bluuebunny/crossref_metadata_2025_split huggingface dataset:
Precessional Drivers of Late Miocene Mediterranean Sedimentary Sequences: African Summer Monsoon and Atlantic Winter Storm Tracks
Authors: Marzocchi Alice , Flecker Rachel , Lunt Daniel J. , Krijgsman Wout , Hilgen Frits J. 
Published: November 2019

AbstractCyclic sedimentary patterns in the marine record of the Mediterranean Sea have been consistently correlated with orbitally‐driven shifts in climate. Freshwater input driven by the African summer monsoon is thought to be the main control of such hydrological changes, where the runoff signal is transferred from the eastern to the western Mediterranean. The geological record from the Atlantic margin also contains precession‐driven dilution cycles that have been correlated with the sedimentary sequences in the western and eastern Mediterranean despite the lack of a direct connection with the basin. In these regions, Atlantic winter storms have also been invoked to explain the wet phases. In the absence of seasonally‐resolved proxy data, climate simulations at high temporal resolution can be used to investigate the drivers of Mediterranean hydrologic changes both on precessional and seasonal timescales. Here, we use the results of 22 ocean‐atmosphere‐vegetation simulations through an entire late Miocene precession cycle. These show that the African summer monsoon drives the hydrologic budget in the Eastern Mediterranean during precession minima, while the western marginal basins are generally dominated by local net evaporative loss. During precession minima, the western Mediterranean and the Atlantic margin are also influenced by enhanced winter precipitation from the Atlantic storm tracks. We can, therefore, identify two different moisture sources affecting the circum‐Mediterranean area, characterized by the same phasing with respect to precession, but with opposite seasonality. This supports the interregional correlation of geological sections in these areas, as we show for the Messinian and speculate for other time periods.
The Influence of Sudden Commencements on the Rate of Change of the Surface Horizontal Magnetic Field in the United Kingdom
Authors: Smith A. W. , Freeman M. P. , Rae I. J. , Forsyth C. 
Published: November 2019

AbstractSudden commencements (SCs) are rapid increases in the northward component of the surface geomagnetic field, related to sharp increases in the dynamic pressure of the solar wind. Large rates of change of the geomagnetic field can induce damaging currents in ground power networks. In this work, the effect of SCs on the (1 min) rate of change of the surface magnetic field (R) at three U.K. stations is investigated. The distributions of R during SCs are shifted to higher values than the data set as a whole. Rates of change greater than 10 nT/min are 30–100 times more likely during SCs, though less than 8% of the most extreme R (≥99.99th percentile) are observed during SCs. SCs may also precede geomagnetic storms, another potential source of large R. We find that the probability of observing large a R is greatly enhanced for 3 days following an SC. In the 24 hr following an SC it is 10 times more likely than at any given time to observe rates of change between 10 and several hundred nT/min. Additionally, between 90% and 94% of data (depending on station) above the 99.97th percentile is recorded within 3 days of an SC. All values of R ≥ 200 nT/min in the United Kingdom have been observed within 3 days of an SC. These results suggest that accurately predicting SCs is critically important to identify intervals during which power networks at similar geomagnetic latitudes to the United Kingdom are at risk from large geomagnetically induced currents.
Hydrological Drought Simulations: How Climate and Model Structure Control Parameter Sensitivity
Authors: Melsen L. A. , Guse B. 
Published: November 2019

AbstractHydrological drought, defined as below‐average streamflow conditions, can be triggered by different mechanisms, which are to a large extent dictated by the climate. Moreover, the simulation of hydrological droughts highly depends on the model structure and how drought‐triggering mechanisms are parameterized. In this large‐sample hydrological study, we investigate how climate and model structure control hydrological drought simulations. We conducted sensitivity analysis on parameters of three frequently used hydrological models (HBV, SAC, and VIC) for the simulation of drought duration and drought deficit over 605 basins covering more than 10 different Köppen‐Geiger climates. The sensitivity analysis revealed that, as anticipated, different parameters are sensitive in different climates. However, not all expected drought mechanisms were reflected in the parameter sensitivity: Especially, the sensitivity of ET parameters does not align with the theory, and the role of snow parameters in snow‐related droughts shows a distinction between degree‐day‐based models and energy‐balance models. Besides parameter sensitivity being different over climates, we also found that parameter sensitivity differed over the different models. Where HBV and SAC did display fairly similar behavior, in VIC other model mechanisms were triggered. This implies that conclusions on driving mechanisms in hydrological drought cannot be based on hydrological models only, as different models would lead to different conclusions. Hydrological models can have heuristic value in drought research, to formulate new theories and identify research directions, but formulated theories on driving processes should always be backed up by observations.
Depth‐Resolved Groundwater Chemistry by Longitudinal Sampling of Ambient and Pumped Flows Within Long‐Screened and Open Borehole Wells
Authors: Poulsen David L. , Cook Peter G. , Simmons Craig T. , Solomon D. Kip , Dogramaci Shawan 
Published: November 2019

AbstractDepth‐resolved chemistry samples are critical to a wide range of groundwater investigations. If a well intersects zones of variable concentrations, a pumped sample is a composite of the inflows, which mix in the well. Where discrete concentrations are required, excessive mixing makes samples less useful and potentially misleading. However, installations for depth‐discrete sampling are expensive, particularly for regional studies, so sometimes there is incentive to use existing infrastructure designed for other purposes (e.g., supply wells). This paper shows how the resolution of groundwater chemistry derived from long‐screened and open borehole wells can be improved by measuring and sampling the in‐well vertical flow regimes in ambient (unpumped) and/or pumped conditions. The ambient flow regime, driven by a natural vertical head gradient, is shown to be particularly useful to sample groundwater native to defined inflow zones (head in the zone > head in the well) and avoid zones impacted by the invasion of intraborehole flow (head in the zone < head in the well). Depth‐specific samples are interpreted either as native groundwater from a discrete source, subject only to analytical error, or a mixture from multiple sources that can be deconvolved, incorporating error in both flow and concentration measurements. Depth‐resolved age tracers (chlorofluorocarbons, 14C, and He) in groundwater from three supply wells are verified with samples from a multidepth nest of piezometers. Results show old groundwater at all depths and the simultaneous occurrence of young water at shallower depths in undisturbed dual‐porosity fractured aquifers in the Pilbara region of Western Australia.
Non‐Newtonian Backflow in an Elastic Fracture
Authors: Chiapponi Luca , Ciriello Valentina , Longo Sandro , Di Federico Vittorio 
Published: November 2019

AbstractBackflow phenomenon, as a consequence of hydraulic fracturing, is of considerable technical and environmental interest. Here, backflow of a non‐Newtonian fluid from a disk‐shaped elastic fracture is studied theoretically and experimentally. The fracture is of constant aperture h and the outlet section at constant pressure pe. We consider a shear‐thinning power‐law fluid with flow behavior index n. Fracture walls are taken to react with a force proportional to hλ, with λ a positive elasticity exponent; for λ=1 linear elasticity holds. Constant overload f0, acting on the fracture, is also embedded in the model. A transient closed‐form solution is derived for the (i) fracture aperture, (ii) pressure field, and (iii) outflow rate. The particular case of a Newtonian fluid (n=1) is explicitly provided. For pe=0 and f0=0, the residual aperture and outflow rate scale asymptotically with time t as t−n/(n+λ+1) and t−(2n+λ+1)/(n+λ+1), respectively, thus generalizing literature results for n=1 and/or λ=1. For nonzero exit pressure and/or overload, the fracture aperture tends asymptotically to a constant value depending on λ, n, pe, f0, and other geometrical and physical parameters. The results are provided in dimensionless and dimensional form, including the time to achieve a given percentage of fluid recovery. In addition, an example application (with values of parameters derived from field scale applications) is included to further characterize the influence of fluid rheology. Experimental tests are conducted with Newtonian and shear‐thinning fluids and different combinations of parameters to validate the model. Experimental results match well the theoretical predictions, mostly with a slight overestimation.
A diurnal carbon engine explains13C-enriched carbonates without increasing the global production of oxygen
Authors: Geyman Emily C. , Maloof Adam C. 
Published: November 2019

SignificanceWe present stable carbon isotope (δ13C) data from modern carbonate sediment that require a decoupling of the carbon cycles in the global ocean versus shallow carbonate shelves. This realization is important because, for the first 97% of Earth history, many inferences about global paleoclimate and seawater chemistry rely on interpretations of shallow carbonates. We use modern observations and a simple model to show how ordinary diurnal carbon cycling in shallow waters is sufficient to produce anomalously positiveδ13C on shelves today, and in the geological record. Our results alleviate the need to interpret positiveδ13C excursions in the geological record as global reorganizations of the carbon cycle and instead linkδ13C to local and/or global paleoenvironmental and paleoecological controls.
Traveling wave solutions for the spatial diffusion of bird flu model
Authors: Rince Putri Arrival , Husna Radhiatul 
Published: November 2019

Abstract
We describe mathematical model to study bird flu transmission in bird system and human system. The behaviour of this model was analyzed through stability of constant solutions. Our result shows that these stabilities depend on values of some parameters. Furthermore, the model of bird system is reformulated by adding diffusive term. Traveling wave solutions of the diffusive model were investigated. The positive solutions are numerically illustrated with homogeneous Neumann boundary conditions. The result shows that transmission progress can be expressed in form of a traveling wave solutions.
Direct and indirect grouping strategies for a multi-item probabilistic inventory model
Authors: Koswara Handi , Lesmono Dharma 
Published: November 2019

Abstract
In this paper we develop joint replenishment strategies, namely direct and indirect grouping to find the optimal solution for a multi-item probabilistic inventory problem. Basically, direct grouping is a strategy to group items according to a predetermined ratio of holding cost and minor ordering cost. On the other hand, in indirect grouping strategy, items are ordered every predetermined basic cycle time with a possibility that not all items are ordered. We assume that demands are normally distributed and all shortages are backordered. In developing our model, we also develop an algorithm for direct and indirect grouping. In the numerical experiments, we consider six items with their own parameters, ordered from one supplier, and compare the total inventory cost between direct and indirect grouping strategies. We found that in our examples that indirect grouping strategies gives lower total inventory cost than direct grouping strategy.
Path analysis of entrepreneurial motivations in tourism based on local resources and creative economy in nagari salayo of west sumatra
Authors: Devianto Dodi , Ridho Muhammad , Maryati Sri , Lenggogeni Sari 
Published: November 2019

Abstract
The purpose of this study is to analyze the entrepreneurial motivations in tourism based on local resources and creative economy in Nagari Salayo of West Sumatra in developing this area into a cultural and creative based tourist destination. The sixty beginner entrepreneurs are involved in this research in community services, where their entrepreneurial motivations are measured by an entrepreneurial motivation scale of the questionnaire and analyzed by using path analysis in determining the relationship between personality characteristic motivation cores. The statistical path model showed significantly affecting of working motive and social motive to capability of entrepreneurial as a direct effect, in contrast only working motive influenced of intention of entrepreneurs, and the capability of entrepreneurial as mediation variable for indirect effects of entrepreneurial motive to intention entrepreunerial. This analysis suggests the model that entrepreneurial motivations have effect to capacity and intention of beginner entrepreneurs to develop business on tourism based on local resources and the creative economy.
Poisson gamma model in empirical Bayes of small area estimation (SAE)
Authors: Yanuar Ferra , Eka Putri Nadya Cindy , Yozza Hazmira 
Published: November 2019

Abstract
This study aims to describe the empirical Bayes estimator for small area estimation which use Poisson Gamma as prior distribution. The method then apply to generated data and model it with and without indicator variable. Parameter model estimated uses direct method and indirect method (known as empirical Bayes approach; with and without indicator variable). The choice of better estimator is based on MSE with Jackknife method. The criteria of acceptable proposed model are based on Deviance, Scaled Deviance, Pearson ChiSquare and Scaled Pearson Chi-square. This study proves that empirical Bayes in SAE with indicator variable result better estimated values than two other methods. All criteria of acceptable model indicate that proposed model could be accepted. Based on plot between the estimated residual versus predicted values of response variable informed that proposed model is plausible enough.
Leaf feature extraction using glcm, moment invariant and shape morphology for indonesian medicinal plants recognition
Authors: Syahputra Hermawan , Indra Zulfahmi , Febrian Didi , Putri Adriani Dhea 
Published: November 2019

Abstract
This study aims to determine the extraction of GLCM texture features, shape morphology and moment invariant features on the leaf image of medicinal plants and determine the accuracy of plant recognition based on these three features by using Artificial Neural Network Classifiers. The procedure performed to classify medicinal plants based on their leaf image is image acquisition, image pre-processing, feature extraction, image classification and calculating the accuracy of test results. The introduction had tested for ten Indonesian medicinal plant samples, namely: Bangun-Bangun, Binahong, Jarak, Kemuning, Mangkokan, Mengkudu, Pegagan, Sambiloto, Sambung Nyawa, and Sirih. Based on the test results, obtained 97% accuracy with GLCM features, 69% with Shape Morphological features, 86% with GLCM and Shape Morphological features and 79% with moment invariant features.
Constructive heuristic for the mixed capacitated arc routing problem with multi capacity
Authors: Masran H , Ramli M F 
Published: November 2019

Abstract
This paper addresses a variant of the capacitated arc routing problems known as the mixed capacitated arc routing problem (MCARP) with multi capacity constraints. The MCARP represents closely real life situations since it takes into account directed and undirected links to serve customers in the associated network. A constructive heuristic based on insertion techniques is proposed to tackle the problem. Computational experiments were conducted using some randomly generated instances and the experiments show competitive results. Some avenues for future research are also highlighted.
Characteristics of bidikmisi’s scholarship awardee in FMIPA UNP using chi-squared automatic interaction detection
Authors: Amalita Nonong , Kurniawati Yenni , Fitria Dina 
Published: November 2019

Abstract
Bidikmisi’s Scholarships is a funding assistance from government to help students in the university who lack economically but good in academic. Number of awardee in FMIPA UNP increases yearly. So, we have to know classification of awardee to make sure that scholarship is received by the right one. We use CHAID-Chi-Squared Autimatic Interaaction Detection analysis. Result of the research, there are five groups awardee. Characteristics of awardee is father’s jobs (farmers, motor driver, jobless) and area of their house approximately 50 m2.
Variational approximations for intersite soliton in a cubic-quintic discrete nonlinear Schrödinger equation
Authors: Putri N Z. , Asfa R. , Fitri A A. , Bakri I. , Syafwan M. 
Published: November 2019

Abstract
In this paper, the approximation for stationary soliton solution with intersite-typed configuration in the cubic-quintic DNLS equation for anti-continuum limit is determined by a variational approximation (AV) method. The proposed ansatz is of the form an exponential function with three variational parameters. The obtained VA solutions are then examined its validation and compared with the corresponding numerical solutions. The results show that the VA solutions are valid and provide a very good agreement with the numeric.
The Comparison of Fourth Order Runge-Kutta and Homotopy Analysis Method for Solving Three Basic Epidemic Models
Authors: Yong B 
Published: November 2019

Abstract
All epidemic models include a system of non-linear differential equation. Mostly the analytical solution of epidemic model is difficult to obtain. There are many different methods to solve non-linear differential equation, one of them is homotopy analysis method. The homotopy analysis method is an analytic approximation method using series solution for highly non-linear equations. The advantage of this method is a guarantee the convergence of approximation power series solution by choosing suitable values of the auxiliary parameter. In this paper, we consider three epidemic models in a closed population without demographics; SI, SIR, and SEIR models. We find the solutions of the models by homotopy analysis method and then compare the numerical results with fourth order Runge-Kutta method. The homotopy analysis method gives a good result for the solution of the epidemic models with a few iterations and the solutions obtained from this method are good as compared to fourth order Runge-Kutta numerical method.
Optimization and analysis of some oxinate metal complex system as introduction test for HPLC analysis
Authors: Oktavia Budhi , Purnama Sari Mega , Comala Sary Ratih , Lisa Mona , Nasra Edi , Zainul Rahadian , Efendi Jon 
Published: November 2019

Abstract
Heavy metals are metals that have a mass of more than 5 g / cm3 in the lower right corner of the periodic system. Heavy metals rarely form atoms themselves in water, but are usually bound by other compounds to form molecules. Heavy metal is a chemical compound that has the potential to cause environmental pollution problems. Methods of heavy metal content analysis in the aquatic environment developed simultaneously are still being developed. The simultaneous analysis provides an advantage in terms of time and cost efficiency. In this study is being developed heavy metal analysis based on the formation of complexes with oxin compounds. It is known that the oxide can form a yellow complex with several metal ions. The use of oxine as a complex is selected based on the color and pH of the complexes formed. By performing optimization and analysis of the complex system formed it is expected to produce an excellent method for the analysis of several heavy metals simultaneously using High Performance Liquid Chromatography (HPLC).
Application of chitosan crosslink as selective adsorbent
Authors: Hasri  , Auliah Army , Pratiwi Diana E , Sulfikar  , Yusaerah Nur 
Published: November 2019

AbstractA selective chitosan adsorbent may remove Cd2+and Pb2+ions in aquatic environment to reduce pollution. This study has applied crosslink chitosan to reduce Cd2+and Pb2+ions in water. The study is related to the searching of optimum condition with respect to citric acid and sodium tripolyphosphate concentrations in a batch method. The study also includes the determination of optimum pH and interaction study of complex molecule with either Cd2+or Pb2+ions in relation to competitive chitosan adsorption. The optimum pH is found at pH 5. The optimum concentration of citric acid with chitosan is found to be 1% (b / v). It is concluded that chitosan adsorbent is selective for Pb2+over Cd2+ions.
Preparation and characterization of herbal shampoo from goat milk and natural extract
Authors: Sastrawidana D. K. , Pradnyana G.A. , Madiarsa M. 
Published: November 2019

Abstract
Shampoo is one of the cosmetic type product using surfactants as the main compound which when used under the specified conditions will remove surface grease, dirt, and skin debris from the hairs without adversely affecting the user. Currently shampoo is not only used to cleanse dirt on the hair and scalp but also to hair growth and prevent hair loss. To achieve this goal, the shampoo industries used a variety of additives chemicals that can potentially risk for user. In this study, we tried to make two types of herbal shampoo using natural leafs extract. The formula of shampoo 1, consist of goat milk, celery leaf extract, banana knot extract, and pegagan leaf extract while shampoo 2 using goat milk, noni extract, mangkokan leaf extract and spinach extract. Both of that shampoo preparations were analyzed the physical appearance and physicochemical. The results showed that the physical performance both herbal shampoo were light brown in color, transparent and good odor while the physicochemical characteristics of herbal shampoo formula 1 comprise pH, solid content, surface tension and foam ability were 5.25; 29.17%; 51.17 dyne/cm and 9.50 mL, while herbal shampoo formula 2 has a pH of 5.5; solid content of 29.67%; surface tension of 44.63 dyne/cm and foam ability of 15.0 mL. Formulated herbal shampoo shows physicochemical properties comparable to the commercial shampoo.
The tumor necrosis factor-α gene polymorphism (-308g/a) in type 2 diabetes mellitus patients with tuberculosis infection
Authors: Indah Sari Mutiara , Daulay Milahayati , Widyawati Tri , Rita Anggraini Dwi , Dwi Wahyuni Dian , Syarifah Siti 
Published: November 2019

Abstract
The tumor necrosis factor (TNF)-a gene polymorphism (-308G/A) has been shown influence several diseases. This study aims to analyze the distribution of the TNF-α gene polymorphism (-308G/A) in type 2 diabetes mellitus (T2DM) patients with tuberculosis infection. Forty of T2DM patients with tuberculosis infection were recruited at Balai Pengobatan Lung Disease, Medan. Data collection of characteristics subjects were done through interviews using questionnaires. The blood glucose were measured with a spectrophotometer at a wavelength of 500 nm. Nco1 restriction enzyme was used to digested of gene polymorphism (-308G/A). Genotype frequency of the TNF-α gene was analyzed by direct counting. In this study shown that the TNF-α gene polymorphism (-308G/A) had 38 (95%) of G/G genotype and 2 (5%) of G/A genotype. No A/A genotype shown in this population. This preliminary result indicated that G/G genotype was common genotype in the TNF-α gene polymorphism (-308G/A) in T2DM patients with tuberculosis infection.