Polynomial-time data reduction is a classical approach to hard graph problems. Typically, particular small subgraphs are replaced
by smaller gadgets. We generalize this approach to handle any small subgraph that has a small separator connecting it to the
rest of the graph. The problem we study is the NP-hard Balanced Subgraph problem, which asks for a 2-coloring of a graph that minimizes the inconsistencies with given edge labels. It has applications
in social networks, systems biology, and integrated circuit design. The data reduction scheme unifies and generalizes a number
of previously known data reductions, and can be applied to a large number of graph problems where a coloring or a subset of
the vertices is sought. To solve the instances that remain after reduction, we use a fixed-parameter algorithm based on iterative
compression with a very effective heuristic speedup. Our implementation can solve biological real-world instances exactly
for which previously only approximations were known. In addition, we present experimental results for financial networks and
random networks. 相似文献
Two individuals who sustained traumatic brain injuries from motorcycle accidents were taught several verbal responses by using tact, mand, and intraverbal training procedures. The rate of acquisition for each operant and the transfer to untrained verbal operants involving the same response topography were measured. The results showed that tacts and intraverbals were acquired quickest, and training on the tact produced the greatest amount of transfer to the untrained verbal operants. Intraverbal training also resulted in transfer for both subjects, but to varying degrees. Direct mand training proved to be the least efficient way to generate a mand repertoire, and when acquired showed least amount of transfer to the untrained operants. These results seem to be in contrast with the findings of similar research with developmentally disabled individuals, and may have implications for methods of language instruction for the brain injured population.
Breeding bird communities in Berlin were investigated at five study sites, which represent an structural urban-rural gradient,
from densely built-up areas with sealed ground to green areas such as large parks. In this paper, we tested the Hasse Diagram
Technique (HDT), an approach belonging to partial order theory, for its appropriateness to extract information about changes
in species composition from our data set. As expected, the overall number of bird species was positively correlated with the
urban-rural gradient, increasing from 12 found in the city center to 28 in an urban park. By HDT analysis, four different
sub-groups of birds could be identified, contributing differentially to the increase in species number: (1) ubiquists, i.e.,
species found at each study site, (2) a sub-group, the species’ number of which was positively correlated with the urban-rural
gradient, increasing with increasingly green areas, (3) a sub-group, the species’ number of which was negatively correlated
with the urban-rural gradient, decreasing with a declining density of buildings, and (4) species, the distribution of which
did not show any correlation with the urban-rural gradient. The results show that HDT is a suitable tool for formalized analysis
of the pattern of species’ communities along an environmental gradient. 相似文献
The author demonstrates basing on a case study, that the development of a consultation system is a process that requires time and patience of everyone involved. Not a fast decided definition of a consultation method with the corresponding setting is the first step but a clarification of the request. That is what the author is pleading for a phase of detailed analysis with the potential client. 相似文献
Incorporation of the behavioral issues of the decision maker (DM) is among the aspects that each Multicriteria Decision Making
(MCDM) method implicitly or explicitly takes into account. As postulated by regret theory, the feelings of regret and rejoice
are among the behavioral issues associated with the entire decision making process. Within the context of MCDM, the DM may
feel regret, when the chosen alternative is compared with another one having at least one better criterion value. PROMETHEE
II is a widely known MCDM method that makes no explicit incorporation of regret attitude of the DM. In this paper, we elaborate
on the applicability of regret theory to MCDM context. In particular, we investigate the findings of regret theory and explore
the parallel between regret theory and PROMETHEE II method. Relying on the concepts of regret theory, we demonstrate how a
decision that is made using a PROMETHEE II based outranking method conforms to the regret attitude of the DM. 相似文献
The term “information” has become a universal and omnipresent keyword in almost all areas of our modern world—be it in science or society in general. This is not only obvious from the naming of whole scientific branches like Information Theory, Information Science or Informatics but even more from common speaking—characterising our present time and society as information age viz. information society. However, what “information” might mean, is by no means clear and there is a wide range of interpretations covering, among others, its technical, communicational, educational, mental, and scientific aspects. But is the use of the same term justified when adopted in Biology, Physics, Archaeology, Law, Communication Technology, and Informatics (to list just a few of the involved scientific branches) or do its different uses at least have some common characteristics—some sort of common denominator? Is information natural, e.g. manifesting itself as a material phenomenon residing in organisms, stars, atoms, or genes, or is it just a cultural product of human communication, thinking, and interpretation? In this article, we try to clarify some of the most important interpretations, discuss and contrast them with the Informatics point of view. Interpretations range from taking information as material, transferable signals (following Shannon’s Information Theory or the genetic approaches), treating it as a sign (following a semiotic approach), as a commercial product (now common in Web-based Information Business) to considering it a pure mental phenomenon bound to humans or human-like individuals or even to groups and societies. Based on these interpretations, we shall throw a critical glance on current trends in human science and society—focusing on the now popular concept of “information society”—and then derive some theses and guidelines for further research escorting the growth and dispersal of information technology. As it will turn out, an information society which defines itself through the number of computers, internet connections and network links is based on a very narrow, techno-centric concept of information. However, a reflection on the educational and cultural aspects of information might lead to a better-qualified society consisting of responsible and critical citizens. 相似文献