bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementation of ICT Strategic Plans in Public Organizations of Developing Countries
Authors: Gabriel Omari , Lupiana Dennis
Published: April 2018

This article describes how many public organizations today are embracing ICT; the use of ICT has become widespread in every aspect of the organizations' endeavors in supporting and evolving public service delivery. The widespread use of ICT has caused a serious reliance on ICT, which in this atmosphere involves business reengineering, change of organization culture which requires good management. ICT strategic plans as a managerial tool will rationalize ICT solutions and coordinate all efforts. It is noticed that public organizations in Tanzania are marginally use ICT; therefore, this article identifies internal control mechanisms and ICT challenges that affect ICT strategic plan implementation. Four public organizations were chosen and 24 respondents were interviewed from these organizations. Analysis of data showed both internal control mechanisms and ICT strategic plan executor capabilities affects ICT strategic plans implementation. Lastly, this article recommends public organizations to put in internal control mechanisms for successfully implementing ICT strategic plans as well as to address executor issues.
Automatic Text Document Summarization Using Graph Based Centrality Measures on Lexical Network
Authors: Yadav Chandra Shakhar , Sharan Aditi
Published: April 2018

This article proposes a new concept of Lexical Network for Automatic Text Document Summarization. Instead of a number of chains, the authors are getting a network of sentences which is called as Lexical Network termed as LexNetwork. This network is created between sentences based on different lexical and semantic relations. In this network, a node is representing sentences and edges are representing strength between two sentences. Strength means the number of relations present between the two sentences. The importance of the sentences is decided based on different centrality measures and extracted for the summary. WSD is done with Simple Lesk technique, and Cosine-Similarity threshold (Ɵ, TH) is used as post processing task. In this article, the authors are suggesting that a Cosine similarity threshold 10% is better vs. 5%, and an Eigen-Value based centrality measure is better for summarization process. At last for comparison, they are using Semantrica-Lexalytics System.
Data Visualization for Low-Frequency Inverse Synthetic Aperture Radar (ISAR)
Authors: Javidi Giti , Sheybani Ehsan
Published: April 2018

The purpose of this article was to use ISAR to determine the distance between the receiving antenna and the transmitting antenna. Once a systematic approach has been determined, this article could be used on a spacecraft to locate debris in the path of the carrier. Using low frequency radar that has the transmitting pulse built within the converters, the authors transmitted the data and determined the distance between the two antennas according to the time delay of the radar. Using amplified signals, the relationship between the distance and the time delay for the radar were calculated for each case. Additionally, these results were used to visualize in real-time the data transpired between the receiver and transmitter.
LDAP Vulnerability Detection in Web Applications
Authors: Shahriar Hossain , Haddad Hisham , Bulusu Pranahita
Published: April 2018

Lightweight Directory Access Protocol (LDAP) is commonly used in web applications to provide lookup information and enforcing authentication. Web applications may suffer from LDAP injection vulnerabilities that can lead to security breaches such as login bypass and privilege escalation. This paper1 proposes OCL fault injection-based detection of LDAP injection attacks. The authors extract design-level information and constraints expressed in OCL and then randomly alter them to generate test cases that have the capability to uncover LDAP injection vulnerabilities. The authors proposed approaches to implement test case generation, and they used one open source PHP application and one custom application to evaluate the proposed approach. The analysis shows that this approach can detect LDAP injection vulnerabilities.
An Empirical Investigation of Smartphone Adoption in Pakistan
Authors: Ikram Mohsin , Khan Sarah S. , Jeong Bong-Keun
Published: April 2018

Smartphone use has proliferated globally. However, there is a lack of understanding regarding the fast adoption of the technology at individual level, specifically for personal use. Technology adoption varies across geographic regions, and smartphone adoption is no exception. This article investigates smartphone adoption in Pakistan, which is one of the fastest growing smartphone markets. With the help from the Technology Acceptance Model (TAM), the authors build a research model by looking at the unique characteristics of the smartphone technology and Pakistan's market. The research model is empirically tested among 289 smartphone users. The results show perceived smartphone usefulness and the ease of use contributing significantly towards users' intention to adopt smartphone. Also, smartphone design, availability of smartphone applications, and social norms increases the smartphone use. However, technical difficulty in smartphone use negatively affects its adoption. The authors also discuss the implications and future research.
The Moderating Effect of Motivation to Comply and Perceived Critical Mass in Smartphones' Adoption
Authors: Illia Abdou , Lawson-Body Assion , Lee Simon , Akalin Gurkan I
Published: April 2018

The testing of the technology acceptance model over the years has shown that its explanatory power is about 50%; which led researchers to revisit the model in an attempt to gain a better understanding of technology adoption. Some of the studies found social influence to be a key factor, but others have yielded mixed results. This article questions the assumption made in some previous studies that most people would comply with social influence. Using data collected from 210 smartphone users, we investigated the moderating effect of motivation to comply on the relationship between social influence, on the one hand, and perceived usefulness and perceived ease-of-use on the other hand. Also, based on the theory of critical mass, we investigated the moderating effect of the perceived critical mass on the relationship between perceived usefulness and perceived ease of use on the one hand, and actual usage on the other hand. The results showed a significant moderating effect of both motivation to comply and perceived critical mass. Theoretical and practical implications are discussed.
Business-IT Alignment Literature Review
Authors: Jia Yu , Wang Nianxin , Ge Shilun
Published: April 2018

The purpose of this article is to portray the knowledge evolution paths of business-IT alignment (BITA) research and identify a set of important papers in the development of BITA, and elucidate the intellectual structure of this field. This study collected 309 papers published during the period 1983-2015 from the Web of Science (WOS) database. Using a variety of bibliometric and visualization analytic techniques such as citation analysis, co-citation analysis and main path analysis, this article (1) delineates the significant knowledge flows of BITA research and identifies 15 important papers in this field; (2) graphically maps the influential countries, institutions, and journals of BITA research; (3) identifies four major research themes: BITA model, measurement, antecedents, and dynamics, and visualizing the relationships among them. Based on these findings, recommendations for the future research directions have suggested. This article provides IT practitioners, executives, and scholars with a new perspective to get a better understanding of BITA.
Determinants of Repurchase Intention in C2C E-Commerce
Authors: Shihab Muhammad Rifki , Maulana Dimas , Hidayanto Achmad Nizar
Published: April 2018

In order to create a thriving c2c e-commerce environment, it is imperative for c2c e-commerce companies as well as merchants within to fully understand the factors that persuade existing customers to make repeat purchases. This article distinguishes itself by differentiating the roles of platform providers and those of merchants in identifying the determinants that affect repurchase intention in c2c e-commerce. Data in this article was collected from the users of a respected c2c e-commerce company in Indonesia. A total of 347 sample was analyzed using Partial Least Square (PLS), a variance based Structural Equation Modeling (SEM) aided by SmartPLS 2.0 software. The results of this article showed that satisfaction with merchants and trust in platform providers were factors that directly affected repurchase intention. Meanwhile, perceived quality of merchants, perceived quality of platform providers, perceived value, and trust in merchants were factors that affected repurchase intention indirectly.
Comparison of the Properties of Glasses Made from Two Different Bottom Ashes
Authors: Nonthathi Wanida , Auechalitanukul Chiraporn , McCuiston Ryan C.
Published: April 2018

Bottom ash is a waste byproduct generated from the combustion or incineration of materials such as coal and household waste. It is a mixed oxide powder of variable composition, though typically high in silica. As a low-cost, readily available material, it has found applications primarily in construction for use as backfill. As a silica-rich, mixed oxide powder though, it may also have glass forming ability. This research studied the possibility to use domestically produced bottom ash powder in glass making. Two bottom ash powders were used, one from a waste incinerator (Phuket) and the other from a coal-fired electric plant (Mae Moh Power Plant, Lampang). The bottom ash was milled into a fine powder and melted within the temperature range of 1300-1500 oC, for 2 hours. The melts were cast in a brass mold and then annealed at 500 oC for 2 hours. It was found that both bottom ashes could successfully produce glasses. The Vickers hardness, refractive index and specific gravity of the glasses will be discussed.
Effect of the Addition of ZrSiO4 on Alkali-Resistance and Liquidus Temperature of Basaltic Glass
Authors: Vaiborisut Napaporn , Chunwises Chanittha , Boonbundit Dararat , Jiemsirilers Sirithan , Theerapapvisetpong Apirat
Published: April 2018

Basalt fiber has been used as a reinforced material in cement-based materials because it has higher mechanical strength and cheaper than common silicate based glass-fibers. However, silicate-based glass fibers have low alkali resistance especially in cement matrix composite. In this work, we studied the improvement of alkali resistance by addition of zirconium silicate (ZrSiO4) in original basalt glass composition. The batch of basalt glass with additional ZrSiO4 contents of 0.00, 2.50, 5.00, 7.50 and 10.00 wt% were melted at 1500 °C. The liquidus temperature (TL) is important in for the fiber glass manufacturing. It need to formulate glass composition which requires a lower melting temperature and is crystallization resistant. TL as a function of composition is usually determined experimentally. In this study, glassy phase was determined by X-ray Diffraction (XRD). The glass transition temperature (Tg), the crystallization temperature (Tc) and TL were analyzed by Differential Thermal Analysis (DTA). The results found that the addition of ZrSiO4 in a basalt glass batch increased Tg while Tc of each sample was closed to original basalt fiber. Moreover, the alkali resistance of these glasses increased with an increasing of ZrSiO4 content. However, excessive ZrSiO4 contents (7.50 and 10.00 wt%) resulted in crystallization of ZrO2 which separated from glassy phase.
Phase Formation and Grain Growth of BSCZT Ceramics Prepared by BST-BZT Seed Induced Method
Authors: Dangsak Jiraporn , Eitssayeam Sukum , Sweatman Denis Russell , Intatha Uraiwan
Published: April 2018

In this work, lead-free Ba0.4Sr0.4Ca0.2Zr0.05Ti0.95O3 ceramics were prepared by the seed induced method using (0.5Ba0.6Sr0.4TiO3–0.5BaZr0.05Ti0.95O3) (BST-BZT) seed. Seed crystals with concentrations of 0, 2.5, 5, 7.5, 10 mol% were mixed with BSCZT powder for 24 h and sintered at 1400 °C for 4 h. The phase formation and microstructure of BSCZT ceramic were characterized by X-ray diffraction technique (XRD) and the scanning electron microscopy (SEM). All samples showed a single phase perovskite structure without impurities and exhibited the existence of the tetragonal phase. The density values of the ceramics decreased from 4.90 to 4.75 g/cm3 with increasing seed crystal concentrations. The grain size of the sample without seed was 3.71 μm, whereas a grain size of 8.99 μm was observed for the sample with 10 mol% seed crystal. The dielectric constant at room temperature at 1 kHz was 1831 for the sample with 10 mol% seed crystal while the dielectric constant of the sample without seed was 1484. From the results in this work, BST-BZT seed can increase grain size and improve the dielectric constant at room temperature.
Luminescence Property of Silicate Phosphor, Ba9Sc2Si6O24:Ce, Synthesized by Melt Quenching Technique
Authors: Toda Kenji , Tsuura Atsushi , Katsu Minenori , Kamei Shinnosuke , Ishigaki Tadashi , Uematsu Kazuyoshi , Sato Mineo
Published: April 2018

Well-grown Ba9Sc2Si6O24:Ce3+phosphors were synthesized by a novel melt quenching synthesis method. Sintered phosphor balls with excellent luminescent characteristics were obtained. This method is useful tool for rapid screening of phosphor materials.
Enhancing the Phase Conversion of Hydroxyapatite from Calcium Sulphate Hemihydrate by Hydrothermal Reaction
Authors: Pewkeaw Nuntiwat , Suwanprateeb Jintamai , Kashima Dujreutai Pongkao
Published: April 2018

Hydroxyapatite (HA) is a well-known biocompatible material which is widely used in orthopedic and dental applications. Because its chemical structure is similar to the human bone so it is compatible to use as a based materials in drug delivery system for treatment of bone infection diseases. In this research we focused on fabrication of HA sphere shape by three dimension printing using calcium sulphate hemihydrate (CaSO4·0.5H2O) as a starting material, then the as-three dimension printed CaSO4·0.5H2O spheres were hydrothermally treated in 1M disodium hydrogenphosphate (Na2HPO4) at 100°C-180°C for 2-8 hr. The reaction was taken place and the conversion of CaSO4·0.5H2O was gradually changed to Ca10(PO4)6(OH)2. Phase analysis by X-ray diffraction indicated that monetite (CaHPO4) was coexisted with HA when hydrothermally treated at pH 9 at low reaction temperature (<180°C). When the pH of 1M Na2HPO4 was adjusted to pH 11, 180°C for 6 hr, the as-three dimension printed calcium sulphate hemihydrate spheres were completely converted to HA spheres without any destruction of the sphere shape. This is confirmed that hydrothermal reaction could enhance the phase conversion of HA and the conversion time was four times faster than the normal conversion.
Designing Technique Transfer of Dan Kwian Pottery Products
Authors: Yeenang Chon , Kamon In Onlamee
Published: April 2018

The development of Dan Kwian pottery products is a research that uses participatory action research methodology and qualitative research method. By selecting a specific sampling in area 7, Dan Chai Community, Dan Kwian District, Muang, Nakhon Ratchasima Province, Thailand. The objective of this research three reasons: 1) the study form and evolution of Dan Kwian pottery products. 2) the development of Dan Kwian pottery products to form individually. 3) To study the satisfaction of entrepreneurs and consumers towards Dan Kwian pottery products. The research found that the model of Dan Kwian pottery products in the past to convey the wisdom of the grandparents emphasize the usefulness rather than beauty. At present, the style of Dan Kwien pottery products has been designed in a popular fashion and computer aided design. The pottery have a variety of uses and beauty than in the past. The Dan kwian pottery product was development pattern to form a new identity. The five models was selected: two cat models, one peacock model, one owl model and one cart model to from fifty models. The researcher was introduced five new pottery products to assess the satisfaction of four entrepreneurs and thirty consumers. It was found that the pattern of the pottery is unique has average of entrepreneurs was 4.75, while the consumer has average of 4.13. The uniqueness of skin color has average of entrepreneurs was 4.75, while the consumer has average of 4.00. The beauty of the new pottery has average of entrepreneurs was 5.00, while the consumer has average 4.27. The useful for function of the pottery has average of entrepreneurs was 5.00, while the consumer has average of 4.70.
Properties Alteration of Anti-Tuberculosis Drugs Loaded 3D Printed Hydroxyapatite by Polycaprolactone Coating
Authors: Suvannapruk Waraporn , Suwanprateeb Jintamai
Published: April 2018

Anti-tuberculosis drugs loaded three dimensionally printed hydroxyapatite (3D printed HA) were prepared and coated with polycaprolactone to study the effect of coating on compressive resistance, microstructure, drug content and releasing characteristics. Smooth coating layer was observed on the surfaces of all coated samples while the uncoated samples displayed rough and porous surfaces. Coated samples had greater compressive resistance than uncoated samples, but the total drug contents in coated samples were slightly lower than those of uncoated ones. Both coated and uncoated samples displayed burst release of drugs initially and followed by a small release afterward. Polycaprolactone coating greatly decrease the amount of burst release of rifampicin drug loaded samples, but slightly decrease in the case of isoniazid drug loaded samples. Higher solubility of isoniazid than rifampicin in release media was thought to be the cause of limited efficiency of coating as observed.
Development of Dengue Virus Serotype–Specific NS1 Capture Assays for the Rapid and Highly Sensitive Identification of the Infecting Serotype in Human Sera
Authors: Röltgen Katharina , Rose Natalie , Ruggieri Alessia , Warryn Louisa , Scherr Nicole , Pinho-Nascimento Carlos Augusto , Tamborrini Marco , Jaenisch Thomas , Pluschke Gerd
Published: April 2018

Dengue fever can be caused by one of four distinct dengue virus (DENV) serotypes that cocirculate in many parts of the world. Point of care serotype-specific nonstructural protein-1 (NS1) capture assays for the rapid serotyping of DENV in human sera would greatly support epidemiological surveillance and potentially also prognosis in individual patients. To ensure both serotype specificity and broad coverage of variants within serotypes, we have applied an innovative approach for the generation and selection of serotype-specific anti-NS1 mAbs. To elicit mAbs against conformational epitopes, NMRI mice were immunized with living HEK 293 transfectants expressing the native target Ags in multiple display on the cell surface. For each serotype, three different NS1 sequence variants were sequentially used for immunization of mice, hybridoma selection, and capture assay development, respectively. Selection of optimal combinations of capturing and detecting mAbs yielded highly sensitive and specific NS1 serotyping ELISAs (st-ELISAs) for the four serotypes. st-ELISA testing of 41 dengue patient sera showed a 100% concordance with the serotype determined by serotype-specific reverse transcriptase real-time quantitative PCR. The respective NS1 variants could be detected for ∼10 d after the onset of illness. Ab-dependent enhancement of DENV infections may be associated with a specific range of pre-existing anti-DENV serological Ab titers. Testing of patient sera with the developed st-ELISAs will not only be useful for epidemiological studies and surveillance, but it may also help to develop and validate assays that can distinguish protective versus enhancing Ab responses for risk assessment for the development of severe dengue disease in individual patients.
Biochemical changes in diabetic retinopathy triggered by hyperglycaemia: A review
Authors: Mathebula Solani D.
Published: April 2018

Background: Diabetes mellitus (DM) is now a global health problem which will lead to increasing incidence of macrovascular and microvascular complications that contribute to morbidity, mortality and premature deaths. Diabetic retinopathy (DR) is a serious complication of DM, and its prevalence is increasing worldwide. Diabetes mellitus is one of the fastest growing causes of visual impairment and blindness in the working-age population.Aim: The aim of this paper was to introduce the multiple interconnecting biochemical pathways that have been proposed and tested as key contributors in how the diabetic eye loses vision.Method: An extensive literature search was performed using the Medline database from 1970 to present. The search subjects included diabetes and eye, diabetic retinopathy and diabetic complications in the eye. The search was limited to the literature pertaining to humans and to English language. Preference was given to recent published papers.Results: Results were limited to human participants with publications in English. References of all included papers were also scrutinized to identify additional studies. Studies were selected for inclusion in the review if they met the following criteria: subjects with diabetes, pathophysiology of diabetic retinopathy.Conclusion: Although the biochemical pathways involved in DR have been researched, to date the exact mechanism involved in the onset and progression of the disease is uncertain, which makes therapeutic interventions challenging. The aim of this review is to discuss the possible biochemical pathways and clinical and anatomical changes that occur during the onset and progression of DR that link hyperglycaemia with retinal tissue damage. An understanding of the biochemical and molecular changes may lead to health care practitioners advising patients with DR on events that lead to possible complications of the diseases.
Characterizations of the Ricci flow
Authors: Haslhofer Robert , Naber Aaron
Published: April 2018

This is the first of a series of papers, where we introduce a new class of estimates for the Ricci flow, and use them both to characterize solutions of the Ricci flow and to provide a notion of weak solutions to the Ricci flow in the nonsmooth setting. In this first paper, we prove various new estimates for the Ricci flow, and show that they in fact characterize solutions of the Ricci flow. Namely, given a family

(M,g_t)_{t \in I}

of Riemannian manifolds, we consider the path space

P\mathcal{M}

of its space time

\mathcal{M}=M\times I

. Our first characterization says that

(M,g_t)_{t \in I}

evolves by Ricci flow if and only if an infinite dimensional gradient estimate holds for all functions on

P\mathcal{M}

. We prove additional characterizations in terms of the

C^{1/2}

-regularity of martingales on path space, as well as characterizations in terms of log-Sobolev and spectral gap inequalities for a family of Ornstein–Uhlenbeck type operators. Our estimates are infinite-dimensional generalizations of much more elementary estimates for the linear heat equation on

(M,g_t)_{t \in I}

, which themselves generalize the Bakry–Émery–Ledoux estimates for spaces with lower Ricci curvature bounds. Thanks to our characterizations we can define a notion of weak solutions for the Ricci flow. We will develop the structure theory of these weak solutions in subsequent papers.
15 Pole Connector Between Towing Vehicles and Trailers with 12 Volt Nominal Supply
Authors:   Truck and Bus Electrical Systems Committee
Published: April 2018

This SAE standard establishes the minimum construction and performance requirements for a 15 Pole Connector Between Towing Vehicles and Trailers, for trucks, trailers, and dollies in conjunction with SAE J2742. The connector accommodates both power and ISO 11992-1 signal circuits along with dual ground wires to accommodate grounding requirements within the constraints of the SAE J2691 terminal capacity.
Infancias Ignoradas. Hijos e Hijas de Mujeres Víctimas de Violencia en situación de Refugio
Authors: Carrillo Meráz Rosalia , Jiménez Bernal Graciela
Published: April 2018

En México, en la década de 1990 se crean los primeros refugios para mujeres víctimas de violencia con el fin de atenderlas y darles un lugar donde vivir al momento de huir de su agresor. Se diseñaron estrategias para atenderlas de manera integral pero, en un inicio no se pensó en sus hijos e hijas, quienes llegaban con ellas al refugio y sólo se les entretenía mientras psicólogas y trabajadoras sociales atendían a sus madres. Ahora, ante la necesidad de proteger a la comunidad infantil en situación de refugio, empiezan a diseñarse estrategias para dar seguimiento y atención a estos menores que antes eran ignorados como víctimas.
La mayoría de edad como requisito para la rectificación registral del sexo y el nombre: una cuestión de derechos fundamentales
Authors: Sánchez Freyre Juan Manuel
Published: April 2018

Trascendencia constitucional de la exigencia de mayoría de edad para el reconocimiento del derecho a la identidad sexual y al cambio en la mención registral del sexo en el Registro Civil en el caso de las personas transexuales y su incardinación en las limitaciones a la capacidad de obrar de las menores de edad. Diversidad de tratamiento jurídico de la edad y su tratamiento legislativo y jurisprudencial en atención a la progresiva adquisición de discernimiento y capacidad de entender y emitir su voluntad de las personas en su minoría de edad legal. El principio de interés superior de la persona menor de edad como marco referencial para analizar cada caso concreto en defensa de los derechos fundamentales en general y su concreción en la niñez y adolescencia. La dificultad de la valoración de este concepto jurídico indeterminado.
Measurements of atmospheric ethene by solar absorption FTIR spectrometry
Authors: Toon Geoffrey C. , Blavier Jean-Francois L. , Sung Keeyoon
Published: April 2018

Abstract. Atmospheric ethene (C2H4; ethylene) amounts have been retrieved
from high-resolution solar absorption spectra measured by the Jet Propulsion
Laboratory (JPL) MkIV interferometer. Data recorded from 1985 to 2016 from a
dozen ground-based sites have been analyzed, mostly between 30 and
67∘ N. At clean-air sites such as Alaska, Sweden, New Mexico, or the
mountains of California, the ethene columns were always less than
1 × 1015 molec cm−2 and therefore undetectable. In urban
sites such as JPL, California, ethene was measurable with column amounts of
20 × 1015 molec cm−2 observed in the 1990s. Despite the
increasing population and traffic in southern California, a factor 3 decrease
in ethene column density is observed over JPL over the past 25 years,
accompanied by a decrease in CO. This is likely due to southern California's
increasingly stringent vehicle exhaust regulations and tighter enforcement
over this period.
Insights into the diurnal cycle of global Earth outgoing radiation using a numerical weather prediction model
Authors: Gristey Jake J. , Chiu J. Christine , Gurney Robert J. , Morcrette Cyril J. , Hill Peter G. , Russell Jacqueline E. , Brindley Helen E.
Published: April 2018

Abstract. A globally complete, high temporal resolution and multiple-variable
approach is employed to analyse the diurnal cycle of Earth's
outgoing energy flows. This is made possible via the use of Met
Office model output for September 2010 that is assessed alongside
regional satellite observations throughout. Principal component
analysis applied to the long-wave component of modelled outgoing
radiation reveals dominant diurnal patterns related to land surface
heating and convective cloud development, respectively explaining
68.5 and 16.0 % of the variance at the global scale. The total
variance explained by these first two patterns is markedly less than
previous regional estimates from observations, and this analysis
suggests that around half of the difference relates to the lack of
global coverage in the observations. The first pattern is strongly
and simultaneously coupled to the land surface temperature diurnal
variations. The second pattern is strongly coupled to the cloud
water content and height diurnal variations, but lags the cloud
variations by several hours. We suggest that the mechanism
controlling the delay is a moistening of the upper troposphere due
to the evaporation of anvil cloud. The short-wave component of
modelled outgoing radiation, analysed in terms of albedo, exhibits
a very dominant pattern explaining 88.4 % of the variance that
is related to the angle of incoming solar radiation, and a second
pattern explaining 6.7 % of the variance that is related to
compensating effects from convective cloud development and marine
stratocumulus cloud dissipation. Similar patterns are found in
regional satellite observations, but with slightly different timings
due to known model biases. The first pattern is controlled by
changes in surface and cloud albedo, and Rayleigh and aerosol
scattering. The second pattern is strongly coupled to the diurnal
variations in both cloud water content and height in convective
regions but only cloud water content in marine stratocumulus
regions, with substantially shorter lag times compared with the
long-wave counterpart. This indicates that the short-wave radiation
response to diurnal cloud development and dissipation is more rapid,
which is found to be robust in the regional satellite
observations. These global, diurnal radiation patterns and their
coupling with other geophysical variables demonstrate the process-level understanding that can be gained using this approach and
highlight a need for global, diurnal observing systems for Earth
outgoing radiation in the future.
Response of stratospheric water vapor and ozone to the unusual
timing of El Niño and QBO disruption in 2015–2016
Authors: Diallo Mohamadou , Riese Martin , Birner Thomas , Konopka Paul , Müller Rolf , Hegglin Michaela I. , Santee Michelle L. , Baldwin Mark , Legras Bernard , Ploeger Felix
Published: April 2018

Abstract. The stratospheric circulation determines the transport and lifetime of key greenhouse gases, including water vapor and ozone, which radiatively impact surface climate. The unusually warm El Niño Southern Oscillation (ENSO) event aligned with a disrupted Quasi-Biennial Oscillation (QBO) caused an unprecedented perturbation to this circulation in 2015–2016. Here, we quantify the impact of the alignment of these two phenomena in 2015–2016 on lower stratospheric water vapor and ozone from satellite observations. We show that the warm ENSO event substantially increases water vapor and decreases ozone in the tropical lower stratosphere. The QBO disruption significantly decreases global lower stratospheric water vapor and tropical ozone from early spring to late autumn. Thus, this QBO disruption reverses the lower stratosphere moistening triggered by the alignment of the warm ENSO event with westerly QBO in early boreal winter. Our results suggest that the interplay of ENSO events and QBO phases will be crucial for the distributions of radiatively active greenhouse gases in a changing future climate, when increasing El Niño-like conditions and decreasing lower stratospheric QBO amplitude are expected.
Computational efficiency for the surface renewal method
Authors: Kelley Jason , Higgins Chad
Published: April 2018

Abstract. Measuring surface fluxes using the surface renewal (SR) method requires
programmatic algorithms for tabulation, algebraic calculation, and data
quality control. A number of different methods have been published describing
automated calibration of SR parameters. Because the SR method utilizes high-frequency (10 Hz+) measurements, some steps in the flux calculation are
computationally expensive, especially when automating SR to perform many
iterations of these calculations. Several new algorithms were written that
perform the required calculations more efficiently and rapidly, and that tested
for sensitivity to length of flux averaging period, ability to measure over a
large range of lag timescales, and overall computational efficiency.
These algorithms utilize signal processing techniques and algebraic
simplifications that demonstrate simple modifications that dramatically
improve computational efficiency. The results here complement efforts by
other authors to standardize a robust and accurate computational SR method.
Increased speed of computation time grants flexibility to implementing the SR
method, opening new avenues for SR to be used in research, for applied
monitoring, and in novel field deployments.
Quantification of peroxynitric acid and peroxyacyl nitrates using an ethane-based thermal dissociation peroxy radical chemical amplification cavity ring-down spectrometer
Authors: Taha Youssef M. , Saowapon Matthew T. , Assad Faisal V. , Ye Connie Z. , Chen Xining , Garner Natasha M. , Osthoff Hans D.
Published: April 2018

Abstract. Peroxy and peroxyacyl nitrates (PNs and PANs) are important trace gas constituents of the troposphere which are challenging to quantify by differential thermal dissociation with NO2 detection in polluted (i.e., high-NOx) environments. In this paper, a thermal dissociation peroxy radical chemical amplification cavity ring-down spectrometer (TD-PERCA-CRDS) for sensitive and selective quantification of total peroxynitrates (ΣPN = ΣRO2NO2) and of total peroxyacyl nitrates (ΣPAN = ΣRC(O)O2NO2) is described. The instrument features multiple detection channels to monitor the NO2 background and the ROx (= HO2 + RO2 + ΣRO2) radicals generated by TD of ΣPN and/or ΣPAN. Chemical amplification is achieved through addition of 0.6 ppm NO and 1.6 % C2H6 to the inlet. The instrument's performance was evaluated using peroxynitric acid (PNA) and peroxyacetic or peroxypropionic nitric anhydride (PAN or PPN) as representative examples of ΣPN and ΣPAN, respectively, whose abundances were verified by iodide chemical ionization mass spectrometry (CIMS). The amplification factor or chain length increases with temperature up to 69 ± 5 and decreases with analyte concentration and relative humidity (RH). At inlet temperatures above 120 °C and 250 °C, respectively, PNA and ΣPAN fully dissociated, though their TD profiles partially overlap. Furthermore, interference from ozone (O3) was observed at temperatures above 150 °C, rationalized by its partial dissociation to O atoms which react with C2H6 to form C2H5 and OH radicals. Quantification of PNA and ΣPAN in laboratory-generated mixtures containing O3 was achieved by simultaneously monitoring the TD-PERCA responses in multiple parallel CRDS channels set to different temperatures in the 60 °C to 130 °C range. The (1 s, 1σ) limit of detection (LOD) of TD-PERCA-CRDS is 3.4 pptv for PNA and 1.3 pptv for ΣPAN and significantly lower than TD-CRDS without chemical amplification. The feasibility of TD-PERCA-CRDS for ambient air measurements is discussed.
Midlatitude atmospheric circulation responses under 1.5 and 2.0 °C warming and implications for regional impacts
Authors: Li Camille , Michel Clio , Seland Graff Lise , Bethke Ingo , Zappa Giuseppe , Bracegirdle Thomas J. , Fischer Erich , Harvey Ben J. , Iversen Trond , King Martin P. , Krishnan Harinarayan , Lierhammer Ludwig , Mitchell Daniel , Scinocca John , Shiogama Hideo , Stone Dáithí A. , Wettstein Justin J.
Published: April 2018

Abstract. This study investigates the global response of the midlatitude atmospheric circulation to 1.5 and 2.0 °C of warming using the HAPPI (Half a degree Additional warming, Prognosis and Projected Impacts) ensemble, with a focus on the winter season. Characterising and understanding this response is critical for accurately assessing the near-term regional impacts of climate change and the benefits of limiting warming to 1.5 °C above pre-industrial levels, as advocated by the Paris Agreement of the United Nations Framework Convention on Climate Change (UNFCCC). The HAPPI experimental design allows an assessment of uncertainty in the circulation response due to model dependence and internal variability. Internal variability is found to dominate the multi-model mean response of the jet streams, storm tracks, and stationary waves across most of the midlatitudes; larger signals in these features are mostly consistent with those seen in more strongly forced warming scenarios. Signals that emerge in the 1.5 °C experiment are a weakening of storm activity over North America, an inland shift of the North American stationary ridge, an equatorward shift of the North Pacific jet exit, and an equatorward intensification of the South Pacific jet. Signals that emerge under an additional 0.5 °C of warming include a poleward shift of the North Atlantic jet exit, an eastward extension of the North Atlantic storm track, and an intensification on the flanks of the Southern Hemisphere storm track. Case studies explore the implications of these circulation responses for precipitation impacts in the Mediterranean, in western Europe, and on the North American west coast, paying particular attention to possible outcomes at the tails of the response distributions. For example, the projected weakening of the Mediterranean storm track emerges in the 2 °C warmer world, with exceptionally dry decades becoming 5 times more likely.
Ecological landscape elements: long-term monitoring in Great Britain, the Countryside Survey 1978–2007 and beyond
Authors: Wood Claire M. , Bunce Robert G. H. , Norton Lisa R. , Maskell Lindsay C. , Smart Simon M. , Scott W. Andrew , Henrys Peter A. , Howard David C. , Wright Simon M. , Brown Michael J. , Scott Rod J. , Stuart Rick C. , Watkins John W.
Published: April 2018

Abstract. The Countryside Survey (CS) of Great Britain (GB) provides a unique and statistically robust series of datasets, consisting of an extensive set of repeated ecological measurements at a national scale, covering a time span of 29 years. CS was first undertaken in 1978 to provide a baseline for ecological and land use change monitoring in the rural environment of GB, following a stratified random design, based on 1 km squares. Originally, eight random 1 km squares were drawn from each of 32 environmental classes, thus comprising 256 sample squares in the 1978 survey. The number of these sites increased to 382 in 1984, 506 in 1990, 569 in 1998 and 591 in 2007. Detailed information regarding vegetation types and land use was mapped in all five surveys, allowing reporting by defined standard habitat classifications. Additionally, point and linear landscape features (such as trees and hedgerows) are available from all surveys after 1978. From these stratified, randomly located sample squares, information can be converted into national estimates, with associated error terms. Other data, relating to soils, freshwater and vegetation, were also sampled on analogous dates. However, the present paper describes only the surveys of landscape features and habitats. The resulting datasets provide a unique, comprehensive, quantitative ecological coverage of extent and change in these features in GB. Basic results are presented and their implications discussed. However, much opportunity for further analyses remains. Data from each of the survey years are available via the following DOIs: Landscape area data 1978: https://doi.org/10.5285/86c017ba-dc62-46f0-ad13-c862bf31740e, 1984: https://doi.org/10.5285/b656bb43-448d-4b2c-aade-7993aa243ea3, 1990: https://doi.org/10.5285/94f664e5-10f2-4655-bfe6-44d745f5dca7, 1998: https://doi.org/10.5285/1e050028-5c55-42f4-a0ea-c895d827b824, and 2007: https://doi.org/10.5285/bf189c57-61eb-4339-a7b3-d2e81fdde28d; Landscape linear feature data 1984: https://doi.org/10.5285/a3f5665c-94b2-4c46-909e-a98be97857e5, 1990: https://doi.org/10.5285/311daad4-bc8c-485a-bc8a-e0d054889219, 1998: https://doi.org/10.5285/8aaf6f8c-c245-46bb-8a2a-f0db012b2643 and 2007: https://doi.org/10.5285/e1d31245-4c0a-4dee-b36c-b23f1a697f88, Landscape point feature data 1984: https://doi.org/10.5285/124b872e-036e-4dd3-8316-476b5f42c16e, 1990: https://doi.org/10.5285/1481bc63-80d7-4d18-bcba-8804aa0a9e1b, 1998: https://doi.org/10.5285/ed10944f-40c8-4913-b3f5-13c8e844e153 and 2007: https://doi.org/10.5285/55dc5fd7-d3f7-4440-b8a7-7187f8b0550b.
Examining controls on peak annual streamflow and floods in the Fraser River Basin of British Columbia
Authors: Curry Charles L. , Zwiers Francis W.
Published: April 2018

Abstract. The Fraser River Basin (FRB) of British Columbia is one of the largest and
most important watersheds in western North America, and home to a rich
diversity of biological species and economic assets that depend implicitly
upon its extensive riverine habitats. The hydrology of the FRB is dominated
by snow accumulation and melt processes, leading to a prominent annual peak
streamflow invariably occurring in May–July. Nevertheless, while annual peak
daily streamflow (APF) during the spring freshet in the FRB is historically
well correlated with basin-averaged, 1 April snow water equivalent (SWE),
there are numerous occurrences of anomalously large APF in below- or
near-normal SWE years, some of which have resulted in damaging floods in the
region. An imperfect understanding of which other climatic factors contribute
to these anomalously large APFs hinders robust projections of their magnitude
and frequency. We employ the Variable Infiltration Capacity (VIC) process-based hydrological
model driven by gridded observations to investigate the key controlling
factors of anomalous APF events in the FRB and four of its subbasins that
contribute nearly 70 % of the annual flow at Fraser-Hope. The relative
influence of a set of predictors characterizing the interannual variability
of rainfall, snowfall, snowpack (characterized by the annual maximum value,
SWEmax), soil moisture and temperature on simulated APF at Hope
(the main outlet of the FRB) and at the subbasin outlets is examined within a
regression framework. The influence of large-scale climate modes of
variability (the Pacific Decadal Oscillation (PDO) and the
El Niño–Southern Oscillation – ENSO) on APF magnitude is also assessed,
and placed in context with these more localized controls. The results
indicate that next to SWEmax (univariate Spearman correlation
with APF of ρ^ = 0.64; 0.70 (observations; VIC simulation)),
the snowmelt rate (ρ^ = 0.43 in VIC), the ENSO and PDO indices
(ρ^ = −0.40; −0.41) and (ρ^ = −0.35;
−0.38), respectively, and rate of warming subsequent to the date of
SWEmax (ρ^ = 0.26; 0.38), are the most influential
predictors of APF magnitude in the FRB and its subbasins. The identification
of these controls on annual peak flows in the region may be of use in
understanding seasonal predictions or future projected streamflow changes.
Enhancing flood hazard estimation methods on alluvial fans using an integrated hydraulic, geological and geomorphological approach
Authors: Mollaei Zeinab , Davary Kamran , Hasheminia Seyed Majid , Faridhosseini Alireza , Pourmohamad Yavar
Published: April 2018

Abstract. Due to the uncertainty concerning the location of flow paths on active
alluvial fans, alluvial fan floods could be more dangerous than riverine
floods. The United States Federal Emergency Management Agency (FEMA) used a
simple stochastic model named FAN for this purpose, which has been practiced
for many years. In the last decade, this model has been criticized as a
consequence of development of more complex computer models. This study was
conducted on three alluvial fans located in northeast and southeast Iran
using a combination of the FAN model, the hydraulic portion of the FLO-2D model, and
geomorphological information. Initial stages included three steps:
(a) identifying the alluvial fans' landforms, (b) determining the active and
inactive areas of alluvial fans, and (c) delineating 100-year flood within
these selected areas. This information was used as an input in the mentioned
three approaches of the (i) FLO-2D model, (ii) geomorphological method, and
(iii) FAN model. Thereafter, the results of each model were obtained and
geographical information system (GIS) layers were created and overlaid.
Afterwards, using a scoring system, the results were evaluated and compared.
The goal of this research was to introduce a simple but effective solution
to estimate the flood hazards. It was concluded that the integrated method
proposed in this study is superior at projecting alluvial fan flood
hazards with minimum required input data, simplicity, and affordability, which
are considered the primary goals of such comprehensive studies. These
advantages are more highlighted in underdeveloped and developing
countries, which may well lack detailed data and financially cannot
support such costly projects. Furthermore, such a highly cost-effective
method could be greatly advantageous and pragmatic for developed countries.
A Novel Approach for Solving CNOP and its Application in Identifying Sensitive Regions of Tropical Cyclone Adaptive Observations
Authors: Zhang Linlin , Mu Bin , Yuan Shijin , Zhou Feifan
Published: April 2018

Abstract. In this paper, a novel approach is proposed for solving conditional nonlinear optimal perturbation (CNOP), named it adaptive cooperation co-evolution of parallel particle swarm optimization and wolf search algorithm (ACPW) based on principal component analysis. Taking Fitow (2013) and Matmo (2014) as two tropical cyclone (TC) cases, CNOP solved by ACPW is used to investigate the sensitive regions identification of TC adaptive observations with the fifth-generation mesoscale model (MM5). Meanwhile, the 60 km and 120 km resolutions are adopted. The adjoint-based method (short for the ADJ-method) is also applied to solve CNOP, and the result is used as a benchmark. To validate the validity of ACPW, the CNOPs obtained from the different methods are compared in terms of the patterns, energies, similarities and simulated TC tracks with perturbations. (1) The ACPW can capture similar CNOP patterns with the ADJ-method, and the patterns of TC Fitow are more similar than TC Matmo. (2) When using the 120 km resolution, similarities between CNOPs of the ADJ-method and ACPW are higher than those using the 60 km. (3) Compared to the ADJ-method, although the CNOPs of ACPW produce lower energies, they can obtain better benefits gained from the reduction of CNOPs, not only in the entire domain but also in the sensitive regions identified. (4) The sensitive regions identified by CNOPs-ACPW has the same influence on the improvements of the TC tracks forecast skills with those identified by CNOPs-ADJ-method. (5) The ACPW has a higher efficiency than the ADJ-method. All conclusions prove that ACPW is a meaningful and effective method for solving CNOP and can be used to identify sensitive regions of TC adaptive observations.
Estimation of sediment deposits in the Ghézala reservoir in northern Tunisia
Authors: Mathlouthi Majid , Lebdi Fethi
Published: April 2018

Abstract. The control of sedimentation in a reservoir provides a global evaluation of the process of erosion and transportation of sediment. Knowledge of sedimentation is useful for reservoir management. Bathymetric surveys can be used to assess the silting volume of dams. The results of two surveys of the Ghézala dam reservoir in northern Tunisia are available. The measurements provide initial information about the quantity and variability of silting and the mechanism of sediment deposition. According to the results of measurements, the average annual specific sediment yield of the Ghézala dam watershed is estimated at 1851 tkm-2yr-1. The annual average sediment volume trapped varies from 23 000 m3 in 1993 to 66 692 m3 in 2011. The sedimentation rates increases from 0.20 to 0.57 % overtime. The results indicate interdependence between the specific erosion rates and the occurrence of soils on steep slopes. The pressure exerted on the soil by plowing as well as overgrazing to meet the needs of the population of this area has exposed the soil to continued deterioration manifested by increased erosion endangering the only source of revenue for the area.