bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Site-Specific Wind Field Parameters and Their Effect on Loads of Offshore Wind Turbines
Authors: Ernst Benedikt , Seume Jörg R.
Published: October 2012

The main contributing factors to unsteady loading of Offshore Wind Turbines (OWT) are wind shear, turbulence, and waves. In the present paper, the turbulence intensity and the wind shear exponent are investigated. Using data from the FINO 1 research platform, these parameters are analyzed and compared with the proposed wind field parameters in the IEC standard 61400-3. Based on this analysis, aeroelastic simulations are performed to determine the effect of wind field parameters on the fatigue and the extreme loads on the rotor blades. For the investigations, the aeroelastic model of a 5 MW OWT is used with a focus on design load cases in an operating state (power production). The fatigue loads are examined by means of the damage-equivalent load-range approach. In order to determine the extreme loads with a recurrence period of 50 years, a peak over threshold extrapolation method and a novel method based on average conditional exceedance rates are used. The results show that the requirements of the IEC standard are very conservative for the design of the rotor blades. Therefore, there could be a large optimization potential for the reduction of weight and cost of the rotor blades.
Plant Invasions: Symptoms and Contributors Rather Than Causes of Environmental Degradation
Authors: Jurskis Vic
Published: October 2012

Native or exotic woody plants can proliferate in dry and moist eucalypt ecosystems shading out many other native species, contributing to chronic decline of eucalypts and reinforcing unnatural fire regimes and nutrient cycling processes. Whether native or exotic, they proliferate as a consequence of disturbances which impact directly on these ecosystems. The most extensive ongoing disturbance since European occupation of Australia has been the disruption of frequent mild burning by humans. This burning maintained dynamically stable nutrient cycling processes and a competitive balance in dry and moist eucalypt systems and prevented plant “invasions”.
Structural Identification of O-Linked Oligosaccharides Using Exoglycosidases and MSn Together with UniCarb-DB Fragment Spectra Comparison
Authors: Ali Liaqat , Kenny Diarmuid T. , Hayes Catherine A. , Karlsson Niclas G.
Published: October 2012

The availability of specific exoglycosidases alongside a spectral library of O-linked oligosaccharide collision induced dissociation (CID) MS fragments, UniCarb-DB, provides a pathway to make the elucidation of O-linked oligosaccharides more efficient. Here, we advise an approach of exoglycosidase-digestion of O-linked oligosaccharide mixtures, for structures that do not provide confirmative spectra. The combination of specific exoglycosidase digestion and MS2 matching of the exoglycosidase products with structures from UniCarb-DB, allowed the assignment of unknown structures. This approach was illustrated by treating sialylated core 2 O-linked oligosaccharides, released from the human synovial glycoprotein (lubricin), with a α2–3 specific sialidase. This methodology demonstrated the exclusive 3 linked nature of the sialylation of core 2 oligosaccharides on lubricin. When specific exoglycosidases were not available, MS3 spectral matching using standards was used. This allowed the unusual 4-linked terminal GlcNAc epitope in a porcine stomach to be identified in the GlcNAc1-4Galb1–3(GlcNAcb1-6)GalNAcol structure, indicating the antibacterial epitope GlcNAca1–4. In total, 13 structures were identified using exoglycosidase and MSn, alongside UniCarb-DB fragment spectra comparison. UniCarb-DB could also be used to identify the specificity of unknown exoglycosidases in human saliva. Endogenous salivary exoglycosidase activity on mucin oligosaccharides could be monitored by comparing the generated tandem MS spectra with those present in UniCarb-DB, showing that oral exoglycosidases were dominated by sialidases with a higher activity towards 3-linked sialic acid rather than 6-linked sialic acid.
From Cycling Between Coupled Reactions to the Cross-Bridge Cycle: Mechanical Power Output as an Integral Part of Energy Metabolism
Authors: Diederichs Frank
Published: October 2012

ATP delivery and its usage are achieved by cycling of respective intermediates through interconnected coupled reactions. At steady state, cycling between coupled reactions always occurs at zero resistance of the whole cycle without dissipation of free energy. The cross-bridge cycle can also be described by a system of coupled reactions: one energising reaction, which energises myosin heads by coupled ATP splitting, and one de-energising reaction, which transduces free energy from myosin heads to coupled actin movement. The whole cycle of myosin heads via cross-bridge formation and dissociation proceeds at zero resistance. Dissipation of free energy from coupled reactions occurs whenever the input potential overcomes the counteracting output potential. In addition, dissipation is produced by uncoupling. This is brought about by a load dependent shortening of the cross-bridge stroke to zero, which allows isometric force generation without mechanical power output. The occurrence of maximal efficiency is caused by uncoupling. Under coupled conditions, Hill’s equation (velocity as a function of load) is fulfilled. In addition, force and shortening velocity both depend on [Ca2+]. Muscular fatigue is triggered when ATP consumption overcomes ATP delivery. As a result, the substrate of the cycle, [MgATP2−], is reduced. This leads to a switch off of cycling and ATP consumption, so that a recovery of [ATP] is possible. In this way a potentially harmful, persistent low energy state of the cell can be avoided.
Chemoresistance to Valproate Treatment of Bovine Leukemia Virus-Infected Sheep; Identification of Improved HDAC Inhibitors
Authors: Gillet Nicolas , Vandermeers Fabian , De Brogniez Alix , Florins Arnaud , Nigro Annamaria , François Carole , Bouzar Amel-Baya , Verlaeten Olivier , Stern Eric , Lambert Didier M. , Wouters Johan , Willems Luc
Published: October 2012

We previously proved that a histone deacetylase inhibitor (valproate, VPA) decreases the number of leukemic cells in bovine leukemia virus (BLV)-infected sheep. Here, we characterize the mechanisms initiated upon interruption of treatment. We observed that VPA treatment is followed by a decrease of the B cell counts and proviral loads (copies per blood volume). However, all sheep eventually relapsed after different periods of time and became refractory to further VPA treatment. Sheep remained persistently infected with BLV. B lymphocytes isolated throughout treatment and relapse were responsive to VPA-induced apoptosis in cell culture. B cell proliferation is only marginally affected by VPA ex vivo. Interestingly, in four out of five sheep, ex vivo viral expression was nearly undetectable at the time of relapse. In two sheep, a new tumoral clone arose, most likely revealing a selection process exerted by VPA in vivo. We conclude that the interruption of VPA treatment leads to the resurgence of the leukemia in BLV-infected sheep and hypothesize that resistance to further treatment might be due to the failure of viral expression induction. The development of more potent HDAC inhibitors and/or the combination with other compounds can overcome chemoresistance. These observations in the BLV model may be important for therapies against the related Human T-lymphotropic virus type 1.
Development Strategies for Herbal Products Reducing the Influence of Natural Variance in Dry Mass on Tableting Properties and Tablet Characteristics
Authors: Qusaj Ylber , Leng Andreas , Alshihabi Firas , Krasniqi Blerim , Vandamme Thierry
Published: October 2012

One “Quality by Design” approach is the focus on the variability of the properties of the active substance. This is crucially important for active substances that are obtained from natural resources such as herbal plant material and extracts. In this paper, we present various strategies for the development of herbal products especially taking into account the natural batch-to-batch variability (mainly of the dry mass) of tablets that contain a fixed amount of tincture. The following steps in the development have been evaluated for the outcome of the physico-chemical properties of the resulting tablets and intermediates: concentration of the tincture extracted from Echinacea fresh plant, loading of the concentrate onto an inert carrier, the respective wet granulation and drying step, including milling, and the adjuvant excipients for the tablet compression step. The responses that were investigated are the mean particle size of the dried and milled granulates, compaction properties and disintegration time of the tablets. Increased particle size showed a significant increase of the disintegration time and a decrease of the compaction properties. In addition, our results showed that the particle size has a great dependency on the ratio of liquid to carrier during the wet granulation process. Thus, the variability of the respective parameters tested was influenced by the performed strategies, which is how the tincture correlated to its dry mass and the relation of the amount of carrier used. In order to optimize these parameters, a strategy considering the above-mentioned points has to be chosen.
A Novel CD105 Determination System Based on an Ultrasensitive Bioelectrochemical Strategy with Pt Nanoparticles
Authors: Zeng Suyun , Wang Sujun , Wang Li , Yang Lihua , Chen Zhenbo , Liang Zhiqing
Published: October 2012

CD105 is a well-known tumor metastasis marker and useful for early monitoring of metastasis and cancer relapse. It is important to generate rapid, reliable and precise analytical information regarding CD105 levels. To establish a simple, selective and sensitive detection method, we prepared an immunosensor with novel bioconjugates based on Pt nanoparticles, thionin acetate and antibodies. The proposed immunosensor displayed a broader linear response to CD105, with a working range of 1.3 to 200.0 ng/mL and a detection limit of 0.9 ng/mL under optimal conditions. Moreover, the studied immunosensor exhibited high sensitivity, fast analysis and adequate stability. The proposed methodology could readily be extended to other clinical- or environment-related biospecies.
Design of a New Sensor for Determination of the Effects of Tractor Field Usage in Southern Spain: Soil Sinkage and Alterations in the Cone Index and Dry Bulk Density
Authors: Valera Diego L. , Gil Jesús , Agüera Juan
Published: October 2012

Variations in sinkage and cone index are of crucial importance when planning fieldwork, and for determining the trafficability of farm machinery. Many studies have highlighted the link between higher values of these parameters and dramatic decreases in crop yield. Variations in the dry bulk density and cone index of clayey soil in Southern Spain were measured following each of five successive passes over the same land with the three types of tractor most widely used in the area (tracked, two-wheel drive and four-wheel drive). In addition, sinkage (rut depth) of the running gear was measured using a laser microrelief profile meter. This device, which integrates three sensors, was specifically designed for these experiments, as was an electrical penetrometer to determine the cone index, and both instruments proved reliable and accurate in the field. The main goal of this study was to design, manufacture and test these new devices. The first pass caused most soil alteration when compared to successive passes for all types of tractor tested and soil conditions prevailing during the tests. (Heavier) four-wheel drive tractors were found to cause greater soil damage (sinkage, cone index and dry bulk density) than two-wheel drive and track tractors. There was no statistically significant difference between the two latter types. The greatest alterations were recorded in the top 10 cm of the soil. The results show that soil compaction should be avoided as much as possible. This can be achieved by ensuring that tractors always travel along the same tracks, especially in the wet season. At present these aspects are not considered by farmers in this area.
The Use of Events in the Developmnet of the Tourism Industry: The Case of Cyprus
Authors: Avgousti Kakia
Published: October 2012

Event tourism is a subject that has not passed through any intensive research in the case of Cyprus. The current research attempted to investigate the extent to which events contribute to the development of tourism in Cyprus. In more depth, the research study compared both primary and
secondary research on the subject of events, their importance, and their contribution to the development of tourism in Cyprus. In conclusion it highlighted the minimum contribution of events in the development of tourism in Cyprus as events are being used as supplements in the case of Cyprus,
and as a tool that will assist to the strengthening and enrichment of the existing tourism product. However, potentials and opportunities exist for further developments regarding this sector. In response to these, tourism organizations, authorities, and tourism bearers should become active
players and create such strategic plans, to develop events in means that will be fitted to the existing image of the island and thus improving, not changing, its tourism product.
Strong Ties within Cultural Organization Event Networks and Local Development in a Tale of Three Festivals
Authors: Izzo Francesco , Bonetti Enrico , Masiello Barbara
Published: October 2012

The purpose of this article is to provide a deeper understanding of successful event networks and offer a conceptual framework which can be used to analyze their impact on local development. In particular, this study addresses two research questions. First, how does network structure affect the success of the event and its outcomes on local development, other than in economic terms? Second, which main capabilities does the "network orchestrator" need to promote the effectiveness of the event network? By analyzing three different Italian cultural festivals—"Festivaletteratura" ("Festival of Literature"—Mantua), "Festival della Scienza" ("Festival of Science"—Genoa), and "Festivalfilosofia" ("Festival of Philosophy"—Modena, Carpi, Sassuolo)—this article sheds light on: (a) the features of successful event networks, (b) the dynamics linking network structure and the social outcomes generated, and (c) the typical bundle of relational capabilities that network orchestrators need. Then we draw some implications for management and offer some remarks to stimulate further research in the field of special events.
trans-2-(2,5-Dimethoxy-4-iodophenyl)cyclopropylamine and trans-2-(2,5-dimethoxy-4-bromophenyl)cyclopropylamine as potent agonists for the 5-HT2 receptor family
Authors: Pigott Adam , Frescas Stewart , McCorvy John D , Huang Xi-Ping , Roth Bryan L , Nichols David E
Published: October 2012

A strategy to replace the ethylamine side chain of 2,5-dimethoxy-4-iodoamphetamine (DOI, 1a), and 2,5-dimethoxy-4-bromoamphetamine (DOB, 1b) with a cyclopropylamine moiety was successful in leading to compounds with high affinity at the 5-HT2 family of receptors; and the more potent stereoisomer of the cyclopropane analogues had the expected (−)-(1R,2S)-configuration. Screening for affinity at various serotonin receptor subtypes, however, revealed that the cyclopropane congeners also had increased affinity at several sites in addition to the 5-HT2A and 5-HT2B receptors. Therefore, at appropriate doses – although (−)-4 and (−)-5 may be useful as tools to probe 5-HT2 receptor function – one would need to be mindful that their selectivity for 5-HT2A receptors is somewhat less than for DOI itself.
THE EFFECT OF SEASONAL CHANGE OF PLANTS COMPOSITIONS ON VISUAL PERCEPTION / SEZONINIO AUGALIJOS SUDĖTIES POKYČIO ĮTAKA VIZUALIAM SUVOKIMUI
Authors: Eroğlu Engin , Müderrisoğlu Haldun , Kesim Güniz Akıncı
Published: October 2012

Plants are important elements of open-green areas in the urban space and perception of an environment. Some plants have seasonal colour changes. The identification of these changes and clarification of the effects on people are quite important for landscape architecture. Seasonal changes of plants in some open-green areas in Düzce were examined in order to explain how it affects people regarding changes in perceptional preferences. Delphi Method was used on photographs as a mean of identification of the visual effects of the plant compositions. The plant composition photographs, which had been examined before, were used in the questionnaire to 370 student groups. As a result, the difference was evaluated between the perceiving of different plant compositions. Summer was the most affecting season having the design value and visual quality. Besides, evergreen plants had a positive effect on design power and visual quality of compositions. Furthermore, as another important result, it was found out that socio-economic levels of the people had some important effects on visual preferences. In this study, perceptional differences of the participants on seasonal changes of the plants were identified. Moreover, the form and the texture were evaluated for identifying perceptional effects. Santrauka Reikšmingas urbanizuotos teritorijos elementas yra želdynų augalija. Kai kurios augalų rūšys kintant sezonui keičia spalvas. Suvokiant šių pokyčių poveikį žmogui, svarbu tai pritaikyti kuriant kraštovaizdžio architektūrą. Sezoninių augalijos pokyčių poveikiui tirti pasirinkta ãtviros Düzce apylinkių vietos. Vizualiam augalijos poveikiui nustatyti taikytas Delphi fotonuotraukų metodas. Anksčiau vertintos nuotraukos buvo panaudotos apklausoje, kurioje dalyvavo 370 studentų grupių. Vertinti augalijos skirtingos sudėties suvokimo skirtumai. Nustatyta, kad didžiausią poveikį vizuali želdinių projektavimo kokybė daro vasaros sezoną. Respondentai, vertindami projektavimą ir vizualią augalijos sudėties kokybę, teigiamai pažymėjo visžalius augalus. Iš apklausų nustatyta, kad didelę įtaką vizualiam suvokimui turi socialiniai-ekonominiai žmonių skirtumai. Įvertinta ir projektuojamų želdinių formos bei sandaros reikšmė suvokiant vaizdo efektus.
IMPACT OF KLAIPĖDA PORT JETTIES RECONSTRUCTION ON ADJACENT SEA COAST DYNAMICS / REKONSTRUOTŲJŲ KLAIPĖDOS UOSTO MOLŲ ĮTAKA GRETIMŲ JŪROS KRANTŲ DINAMIKAI
Authors: Jarmalavičius Darius , Žilinskas Gintautas , Pupienis Donatas
Published: October 2012

During the reconstruction of 2001–2002, the Klaipėda port jetties were lengthened (the northern jetty by 205 m and the southern by 278 m). These works produced an impact on dynamic coastal processes in the neighbourhood of the port. The evaluation of the impact of jetties reconstruction was based on the data obtained in 1995–2010 during the monitoring of coastal dynamics in the port of Klaipėda. Study area includes 10 km coastal strip of mainland and 12 km coastal strip of Curonian Spit. The analysis of the data concerning the changes in the annual amount of coastal sediment served as a basis to evaluate the impact of Klaipėda port jetties on the trends in coastal dynamics prevailing before the reconstruction and their changes after it. It was found that in the mainland coastal stretch closest to the jetties, where in the last decade before jetties extension the seashore was relatively stable, the coastal erosion trends were dominant. Meanwhile, the closest to the jetties coastal stretch of the Curonion Spit, where erosion processes dominated in the last decade before jetties extension, stabilized right after the reconstruction and with a passage of time sediment accumulation trends have become prevailing. Santrauka 2001–2002 m. vykdant Klaipėdos jūrų uosto rekonstrukcijos darbus buvo prailginti molai (šiaurinis 205 m, pietinis – 278 m). Vertinant molų rekonstrukcijos įtaką jūros krantų greta uosto dinamikai remtasi nuo 1995 m. atliekamos jos stebėsenos duomenimis. Tyrimų rajonas apėmė 10 km ilgio žemyno kranto juostą ir 12 km ilgio Kuršių nerijos kranto juostą. Matavimai buvo atliekami 18 profilių žemyno krante ir 12 profilių Kuršių nerijos krante. Analizuojant kasmetinės kranto sąnašų kiekio kaitos duomenis įvertinta Klaipėdos uosto molų įtaka gretimų krantų dinamikos tendencijoms, vyravusioms iki molų rekonstrukcijos, ir jų pokyčiams po molų rekonstrukcijos. Nustatyta, kad žemyne, arčiausiai molų esančioje kranto atkarpoje, kurioje pastarąjį dešimtmetį iki uosto molų prailginimo krantas buvo santykinai stabilus, po rekonstrukcijos įsivyravo kranto ardos tendencijos. Kuršių nerijos krante, kur pastarąjį dešimtmetį iki molų prailginimo arčiausioje nuo molo kranto atkarpoje vyravo intensyviõs ardos procesai, po molų rekonstrukcijos krantas iš pradžių stabilizavosi, o vėliau čia pradėjo vyrauti sąnašų akumuliacijos tendencijos.
MODELLING THE NOISE GENERATED BY RAILWAY TRANSPORT: STATISTICAL ANALYSIS OF MODELLING RESULTS APPLYING CADNAA AND IMMIPROGRAMS / GELEŽINKELIO TRANSPORTO KELIAMO TRIUKŠMO MODELIAVIMAS IR STATISTINĖ REZULTATŲ ANALIZĖ
Authors: Paožalytė Ilona , Grubliauskas Raimondas , Vaitiekūnas Petras
Published: October 2012

To avoid a negative impact on human health, Lithuania, alike other countries, pays full attention to reducing noise in the environment. One of the implemented actions against noise sources and the way to reduce it is a composition of strategic maps. Research focuses on the performance of modelling noise dispersion employing CadnaA and IMMI software and proposes the analysis of the actuarial reliability of the above-mentioned programs. The dispersion of the noise generated by railway transport has been modelled in the dwelling area of Klaipeda railway station. The chosen zone covers a sector of 500 m in length and is situated at the distance of 150–200 m from this sector. Modelling noise dispersion maps applying both programs displayed that the maximum level of noise caused by day and night railway transport was registered near railway during both periods of time and varied from 75 to 80 dBA, whereas at the locations of 150–200 m that are more distant from the railway line, the level of noise gradually reduces and reaches the level of 35–50 dBA in cases CadnaA or IMMI programs are introduced. Program STATISTICA along with Mann Whitney U and Kolmogorov–Smirnov D non-parametric statistical tests were used for assessing the actuarial reliability of modelling programs used for noise dispersion. The obtained data indicate that the level of significance p was not exceeding the value of 0.05 in all cases. Santrauka Lietuvoje, kaip ir kitose šalyse, daug dėmesio skiriama triukšmui aplinkoje mažinti siekiant išvengti jo neigiamo poveikio sveikatai, aplinkos kokybei. Viena iš triukšmo ir jo poveikio mažinimo priemonių yra strateginių žemėlapių sudarymas. Tyrimo tikslas – atlikti triukšmo sklaidos modeliavimą programomis CadnaAir IMMI bei pateikti šių programų statistinio patikimumo analizę. Modeliuojama geležinkelio transporto triukšmo sklaida Klaipėdos geležinkelio stoties gyvenamojoje teritorijoje 500 m ilgio geležinkelio ruože ir per 150–200 m nuo jo. Modeliuojant geležinkelio transporto dieną ir naktį sukeliamo triukšmo sklaidą nustatyta, jog abiem nagrinėtais laikotarpiais abiejų programų pateiktuose triukšmo sklaidos žemėlapiuose didžiausias triukšmo lygis – nuo 75 iki 80 dBA fiksuojamas šalia geležinkelio bėgių. Tolstant nuo bėgių, triukšmo lygis tolygiai mažėja, 150–200 m atstumu siekia 35–50 dBA ir CadnaA, ir IMMI triukšmo sklaidos modeliuose – ir dieną, ir naktį. Triukšmo sklaidos modeliavimo programų patikimumas vertintas programa STATISTICA bei Mann Whitney U ir Kolmogorov–Smirnov D neparametrinės statistikos testais. Šie rodė, jog reikšmingumo lygmuo p visais atvejais neviršijo 0,05 reikšmės. Todėl teigiama, kad abiejų modeliavimo programų pateikti rezultatai patikimi.
SPECIFIC FEATURES OF GROUNDWATER CIRCULATION IN THE BOGGED BASIN OF RĖKYVA LAKE / POŽEMINIO VANDENS APYKAITOS PELKĖTAME RĖKYVOS EŽERO BASEINE YPATUMAI
Authors: Zuzevičius Algirdas , Galčiuvienė Kristina
Published: October 2012

Two mathematical models using MODFLOW software were developed to estimate water losses from the bogged Lake Rėkyva watershed which are happening due to the groundwater recharge and to evaluate the influence of peat deposit development on the lake and the natural belt of a raised bog protecting the lake. The modelling data lead to the following conclusions: (1) groundwater exploitation in the Šiauliai waterworks would increase the water losses from the boggy basin negligibly (from 7 to 9 mm/a when the total runoff is over 150 mm/a (2) the annual and long-term runoff and water level regimes in the raised bog, that separates the peat deposit from the lake as a 3 km long and 0.26 to 0.8 m wide belt, are rather variable. Depending on the season, from 80 to 95% of the runoff from it is formed in the 0.3–0.5 m thick top layer (acrotelm) distinguished by anomalously good filtration properties and porosity; (3) at the end of the peat deposit exploitation, the discharge from the protective bog to the lake presumably will reduce by 0.2–0.4 l/s (about 1% of the total lake runoff) and that from the bog to the peat deposit will increase by about 0.5 l/s (depending on the season, 1–15% of the total runoff from the bog); and (4) seasonal recharge of acrotelm is capable of counterbalancing the loss there-fore the status of protective bog will remain close to the actual one. Santrauka Didžiausio Lietuvoje 11,85 km2 ploto vandenskyrinio Rėkyvos ežero baseino nuostoliams, jam maitinant požeminius vandenis, bei piečiau eksploatuojamo durpyno poveikiui ežerui ir apsauginei aukštapelkės juostai vertinti MODFLOW priemonėmis sudaryti du matematiniai modeliai. Nustatyta: 1 – dėl požeminio vandens gavybos Šiaulių miesto vandenvietėse baseino nuostoliai gali padidėti nežymiai (nuo 7 iki 9 mm/a, kai bendras nuotėkis yra per 150 mm/a); 2 – metinis ir daugiametis nuotėkio bei vandens lygių aukštapelkėje režimas yra labai kaitus; pagrindinė aukštapelkės, kuri 3 km ilgio ir 0,26–0,8 km pločio juosta skiria durpyną nuo ežero, nuotėkio dalis (nuo 80 iki 95 % – priklausomai nuo sezono) formuojasi 0,3–0,5 m storio viršutiniame sluoksnyje (akrotelme), šiam sluoksniui būdingos anomaliai geros filtracinės savybės ir poringumas (iki 0,95); 3 – eksploatacijos pabaigoje, pasiekus durpyno klodo dugną, nuotėkis iš pelkės į ežerą gali sumažėti 0,2–0,4 l/s (apie 1 % bendrojo ežero nuotėkio), o į durpyną – padidėti apie 0,5 l/s (pagal sezoną – 1–15 % bendrosios pelkės vandens apykaitos); 4 – sezoninis akrotelmo maitinimas yra pakankamas, kad kompensuotų šiuos nuostolius, ir apsauginės pelkės būklė išliktų artima dabartinei.
Equivalent Mortar Volume (EMV) method for proportioning recycled aggregate concrete: Validation under the Spanish context and its adaptation to Bolomey methodology for concrete proportioning
Authors: Jiménez C. , Aponte D. , Vázquez E. , Barra M. , Valls S.
Published: October 2012

A new method for proportioning recycled aggregates concrete (RAC) is used to check its feasibility under the Spanish context. First, an extensive experimental campaign has been done, with the purpose of check and analyze the applicability of the EMV method with two Spanish recycled concrete aggregates (RCA). The aim of the second part of the investigation, was to elaborate an adaptation of the EMV method to Bolomey methodology (1), using a 20% weight replacement of coarse natural aggregates (NA) for RCA, and so, with this, comply with the Spanish Instruction for Structural Concrete (EHE 2008). Slump, air content, fresh and hardened densities, compressive strength and modulus of elasticity were determined and analyzed, in order to check the concrete properties. Finally, it was observed that, the EMV method is viable, and its adaptation, results in concrete mixes with similar or better properties than the natural aggregate concrete and RAC conventionally prepared.
The Research on the Coupling Relation between Flatness and Edge Drop for Tandem Cold Rolling Mill
Authors: Zhou Xiao Min , Wu Yun Feng , Mao Yang Jun
Published: October 2012

The flatness and edge drop control system is a coupled multivariable control system. Realizing the coupling relationship quantitative analysis and decoupling control of them is one of the most important parts of achieving the high-precision control. In this paper, the flatness and edge drop control abilities of all the control actuators are analyzed. The coupling relationship between flatness and edge drop is analyzed. The decoupling control method is proposed to realize the decoupling control of flatness and edge drop. Simulation results represent that the flatness and edge drop control performance is improved effectively.
Active Disturbance Rejection Control for Hydraulic Position Control System of High-Quality Cold Rolling Mill
Authors: Xiang Xiao Fei , Wang Zhe , Zhang Fei , Zhao Li
Published: October 2012

Active disturbance rejection controller (ADRC) instead of the conventional PID controller in the hydraulic position control system is proposed to satisfy high accuracy and speed requirements in cold rolling mill. Based on the simplified model, frequency-domain analysis of the two kinds of controllers is performed. The results show that ADRC produces better performances, such as bandwidth, stability margins. Because of the extended state observer (ESO) that can estimate and compensate the tracking system in real time, ADRC reduces the dependence on accurate mathematical model, improves anti-disturbance capability of the system, and maintains good dynamic characteristics. The simulation results verified the effect of the conclusion.
Flatness On-Line Preset Technology for Cold Rolling Mill
Authors: Wang Dong Cheng , Liu Hong Min
Published: October 2012

Generally, optimization algorithm is adopted by flatness preset theory model to get optimal preset parameters, and the optimization process needs to frequently call flatness prediction model which combines strip plastic deformation model with rolls elastic deformation model through iterative method. The calculation time of iterative course is long, and optimization algorithm will multiply the calculation time, so it is difficult to apply the flatness preset theory model on line. To solving the problem, a step-by-step method is put forward by this paper, which separates strip plastic deformation model from rolls elastic deformation model reasonably, and the calculation speed and stability are improved significantly. At the same time, a direct method to solve strips object gauge transverse distribution and a fast influence function method are deduced to reduce the calculation time of basic models. The research result is tested by a 1420 mm reversible CVC-high mill, and its precision, speed and stability meet the requirement of online preset, which shows well promotion value.
Research of the Roll Systems Flexural Coupling-Dynamic Modeling
Authors: Zhang Yang , Peng Yan , Sun Jian Liang
Published: October 2012

Rolling process is a typical and complex nonlinear dynamic one which determined by the couple-interaction of different physical attribute movements. Different forms of dynamic response will be reacted by the external excitation on mill system, such as the fluctuation of the rolling force. The vertical vibration and the roller axial flexural deformation, among these dynamic responses, are the main factors which would affect the strip after rolling quality. In order to exactly describe the roll systems vertical vibration and the roller axial dynamic property, this article is focused on the mathematical modeling of the roll systems vertical vibration and the lateral flexural vibration. Take the situation, the roll systems vertical vibration and the lateral flexural vibration occur simultaneously, into account, the authors build the lateral coupling-dynamic model of the roll system. Using numerical simulation method, the authors analyze the interaction between the roll systems vertical vibration and lateral flexural vibration.
Simulation and Analysis on Dynamic Response Characteristics of Six-High Rolling Mill Based on FEM
Authors: Mi Kai Fu , Zhang Jie , Li Hong Bo , Jia Sheng Hui , Chu Yu Gang
Published: October 2012

The vibration influence on the quality of strip for 2180mm six-high cold tandem rolling mill is discussed. The abnormal frequency of mill is analysis by spot examination. The methods of numerical computation and finite element method simulation by the ANSYS are adopted to set up dynamic model of six-high mill. At the same time, the natural frequency of mill and the response to mill at different excitation is calculated. Comparing the analysis results with the data from the experiment, the finite element models presented in the thesis were proved to be an efficient and valid way to simulate actual working conditions.
Key Technologies and Application of Automatic Control System for Wide Stainless Steel Hot Strip Rolling Line
Authors: Zhang Da Zhi , Kang Ming , Zhao Wei
Published: October 2012

Wide stainless steel hot strip line integrated with mechanical electric hydraulic equipments is a complicated large system. Automatic control system is very important for improving mill efficiency and products quality. The new equipments and technology are introduced. The characteristics of hot strip line and its requests for automation, the ideas of control system design, system structure and configuration are explained in detail. Multilevel system, 1000M high speed fabric Ethernet between levels, 640M high speed global data memory network between controllers, high speed Profibus_DP network between controller and equipments, hot machine backup strategy of L2,Tri-cyclic fabric Ethernet redundancy of L1 and other innovative design ideas,and L2 main mathematic models, L1 key control models are all applied in the system. The design ideas of this paper and integrated automatic control system has been applied on several stainless steel hot strip lines.
Seamless Tube in Stretch Reducing 3-D Thermal-Mechanical Coupling Analysis
Authors: Zhou Yan , Chen Jin Liang , Zhao Chun Jiang , Shuang Yuan Hua
Published: October 2012

Based on rolling technology of stretch reducing mill group, by using large-scale general-purpose finite element analysis software ANSYS/LS-DYNA, a 3D thermal mechanical coupled numerical calculation of stretch reducing process, stress field, strain field, temperature field and the distribution of wall thickness were obtained, as well as the distribution of asymmetrical metal deformation when pipe passing every mill. The results of numerical simulation provide a reasonable cause for uneven wall thickness distribution, guiding the design of stretch reducing process.
Research on Harmonic Response of Hydraulic Screwdown System on Modern Hot Rolling Mill
Authors: Ling Qi Hui , Yan Xiao Qiang , Zhang Yi Fang
Published: October 2012

In this paper, the dynamic mathematical model about the asymmetric three-potential four-way valve control asymmetric hydraulic cylinder is established, and a hot rolling mill hydraulic screwdown system simulation model is constructed to research the dynamic characteristics by MATLAB/Simulink. It is obtained that the displacement output curve of the hydraulic cylinder by changing the rolling different strip thickness. Finally contrasting the input and output spectrum curve, it found that given the vibration signal by hydraulic system can transfer to the hydraulic cylinder. At the same time it indicate that the computer simulation is the effective way that research the dynamic characteristics of the hydraulic screwdown.
Deformation Resistance of Alloy 2.25Cr1Mo0.25V of Heavy Cylinder for Hydrogenation Reactor
Authors: Zhang Bo , Peng Yan , Sun Jian Liang , Chen Su Wen , Liu Jian Jing
Published: October 2012

2.25Cr1Mo0.25V alloy steel of making heavy cylinder for hydrogenation reactor was taken as research subject. The compression experiment was carried out on Gleeble-3500 thermal simulator under different conditions of deformation temperature, strain rate and deformation degree. The relationship between deformation resistance and deformation temperature, strain rate, deformation degree was analyzed. Two different types (dynamic recovery and dynamic recristallization) of deformation resistance model were established through multiple nonlinear regression method. The relative error of deformation resistance between the calculated value and the measured value was under 10% and the maximum error of the rolling force between the calculated value and the measured value was 9.7%, which showed that this deformation resistant model was accurate and met industry requirements.
Simulation and Application of Molecular Dynamics in Materials Science
Authors: Peng Yan , Wang Su Fen , Zhang Yang , Gao Ya Nan
Published: October 2012

t was summarized the simulate of materials and application of molecular dynamics, it expounded the molecular dynamics to solve the problem of the basic idea, principle, modeling methods and its simulating methods, and discussed the typical organization performance control technology, the development for simulation aspects and its problems existing. Especially focused on the molecular dynamics system its dynamic simulation in materials microscopic-sized, attached the application of macro characteristics and micro structure. Through the research and analysis, it gave the main application direction in solving steel organization performance control by the method of molecular dynamics, faced with the problem and its future development trend.
Numerical Simulation and Experiment on Quenching Process of 718 Mould Steel with New Online Hardening Equipment
Authors: Liu Guo Yong , Zhu Dong Mei , Zhang Shao Jun , Gong Shi Chuang
Published: October 2012

A new type online hardening equipment for quenching has been developed by University of Science and Technology Beijing and Dongbei Special Steel Group in Dalian Special Steel Co., LTD., which consists of strong water jet, medium water jet, weak water jet, air-water spray and side water jet and has flexible cooling and control ability. Based on the equipment, the online quenching process of 718 mould steel is performed by numerical simulation and field experiment. The result of temperature field by numerical simulation agrees well with that of experiment, which can prove that numerical simulation can be very good guidance for field experiment. Experimental tempering hardness difference of 718 mould steel can be controlled within 2 HRC in the whole plate according to numerical simulation. Prediction technology can meet the different cooling rate control and make quenching process comply with preset quenching route to guarantee material microstructure and performance.
Smelting Period Shortening Practices in Process of Electric Arc Furnace Steelmaking
Authors: Liu Hai Yu , Li Jing , Ma Cui
Published: October 2012

From a global point of view, advocating EAF steelmaking means reducing the consumption of resources like iron ores, coke, water and so on and on the same time cutting down the emission of carbon dioxide and residue, which is good for the environment and corresponding to Sustainable Development Strategy. We hold that considering the shortage of electric power and scrap steel in our country, the application direction of EAF steelmaking should be manufacture of quality steel with high additional value and reducing operation cost by shortening smelting period. This paper, aimed at NISCO, GISE-ZIS and AISG who take shortening smelting period as the core subject, hot metal charging technology in EAF and coherent oxygen lance technology as effective technical measures, optimizing process flow, improving product quality and reducing operation cost as purpose; investigates their experience in developing modern EAF steelmaking technology.
Constitutive Relationship of TRIP780 Steel in Quenching Process
Authors: Cao Qiang , Zhang Qing Dong , Sun Chao Yang
Published: October 2012

To characterize the mechanical behavior of TRIP780 steel in quenching process, Uniaxial tensile tests are performed on Gleeble-3500 thermo-simulation machine at temperature 323K~1073K and corresponding stress-strain curves are obtained. The results show that flow stress is affected by deformation temperature significantly and declines with increasing temperature. Based on simplified and modified Zerrilli-Armstrong model, the impact factor of temperature with quadratic polynomial fitting is introduced and the constitutive relationships with temperature dependent are established. The accuracy of the constitutive equations is verified and the flow stress predicted by the proposed model is consistent with experimental results. Therefore, the constitutive model can be applied for numerical simulation of quenching process.
The Influence of Process Scheme on the Straightening Effect of Section Steel
Authors: Guan Ben , Zang Yong , Wang Yuan , Feng Sha , Liu Xiao Chan
Published: October 2012

By studying the geometrical features and the mechanical characters of the profiles during the roller leveling process and combining the basic elastic-plastic theories, a mechanical model is established which is suitable for analyzing elastic-plastic bending of the profile during roller leveling process. Using this model, the straightening effects have been analyzed under different roller leveling process schemes for the profiles which have typical initial curvatures. The analysis of roller leveling process confirms that the curvature ranges of the profiles can't converged infinitely under any process scheme because of the hereditary effects of residual stress, and the large deformation straightening process scheme has better profile convergence than the small one. Further analysis shows that the residual stress of specific section after straightening process with large deformation straightening process is lower than that with small one, and a diminishing bending process scheme is beneficial to the control of residual stress.
The Design and Implementation of Intelligent Distributed Computer Monitor-Control System for Full Hydraulic Plate Leveler
Authors: Ying Hu , Hao Xiao Hong , Huang Qing Xue , Zang Deng Yue , Sun Jiang Tao
Published: October 2012

This paper describes the distributed control system design and implementation of third-generation leveler. The system is based on multiple field-buses, and consisted of many distributed computer control system, such as automation station, main operating station, monitoring station, engineers stations and so on. Through PLC control frequency converter, the system has realized the speed of transmission motor and tension control. And through the hydraulic position control loop, the system has realized the roll gap setting and maintained constant pressure. Because of this, in the head and tail, the steel have gained well straightening quality. The plate factory of a steel company used the four-fold hydraulic reversible 11 rolls leveler that is developed by the Taiyuan University of Technology. Through the practice proved, the control system is running well and meeting the control requirement of third-generation leveler.
On-Line Determination of Texture in Deep Drawing Steel Sheet by Two-Dimensional X-Ray Diffraction
Authors: Yin An Min , Yang Quan , Wang Xiao Chen , He Fei , Sun You Zhao
Published: October 2012

This paper described the application of a diffraction system based on X-ray area detector on pole figure measurement as well as corresponding computation of orientation distribution functions and the principle of rapid measurement texture. The impact of calculates the orientation distribution function on the conditions of the two-dimensional X-ray diffraction was analyzed; this was illustrated by an example of deep drawing steel sheets texture measurement. ̙̈́˰͇̱̓˰̶̴̿̾ͅ˰̸̱̈́̈́˰̷̱̹͂̿̈́̈́̾˰̸̵̈́˰͇̈́̿˽̴̵̹̹̱̼̽̾̓̿̾˰̴̵̵̳̈́̈́̿͂˰̈́̿˰̸̵̈́˰̵̱̹̱̀̀͂̿̀͂̈́˰̂θ position then fix it, reduce the sample rotation; the texture determination time can be significantly reduced. Reduce the Measuring range of angle χ˰̴̱̾ φ˰̴̵̿̓˰̾̿̈́˰̶̶̵̱̳̈́˰̸̵̈́ calculation of orientation distribution function, it also can significantly reduce the measurement of diffraction data. Several technical problems appeared on the on-line determination of texture based on an X-ray two-dimensional detector system and the possibility to improve the measurement speed and accuracy in the industrial production applications were then discussed.
Study on Design Parameters of Whole-Roll Shape Detecting Roll
Authors: Wu Hai Miao , Liu Hong Min
Published: October 2012

For the shape defects detection problem of the cold-rolled strip, the design parameters of whole-roll shape detecting roll were studied. The pre-pressure models were derived with the theory of elasticity and shell mechanics, and the pressure transmission performance of shape detecting roll was calculated. The correctness of the theoretical formula was verified by experiment. The design parameters presented by this paper would help to further improve the design standards and performance of the whole-roll shape detecting roll.
The Ultrasonic Detection of Macro-Inclusions in Steel
Authors: Wang Min , Bao Yan Ping , Yang Quan , He Fei , Wang Xiao Chen , Ma Cui , Liang Zhi Guo
Published: October 2012

This paper studied the distribution of defects by ultrasonic testing and the source of the defect was verified by SEM/EDS. The results showed that the defects mainly distributed in inner and outer sides closed to the surface of the slabs. The number of the defects in inner side was 1.5~2 times of that in outer side. A window 40mm×180mm inclusion band in 1/8 of the inner side existed. The defects in hot-rolled plate mainly formed due to the bad plasticity and deformability inclusions, such as Al2O3, SiO2 and MgO·xCaO. So decreasing the inclusions in slab was important to decrease the defects in hot-rolled plate.
Source Location of Cracks in a Working Roll of the Temper Mill with Acoustic Emission Technology
Authors: Lu Qiao Qiao , Li Min , Wang Xiao Jing
Published: October 2012

The application of the temper mill is mainly to improve the mechanical property of strip and to rectify the shape of strip. The working roll of a temper mill is often running with alternating load that prone to lead to faults such as wear, crack and spalling, which cause severe quality problems in the production of strip steel. In order to gain the information of crack's location and depth, the proposed method employs two circles of AE sensors along the direction of the roll body and use static pressure as external loads together with time-of-arrival localization method to detect the exact location of the roll cracks. The positioning results confirmed the validity of the proposed method with the post-repair grinding data. The advantage of this detection method is not requiring the full roll body scan point by point. With only one layout of the sensors, the method can detect the crack location with high efficiency and good real-time property.
Cold Rolling Backup Roller Bearing Temperature Remote Monitoring Method Based on Wireless Sensor Network
Authors: Yang Jian Hong , Xu Zhi Yuan , Gao En Yun , Yang Xin Bing , Xie Xue Guang , Wang Jin Xing
Published: October 2012

Aiming at the problems, such as difficulties in deployment and immovability during roller changing, which exist in traditional cold rolling backup roller bearing temperature monitoring technologies, a new temperature remote monitoring method based on wireless sensor network (WSN) is proposed. With a structure design of high water resistant and anti-vibration level, the monitoring sensor node can adapt to hot, humid and vibrating working environment. Autonomous power supply and wireless communication facilitate the installation of sensor nodes and bring good movability to sensor nodes. The topologic structure of the WSN is multi-layered and cluster-based. The cluster layer is mesh style, which can guarantee valid data communication while the sensor nodes moving into and out from the network during backup roller changing. Inside a cluster, star style network topology and the time division multiple access (TDMA) communication protocol are used to reduce node energy consumption and to prolong the network life. Remote communication between WSN and enterprise local area network is realized through a multi-hop relay tactic. Practical application in industrial fields shows that the proposed method is efficient to deal with the harsh and complicated operation environment, which is of great significance to monitoring bearing working condition accurately and in time.