Input Shaping of the Synchronous Generator for Reduction of Self‐induced Oscillations

This article suggests the application of input shaping for the elimination of electromechanical oscillations arising from changes in the operating point of the synchronous generator. Poorly damped poles are the cause of electromechanical oscillations of the synchronous generator. Various power system stabilizers (PSS) are now used to reduce the electromechanical oscillations. Input shaping is a feedforward control and therefore does not require the measurement of electrical and mechanical quantities of the synchronous generator unlike the PSS. It is possible to apply the input shaping for the excitation system of synchronous generators with or without PSS.     

Applying business context to calculate subsets of business document standards

Business documents directly exchanged between applications usually follow a certain business document standard. No matter whether these standards are traditional EDI standards or XML-based, they are very generic including all elements that may be of need to any company in this world. Before being used in a partnership, a subset of these elements has to be defined based on the business context (geopolitical region, industry, etc.). Usually the definition of these subsets—called Message Implementation Guidelines—starts from scratch, and, thus, is very time-consuming. In this paper we present an approach to explicitly assign context to the definition of Message Implementation Guidelines. This contextual information is also used to calculate a subset for to-be-developed Message Implementation Guidelines based on existing ones. The corresponding approach is supported by a prototype implementation.     

Changes in the composition and sensory properties of Croatian cheese in a lamb skin sack (Sir iz mišine) during ripening

Croatian traditional cheese, which ripens in a lamb skin sack, was studied to determine compositional, biochemical and sensory changes over 60 days of ripening. The ripening time had a significant effect on the chemical, biochemical and sensory parameters, particularly on the medium‐ and long‐chain free fatty acids (P < 0.05) and total FFAs (P < 0.001). At the end of ripening palmitic, oleic and stearic acids were the predominant FFAs. Cheese ripened for more than 45 days was less acceptable to consumers as a consequence of extensive proteolysis and lipolysis. Therefore, ripening for more than 45 days, which is commonly practised by cheesemakers, is not recommended.     

Dual Escherichia coli DNA Gyrase A and B Inhibitors with Antibacterial Activity

The emergence of multidrug-resistant bacteria is a global health threat necessitating the discovery of new antibacterials and novel strategies for fighting bacterial infections. We report first-in-class DNA gyrase B (GyrB) inhibitor/ciprofloxacin hybrids that display antibacterial activity against Escherichia coli. Whereas DNA gyrase ATPase inhibition experiments, DNA gyrase supercoiling assays, and in vitro antibacterial assays suggest binding of the hybrids to the E. coli GyrA and GyrB subunits, an interaction with the GyrA fluoroquinolone-binding site seems to be solely responsible for their antibacterial activity. Our results provide a foundation for a new concept of facilitating entry of nonpermeating GyrB inhibitors into bacteria by conjugation with ciprofloxacin, a highly permeable GyrA inhibitor. A hybrid molecule containing GyrA and GyrB inhibitor parts entering the bacterial cell would then elicit a strong antibacterial effect by inhibition of both the GyrA and GyrB subunits of DNA gyrase and potentially slow bacterial resistance development.     

Automated construction activity monitoring system

Building activities are inadequately monitored during construction projects when attempting to satisfy the need for information, especially in those cases of unforeseen events and conditions on-site. Many IT-supported methods have been introduced, but so far none has been able to deliver satisfactory and reliable information. This paper presents a combined method, consisting of three components: an automated activity tracking subsystem based on image recognition, an automated material tracking subsystem, and a mobile computing supported communication environment. All subsystems are based on the same 4D model of a building.     

Integrating resource production and construction using BIM

This paper presents the outcomes of a research and development project carried out at the University of Maribor, Construction IT Centre, with regard to the introduction of a building information model (BIM) and a model based construction process into the operational environment of a construction company. The initiative for the project came from the industry and was performed as a joined effort of the research organization and the construction company. Work was performed in the scope of an industrialized construction environment, with the main aim to integrate mass production prefabrication processes with construction site activities. BIM was used as a link between an enterprise resource planning (ERP) information system that supports manufacturing process and construction object related information, mainly handled by CAD tools. The benefits of this link are presented with regard to project progress monitoring and material flow management.     

New Primary Dew-Point Generators at HMI/FSB-LPM in the Range from ?70?°C to +60?°C

To extend the dew-point range and to improve the uncertainties of the humidity scale realization at HMI/FSB-LPM, new primary low- and high-range dew-point generators were developed and implemented in cooperation with MIKES, in 2009 through EUROMET Project No. 912. The low-range saturator is designed for primary realization of the dew-point temperature scale from ?70?°C to +?5?°C, while the high-range saturator covers the range from 1?°C to 60?°C. The system is designed as a single-pressure, single-pass dew-point generator. MIKES designed and constructed both the saturators to be implemented in dew-point calibration systems at LPM. The LPM took care of purchasing and adapting liquid baths, of implementing the temperature and pressure measurement equipment appropriate for use in the systems, and development of gas preparation and flow control systems as well as of the computer-based automated data acquisition. The principle and the design of the generator are described in detail and schematically depicted. The tests were performed at MIKES to investigate how close both the saturators are to an ideal saturator. Results of the tests show that both the saturators are efficient enough for a primary realization of the dew-point temperature scale from ?70?°C to +?60?°C, in the specified flow-rate ranges. The estimated standard uncertainties due to the non-ideal saturation efficiency are between 0.02?°C and 0.05?°C.     

Multivariate online kernel density estimation with Gaussian kernels

We propose a novel approach to online estimation of probability density functions, which is based on kernel density estimation (KDE). The method maintains and updates a non-parametric model of the observed data, from which the KDE can be calculated. We propose an online bandwidth estimation approach and a compression/revitalization scheme which maintains the KDE's complexity low. We compare the proposed online KDE to the state-of-the-art approaches on examples of estimating stationary and non-stationary distributions, and on examples of classification. The results show that the online KDE outperforms or achieves a comparable performance to the state-of-the-art and produces models with a significantly lower complexity while allowing online adaptation.     

Chemical Ecology of Cave-Dwelling Millipedes: Defensive Secretions of the Typhloiulini (Diplopoda,Julida, Julidae)

Cave animals live under highly constant ecological conditions and in permanent darkness, and many evolutionary adaptations of cave-dwellers have been triggered by their specific environment. A similar “cave effect” leading to pronounced chemical interactions under such conditions may be assumed, but the chemoecology of troglobionts is mostly unknown. We investigated the defensive chemistry of a largely cave-dwelling julid group, the controversial tribe “Typhloiulini”, and we included some cave-dwelling and some endogean representatives. While chemical defense in juliform diplopods is known to be highly uniform, and mainly based on methyl- and methoxy-substituted benzoquinones, the defensive secretions of typhloiulines contained ethyl-benzoquinones and related compounds. Interestingly, ethyl-benzoquinones were found in some, but not all cave-dwelling typhloiulines, and some non-cave dwellers also contained these compounds. On the other hand, ethyl-benzoquinones were not detected in troglobiont nor in endogean typhloiuline outgroups. In order to explain the taxonomic pattern of ethyl-benzoquinone occurrence, and to unravel whether a cave-effect triggered ethyl-benzoquinone evolution, we classed the “Typhloiulini” investigated here within a phylogenetic framework of julid taxa, and traced the evolutionary history of ethyl-benzoquinones in typhloiulines in relation to cave-dwelling. The results indicated a cave-independent evolution of ethyl-substituted benzoquinones, indicating the absence of a “cave effect” on the secretions of troglobiont Typhloiulini. Ethyl-benzoquinones probably evolved early in an epi- or endogean ancestor of a clade including several, but not all Typhloiulus (basically comprising a taxonomic entity known as “Typhloiulus sensu stricto”) and Serboiulus. Ethyl-benzoquinones are proposed as novel and valuable chemical characters for julid systematics.     

Intercomparison of the Dew-Point Temperature Realizations at LPM and MIKES in the Range from ?70?°C to +?20?° C

The first European humidity key comparison EURAMET-T.K6 was completed in 2008, and it covered the dew-point temperature range from ?50?°C to +?20?°C. Both LPM and MIKES participated in the comparison, but a new low dew-point generator was introduced at LPM as a result of progress in the EUROMET P912 project. To extend the range of available comparison evidence down to ?70?°C and to study the validity of improved uncertainties of LPM, a bilateral comparison was carried out between LPM and MIKES in 2009?C2010. The applied comparison procedure was similar to that applied in EURAMET-T.K6. However, only one transfer standard was used instead of two units and the measurement point ?70?°C was added in the measurement scheme. The results show that the bilateral equivalence between LPM and MIKES is between (0.00 ± 0.06)?°C and (0.02 ± 0.08)?°C in the range from ?50?°C to +?20?°C and (0.01 ± 0.10)?°C at ?70?°C. Using MIKES results as the link to the EURAMET.T-K6, it is shown that the difference between the results obtained with the new LPM dew-point temperature standard and the EURAMET Comparison Reference Values is between (?0.02 ± 0.08)?°C at 20?°C and (+?0.02 ± 0.07)?° C at ?50?°C.