bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy Consumption and Control Response Evaluations of AODV Routing in WSANs for Building-Temperature Control
Authors: Booranawong Apidet , Teerapabkajorndet Wiklom , Limsakul Chusak
Published: June 2013

The main objective of this paper is to investigate the effects of routing protocols on wireless sensor and actuator networks (WSANs), focusing on the control system response and the energy consumption of nodes in a network. We demonstrate that routing algorithms designed without considering the relationship between communication and control cannot be appropriately used in wireless networked control applications. For this purpose, an ad-hoc on-demand distance vector (AODV) routing, an IEEE 802.15.4, and a building-temperature control system are employed for this exploration. The findings from our scenarios show that the AODV routing can select a path with a high traffic load for data transmission. It takes a long time before deciding to change a new route although it experiences the unsuccessful transmission of packets. As a result, the desirable control target cannot be achieved in time, and nodes consume more energy due to frequent packet collisions and retransmissions. Consequently, we propose a simple routing solution to alleviate these research problems by modifying the original AODV routing protocol. The delay-threshold is considered to avoid any congested connection during routing procedures. The simulation results demonstrate that our solution can be appropriately applied in WSANs. Both the energy consumption and the control system response are improved.
Symmetries Shared by the Poincaré Group and the Poincaré Sphere
Authors: Kim Young , Noz Marilyn
Published: June 2013

Henri Poincaré formulated the mathematics of Lorentz transformations, known as the Poincaré group. He also formulated the Poincaré sphere for polarization optics. It is shown that these two mathematical instruments can be derived from the two-by-two representations of the Lorentz group. Wigner’s little groups for internal space-time symmetries are studied in detail. While the particle mass is a Lorentz-invariant quantity, it is shown to be possible to address its variations in terms of the decoherence mechanism in polarization optics.
Degradation of Aflatoxin B1 during the Fermentation of Alcoholic Beverages
Authors: Inoue Tomonori , Nagatomi Yasushi , Uyama Atsuo , Mochizuki Naoki
Published: June 2013

Aflatoxin B1 (AFB1) is a contaminant of grain and fruit and has one of the highest levels of carcinogenicity of any natural toxin. AFB1 and the fungi that produce it can also contaminate the raw materials used for beer and wine manufacture, such as corn and grapes. Therefore, brewers must ensure strict monitoring to reduce the risk of contamination. In this study, the fate of AFB1 during the fermentation process was investigated using laboratory-scale bottom and top beer fermentation and wine fermentation. During fermentation, cool wort beer samples and wine must samples were artificially spiked with AFB1 and the levels of AFB1 remaining after fermentation were analyzed. AFB1 levels were unchanged during both types of fermentation used for beer but were reduced to 30% of their initial concentration in wine. Differential analysis of the spiked and unspiked wine samples showed that the degradation compound was AFB2a, a hydrated derivative of AFB1. Thus, the results showed that the risk of AFB1 carryover was still present for both types of beer fermentation but was reduced in the case of wine fermentation because of hydration.
Histone Deacetylases in Herpesvirus Replication and Virus-Stimulated Host Defense
Authors: Guise Amanda , Budayeva Hanna , Diner Benjamin , Cristea Ileana
Published: June 2013

Emerging evidence highlights a critical role for protein acetylation during herpesvirus infection. As prominent modulators of protein acetylation, histone deacetylases (HDACs) are essential transcriptional and epigenetic regulators. Not surprisingly, viruses have evolved a wide array of mechanisms to subvert HDAC functions. Here, we review the mechanisms underlying HDAC regulation during herpesvirus infection. We next discuss the roles of acetylation in host defense against herpesvirus infection. Finally, we provide a perspective on the contribution of current mass spectrometry-based “omic” technologies to infectious disease research, offering a systems biology view of infection.
A Preliminary Investigation of Wastewater Treatment Efficiency and Economic Cost of Subsurface Flow Oyster-Shell-Bedded Constructed Wetland Systems
Authors: Yam Rita , Hsu Chia-Chuan , Chang Tsang-Jung , Chang Wen-Lian
Published: June 2013

We conducted a preliminary investigation of wastewater treatment efficiency and economic cost of the oyster-shell-bedded constructed wetlands (CWs) compared to the conventional gravel-bedded CW based on field monitoring data of water quality and numerical modeling. Four study subsurface (SSF) CWs were built to receive wastewater from Taipei, Taiwan. Among these sites, two are vertical wetlands, filled with bagged- (VA) and scattered- (VB) oyster shells, and the other two horizontal wetlands were filled with scattered-oyster shells (HA) and gravels (HB). The BOD, NO3−, DO and SS treatment efficiency of VA and VB were higher than HA and HB. However, VA was determined as the best option of CW design due to its highest cost-effectiveness in term of BOD removal (only 6.56 US$/kg) as compared to VB, HA and HB (10.88–25.01 US$/kg). The results confirmed that oyster shells were an effective adsorption medium in CWs. Hydraulic design and arrangement of oyster shells could be important in determining their treatment efficiency and cost-effectiveness. A dynamic model was developed to simulate substance transmissions in different treatment processes in the CWS using AQUASIM 2.1 based on the water quality data. Feasible ranges of biomedical parameters involved were determined for characterizing the importance of different biochemical treatment processes in SSF CWs. Future work will involve extending the experimental period to confirm the treatment efficiency of the oyster-shell-bedded CW systems in long-term operation and provide more field data for the simulated model instead of the literature values.
Homolytic substitution at phosphorus for C–P bond formation in organic synthesis
Authors: Yorimitsu Hideki
Published: June 2013

Organophosphorus compounds are important in organic chemistry. This review article covers emerging, powerful synthetic approaches to organophosphorus compounds by homolytic substitution at phosphorus with a carbon-centered radical. Phosphination reagents include diphosphines, chalcogenophosphines and stannylphosphines, which bear a weak P–heteroatom bond for homolysis. This article deals with two transformations, radical phosphination by addition across unsaturated C–C bonds and substitution of organic halides.
APPLICATION OF OTT'S MINE COORDINATE SYSTEM IN THE PAST AND IN PRESENT DAY
Authors: Staňková Hana , Černota Pavel
Published: June 2013

The coal district system of coordinates for mines located in the Ostrava region was established in 1858 by Dipl. Ing. František Ott, Surveyor of the Emperor Ferdinand Northern Railway (Severní dráha Ferdinandova). Coordinates of all significant points of existing mine shafts, characteristic mine surface points, and points in terrain, were determined by establishing mine triangulation within the Western part of the Ostrava-Karviná Coal District (OKR) on an area comprising almost 58 km2. Said points were stabilized by granite stones. The reason to establish this system of coordinates was to determine the points of a uniform basis of coordinates for making surveys both on the mine surface, i.e. for connecting the underground mine working, and simultaneously for removing any discrepancies occurring with respect to mine boundaries among particular proprietors, i.e. to allow for exact demarcation of mine areas bestowed to them by the state. Thus, nowadays Ott's system of coordinates that used to be applied during the period, in which within the OKR redevelopment works took place, like abatement the coal mining consequences.
ESTIMATING SLOPE FROM RASTER DATA – A TEST OF EIGHT ALGORITHMS AT DIFFERENT RESOLUTIONS IN FLAT AND STEEP TERRAIN
Authors: Tang Jing , Pilesjö Petter , Persson Andreas
Published: June 2013

Different slope algorithms can result in totally different estimates. In the worst case, this may lead to inappropriate and useless modelling estimates. A frequent lack of awareness when choosing algorithms justifies a thorough comparison of their characteristics, making it possible for researchers to select an algorithm which is optimal for their purpose. In this study, eight frequently used slope algorithms applied to Digital Elevation Models (DEMs) are compared. The influences of the resolution of the DEM (0.5, 1, 2, and 5 metres), as well as the terrain form (flat and steep terrain), are considered. It should be noted that the focus of the study is not to compare estimates with ‘ground truth’ data, but on the comparisons between the algorithms, and the ways in which they might differ depending on resolution and terrain. Descriptive statistics are calculated in order to characterize the general characteristics of the eight tested algorithms. Eight combinations of DEM resolution and terrain form are analysed. The results show that the Maximum and Simple Difference algorithms always yield higher mean slope values than the other algorithms, while the Constrained Quadratic Surface algorithm produces the lowest values compared to the others. It is concluded that the estimated slope values are heavily dependent on the number of neighbouring cells included in the estimation. An Analysis of Variance (ANOVA) of estimated slope values strongly indicates (at the significance level of 0.01) that the tested algorithms yield statistically different results. The eight algorithms produce different estimates for all tested resolutions and terrain forms but one. The differences are more pronounced in steep terrain and at a higher resolution. More detailed pairwise comparisons between estimated slope values are also carried out. It is concluded that the smoothing effects associated with the Constrained Quadratic Surface algorithm are greater in steeper terrain, showing significantly lower estimates than other algorithms. On the other hand, the Maximum and Simple Difference algorithms show significantly higher estimates in almost all cases, except the combination of steep terrain and low resolution. With an increase in grid cell size, the loss of information contents in DEMs leads to lower estimated slope values as well as smaller relative differences between algorithms. Based on the results of this study it is concluded that the choice of algorithm results in different estimated slope values, and that resolution and terrain influences these differences significantly.
MAPPING THE UNDISCOVERED OBJECTS AND SITES IN LITHUANIA
Authors: Jasiūnas Justinas , Maneikaitė Edita , Venckus Paulius , Romanovas Denis , Beconytė Giedrė
Published: June 2013

Forlorn, uncared-for cultural or natural objects and sites fail to be included into lists of touristic attractions due to their obscurity, poor condition and communication and are usually visited by certain social groups (extreme adventure travellers, members of various subcultures and etc.). The analysis revealed a wide array of such objects and sites, which are unknown and not in very good condition, can be very different starting with manor houses, historic parks and gardens and finishing with airfields, open courses or dumping grounds. The goal of a pilot research project carried out at the National Centre of Remote Sensing and Geoinformatics “GIS-Centras” was to collect information on diverse objects and sites that are typically not included into official information sources and fall outside the tourist infrastructure network. The collected information will be published as a map service. The inventory of such undiscovered objects and sites and visualisation is one of the ways to encourage the interest of visitors, especially in regions that lack famous tourist attraction objects or beautiful landscapes. The paper describes solutions for the structure of the database, object acquisition technology, cartographic visualisation and publication of collected data as an online map at www.nemasinis.lt ...
AUTHENTIC COMPASSION? O. TOSCANI'S OUTRAGEOUS CAMPAIGNS: AN ETHIC-ESTHETICAL INQUIRY FROM A THEOLOGIAN'S PERSPECTIVE / AUTENTIŠKAS GAILESTIS? ĮŽEIDŽIANČIOS O. TOSCANI KAMPANIJOS: ETINIS-ESTETINIS TYRINĖJIMAS IŠ TEOLOGO PERSPEKTYVOS
Authors: Enxing Julia
Published: June 2013

This article presents an ethical-esthetical examination of Oliviero Toscani's shocking photographs. Thereby it shortly introduces Toscani's life and work and proceeds with a description and analysis of three of his major works: the photographs of the anorexic model Isabelle Caro; the advertisement photographs for the jesus-jeans as well as the UNHATE campaign – one of his photo series for United Colors of Benetton. The article aims to point out the ethical implications of his works, especially from a theologian's perspective. It picks up relevant ethical theories and methods of evaluation, such as the principle of double action (Peter Knauer).

Santrauka

Šiame straipsnyje pateikiamas šokiruojančių Oliviero Toscani fotografijų etinis-estetinis tyrinėjimas. Čia skaitytojas trumpai supažindinamas su Toscani gyvenimu ir darbais, pradedant nuo trijų svarbiausiųjų aprašymo ir analizės: anoreksija sergančio modelio Isabelle's Caro fotografijų, džinsų reklaminių fotografijų su Jėzaus atvaizdais, taip pat UNHATE kampanijos – vienos jo fotografijų serijos, skirtos United Colors of Benetton. Taip iš teologo perspektyvos šiame straipsnyje siekiama atkreipti dėmesį į numanomas jo darbų etines reikšmes. Tam pasitelkiamos tam tikros etikos teorijos ir vertinimo metodai, tokie kaip dvigubos pasekmės principas (Peteris Knaueris).
CONCERNING A FLOWERY TABLECLOTH AND THE COMPUTER-AIDED ANALYSIS OF A 19TH-CENTURY PHOTOGRAPHIC IMAGE / APIE GĖLĖTĄ STALTIESĘ IR XIX AMŽIAUS FOTOGRAFIJOS KOMPIUTERINĘ VAIZDO ANALIZĘ
Authors: Žaltauskaitė Vilma , Žiūrienė Rytė
Published: June 2013

The paper introduces some peculiarities of the analysis of the photographic image which emerged in the process of the investigation and preparation for publication of the album of prelate Povilas Januševičius’ the end of 19th – beginning of 20th century. Miscellaneous analysis of photograph image is presented. It also introduces how problems of photograph dating could be solved by combining in sights of investigator as well as application of information technology. Among other things a technological study is being presented in which similarity of flowered tablecloth was analysed in different photographs. Up-to-date programs for processing and analyzing images open up completely new possibilities leading to automatic recognition and identification of objects, symbols and faces. Santrauka Straipsnyje supažindinama su kai kuriomis senosios fotografijos datavimo problemomis, kurios iškilo rengiant publikavimui ir analizuojant bei komentuojant prelato Povilo Januševičiaus XIX amžiaus pabaigos – XX amžiaus pradžios fotografijų albumą. Pateikiama fotografijų vaizdo, fotografijų fotokortelių analizė. Supažindinama, kaip būtų galima spręsti fotografijų datavimo problemas, derinant tyrėjo įžvalgas ir pasitelkiant informacines technologijas. Taip pat pateikiamas technologinio pobūdžio tyrimas, kurio metu buvo tikrinamas gėlėtos staltiesės panašumas skirtingose nuotraukose. Šiuolaikinės vaizdo apdorojimo ir analizės programos suteikia kokybiškai naujas galimybes, kada tampa įmanomas automatizuotas objektų, simbolių ar veidų atpažinimas ir identifikavimas.
Vases à parfum de la fin de l'époque classique mis au jour à Apollonia de Cyrénaïque : les analyses de contenus
Authors: Maffre Jean-Jacques , Frère Dominique , Garnier Nicolas , Dodinet Elisabeth
Published: June 2013

Les analyses chimiques de contenus organiques ne sont pas encore systématiques, mais sont de plus en plus sollicitées dans le cadre de problématiques liées aux activités de production, de transformation de matières premières, aux méthodes et pratiques de stockage, de transport, de conservation, de consommation, et aux rituels d’offrandes faites aux divinités et aux défunts. Une campagne de prélèvements a eu lieu à Apollonia de Cyrénaïque en 2008 dans le cadre de la Mission archéologique française en Libye, alors dirigée par André Laronde. Un peu plus d’une douzaine de vases à parfum de la fin de l’époque classique et du début de l’époque hellénistique ont été sélectionnés afin de procéder à l’analyse chimique de leurs contenus organiques. Cet article présente les résultats de ces analyses et leurs interprétations botaniques et archéologiques. Il en ressort que les contenus des vases en céramique se différencient de ceux en albâtre et sont composés de substances grasses aromatiques à dimension cosmétique et médicinale, avec des matériaux d’origine végétale mais aussi animale.
Les sens de la représentation politique : usages et mésusages d'une notion
Authors: Sintomer Yves
Published: June 2013

Résumé Contre la tentation de proposer une définition de l’essence de la représentation, il s’agit de dégager différentes notions en partant des mots utilisés par les acteurs et en les soumettant à un processus d’abstraction. La prise de distance avec la trompeuse familiarité du mot, appuyée sur les travaux historiens, vise en retour à donner des instruments pour penser les transformations du présent au-delà de la représentation-mandat. Quatre couples conceptuels sont ainsi proposés : représentation symbolique vs. représentation juridico-politique, présentification d’un absent vs. exhibition d’une présence, représentation- mandat vs. représentation-incarnation, et représentation-distinction vs. représentation descriptive. Ils renvoient à des logiques idéal-typiques qu’il convient de distinguer analytiquement, même si elles peuvent et doivent être articulées pour comprendre les événements ou les dispositifs concrets.
Les Noirs doivent-ils être représentés par des Noirs et les femmes par des femmes ?
Authors: Mansbridge Jane Jebb , Saint-Upéry Marc
Published: June 2013

Résumé Les groupes désavantagés peuvent tirer bénéfice de la représentation descriptive dans au moins quatre contextes. Dans les contextes de méfiance discriminatoire à l’encontre d’un groupe et de faible cristallisation de ses intérêts, la compétence expérientielle et communicationnelle supérieure des représentants de type descriptif ouvre la voie à une meilleure représentation substantielle des intérêts dudit groupe en améliorant la qualité de la délibération. Dans les contextes de subordination politique historique et de faible légitimité empirique, la représentation descriptive contribue à engendrer une perception sociale de « compétence politique » du groupe et renforce l’attachement de ses membres au système politique et à ses institutions. Bien que la mise en oeuvre de la représentation descriptive implique des coûts sur le plan d’autres valeurs, ces externalités négatives s’avèrent toutefois plus acceptable dans ces contextes historiques spécifiques.
Démocratie radicale et tirage au sort
Authors: Cervera-Marzal Manuel , Dubigeon Yohan
Published: June 2013

Résumé Longtemps ignoré par la science politique, le tirage au sort revient depuis quelques années sur le devant de la scène, apportant de ce fait un éclairage nouveau à la question démocratique. Il était traditionnellement admis, depuis Aristote et Montesquieu, que le tirage au sort comme méthode de désignation des représentants possédait des effets démocratiques et anti-oligarchiques. Pourtant, le regain d’intérêt des élites politiques et de certains théoriciens du gouvernement représentatif pour le tirage au sort, ainsi que sa récente utilisation expérimentale à Porto Alegre ou en Colombie britannique, ne constituent-ils pas un démenti factuel à la thèse aristotélo-montesquienne d’une antinomie fondamentale entre tirage au sort et libéralisme ? Tout en s’écartant de l’hypothèse essentialiste d’une nature du tirage au sort, cet article prend le contrepied d’un certain discours libéral qui, insistant exagérément sur la vertu neutralisantedu sort, en vient à occulter sa vertu égalitaire, sa portée subversive et son lien avec l’idée de démocratie radicale. L’hypothèse d’un tirage au sort libéral est mise à mal par les approches historiques, sociologiques et philosophiques du sujet.
Efectos de los fallos en la compra ‘online’ sobre la satisfacción con la página web: análisis de las distintas respuestas según las características demográficas del consumidor
Authors: Pascual del Riquelme Martín María Isabel , Román Nicolás Sergio , Fernández Sabiote Estela
Published: June 2013

Consumer dissatisfaction after experiencing an online service failure is the main reason for customers abandoning online purchases. However, not all consumers respond to these situations in the same way. The aim of this study is to identify segments of consumers according to their different satisfaction with online shopping, from the dual perspective of having experienced or not, a service failure in the purchase. Results, from a sample of 397 online consumers, confirm that the effect of online service failures in consumer satisfaction differs based on consumers’ gender and age, providing valuable information for online retailers to effectively implement market segmentation strategies.
The influence of the transformational leadership in the organizational trust
Authors: Martins Marques de Lima Rua Orlando Manuel , Costa Araújo João Manuel
Published: June 2013

The aim of this paper is to analyze the influence of transformational leadership on organizational trust. For that we develop a case study following a quantitative methodological approach. The research was conducted at the Serralves Foundation (Porto, Portugal) to empirically test the proposed research model and its hypotheses. The empirical results confirm that transformational leadership positively influences organizational trust in all its components (benevolence, competence and integrity). These may assist cultural organizations in defining the most appropriate leadership styles that could lead to high levels of trust. As the main limitation of this study, we highlight the fact that it does not consider the leaders’ perspective on their subordinates’ behaviour.
Editorial Letter from the Director
Authors: Civera Gibert Montserrat
Published: June 2013

Carta de la Directora Editorial
E-Government Diffusion
Authors: Ngafeeson Madison N. , Merhi Mohammad I.
Published: July 2013

The use of technology to offer goods and services by governments to citizens has been a growing phenomenon in the last decade. Many projects have been recorded across nations in an effort to encourage the adoption and diffusion of e-government. However, these studies have been rather isolated project reports than a comprehensive global picture. This study examines the e-government diffusion across 192 countries in the last decade. The panel data obtained is analyzed to evaluate the current state of e-government diffusion. Evidence in the last decade suggests that the difference in e-government diffusion is wider from country to country, than from year to year, within the same country and that country-specific effects account for these differences. The authors discuss the implications of these findings.
Implementation of Penicillium sp. as Raw Material for Synthesizing Metal Nanoparticles for Antibiosis
Authors: Nayak B.K. , Bhat M. Amin , Nanda Anima
Published: July 2013

Silver Nanoparticles (Ag-NPs) have been known to have inhibitory and bactericidal effects. Resistance to antimicrobial agents by pathogenic bacteria has emerged in recent years and is a major health problem. The ability of some microorganisms such as bacteria and fungi to control the synthesis of metallic Nanoparticles should be employed in the search for new materials. The present work is the study of biosynthesis of silver Nanoparticles synthesized from differentPenicilliumspp.ThePenicilliumspecies were identified by employing microscopic methods and laboratory manuals. The Nanoparticles synthesis was done by extracellular and intracellular methods. The silver Nanoparticles formed were characterized by Uv-vis spectrophotometer followed by TEM analysis. The maximum absorbance 410nm confirmed the formation of silver Nanoparticles and TEM revealed the particle size in the range of 30-40nm, which after confirmation was checked for its antibacterial activity against selected microbial pathogens likeBacillus cereus, Proteus vulgaris, Staphylococcus aureusandStaphylococcus epidermidis.The Nanoparticles synthesized byPenicilliumspecies showed a well anti microbial activity that was further compared with different antibiotics to check the Nanoparticles activity which can be substituted in place of high dose antibiotics.
Hydroxyapatite Nanocomposites for Biological Application
Authors: Kumar J.
Published: July 2013

Hydroxyapatite is a bioceramic which has a wide range of medical application for bone diseases. To enhance its usage, we have prepared ciprofloxacin loaded nanohydroxyapatite (HA) composite with a natural polymer, alginate, using wet chemical method at low temperature. The prepared composites were analyzed by various physicochemical methods. The results show that the nanoHA crystallites are well intact with the alginate macromolecules. For the composite system FT-IR study is done. The drug is pre-adsorbed onto the ceramic particle before the formation of composite. The thermal behavior of composite has been studied using thermo gravimetric analysis (TGA). This paper communicated the Influence of Polymer concentration on the Controlled drug release from hydroxyapatite Nanocomposites
Dispersion and Impact Strength of Epoxy Resin/Nano-Al2O3 Composites
Authors: Gao Nai Kui , Xu Zhou , Wu Chun , Li Rui Hua , Jin Hai Yun
Published: July 2013

This paper focuses on the influence of nano-Al2O3 surface state and composite process on the dispersion of nano-Al2O3 filler. Toughening was performed to epoxy resin by nano-Al2O3, and the effect of impact property of epoxy resin/nano-Al2O3 composites was studied. The results showed that coupling agent treatment and high-speed shear dispersion can improve many properties of the composites. With nano-Al2O3 content increasing, the impact strength of the composites increased at first and then decreased. The maximum appears when the nano-Al2O3 content reached 3wt. %, no matter with or without the coupling agent treatment, which is 87.4% and 78.6% higher than that of monolithic epoxy resin respectively. The coupling agent treatment of nano-Al2O3 helped to improve the impact strength of the composites.
Nitrogen Doping to Metatitanic Acid by NH3 Heat Treatment for Achieving Visible-Light-Responsive Photocatalytic Activity
Authors: Park Se Keun , Eun Jun Ho , Shin Hyun Ho
Published: July 2013

Nitrogen doping can be achieved by heating TiO2-based photocatalyst powders under dopant-generating atmospheres such as NH3. In the present work, metatitanic acid (MTA) powder was used as a raw material to obtain nitrogen-doped titania using heat treatment in NH3flow. MTA is an industrially available intermediate product in sulfate process for TiO2production, which is mesoporous material with high specific surface area. The MTA powder was heat-treated in flowing NH3at 400–550°C. For comparison, commercial P25 TiO2powder was heat-treated under the same conditions. The results show that nitrogen dopant can be successfully incorporated into the MTA by heating in NH3 atmosphere. This obviously results in the enhanced visible-light photocatalytic activity, especially in MTA sample heated at 400°C. Due to the fascinating properties of MTA powder such as high specific surface area, the N-doping effect on MTA powder is much higher than the P25 TiO2powder.
Study of the Effect of Thermomechanical Processing on Grain Refinement in HSLA Steels
Authors: Muszka Krzysztof , Majta Janusz , Dziedzic Dominik
Published: July 2013

The present study highlights the approach to multiscale analysis of the grain refinement during thermomechanical processing of microalloyed steels. HSLA steels for pipe-line use are introduced in which strain-induced precipitation and strain-induced transformations are controlled to produce ultra-fine grained microstructures. Multiscale modeling combining Digital Material Representation and Crystal Plasticity enables to gain a better fundamental understanding of mechanical response and microstructure evolution of precipitation strengthened austenite and ferrite of three microalloyed steel grades. The opportunities for the development of new thermomechanical processing schedules, focused on the grain refinement, are enhanced and the proposed models identifications procedure on the basis of the torsion tests at various forming conditions are presented and discussed. In the pipe-line grade steels, the combination of microalloying elements, accelerated cooling and transformation temperature, has led to much higher grain refinements and increased amount of bainitic ferrite microstructures than in the standard thermomechanical processing. Sensitivity analysis of studied microalloyed steel grades in the light of the discussed problems using microstructural analysis of obtained microstructures was also performed. Finally, the main challenges related to the multiscale modeling of proposed ideas are addressed.
Effect of Reheat Conditions on Microstructure Evolution and Precipitation Behavior in High Strength Linepipe Steel
Authors: Chastukhin Andrey V. , Ringinen Dmitry A. , Khadeev Grigory E. , Efron Leonid I.
Published: July 2013

The effects of slab reheat temperature and soaking time are studied to characterize austenite grain growth, microstructure homogeneity and dissolution of precipitates in linepipe X80 grade steel. It is shown that the uniformity of austenite microstructure strongly depends on the slab reheat temperature and soaking time. With increasing reheat temperature an abnormal growth of individual grains is observed that stems from gradual dissolution of microalloy carbonitrides. As the result, individual grain boundaries become unpinned and mobile thus "nucleating" secondary recrystallization. The highest reheat temperature at which the dissolution kinetics of precipitates is still slow enough to prevent the onset of secondary recrystallization within long soaking times is 1160°C. The as reheated austenite microstructure and the character of austenite grain size distribution are inherited throughout the entire roughing rolling sequence and even further downstream to the finishing rolling entry. The effects of reheat soaking time on shear fracture area and impact toughness are also described.
Effect of Different Cooling Paths on the Microstructure and Properties of a Plain Carbon Steel
Authors: Guo Jin , Hu Shui Ping , Mi Zhen Li , Zhang Dong Bin
Published: July 2013

The effect of different cooling paths on the microstructure and properties of a plain carbon steel was carefully investigated by thermal simulation, hot rolling, tensile tests and quantitative metallography. Experimental results indicate that the more rapid the cooling rate is, the smaller the average ferritic grain size is and the higher the mechanical properties are. Both ultra fast cooling method and ultra fast cooling+accelerated controlled cooling method could refine grain size and improve mechanical properties. Without any alloy addition, using the ultra fast cooling immediately after hot rolling process, the yield strength of the plain carbon steel could reach 360 MPa and the elongation is 32%.
A Fast Optimization Approach for Multi-Pass Wire Drawing Processes with a Penalty Fitness Function
Authors: Zhang Guang Liang , Wang Zhang Wei , Zhang Shi Hong
Published: July 2013

A fast optimization approach is demonstrated for design optimization of the multi-pass wire drawing process with the multi-objective genetic algorithm, and with the aims at minimizing both power consumption and temperature, via optimizing the process parameters involving pass number, pass schedule, die angle, bearing length and loops on capstan etc. A jump fitness function and a penalty fitness function are proposed for the survival of good designs and killing the bad designs which temperature, die wear factor, delta factor, or ratio of drawing stress to yield stress exceed the limits during optimization. The numerical examples show that the optimizer with the penalty fitness function, when its parameternranges from 1 to 2, presents the best performance in finding the minimum power consumption with a limit in temperature. Compared with a reference design, a significant reduction in the total power consumption about 300W, with the well control in temperature, delta factor and die life, has been achieved by the optimization. The penalty fitness function presents the better performance in the reduction of the iteration generations and computational cost to the jump fitness function.
Semi-Massive Nanocrystallised Composites: From the Process to Mechanical and Microstructural Investigations
Authors: Waltz Laurent , Retraint Delphine , Roos Arjen
Published: July 2013

The aim of the present study is first to describe an original process, the so called duplex process, whose feature is the coupling between the well-known SMAT (Surface Mechanical Attrition Treatment) and the traditional co-rolling. The first step of this process consists of SMA-Treatment of 316L stainless steel sheets to generate nanocrystalline layers on their top surfaces according to the grain refinement mechanism of austenitic steels which is well described in the literature. During the second step, three treated sheets are co-rolled at 550°C to obtain a semi-massive nanocrystallised multilayer structure with improved mechanical strength alternating nanocrystalline, transition and coarse grain layers.
The second part of this work deals with the mechanical and the microstructural characterization of the as-obtained structures. Thus, sharp nanoindentation tests performed over the cross section of the laminates coupled with Transmission Electron Microscopy (TEM) confirm the presence of nanograins after the thermomechanical treatment. In addition, the enhanced yield strength demonstrated by tensile tests correlate well with the theoretical volume fractions of nanoand transition layers. The interface cohesion between the sheets is tested by three-point bending tests and the interface bonding is evaluated by microstructural observations.
Microstructure and Reaction Mechanism of Multi-Laminated Ti-(SiCp/Al) Composites Subjected to Annealing at 1300°C
Authors: Pang Jin Cheng , Geng Lin , Fan G.H. , Li A.B. , Zhang Jie , Zheng Zhen Zhu , Cui X.P. , Wang Q.W.
Published: July 2013

The multi-laminated Ti-(SiCp/Al) composite was produced by hot press and subsequent hot roll bonding of Ti and SiCp/Al foils. The microstructure evolution of the composite in reaction annealing was investigated by scanning electron microscope (SEM) equipped with energy dispersive X-ray spectrometer (EDX) and X-ray diffractometer (XRD). The results show that after the reaction annealing at 1300°C for 3h, the Ti and SiCp/Al foils were completely consumed and transformed into the TiAl composite with a microlaminated structure. The microlaminated microstructure of the composite is composed of Ti3Al/(TiAl+Ti5Si3p)/Ti5Si3/duplex-phase (TiC+Ti3AlC) layers. The reaction mechanism is elucidated by employing the reaction model.
A Process Model for Electron Beam Welding with Variable Thickness
Authors: Huang Jiang Lin , Gebelin Jean Christophe , Turner Richard , Reed Roger C.
Published: July 2013

A process model for electron beam (EB) welding with a variable thickness weld joint has been developed. Based on theoretical aspects and experimental calibration of electron beam focusing, welding parameters including beam power, focus current, working distance and welding speed were formulated in the heat source model. The model has been applied for the simulation of assembly of components in a gas turbine engine compressor. A series of metallographic weld sections with different welding thickness were investigated to validate the predicted thermal results. The workpieces were scanned both prior to-and after welding, using automated optical metrology (GOM scanning) in order to measure the distortion induced in the welding process. The measured result was compared with predicted displacement. This work demonstrates the attempts to improve the EB welding process modelling by connecting the heat input directly from the actual welding parameters, which could potentially reduce (or even remove) the need for weld bead calibrations from experimental observation.
Flow Characteristics of Vacuum Assisted Resin Transfer Molding Process Depending on the Capillary Phenomenon
Authors: Kim Yun Hae , Lee Jin Woo , Park Jun Mu
Published: July 2013

Reducing the cost of composite material production is significant for expanding its usage and application in many ways, such as in the fields of aerospace, aviation, ocean industry and so on. To do this, It is important to minimize the production process of the material and to decrease the amount of scraps or any unnecessary particles. The Vacuum Assisted Resin Transfer Molding (VARTM) process, which is known for having many advantages, has become recognized as one of the most low-cost manufacturing model. VARTM process can be divided into three main steps: performing, resin filling and hardening steps. The most important step among all these three steps is the Resin Filling stage, a process when resin is impregnated into the mat. Mostly, Resin Filling stage is greatly affected by the level of permeability, a characteristic of stiffener due to pneumatic resistant nature in the process. Other factors such as viscosity, technological vacuuming, or even stiffening process itself could also influence the production as well. During Resin Filling stage, Resin tends to spread out in the center first because of capillary phenomenon. In this research, the researchers examined the mechanical property and the pneumatic nature of Resin by dividing the pneumatic movement of the Resin into sections. Based on this result, the researchers found the correlations between the capillary phenomenon and Resin impregnation, and analyzed the movement mechanism in Resin filling stage.
Novel Physical Simulation Technique Development for Multistage Metal Plastic Deformation Processing
Authors: Naumov Anton A. , Bezobrazov Yuriy A. , Kolbasnikov Nicolay G. , Chernikov Evgenii V.
Published: July 2013

There are numbers of metal plastic deformation processes such as multistage hot rolling, rotational forging etc. where huge amount of strain is reached. To provide physical simulation of these processes, new tension-compression technique for Gleeble Systems was developed. All standard methods used in physical simulation with the help of Gleeble are described and compared with new technique. Several experiments are made and described in present work to show the difference between standard and developed techniques.
Optimization of Tilt-Casting of Aluminum Alloy Automobile Drain Pipes through Numerical Simulation
Authors: Wang Ye , Wu Shi Ping , Xue Xiang , Guo Jing Jie
Published: July 2013

The effect of major parameters, such as pouring temperature, tilt time and preheating temperature of mold, on the tilt casting of aluminum alloy automobile drain pipes is studied through numerical simulation using single factor and orthogonal test methods. The simulation results of single factor test indicate that the increase in the pouring temperature and mold preheating temperature could effectively reduce the shrinkage tendency and the shortage of tilt time would cause lower temperature gradient of casting at the beginning of solidification, thus would lead the extension of solidification time. And the results of orthogonal test showed that the sequence of factors having effect on the filling and solidification process, are pouring temperature, tilt time and preheating temperature of mold. Finally, combined the result of single factor test with orthogonal test, an optimized tilt-casting process was proposed by investigating the velocity distribution at each stage of the filling process and the isolated area distribution of liquid phase in the solidification process, and by predicting the position of porosity in the casting. The effectiveness of the proposed process parameters in producing high quality castings is also proved through numerical simulation.
The Development of Interphase Precipitated Nanometre-Sized Carbides in the Advanced Low-Alloy Steels
Authors: Yang Jer Ren , Yen H.W. , Chen C.Y. , Huang C.Y.
Published: July 2013

In this work, the investigation of transmission electron microscopy has elucidated the morphologies of the interphase precipitated carbides in an experimental Ti-Mo-bearing steel into three types: (1) planar interphase precipitation with regular sheet spacing (designated as PIP), (2) curved interphase precipitation with regular sheet spacing (designated as Regular CIP), and (3) curved interphase precipitation with irregular sheet spacing (designated as Irregular CIP). The planar sheets of carbides have also been analyzed and found to be oriented close to ferrite planes {211}, {210} and {111}; the results of transmission electron microscopy provide strong evidence to suggest that the development of interphase-precipitated carbides can be associated with the growth of incoherent ferrite/austenite interface by the ledge mechanism. The sheet spacing and inter-carbide spacing in the sheet have been measured and estimated in this work. The sheet spacing is found to be finer than the inter-carbide spacing in the sheet for all samples investigated. The result reflects that the distribution of interphase-precipitated carbides is anisotropic and cannot be considered random distribution. The relevance of the Orowan mechanism to the non-random distribution of interphase-precipitated carbides has been considered. The contribution of the dispersion of interphase-precipitated carbides to the yield strength of the steel studied has been estimated. It is revealed that an optimum component about 400 MPa contributed by interphase-precipitated carbides can be achieved, and the finding is consistent with the hardness data. Other examples of the different alloy steels are also addressed.
Influence of Rotation on Dynamic Stall
Authors: Gardner A. D. , Richter K.
Published: June 2013

A computational investigation of the effect of rotation on two-dimensional (2D) deep dynamic stall has been undertaken, showing that the effect of rotation is to reduce the severity of the pitching moment peak and cause earlier reattachment of the flow. A generic single blade rotor
geometry was investigated, which had a pitching oscillation around the quarter-chord axis while in hover, causing angle-driven dynamic stall. The results at the midpoint of the blade have the same Mach number (0.31), Reynolds number (1.15 × 106), and pitching motion (α
= 13° ± 7°) as a dynamic stall test case for which significant experimental wind tunnel data and 2D computations exist. The rotating blade is compared with 2D computations and computations using the same blade without rotation at Mach 0.31 and with the same pitching motion.
All test cases involve geometries propagating into undisturbed flow with no downwash. The three-dimensional (3D) grid computed without rotation had lower lift at the reference section than for a 2D computation with the same geometric angle of attack time history, and the lift overshoot classically
observed for Spalart–Allmaras turbulence models during 2D dynamic stall was significantly reduced in the 3D case. Rotation reduced the strength of the dynamic stall vortex, which reduced the accompanying pitching moment peak by 25%.
Effects of Hot Spots Policing on Crime
Authors: Braga Anthony A.
Published: July 2013

This Campbell systematic review synthesizes the existing published and non‐published empirical evidence on the effects of focused police crime prevention interventions at high‐activity crime places and will provide a systematic assessment of the preventive value of focused police crime prevention efforts at crime hot spots. The review also examined whether focused police actions at specific locations result in crime displacement.

Studies that used randomized controlled experimental or quasi‐experimental designs were selected. Nine eligible studies were included in this review.

The results of this systematic review support the assertion that focusing police efforts at high activity crime places can be effective in preventing crime. Whatever the impact, we need to know more about the effects of hot spots policing approaches on the communities that the police serve.
Atrial Fibrillation Is Poorly Tolerated by Patients with Hypertrophic Concentric Cardiomyopathy Caused by Mitochondrial tRNALeu (UUR) Mutations
Authors: Heliö Tiina , Götz Alexandra , Rapola Janne , Kiuru-Enari Sari , Kivistö Sari , Heikinheimo Terttu , Suomalainen Anu
Published: June 2013

Knowledge on the molecular background of mitochondrial disorders has accumulated during the past two decades, but clinical and molecular features of mitochondrial cardiomyopathies (CMPs) are only starting to be characterized. We studied the detailed cardiologic phenotype of patients with adult-onset CMPs associated with mitochondrial DNA (mtDNA) mutations and their relatives, from three families. We identified a pathogenic T3258C point mutation of mtDNA tRNALeu(UUR) in an adult patient with mitochondrial myopathy and CMP, with acute manifestation of dyspnea and elevated plasma N-terminal pro-B-type natriuretic peptide concentration. Two other families with maternally segregated CMP, fatal in three patients, had the A3243G mutation in tRNALeu(UUR) of mtDNA. Many of the mutation carriers, even if oligosymptomatic, had concentric, non-obstructive hypertrophic CMP with diastolic dysfunction or restrictive hemodynamics, or depression of systolic function especially at times when patients had lactic acidosis. Atrial fibrillation led to manifest heart failure in four patients, fatal in one. In conclusion, tRNALeu(UUR) mutations in mtDNA may underlie mitochondrial non-obstructive, sometimes fatal, hypertrophic CMPs of adult age. Such CMPs are characterized by left ventricular hypertrophy and poor tolerance of atrial arrhythmias, often leading to rapidly deteriorating systolic function and heart failure. These patients benefit of rapid intervention of tachyarrhythmias. These patients may not have neurological symptoms, and may therefore remain underdiagnosed. Our observations emphasize that patients with tRNALeu(UUR) mutations need cardiologic evaluation and follow- up. tRNALeu(UUR) mutations should be screened of patients with hypertrophic CMP and metabolic acidosis, especially if atrial arrhythmia provoked cardiac decompensation.