Method of Selection of Appropriate Information System for Commercial Production Company

Tato práce se zabývá postupem při výběru vhodného informačního systému pro výrobně-obchodní společnost. Nejprve je provedena analýza současného stavu, na kterou navazuje návrh na požadavky zcela nového informačního systému. Jsou stanoveny i požadavky na jeho dodavatele a na nové informační a komunikační technologie, které budou tento systém podporovat. Na konec je celý návrh zhodnocen a jsou stanoveny jeho předpokládané přínosy a náklady.This thesis deals with selection of appropriate information system for manufactoring and trading company. Firstly analysis of current situation is conducted. This is followed by proposal of requirements completely new information system. There are also described requirements for suppliers and demands for new information and communication technology, which will support this system. Finally there is mentioned appraisal and specified its anticipated benefits and costs.

A stabilization theorem for dynamics of continuous opinions

A stabilization theorem for processes of opinion dynamics is presented. The theorem is applicable to a wide class of models of continuous opinion dynamics based on averaging (like the models of Hegselmann-Krause and Weisbuch-Deffuant). The analysis detects self-confidence as a driving force of stabilization.Comment: 7 pages, no figures, first time presented at First Bonzenfreies Colloquium on Market Dynamics and Quantitative Economics, Sep 9/10 200

Growth in Unemployment Raises Poverty Rates: Most Low-Wage Earnings Constitute Supplement to Primary Household Income

Inequality with respect to personal earned income has increased in recent years. This trend has gone hand in hand with changes in both the employment constellations of households and the labor market activity of individuals (e.g. through 'minijobs'). In particular, the years since 2000 have seen a rise in the share of households with no market income because their members are either registered or hidden unemployed. These findings do not necessarily indicate an increase in relative poverty, because the latter depends on net household income and not just on individual primary incomes. While the risk of poverty also increased in recent years amongst low-wage earners, the rise only applied to those 47% of low-wage earners who live in households without another gainfully employed household member. More than half of all low-wage earners live in households that have a below-average risk of poverty. Unemployment still represents the principal risk factor for poverty. Whereas the likelihood of being poor in the event of unemployment was 29% in 1993, this risk had increased by ten percentage points by 2003. For an unemployed person living alone or whose spouse or partner was not working, the risk of poverty in 2003 was a substantial risk of 53%.

Optimized network structure and routing metric in wireless multihop ad hoc communication

Inspired by the Statistical Physics of complex networks, wireless multihop ad hoc communication networks are considered in abstracted form. Since such engineered networks are able to modify their structure via topology control, we search for optimized network structures, which maximize the end-to-end throughput performance. A modified version of betweenness centrality is introduced and shown to be very relevant for the respective modeling. The calculated optimized network structures lead to a significant increase of the end-to-end throughput. The discussion of the resulting structural properties reveals that it will be almost impossible to construct these optimized topologies in a technologically efficient distributive manner. However, the modified betweenness centrality also allows to propose a new routing metric for the end-to-end communication traffic. This approach leads to an even larger increase of throughput capacity and is easily implementable in a technologically relevant manner.Comment: 25 pages, v2: fixed one small typo in the 'authors' fiel

Lazier Than Lazy Greedy

Is it possible to maximize a monotone submodular function faster than the widely used lazy greedy algorithm (also known as accelerated greedy), both in theory and practice? In this paper, we develop the first linear-time algorithm for maximizing a general monotone submodular function subject to a cardinality constraint. We show that our randomized algorithm, STOCHASTIC-GREEDY, can achieve a $(1-1/e-\varepsilon)$ approximation guarantee, in expectation, to the optimum solution in time linear in the size of the data and independent of the cardinality constraint. We empirically demonstrate the effectiveness of our algorithm on submodular functions arising in data summarization, including training large-scale kernel methods, exemplar-based clustering, and sensor placement. We observe that STOCHASTIC-GREEDY practically achieves the same utility value as lazy greedy but runs much faster. More surprisingly, we observe that in many practical scenarios STOCHASTIC-GREEDY does not evaluate the whole fraction of data points even once and still achieves indistinguishable results compared to lazy greedy.Comment: In Proc. Conference on Artificial Intelligence (AAAI), 201

On exact categories and applications to triangulated adjoints and model structures

We show that Quillen's small object argument works for exact categories under very mild conditions. This has immediate applications to cotorsion pairs and their relation to the existence of certain triangulated adjoint functors and model structures. In particular, the interplay of different exact structures on the category of complexes of quasi-coherent sheaves leads to a streamlined and generalized version of recent results obtained by Estrada, Gillespie, Guil Asensio, Hovey, J{\o}rgensen, Neeman, Murfet, Prest, Trlifaj and possibly others.Comment: 38 pages; version 2: major revision, more explanation added at several places, reference list updated and extended, misprints correcte

Mehr Armut durch steigende Arbeitslosigkeit: Niedriglöhne überwiegend als Zusatzeinkommen im Haushalt

In den letzten Jahren ist die Ungleichheit der individuellen Erwerbseinkommen gestiegen. Dies ging einher mit einer Veränderung der haushaltsspezifischen Erwerbskonstellation und der individuellen Erwerbsbeteiligung (z. B. Minijobs). Insbesondere ist seit 2000 ein steigender Anteil von Haushalten ohne Markteinkommen zu beobachten, weil deren Mitglieder arbeitslos sind oder zur stillen Reserve gehören. Diese Befunde bedeuten nicht zwangsläufig einen Anstieg der relativen Einkommensarmut, denn diese hängt vom Haushaltsnettoeinkommen und nicht allein von den individuellen Primäreinkommen ab. Zwar stieg in den letzten Jahren auch bei der Gruppe der Niedriglohnbezieher das Risiko der Einkommensarmut; dies betraf lediglich jene 47 % der Niedriglohnbezieher in Haushalten ohne einen weiteren Erwerbstätigen. Mehr als die Hälfte aller Niedriglohnbezieher lebt aber in Haushalten mit einem unterdurchschnittlichen Armutsrisiko. Das markanteste Armutsrisiko stellt nach wie vor Arbeitslosigkeit dar. Lag 1993 die Wahrscheinlichkeit, im Falle von Arbeitslosigkeit zur Gruppe der einkommensarmen Personen zu zählen, bei 29 %, war dieses Risiko im Jahre 2003 um 10 Prozentpunkte höher. Lebt ein Arbeitsloser allein im Haushalt oder übt dessen (Ehe-)Partner keine Erwerbstätigkeit aus, betrug das Armutsrisiko im Jahre 2003 sogar 53 %.

A Selection of Research Data Management Tools Throughout the Data Lifecycle

In this document, several useful research data management tools are listed and described for each step of their research throughout the data lifecyle management