bluuebunny/crossref_metadata_2025 huggingface dataset:
Opportunistic Frame Forwarding in Wireless Mesh Networks
Authors: Liang Shih Tsung , Song Bo Yi , Su Yu Yao
Published: May 2015

Opportunistic routing has been shown to achieve the high throughput of the wireless mesh network with lossy channels. Different from deterministic routing mechanisms in which a frame is transmitted and forwarded along with a fixed and predetermined path, the opportunistic routing technique allows multiple nodes hearing the frame to form the forwarder set containing promising candidates for the frame forwarding. Existing opportunistic routing protocols typically choose among forwarding candidates based on the decision made from the transmitter disregarding the current loads in candidates. In this paper, the opportunistic frame forwarding mechanism with considering backlog of frames among forwarders is proposed and analyzed. Specifically, in addition to take into account the delivery probability, our proposal restricts members of the forwarder set for a given transmitter to those wireless nodes whose transmission range covers one another and makes the true forwarder picked from the forward set of a given transmitting frame being the one who gains access to wireless channel for the frame before others do. Therefore, the efficient and load-balanced opportunistic routing for wireless mesh networks can be achieved. Analytic results show that the proposed method compared to the deterministic routing methodology can achieve the high frame delivery ratio.
Secure Data Synchronization over a Mobile Peer-to-Peer Network
Authors: Ke Chih Kun , Lin Zheng Hua
Published: May 2015

In previous work, we have proposed a service mechanism which automatically syncs the file resources among discrete mobile devices. The mechanism includes four modules. The role-based access control module (RBAC) defined an organization policy which constructs some rules for file resources accessing. The user identification module dispatches a user some specific role (s) with relevant permission (s) and constraint (s) to access organization file resources. The en-capsulation/de-capsulation module enforces the JXTA protocol to sync the file resource synchronization over a mobile peer-to-peer network. The knowledge base module stores various organization file resources in the proposed service mechanism. However, the service mechanism faces an important challenge about data security. How to securely sync organization file resources among discrete mobile devices is worth exploring. In this study, we enforces some cryptographic techniques, including advanced encryption standard (AES), Triple data encryption standards (Triple-DES), and data encryption standards (DES), to examine secure synchronization of organization file resources among discrete mobile devices. The experiment results show the proposed mechanism is secure to automatically sync file resources among discrete mobile devices. The contribution of this work is to solve data security issue in syncing organization file resources among discrete mobile devices. We also strengthen an organization mobility to acquire the file resources by a mobile device in anywhere.
Three-Dimensional Object Encoding Approach Using Computer-Generated Integral Imaging and Random Phase Encoding
Authors: Li Xiao Wei , Cho Arum Sulgi , Lee In Kwon , Cho Sung Jin , Kim Seok Tae
Published: May 2015

In this paper, we propose a three-dimensional (3D) image encryption method using the computer-generated integral imaging and random phase mask encoding. The advantages of this proposed method can not only increase the resolution of the reconstructed plane images, but also greatly improve the robustness compared with conventional methods. We present the experimental results to verify the performance of our proposed encryption method.
Dual-Specificity Phosphatase 1 and Tristetraprolin Cooperate To Regulate Macrophage Responses to Lipopolysaccharide
Authors: Smallie Tim , Ross Ewan A. , Ammit Alaina J. , Cunliffe Helen E. , Tang Tina , Rosner Dalya R. , Ridley Michael L. , Buckley Christopher D. , Saklatvala Jeremy , Dean Jonathan L. , Clark Andrew R.
Published: May 2015

Dual-specificity phosphatase (DUSP) 1 dephosphorylates and inactivates members of the MAPK superfamily, in particular, JNKs, p38α, and p38β MAPKs. It functions as an essential negative regulator of innate immune responses, hence disruption of the Dusp1 gene renders mice extremely sensitive to a wide variety of experimental inflammatory challenges. The principal mechanisms behind the overexpression of inflammatory mediators by Dusp1−/− cells are not known. In this study, we use a genetic approach to identify an important mechanism of action of DUSP1, involving the modulation of the activity of the mRNA-destabilizing protein tristetraprolin. This mechanism is key to the control of essential early mediators of inflammation, TNF, CXCL1, and CXCL2, as well as the anti-inflammatory cytokine IL-10. The same mechanism also contributes to the regulation of a large number of transcripts induced by treatment of macrophages with LPS. These findings demonstrate that modulation of the phosphorylation status of tristetraprolin is an important physiological mechanism by which innate immune responses can be controlled.
Photosensitizer and Light Pave the Way for Cytosolic Targeting and Generation of Cytosolic CD8 T Cells Using PLGA Vaccine Particles
Authors: Bruno Cristina , Waeckerle-Men Ying , Håkerud Monika , Kündig Thomas M. , Gander Bruno , Johansen Pål
Published: May 2015

The generation of CTLs is crucial in the immunological fight against cancer and many infectious diseases. To achieve this, vaccine Ags need to be targeted to the cytosol of dendritic cells, which can activate CD8 T cells via MHC class I (MHCI). Therefore, such targeting has become one of the major objectives of vaccine research. In this study, we aimed to bypass the unwanted and default MHC class II Ag presentation and trigger MHCI presentation by using a photosensitizer that, upon light activation, would facilitate cytosolic targeting of codelivered Ag. Poly(lactide-co-glycolide) microparticles ∼1 μm size were loaded with OVA and the photosensitizer tetraphenyl chlorine disulphonate (TPCS2a) and administered intradermally in mice, which were illuminated 1 d later for activation of the photosensitizer. Immunization in the presence of TPCS2a significantly increased activation of CD8 T cells compared with immunization without TPCS2a and as measured by CD8 T cell proliferation, production of proinflammatory IFN-γ, TNF-α, and IL-2, and prevention of tumor growth. Cytotoxicity was demonstrated by granzyme B production in vitro and by in vivo killing of CFSE-labeled targets. CD4-dependent Ab responses were abrogated in mice immunized with TPCS2a-containing particles, suggesting that photosensitization facilitated a shift from default MHC class II toward MHCI Ag presentation. Hence, vaccine particles with Ag and photosensitizers proved an effective vehicle or adjuvant for stimulation of CTLs, and they may find potential application in therapeutic cancer vaccination and in prophylactic and therapeutic vaccination against intracellular infections.
Modelling social vulnerability in sub-Saharan West Africa using a geographical information system
Authors: Lawal Olanrewaju , Arokoyu Samuel B.
Published: May 2015

In recent times, disasters and risk management have gained significant attention, especially with increasing awareness of the risks and increasing impact of natural and other hazards especially in the developing world. Vulnerability, the potential for loss of life or property from disaster, has biophysical or social dimensions. Social vulnerability relates to societal attributes which has negative impacts on disaster outcomes. This study sought to develop a spatially explicit index of social vulnerability, thus addressing the dearth of research in this area in sub-Saharan Africa. Nineteen variables were identified covering various aspects. Descriptive analysis of these variables revealed high heterogeneity across the South West region of Nigeria for both the state and the local government areas (LGAs). Feature identification using correlation analysis identified six important variables. Factor analysis identified two dimensions, namely accessibility and socioeconomic conditions, from this subset. A social vulnerability index (SoVI) showed that Ondo and Ekiti have more vulnerable LGAs than other states in the region. About 50% of the LGAs in Osun and Ogun have a relatively low social vulnerability. Distribution of the SoVI shows that there are great differences within states as well as across regions. Scores of population density, disability and poverty have a high margin of error in relation to mean state scores. The study showed that with a geographical information system there are opportunities to model social vulnerability and monitor its evolution and dynamics across the continent.
Beyond traditional dairy veterinary services: ‘It’s not just about the cows!’
Authors: Van der Leek Martin L.
Published: May 2015

It remains a challenge for the role of the dairy veterinarian to move beyond that traditionally held. In larger herds with a high reproductive workload, we are at great risk of becoming specialist technicians. Instead we seek greater involvement, to deliver comprehensive services and to be recognised for them, personally and financially. Given the frequency of our visits, knowledge and analytical skills we are in a unique position to provide inputs that complement advice given by other consultants. Failure to do so has economic consequences for both veterinarian and dairyman. The opportunity for and value of inputs will differ for every client, and we need to remain cognizant of their motivation. This review article shares perspectives, opportunities and tools that might enable moving beyond the traditional role. It starts with a review of available research describing the dynamic between dairyman and veterinarian and how this might impact an animal health production management programme. A description of the experiences of others follows, interspersed by the personal experiences of the author, working with large total mixed ration-fed herds in the United States of America. The following attributes and roles can be associated with a significant economic impact: gatekeeper; conduit; executor; verifier; monitor; facilitator and mediator; trainer, motivator and coach; applied nutritionist; technologist; champion of animal welfare, food safety and judicious antibiotic use; and confidant. Each is elucidated and described in context, revealing a need for continuing education. The nature of the relationship between veterinarian and client will determine the opportunity for and value of each. The veterinarian is in a unique position to become an integral part of the management team and to be fairly compensated as such. The onus rests on the veterinarian to broaden his/her knowledge and skills and to demonstrate their value.
Medical education and the quality improvement spiral: A case study from Mpumalanga, South Africa
Authors: Bac Martin , Bergh Anne-Marie , Etsane Mama E. , Hugo Jannie
Published: May 2015

Background: The short timeframe of medical students’ rotations is not always conducive to successful, in-depth quality-improvement projects requiring a more longitudinal approach.Aim: To describe the process of inducting students into a longitudinal quality-improvement project,using the topic of the Mother- and Baby-Friendly Initiative as a case study; and to explore the possible contribution of a quality-improvement project to the development of student competencies.Setting: Mpumalanga clinical learning centres, where University of Pretoria medical students did their district health rotations.Method: Consecutive student groups had to engage with a hospital’s compliance with specific steps of the Ten Steps to Successful Breastfeeding that form the standards for the Mother- and Baby-Friendly Initiative. Primary data sources included an on-site PowerPoint group presentation (n = 42), a written group report (n = 42) and notes of individual interviews in an end-of-rotation objectively structured clinical examination station (n = 139).Results: Activities in each rotation varied according to the needs identified through the application of the quality-improvement cycle in consultation with the local health team. The development of student competencies is described according to the roles of a medical expert in the CanMEDS framework: collaborator, health advocate, scholar, communicator, manager and professional. The exposure to the real-life situation in South African public hospitals had a great influence on many students, who also acted as catalysts for transforming practice.Conclusion: Service learning and quality-improvement projects can be successfully integrated in one rotation and can contribute to the development of the different roles of a medical expert. More studies could provide insight into the potential of this approach in transforming institutions and student learning.
The Catechetical School in Alexandria
Authors: Oliver Willem H.
Published: May 2015

During her Golden Era, Alexandria, the Delta City of Egypt, was the pride of Africa in that she was larger than the two other world cities of the Roman Empire � Rome and Antioch � and also the unrivalled intellectual centre of the (Greco-)Roman world. Her schools, including the Didaskaleion � the Catechetical School � outshone the schools of her rivals by far. During the first half of the 1st century CE and specifically after the destruction of the temple and the fall of Jerusalem in 70 CE, many Jews fled their home country for different parts of the Roman Empire, like Transjordan, Syria and Africa. A number of these Jews � later called Christians � believed in Jesus of Nazareth. In Alexandria, these believers were confronted with different religions, cults and philosophies. The Didaskaleion was founded to rival these religions and cults and to provide the students with the necessary basis for their newly found religion. The lack of literature, on the one hand, and the credibility of the extant literature, on the other, caused great difficulty in reasoning with authority on the Didaskaleion. This is part one of two articles, the second one being constructed around the heads of the School.Intradisciplinary and/or interdisciplinary implications: Research about Africa done by Africans (inhabitants of Africa) need to increase because, in many ways Africa, is silent or silenced about her past. The fundamental question is: �Can anything good come out of Africa?� My answer is, �Yes! Come and see.� Therefore these two articles attempt to indicate the significance of Africa, which was actually the place where Christian Theology was founded. This has intra- as well as interdisciplinary implications. In this case the investigation is done from a theological perspective.
Dealing with corruption in South African civil society: Orientating Christian communities for their role in a post-apartheid context
Authors: De Wet Friedrich W.
Published: May 2015

The way in which the full spectrum of Christian communities are challenged to realign themselves in addressing the impact of corruption on the contemporary South-African society can be a relevant indicator of civil society�s state and functionality in a post-apartheid democratic context. Utilising the interpretative and normative tools of practical-theological research, the researcher attempts to point out markers for Christian communities towards orientating themselves regarding their role in a complex landscape and in an asymmetrically shaped public sphere. The discussion includes an analysis of the current shape of civil society, an interpretation of the complex landscape of perceptions regarding corruption and an overview of the dilemmas faced by some of the major Christian church traditions in the post-apartheid South African context concerning their truthful presence in civil society. The discussion concludes by making a case for the need to anchor the realignment of the prophetic voice and the revitalisation of the transformative presence in a profound and far-reaching theological reorientation. Tension fields that involve critical and constructive action in a situation of endemic corruption cannot be negotiated without ridding the own presence from potential corruptive elements like hidden exclusivity, half-hearted concern and compromise.Intradisciplinary and/or interdisciplinary implications: Making use of the interdisciplinary results of social sciences and civil-society studies, the author provides an overview for Christian communities and their leaders in theologically orientating themselves for an appropriate angle of approach in entering the public sphere with a view on authentic and impactful participation in anti-corruption dialogue and actions. The key finding of the research amounts to the following: Tension fields that involve critical and constructive action in a situation of endemic corruption cannot be negotiated without ridding the own presence from potential corruptive elements like hidden exclusivity, half-hearted concern and compromise.
Absolute continuity, Lyapunov exponents and rigidity I: geodesic flows
Authors: Avila Artur , Viana Marcelo , Wilkinson Amie
Published: May 2015

We consider volume-preserving perturbations of the time-one map of the geodesic flow of a compact surface with negative curvature. We show that if the Liouville measure has Lebesgue disintegration along the center foliation then the perturbation is itself the time-one map of a smooth volume-preserving flow, and that otherwise the disintegration is necessarily atomic.
Nonlinear Vertical Vibration of Tension Leg Platforms with Homotopy Analysis Method
Authors: Reza Arash , Sedighi Hamid M.
Published: May 2015

One of the useful methods for offshore oil exploration in the deep regions is the use of tension leg platforms (TLP). The effective mass fluctuating of the structure which due to its vibration can be noted as one of the important issues about these platforms. With this description, dynamic analysis of these structures will play a significant role in their design. Differential equations of motion of such systems are nonlinear and providing a useful method for its analysis is very important. Also, the amount of added mass coefficient has a direct effect on the level of nonlinearity of partial differential equation of these systems. In this study, Homotopy analysis method has been used for closed form solution of the governing differential equation. Linear springs have been used for modeling the stiffness of this system and the effects of torsion, bending and damping of water have been ignored. In the study of obtained results, the effect of added mass coefficient has been investigated. The results show that increasing of this coefficient decreases the bottom amplitude of fluctuations and the system frequency. The obtained results from this method are in good agreement with the published results on the valid articles.
Heat Transfer in an Upper Convected Maxwell Fluid with Fluid Particle Suspension
Authors: Vajravelu K. , Prasad K. V. , Santhi S. R.
Published: May 2015

An analysis is carried out to study the magnetohydrodynamic (MHD) flow and heat transfer characteristics of an electrically conducting dusty non-Newtonian fluid, namely, the upper convected Maxwell (UCM) fluid over a stretching sheet. The stretching velocity and the temperature at the surface are assumed to vary linearly with the distance from the origin. Using a similarity transformation, the governing nonlinear partial differential equations of the model problem are transformed into coupled non-linear ordinary differential equations and the equations are solved numerically by a second order finite difference implicit method known as the Keller-box method. Comparisons with the available results in the literature are presented as a special case. The effects of the physical parameters on the fluid velocity, the velocity of the dust particle, the density of the dust particle, the fluid temperature, the dust-phase temperature, the skin friction, and the wall-temperature gradient are presented through tables and graphs. It is observed that, Maxwell fluid reduces the wall-shear stress. Also, the fluid particle interaction reduces the fluid temperature in the boundary layer. Furthermore, the results obtained for the flow and heat transfer characteristics reveal many interesting behaviors that warrant further study on the non-Newtonian fluid flow phenomena, especially the dusty UCM fluid flow phenomena.
A Local Fractional Taylor Expansion and Its Computation for Insufficiently Smooth Functions
Authors: Liu Zhifang , Wang Tongke , Gao Guanghua
Published: May 2015

A general fractional Taylor formula and its computation for insufficiently smooth functions are discussed. The Aitken delta square method and epsilon algorithm are implemented to compute the critical orders of the local fractional derivatives, from which more critical orders are recovered by analysing the regular pattern of the fractional Taylor formula. The Richardson extrapolation method is used to calculate the local fractional derivatives with critical orders. Numerical examples are provided to verify the theoretical analysis and the effectiveness of our approach.
Hall MHD and Electron Inertia Effects in Current Sheet Formation at a Magnetic Neutral Line
Authors: Litvinenko Yuri E. , McMahon Liam C.
Published: May 2015

An exact self-similar solution is used to investigate current sheet formation at a magnetic neutral line in incompressible Hall magnetohydrodynamics. The collapse to a current sheet is modelled as a finite-time singularity in the solution for electric current density at the neutral line. We establish that a finite-time collapse to the current sheet can occur in Hall magnetohydrodynamics, and we find a criterion for the finite-time singularity in terms of the initial conditions. We derive an asymptotic solution for the singularity formation and a formula for the singularity formation time. The analytical results are illustrated by numerical solutions, and we also investigate an alternative similarity reduction. Finally, we generalise our solution to incorporate resistive, viscous and electron inertia terms.
Algebraic Theory of Two-Grid Methods
Authors: Notay Yvan
Published: May 2015

About thirty years ago, Achi Brandt wrote a seminal paper providing a convergence theory for algebraic multigrid methods [Appl. Math. Comput., 19 (1986), pp. 23–56]. Since then, this theory has been improved and extended in a number of ways, and these results have been used in many works to analyze algebraic multigrid methods and guide their developments. This paper makes a concise exposition of the state of the art. Results for symmetric and nonsymmetric matrices are presented in a unified way, highlighting the influence of the smoothing scheme on the convergence estimates. Attention is also paid to sharp eigenvalue bounds for the case where one uses a single smoothing step, allowing straightforward application to deflation-based preconditioners and two-level domain decomposition methods. Some new results are introduced whenever needed to complete the picture, and the material is self-contained thanks to a collection of new proofs, often shorter than the original ones.
Multigrid Methods with Newton-Gauss-Seidel Smoothing and Constraint Preserving Interpolation for Obstacle Problems
Authors: Wu Chunxiao , Wan Justin W.L.
Published: May 2015

In this paper, we propose a multigrid algorithm based on the full approximate scheme for solving the membrane constrained obstacle problems and the minimal surface obstacle problems in the formulations of HJB equations. A Newton-Gauss-Seidel (NGS) method is used as smoother. A Galerkin coarse grid operator is proposed for the membrane constrained obstacle problem. Comparing with standard FAS with the direct discretization coarse grid operator, the FAS with the proposed operator converges faster. A special prolongation operator is used to interpolate functions accurately from the coarse grid to the fine grid at the boundary between the active and inactive sets. We will demonstrate the fast convergence of the proposed multigrid method for solving two model obstacle problems and compare the results with other multigrid methods.
Review of Methods Inspired by Algebraic-Multigrid for Data and Image Analysis Applications
Authors: Galun Meirav , Basri Ronen , Yavneh Irad
Published: May 2015

Algebraic Multigrid (AMG) methods were developed originally for numerically solving Partial Differential Equations (PDE), not necessarily on structured grids. In the last two decades solvers inspired by the AMG approach, were developed for non PDE problems, including data and image analysis problems, such as clustering, segmentation, quantization and others. These solvers share a common principle in that there is a crosstalk between fine and coarse representations of the problems, with flow of information in both directions, fine-to-coarse and coarse-to-fine. This paper surveys some of these problems and the AMG-inspired algorithms for their solution.
Характеризация локально нeтеровых многообразий в терминах идемпотентов
Authors: Finogenova Ol'ga Borisovna
Published: May 2015

В работе доказывается, что многообразие ассоциативных
колец локально нeтерово слева и справа
тогда и только тогда, когда любое его конечнопорожденное
кольцо содержит лишь конечное число идемпотентов.
Библиография: 6 названий.
О локальной разрешимости и разрушении решения абстрактного нелинейного интегрального уравнения Вольтерра
Authors: Panin Alexander Anatolyevich
Published: May 2015

Доказана теорема о непродолжаемом решении
для абстрактных интегральных уравнений Вольтерра
с операторнозначными ядрами (непрерывным и полярным). Показано,
что в случае отсутствия глобальной разрешимости $C$-норма решения
не ограниченна, но, вообще говоря, не стремится к бесконечности.
Построен пример уравнения Вольтерра,
непродолжаемое решение которого является неограниченным,
но не бесконечно большим. Показано,
что теоремы о непродолжаемом решении задачи Коши
для абстрактных уравнений первого и
$n$-го (с линейной главной частью) порядков являются
частными случаями доказанных в работе теорем.
Библиография: 33 названия.
Эргодическая теорема для системы обслуживания с ненадежным прибором
Authors: Aibatov Serik Zhagalbaevich
Published: May 2015

Рассматривается одноканальная система обслуживания с ненадежным прибором. Вероятность выхода прибора из строя зависит от состояния случайной среды, которая описывается цепью Маркова. Для этой системы доказана эргодическая теорема. Библиография: 13 названий.
Shifting Attitudes toward Teaching Culture within the Framework of English as an International Language
Authors: Guerra Luis
Published: May 2015

This study deals with the cultural dimensions of EIL, which are analysed based on the following domains: (a) subjects’ attitudes toward teaching about specific cultures (native and non-native); and (b) subjects’ attitudes toward teaching about culture in general. In essence, a view of culture based on native cultures can emerge from three different approaches: it may promote British culture only, it may focus on both the UK and the US, or it may incorporate other English native cultures. Likewise, a more international viewpoint can also be offered from three perspectives: it may refer to ESL contexts only, it may present both ESL and EFL communities – including the local culture – or it may introduce international aspects not specific to any culture. However, the analysis of data in this study indicates that the subjects’ attitudes toward teaching culture do not usually correspond to just one of these perspectives; rather, teachers display a manifold set of beliefs which may at times be closer or more distant to an international approach to teaching culture.
Scouting the Desert of the Real: Avant-Gardism of the Avant-Pop
Authors: Krevel Mojca
Published: May 2015

The paper examines the legacy of the European historical Avant-Gardes from the perspective of the shift of paradigms immanent in the formation of the Postmodern epoch. The existing theories generally regard the Avant-Gardes as an unsuccessful attempt to redefine the function of art in the social, cultural and economic environment of the early 20th century. Examining the productivity and relevance of the historical Avant-Gardes from the perspective of the Avant-Pop, the first thoroughly Postmodern literary movement, I intend to show how the strategies of fragmentation and the breaking of organicity not only quintessentially defined the manner in which Modernity and its art came to an end, but how they also provided the basis forthe formation of culture and art that no longer functions according to Cartesian principles.
Slovene-English Contrastive Phraseology: Lexical Collocations
Authors: Jurko Primož
Published: May 2015

Phraseology is seen as one of the key elements and arguably the most productive part of any language. %e paper is focused on collocations and separates them from other phraseological units, such as idioms or compounds. Highlighting the difference between a monolingual and a bilingual (i.e. contrastive) approach to collocation, the article presents two distinct classes of collocations: grammatical and lexical. %e latter, treated contrastively, represent the focal point of the paper, since they are an unending source of translation errors to both students of translation and professional translators. %e author introduces a methodology of systematic classification of lexical collocations applied on the Slovene-English language pair and based on structural (lexical congruence) and semantic (translational predictability) criteria.
Contrasts in Metaphysical Writing: John Donne and Emily Dickinson
Authors: Braček Tadej
Published: May 2015

This paper starts by stating what metaphysical poetry is, what its characteristics are, and who the metaphysical poets are. Later the paper focuses on Emily Dickinson’s poetry and confirms the thesis that she can be considered a metaphysical poet. The third thing the paper deals with is to what extent Donne’s and Dickinson’s poetry as well as Donne’s Sermons correspond to the Calvinist theology, which is the common credo of the Churches to which they belong. A further issue the paper debates about is rhetorical devices in the metaphysical service.The last aspect of Donne’s and Dickinson’s writing that the essay explores is their attitude towards truth.
Macrostructural Treatment of Multi-word Lexical Items
Authors: Vrbinc Alenka
Published: May 2015

The paper discusses the macrostructural treatment of multi-word lexical items in mono- and bilingual dictionaries. First, the classification of multi-word lexical items is presented, and special attention is paid to the discussion of compounds – a specific group of multi-word lexical items that is most commonly afforded headword status but whose inclusion in the headword list may also depend on spelling. Then the inclusion of multi-word lexical items in monolingual dictionaries is dealt with in greater detail, while the results of a short survey on the inclusion of five randomly chosen multi-word lexical items in seven English monolingual dictionaries are presented. The proposals as to how to treat these five multi-word lexical items in bilingual dictionaries are presented in the section about the inclusion of multi-word lexical items in bilingual dictionaries. The conclusion is that it is most important to take the users’ needs into consideration and to make any dictionary as user friendly as possible.
Voice Onset Time in Serbian and Serbian English
Authors: Čubrović Biljana
Published: May 2015

In this paper, the acoustic facts of Voice Onset Time (VOT) are exemplified by looking at two virtually different languages in terms of recognizing VOT as a distinctive phonological parameter. Selected tokens of Serbian and Serbian English are recorded in carrier sentences and analysed acoustically, as spoken by four proficient Serbian speakers of EFL. The results show that, although Serbian does not recognize VOT as a parameter creating phonological distinctions, advanced non-native speakers of English are capable of learning how to relate the oral and laryngeal gestures in order to produce more native-like pronunciations of English voiceless stops in the phonetic contexts where English /p t k/ are expected to have a long lag. Special attention is drawn to CV sequences whose VOT values deviate in the two languages, as well as to those where VOTs are similar, which can be used to raise the awareness of this phonetic phenomenon in a Serbian EFL learner.
The LANDFIRE Refresh Strategy: Updating the National Dataset
Authors: Nelson Kurtis J. , Connot Joel , Peterson Birgit , Martin Charley
Published: May 2015

The LANDFIRE Program provides comprehensive vegetation and fuel datasets for the entire United States. As with many large-scale ecological datasets, vegetation and landscape conditions must be updated periodically to account for disturbances, growth, and natural succession. The LANDFIRE Refresh effort was the first attempt to consistently update these products nationwide. It incorporated a combination of specific systematic improvements to the original LANDFIRE National data, remote sensing based disturbance detection methods, field collected disturbance information, vegetation growth and succession modeling, and vegetation transition processes. This resulted in the creation of two complete datasets for all 50 states: LANDFIRE Refresh 2001, which includes the systematic improvements, and LANDFIRE Refresh 2008, which includes the disturbance and succession updates to the vegetation and fuel data. The new datasets are comparable for studying landscape changes in vegetation type and structure over a decadal period, and provide the most recent characterization of fuel conditions across the country. The applicability of the new layers is discussed and the effects of using the new fuel datasets are demonstrated through a fire behavior modeling exercise using the 2011 Wallow Fire in eastern Arizona as an example.
Contrasting Fire Regimes in a Seasonally Dry Tropical Forest and a Savanna Ecosystem in the Western Ghats, India
Authors: Kodandapani Narendran
Published: May 2015

Tropical dry forests and savannas constitute more than half of all tropical forests and grasslands, but little is known about forest fire regimes within these two extensive types of ecosystems. Forest fire regimes in a predominantly dry forest in India, the Nilgiri landscape, and a predominantly savanna ecosystem in the Sathyamangalam landscape, were examined. Remote sensing data were applied to delineate burned areas, determine fire size characteristics, and to estimate fire-rotation intervals. Belt transects (0.5 ha) were used to estimate forest structure, diversity, and fuel loads. Mean area burned, mean number of fires, and mean fire size per year were substantially higher in the Nilgiri landscape compared to the Sathyamangalam landscape. Mean fire-rotational interval was 7.1 yr in the Nilgiri landscape and 44.1 yr in the Sathyamangalam landscape. Tree (≥10 cm diameter at breast height) species diversity, tree density, and basal area were significantly higher in the Nilgiri landscape compared to the Sathyamangalam landscape. Total fuel loads were significantly higher in tropical dry and moist deciduous forests in the Nilgiri landscape, but total fuel loads were higher in the tropical dry thorn forests of the Sathyamangalam landscape. Thus, the two landscapes revealed contrasting fire regimes and forest characteristics, with more and four-fold larger fires in the Nilgiri landscape. The dry forests and savannas could be maintained by a combination of factors, such as fire, grazing pressures, and herbivore populations. Understanding the factors maintaining these two ecosystems will be critical for their conservation.
Predicting Burned Areas of Forest Fires: an Artificial Intelligence Approach
Authors: Castelli Mauro , Vanneschi Leonardo , Popovič Aleš
Published: May 2015

Forest fires importantly influence our environment and lives. The ability of accurately predicting the area that may be involved in a forest fire event may help in optimizing fire management efforts. Given the complexity of the task, powerful computational tools are needed for predicting the amount of area that will be burned during a forest fire. The purpose of this study was to develop an intelligent system based on genetic programming for the prediction of burned areas, using only data related to the forest under analysis and meteorological data. We used geometric semantic genetic programming based on recently defined geometric semantic genetic operators for genetic programming. Experimental results, achieved using a database of 517 forest fire events between 2000 and 2003, showed the appropriateness of the proposed system for the prediction of the burned areas. In particular, results obtained with geometric semantic genetic programming were significantly better than those produced by standard genetic programming and other state of the art machine learning methods on both training and out-of-sample data. This study suggests that deeper investigation of genetic programming in the field of forest fires prediction may be productive.
Emissions of nitrogen oxides from US urban areas: estimation from Ozone Monitoring Instrument retrievals for 2005–2014
Authors: Lu Z. , Streets D. G. , de Foy B. , Lamsal L. N. , Duncan B. N. , Xing J.
Published: May 2015

Abstract. Satellite remote sensing of tropospheric nitrogen dioxide (NO2) can provide valuable information for estimating surface nitrogen oxides (NOx) emissions. Using an exponentially-modified Gaussian (EMG) method and taking into account the effect of wind on observed NO2 distributions, we estimate three-year moving-average emissions of summertime NOx from 35 US urban areas directly from NO2 retrievals of the Ozone Monitoring Instrument (OMI) during 2005–2014. Following the conclusions of previous studies that the EMG method provides robust and accurate emission estimates under strong-wind conditions, we derive top-down NOx emissions from each urban area by applying the EMG method to OMI data with wind speeds greater than 3–5 m s−1. Meanwhile, we find that OMI NO2 observations under weak-wind conditions (i.e., < 3 m s−1) are qualitatively better correlated with the surface NOx source strength in comparison to all-wind OMI maps; and therefore we use them to calculate the satellite-observed NO2 burdens of urban areas and compare with NOx emission estimates. The EMG results show that OMI-derived NOx emissions are highly correlated (R > 0.93) with weak-wind OMI NO2 burdens as well as bottom-up NOx emission estimates over 35 urban areas, implying a linear response of the OMI observations to surface emissions under weak-wind conditions. The simultaneous, EMG-obtained, effective NO2 lifetimes (~3.5 ± 1.3 h), however, are biased low in comparison to the summertime NO2 chemical lifetimes. In general, isolated urban areas with NOx emission intensities greater than ~ 2 Mg h−1 produce statistically significant weak-wind signals in three-year average OMI data. From 2005 to 2014, we estimate that total OMI-derived NOx emissions over all selected US urban areas decreased by 49%, consistent with reductions of 43, 47, 49, and 44% in the total bottom-up NOx emissions, the sum of weak-wind OMI NO2 columns, the total weak-wind OMI NO2 burdens, and the averaged NO2 concentrations, respectively, reflecting the success of NOx control programs for both mobile sources and power plants. The decrease rates of these NOx-related quantities are found to be faster (i.e., −6.8 to −9.3% yr−1) before 2010 and slower (i.e., −3.4 to −4.9% yr−1) after 2010. For individual urban areas, we calculate the R values of pair-wise trends among the OMI-derived and bottom-up NOx emissions, the weak-wind OMI NO2 burdens, and ground-based NO2 measurements; and high correlations are found for all urban areas (median R = 0.8), particularly large ones (R up to 0.97). The results of the current work indicate that using the EMG method and considering the wind effect, the OMI data allow for the estimation of NOx emissions from urban areas and the direct constraint of emission trends with reasonable accuracy.
A new method for the absolute radiance calibration for UV/vis measurements of scattered sun light
Authors: Wagner T. , Beirle S. , Dörner S. , Penning de Vries M. , Remmers J. , Rozanov A. , Shaiganfar R.
Published: May 2015

Abstract. Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds and the short wave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV/vis instruments that measure the spectrally resolved sky radiance, like for example zenith sky Differential Optical Absorption Spectroscopy (DOAS-) instruments or Multi-AXis (MAX-) DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method clear sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about <7%. For wavelengths below about 330 nm it is essential that the ozone column density during the measurements is constant and known.
Effective resolution concepts for lidar observations
Authors: Iarlori M. , Madonna F. , Rizi V. , Trickl T. , Amodeo A.
Published: May 2015

Abstract. Since its first establishment in 2000, EARLINET (European Aerosol Research Lidar NETwork) has been devoted to providing, through its database, exclusively quantitative aerosol properties, such as aerosol backscatter and aerosol extinction coefficients, the latter only for stations able to retrieve it independently (from Raman or High Spectral Resolution Lidars). As these coefficients are provided in terms of vertical profiles, EARLINET database must also include the details on the range resolution of the submitted data. In fact, the algorithms used in the lidar data analysis often alter the spectral content of the data, mainly working as low pass filters with the purpose of noise damping. Low pass filters are mathematically described by the Digital Signal Processing (DSP) theory as a convolution sum. As a consequence, this implies that each filter's output, at a given range (or time) in our case, will be the result of a linear combination of several lidar input data relative to different ranges (times) before and after the given range (time): a first hint of loss of resolution of the output signal. The application of filtering processes will also always distort the underlying true profile whose relevant features, like aerosol layers, will then be affected both in magnitude and in spatial extension. Thus, both the removal of noise and the spatial distortion of the true profile produce a reduction of the range resolution. This paper provides the determination of the effective resolution (ERes) of the vertical profiles of aerosol properties retrieved starting from lidar data. Large attention has been addressed to provide an assessment of the impact of low-pass filtering on the effective range resolution in the retrieval procedure.
On the relationship between ecosystem-scale hyperspectral reflectance and CO2 exchange in European mountain grasslands
Authors: Balzarolo M. , Vescovo L. , Hammerle A. , Gianelle D. , Papale D. , Tomelleri E. , Wohlfahrt G.
Published: May 2015

Abstract. In this paper we explore the skill of hyperspectral reflectance measurements and vegetation indices (VIs) derived from these in estimating carbon dioxide (CO2) fluxes of grasslands. Hyperspectral reflectance data, CO2 fluxes and biophysical parameters were measured at three grassland sites located in European mountain regions using standardized protocols. The relationships between CO2 fluxes, ecophysiological variables, traditional VIs and VIs derived using all two-band combinations of wavelengths available from the whole hyperspectral data space were analysed. We found that VIs derived from hyperspectral data generally explained a large fraction of the variability in the investigated dependent variables but differed in their ability to estimate midday and daily average CO2 fluxes and various derived ecophysiological parameters. Relationships between VIs and CO2 fluxes and ecophysiological parameters were site-specific, likely due to differences in soils, vegetation parameters and environmental conditions. Chlorophyll and water-content-related VIs explained the largest fraction of variability in most of the dependent variables. Band selection based on a combination of a genetic algorithm with random forests (GA–rF) confirmed that it is difficult to select a universal band region suitable across the investigated ecosystems. Our findings have major implications for upscaling terrestrial CO2 fluxes to larger regions and for remote- and proximal-sensing sampling and analysis strategies and call for more cross-site synthesis studies linking ground-based spectral reflectance with ecosystem-scale CO2 fluxes.
A high-resolution ocean and sea-ice modelling system for the Arctic and North Atlantic oceans
Authors: Dupont F. , Higginson S. , Bourdallé-Badie R. , Lu Y. , Roy F. , Smith G. C. , Lemieux J.-F. , Garric G. , Davidson F.
Published: May 2015

Abstract. As part of the CONCEPTS (Canadian Operational Network of Coupled Environmental PredicTion Systems) initiative, a high-resolution (1/12°) ice–ocean regional model is developed covering the North Atlantic and the Arctic oceans. The long-term objective is to provide Canada with short-term ice–ocean predictions and hazard warnings in ice-infested regions. To evaluate the modelling component (as opposed to the analysis – or data-assimilation – component, which is not covered in this contribution), a series of hindcasts for the period 2003–2009 is carried out, forced at the surface by the Canadian GDPS reforecasts (Smith et al., 2014). These hindcasts test how the model represents upper ocean characteristics and ice cover. Each hindcast implements a new aspect of the modelling or the ice–ocean coupling. Notably, the coupling to the multi-category ice model CICE is tested. The hindcast solutions are then assessed using a verification package under development, including in situ and satellite ice and ocean observations. The conclusions are as follows: (1) the model reproduces reasonably well the time mean, variance and skewness of sea surface height; (2) the model biases in temperature and salinity show that while the mean properties follow expectations, the Pacific Water signature in the Beaufort Sea is weaker than observed; (3) the modelled freshwater content of the Arctic agrees well with observational estimates; (4) the distribution and volume of the sea ice are shown to be improved in the latest hindcast due to modifications to the drag coefficients and to some degree to the ice thickness distribution available in CICE; (5) nonetheless, the model still overestimates the ice drift and ice thickness in the Beaufort Gyre.