and unexpected workload spikes are a main cause for poor performance or even crashing applications as the allocated cloud resources become insufficient. To detect the spikes early is fundamental to perform corrective management actions, like allocating additional resources, before the spi

A semantic editor, providing services like completion and code browsing, can help users to quickly develop high-quality source code. However, a lot of languages still lack semantic editor support due to the difficulty and costs of development. Tool generation and reuse can greatly alleviate this development task. Specifically, tool generation from a formal specification, such as reference attribut

The number of applications in computer vision that model higher-order interactions has exploded over the last few years. The standard technique for solving such problems is to reduce the higher-order objective function to a quadratic pseudo-boolean function, and then use roof duality for obtaining a lower bound. Roof duality works by constructing the tightest possible lower-bounding submodular fun

The problem of communicating one bit over a memoryless Gaussian channel with an energy constraint is discussed. It is assumed that the channel is allowed to be used only two times. An ideal feedback channel is also supposed available. The optimal feedback strategy and the bit-error probability are derived. It is shown that feedback gives a significant performance gain and that the optimal strategy

Machining processes in the industry of today are rarely performed using industrial robots. In the cases where robots are used, machining is often performed using position control with a conservative feed-rate, to avoid excessive process forces. There is a great benefit in controlling the process forces instead, so as to improve the time-efficiency by applying the maximum allowed force, and thus re

We find good rate 2/3 and 3/4 convolutional codes for use with iterative decoding (turbo equalization) of coded intersymbol interference with AWGN. The method is based on the input-output bit error rate characteristic of the convolutional BCJR decoder module. An analysis leads to an equivalent minimum distance under the required intrinsic subtraction, which depends on free distance and an input-ou

Creation and adoption of corporate policies requires significant commitment of scarce senior management resources. In the absence of processes and tools, convergence upon final policy and may not be achieved in a timely manner. Significant similarities between policy and requirements documents suggest that requirements engineering techniques could be used to generate policy. However, neither evide

In this paper, we give an overview of spatially coupled turbo codes (SC-TCs), the spatial coupling of parallel and serially concatenated convolutional codes, recently introduced by the authors. For presentation purposes, we focus on spatially coupled serially concatenated codes (SC-SCCs). We review the main principles of SC-TCs and discuss their exact density evolution (DE) analysis on the binary

Multipath routing gives traffic demands an opportunity to use multiple paths through a network. In a single-demand situation, its benefits are easy to see. In a multi-commodity case, when potentially all node-pairs (demands) generate traffic, they compete for the same network resources. In this work, we consider multipath routing in communication networks in a multi-commodity setting from a traffi

This work presents an extension of a design procedure for dynamic output feedback design for systems with nonlinearities satisfying quadratic constraints. In this work we used an axial gas compressor model described by the 3-state Moore-Greitzer compressor model (MG) that has some challenges for output feedback control design (Planovsky and Nikolaev 1990), (Rubanova 2013). The more general constra

In color-based detection methods, varying illumination often causes problems, since an object may be perceived to have different colors under different lighting conditions. In the field of color constancy this is usually handled by estimating the illumination spectrum and accounting for its effect on the perceived color. In this paper a method for designing a robust classifier is presented, i.e.,

Analog decoders are constructed based on interconnecting CMOS Gilbert vector multipliers using transistors operating in the sub-VT region. They are seen as an interesting alternative to digital implementations with a low transistor count and a potential for a very low power consumption. Analog implementation makes the circuit sensitive to mismatch, requiring careful transistor sizing. A simulation

In this paper we prove threshold saturation for spatially coupled turbo codes (SC-TCs) and braided convolutional codes (BCCs) over the binary erasure channel. We introduce a compact graph representation for the ensembles of SC-TC and BCC codes which simplifies their description and the analysis of the message passing decoding. We demonstrate that by few assumptions in the ensembles of these codes,

Signal-to-noise ratio (SNR) estimation is commonly used in wireless receivers to enhance the performance in different ways. In this paper a novel low complexity SNR estimator for OFDM is proposed. The estimator might be implemented using floating point representation or by using only the sign-bit, and can if desired be effectively implemented by reconfiguring the standard correlator used for time-

In the emerging Delay Tolerant Networks (DTNs) content dissemination platform, mobile nodes opportunistically exchange content as they meet, with the intent of sharing content among nodes with common interests. During a meeting, nodes can exchange both content of direct interest to themselves as well as content that is of interest to a larger set of nodes that may be encountered in the future. The

A suturing including knot tying is one of the more difficult operations to learn in telesurgical systems. Apprentice surgeons commonly suffer from suture breakage or knot failure. The difficulty, generally, comes from the absence of feedback of interaction force cues in a medical device (e.g., a needle and a thread) . Even if there is haptic feedback to the operator, the operator may have a diffic

Reference attribute grammars (RAGs) can be used to express semantics as super-imposed graphs on top of abstract syntax trees (ASTs). A RAG-based AST can be used as the in-memory model providing semantic information for software language tools such as compilers, refactoring tools, and meta- modeling tools. RAG performance is based on dynamic attribute evaluation with caching. Caching all attributes

This paper investigates both positional dependence in systems with friction and the influence an increase in temperature has on the friction behavior. The positional dependence is modeled with a Radial Basis Function network and the temperature dependence is modeled as a first order system with the power loss due to friction as input, eliminating the need for temperature sensing. The proposed meth