bluuebunny/crossref_metadata_2025 huggingface dataset:
Massive Access Control in Machine-to-Machine Communications
Authors: Verma Pawan Kumar , Verma Rajesh , Prakash Arun , Tripathi Rajeev
Published: June 2018

This chapter proposes a new hybrid MAC protocol for direct communication among M2M devices with gateway coordination. The proposed protocol combines the benefits of both contention-based and reservation-based MAC schemes. The authors assume that the contention and reservation portion of M2M devices is a frame structure, which is comprised of two sections: contention interval (CI) and transmission interval (TI). The CI duration follows p-persistent CSMA mechanism, which allows M2M devices to contend for the transmission slots with equal priorities. After contention, only those devices which have won time-slots are allowed to transmit data packets during TI. In the proposed MAC scheme, the TI duration follows TDMA mechanism. Each M2M transmitter device and its corresponding one-hop distant receiver communicate using IEEE 802.11 DCF protocol within each TDMA slot to overcome various limitations of TDMA mechanism. The authors evaluate the performance of the proposed hybrid MAC protocol in terms of aggregate throughput, average transmission delay, channel utility, and energy consumption.
Visualization-Driven Approach to Fraud Detection in the Mobile Money Transfer Services
Authors: Novikova Evgenia , Kotenko Igor
Published: June 2018

Mobile money transfer services (MMTS) are widely spread in the countries lacking conventional financial institutions. Like traditional financial systems they can be used to implement financial frauds. The chapter presents a novel visualization-driven approach to detection of the fraudulent activity in the MMTS. It consists in usage of a set of interactive visualization models supported by outlier detection techniques allowing to construct comprehensive view on the MMTS subscriber behavior according to his/her transaction activity. The key element of the approach is the RadViz visualization that helps to identify groups with similar behavior and outliers. The scatter plot visualization of the time intervals with transaction activity supported by the heat map visualization of the historical activity of the MMTS subscriber is used to conduct analysis of how the MMTS users' transaction activity changes over time and detect sudden changes in it. The results of the efficiency evaluation of the developed visualization-driven approach are discussed.
Potential Applications of Nanomaterials in Wastewater Treatment
Authors: Sadegh Hamidreza , Ali Gomaa A. M.
Published: June 2018

High-quality water is one of the most important challenges around the world. Conventional techniques of wastewater treatment need to be developed. Therefore, finding sustainable, environmentally friendly, and efficient treatment techniques is required. In this regard, due to the extraordinary potential of nanotechnology resulted from nanoscale size characteristics, recently nanomaterials have been the subject of novel research and development worldwide. In this chapter, the authors review recent development of the direct applications of nanomaterial as an adsorbent in adsorption systems for integrating nanoparticles into conventional treatment technologies for wastewater treatment, especially a wide range of candidate nanomaterials and its properties. In addition, advantages and limitations as compared to existing processes are discussed.
Instant Messaging Chat Bot
Authors: Han Min Chung
Published: June 2018

Recently there has been a resurgence of chat bot use among businesses, which employ them as part of their marketing strategy. To provide better insight into instant messaging chat bots as a marketing tool, the present research focuses on mobile users' current understanding and perceptions of chat bots. This study examines what mobile consumers think of instant messaging chat bots, and whether consumers are willing to use the new chat bots. This study employs focus group interviews and online surveys to examine consumers' perceptions. The results indicate that a majority of mobile users have employed chat bots for customer service and for entertainment. Mobile users found instant messaging chat bots easy to use and useful, but not necessarily entertaining.
Are Millennials Ready for the Internet of Things?
Authors: Barbosa Belem , Filipe Sandra , Santos Claudia Amaral , Simões Dora
Published: June 2018

A lot has been said about the digital natives and their natural way of integrating the internet in their daily activities. Millennials have been considered a unique segment of consumers by researchers and practitioners alike, due to their ability and propensity to adopt and adapt new media to their daily routine. Although it is expectable that they are particularly keen on embracing IoT, extant literature is scarce on their views on the adoption of IoT to their home, work, and leisure activities. In this chapter, the authors analyze the potential of the millennial segment to IoT products and services. Results of a qualitative study with Portuguese consumers are included and provide interesting cues to marketers working with IoT offers.
On the Use of Digital Platforms to Support SME Internationalization in the Context of Industrial Business Associations
Authors: Costa Eric , Soares António Lucas , Pinho de Sousa Jorge
Published: June 2018

The digital economy is creating disruptions in traditional industries and markets. Industrial business associations (IBAs) may face serious challenges in a near future to meet the needs and requirements of their members, particularly in supporting their growing international trade activities and internationalization processes. Digital platforms are already transforming different types of businesses across all markets. An IBA may use a digital platform, not only to keep up with the current technological trends of markets, but also to improve the internationalization support provided to their associate small and medium enterprises (SMEs). Therefore, the aim of this chapter is to present the view of these potential digital platforms' managers, by presenting the results of an exploratory field research based on 24 interviews with IBAs from Portugal, France, and the UK. Another goal is to identify current digital platforms that are being used by IBAs and to critically evaluate their potential for supporting internationalization processes of SMEs. By using these findings, a set of requirements and features for digital platforms supporting SME internationalization in the context of IBAs are derived in this chapter. These results can be used by platform designers and by IBAs for designing and developing more effective digital platforms that can meet the specific internationalization needs of their users and managers.
Information Strategy
Authors: Maravilhas Sérgio , Melo Paulo , Oliveira Sérgio Goes
Published: June 2018

In this chapter, the implementation of an information strategy project in a Portuguese real estate company is analyzed. This involves its framing—historical and socio-economic—and a brief description of the activity sector in which the company operates. Several well managed projects have been developed to improve the competitive position of the company, but without focus all the activities lose strength because they might not reach their proposed targets. Some tools to identify the information needs of business activity developed are described, as well as the role of information as a promoter of competitive advantages. Social media tools were utilized and proved to be a great strategic decision. To conclude, a few reminders of the factors to consider in developing the information strategy to implement and that information management without a strategy could result in several diversified decisions without any positive consequence for the organization.
How Fablabs Manage the Knowledge They Create
Authors: Maravilhas Sérgio , Martins Joberto
Published: June 2018

A collaborative space for stimulating creativity is a place of learning through the exchange and sharing of knowledge and experience among its members. It allows the leveraging of innovation through the use of technological resources available in the space, stimulating the creativity of its participants, enabling the development of products and solutions based on personal projects—do it yourself (DIY)—from ideation, or the construction supported on knowledge developed by other elements together, collaboratively, enhancing the final result—do it with others (DIWO). A research project is being held to create a new lab, or transform and adapt one of the existing lab's, in a Fab Lab or a Maker Space to let students, teachers, and staff give wings to their imagination and develop innovative solutions to solve real problems while they interact and exchange tacit knowledge, making it explicit after concluding their projects when they share their research reports.
Reviewing Information Quality
Authors: Jamil George Leal
Published: June 2018

Revisiting a concept is a mandatory approach when new technologies emerge. This chapter presents a reviewed study, based on a previous publication, about information quality. As it happened in the first attempt to study and develop this concept, it remains challenging, as this context contemplates both tangible and intangible observations for two unlimited parts—information and quality—researched isolated, with its own alternatives, methods and objectives for several years and from different points of view. This chapter's approach is to bring additional work published since the original one and develop conclusions reached at that time, providing a new level of comprehension, which allows the continuity of this debate of information quality, considering the emerging strong trend of analytics processing and informational service offering.
Teaching Critical Thinking
Authors: Torff Bruce
Published: June 2018

This chapter outlines how to teach critical-thinking skills is a central issue at home, in school, on the job, and in life. Outcomes of critical-thinking pedagogies are optimized under three conditions: 1) when thinking skills are integrated with disciplinary content, not sequentially following a content presentation; 2) when thinking skills are taught as utilized in specific domains/disciplines, not decontextualized or treated as domain-general; and 3) when thinking skills are emphasized for all learners, not just advantaged ones with greater prior knowledge or academic ability. Accordingly, teaching critical thinking might well be structured to be integrative, domain-specific, and equitable.
Essential Skills for the 21st Century Workforce
Authors: Short Maureen N. , Keller-Bell Yolanda
Published: June 2018

This chapter contends that increasing technological innovation has disrupted and continues to disrupt the labor markets making some jobs obsolete and workers redundant. The key to success in the twenty-first century and future labor markets is to combine hard and soft skills into a comprehensive package tailored to specific needs including the ability to think clearly about complex problems, apply creative and innovation solutions to solve problems, and apply new knowledge and skills in new settings. This chapter will provide a discussion of some of the reasons underlying the demand for higher workforce skills and a descriptive overview of curricula and pedagogy that promote students' acquisition and application of critical thinking skills as well as other skills considered essential for 21st century workforce.
Machine Learning
Authors: Cauvin Bertrand , Benning Pierre
Published: June 2018

A Bridge Data Dictionary contains an exhaustive list of terms used in the field of bridges. These terms are classified in systems in order to avoid any lacks, to identify all the expected object attributes, and to allow machines to understand the associated concepts. The main objectives of a Bridge Data Dictionary are many: ensure the sustainability of information over time; facilitate information exchange between the actors of the same project; ensure interoperability between the software packages. Other objectives have been reached during the process: to test a working methodology to be applied by other infrastructure domains (Roads, Rails, Tunnels, etc.); to check the current functions and capabilities of a buildingSMART Data Dictionary platform; and to define a common term list, in order to facilitate standardization and IFC-Bridge classes' development.
Smart Device Authentication Based on Online Handwritten Script Identification and Word Recognition in Indic Scripts Using Zone-Wise Features
Authors: Ghosh Rajib , Roy Partha Pratim , Kumar Prabhat
Published: June 2018

Secure authentication is a vital component for device security. The most basic form of authentication is by using passwords. With the evolution of smart devices, selecting stronger and unbreakable passwords have become a challenging task. Such passwords if written in native languages tend to offer improved security since attackers having no knowledge of such scripts finding it hard to crack. This article proposes two zone-wise feature extraction approaches - zone-wise structural and directional (ZSD) and zone-wise slopes of dominant points (ZSDP), to recognize online handwritten script and word in four major Indic scripts - Devanagari, Bengali, Telugu and Tamil. These features have been used separately and in combination in HMM-based platform for recognition purpose. The dimension reduction of the ZSD-ZSDP combination with factor analysis has shown the best performance in all the four scripts. This work can be utilized for setting up the authentication schemes with the Indic scripts' passwords thus rendering it difficult to crack by hackers having no knowledge of such scripts.
Security Integration in DDoS Attack Mitigation Using Access Control Lists
Authors: Yadav Sumit Kumar , Sharma Kavita , Arora Arushi
Published: June 2018

In this article, the authors propose a DDoS mitigation system through access list-based configurations, which are deployed at the ISP (Internet Service Provider's) edge routers to prohibit DDoS attacks over ISPs' networks traffic. The effectiveness of the proposed system relies heavily on the willingness of ISPs in implementing the system. Once each ISP implements the system, most attacks can easily be stopped close to their point of origin. The main challenge is to implement such a system with the fixed amount of memory and available processing power with routers. A coordinated effort by participating ISPs filters out attacks close to their source, reducing the load on other routers. The suspicious traffic is first filtered out based on their source IP address. The authors also implemented the WRED algorithm for their case and conduct GNS3 experiments in a simulated environment.
A Web Portal for Rice Crop Improvements
Authors: Baurley James W. , Budiarto Arif , Kacamarga Muhamad Fitra , Pardamean Bens
Published: June 2018

High quality models of factors influencing rice crop yield are needed in countries where rice is a staple food. These models can help select optimal rice varieties for expected field conditions. Development of a system to help scientist track and make decisions using this data is challenging. It involves incorporation of complex data structures - genomic, phenotypic, and remote sensing - with computationally intensive statistical modeling. In this article, the authors present a web portal designed to help researchers to manage and analyze their datasets, apply machine learning to detect how factors taken together influence crop production, and summarize the results to help scientists make decisions based on the learned models. The authors developed the system to be easily accessed by the entire team including rice scientist, genetics, and farmers. As such, they developed a system on a server architecture comprised of a SQLite database, a web interface developed in Python, the Celery job scheduler, and statistical computing in R.
Modernizing Legacy Systems
Authors: Vijaya Aparna , Venkataraman Neelanarayanan
Published: June 2018

Cloud computing is a paradigm which has changed the way organizations develop, manage, and deploy their applications. Most of the resources are available at low costs in this technology and it creates new opportunities for organizations to move their existing applications to the cloud for modernization. But this modernization also comes at a price. The authors present a model-driven approach to address the challenges in application modernization and focus on the application migration to cloud. Most of the cloud applications are very specific to a particular vendor's features or services. The proposed methodology addresses the challenge of vendor lock-in also. The authors present their theoretical details and experience with two pilot projects where they have applied the proposed approach.
Effects of human impacts on diversity and distribution of chironomids (Diptera: Chironomidae) in prealpine springs
Authors: Lencioni Valeria , Mezzanotte Enrico , Spagnol Camilla , Latella Leonardo
Published: June 2018

Diversity and distribution of chironomid fauna (Diptera: Chironomidae) in 36 springs in the Italian Prealps (Veneto and Trentino NE-Italy, 46°N, 10-11°E) was studied in relation to altitude, spring type and grade of disturbance. The springs were located between 62 and 1710 m asl of altitude, in three calcareous mountain areas (Mt. Baldo, Mts. Lessini and Mt. Pasubio). They differed in conservation status (natural, moderately and highly disturbed) and belonged to five hydromorphological types (rheocrene, limnocrene, rheohelocrene, rheolimnocrene, rheohygropetric). Each spring was surveyed once, between early summer and autumn, within 50 m of the spring’s source (eucrenal). A total of 4198 chironomid larvae and pupae were sorted from 111 macroinvertebrate samples collected, belonging to five subfamilies (Tanypodinae, Diamesinae, Prodiamesinae, Orthocladiinae and Chironominae), 41 genera and 60 species/groups of species, and three juveniles taxa. As expected, Orthocladiinae accounted for a large part of specimens (88%) and species (74%), with Tvetenia calvescens/bavarica as the most frequent and abundant taxon, shared by pristine and disturbed springs and by all spring types. Most taxa were found in few sites, and frequencies declined gradually for most wider distributed species. A high number (74%) of rare (= present in less than 10% of sites) taxa were found and from one to 23 taxa were identified per spring. Maximum richness occurred in moderately disturbed (Shannon-H = 1.29±0.60) springs, located at medium-high altitude (385-1266 m asl), according to the intermediate disturbance hypothesis. Even the evenness (Equitability-J) was higher as average in these springs. A Cluster Analysis run on Bray-Curtis similarity index highlighted a high similarity i) between the chironomid assemblages of moderately disturbed and natural springs (44 species in each spring group, with 29 species in common), and ii) between rheocrene and rheohelocrene types, thus the springs with the highest microhabitat heterogeneity. High individuality of springs was revealed, and new information about non-biting midges autecology provided. The utility of chironomids as bioindicators of water quality and ecological state of springs was confirmed, with some species e associated with high disturbance level (e.g., Polypedilum nubeculosum gr. to water intake works) and others with pristine conditions (e.g., Pseudodiamesa branickii).
Job satisfaction and its relationship with organisational commitment: A Democratic Republic of Congo organisational perspective
Authors: Mitonga-Monga Jeremy , Flotman Aden-Paul , Cilliers Frans
Published: June 2018

Orientation: The modern workplace, which is characterised by increasing turbulence and debilitating uncertainty, has led to renewed focus on whether employees experience satisfaction and how they commit themselves to the organisation.Research purpose: The aim of this study was to measure the nature of the relationship between employees’ levels of job satisfaction (JS) and organisational commitment (OC) in a public railway organisation in the Democratic Republic of Congo (DRC).Motivation for the study: Although previous researchers have found evidence of the relationship between JS and OC in Western countries, there seems to be a paucity of research on the relationship between JS and OC in a developing country context such as that of the DRC. The results could make a valuable contribution to the current literature debate on these two constructs (JS and OC) and possibly employees’ intention to stay in their present organisation.Research design, approach and method: A cross-sectional survey design was used employing the Job Satisfaction Questionnaire and the Organisational Commitment Scale. The sample (n = 839) comprised permanently employed staff. Correlations and regression analyses were conducted. The results indicated that employees’ JS related positively to their level of OC and that JS predicted OC.Practical and managerial implications: The results should also have interesting implications for top management and human resource practitioners. They could use this information to study how organisational psychological attachment is fostered in order to potentially master other organisational dynamics. The information could also be used to create positive working conditions with a view to reinforcing OC. JS manifested as a critical driver of OC, which could result in superior business performance. Management could use the results to create a working environment that actively fosters satisfaction and boosts employees’ level of commitment.Contribution or value-add: The results should contribute to the body of knowledge on the relationship between JS and OC in the context of a developing economy and highlight the practical implications for line managers and behavioural and wellness practitioners.
A heavy goods vehicle fleet forecast for South Africa
Authors: Havenga Jan H. , Le Roux Phillippus P.T. , Simpson Zane P.
Published: June 2018

Purpose: To develop and apply a methodology to calculate the heavy goods vehicle fleet required to meet South Africa’s projected road freight transport demand within the context of total surface freight transport demand.Methodology: Total freight flows are projected through the gravity modelling of a geographically disaggregated input–output model. Three modal shift scenarios, defined over a 15-year forecast period, combined with road efficiency improvements, inform the heavy goods vehicle fleet for different vehicle types to serve the estimated future road freight transport demand.Findings: The largest portion of South Africa’s high and growing transport demand will remain on long-distance road corridors. The impact can be moderated through the concurrent introduction of domestic intermodal solutions, performance-based standards in road freight transport and improved vehicle utilisation. This presupposes the prioritisation of collaborative initiatives between government, freight owners and logistics service providers.Research limitations: (1) The impact of short-distance urban movements on fleet numbers is not included yet. (2) Seasonality, which negatively influences bi-directional flows, is not taken into account owing to the annual nature of the macroeconomic data. (3) The methodology can be applied to other countries; the input data are however country-specific and findings can therefore not be generalised. (4) The future possibility of a reduction in absolute transport demand through, for example, reshoring have not been modelled yet.Practical implications: Provides impetus for the implementation of domestic intermodal solutions and road freight performance-based standards to mitigate the impact of growing freight transport demand.Societal implications: More efficient freight transport solutions will reduce national logistics costs and freight-related externalities.Originality: Develops a methodology for forecasting the heavy goods vehicle fleet within the context of total freight transport to inform government policy and industry actions.
Investigating the interaction between human immunodeficiency virus, nutrition, and disability: A cross-sectional observational study
Authors: Myezwa Hellen , Hanass-Hancock Jill , Pautz Nikolas
Published: June 2018

Background: The average lifespan of people with human immunodeficiency virus (HIV) has increased because of the enhanced access to anti-retroviral treatment. This increased longevity has led to a heightened focus on the comorbidities which may arise, allowing a clearer understanding of the contextual, personal, psychological and functional problems and their interrelations. Disability (functional limitations) and insufficient nutritional intake may interact cyclically with HIV and/or acquired immunodeficiency syndrome (AIDS); however, no research to date has investigated this interaction. Aims: The objective of this article was to report on the nutritional outcomes using albumin and body mass index outcomes as a subset of a larger study among adults living with HIV and/or AIDS. Setting: This study was conducted at a large HIV clinic based in an urban area in Johannesburg, South Africa, which provides HIV treatment and support to over 6000 persons with HIV and TB. This clinic is part of a large public health regional hospital where extensive HIV research is undertaken. Methods: This study was a cross-sectional observational study. The sample composed of 278 participants between 18 and 65 years of age and had been on highly active antiretroviral therapy (HAART) for more than six months. Statistical analyses were performed using the Statistical Package for the Social Sciences. Results: The results indicated that albumin level had significant inverse associations with functional limitations and physical health symptoms. Women were significantly more likely to have lower nutritional levels. A logistic regression analysis suggested that gender and physical health symptoms were the primary predictors of albumin levels. Conclusion: The findings presented in this article can be applied to HIV and/or AIDS treatment programmes, such as HAART. It re-emphasises the importance of providing individuals on anti-retroviral therapy with affordable and adequate nutrition, education on the importance of nutritional intake and the benefits of potentially adopting supplement programmes. As females seem to be more adversely affected by low nutritional levels, with the findings showing an increased likelihood of developing physical health symptoms, focus also needs to be given to cultural or social factors that impact nutritional intake in women.
How well do stratospheric reanalyses reproduce high-resolution satellite temperature measurements?
Authors: Wright Corwin J. , Hindley Neil P.
Published: June 2018

Abstract. Atmospheric reanalyses are data-assimilating weather models which are widely used as proxies for the true state of the atmosphere in the recent past, particularly for the stratosphere, where historical observations are sparse. But how realistic are these stratospheric reanalyses? Here, we resample stratospheric temperature data from six modern reanalyses (CFSR, ERA-5, ERA-Interim, JRA-55, JRA-55C and MERRA-2) to produce synthetic satellite observations, which we directly compare to retrieved temperatures from the COSMIC, HIRDLS and SABER instruments and to brightness temperatures from the AIRS instrument for the ten-year period 2003–2012. We explicitly sample standard public-release products in order to best assess their suitability for typical use cases. We find that all-time all-latitude correlations between limb sounder observations and synthetic observations from full-input reanalyses are 0.97–0.99 at 30 km altitude, falling to 0.84–0.94 at 50 km. The highest correlations are seen at high latitudes and the lowest in the sub-tropics, but root-mean-square (RMS) differences are highest (10 K or greater) in high-latitude winter. At all latitudes, differences increase with increasing height. High-altitude differences become especially large during disrupted periods such as the post-sudden stratospheric warming recovery phase, where zonal-mean differences can be as high as 18 K between different datasets. We further show that, for the current generation of reanalysis products, a full-3D sampling approach is always required to produce realistic synthetic AIRS observations, but is almost never required to produce realistic synthetic HIRDLS observations. For synthetic SABER and COSMIC observations full-3D sampling is required in equatorial regions and regions of high gravity-wave activity but not otherwise. Finally, we use cluster-analyses to show that full-input reanalyses are more tightly correlated with each other than with observations, even observations which they assimilate. This may suggest that these reanalyses are over-tuned to match their comparators. If so, this could have significant implications for future reanalysis development.
Assessing a low-cost methane sensor quantification system for use in complex rural and urban environments
Authors: Collier-Oxandale Ashley , Casey Joanna Gordon , Piedrahita Ricardo , Ortega John , Halliday Hannah , Johnston Jill , Hannigan Michael P.
Published: June 2018

Abstract. Low-cost sensors have the potential to facilitate the exploration of air quality issues on new temporal and spatial scales. Here we evaluate a low-cost sensor quantification system for methane through its use in two different deployments. The first was a 1-month deployment along the Colorado Front Range and included sites near active oil and gas operations in the Denver-Julesburg basin. The second deployment was in an urban Los Angeles neighborhood, subject to complex mixtures of air pollution sources including oil operations. Given its role as a potent greenhouse gas, new low-cost methods for detecting and monitoring methane may aid in protecting human and environmental health. In this paper, we assess a number of linear calibration models used to convert raw sensor signals into ppm concentration values. We also examine different choices that can be made during calibration and data processing and explore cross sensitivities that impact this sensor type. The results illustrate the accuracy of the Figaro TGS 2600 sensor when methane is quantified from raw signals using the techniques described. The results also demonstrate the value of these tools for examining air quality trends and events on small spatial and temporal scales as well as their ability to characterize an area – highlighting their potential to provide preliminary data that can inform more targeted measurements or supplement existing monitoring networks.
Uncertainty analysis of total ozone derived from direct solar irradiance spectra in the presence of unknown spectral deviations
Authors: Vaskuri Anna , Kärhä Petri , Egli Luca , Gröbner Julian , Ikonen Erkki
Published: June 2018

Abstract. We demonstrate the use of a Monte Carlo model to estimate the uncertainties in total ozone column (TOC) derived from ground-based direct solar spectral
irradiance measurements. The model estimates the effects of possible
systematic spectral deviations in the solar irradiance spectra on the
uncertainties in retrieved TOC. The model is tested with spectral data
measured with three different spectroradiometers at an intercomparison
campaign of the research project “Traceability for atmospheric total column
ozone” at Izaña, Tenerife on 17 September 2016. The TOC values derived at
local noon have expanded uncertainties of 1.3 % (3.6 DU) for a high-end
scanning spectroradiometer, 1.5 % (4.4 DU) for a high-end array
spectroradiometer, and 4.7 % (13.3 DU) for a roughly adopted instrument based on commercially available components and an array spectroradiometer
when correlations are taken into account. When neglecting the effects of
systematic spectral deviations, the uncertainties reduce by a factor of 3.
The TOC results of all devices have good agreement with each other, within
the uncertainties, and with the reference values of the order of 282 DU
during the analysed day, measured with Brewer spectrophotometer #183.
The Advanced Infra-Red WAter Vapour Estimator (AIRWAVE) version 2: algorithm evolution, dataset description and performance improvements
Authors: Castelli Elisa , Papandrea Enzo , Di Roma Alessio , Dinelli Bianca Maria , Casadio Stefano , Bojkov Bojan
Published: June 2018

Abstract. The Total Column Water Vapour (TCWV) is a key atmospheric variable and its evaluation is generally performed, at global scale, through the use of satellite data. Recently a new algorithm, called AIRWAVE (Advanced Infra-Red Water Vapour Estimator), has been developed for the retrieval of the TCWV from the Along-Track Scanning Radiometer (ATSR) instrument series. The AIRWAVE algorithm performs the TCWV retrieval exploiting the dual view of the ATSR instruments using the infra-red channels at 10.8 and 12 μm and combining nadir and forward observation geometries. The algorithm was used to produce a TCWV database from the whole ATSR mission. When compared to independent TCWV products, AIRWAVE Version 1 (V1) database shows very good agreement with almost no bias all over the ATSR missions, with the exception of the polar and the costal region where AIRWAVE underestimate the TCWV amount. In this paper we describe an updated version of the algorithm, specifically developed to overcome these problems. The AIRWAVE Version 2 (V2) accounts for the atmospheric variability at different latitudes and the associated seasonality. In addition, the dependency of the retrieval parameters on satellite across-track viewing angles is now explicitly handled. With the new algorithm we produced a second version of the AIRWAVE dataset. As for V1, the quality of V2 dataset is assessed through the comparison with the Special Sensor Microwave/Imager (SSM/I) and with the Analyzed Radiosounding Archive (ARSA) TCWV data. Results show significant improvements in both biases and RMSE, especially in polar and costal regions. A qualitative and quantitative estimate of the main error sources affecting the V2 TCWV dataset is also given. The new dataset has also been used to estimate the water vapour climatology from the 1991–2012 time series.
The sensitivity of estuarine aragonite saturation state and pH to the carbonate chemistry of a freshet-dominated river
Authors: Moore-Maley Benjamin L. , Ianson Debby , Allen Susan E.
Published: June 2018

Abstract. Ocean acidification threatens to reduce pH and aragonite saturation state (ΩA) in estuaries, potentially damaging their ecosystems. However, the impact of highly variable river total alkalinity (TA) and dissolved inorganic carbon (DIC) on pH and ΩA in these estuaries is unknown. We assess the sensitivity of estuarine surface pH and ΩA to river TA and DIC using a coupled biogeochemical model of the Strait of Georgia on the Canadian Pacific coast and place the results in the context of global rivers. The productive Strait of Georgia estuary has a large, seasonally variable freshwater input from the glacially fed, undammed Fraser River. Analyzing TA observations from this river plume and pH from the river mouth, we find that the Fraser is moderately alkaline (TA 500–1000 µmol kg−1) but relatively DIC-rich. Model results show that estuarine pH and ΩA are sensitive to freshwater DIC and TA, but do not vary in synchrony except at high DIC : TA. The asynchrony occurs because increased freshwater TA is associated with increased DIC, which contributes to an increased estuarine DIC : TA and reduces pH, while the resulting higher carbonate ion concentration causes an increase in estuarine ΩA. When freshwater DIC : TA increases (beyond  ∼  1.1), the shifting chemistry causes a paucity of the carbonate ion that overwhelms the simple dilution/enhancement effect. At this high DIC : TA ratio, estuarine sensitivity to river chemistry increases overall. Furthermore, this increased sensitivity extends to reduced flow regimes that are expected in future. Modulating these negative impacts is the seasonal productivity in the estuary which draws down DIC and reduces the sensitivity of estuarine pH to increasing DIC during the summer season.
Vulnerability, resilience and adaptation of societies during major extreme storms during the Little Ice Age
Authors: Athimon Emmanuelle , Maanan Mohamed
Published: June 2018

Abstract. This manuscript reviews more than 19 691 French historical documents from 14 French archive centers. The results show that 101 extremes storms were recorded including 38 coastal floods. Coastal hazards have forced societies to adapt and develop some specific skills, lifestyles and coping strategies. By analysing the responses of past societies to these hazards, useful ideas may be (re)discovered by today's communities in order to enhance the ability to adapt and develop resilience. Similarly, a thorough knowledge of past climate hazards may allow our societies to recreate a link with territory, particularly through the (re)construction of an effective memory of these phenomena.
Numerical experiments on vapor diffusion in polar snow and firn and its impact on isotopes using the multi-layer energy balance model Crocus in SURFEX v8.0
Authors: Touzeau Alexandra , Landais Amaëlle , Morin Samuel , Arnaud Laurent , Picard Ghislain
Published: June 2018

Abstract. To evaluate the impact of vapor diffusion on isotopic
composition variations in snow pits and then in ice cores, we introduced
water isotopes in the detailed snowpack model Crocus. At each step and for
each snow layer, (1) the initial isotopic composition of vapor is taken at
equilibrium with the solid phase, (2) a kinetic fractionation is applied during
transport, and (3) vapor is condensed or snow is sublimated to compensate for
deviation to vapor pressure at saturation. We study the different effects of temperature gradient, compaction, wind
compaction, and precipitation on the final vertical isotopic profiles. We also
run complete simulations of vapor diffusion along isotopic gradients and of
vapor diffusion driven by temperature gradients at GRIP, Greenland and at
Dome C, Antarctica over periods of 1 or 10 years. The vapor diffusion tends
to smooth the original seasonal signal, with an attenuation of 7 to 12 %
of the original signal over 10 years at GRIP. This is smaller than the
observed attenuation in ice cores, indicating that the model attenuation due
to diffusion is underestimated or that other processes, such as ventilation,
influence attenuation. At Dome C, the attenuation is stronger (18 %),
probably because of the lower accumulation and stronger δ18O
gradients.
Analysis and validation of the PTVA tsunami building vulnerability model using the 2015 Chile post-tsunami damage data in Coquimbo and La Serena cities
Authors: Izquierdo Tatiana , Fritis Eduardo , Abad Manuel
Published: June 2018

Abstract. Chile is highly exposed to tsunami hazard from large
earthquakes often occurring along the Peru–Chile trench, like the
16 September 2015 event. However, only recently has tsunami hazard been
considered in the land-use policies of the Chilean coast. These new
regulations must enforce the identification of the most vulnerable sectors of
the Chilean coastal cities. This paper analyses and validates the two latest
versions of the Papathoma Tsunami Vulnerability Assessment (PTVA) model in
the 2015 tsunami reconstructed scenario in the cities of La Serena and
Coquimbo. Both models result in a similar number of very high and high
relative vulnerability index (RVI) scores. However, the less vulnerable
categories do not show a similar trend and the PTVA-4 model obtains a larger
number of minor and average RVI scores. When compared to the damages caused by
the tsunami, the PTVA-3 shows a more similar distribution to the actual
damages than that obtained by the PTVA-4 model, which shows a more concentrated
distribution of the RVI scores. These results suggest this version of the
model should be used in Chilean coastal cities in future land-use or
mitigation planning.
The seismogenic fault system of the 2017 Mw 7.3 Iran–Iraq earthquake: constraints from surface and subsurface data, cross-section balancing, and restoration
Authors: Tavani Stefano , Parente Mariano , Puzone Francesco , Corradetti Amerigo , Gharabeigli Gholamreza , Valinejad Mehdi , Morsalnejad Davoud , Mazzoli Stefano
Published: June 2018

Abstract. The 2017 Mw 7.3 Iran–Iraq earthquake occurred in a region where the pattern of major plate convergence is well constrained, but limited information is available on the seismogenic structures. Geological observations, interpretation of seismic reflection profiles, and well data are used in this paper to build a regional, balanced cross section that provides a comprehensive picture of the geometry and dimensional parameters of active faults in the hypocentral area. Our results indicate (i) the coexistence of thin- and thick-skinned thrusting, (ii) the reactivation of inherited structures, and (iii) the occurrence of weak units promoting heterogeneous deformation within the palaeo-Cenozoic sedimentary cover and partial decoupling from the underlying basement. According to our study, the main shock of the November 2017 seismic sequence is located within the basement, along the low-angle Mountain Front Fault. Aftershocks unzipped the up-dip portion of the same fault. This merges with a detachment level located at the base of the Paleozoic succession, to form a crustal-scale fault-bend anticline. Size and geometry of the Mountain Front Fault are consistent with a down-dip rupture width of 30 km, which is required for an Mw 7.3 earthquake.
Assessing the impact of acid rain and forest harvest intensity with the HD-MINTEQ model – Soil chemistry of three Swedish conifer sites from 1880 to 2080
Authors: McGivney Eric , Belyazid Salim , Zetterberg Therese , Löfgren Stefan , Gustafsson Jon Petter
Published: June 2018

Abstract. Forest soils are susceptible to anthropogenic acidification. In the past, acid rain was a major contributor to soil acidification, but now that atmospheric levels of S have dramatically declined, concern has shifted towards biomass-induced acidification, i.e., decreasing soil solution pH due to tree growth and harvesting events that permanently remove base cations (BC) from forest stands. We use a novel dynamic model, HD-MINTEQ, to investigate the long-term impacts of two theoretical future harvesting scenarios in the year 2020, a conventional harvest (CH, which removes stems only) and a whole-tree harvest (WTH, which removes 100 % of the above-ground biomass except for stumps), on soil chemistry and weathering rates at three different Swedish forest sites (Aneboda, Gårdsjön, and Kindla). Furthermore, acidification following the harvesting events is compared to the historical acidification that took place during the 20th century due to acid rain. Our results indicate that historical acidification due to acid rain had a larger impact on pore water chemistry and mineral weathering than tree growth and CH or WTH events, at least if nitrification remained at a low level. However, compared to a no-harvest scenario (NH), WTH and CH significantly impacted soil chemistry and weathering rates. Directly after a harvesting event (CH or WTH), the soil solution pH sharply increased for 5 to 10 years before slowly declining over the remainder of the simulation (until year 2080). WTH acidified soils slightly more than CH, with the largest effects being seen for the B1 horizons by the year 2080. Even though the pH values in the WTH and CH scenario decreased with time as compared to NH, they did not drop to the levels observed around the peak of historic acidification (1980–1990), indicating that the pH decrease due to tree growth and harvesting would be less impactful than that of historic atmospheric acidification. Weathering rates differed across locations and soil layers in response to historic acidification, but at several sites and layers, annual weathering rates decreased in tandem with decreasing pH, which is likely due to Al3+ weathering brakes. Weathering rates after the harvesting scenarios in 2020 generally increased although the dynamics were quite different depending on the site and soil layer.
Local topography increasingly influences the mass balance of a retreating cirque glacier
Authors: Florentine Caitlyn , Harper Joel , Fagre Daniel , Moore Johnnie , Peitzsch Erich
Published: June 2018

Abstract. Local topographically driven processes – such as wind drifting, avalanching,
and shading – are known to alter the relationship between the mass balance
of small cirque glaciers and regional climate. Yet partitioning such local
effects from regional climate influence has proven difficult, creating
uncertainty in the climate representativeness of some glaciers. We address
this problem for Sperry Glacier in Glacier National Park, USA, using
field-measured surface mass balance, geodetic constraints on mass balance,
and regional climate data recorded at a network of meteorological and snow
stations. Geodetically derived mass changes during 1950–1960, 1960–2005,
and 2005–2014 document average mass change rates during each period at
−0.22 ± 0.12, −0.18 ± 0.05, and
−0.10 ± 0.03 m w.e. yr−1, respectively. A correlation of field-measured mass balance and regional
climate variables closely (i.e., within 0.08 m w.e. yr−1) predicts
the geodetically measured mass loss from 2005 to 2014. However, this
correlation overestimates glacier mass balance for 1950–1960 by
+1.20 ± 0.95 m w.e. yr−1. Our analysis suggests that local
effects, not represented in regional climate variables, have become a more
dominant driver of the net mass balance as the glacier lost 0.50 km2
and retreated further into its cirque.
Effects of moisture absorption on damage progression and strength of unidirectional and cross-ply fiberglass–epoxy composites
Authors: Nunemaker Jake D. , Voth Michael M. , Miller David A. , Samborsky Daniel D. , Murdy Paul , Cairns Douglas S.
Published: June 2018

Abstract. Fiber-reinforced-polymer composites (FRPs) possess superior mechanical
properties and formability, making them a desirable material for construction
of large optimized mechanical structures, such as aircraft, wind turbines,
and marine hydrokinetic (MHK) devices. However, exposure to harsh marine
environments can result in moisture absorption into the microstructure of the
FRPs comprising these structures and often degrading mechanical properties.
Specifically, laminate static and fatigue strengths are often significantly
reduced, which must be considered in design of FRP structures in marine
environments. A study of fiberglass epoxy unidirectional and cross-ply
laminates was conducted to investigate hygrothermal effects on the mechanical
behavior of a common material system used in wind applications. Several
laminates were aged in 50 ∘C distilled water until maximum
saturation was reached. Unconditioned control and the saturated samples were
tested in quasi-static tension with the accompaniment of acoustic emission
(AE) monitoring. Cross-ply laminates experienced a 54 % reduction in
strength due to moisture absorption, while unidirectional laminate
strengths were reduced by 40 %. Stress–strain curves and AE activity of
the samples were analyzed to identify changes in damage progression due to
aging.
Facilitating and Supporting EdD Students’ Scholar Practitioner Writing as an Epistemological Tool
Authors: Fertman Carl I
Published: June 2018

Becoming adept at crafting scholarly writing is an important aspect of a doctoral student’s development.  Presented in this article is an EdD course, embedded writing scaffold that engages students and faculty to develop students’ scholarly inquiry projects.  That scaffold is the Applied Inquiry Plan (AIP).  The AIP creates a programmatic pathway to guide a Dissertation in Practice.  Working to improve the quality and value of scholar practitioner writing parallels and draws from efforts in the biomedical fields to develop writing guidelines that impact the quality and value of practice.  Creating and using the AIP provides opportunities for broad discussion of how to engage EdD students to view their writing as an epistemological tool.  Discussed is the AIP impact on EdD program redesign and improvement.