bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photonics Research and Development Perspectives in Poland
Authors: Woliński Tomasz R. , Domański Andrzej W. 
Published: December 2012

AbstractPhotonics is one of the most promising and fastest developing innovative technologies and a key‐enabling technology of Europe. Poland has a long tradition in optics and photonics research, especially in laser‐based and optical fiber technologies. This article will describe current research activities in the field of photonics as well as presenting selected development perspectives occurring in this area in recent years in Poland.
Novel Applications of Ultra‐short Pulsed Lasers
Authors: Peters Rigo , Oldorf Paul 
Published: December 2012

AbstractDue to their outstanding properties ultra‐short pulsed lasers (USP) have recently gained strong interest in laser material processing. While first applications of this laser type have been mainly found in mass production like photovoltaics or cutting of hardened glass for display panels, nowadays, a broad range of diverse applications is emerging, making USP‐lasers one of the fastest growing fields in laser technology.
Plasma Meets Glass
Authors: Gerhard Christoph , Viöl Wolfgang , Kretschmer Marcus 
Published: December 2012

AbstractDue to its particular optical and mechanical properties, fused silica is one of the most relevant materials for the production of optical, opto‐mechanical and opto‐electrical components and systems. Since such glasses feature a high transmittance in the ultraviolet (UV) spectral range, deep UV‐laser irradiation or several hybrid methods are usually applied in laser‐based manufacturing of optically operative micro‐structures on fused silica substrates. Against this background, the development of novel methods for increasing the UV‐absorption temporarily is of great interest for laser scribing of optical gratings, micro optics and integrated optical systems. Here, cost‐ and energy‐efficient plasma treatment techniques at atmospheric pressure offer different approaches that can also be applied to other optical glasses.
Optical Fiber Applicators for Fluorescence Measurements
Authors: Cappius Hans‐Joachim , Schmitt Franz‐Josef , Südmeyer Heinrich 
Published: December 2012

AbstractFor health protection and reproducible process outcome in chemical engineering clean surfaces are necessary. Optical methods and special applicators can enable cleaning validation in areas to date not as accessible as desired, e.g. in tubes. Here, design concepts for fiberbased fluorescence and Raman detection in long thin lumina and the lower detection limits of protein coatings are presented. The main aspect of this type of fiber applicators is the maximization of light transmitted to and collected from the illuminated spot. This is achieved by a patented manufacturing method of melting the fiber tip and grinding and polishing the ball‐lens formed at the fiber tip to deflect the light from the fiber core towards one side.
Components and Tools for Polarization‐maintaining Fiber Optics
Authors: Krischke Anja , Knothe Christian , Oechsner Ulrich , Lamott André 
Published: December 2012

AbstractFiber cables open up new vistas for the design of modular devices and compact setups for industrial and scientific applications. Special fibers, such as polarization‐maintaining singlemode fibers, are predestined for use in complex, selfcontained setups, increasing laser safety by reducing the laser safety classification. Most importantly, a sensitive and delicate measurement system can still enjoy the benefits of a laser beam, with the desirable features of polarization state and coherence, but be physically separated from the laser source. The measurement setup and the laser source are decoupled mechanically and thermally in order to avoid any mutual negative impacts.
AlGaN layer structures for deep UV emitters on laterally overgrown AlN/sapphire templates
Authors: Knauer A. , Kueller V. , Zeimer U. , Weyers M. , Reich C. , Kneissl M. 
Published: December 2012

AbstractThe crystalline perfection of n‐type AlxGa1 − xN layers with Al content higher than x > 0.4 on epitaxial laterally overgrown AlN was investigated by high resolution X‐ray diffraction, photoluminescence (PL), cathodoluminescence (CL) and resistivity mapping. The critical layer thickness of AlGaN is drastically increased compared to planar AlN/sapphire templates. CL mapping reveals compositional variations caused by different Ga incorporation during growth over steps resulting from step bunching of the AlN. With increasing Al content the homogeneity is improved. N‐type conductivity was achieved for AlGaN with Al content of up to 82%. Temperature dependent PL measurements of AlGaN/AlN multi quantum wells (MQW) emitting at 230 nm show that the internal quantum efficiency improves by a factor of about two for MQWs on defect reduced laterally overgrown AlN compared to planar AlN/sapphire templates. The data show the usefulness of defect reduced AlN templates as quasi‐substrates for AlGaN layer structures with high Al content that can be employed in light emitting diodes emitting in the deep ultraviolet.
Measuring methods for the investigation of in‐plane and cross‐plane thermal conductivity of thin films
Authors: Völklein F. , Reith H. , Meier A. 
Published: December 2012

AbstractThe characterization of the thermal properties of thin film materials is important both for understanding of their structure and conduction mechanisms and for their technical applications. Thermal conductivity and diffusivity are crucial parameters for the design of integrated devices, thermal microsensors and actuators. Reliable system simulation and design optimization of such devices is based on the accurate determination of thermophysical properties. It is therefore highly desirable to acquire such data. Usually, thermal properties of thin films differ considerably from the bulk values, since the parasitic surface effects are much stronger due to the smaller dimensions and aspect ratios. The measurement of these properties is sophisticated and associated with various problems. We report on steady‐state and transient methods for the characterization of in‐plane and cross‐plane film properties by using microelectrothermal chips.
Synthesis and characterization of poly(vinylidene‐trifluoroethylene)/NiTiO2
Authors: Kuang Xiwen , Lin Shuang , Zhu Hong 
Published: December 2012

AbstractNiTiO2 nanoparticles were prepared by the sol–gel method, and a composite film of poly(vinylidene‐trifluoroethylene) (PVDF‐TrFE)/NiTiO2 was prepared by the solution cast method. The microstructure of NiTiO2 was investigated by transmission electron microscopy (TEM). The film was characterized by TEM, X‐ray diffraction (XRD), differential scanning calorimetry (DSC), and dielectric property testing. The results showed that the NiTiO2 nanoparticles were well dispersed in the polymer matrix. With the increase of NiTiO2 content, the crystallinity of PVDF‐TrFE/NiTiO2 decreased. The permittivity of the films improved significantly with the increase of NiTiO2 content. The permittivity at 1000 Hz and room temperature increased to 18.56 for PVDF‐TrFE/Ni0.1TiO2 (60 wt%) from the value of 11.17 for the pure PVDF‐TrFE film. Furthermore, the permittivity of the composite film increased with the increase of temperature.
Symmetry breaking and low energy conformational fluctuations in amorphous graphene
Authors: Li Y. , Drabold D. A. 
Published: December 2012

Abstractmagnified imageRecently, the prospects for amorphous phases of graphene (α‐g) have been explored computationally. Initial models were flat, and contained odd‐member rings, while maintaining threefold coordination and sp2 bonding. Upon relaxation, puckering occurs, and may be traced to the existence of pentagons, in analogy with the situation for fullerenes. In this work, we systematically explore the inherent structures with energy close to the flat starting structure. As expected, the planar symmetry can be broken in various ways, which we characterize for 800‐atom model of α‐g, always using local basis density functional techniques. The classical normal modes of various structural models are discussed, with an emphasis on imaginary modes indicating the evolution from flat to puckered. We also discuss very low energy conformational fluctuations akin to those seen previously in amorphous silicon, and reflect on the nature of the amorphous “ground state” within a network of fixed topology. For completeness, high energy modes were also computed, and are found to be associated with strained parts of the network.
Sodium molecule on the surface of liquid helium‐4 droplets: optical transitions probe collective excitations
Authors: Tehver Imbi , Hizhnyakov Vladimir , Benedek Giorgio 
Published: December 2012

AbstractAlkali molecules trapped at the surface of a liquid helium‐4 droplets offer a unique tool to explore their surface excitations. An optical transition between the triplet states in a sodium dimer leads to a contraction of the molecule and a conversion of the helium‐droplet collective excitations localized around the sodium dimer into much softer, delocalized excitations of the liquid droplet surface similar to tidal waves. The localized phonon zero‐point energy released in this process yields a peculiar asymmetric triangular shape of the surface‐phonon sideband of the molecular vibronic lines, with the suppression of the zero‐phonon line. An optical transition between the singlet states of a sodium molecule changes the forces between the molecule and the neighbor helium‐4 atoms. As a result, the singlet‐singlet transition in a sodium molecule leads, in addition to the zero‐phonon transition, to transitions accompanied by the excitation of bulk phonons of the quantum liquid droplet and its surface phonons. In the low‐frequency limit surface phonons contribute more strongly to the vibration of the neighbor helium‐4 atoms than bulk phonons. This results in a dominant contribution of surface phonons in the low‐energy wing of the zero‐phonon line in the spectrum. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence and scintillation mechanism in Ce3+ and Pr3+ doped (Lu,Y,Gd)3(Ga,Al)5O12 single crystal scintillators
Authors: Nikl M. , Kamada K. , Kurosawa S. , Yokota Y. , Yoshikawa A. , Pejchal J. , Babin V. 
Published: December 2012

AbstractLuminescence processes occurring in the 5d1 excited state of Ce3+ and Pr3+ centers in the (Gd,RE)3(Ga,Al)5O12, RE=Lu,Y, multicomponent garnet host were studied by purely optical contactless methods. Combination of measurements of the prompt nanosecond decay and slow delayed radiative recombination decay allows to resolve the presence of thermal quenching and thermally induced ionization processes acting upon the 5d1 excited state. Additional energy transfer process depleting the 5d1 state of Pr3+ center was found and is due to the resonance of 5d1‐3H4 emission transition of Pr3+ and 8S‐6Px absorption transition of Gd3+ which might be responsible for noticeably lower light yield in Pr‐doped multicomponent garnets. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hall effect of tetragonal and orthorhombic SrRuO3 films
Authors: Bern Francis , Ziese Michael , Dörr Kathrin , Herklotz Andreas , Vrejoiu Ionela 
Published: December 2012

AbstractHigh quality orthorhombic and tetragonal SrRuO3 thin films were grown by pulsed laser deposition on SrTiO3(001) and Ba0.75Sr0.25TiO3 buffered LaAlO3(001) substrates. Resistivity vs. temperature curves showed a slope change at a Curie temperature of 147.5 ± 2 K for 40 nm thick films irrespective of crystalline symmetry. The Hall resistivity of both films contained an anomalous Hall contribution. The anomalous Hall coefficient was positive throughout the whole temperature range for the tetragonal film, whereas it showed a sign change at 143 K for the orthorhombic film. This is a strong indication that the Berry‐phase mechanism is the dominant anomalous Hall effect mechanism in SrRuO3. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Supporting students’ progression in science: Continuity between the particular, the contingent, and the general
Authors: HAMZA, KARIM M. , WICKMAN PER‐OLOF 
Published: December 2012

ABSTRACTIn this paper, we analyze the relation between particular, contingent, and general aspects of a school science activity and show how they are intertwined in nontrivial ways as students give explanations for how a real galvanic cell works during conversations with a researcher. The conversations were examined by using practical epistemology analysis, which made it possible to follow students’ meaning making in detail. The analysis revealed interactions between generic explanations of electrochemistry and the distinctions and correlations that were connected to particulars and contingencies of the galvanic cell. Consequences of these interactions amounted to becoming reminded of knowledge one had come across before, being able to connect distinctions of particular features of the cell to generalized chemical explanations, and realizing which aspects may be excluded from the account. The results indicate that learning in science needs to be approached more as a contingent process than as something that progresses along one particular dimension. They show how students appropriate the sociocultural tools of science and how they situate what they learn in both the particular features of the activity and in the relevant science. Hence, there is a need for more inclusive accounts of how students progress toward increased competency in science.
How students blend conceptual and formal mathematical reasoning in solving physics problems
Authors: KUO ERIC , HULL MICHAEL M. , GUPTA AYUSH , ELBY ANDREW 
Published: December 2012

ABSTRACTCurrent conceptions of quantitative problem‐solving expertise in physics incorporate conceptual reasoning in two ways: for selecting relevant equations (before manipulating them) and for checking whether a given quantitative solution is reasonable (after manipulating the equations). We make the case that problem‐solving expertise should include opportunistically blending of conceptual and formal mathematical reasoning even while manipulating equations. We present analysis of interviews with two students, Alex and Pat. Interviewed students were asked to explain a particular equation and solve a problem using that equation. Alex used and described the equation as a computational tool. By contrast, Pat found a shortcut to solve the problem. His shortcut blended mathematical operations with conceptual reasoning about physical processes, reflecting a view—expressed earlier in his explanation of the equation—that equations can express an overarching conceptual meaning. Using case studies of Alex and Pat, we argue that this opportunistic blending of conceptual and formal mathematical reasoning (i) is a part of problem‐solving expertise, (ii) can be described in terms of cognitive elements called symbolic forms (Sherin, 2001), and (iii) is a feasible instructional target.
A new intrusion detection method based on SVM with minimum within‐class scatter
Authors: An Wenjuan , Liang Mangui 
Published: December 2012

ABSTRACTIntrusion detection has become an indispensable technique to ensure the security and reliability of information systems. Support vector machine (SVM) and its many improved algorithms have been successfully applied to intrusion detection systems in recent years. However, the training process of SVM ignores an important prior knowledge, the within‐class structure in the training set. In this paper, we propose an improved classification algorithm, which combines minimum within‐class scatter in Fisher discriminant analysis with traditional SVM. The central idea is to find an optimal separating hyperplane such that the margin is maximized, whereas the within‐class scatter is kept as small as possible. This new algorithm is called SVM with minimum within‐class scatter (WCS‐SVM). A set of experiments is conducted on ten benchmarking datasets and KDDCUP'99 experimental data of MIT Lincoln Laboratory to test the generalization performance of the WCS‐SVM algorithm. Experimental results show that the WCS‐SVM algorithm has better discriminatory power than traditional SVM and kernel Fisher discriminant analysis and it has higher true detection rate and lower false positive rate for intrusion detection systems. Copyright © 2012 John Wiley & Sons, Ltd.
Wireless security: securing mobile UMTS communications from interoperation of GSM
Authors: Southern Eric , Ouda Abdelkader , Shami Abdallah 
Published: December 2012

ABSTRACTWireless communications have revolutionized the way the world communicates. An important process used to secure that communication is authentication. As flaws in the security of a wireless network are discovered, new protocols and algorithms are required to meet those security issues. When creating new algorithms and systems, it is possible that the existing equipment may not be able to implement the new protocols, which means that integration may be required to transition from an old security protocol to the new more secure protocol. Stationary wireless networks were created without a strong need to integrate protocols and have simply developed slightly more secure protocols to protect old equipment. New protocols in stationary wireless networks are implemented without integration as a requirement. Mobile wireless networks have the requirement of allowing old equipment to use the entire network as it is advantageous to allow new mobile equipment to connect to old networking equipment to increase coverage areas and for old equipment to connect to new towers for roaming and billing. This requirement for mobile networks means that integration is required. There are flaws in this integration of Global System for Mobile Communications (GSM) into Universal Mobile Telecommunications System (UMTS) networks. Those flaws are analyzed, and two practical solutions are proposed. Copyright © 2012 John Wiley & Sons, Ltd.
Physicochemical and Biological Properties of Biomimetic Mineralo‐Protein Nanoparticles Formed Spontaneously in Biological Fluids
Authors: Peng Hsin‐Hsin , Wu Cheng‐Yeu , Young David , Martel Jan , Young Andrew , Ojcius David M. , Lee Yu‐Hsiu , Young John D. 
Published: December 2012

AbstractRecent studies indicate that mineral nanoparticles (NPs) form spontaneously in human body fluids. These biological NPs represent mineral precursors that are associated with ectopic calcifications seen in various human diseases. However, the parameters that control the formation of mineral NPs and their possible effects on human cells remain poorly understood. Here a nanomaterial approach to study the formation of biomimetic calcium phosphate NPs comparable to their physiological counterparts is described. Particle sizing using dynamic light scattering reveals that serum and ion concentrations within the physiological range yield NPs below 100 nm in diameter. While the particles are phagocytosed by macrophages in a size‐independent manner, only large particles or NP aggregates in the micrometer range induce cellular responses that include production of mitochondrial reactive oxygen species, caspase‐1 activation, and secretion of interleukin‐1β (IL‐1β). A comprehensive proteomic analysis reveals that the particle‐bound proteins are similar in terms of their identity and number, regardless of particle size, suggesting that protein adsorption is independent of particle size and curvature. In conclusion, the conditions underlying the formation of mineralo‐protein particles are similar to the ones that form in vivo. While mineral NPs do not activate immune cells, they may become pro‐inflammatory and contribute to pathological processes once they aggregate and form larger mineral particles.
Using Standards to Develop Student Learning Outcomes
Authors: Komives Susan R. , Smedick William 
Published: December 2012

AbstractThis chapter asserts that leadership programs based on quality standards of practice should lead to strong student outcomes. The chapter explores applications of The Council for the Advancement of Standards (CAS), National Association of Campus Activities (NACA), and the International Leadership Association (ILA) Guiding Questions. ILA Outcomes and Assessment Guiding Question: “What are the intended outcomes of the leadership education program and how are they assessed and used to ensure continuous quality improvement?”
Exploring Local to Global Leadership Education Assessment
Authors: Dugan John P. 
Published: December 2012

AbstractFrom individual student learning outcomes to full‐scale program enhancement, assessment is critical in developing and sustaining leadership education. This chapter will look at assessment techniques and trends spanning from local to global frameworks. International Leadership Association overarching Outcomes and Assessment Guiding Question: “What are the intended outcomes of the leadership education program and how are they assessed and used to ensure continuous quality improvement?”
An Assessment of the Hospital Disease Burden and the Facilities for the In‐hospital Care of Trauma in KwaZulu‐Natal, South Africa
Authors: Hardcastle Timothy C. , Samuels Candice , Muckart David J. 
Published: December 2012

AbstractBackgroundTrauma is a significant cause of morbidity and mortality in South Africa. The present study was designed to review the hospital trauma disease burden in light of the facilities available for the care of the injured in KwaZulu‐Natal (KZN), South Africa’s most populous province.The primary outcomes were the annual hospital burden of trauma in KZN, determined through data extrapolation, and evaluation of the data in light of available hospital facilities within the province of KZN, a developing province. The data were obtained through review of the trauma load in relation to all emergency cases at all levels of hospitals.MethodsHospital administrators in KZN were requested to submit trauma caseloads for the months of March and September 2010. Caseloads were reviewed to determine the trauma load for the province per category using two extrapolation methods to determine the predicted range of annual incidence of trauma, intentional versus non‐intentional trauma ratios and population‐related incidence of trauma. The results were GIS mapped to demonstrate variations across districts. Hospital data were obtained from assessments of structure, process, and personnel undertaken prior to a major sporting event. These were compared to the ideal facilities required for accreditation of trauma care facilities of the Trauma Society of South Africa and other established documents.ResultsData were obtained from 36 of the 47 public hospitals in KZN that manage acute emergency cases. The predicted annual trauma incidence in KZN ranges from 124,000 to 125,000, or 12.9 per 1,000 population. This would imply a national public hospital trauma load on the order of at least 750,000 cases per year. Most hospitals are required to treat trauma; however, within KZN many hospitals do not have adequate personnel, medical equipment, or structural integrity to be formally accredited as trauma care facilities in terms of existing criteria.ConclusionsThere is a significant trauma load that consumes vital emergency center resources. Most hospitals will need extensive upgrading to provide appropriate care for trauma. An inclusive trauma system needs to be formalized and funded, especially in light of the planned National Health Insurance for South Africa