bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Search and Navigation User Experience by Making Use of Social Data
Authors: Cataldi Mario , Di Caro Luigi , Schifanella Claudio
Published: February 2018

Available user-generated content provides a huge opportunity to contextualize and improve search and navigational processes. Currently, the huge amount of available social data requires that new forms of personalized content indexing be oriented towards a more efficient reuse and retrieval of information. Based on these considerations, this chapter presents a new system that makes use of the social profile of the user, which is automatically extracted and modeled from social network platforms, to improve the search and navigation experience of the user. This proposed system dynamically defines the social context of the user in way that allows it to be positively used to improve his navigational experience. In this chapter, the authors provide a set of visualization tools that permits the user to be immersed in a user-dependent visual space that represented by a set of text boxes that are semantically related to the user query. These boxes represent possible context-aware refinement of the user search interest which are represented through different cohesive set of terms extracted from his social profile. Within this immersive system, at each step, users can deepen their searches by selecting a semantic box that best fits with their needs. This chapter also presents an evaluation aimed at testing the efficiency and the usability of the proposed system and provides real case scenarios and user studies that validate the proposed approach from the user point of view.
Researching Information Seeking in Digital Libraries Through Information-Seeking Models
Authors: Zaremohzzabieh Zeinab , Ahrari Seyedali , Abu Samah Bahaman , Bolong Jusang
Published: February 2018

There has been an increasing amount of research focus on the development of digital libraries, particularly on information seeking. A variety of information-seeking models used by library and information science (LIS) academics investigate the manner in which information is sought and transformed into knowledge, which should be taken into account during the design of digital libraries. However, in part this reflects the lack of knowledge about how these models explain user information seeking behaviors in a digital library environment. This chapter aims to address this lack of knowledge. It presents a set of information-seeking models that can be used by LIS scholars or experts to comprehend the dynamics of information seeking by users of digital libraries. The major role of this chapter is to provide a review of the existing “models” to date, and also to present a comparative analysis of the notable models that may contribute to ways of understanding the research on information seeking in digital libraries.
A Proposal to Study of Cross Language Information Retrieval (CLIR) System Users' Information Seeking Behavior
Authors: Ha YooJin
Published: February 2018

There has been an enormous increase for information written in different languages by users from various backgrounds and disciplines. This chapter proposes a research design to examine multilingual information users' information behaviors when using a Cross Language Information Retrieval (CLIR) system. Development of a true CLIR is absolutely necessary so that the system would allow users to access information written in the user's languages of choice. Kuhlthau's Information Search Process (ISP) model was borrowed as a theoretical framework. Of particular concern are those users who want information represented by a language different than the users' original query or for those users who would like to retrieve additional information written in a second and/or third language or in a language which cannot be understood by them. This research is expected to yield a revised or new ISP model applicable to CLIR environments. It is expected that this study will also increase our understanding of CLIR users. The expected CLIR users include many of non-English speakers, especially users in developing countries who need this kind of CLIR system due to lack of materials in their own language. It is possible that the results of this research could inform CLIR system designers. The chapter is composed of purpose of study, literature review, theory, research questions, methodology, and discussion section. In the literature review section, pertinent research studies from information seeking behavior, cross language information retrieval, and general relevance studies are presented. Kuhlthau's ISP model is introduced in detail in the theory section. A possible application of Kuhlthau's ISP Model to the CLIR environment is presented in a table format. Research questions are developed from the literature reviews and Kuhlthau's model. Each research question, premises/assumptions, and its correspondent methodology are proposed in the methodology section. Limitations are discussed in the discussion section.
Service-Driven Computing
Authors: Ramanathan Raja
Published: February 2018

Information technology is rapidly evolving to facilitate the design, development, and implementation of the next generation of architectural practices, tools, and techniques that will enable smart services and seamless enterprise integration. Service-Driven Computing involves the use of software services that conform to service architectural paradigms, such as Service-Oriented and Resource-Oriented Architectures, to drive computing solutions that enable building massively distributed software systems for this new generation of applications. Although services can promote agile, flexible, and extensible applications, service invocations can be subject to network latency, network failure, and distributed system failures. Moreover, service configurations are likely to change over time. This chapter explores the challenges in service-driven computing relating to composing adaptive services dynamically, supporting context-awareness and autonomic capabilities in services, verification of dynamic service compositions, and extending the service-driven paradigm to the Cloud. Along the way, contributions from researchers on potential solutions to these challenges are identified and discussed.
Challenges of Learning Analytics Execution in the Educational System
Authors: Singh Manoj Kumar
Published: February 2018

Education for the twenty-first century continues to promote discoveries in the field through learning analytics. The problem is that the rapid embrace of learning analytics diverts educators' attention from clearly identifying requirements and implications of using learning analytics in higher education. Learning analytics is a promising emerging field, yet higher education stakeholders need to become further familiar with issues related to the use of learning analytics in higher education. This chapter addresses the above problem and design of learning analytics implementations: the practical shaping of the human tactics involved in taking on and using analytic equipment, records, and reviews as part of an educational enterprise. This is an overwhelming but equally essential set of design choices from the ones made within the advent of the learning analytics structures themselves. Finally, this chapter's implications for learning analytics teachers and students and areas requiring further studies are highlighted.
Learning Analytics
Authors: Hayag Jr. Melquiades R.
Published: February 2018

Learning analytics has been focused on students and their contexts for functions of proficiency and optimizing learning and the environments in which it occurs. A description of the curriculum framework is accompanied by way of a discussion of the challenges to be handled as a part of this chapter. With greater than a million college and university students and thousands of instructors, the usage of the curriculum, a large and rich dataset, is continuously updated. This repository depicts teacher and students utilization and offers thrilling possibilities to leverage records to enhance coaching and studying. In this chapter, the author includes a studying analytics framework for designing curriculum.
A Framework for Evaluating Design Methodologies for Big Data Warehouses
Authors: Di Tria Francesco , Lefons Ezio , Tangorra Filippo
Published: February 2018

This article describes how the evaluation of modern data warehouses considers new solutions adopted for facing the radical changes caused by the necessity of reducing the storage volume, while increasing the velocity in multidimensional design and data elaboration, even in presence of unstructured data that are useful for providing qualitative information. The aim is to set up a framework for the evaluation of the physical and methodological characteristics of a data warehouse, realized by considering the factors that affect the data warehouse's lifecycle when taking into account the Big Data issues (Volume, Velocity, Variety, Value, and Veracity). The contribution is the definition of a set of criteria for classifying Big Data Warehouses on the basis of their methodological characteristics. Based on these criteria, the authors defined a set of metrics for measuring the quality of Big Data Warehouses in reference to the design specifications. They show through a case study how the proposed metrics are able to check the eligibility of methodologies falling in different classes in the Big Data context.
An Energy Efficient Trust Aware Opportunistic Routing Protocol for Wireless Sensor Network
Authors: Kumar Nagesh , Singh Yashwant , Singh Pradeep Kumar
Published: February 2018

As the wireless sensor networks (WSN) are gaining popularity the need of reliable delivery of data packets becomes more important. The reliable delivery is only possible when the routing protocols are efficient and secure. Because of lack of resources it is not possible to use existing cryptosystems to provide security in WSN. But, trust aware routing can provide the security with lesser resources, which become popular in last three to four years. In this paper, a new energy efficient and trust aware reliable opportunistic routing (TAEROR) protocol is proposed. The protocol consists of a trust metric and also a relay selection algorithm. The trust aware metric detects the malicious nodes on the basis of forwarding sincerity, energy consumption and acknowledgement sincerity. Relay selection algorithms avoid these malicious nodes to get selected in the routing process. The protocol is simulated and compared to existing trust aware routing protocols. Proposed protocol TEAROR presents better results than the other compared protocols.
A Survey on Using Nature Inspired Computing for Fatal Disease Diagnosis
Authors: Kaur Prableen , Sharma Manik
Published: February 2018

Genetic Algorithms (GA), Ant Colony Optimization (ACO), Particle Swarm Optimization (PSO) and Artificial Bee Colonies (ABC) are some vital nature inspired computing (NIC) techniques. These approaches have been used in early prophecy of various diseases. This article analyzes the efficacy of various NIC techniques in diagnosing diverse critical human disorders. It is observed that GA, ACO, PSO and ABC have been successfully used in early diagnosis of different diseases. As compared to ACO, PSO and ABC algorithms, GA has been extensively used in diagnosis of ecology, cardiology and endocrinologist. In addition, from the last six years of research, it has been observed that the accuracy accomplished using GA, ACO, PSO and ABC in the early diagnosis of cancer, diabetes and cardio problems lies between 73.5%-99.7%, 70%-99.2%, 80%-98% and 76.4% to 99.98% respectively. Furthermore, ACO, PSO and ABC are found to be best suited in diagnosing lung, prostate and breast cancer respectively. Moreover, the hybrid use of NIC techniques produces better results as compared to their individual use.
Mining Public Opinion about Economic Issues
Authors: Karami Amir , Bennett London S. , He Xiaoyun
Published: February 2018

Opinion polls have been the bridge between public opinion and politicians in elections. However, developing surveys to disclose people's feedback with respect to economic issues is limited, expensive, and time-consuming. In recent years, social media such as Twitter has enabled people to share their opinions regarding elections. Social media has provided a platform for collecting a large amount of social media data. This article proposes a computational public opinion mining approach to explore the discussion of economic issues in social media during an election. Current related studies use text mining methods independently for election analysis and election prediction; this research combines two text mining methods: sentiment analysis and topic modeling. The proposed approach has effectively been deployed on millions of tweets to analyze economic concerns of people during the 2012 US presidential election.
Tweeting Continuing Education
Authors: Panigrahi Ritanjali , Srivastava Praveen Ranjan
Published: February 2018

The rapid growth of technology has transformed education from conventional classroom teaching to learner centred, flexible learning anytime anywhere resulting in the popularity of Massive Open Online Courses (MOOCs). It is evident that many MOOCs have adopted social media tools to engage their learners through information sharing, participation, and collaboration to create and consume information. In addition to this, social media is the best place to understand crowd sentiments considering the massive amount of data being generated. This study through text mining of MOOC providers related Twitter data discovers the sentiments of users towards MOOCs, association rules, and the engagement of MOOC providers in Twitter. This article also analyses the traits of the influencers in seven MOOC providers and discovers that the influencers are popular users with higher numbers of followers count. The implications are discussed for MOOC industry, academic institutions, and the government.
Trends of Educational Informatics in Latin America
Authors: Gómez Adán A. , Caro Manuel F. , Solano Angela M. , Vega Yina M.
Published: February 2018

Educational Informatics is a multidisciplinary research area that uses Information and Communication Technology (ICT) in education. This article reports a wide overview about the new perspective of educational informatics that has been implemented in Latin America. This general view is the result of the different talks presented during the XIII Conference of Educational Informatics, organized by the Ibero-American Network of Educational Informatics RIBIE (Red Iberoamericana de Informática Educativa) in Colombia. These talks were proposed by international panelists from various parts of Latin America in the lines of ICT for Education and Peace, Thinking and Artificial Intelligence, Emergent Scenarios in Education and Mobiles Technologies and Apps for Entrepreneurship and Learning.
The Diffusion of Ignorance in On-Line Communities
Authors: Arfini Selene , Bertolotti Tommaso , Magnani Lorenzo
Published: February 2018

This article aims to investigate how information-sharing mechanisms in online communities favor activities of ignorance distribution on their platforms, such as fake data, biased beliefs, and inaccurate statements. In brief, the authors claim that online communities provide more ways to connect the users to one another rather than to control the quality of the data they share and receive. This, in turn, diminishes the value of fact-checking mechanisms in online news-consumption. The authors contend that while digital environments can stimulate the interest of groups of students and amateurs in scientific and political topics, the diffusion of false, poor, and un-validated data through digital media contributes to the formation of bubbles of shallow understanding in the digitally informed public. In brief, the present article is a philosophical research that applies the virtual niche construction theory to the cognitive behavior of internet users, as it is described by the current psychological, sociological, and anthropological literature.
Privacy Awareness and the Networking Generation
Authors: Odella Francesca
Published: February 2018

The article discusses the social and privacy implications of children's access to the internet and to information technologies of communication (ITCS) services. The growing rate of children online represents an epochal change for issues related to their personal safety and protection, as well as for their privacy rights and chances of improved life. In order to better understand the long term privacy implications of these phenomena the discussion reviews sociological studies that have investigated the structure of friendships networks among adolescents, and describes theoretical frames adopted in analysing social practices concerning the private sphere. Results of these studies provide clues on how interpersonal online relations are structured and how attitudes and practices circulate across and inside different social settings. Finally, implications for privacy issues related to the upcoming Internet of Things (IoT) are debated using the case of ethical design in engineering as an alternative option to the control option exercised by governments and companies.
The Relevance of Intellectual Capital in Shared Service Centres
Authors: Domingues Luisa , Pinto Agostinho Sousa , Guterres Carlos José
Published: February 2018

In the context of shared services, considering the intrinsic characteristics of the concepts service and sharing, organizational knowledge can assume different levels of relevance depending on the models adopted, from the most conventional to the most recent models considered as new forms of shared services. These are: Centres of Competence, Centres of Excellence, Centres of Expertise and Technical Centres. According to Nonaka, the creation of new knowledge takes place in a continuous process of transformation of tacit knowledge into explicit knowledge. Marciniak correlates the new models of shared services with the tacit and explicit knowledge. Domingues presents in the SSAM model the concept of intellectual capital as the driving force of innovation and quality service effectiveness. This article, using a qualitative approach and constructivist paradigm, develops exploratory research that aims in new directions and horizons at the confluence of these three models (Nonaka, SSAM and Marciniak) in knowledge management at shared service centres.
Letting the Patient Decide: A Case Report of Self-Administered Sedation During Mechanical Ventilation
Authors: Hetland Breanna , Hayes Sarah Maryon , Skaar Debra , Tracy Mary Fran , Weinert Craig R. , Chlan Linda
Published: February 2018

It is common for critical care nurses to administer sedative medications to patients receiving mechanical ventilation. Although patient-controlled analgesia is frequently used in practice to promote effective self-management of pain by patients, it is not known if patient-controlled sedation can be used to promote effective self-management of distressing symptoms associated with mechanical ventilation. A randomized pilot trial was conducted to evaluate whether patient self-administered sedation with dexmedetomidine is safe and acceptable for self-management of anxiety during ventilator support. This case report details the experiences of one patient enrolled in the pilot trial who was randomly assigned to the experimental dexmedetomidine intervention, completed the study protocol, and provided feedback. In a poststudy survey, the patient responded positively to the use of self-administered sedation with dexmedetomidine during ventilator support.
Antioxidant, anti-amylase and lipid lowering potential of leaves of Aporosa lindleyana Baill. (Kebella)
Authors: Kathirgamanathar S. , Abeysekera W. P. K. M. , Weerasinghe D. M. K. P. , Ranasinghe P. , Binduhewa A. M. C. U.
Published: February 2018

Globally, the demand for herbal products with antioxidant capacity is increased due to many health benefits. The approach to discover new drugs through natural products has become a successful strategy in recent years. Aporosa lindleyana Baill. (Kebella) is used as a leafy vegetable in Sri Lanka. Although the root and bark of this plant showed many biological activities, only antioxidant activity by DPPH mechanism and anti-inflammatory activity are reported in leaf. The present study investigated the antioxidants [Total Phenolic Content (TPC) and Total Flavonoid Content (TFC)], antioxidant activities [Ferric Reducing Antioxidant Power (FRAP),1,1-diphenyl-2-picrylhydrazyl radicalscavenging assay (DPPH),2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging assay (ABTS) and Oxygen Radical Absorbance Capacity (ORAC)], anti-amylase activity(using acarbosestandard)and anti-lipidaemicactivities via anti-lipase (AL), anti-cholesterolesterase (AC) and bile acids binding (BAB) invitro of 95% ethanolic extract (EE) and water extract (WE) of A.lindleyanaleaves along with its nutritional value.Both extracts showed significant differences (P<0.05) among the investigated antioxidants and antioxidant activities. For all the studied antioxidant activities, the EE showed high activity compared to WE and lower antioxidants in TPC. EE showed higher anti-amylase activity (IC50:164.85±8.36 μg/mL) compared to WE (IC50: 746.25±53.64 μg/mL). The IC50 of the standard drug, a carbose is 133.88 ± 4.4 μg/mL. Both extracts had dose dependant anti-lipidaemic activities in terms of anti-lipase, anti-cholesterol esterase and bile acids binding. However, EE showed significantly higher(p<0.05)anti-lipase and anti-cholesterol esterase activities compared to WE. In contrast, WE showed significantly higher (p<0.05) BAB for studied bile acids compared to EE (excepttaurocholate binding). Both extracts showed high taurocholate binding,similar binding of glycodeoxycholate and chenodeoxycholate and moderate anti-lipase activity compared to the reference drug (orlistat) studied.The proximate composition: moisture, carbohydrate, protein, crude fat, crude fibre and ash were 12.2, 49.4, 13.2, 1.1, 16.0 and 8.1%respectively. The minerals (Na, Mn, Fe, P, Zn, Cu: 53.7, 49.3, 41.4, 27.6, 22.6 and 10.4mg/kg; K, Ca and Mg: 18, 3.2and 2.7 g/kg, respectively) were also present. The leavesof A. lindleyana possess marked antioxidant, anti-amylase and moderate lipid lowering activities. This is the first report on multiple mechanisms of antioxidant activities, anti-amylase and lipid lowering effects which indicates the potential of developing A. lindleyana leaves as a functional food in prevention and management of non-communicable diseases.
Comparison of morphological and chemical characteristics of two selected accessions and six wild species of genus Cinnamomum Schaeff
Authors: Ariyarathne H. B. M. A. , Weerasuriya S. N. , Senarath W. T. P. S. K.
Published: February 2018

Cinnamon is increasingly becoming an important and potential foreign exchange earner and it is the most important spice in Sri Lanka. However, currently only two selected cinnamon accessions are available in Sri Lanka. Therefore, establishment of more commercial cinnamon varieties/ cultivars with high quality and yield are required. Experiments were carried out to investigate and compare of morphological and chemical characteristics of two selected cinnamon accessions (Sri Wijaya and Sri Gemunu) and six wild cinnamon species (Cinnamomum citriodorum, Cinnamomum capparu coronde, Cinnamomum litseaefolium, Cinnamomum revulorum, Cinnamomum dubium and Cinnamomum sinharajanse). Morphological characters of flower, leaf, seed and bark, yield of bark and leaf oil, and chemical characters of leaf and bark oil were examined. Leaf morphological characters; leaf shape, type of venation, leaf apex shape, leaf length and width, petiole length and leaf area were varied among species studied. Bark color, surface texture of bark, bark odor and seed color also helped to differentiate studied species. Highest mean leaf oil percentage and bark oil percentage was obtained from C. zeylanicum (Sri Gemunu) and C. zeylanicum (Sri Wijaya) respectively. The lowest mean leaf oil percentage was obtained from C. citriodorum and the lowest mean bark oil percentage was obtained from C. dubium. GC-MS analysis indicated presence of many economically important compounds such as eugenol, cinnamaldehyde, benzyl benzoate etc., in leaf and bark oil of all studied species. Abundance of considered favorable characters which are already consisted with cultivated accessions Sri Gemunu and Sri Wijaya bark and leaf oil with important characters and easy peeling ability has been observed in tested wild types, indicating the possibilities of improvement of Ceylon cinnamon for these characters through hybridization programme using wild relatives.
In vitro antioxidant and in vivo anti-inflammatory activity of Curcuma albiflora Thw.
Authors: Herath H. M. I. C. , Wijayasiriwardene T. D. C. M. K. , Premakumara G. A. S.
Published: February 2018

Curcuma albiflora Thw. is a poorly explored plant which is termed as Harankaha locally. Among other Harankaha plants, C. albiflora is threaten and restricted to Sabaragamuwa province only. Therefore, current study was conducted to quantify phytochemicals in terms of total phenolic content (TPC), total flavonoid content (TFC) and prove or disprove its antioxidant and anti-inflammatory activity using ferric reducing antioxidant power (FRAP), DPPH, ABTS+, and oxygen radical absorbance capacity (ORAC) assays, and carrageenan-induced paw oedema, formaldehyde-induced paw oedema, and cotton pellet induced granuloma tests in Wistar rats respectively. Whole plant extract from composite samples was prepared using 50% ethanol (in water) and 50% dichloromethane (in methanol) as solvents mixture by continuous extraction (6 h). Antioxidant values of TPC, TFC, and FRAP were 31.25 ± 1.48, 11.22 ± 0.13, and 17.90 ± 0.38 mg/g respectively. IC50 values (ppm) of DPPH and ABTS+ were 827.78 ± 6.06, and 188.84 ± 2.99 respectively. ORAC value was 128.10 ± 3.29 mg/g. The correlation of TFC was shown that it may link to flavonoid content. Since, C. albiflora inhibited (61% at 1h) 1st phase in the acute model, and at the late phase on sub-chronic model considering insignificant on cotton pellet granuloma test was shown that its anti-inflammatory activity (as 19.5% on 400 mg/kg) may not relate on prostaglandin. Further experiments are warrant to identify a mechanism of anti-inflammatory activity of C. albiflora.
Continuous multi-line queues and TASEP
Authors: Aas Erik , Linusson Svante
Published: February 2018

In this paper, we study a distribution

\Xi

of labeled particles on a continuous ring. It arises in three different ways, all related to the multi-type TASEP on a ring. We prove formulas for the probability density function for some permutations and give conjectures for a larger class. We give a complete conjecture for the probability of two particles

i, j

being next to each other on the cycle, for which we prove some cases. We also find that two natural events associated to the process have exactly the same probability expressed as a Vandermonde determinant. It is unclear whether this is just a coincidence or a consequence of a deeper connection.
Formal descriptions of Turaev's loop operations
Authors: Massuyeau Gwénaël
Published: February 2018

Using intersection and self-intersection of loops, Turaev introduced in the seventies two fundamental operations on the algebra

\mathbb Q[\pi]

of the fundamental group

\pi

of a surface with boundary. The first operation is binary and measures the intersection of two oriented based curves on the surface, while the second operation is unary and computes the self-intersection of an oriented based curve. It is already known that Turaev's intersection pairing has an algebraic description when the group algebra

\mathbb Q[\pi]

is completed with respect to powers of its augmentation ideal and is appropriately identified to the degree-completion of the tensor algebra

T(H)

of

H:=H_1(\pi;\mathbb Q)

.

In this paper, we obtain a similar algebraic description for Turaev's self-intersection map in the case of a disk with

p

punctures. Here we consider the identification between the completions of

\mathbb Q[\pi]

and

T(H)

that arises from a Drinfeld associator by embedding

\pi

into the pure braid group on

(p+1)

strands; our algebraic description involves a formal power series which is explicitly determined by the associator. The proof is based on some three-dimensional formulas for Turaev's loop operations, which involve

2

-strand pure braids and are shown for any surface with boundary.
Designing an Environmental Zone in a Mediterranean City to Support City Logistics
Authors: Ros-McDonnell Lorenzo , De-la-Fuente-Aragon María Victoria , Ros-McDonnell Diego , Cardós Carboneras Manuel
Published: February 2018

European cities are facing enormous challenges in accessibility and livability terms due to several European directives, which are compulsory in the mid/long term, traffic congestion levels are still increasing, and air pollution and noise disturbs citizens’ lives. This work presents the study carried out in a Mediterranean city to define an Environmental Zone with traffic restrictions for vehicles in the historical centre of the city of Cartagena (Spain) by exploring different urban logistics measures to tackle main problems caused by freight deliveries and pickups in the city centre. These solutions aimed to enhance the efficiency of vehicles, and to reduce both traffic congestion the environmental impacts caused by freight delivery in the city in order to improve urban sustainability.
Characterization of AVHRR global cloud detection sensitivity based on CALIPSO-CALIOP cloud optical thickness information: demonstration of results based on the CM SAF CLARA-A2 climate data record
Authors: Karlsson Karl-Göran , Håkansson Nina
Published: February 2018

Abstract. The sensitivity in detecting thin clouds of the cloud screening method being used in the CM SAF cloud, albedo and surface radiation data set from AVHRR data (CLARA-A2) cloud climate data record (CDR) has been evaluated using cloud information from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) onboard the CALIPSO satellite. The sensitivity, including its global variation, has been studied based on collocations of Advanced Very High Resolution Radiometer (AVHRR) and CALIOP measurements over a 10-year period (2006–2015). The cloud detection sensitivity has been defined as the minimum cloud optical thickness for which 50 % of clouds could be detected, with the global average sensitivity estimated to be 0.225. After using this value to reduce the CALIOP cloud mask (i.e. clouds with optical thickness below this threshold were interpreted as cloud-free cases), cloudiness results were found to be basically unbiased over most of the globe except over the polar regions where a considerable underestimation of cloudiness could be seen during the polar winter. The overall probability of detecting clouds in the polar winter could be as low as 50 % over the highest and coldest parts of Greenland and Antarctica, showing that a large fraction of optically thick clouds also remains undetected here. The study included an in-depth analysis of the probability of detecting a cloud as a function of the vertically integrated cloud optical thickness as well as of the cloud's geographical position. Best results were achieved over oceanic surfaces at mid- to high latitudes where at least 50 % of all clouds with an optical thickness down to a value of 0.075 were detected. Corresponding cloud detection sensitivities over land surfaces outside of the polar regions were generally larger than 0.2 with maximum values of approximately 0.5 over the Sahara and the Arabian Peninsula. For polar land surfaces the values were close to 1 or higher with maximum values of 4.5 for the parts with the highest altitudes over Greenland and Antarctica. It is suggested to quantify the detection performance of other CDRs in terms of a sensitivity threshold of cloud optical thickness, which can be estimated using active lidar observations. Validation results are proposed to be used in Cloud Feedback Model Intercomparison Project (CFMIP) Observation Simulation Package (COSP) simulators for cloud detection characterization of various cloud CDRs from passive imagery.
State updating and calibration period selection to improve dynamic monthly streamflow forecasts for an environmental flow management application
Authors: Gibbs Matthew S. , McInerney David , Humphrey Greer , Thyer Mark A. , Maier Holger R. , Dandy Graeme C. , Kavetski Dmitri
Published: February 2018

Abstract. Monthly to seasonal streamflow forecasts provide useful information for a
range of water resource management and planning applications. This work
focuses on improving such forecasts by considering the following two aspects:
(1) state updating to force the models to match observations from the start
of the forecast period, and (2) selection of a shorter calibration period
that is more representative of the forecast period, compared to a longer
calibration period traditionally used. The analysis is undertaken in the
context of using streamflow forecasts for environmental flow water management
of an open channel drainage network in southern Australia. Forecasts of
monthly streamflow are obtained using a conceptual rainfall–runoff model
combined with a post-processor error model for uncertainty analysis. This
model set-up is applied to two catchments, one with stronger evidence of
non-stationarity than the other. A range of metrics are used to assess
different aspects of predictive performance, including reliability,
sharpness, bias and accuracy. The results indicate that, for most scenarios
and metrics, state updating improves predictive performance for both observed
rainfall and forecast rainfall sources. Using the shorter calibration period
also improves predictive performance, particularly for the catchment with
stronger evidence of non-stationarity. The results highlight that a
traditional approach of using a long calibration period can degrade
predictive performance when there is evidence of non-stationarity. The
techniques presented can form the basis for operational monthly streamflow
forecasting systems and provide support for environmental decision-making.
Searching for the optimal drought index and timescale combination to detect drought: a case study from the lower Jinsha River basin, China
Authors: Fluixá-Sanmartín Javier , Pan Deng , Fischer Luzia , Orlowsky Boris , García-Hernández Javier , Jordan Frédéric , Haemmig Christoph , Zhang Fangwei , Xu Jijun
Published: February 2018

Abstract. Drought indices based on precipitation are commonly used to identify and characterize droughts. Due to the general complexity of droughts, the comparison of index-identified events with droughts at different levels of the complete system, including soil humidity or river discharges, relies typically on model simulations of the latter, entailing potentially significant uncertainties. The present study explores the potential of using precipitation-based indices to reproduce observed droughts in the lower part of the Jinsha River basin (JRB), proposing an innovative approach for a catchment-wide drought detection and characterization. Two indicators, namely the Overall Drought Extension (ODE) and the Overall Drought Indicator (ODI), have been defined. These indicators aim at identifying and characterizing drought events on the basin scale, using results from four meteorological drought indices (standardized precipitation index, SPI; rainfall anomaly index, RAI; percent of normal precipitation, PN; deciles, DEC) calculated at different locations of the basin and for different timescales. Collected historical information on drought events is used to contrast results obtained with the indicators. This method has been successfully applied to the lower Jinsha River basin in China, a region prone to frequent and severe droughts. Historical drought events that occurred from 1960 to 2014 have been compiled and cataloged from different sources, in a challenging process. The analysis of the indicators shows a good agreement with the recorded historical drought events on the basin scale. It has been found that the timescale that best reproduces observed events across all the indices is the 6-month timescale.
The length of coastlines in Ptolemy'sGeographyand in ancient periploi
Authors: Shcheglov Dmitry A.
Published: February 2018

Abstract. The lengths of the coastlines in Ptolemy's Geography are compared with the corresponding values transmitted by other ancient sources, presumably based on some lost periploi (literally "voyages around or circumnavigations", a genre of ancient geographical literature describing coastal itineraries). The comparison reveals a remarkable agreement between them, suggesting that Ptolemy relied much more heavily on these or similar periploi than it used to be thought. Additionally, a possible impact of Ptolemy's erroneous estimate of the circumference of the Earth is investigated. It is argued that this error resulted in two interrelated distortions of the coastal outlines in Ptolemy's Geography. First, the north–south stretches of the coast that were tied to particular latitudes are shown compressed relative to the distances recorded in other sources in roughly the same proportion to which Ptolemy's circumference of the Earth is underestimated relative to the true value. Second, in several cases this compression is compensated by a proportional stretching of the adjacent east–west coastal segments. In particular, these findings suggest a simple explanation for the strange shape of the Caspian Sea in Ptolemy's Geography.
South Atlantic meridional transports from NEMO-based simulations and reanalyses
Authors: Mignac Davi , Ferreira David , Haines Keith
Published: February 2018

Abstract. The meridional heat transport (MHT) of the South Atlantic plays a key role
in the global heat budget: it is the only equatorward basin-scale ocean heat
transport and it sets the northward direction of the global cross-equatorial
transport. Its strength and variability, however, are not well known. The
South Atlantic transports are evaluated for four state-of-the-art global
ocean reanalyses (ORAs) and two free-running models (FRMs) in the period
1997–2010. All products employ the Nucleus for European Modelling of the
Oceans (NEMO) model, and the ORAs share very similar configurations. Very few
previous works have looked at ocean circulation patterns in reanalysis
products, but here we show that the ORA basin interior transports are
consistently improved by the assimilated in situ and satellite observations
relative to the FRMs, especially in the Argo period. The ORAs also exhibit
systematically higher meridional transports than the FRMs, which is in closer
agreement with observational estimates at 35 and 11∘ S. However, the data
assimilation impact on the meridional transports still
greatly varies among the ORAs, leading to differences up to
∼ 8 Sv and 0.4 PW in the South Atlantic Meridional Overturning
Circulation and the MHTs, respectively. We narrow this down to large
inter-product discrepancies in the western boundary currents (WBCs) at both
upper and deep levels explaining up to ∼ 85 % of the
inter-product differences in MHT. We show that meridional velocity
differences, rather than temperature differences, in the WBCs drive
∼ 83 % of this MHT spread. These findings show that the
present ocean observation network and data assimilation schemes can be used
to consistently constrain the South Atlantic interior circulation but not
the overturning component, which is dominated by the narrow western boundary
currents. This will likely limit the effectiveness of ORA products for
climate or decadal prediction studies.
Water impacts and water-climate goal conflicts of local energy choices – notes from a Swedish perspective
Authors: Engström Rebecka Ericsdotter , Howells Mark , Destouni Georgia
Published: February 2018

Abstract. To meet both the Paris Agreement on Climate Change and the UN Sustainable
Development Goals (SDGs), nations, sectors, counties and cities need to move
towards a sustainable energy system in the next couple of decades. Such
energy system transformations will impact water resources to varying extents,
depending on the transformation strategy and fuel choices. Sweden is
considered to be one of the most advanced countries towards meeting the SDGs.
This paper explores the geographical origin of and the current water use
associated with the supply of energy in the 21 regional counties of Sweden.
These energy-related uses of water represent indirect, but still relevant,
impacts for water management and the related SDG on clean water and
sanitation (SDG 6). These indirect water impacts are here quantified and
compared to reported quantifications of direct local water use, as well as to
reported greenhouse gas (GHG) emissions, as one example of other types of
environmental impacts of local energy choices in each county. For each
county, an accounting model is set up based on data for the local energy use
in year 2010, and the specific geographical origins and water use associated
with these locally used energy carriers (fuels, heat and electricity) are
further estimated and mapped based on data reported in the literature and
open databases. Results show that most of the water use associated with the
local Swedish energy use occurs outside of Sweden. Counties with large shares
of liquid biofuel exhibit the largest associated indirect water use in
regions outside of Sweden. This indirect water use for energy supply does not
unambiguously correlate with either the local direct water use or the local
GHG emissions, although for the latter, there is a tendency towards an
inverse relation. Overall, the results imply that actions for mitigation of
climate change by local energy choices may significantly affect water
resources elsewhere. Swedish counties are thus important examples of
localities with large geographic zones of water influence due to their local
energy choices, which may compromise water security and the possibility to
meet water-related global goals in other world regions.
Modelling the impact of mulching the soil with plant remains on water regime formation, crop yield and energy costs in agricultural ecosystems
Authors: Gusev Yeugeniy M. , Dzhogan Larisa Y. , Nasonova Olga N.
Published: February 2018

Abstract. The model MULCH, developed by authors previously for simulating the formation of water regime in an agricultural field covered by straw mulch layer, has been used for the comparative evaluation of the efficiency of four agricultural cultivation technologies, which are usually used for wheat production in different regions of Russia and Ukraine. It simulates the dynamics of water budget components in a soil rooting zone at daily time step from the beginning of spring snowmelt to the beginning of the period with stable negative air temperatures. The model was designed for estimation of mulching efficiency in terms of increase in plant water supply and crop yield under climatic and soil conditions of the steppe and forest-steppe zones. It is used for studying the mulching effect on some characteristics of water regime and yield of winter wheat growing at specific sites located in semi-arid and arid regions of the steppe and forest-steppe zones of the eastern and southern parts of the East-European (Russian) plain. In addition, a previously developed technique for estimating the energetic efficiency of various agricultural technologies with accounting for their impact on changes in soil energy is applied for the comparative evaluation of the efficiency of four agricultural cultivation technologies, which are usually used for wheat production in different regions of the steppe and forest-steppe zones of the European Russia: (1) moldboard tillage of soil without irrigation, (2) moldboard tillage of soil with irrigation, (3) subsurface cultivation, and (4) subsurface cultivation with mulching the soil with plant remains.
The water–food–energy nexus in Pakistan: a biophysical and socio-economic challenge
Authors: Grigg Nicola , Foran Tira , Darbas Toni , Kirby Mac , Colloff Matthew J. , Ahmad Mobin-ud-Din , Podger Geoff
Published: February 2018

Abstract. We draw on previous work examining historical trends, likely future
water use and food availability in Pakistan and extend the analysis to
consider interactions with hydropower generation and the energy demand in
food production due to pumping of groundwater for irrigation.
Business-as-usual scenarios suggest growing demands for groundwater and
energy use for food production as population grows rapidly. However,
groundwater use is already unsustainable in many areas, and energy supply is
failing to keep up with demand. Quantifying material linkages between water,
food and energy provides a means to explore biophysical constraints.
Characterising institutional constraints is equally important, as they can be
significant barriers to effective stewardship of water, energy and food
resources. The experience in Pakistan reinforces this finding, and we discuss
the implications for hydrologists.
Potential impact of climate change to the future streamflow of Yellow River Basin based on CMIP5 data
Authors: Yang Xiaoli , Zheng Weifei , Ren Liliang , Zhang Mengru , Wang Yuqian , Liu Yi , Yuan Fei , Jiang Shanhu
Published: February 2018

Abstract. The Yellow River Basin (YRB) is the largest river basin in northern China,
which has suffering water scarcity and drought hazard for many years.
Therefore, assessments the potential impacts of climate change on the future
streamflow in this basin is very important for local policy and planning on
food security. In this study, based on the observations of 101 meteorological
stations in YRB, equidistant CDF matching (EDCDFm) statistical downscaling
approach was applied to eight climate models under two emissions scenarios
(RCP4.5 and RCP8.5) from phase five of the Coupled Model Intercomparison
Project (CMIP5). Variable infiltration capacity (VIC) model with
0.25∘ × 0.25∘ spatial resolution was developed based
on downscaled fields for simulating streamflow in the future period over YRB.
The results show that with the global warming trend, the annual streamflow
will reduced about 10 % during the period of 2021–2050, compared to the
base period of 1961–1990 in YRB. There should be suitable water resources
planning to meet the demands of growing populations and future climate
changing in this region.
Medium-range predictability of early summer sea ice thickness distribution in the East Siberian Sea: Importance of dynamical and thermodynamic melting processes
Authors: Nakanowatari Takuya , Inoue Jun , Sato Kazutoshi , Bertino Laurent , Xie Jiping , Matsueda Mio , Yamagami Akio , Sugimura Takeshi , Yabuki Hironori , Otsuka Natsuhiko
Published: February 2018

Abstract. Accelerated retreat of Arctic Ocean summertime sea ice has focused attention on the potential use of the Northern Sea Route (NSR), for which sea ice thickness (SIT) information is crucial for safe maritime navigation. This study evaluated the medium-range (lead time below 10 days) forecast skill of SIT distribution in the East Siberian Sea (ESS) in early summer (June–July) based on the TOPAZ4 ice ocean data assimilation system. Comparison of the operational model SIT data to all available observations (in situ and satellite) showed that the TOPAZ4 reanalysis reproduces the observed seasonal cycle and the rates of advance and melting of SIT in the ESS, with average bias of approximately ±20 cm. Pattern correlation analysis of the SIT forecast data over 4 years (2013–2016) reveals that the early summer SIT distribution is skillfully predicted for a lead time of up to 3 days, but that the prediction skill drops abruptly after the 4th day, which is related to dynamical process controlled by synoptic-scale atmospheric fluctuations. For longer lead times (> 4 days), the thermodynamic melting process takes over, which makes most of the remaining prediction skill. In July 2014, during which an ice-blocking incident occurred, relatively thick SIT (approximately 150 cm) was simulated over the ESS, which is consistent with the reduction of vessel speed. These results suggest that TOPAZ4 sea ice information has a great potential for practical applications in summertime maritime navigation via the NSR.