We developed the project risk rating (PRR) for telecommunication companies. It provides qualitative risk scores assessment of capital expenditures (capex) projects to rank them by severity of exposures, to check their fit into the company’s risk profile and, ultimately, to combine projects into the efficient project portfolio with the lowest risk given return. We discussed the definition, functions and advantages of investment controlling and presented the reference model of its main subsystem – project portfolio controlling responsible for building the efficient capex project portfolio. Then, we developed the model of PRR; worked out the example of PRR’s scorecard and discussed the advantages of the PRR over the existing risk assessment tools in project portfolio management.
Finite state transducers over semigroups can be regarded as a formal model of sequential reactive programs. In this paper we introduce a uniform tech- nique for checking eectively functionality, k-valuedness, equivalence and inclusion for this model of computation in the case when a semigroup these transducers op- erate over is embeddable in a decidable group.
Let G = (V,E) be a digraph with disjoint sets of sources S ⊂ V and sinks T ⊂ V endowed with an S–T flow f : E → Z+. It is a well-known fact that f decomposes into a sum_st(fst) of s–t flows fst between all pairs of sources s ∈ S and sinks t ∈ T . In the usual RAM model, such a decomposition can be found in O(E log V 2 E ) time. The present paper concerns the complexity of this problem in the external memory model (introduced by Aggarwal and Vitter). The internal memory algorithm involves random memory access and thus becomes inefficient. We propose two novel methods. The first one requires O(Sort(E) log V 2 E ) I/Os and the second one takes O(Sort(E) log U) expected I/Os (where U denotes the maximum value of f).
We consider optimization methods for convex minimization problems under inexact information on the objective function. We introduce inexact model of the objective, which as a particular cases includes inexact oracle  and relative smoothness condition . We analyze gradient method which uses this inexact model and obtain convergence rates for convex and strongly convex problems. To show potential applications of our general framework we consider three particular problems. The first one is clustering by electorial model introduced in . The second one is approximating optimal transport distance, for which we propose a Proximal Sinkhorn algorithm. The third one is devoted to approximating optimal transport barycenter and we propose a Proximal Iterative Bregman Projections algorithm. We also illustrate the practical performance of our algorithms by numerical experiments.
Development of new HPC architectures proceeds faster than the corresponding adjustment of the algorithms for such fundamental mathematical models as quantum and classical molecular dynamics. There is the need for clear guiding criteria for the computational efficiency of a particular model on a particular hardware. LINPACK benchmark alone can no longer serve this role. In this work we consider a practical metric of the time-to-solution versus the computational peak performance of a given hardware system. In this metric we compare different hardware for the CP2K and LAMMPS software packages widely used for atomistic modeling. The metric considered can serve as a universal unambiguous scale that ranges different types of supercomputers.
The paper focuses on solving the problem of hair removal in dermatology applications. The proposed hair removal algorithm is based on Gabor filtering and PDE-based image reconstruction. It also includes the edge sharpening stage using a new warping algorithm. The idea of warping is to move pixels from the neighborhood of the blurred edge closer to the edge. The proposed technique preserves the overall luminosity and textures of the image, while making the edges sharper and less noisy.
Abstract. Research and development (R&D) involves not only researchers but also many other specialists from different areas. All of them solve a variety of tasks that require comprehensive information and analytical support. This chapter discusses the major tasks arising in R&D: study of the state of the art in a given research area, prospects assessment of research fields and forecasting their development, quality assessment of scientific publications including plagiarism detection, and automated examination of proposed R&D projects. A number of informational and analytical systems have been developed to address these tasks. The main goal of this chapter is to give a review of R&D support functions of well-known and widely-used search and analytical systems and discuss information retrieval methods behind these functions. Keywords: Full-text search, information retrieval, R&D support, scientific publication, citation databases, scientometrics, exploratory search.
In recent years there have been a number of important improvements in exact color-based maximum clique solvers, which have considerably enhanced their performance. Initial vertex ordering is one strategy known to have a significant impact on the size of the search tree. Typically, a degenerate sorting by minimum degree is used; literature also reports different tiebreaking strategies. A systematic study of the impact of initial sorting in the light of new cutting-edge ideas (e.g. recoloring , selective coloring , ILS initial lower bound computation [15, 16] or MaxSAT-based pruning ) is, however, lacking. This paper presents a new initial sorting procedure and relates performance to the new mentioned variants implemented in leading solver BBMC [9, 10].
In the paper we address a challenging problem of incorporating preferences on possible shapes of an object in a binary image segmentation framework. We extend the well-known conditional random fields model by adding new variables that are responsible for the shape of an object. We describe the shape via a flexible graph augmented with vertex positions and edge widths. We derive exact and approximate algorithms for MAP estimation of label and shape variables given an image. An original learning procedure for tuning parameters of our model based on unlabeled images with only shape descriptions given is also presented. Experiments confirm that our model improves the segmentation quality in hard-to-segment images by taking into account the knowledge about typical shapes of the object.
The ORD corpus is a representative resource of everyday spoken Russian that contains about 1000 h of long-term audio recordings of daily communication made in real settings by research volunteers. ORD macro episodes are the large communication episodes united by setting/scene of communication, social roles of participants and their general activity. The paper describes annotation principles used for tagging of macro episodes, provides current statistics on communication situations presented in the corpus and reveals their most common types. Annotation of communication situations allows using these codes as filters for selection of audio data, therefore making it possible to study Russian everyday speech in different communication situations, to determine and describe various registers of spoken Russian. As an example, several high frequency word lists referring to different communication situations are compared. Annotation of macro episodes that is made for the ORD corpus is a prerequisite for its further pragmatic annotation.
The open source C++ class library GridMD for distributed computing is reviewed including its architecture, functionality and use cases. The library is intended to facilitate development of distributed applications that can be run at contemporary supercomputing clusters and standalone servers managed by Grid or cluster task scheduling middleware. The GridMD library used to be targeted at molecular dynamics and Monte-Carlo simulations but at present it can serve as a universal tool for developing distributed computing applications as well as for creating task management codes. In both cases the distributed application is represented by a single client-side executable built from a compact C++ code. In the first place the library is targeted at developing complex applications that contain many computation stages with possible data dependencies between them which can be run efficiently in the distributed environment.