Ordering Metro Lines by Block Crossings

A problem that arises in drawings of transportation networks is to minimize the number of crossings between different transportation lines. While this can be done efficiently under specific constraints, not all solutions are visually equivalent. We suggest merging crossings into block crossings, that is, crossings of two neighboring groups of consecutive lines. Unfortunately, minimizing the total number of block crossings is NP-hard even for very simple graphs. We give approximation algorithms for special classes of graphs and an asymptotically worst-case optimal algorithm for block crossings on general graphs. That is, we bound the number of block crossings that our algorithm needs and construct worst-case instances on which the number of block crossings that is necessary in any solution is asymptotically the same as our bound

Awakening the Law of Contraband in the Russia-Ukraine Conflict

Following the collapse of the Black Sea Grain Initiative, both Russia and Ukraine announced measures against shipping that may have introduced counter-contraband operations into the maritime dimension of the Russia-Ukraine conflict. The law of contraband, which is at the heart of the law of naval warfare, regulates such operations. The law of contraband has, however, not been often used in current conflicts and some of its details are not crystalized as generally accepted law. Awakening this instrument in the current conflict brings questions for both belligerents and non-State parties, some of whom have adopted a position of qualified neutrality that allows them to militarily support Ukraine. This article revisits the law of contraband in the context of the current conflict and discusses the intersection between the law of contraband and the concept of qualified neutrality

Electron Energy-Loss Spectroscopy: A versatile tool for the investigations of plasmonic excitations

The inelastic scattering of electrons is one route to study the vibrational and electronic properties of materials. Such experiments, also called electron energy-loss spectroscopy, are particularly useful for the investigation of the collective excitations in metals, the charge carrier plasmons. These plasmons are characterized by a specific dispersion (energy-momentum relationship), which contains information on the sometimes complex nature of the conduction electrons in topical materials. In this review we highlight the improvements of the electron energy-loss spectrometer in the last years, summarize current possibilities with this technique, and give examples where the investigation of the plasmon dispersion allows insight into the interplay of the conduction electrons with other degrees of freedom

Improving the Quality of Disabled People’ Life at Work Via ISO, 9001 Standard

AbstractThe quality of life is influenced by many elements. One of them is employment. People with disabilities have a lot of problems at work (if they are so lucky to get one) – starting with adaptation to a workplace and team, through difficulties during the working process or communication between them and the employer. The aim of this paper is to introduce ISO, 9001 standard as a suitable element that positively influence the quality of life of disabled people.This paper represents one of the outputs of sub activity of the project called The Research on Quality of Life of People with Special Needs (IGA_PdF_2013_006), which was realised by Students grants contest of Palacký University in Olomouc

Many-to-One Boundary Labeling with Backbones

In this paper we study \emph{many-to-one boundary labeling with backbone leaders}. In this new many-to-one model, a horizontal backbone reaches out of each label into the feature-enclosing rectangle. Feature points that need to be connected to this label are linked via vertical line segments to the backbone. We present dynamic programming algorithms for label number and total leader length minimization of crossing-free backbone labelings. When crossings are allowed, we aim to obtain solutions with the minimum number of crossings. This can be achieved efficiently in the case of fixed label order, however, in the case of flexible label order we show that minimizing the number of leader crossings is NP-hard.Comment: 23 pages, 10 figures, this is the full version of a paper that is about to appear in GD'1

Aspects to Be Considered when Implementing Technology Enhanced Learning Approaches. A Literature Review

The significance of approaches to technology-enhanced learning (TEL) has increased rapidly during the last few years. Nowadays in education different approaches such as game-based learning, web-based learning, video-based online courses, and many others are used on a daily basis. However, what defines the success of technology-enhanced learning approaches and how can such approaches be developed in a structured way? Furthermore, what different aspects have to be considered while doing so? To answer these questions, 4567 publications were analyzed in this present literature review in order to recognize the different aspects of implementing technology-enhanced learning approaches. Finally, 20 categories are defined in four main areas that summarize all the aspects in the field of technology-enhanced learning. Moreover, the study also reveals research areas that are important but hardly investigated in the observed journals of this study

Interference and facilitation effects of semantic and phonological contextual priming: A treatment case study

We report a case study of a treatment for naming using contextual production priming, a technique that combines massed repetition priming and naming with context defined by the linguistic relationship among words being trained. Our participant, 402, presented with primarily a phonological impairment, but semantic deficits were also present. Both semantic and phonological training contexts resulted in interference during training but only the semantic context facilitated learning. Additionally, each context influenced the prevalence of error type in that context (fewer semantic errors in the phonological context and fewer semantic errors in the phonological context). Implications of these findings are discussed

Plasmons and Interband Transitions of Ca11_{11}Sr3_3Cu24_{24}O41_{41} investigated by Electron Energy-Loss Spectroscopy

Electron energy-loss spectroscopy studies have been performed in order to get a deeper insight into the electronic structure and elementary excitations of the two-leg ladder system Ca$_{11}$Sr$_3$Cu$_{24}$O$_{41}$. We find a strong anisotropy of the loss function for momentum transfers along the a and c-crystallographic axis, and a remarkable linear plasmon dispersion for a momentum transfer parallel to the legs of the ladders. The investigated spectral features are attributed to localized and delocalized charge-transfer excitations and the charge carrier plasmon. The charge carrier plasmon position and dispersion in the long wave-length limit agree well with expectations based upon the band structure of the two-leg ladder, while the observed quasi-linear plasmon dispersion might be related to the peculiar properties of underdoped cuprates in general.Comment: 16 pages, 8 figure