Miracle-dz/UniFAR-FTUs huggingface dataset:
Quantifying the impact of Ramadan on global raw sugar prices

Purpose The purpose of this study is to quantify the impact of Ramadan on both the level and the growth of global raw sugar price. Design/methodology/approach The study uses a dummy and a fractional variable to capture Ramadan to overcome the asynchronicity of time between Ramadan fasting (which is based on the Islamic lunar calendar) and the movement in prices (which follows the Gregorian solar calendar). To capture the seasonality of sugar production, the data on sugar price span 34 years so that the Islamic calendar makes a complete cycle of the Gregorian calendar. The empirical model is estimated using both autoregressive integrated moving average model and unobserved components model. Findings The results show that monthly raw sugar prices in the global market increases by roughly 6.06 per cent (or $17.78 per metric ton) every year ahead of Ramadan. Practical implications The study illustrates the implications of the results for the consumption of imported sugar in Bangladesh. Originality/value The study uses a broader set of Ramadan indicators in its empirical models and checks the robustness of its baseline model using the unobserved components model. It also performs seasonal unit root tests on the global raw sugar prices.
Mesozooplankton of the lower San Francisco Estuary: spatio-temporal patterns, ENSO effects and the p

The San Francisco Estuary (SFE) is a large, highly dynamic and ecologically important estuary on the west coast of the USA. We collected zooplankton and hydrographic data over a 3-year period (1997–1999) at six stations spanning the lower SFE to investigate long-term changes through comparison with a 1980– 1981 survey of the area, El Nino-Southern Oscillation (ENSO) effects and the prevalence of non-indigenous species. Spatio-temporal patterns in the zooplankton were primarily regulated by seasonal and inter-annual fluctuations in marine and riverine forcings. Non-metric multidimensional scaling accounted for 82.7% of the variation in zooplankton composition. The strongest correlates of the three axes were salinity (r 1⁄4 0.692), distance to marine influence and temperature (r 1⁄4 0.492 and 0.309, respectively) and a lagged multivariate ENSO index (r 1⁄4 0.299). Five zooplankton communities were identified, which showed predictable spatiotemporal progressions through the lower estuary. Inter-annual differences between El Nino and La Nina periods were substantial and appeared to be related to variable strengths of riverine and oceanic forcing. Between 1980–1981 and 1997– 1999, a dramatic change occurred in the zooplankton of the lower SFE, such that dominance has shifted from native calanoid copepods to non-indigenous (Asian) cyclopoids. These changes in the zooplankton are expected to have significant but as yet unknown impacts on higher tropic levels and food web dynamics in the lower SFE.
THE SHAPE OF THE PHANEROZOIC MARINE PALAEODIVERSITY CURVE: HOW MUCH CAN BE PREDICTED FROM THE SEDIMENTARY ROCK RECORD OF WESTERN EUROPE?

Abstract: Palaeodiversity curves are constructed from counts of fossils collected at outcrop and thus potentially biased by variation in the rock record, specifically by the amount of sedimentary rock representative of different time intervals that has been preserved at outcrop. To investigate how much of a problem this poses we have compiled a high‐resolution record of marine rock outcrop area in Western Europe for the Phanerozoic and use this to generate a model that predicts the sampled diversity curve. We find that we can predict with high accuracy the variance of the marine genus diversity curve (itself dominated by European taxa) from rock outcrop data and a three‐step model of diversity that tracks supercontinent fragmentation, coalescence and fragmentation. The size and position of two of the five major mass extinction spikes are largely predicted by rock outcrop data. We conclude that the long‐term trends in taxonomic diversity and the end‐Cretaceous extinction are not the result of rock area bias, but cannot rule out that rock outcrop area bias explains many of the short‐term rises and falls in sampled diversity that palaeontologists have previously sought to explain biologically.
A Priori Feedback Estimates for Multiscale Reaction-Diffusion Systems

ABSTRACT We study the approximation of a multiscale reaction–diffusion system posed on both macroscopic and microscopic space scales. The coupling between the scales is done through micro–macro flux conditions. Our target system has a typical structure for reaction–diffusion flow problems in media with distributed microstructures (also called, double porosity materials). Besides ensuring basic estimates for the convergence of two-scale semi-discrete Galerkin approximations, we provide a set of a priori feedback estimates and a local feedback error estimator that help in designing a distributed-high-errors strategy to allow for a computationally eﬃcient zooming in and out from microscopic structures. The error control on the feedback estimates relies on two-scale-energy, regularity, and interpolation estimates as well as on a fine bookeeping of the sources responsible with the propagation of the (multiscale) approximation errors. The working technique based on a priori feedback estimates is in principle applicable to a large class of systems of PDEs with dual structure admitting strong solutions.
Penalized Least Squares for Optimal Sparse Portfolio Selection

Markowitz portfolios often result in an unsatisfying out-of-sample performance, due to the presence of estimation errors in inputs parameters, and in extreme and unstable asset weights, especially when the number of securities is large. Recently, it has been shown that imposing a penalty on the 1-norm of the asset weights vector not only regularizes the problem, thereby improving the out-of-sample performance, but also allows to automatically select a subset of assets to invest in. Here, we propose a new, simple type of penalty that explicitly considers financial information and consider several alternative non-convex penalties, that allow to improve on the 1-norm penalization approach. Empirical results on U.S.-stock market data support the validity of the proposed penalized least squares methods in selecting portfolios with superior out-of-sample performance with respect to several state-of-art benchmarks.
THE EFFECT OF HOUSEHOLD CHEMICALS ON SEPTIC TANK PERFORMANCE

Maintenance of sewage treatment systems is useful to identify dead septic tanks and to determine the cause, which is often heavy use of detergent with bleach or heavy disinfectant use in general. When detergent without bleach is substituted, treatment typically recovers completely. A field experiment to quantify the effects of household chemicals was carried out using lowstrength wastewater dosed at a diurnal rate to four 100 L pilot-scale septic tanks and calibrated to four-day residence time. Mixtures of detergent with bleach and bleach pucks were used, with dose concentrations calibrated to tank size and to laundry or toilet volumes. After a one-week start-up period, chemicals were dosed for 2 weeks, stopped for 2 weeks (by accident), and started again for 4 weeks, followed by 2 weeks of no chemicals. The experimental run was divided into two sets, Set A with no chemicals dosed and Set B with chemicals dosed. Average %BOD removals were calculated at each sampling day and a “paired t-test” was employed to compare the significance of the differences between Tests and the Control for each set. The paired t-test on BOD removal rates showed that for Set A (no chemicals dosed) there were significant differences between the pilot-scale septic tanks receiving detergent (ST-1 – 75% poorer removal efficiency) and BOTH chemicals (ST-4 – 71% poorer removal efficiency) at the 95% confidence level, primarily due to the divergent effluent BOD concentrations found at the beginning of the experimental run. Towards the end of the experimental run, after chemical dosing is ceased, all pilot-scale septic tanks seemed to perform equally indicating that septic tanks recover quite readily. ST-3 receiving flush puck solution (29% poorer removal efficiency) showed no significant difference compared to the control. The paired t-test for Set B showed that the differences between ST-1 (88% poorer removal efficiency) and ST-4 (200% poorer removal efficiency) compared to the Control were significant at the 95% confidence level. The addition of flush puck solution (ST-3) seemed to actually improve %BOD removal (31% higher removal efficiency), but the difference was not statistically significant compared to the Control. Fecal Coliforms were typically lower than the Control, but not diagnostic, suggesting no widespread ‘kills’ at these levels of chemical addition. Dead septic tanks are caused by greater use of disinfectants than used in this experiment.
Forty-Fifth Annual Allerton Conference on Communication, Control, and Computing

This paper initiates the study of scaling laws for vehicular ad hoc networks (VANET)s. It provides a general framework to study VANETs. The fundamental capacity limits of these networks are investigated and we show how the road geometry affects this capacity. The VANET capacity is calculated for different road structures. The need for new capacity metrics is discussed. These results are obtained by combining geometrical analysis, network flow arguments, and probabilistic study of VANETs.
Recent advances in self-consistent RF sheath modeling and relatedphysical properties: Application to Tore Supra IC antennae

Non-linear wave-plasma interactions in the plasma edge often set the operational limits for radio-frequency (RF) heating systems. Some peripheral Ion Cyclotron (IC) wave energy loss is attributed to a net direct current (DC) biasing of the edge plasma by RF-sheath rectification. In order to understand the underlying mechanisms driving these interactions, SSWICH (Selfconsistent Sheath and Wave for IC Heating) models self-consistently the interplay between RF wave propagation and edge plasma biasing, using a two-field fluid approach. RF and DC parts are coupled through non-linear RF and DC sheath boundary conditions (SBC). The iterative resolution of the coupled RF+DC model experiences convergence issues in the wide sheaths regime, i.e. large DC biasing relevant in the vicinity of high-power RF launchers. In order to overcome this difficulty and provide a first guess of the solution, the self-consistent RF+DC system was solved explicitly for the first time in this asymptotic wide sheaths limit, while keeping the possibility to excite the system by any realistic RF field map. Several original physical properties were observed. The radial penetration of the RF sheaths along lateral walls at both ends of the open magnetic field lines can be far deeper than the skin depth characteristic of the slow wave (SW) evanescence. This is interpreted invoking the Sheath-Plasma Wave, only appearing in the presence of sheaths and carrying them along material boundaries up to their leading edge. The RF voltages driving sheaths were shown to scale as the square root of the input RF power, consistent with some experimental observations and valuable for antenna design. This is illustrated in the case of Tore Supra antennae by the comparison of two Faraday screens with different electrical design that were experimented upon last year simultaneously. Since only the edge plasma is actually meshed, another issue is the emulation of radiating conditions in order to avoid reflections at the inner boundary of the domain. A versatile perfectly matched layer (PML) adapted to any medium was thus developed and extensively tested as an artificial dielectric material. As tokamak magnetized plasmas present two wave eigenmodes with opposite group velocities, simultaneous adaptation is impossible. The PML is accordingly adapted only for the fast wave if the plasma domain is far thicker than the SW skin depth. The PML should also be placed beyond the coupling zone of the fast wave
An Intimacy-based Trust Reasoning Method for Intelligent Ecommerce Systems

전자상거래에서 신뢰도는 전자상거래 서비스 제공업체의 비가시성이나 그들의 평판으로 인한 소비자의 우려를 완화시켜주기 때문에 사용자의 신뢰수준을 추정하는 것은 전자상거래의 지속적 사용에 있어 중요한 기술이다. 기존의 신뢰도 측정법은 주로 전자상거래 시스템에서 사용된 정책과 평판기반의 추론에 근거한 사용자들의 초기 경험에 중심을 두었다. 그러나, 보다 성숙된 단계의 전자상거래 시스템 지속사용 가능성 추정을 위한 신뢰도 측정에 대해서는 별다른 대안이 없었다. 따라서 본 연구에서는 성숙단계에서의 전자상거래 시스템에 알맞은 신뢰도 추론방법을 제안한다. 특히, 친밀도는 평판뿐 아니라 신뢰도와도 깊이 관계하고 있기때문에 사용자의 입력을 강제하지 않는 친밀도 측정 방법을 새롭게 개발하였다. 성과 측정을 위한 실험에서는 제안된 방법이 유효하고, 평판기반의 신뢰도 추론과 함께 사용할 수 있는 것으로 나타났다.
Determining Statistical Pattern on the Drug-Related Killing in Philippines Using ARIMA and Poisson Techniques

A univariate time series technique was conducted to determine statistical pattern on killings of drug suspects in Philippines from May 19 to July 7, 2016. The technique reveal a moving-average of order 2, MA(2) with a positive coefficient suggestive that value of outcome variable tend to increase, on the average, than the recent value of . This means that drug-related killings will tend to be higher than the most current rate; and killings is seen to increase as weekend comes. Poisson regression indicated an average of 13 deaths on a Sunday; only 2 on average on a Monday; odds of survival increases as well as weekend comes. Finally, the forecast model and the simulation are limited by the data used. Structure of the univariate series may change as additional data are added; this is also true for the forecasted average occurrence.
ROWORDNETLIB - THE FIRST API FOR THE ROMANIAN WORDNET

The article presents RoWordNetLib, a Java Application Programming Interface (API) for the Romanian WordNet (RoWN). RoWN is a mature semantic network mirroring Princeton WordNet, and it is in continuous development by RACAI since its first version in 2004. A wordnet is a very useful resource in several domains such as Information Retrieval, Information Extraction, Word Sense Disambiguation, etc. The development of this API is meant to ease the use of the Romanian WordNet in both academic and industry environments. We implemented several distinct functionality classes: RoWN file input/output, wordnet programmatic access methods, set operations on multiple wordnet objects, word sense disambiguation basic algorithms that enable the use of distance-based and semantic similarity functions. The API is open-source, freely available and extendible.
Scene surface light field representation for realistic lighting

Abstract. Existing light field-based lighting follows the representation on plane, such as the commonly used light slab. A novel light field representation on scene surface is proposed. The illumination is captured by a panorama camera on translation stage with a nonuniform sampling and calibration strategy. Sampled light rays are reprojected on the reconstructed scene to generate the scene surface light field representations for both direct light source and indirect light. This representation is more consistent with the actual emission and reflection of light transport than the existing ones. An accurate light source estimation and a practical indirect light resampling approach are presented based on the representation. The rendering results illustrate the realistic lighting effect, especially in spatially varying illumination.
Mixing efficiency in run-down gravity currents

This paper presents measurements of mixing efficiency of the two counter-flowing gravity currents created by symmetric lock exchange in a channel. The novel feature of this work is that the buoyancy Reynolds number of the currents is higher than in previous experiments, so that the mixing is not significantly affected by viscosity. We find that the mixing efficiency asymptotes to 0.08 at high Reynolds numbers. We present a model of the mixing based on the evolution of idealized mean profiles of velocity and density at the interface between the two currents, the results of which are in good agreement with the measurements of mixing efficiency.
The Xylariaceae of the Hawaiian Islands

Keys, species notes, references, hosts, and collection locations of the following xylariaceous genera are included: Annulohypoxylon, Ascovirgaria, Biscogniauxia, Daldinia, Hypoxylon, Jumillera, Kretzschmaria, Lopadostoma, Nemania, Rosellinia, Stilbohypoxylon, Xylaria, and Xylotumulus. Camarops and Pachytrype --non-xylariaceous genera--are included. Anthostomella, well-covered elsewhere, is not included here. A Host-Fungus Index is included. A new name, Xylaria alboareolata , is proposed. All of the Hawaiian Islands are included, but Lanai was not visited.
The Relationship between a Firm’s Value and Ownership Structure in Kuwait: Simultaneous Analyses Approach

The study examined the impact of ownership structure on the value of listed firms in Kuwait using endogeneity theory as an analytical framework. Ownership structure was measured in terms of ownership concentration (percentage of shares owned by all top shareholders), while measures of value were Tobin’s Q and Return on Assets. In the study, we used panel data for 121 firms listed on the Kuwait Stock Exchange (KSE) from 2010 to 2012, and we specified a model that used simultaneous equations with empirically-validated, strong, instrumental variables to control for endogeneity and causality issues. The results of the study indicated that ownership concentration had a negative, but insignificant, relationship with a firm’s value based on OLS regression. However, based on 2SLS regression, ownership concentration was found to have a significant negative relationship with a firm’s value However, the causality relationship between firm value and ownership concentration, if any, was from ownership concentration to firm value based on 2SLS regression. Therefore, there are two main contributions of this paper that make it a good addition to the extant literature, i.e., 1) it examined the relationship between firm value and ownership structure using the most recent data and 2) no work was done before the issues of endogeneity and causality for firms listed on the KSE were examined.
Experimental evaluation of synergy-based in-hand manipulation

Abstract In this paper, the problem of in-hand dexterous manipulation has been addressed on the base of postural synergies analysis. The computation of the synergies subspace able to represent grasp and manipulation tasks as trajectories connecting suitable configuration sets is based on the observation of the human hand behavior. Five subjects are required to reproduce the most natural grasping configuration belonging to the considered grasping taxonomy and the boundary configurations for those grasps that admit internal manipulation. The measurements on the human hand and the reconstruction of the human grasp configurations are obtained using a vision-based mapping method that assume the kinematics of the robotic hand, used for the experiments, as a simplified model of the human hand. The analysis to determine the most suitable set of synergies able to reproduce the selected grasps and the relative allowed internal manipulation has been carried out. The grasping and in-hand manipulation tasks have been reproduced by means of linear interpolation of the boundary configurations in the selected synergies subspace and the results have been experimentally tested on the UB Hand IV.
WHEN OPINION LEADERS TWEET: FRAMING ANALYSIS OF KUWAITI PARLIAMENT MEMBERS' TWEETS

This research investigated Kuwaiti parliament members’ leadership behavior on Twitter by applying Bolman and Deal’s (1984) leadership theory of framing. The study classified parliament members according to their political party affiliation-Islamists, independents, liberals, and populists party- and investigated the prevalence of four leadership frames through a content analysis of eight parliament members’ messages on Twitter over a period of six months from June 15, 2011 to November 15, 2011. Results showed that, overall, the structural frame was the most commonly used frame among parliament members, followed by the political, symbolic, and human resource frame respectively. The use of frames depended on both the political group and the topic of issues. The Islamist group, liberal and populist party more often used the structural frame in their Twitter messages whereas the independent group more often used the political frame.
Identifying the relationships among Guanxi, political climate and power bases—Evidence from Taiwan

Although Guanxi, political climate, and power are common business practices in the workplace, the popularity in research has yet to be intensified. This study aims to explore the effects of Guanxi, political climate, and power bases and the moderating effects of political climate. Questionnaires were issued to workers across service and manufacturing industries and 1099 valid responses were collected. The results from hierarchical regression analyses indicated significant relationships between Guanxi and power bases in various patterns. Significant relationships also emerged between political climate and power bases. Partial mediating effects of political climate were found between the relationships of Guanxi and power bases. Recommendations, suggestions, and conclusions were also presented on the basis of the empirical findings.
Productivity Shocks, Unemployment Persistence, and the Adjustment of Real Wages

This paper applies a set of unit root and cointegration tests with non-linear error-correction mechanisms to a subset of the OECD countries to investigate the empirical conclusions of some of the labor market models in the literature. I generally find that the unemployment rate, productivity, and real wages have a unit root even if one controls for threshold effects. This finding justifies the use of a cointegration approach to assess the existence of a long-run equilibrium among the variables of interest. For roughly half of the OECD countries in the sample, the unemployment rate, real wages, and productivity trend together over time. For four countries (i.e, Germany, Japan, Sweden, and the US) the adjustment to the long run relationship appears mostly asymmetric. Also, an impulse response function analysis suggests that real wages and productivity adjust faster to the long-run equilibrium, while shocks to unemployment take longer to extinguish. Also, according to the sign of the shocks, the unemployment rates respond differently. These findings suggest that a proper analysis of the behavior of productivity, real wages, and unemployment should consider non-linear adjustment mechanisms to long-run equilibrium since a liner approach would be biased.