bluuebunny/crossref_metadata_2025 huggingface dataset:
Knowledge and Creativity in Digital Society
Authors: Fragnito Riccardo , Annarumma Maria
Published: May 2018

This work deals with the topic of creativity understood as a complex path carried out along all lifetime and that cannot be attributable to the mere accumulation of concepts. The changing social scenario promotes the dimension of the possible, the nonlinearity, the overcoming of preestablished trajectories of knowledge by triggering processes of meta-knowledge and metarepresentation, a dimension in which the creative mind finds a breeding ground.

The work explores the relationship between technology and creativity in consideration of the peculiar segment, the artistic one, where with greater evidence the work of the creative is unfolded.
A system-theory-based model for monthly river runoff forecasting: model calibration and optimization
Authors: Wu Jianhua , Qian Hui , Li Peiyue , Song Yanxun
Published: May 2018

River runoff is not only a crucial part of the global water cycle, but it is also an important source for hydropower and an essential element of water balance. This study presents a system-theory-based model for river runoff forecasting taking the Hailiutu River as a case study. The forecasting model, designed for the Hailiutu watershed, was calibrated and verified by long-term precipitation observation data and groundwater exploitation data from the study area. Additionally, frequency analysis, taken as an optimization technique, was applied to improve prediction accuracy. Following model optimization, the overall relative prediction errors are below 10%. The system-theory-based prediction model is applicable to river runoff forecasting, and following optimization by frequency analysis, the prediction error is acceptable.
The production of present and absent presences in education
Authors: Frelin Anneli , Grannäs Jan
Published: May 2018

Drawing on the distinction between absent and present presences, this article contributes to our understanding of how new managerial and performative discourses are played out in a secondary school context in Sweden. The consequences of numerous educational reforms during the last 20 years include a surge of new independent schools and increased segregation between students due to individual school choice. Following international trends, a yearly national municipal school ranking is published, drawing much attention both in the media and on the policy level, intensifying pressure for results at the municipal level. A case study was conducted in one bottom-ranked Swedish secondary school over the 2012-13 school year, focusing on how relationships between students and staff were negotiated in informal spaces and places. The results illustrate how absent presences and present presences are produced in the practice of schooling. The present presences were publication of results, raising merit scores and grading pressure, and the absent presences were the role of the media in the self-image of schools, increased workload for teachers, the misuse of statistical data and demoralization and determination. The results contribute to the understanding of a) the challenges that teachers and schools are faced with as a consequence of the new managerial and performative discourses in educational settings, and b) the means they draw on to face and resist them in their everyday practices.
Perspectives on English teacher development in rural primary schools in China
Authors: Ping Wang
Published: May 2018

Questionnaires are used to examine Chinese rural primary school English teachers’ needs and challenges and perceptions in the implementation of Standards for Teachers of English in Primary Schools as professional development in rural school contexts in China. A total of 300 teachers participated in the research. Their feedback illustrates that there are serious problems with the current training model and that teachers have a very high expectation of being involved in the Professional Graduate Certificate in Education.
Concept of using the InCaS model to identification, measuring and presenting relational capital of a network enterprises / Koncepcja wykorzystania modelu InCaS do identyfi kacji, pomiaru i prezentowania kapitału relacyjnego w przedsiębiorstwach sieciowych i innych nowoczesnych organizacjach
Authors: Szczepankiewicz Elżbieta
Published: May 2018

Relational capital factors are an important component of the market value of many business entities. For many years attempts have been made at developing uniform methods and models for identification and valuation of relational capital. “Intellectual Capital Statement - Made in Europe” (InCaS) that constitutes a particularly useful, complex tool to assess, to report and to develop the intellectual capital and relational capital of an modern companies. The paper shows application of InCaS project for measuring and presenting relational capital in 25 pilot-SMEs in Europa, in this in 5 pilot-SMEs in Poland. The paper shows also practical application of InCaS concept for assess, to report and to develop the relational capital on the example of a modern company the industry of IT services in Poland - BLOOMING Technologies Sp. z o.o.
Impact of Body Composition, Measured by Computed Tomography Scan, on Acute Pancreatitis Course
Authors: Ozola-Zālīte Imanta , Vīksna Anda , Ivanova Jeļena , Ūdre Agnese , Puķītis Aldis
Published: May 2018

Severe acute pancreatitis occurs in 15–25% of all patients with acute pancreatitis (AP), and has a dismal prognosis. Recognition of severe AP risk factors could provide identification and resuscitation of patients with impending severe course of disease. Our study aim was to analyse body composition, measured by computed tomography (CT) scans, in acute pancreatitis patients and its impact on disease severity. The study was a prospective cohort study carried out in the period from January 2015 – April 2016. In total 100 patients underwent CT imaging. Body constitution was analysed by CT examinations using the ImageJ v1.49q standard software. The third lumbar vertebra was selected as the landmark measurement. Muscular, visceral, subcutaneous, and intramuscular adipose tissue area were measured. Values were normalised for stature to obtain lumbar skeletal muscle and adipose tissue indexes (cm2/m2). Acute pancreatitis severity was determined by Atlanta revised criteria (2012). Among the included patients, moderately severe AP occurred in 83% (83 patients) cases, and severe AP in 17% (17 patients). 38% of the patients had normal weight according to BMI, 33% were overweight 33%, and 28% were obese. Sarcopenia was detected in 51%. Sarcopenia was found in six patients (35%) with severe AP and in 45 patients (54%) with moderately severe AP. General linear model analysis showed that obesity (p value = 0.026) and increased intramuscular fat area (p value = 0.029) had effect on severe AP. In conclusion, body composition analysis showed that adiposity is a risk factor for severe AP, and higher intramuscular fat area seemed to be another risk factor for severe AP.
Phenolics Content in Buckwheat Flour
Authors: Beitāne Ilze , Krūmiņa-Zemture Gita , Krūma Zanda , Cinkmanis Ingmārs
Published: May 2018

The objective of the current study was to analyse the total phenolic concentration (TPC), total flavonoid concentration (TFC), individual phenolic compound concentration and DPPH′ radical scavenging activity of four buckwheat (raw, roasted, white and dark) flour samples obtained from the Latvian market, in comparison to those of wheat flour, which is the most common ingredient in production of cereal products. TPC, TFC, and DPPH′ radical scavenging activity values were determined using spectrophotometric methods. Phenolic compounds were determined based on the high performance liquid chromatographic method (HPLC). All buckwheat flour samples had significantly higher TPC and TFC than wheat flour. The highest TPC (974.74 mg GAE·100 g−1 DW) and TFC (495.31 mg CE·100 g−1 DW) was found in raw buckwheat flour (p < 0.05). Buckwheat flour samples demonstrated similar DPPH′ radical scavenging activity, which ranged from 21.067 to 22.644 mM TE·100 g−1 dry matter, and was significantly higher (p < 0.05) than in wheat flour (0.731 mM TE·100 g−1 of dry matter). Dark buckwheat flour contained the highest level of rutin (4.613 mg·100 g−1), whereas raw buckwheat flour displayed the highest level of 3.5-dihydroxybenzoic acid (6.356 mg·100 g−1), sinapic acid (0.947 mg·100 g−1) and epicatechin (2.608 mg·100 g−1).
Inhibition of Formation of Conjugated Dienes in Linseed Oil
Authors: Kūka Māra , Čakste Ilze , Kūka Pēteris
Published: May 2018

Oxidation of fats and oils reduces the nutritional value of food and causes various health problems. The addition of antioxidants prevents the oxidation of fats in the food. The antioxidant activity of antioxidants represents the ability to inhibit the process of oxidation. The antioxidant activity of herbal extracts has usually been assessed in a linoleic acid emulsion system. The aim of the present study was to evaluate inhibition of conjugated diene formation in Latvian linseed oil. Ethanol extract of the calyx of Hibiscus sabdariffa L., vanillin, α-tocopherol and 2,6-di-tert-butyl-4-methylphenol as additives were compared for their antioxidative activity. The samples of linseed oil with additives were incubated for 24 h at 60 °C and then analysed using UV spectrophotometry (λ = 234 nm). The antioxidant activity of additives was characterised by the percentage of formation of conjugated dienes. The ability of additives to inhibit oxidation in linseed oil decreases as follows: vanillin, 2,6-di-tert-butyl-4-methylphenol and α-tocopherol. Our results indicate that linseed oil can be used to test antioxidative activity of substances.
Bioactive Compounds in Tomatoes at Different Stages of Maturity
Authors: Dūma Māra , Alsiņa Ina , Dubova Laila , Erdberga Ieva
Published: May 2018

Tomato is known as a vegetable with several health benefits due to its high level of bioactive compounds, especially lycopene, phenolics, and vitamin C. The effect of tomato variety and stage of maturity on the bioactive compounds concentration was studied. Ten tomato varieties were grown and collected from a greenhouse at two different stages of ripening. The obtained results showed that there were significant differences in the mean values between analysed parameters according to the stage of ripening and variety. The highest concentration of vitamin C was determined for variety Sakura F1 at maturity stage, and the lowest for variety Sunstreem F1 for unripe fruits. The concentration of phenols and flavonoids increased during tomato ripening and the highest rate was observed for variety Naget F1 (from 7.86 mg·100g−1 to 14.34 mg·100 g−1 (phenols) and flavonoids from 6.09 mg·100 g−1 to 10.03 mg·100 g−1. The concentration of lycopene in the unripe stage was low (mostly about 1 mg·100 g−1) and the most quantitative changes and the highest concentration of lycopene in full maturity stage was determined for variety SV0946TS (27.11 mg·100 g−1) and variety NectarF1 (16.81 mg·100 g−1).
Influence of Steam Treatment and Drying on Carrots Composition and Concentration of Phenolics, Organic Acids and Carotenoids
Authors: Prieciņa Līga , Kārkliņa Daina
Published: May 2018

Carrot (Daucus carota L.) is a globally used vegetable from the Apiacea family. It contains macro and micro elements, as well as various phytochemicals. The aim of the study was to determine concentration of carotenoids and organic acids, phenolic composition and antiradical scavenging activity, and colour changes during steam-blanching (for 1.5 and 3.0 min) and in dried carrots in convective and microwave-vacuum driers. Gravimetric, spectrophotometric, and high performance liquid chromatography (HPLC) methods were used for analysis. Carotenoids in fresh carrots were detected in high amounts, which decreased during thermal treatment and drying. The main organic acids in fresh carrots detected in highest amounts were oxalic, tartaric, quinic, malonic, and citric acids. Ascorbic acid concentration decreased minimally with steam processing, but significantly during drying. Fresh carrots contain minimal amounts of total phenolics, which increased during the thermal and drying processes used, while flavonoid, flavonol, flavan-3-ol and phenolic acid concentration decreased. The compound found in highest amounts by HPLC methods were 3.4-dihydroxybenzoic and 3.5-dihydroxybenzoic acids, catechin, 4-hydroxybenzoic acid, epicatechin and sinapic acid.
Changes in Bone Mineral Density in Young Adults with Type 1 Diabetes Mellitus
Authors: Goia-Socol Monica , Duncea Ileana , Roman Gabriela , Goia-Socol Mihai-Andrei , Leucuţa Daniel-Corneliu , Georgescu Carmen Emanuela
Published: May 2018

Background and aims: Type 1 diabetes mellitus (T1DM) represents a secondary cause of osteoporosis. Our aim was to determine bone mineral density (BMD) changes in a group of young Romanian adults with T1DM and to analyze the factors related to this disease that could have had an impact on bone mass. Material and Methods: Fifty-two young patients with T1DM were compared to 37 healthy volunteers matched for body mass index (BMI). All subjects had their BMD measured at the hip and lumbar spine. Results: We found no statistically significant differences in BMD between T1DM patients and controls (p=0.618 for lumbar spine, p=0.974 for femoral neck and p=0.883 for total hip). Multiple linear regression models detected BMI (p =0.043), smoking (p=0.001) and milk intake (p=0.004 for lumbar spine) as significant BMD determinants. In contrast, no associations were found between BMD and metabolic control, daily insulin dose or presence of diabetic retinopathy and/or neuropathy. Long diabetes duration was negatively associated with BMD in femoral neck (p=0.012). Conclusions: Although we couldn’t find differences between BMD in T1DM patients and controls, the link between diabetes duration and BMD that we found suggests that even young patients with long standing T1DM should have their BMD measured
Analysis of Chronic Kidney Disease – Asociated Glycemic Variability in Patients with Type 2 Diabetes Using Continuous Glucose Monitoring System
Authors: Văduva Cristina , Popa Simona , Moţa Maria , Moţa Eugen
Published: May 2018

Background and Aims. In diabetic patients, chronic kidney disease (CKD) requires special attention due to the multitude of factors that determine glycemic variability. We aimed to assess glycemic variability in patients with CKD and type 2 diabetes mellitus (T2DM) using a continuous glucose monitoring system (CGMS) and identify the predictive value of inter-day and intra-day glycemic variability indices for metabolic imbalance. Material and method. We included 20 diabetic patients (10 CKD patients/10 patients without CKD) and 10 healthy volunteers. Anthropometric parameters, glycated hemoglobin (HbA1c), and glycemic variability indices on CGMS readings were registered. Results. CKD diabetic patients presented significantly higher inter-day and intra-day glycemic variability compared to the diabetic patients without CKD. HbA1c was not significantly different between diabetic subjects with/without CKD. ROC curves indicated that just some CGMS parameters had higher predictive value for metabolic imbalance (HbA1c≥6.5%) but only the percentage of time with glucose values>180 mg/dl (p=0.024) was an independent predictor for HbA1c≥6.5%. Conclusions. Subjects with CKD and T2DM had poor glycemic control and significantly higher glycemic variability comparative to those without CKD, and especially to healthy volunteers. Assessment of glycemic variability indices is more accurate than HbA1c for the quantification of glycemic control in CKD diabetic patients
Neonatal Diabetes – From Gene Discovery yo Clinical Practice Changes
Authors: Guja Cristian , Guja Loreta , Ionescu-Tîrgovişte Constantin
Published: May 2018

Diabetes mellitus is one of the most common chronic diseases but also one of the most heterogeneous. Apart the common phenotypes of type 1 and type 2 diabetes, around 1-2% of all cases arise from a single gene mutation and are known as monogenic diabetes. Diabetes diagnosed within the first 6 months of life is known as neonatal diabetes and has been extensively studied during the last two decades. Unraveling the genetic cause and molecular mechanism of this rare diabetes phenotype led to a dramatic change in the treatment of these children who often can be switched from insulin to sulphonylurea treatment. The aim of this paper is to review the known genetic causes of neonatal diabetes and to highlight the most recent aspects of the disease caused by mutations in the KATP and insulin genes, with a special focus on the individualized treatment of these cases
The Challenges of Corporate Taxation in Iran: The Case of Construction Companies in the Province of Kurdistan
Authors: Gandoman Heidari Shaho , Soldatos Gerasimos
Published: May 2018

The present paper attempts to investigate the challenges of taxation in Iran based on the tax behavior of construction companies in Kurdistan Province. From a 165 questionnaires, Scheffe and Friedman tests were applied to test the following research hypotheses: Efficiency of tax laws, the role of tax experts in filing correct tax reports, the extent to which willing or unwilling tax noncompliance is detectable, and the effectiveness of penalties considering the case of construction companies. The evidence rejects tax law efficiency as well as the efficiency of the penalty-reward system and confirms the negative impact of tax noncompliance on tax revenue. Also, interestingly enough, neither the input of financial expertise in filling out tax reports nor the role of accounting information when taxable income is reported is shown to be statistically significant. Altogether these results point to a highly problematic tax regime in Iran at least in so far as corporate tax from construction companies in Iranian Kurdistan is concerned.
Overcoming Inertia with a Nudge: How the AAIMS Program Increased Advanced Placement Participation in Arkansas
Authors: Holt Andrew , McGarrity Joseph
Published: May 2018

The Arkansas Advanced Initiative for Math and Science (AAIMS) is program with the goal to increase Advanced Placement (AP) participation and increase the passing rate of AP exams. The program offers monetary incentives and support to students and teachers for one year, effectively creating a natural experiment. This paper exploits the one year treatment to empirically show that the program is effective at increasing a school’s AP participation rate by nudging the schools to increase AP offerings and satisfying a latent student demand for AP classes.
A Model to Simulate the Dynamics of Public Debt Sustainability in EU
Authors: Marinescu Ada Cristina , Albu Lucian-Liviu
Published: May 2018

Last decades the public debt increased continuously in all countries of European Union. At present, in many countries this dangerous growth is seriously affecting the general process of economic development. Although in a number of countries the public debt is today larger than 60% of GDP, as the imposed limit by Maastricht Treaty, the problem of its sustainability is varying from country to country. Following old and recent published studies in matter of public debt sustainability, one objective of our study is to analyse the existence of a convergence or a divergence process both at the level of the whole EU and within the two major groups of countries (EU14 – old members of EU, after Brexit, and respectively EU11 – new eastern members adhered to EU after 2000). Other objective is to build a model to simulate the long term dynamics of the public debt as a function of standard variables (such as GDP growth, interest rate, budgetary deficit, etc.). Moreover, by using recent data from Eurostat, IMF, and World Bank, we try to estimate few essential parameters in order to control the public debt sustainability in each country of EU. Finally, countries are grouped in a number of classes for which certain policy measures could be evaluated.
Financial Development and Manufacturing Performance: The Nigerian Case
Authors: Mesagan Ekundayo , Olunkwa Ndubuisi , Yusuf Ismaila
Published: May 2018

The study focused on financial sector development and manufacturing performance in Nigeria over the period of 1981 to 2015. In the study, three indicators such as manufacturing capacity utilization, manufacturing output and manufacturing value added were employed to proxy manufacturing performance while money supply as a percentage of GDP, domestic credit to the private sector and liquidity ratio were employed to proxy financial development. The study observed that credit to the private sector and money supply positively but insignificantly enhanced capacity utilization and output, but negatively impacted value added of the manufacturing sector in the short run. There is slight improvement in the long where both money supply and credit to private sector exert positive impact manufactured output. Hence, it becomes crucial for commercial banks to make available certain percentage of their profits for industrial expansion in order to create linkages between both sectors.
Corporate Sustainability – From a Fuzzy Concept to a Coherent Reality
Authors: Ogrean Claudia , Herciu Mihaela
Published: May 2018

During the last few decades, the search for sustainability has experienced a tremendous momentum, encompassing all the levels of the global system. Fuelled by complex (both proactive and reactive) motivators, the process has surpassed the characteristics of an intellectual endeavor – more preoccupied by idealist goals, and less focused on the actual means to achieve them – and has proved that it can successfully be transposed into the corporate real world – of decision making, objective assessment, and relentless scrutiny. The paper aims to (broadly) explore the world of the most sustainable corporations – based on a descriptive (factual and dynamic) analysis of Corporate Knight’s annual rankings (2016-2018) of the Most Sustainable Corporations – in order to: (a). determine (by comparing and contrasting) the main features these organizations – able to transform the fuzzy concept of corporate sustainability into a coherent reality – display; and (b). set the premises for future (narrower) researches – aiming to explain the “how-s” behind the design, development and implementation of the strategies these corporations follow in their search for (sustainable) competitiveness.
The Erotics of Scenario. On the Construction of the Subject in Postmodern Theatre
Authors: Piroşcă Alin-Daniel
Published: May 2018

Set in the postmodern culture cadres that Lyotard talked about twenty years ago, we are witnessing an accelerated mistrust of a conspicuous value. In fact, all this mistrust has occurred amid a radical overthrow of the way we were accustomed to perceiving the values of modernity. Having its starting point in philosophy, falling into disuse that postmodernity propose grows like a wave that appeared after a stone was thrown into the water. Theatre has not escaped from postmodern articulation, and its subjects have inevitably passed through the postmodern reconfiguration filter. In this article, we will talk about the subject of eroticism, trying to outline our thesis on the idea that the comprehensive synthesis of the receiver in relation to the postmodern performance is based on the construction of the subject folded on the identification of some indicators. Considered as a cultural construct, eroticism is eliminated through its discourse and requires scenarios to be fully understood and recognized. The question inevitably arises: to what extent can we talk about these scenarios in the postmodern performance?
Faces of the Present. Romeo Castellucci’s Postmodernism
Authors: Avram Cristi
Published: May 2018

This article follows the concept of postmodernism through the eyes and work of a contemporary director – Romeo Castellucci. Owing to the fact that this artistic current is constantly developing, trying to define it would be rather useless, although some of its particularities are worth to be mentioned: eclecticism, fragmental, the syncretism of arts, destroying convention, the performance, the installation etc. The above mentioned Italian director is one of the best examples of postmodern directing. Among his great creations, one stands out: the trilogy which develops from Dante Alighieri’s Divine Comedy. By analyzing this production, one may unravel traces of postmodernism.
Synthesis and solubility of brompyromorphite Pb5(PO4)3Br
Authors: Janicka Urszula , Bajda Tomasz , Manecki Maciej
Published: May 2018

The bromide analogue of pyromorphite Pb5(PO4)3Br was synthesized and characterized by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. The solubility of the brompyromorphite was measured at 25°C and pH values of 2.0, 2.6 and 3.2. For the 3 pH measurements, the average solubility product, log KSP, for the reaction Pb5(PO4)3Br ⇔ 5Pb2+ + 3PO- 3- + Br- at 25ºC is -77.38 ± 0.70. The free energy of formation, ΔG°f,298, calculated from this measured solubility product is -3724.7 ± 4.3 kJ mol−1. These results confirm that brompyromorphite is more soluble than pyromorphite.
Preservation of magmatic signals in metavolcanics from Wedel Jarlsberg Land, SW Svalbard
Authors: Gołuchowska Karolina , Barker Abigail K. , Majka Jarosław , Manecki Maciej , Czerny Jerzy , Bazarnik Jakub
Published: May 2018

The purpose of this study is to determine the role of metamorphism and thereby identify the preserved magmatic signature in metavolcanics from Wedel Jarlsberg Land in southwestern Svalbard. Samples have been collected from late Precambrian metavolcanics occurring within metasedimentary rocks of the Sofiebogen Group, as well as dikes cutting older metasedimentary rocks of the Deilegga Group. The volcanic rocks were metamorphosed under greenschist facies conditions during the Caledonian Orogeny. To investigate the role of metamorphism, we present petrography, major and trace element geochemistry, and use factor analysis as a tool to identify correlations that correspond to primary magmatic signals.

The metavolcanics are classified as subalkaline basalt to basaltic andesite and they contain relicts of primary clinopyroxene and plagioclase. The metamorphic minerals are actinolite, secondary plagioclase, chlorite and minerals belonging to the epidote group. Major element variations are highly scattered with no obvious trends observed. The HFSE and REE show strong trends attributed to fractional crystallization. The LILE, Th and La show elevated contents in some samples.

Factor analysis shows that the HFSE and REE are well correlated. The LILE form a separate well correlated group, while the major elements are not correlated, except for Na2O, Fe2O3 and CaO. The lack of correlation for major elements, as well as the lack of observed fractional crystallization trends between these elements suggests that they were modified by metamorphism. The strong correlation of HFSE and REE reflects the original geochemical signal generated by magmatic processes. The correlation of the LILE is consistent with their elevated composition implying the influence of crustal contamination processes, and though some variability is likely superimposed due to metamorphism, the primary magmatic record is not completely destroyed. We conclude that the HFSE and REE are not influenced by metamorphic processes and therefore provide robust records of magmatic processes.
Game control methods in avoidance of ships collisions
Authors: Lisowski Józef
Published: May 2018

The paper introduces application of selected methods of a game theory for automation of
the processes of moving marine objects, the game control processes in marine navigation
and the base mathematical model of game ship control. State equations, control and state
constraints have been defined first and then control goal function in the form of payments
- the integral payment and the final one. Multi-stage positional and multi-step matrix,
non-cooperative and cooperative, game and optimal control algorithms in a collision
situation has been presented. The considerations have been illustrated as an examples of
a computer simulations mspg.12 and msmg.12 algorithms to determine a safe own ship’s trajectory in the
process of passing ships encountered in Kattegat Strait.
Numerical prediction of steady and unsteady tip vortex cavitation on hydrofoils
Authors: Flaszyński Paweł , Szantyr Jan A. , Tesch Krzysztof
Published: May 2018

The article presents the numerical method for prediction of tip vortex cavitation generated on hydrofoils.
This method has been developed in the course of numerical and experimental research described in earlier
publications. The objective of the research was to design the optimum discrete grid structure for this specific
computational task and to select the best turbulence model for such an application The article includes
a short description of the method and a computational example demonstrating its performance. In this
example the results of numerical prediction of the cavitating tip vortex obtained from two commercial CFD
codes are compared with experimental photographs taken in the cavitation tunnel in the corresponding
flow conditions. Altogether nine different flow conditions are tested and analyzed, but only selected results
are included. The accuracy of the numerical predictions is discussed and the reasons for minor existing
discrepancies are identified. The unsteady tip vortex calculations are also presented, showing the fluctuations
of the transverse velocity components predicted for three cross-sections of the cavitating vortex kernel.
The effects of matrix module structure on shipyard panel line’s throughput
Authors: Ozkok Murat
Published: May 2018

Over the last decades a really tough competitive environment has been observed in shipbuilding sector. Under
these circumstances shipyards desire to reduce product cycle time in order to manufacture the product as
soon as possible. For this reason it is required to make some alterations in shipyard production system in
order to reduce cycle time. In this study a panel fabrication line used in a shipyard, has been considered.
The workstations of the panel line have been modeled by using ARENA simulation software and the effects
of matrix module assembly on panel line throughput, have been determined
A study on performance of planing-wing hybrid craft
Authors: Zeraatgar Hamid , Rostami Ali Bakhshandeh , Nazari Abolfazl , Nazari Abolfazl
Published: May 2018

A hybrid craft is defined as a combination of different lifting surfaces. The lift force can be of aerodynamic
or hydrodynamic character. This research deals with the conditions of using planing mono-hulls equipped
with a couple of wings, called planing-wing hybrid craft. A parametric study is conducted by using Vortex
Lattice Method to determine feasibility of using an aerodynamic wing mounted to planing craft. It has
been determined that the wing area should be more than twice as much as the wetted surface of the craft,
to get an effective wing for planing craft. Furthermore, the wing should be so designed as to obtain its
high aspect ratio. Maximum lift force contribution resulting from different wing configurations considered
in this study is less than 35 percent of the total hydrodynamic lift force at an arbitrary condition. On this
basis it may be concluded that the wing may be effectively used only in special conditions, hence this is
not recommended for general application.
Investigations on corrosion of aircrafts in the aspect of prolonged service life and operation driven by their technical condition
Authors: Barszcz Piotr
Published: May 2018

Research studies that are conducted by both the Air Force Institute of Technology (AFIT)
and other domestic and foreign organizations indicate that investigations of corrosion phenomena
present a very important factor with respect to prolongation of technical resources
and operation of aircraft driven by their actual technical condition. The investigation of the
corrosion degree and deterioration of protective coatings must be carried out in a systemic
manner with thorough analysis of information that bring together the aircraft operation and
the processes of corrosion and deterioration of protective coatings. The investigation must
comprise measurements of the atmospheric corrosion in order to determine corrosive
aggressiveness of the atmosphere and establish frequency and scope of corrosion inspection.
Only the analysis of gathered information with its characteristics may guarantee safe
operation of structural components of aircrafts according to their actual technical condition.
This paper outlines the approach to corrosion investigation that is in place in AFIT.
Automating the creation of channel cross section data from aerial laser scanning and hydrological surveying for modeling flood events / Automatická tvorba geometrie vodních toků na základě syntézy dat z leteckého laserového skenování a hydrologického měření pro modelování povodňových událostí. j. hydrol., hydromech., 60, 2012, 4; 25 lit., 8 obr., 5 tab.
Authors: Roub Radek , Hejduk Tomáš , Novák Pavel
Published: May 2018

Knowing the extent of inundation areas for individual N-year flood events, the specific flood scenarios, and having an idea about the depths and velocities in the longitudinal or transverse water course profile provided by hydrodynamic models is of key importance for protecting peoples’ lives and mitigating damage to property. Input data for creating the watercourse computational geometry are crucial for hydrodynamic models. Requirements for input data vary with respect to the hydrodynamic model used. One-dimensional (1D) hydrodynamic models in which the computing track is formed by cross-sectional profiles of the channel are characterized by lower requirements for input data. In two-dimensional (2D) hydrodynamic models, a digital terrain model is needed for the entire area studied. Financial requirements of the project increase with regard to the input data and the model used. The increase is mainly due to the high cost of the geodetic surveying of the stream channel. The paper aims at a verification and presentation of the suitability of using hydrological measurements in developing a schematization (geometry) of water courses based on topographic data gained from aerial laser scanning provided by the Czech Office for Surveying, Mapping and Cadastre. Taking into account the hydrological measurement during the schematization of the water course into the hydrodynamic model consists in the derivation of flow rate achieved at the time of data acquisition using the method of aerial laser scanning by means of hydrological analogy and in using the established flow rate values as a basis for deepening of the digital terrain model from aerial laser scanning data. Thus, the given principle helps to capture precisely the remaining part of the channel profile which is not reflected in the digital terrain model prepared by the method of aerial laser scanning and fully correct geometry is achieved for the hydrodynamic model.
Influence of model structure on base flow estimation using Bilan, frier and HBV-light models / Vplyv štruktúry modelu na stanovenie veľkosti podzemného odtoku využitím modelov bilan, frier a hbv-light. j. hydrol. hydromech., 60, 2012, 4; 29 lit., 7 obr., 1 tab.
Authors: Machlica Andrej , Horvát Oliver , Horáček Stanislav , Oosterwijk Jacob , Van Loon Anne F. , Fendeková Miriam , Van Lanen Henny A. J.
Published: May 2018

Hydrological models are widely used tools to solve a broad range of hydrological issues. Each model has its own structure defining inter-relationships of hydrological balance components, and comparative differences in the models’ inner structure must be taken into account when discrepancies result from the same data. Results of base flow simulation by three different models BILAN, FRIER and HBV-light were compared based on knowledge of the models’ internal structure. It was proven that the courses of modelled parameters are quite similar, but that the respective values differ. The highest base flow values were simulated by the BILAN model, due to the threshold value of the soil moisture storage incorporated within this model’s structure. The lowest values were obtained by HBV-light model. Simulated base flow values were compared with groundwater heads and minimum monthly discharges. This comparison showed that the base flow values in the Nitra catchment at Nedožery profile simulated by BILAN and FRIER models are closer to the reality than those, simulated by HBV-light model.
Isotopes of oxygen-18 and deuterium in precipitation in Slovakia / Izotopy kyslíka-18 A deutéria v zrážkach na Slovensku
Authors: Holko Ladislav , Dóša Michal , Michalko Juraj , Šanda Martin
Published: May 2018

The article synthesizes available information on isotopic composition of precipitation in Slovakia (the Western Carpathians). Monthly δ18O data from eleven stations and period 1988-1997 were used to investigate correlations among the stations, altitude, air temperature and precipitation amount effects. The mean annual altitude and air temperature gradients of δ18O in precipitation were 0.21‰/100 m and 0.36‰/1°C, respectively. Maps of spatial distribution of mean annual δ18O in precipitation based on both gradients were constructed. The two maps do not significantly differ for the majority of Slovakia. δ2H data were available for only three stations. Local meteoric water line derived for the station with the longest data series (δ2H = = 7.86δ18O + 6.99) was close to the Global Meteoric Water line. Its parameters in periods 1991-1993 and 1991-2008 did not change. The study indicates that a more detailed monitoring of isotopic composition of precipitation in mountains should be carried out in the future. The highest station exhibited very small seasonal variability of δ18O in precipitation compared to other Slovak stations. The second highest mountain station had significantly higher deuterium excess than the neighboring stations located in the valley. In some analyses the data from the nearest stations situated abroad (Vienna, Krakow) were used.
Basset force in numerical models of saltation / Bassetova síla v numerických modelech saltace částic
Authors: Lukerchenko Nikolay , Dolansky Jindrich , Vlasak Pavel
Published: May 2018

In numerical models of fluid flow with particles moving close to solid boundaries, the Basset force is usually calculated for the particle motion between particle-boundary collisions. The present study shows that the history force must also be taken into account regarding particle collisions with boundaries or with other particles. For saltation - the main mode of bed load transport - it is shown using calculations that two parts of the history force due to both particle motion in the fluid and to particle-bed collisions are comparable and substantially compensate one another. The calculations and comparison of the Basset force with other forces acting on a sand particle saltating in water flow are carried out for the different values of the transport stage. The conditions under which the Basset force can be neglected in numerical models of saltation are studied.
River sediment transport and coastal erosion in the southeastern Black Sea rivers / Transport riečnych sedimentov a erózia pobrežia riek krajiny v juhovýchodnej časti čierneho mora
Authors: Berkun Mehmet , Aras Egemen
Published: May 2018

In the Southeastern Black Sea Region, rivers are dammed for hydroelectric power and irrigation. The natural course of fluvial alluvium transport is almost completely altered because of planned and constructed dams and coastal protection measures. Decreasing volume of sediment carried to the sea cause intensification of the shore erosion. The Black Sea Rivers and coastal areas of Turkey and Georgia are under heavy anthropogenic pressure because of the bed material extraction and coastal erosion rate. In this study, environmental effects of dams and related effects of sediment transport on coastal erosion in the Eastern Black Sea region are discussed.
Plants and biological soil crust influence the hydrophysical parameters and water flow in an aeolian sandy soil / Vplyv rastlín a biologického pôdneho pokryvu na hydrofyzikálne parametre a prúdenie vody v piesočnatej pôde
Authors: Lichner Ľubomír , Holko Ladislav , Zhukova Natalia , Schacht Karsten , Rajkai Kálmán , Fodor Nándor , Sándor Renáta
Published: May 2018

This study tested the hypothesis that the changes in hydrophysical parameters and heterogeneity of water flow in an aeolian sandy soil have the same trend as the process of succession. Three sub-sites were demarcated at the area of about 50 m x 50 m. The first sub-site was located at the pine-forest glade covered with a biological soil crust and represented the initial stage of succession. The second sub-site was located at the grassland and represented more advanced stage of succession. The third sub-site was located at the pine forest with 30-year old Scots pines and represented advanced stage (close to climax) of succession. The sandy soil at the surface was compared to the soil at the pine-forest glade at 50 cm depth, which served as a control because it had a similar texture but limited impact of vegetation or organic matter. It was found that any type of vegetation cover studied had a strong influence on hydrophysical parameters and heterogeneity of water flow in an aeolian sandy soil during hot and dry spells. The changes in some hydrophysical parameters (WDPT, R, k(-2 cm), Sw(-2 cm), ECS and DPF) and heterogeneity of water flow in an aeolian sandy soil had the same trend as the process of succession, but it was not so in the case of Ksand Se(-2 cm), probably due to the higher content of smaller soil particles in grassland soil in comparison with that content at other sub-sites. Both the persistence and index of water repellency of pure sand differed significantly from those of grassland, glade and forest soils. The highest repellency parameter values in forest soil resulted in the lowest value of both the water sorptivity and hydraulic conductivity in this soil in comparison with other soils studied. The highest value of ethanol sorptivity and the lowest value of saturated hydraulic conductivity in the grassland soil in comparison with other soils studied were due to the higher content of fine-grained (silt and clay) particles in the grassland soil. The effective cross section and the degree of preferential flow of pure sand differed significantly from those of grassland, glade and forest soils. The change in soil hydrophysical parameters due to soil water repellency resulted in preferential flow in the grassland, glade and forest soils, while the wetting front in pure sand area exhibited a form typical of that for stable flow. The latter shape of the wetting front can be expected in the studied soils in spring, when soil water repellency is alleviated substantially. The columnar shape of the wetting front, which can be met during heavy rains following long dry and hot spells, was attributed to redistribution of applied water on the surface to a series of micro-catchments, which acted as runon and runoff zones.
Creative-Based Strategies in Small and Medium-Sized Cities: Key Dimensions of Analysis
Authors: Selada Catarina , Vilhena Da Cunha Inês , Tomaz Elisabete
Published: May 2018

The present article intends to contribute to the literature and research agenda regarding the importance of the creative economy as a driver for the revitalisation and development of small and medium-sized cities in Europe. Several studies argue that these territorial areas are necessarily doomed to failure and decline due to the lack of critical mass and density in terms of economic and institutional resources. However, some small towns are changing their development path towards a new ‘urban’ paradigm. The present research aims to identify and analyse a set of dimensions that have to be taken into consideration in the implementation of creative-based strategies in small and medium-sized cities, namely: governance factors, endogenous factors, and territorial embeddedness.
Isotopy of latin squares in cryptography
Authors: Grošek Otokar , Sýs Marek
Published: May 2018

We present a new algorithm for a decision problem if two Latin squares are isotopic. Our modification has the same complexity as Miller’s algorithm, but in many practical situations is much faster. Based on our results we study also a zero-knowledge protocol suggested in [3]. From our results it follows that there are some problems in practical application of this protocol.
Dead-Beat and reaching law based sliding mode control laws for perishable inventories with transportation losses
Authors: Bartoszewicz Andrzej , Maciejewski Michał
Published: May 2018

This paper describes discrete sliding mode (SM) supply management strategies for inventory systems with perishable goods and transportation losses. In the considered systems, the stock used to satisfy the unknown, bounded and time-varying demand is replenished with some delay from a distant supply source. The on-hand stock deterioration during lead-time delay, as well as commodity losses in supply process are explicitly taken into account. Two supply management strategies are proposed. The first one ensures fast reaction to the imposed demand variations, but may result in excessive control signal magnitude at the beginning of the inventory management process. Therefore, in order to conform to supplier limitations we also develop an alternative control strategy based on the concept of the reaching law. That strategy helps reduce the initial supply rate and satisfy the supplier limitations. A number of desirable properties of both proposed strategies are formulated and formally proved. These properties include full customer demand satisfaction and elimination of the risk of exceeding the warehouse capacity.
Backstepping sliding mode controller improved with fuzzy logic: Application to the quadrotor helicopter
Authors: Zeghlache Samir , Saigaa Djamel , Kara Kamel , Harrag Abdelghani , Bouguerra Abderrahmen
Published: May 2018

In this paper we present a new design method for the fight control of an autonomous quadrotor helicopter based on fuzzy sliding mode control using backstepping approach. Due to the underactuated property of the quadrotor helicopter, the controller can move three positions (x;y; z) of the helicopter and the yaw angle to their desired values and stabilize the pitch and roll angles. A first-order nonlinear sliding surface is obtained using the backstepping technique, on which the developed sliding mode controller is based. Mathematical development for the stability and convergence of the system is presented. The main purpose is to eliminate the chattering phenomenon. Thus we have used a fuzzy logic control to generate the hitting control signal. The performances of the nonlinear control method are evaluated by simulation and the results demonstrate the effectiveness of the proposed control strategy for the quadrotor helicopter in vertical flights.
Topology optimization of trusses using bars exchange method
Authors: Bojczuk D. , Rębosz-Kurdek A.
Published: May 2018

The algorithm of optimization of trusses is presented in the paper, where for topology optimization the bars exchange method is used. In the first case, the problem aimed at cost minimization with a constraint set on global stiffness is formulated. In the second case, the problem of minimizing the cost function subjected to stress and cross-sectional area constraints is discussed and here the multiple-load case is taken into consideration. The conditions for introduction of topology modification and its acceptance are specified. The paper is illustrated with three examples.