Miracle-dz/UniFAR-FTUs huggingface dataset:
Attributable Risk Function with Clustered Survival Data

The Attributable Fraction or risk function (ARF) is used to measure the impact of an exposure on occurrence of disease within a population. For any prospective cohort study, risk is likely to be estimated using time to event or survival data. Attributable risk function with right censored survival data has been discussed by Samuelsen and Eide. We propose a natural extension of the ARF to clustered survival data, which are common in medical research. We derive an estimator of the ARF. Simulation studies are conducted to evaluate the performance of our method and investigate the consequences of ignoring the cluster effect in analysis.
Effect of Online Searches on Stock Returns

Various theoretical models assume that information seeking behavior of investors has an impact on prices. However, it is very difficult to empirically test this, since the actual information acquisition process of the investors is unobservable. Using a unique data set from Google Trends, I construct a search volume index (SVI) and use it to proxy for the information seeking behavior of retail investors. Using a portfolio based approach I document the asymmetric response of future returns to the changes in the google search volume. I find that the portfolio with the highest increase in the SVI has positive and significant alphas while portfolios with decrease in SVI show no significant results. My results are robust to alternative specifications of risk models, time frames and measures of search index. Overall, my results are in line with the hypothesis that retail investors’ trades can effect stock prices.
The Morávka meteorite fall: 1. Description of the events and determination of the fireball trajectory and orbit from video records

Abstract— The Morávka (Czech Republic) meteorite fall occurred on May 6, 2000, 11:52 UT, during the daytime. Six H5–6 ordinary chondrites with a total mass of 1.4 kg were recovered. The corresponding fireball was witnessed by thousands of people and also videotaped by 3 casual witnesses. Sonic booms were recorded by 16 seismic stations in the Czech Republic and Poland and by one infrasonic station in Germany. A total of 2.5% of the fireball eyewitnesses reported electrophonic sounds. Satellites in Earth orbit detected part of the fireball light curve.
The Application of Mom and Eecs On Em Scattering From Slot Antennas - Abstract *

In this paper, a hybridization method of moment (MOM) and equivalent edge currents (EECs) is presented to study the electromagnetic (EM) scattering from the slot antennas fed by the waveguides with arbitrary termination. The EECs is applied to calculate the EM scattering of a conducting plane, including the diffraction of edge, while the MOM is used to obtain the fields in the slots and deal with the coupling between them In conjunction with them, the EM scattering of the slot antennas can be evaluated quickly. Several results are presented, demonstrating the applicability of this technique.
Fast Standing Modes in Transversley Nonuniform Solar Coronal Slabs: The Effects of a Finite Plasma Beta

We examine the dispersive properties of linear fast standing modes in transversely nonuniform solar coronal slabs with finite gas pressure, or, equivalently, finite plasma beta. We derive a generic dispersion relation governing fast waves in coronal slabs, for which the continuous transverse distributions of the physical parameters comprise a uniform core, a uniform external medium, and a transition layer (TL) in between. The profiles in the TL are allowed to be essentially arbitrary. Restricting ourselves to the first several branches of fast modes, which are mostly interesting from an observational standpoint, we find that a finite plasma beta plays an at most marginal role in influencing the periods (P), damping times (τ), and critical longitudinal wavenumbers ( ), when both P and τ are measured in units of the transverse fast time. However, these parameters are in general significantly affected by how the TL profiles are described. We conclude that, for typical coronal structures, the dispersive properties of the first several branches of fast standing modes can be evaluated with the much simpler theory for cold slabs, provided that the transverse profiles are properly addressed and the transverse Alfvén time in cold MHD is replaced with the transverse fast time.
Potential of aeroponics system in the production of quality potato (Solanum tuberosum l.) seed in developing countries

The production of potato seed under conventional system has not been effective in avoiding or reducing the build up of pathogens and has consequently led to reduced quality potato seed and low crop yields. Plants once cleaned through meristem culture and induction of tuberization under aeroponics system, produce high quality potato seed tubers rapidly that are free from contamination of pathogens. Further multiplication of potato seed tubers under aeroponics also compliments tissue culture (micropropagation), as it clones minitubers in a short time and reduces numerous labour steps associated with direct use of plantlets from tissue culture into the field in the post flask stage. Minitubers from air-rooted plants are planted directly in the field without a need for acclimatization to such environments. This system, as is the case with micropropagation, has potential to increase income and reduce cost of production of quality seed, thereby, making it more accessible to growers in developing countries where potato production is heavily constrained by the use of poor quality seed tubers. This review gives an insight on the potential of aeroponics in compliment to plant tissue culture in revolutionalizing the potato seed production in the agricultural systems of developing countries. Key words: Aeroponics, tissue culture, potato seed.
Electrophysiological Evidence of Working Memory Updating Deficits in Children with Learning Disabilities

Recent behavioral studies suggest that children with learning disabilities (LD) have difficulty in working memory (WM) updating. However, as behavioral performance represents the summed activity of multiple stages of processing, the temporal locus of the WM updating deficit remains unclear. Here, we used an event-related potential (ERP) paradigm to compare the temporal mechanisms of WM updating in 21 children with LD (aged between 10 and 12 years) and 21 agematched controls while they performed the running memory task. Behavioral results showed that children with LD attained significantly lower accuracy when the task required updating. ERPs revealed that the occipital early P1 component and parietal late positive complex (LPC) amplitudes were lower in children with LD compared to controls when the task required children to remember a new stimulus. The LPC (1000-1500) amplitude correlated with the performance of academic and updating behavior. These results provide a novel electrophysiological evidence that children with LD have a specific impairment in early visual attention processing and
Out-of-Class Work in Teaching-Learning

Out-of-Class Work (OCW) is a crucial part of students’ learning process. The continuous assessment of students’ OCW opportunities to fix students’ mistakes and misunderstandings, while improving courses’ contents. Among many others, important aspects concerning OCW that are mostly ignored today in the evaluation process relate to: 1) how students hand over assignments and 2) the time they devote to each assignment. The Tools and Strategies for Competences Assessment (TASCA) is an Innovation and Quality Education Team of the Universitat Politècnica de València (UPV). Its goal is to gather and analyze OCW information in order to obtain evidences of the degree of achievement of certain learning outcomes, improve students’ on learning experience and enrich the course evaluation process. Preliminary results show that the lack of adequate OCW supervision leads to situations where teachers underestimate (or overestimate) the complexity of assignments. This leads to a waste of time or overloads the student. Coordination among courses is of prime importance to adequate students’ work to avoid workload peaks. Mor of relationship between the time devoted to tasks and the attained results lead to especial cases where despite the time invested in tasks resulting grades are low in general. This may reflect the fact that such tasks are poorly specified or are not adequately connected to courses’ contents. Finally, assessing the usefulness of tasks as perceived by students seems also mandatory attending to the impact that such perception has on students’ motivation.
Diagnostic CT: Are Patients Adequately Informed?

AIM: CT scanning is a widely utilised effective diagnostic tool. We aimed to establish whether patients are adequately informed prior to undergoing CT investigations. Methods: All adult patients with mental capacity attending the department for a CT study over a week period were invited to fill out a brief questionnaire prior to their scan. Results: 57 patients returned completed questionnaires. Overall 23% of patients were unsure or incorrect about the type of scan scheduled. Of patients attending with a new condition, 46% of them did not know their provisional diagnosis. Only 32 % of patients had insight into how a CT scan worked. This was taken to mean that the patient had included some reference to either x-rays, radiation or cross sectional imaging. Only 23% of patients were aware of potential complications of CT scans. Conclusion: Although written consent prior to CT scan is probably a step too far in providing patients with relevant risks/benefits of their investigation, we propose all patients undergoing CT have prior access to a written information sheet should they wish to be further informed regarding their procedure.
Value Relevance of Firm Specific Corporate Governance and Macroeconomic Variables: Evidence from Karachi Stock Exchange

This study examines the value relevance of firm specific corporate governance and macroeconomic variables of public listed non-financial companies in Karachi stock exchange (KSE) and also answers how a firm can increase its value relevance by incorporating most value relevant drivers in their financial management systems. The sample of the study is drawn by stratified systematic sampling technique to capture most representative sample on the basis of market capitalization. A total 12 years secondary data from 2000 to 2011 is used as the study period. This time frame is chosen because the Securities and Exchange Commission of Pakistan (SECP) issued corporate governance code in year 2002; moreover this time frame also covers the mandatory adoption of International Financial Reporting Standards (IFRSs) in 2005. The results of the study found that book value, earnings per share; quality corporate governance and real gross domestic product growth rate significantly determine the stock price. But the regression coefficients of inflation and money supply are statistically insignificant. The study also found that there is a positive and significant impact of the issuance of code of corporate governance and mandatory adoption of IFRSs on the value relevance of book value and earnings. This implies that the relevance of published financial statement has been increased for the investors.
Evaluating dynamics, sources and drivers of productivity growth at the farm level

This report measures and evaluates total factor productivity (TFP) of crop farms in the European Union (EU) in the period after the implementation of a series of important reforms of the EU Common Agricultural Policy (CAP). The analysis covers six EU Member states: the Czech Republic, France, Germany, Hungary, Poland and the United Kingdom. The data used in the analysis are based on the Farm Accountancy Data Network (FADN) data provided by the European Commission. To investigate sources of productivity growth, TFP is decomposed into three components – technical change, scale effect and technical efficiency. Technical change was found to be major source of productivity growth for most country samples for the two analysed periods. Technologies currently applied on crop farms were estimated to exhibit substantial economies of scale and therefore favour large-scale operations. However, economies of scale are not fully exploited which suggests the presence of some institutional constraints on farm growth. Large farms appear to be in a better position to exploit economies of scale; for West European countries covered in the report they were also found to exhibit larger persistent technical inefficiencies. Farm support payments were found to negatively influence crop farm productivity and efficiency of input use. More decoupled payments appear to be less distorting than other forms of support. A meta-level analysis of allocative efficiency shows that farms tend to be overcapitalised but to show relatively low allocative inefficiencies in their variable input use decisions. Substantial allocative inefficiencies appear also to exist in land and labour use. No significant economies of scope were found for the analysed crop production systems and levels of output aggregation. Farm flexibility was revealed to be determined mainly by the scale and convexity effects enabling cost efficient adjustments in the size of farm operations.
Entropy Management of Gaussian Stochastic Systems

Two approaches to the entropy management of Gaussian stochastic system are considered. The first approach is scalar and implements the concept of "growth points". In this case the problem of maximizing (increasing) or minimizing (decreasing) the system entropy is solved. The second approach is the vector management, allowing to ensure effective changing of the entropy of two-dimensional vector, the components of which are randomness and self-organization entropies. For vector control an optimization problem on the conditional extremum is formulated. This problem can be solved using penalty methods. It is shown that the vector management of entropy for a number of cases has advantages compared to the scalar management. Examples of entropy models of real stochastic systems are provided.
Perceptual and Ultrasound Articulatory Training Effects on English L2 Vowels Production by Italian Learners

— The American English contrast /ɑ-ʌ/ ( cop-cup ) is difficult to be produced by Italian learners since they realize L2-/ɑ-ʌ/ as L1-/ɔ-a/ respectively, due to differences in phonetic-phonological systems and also in grapheme-to-phoneme conversion rules. In this paper, we try to answer the following research questions: Can a short training improve the production of English /ɑ-ʌ/ by Italian learners? Is a perceptual training better than an articulatory (ultrasound - US) training? Thus, we compare a perceptual training with an US articulatory one to observe: 1) the effects of short trainings on L2-/ɑ-ʌ/ productions; 2) if the US articulatory training improves the pronunciation better than the perceptual training. In this pilot study, 9 Salento-Italian monolingual adults participated: 3 subjects performed a 1-hour perceptual training (ES-P); 3 subjects performed a 1-hour US training (ES-US); and 3 control subjects did not receive any training (CS). Verbal instructions about the phonetic properties of L2-/ɑ-ʌ/ and L1-/ɔ-a/ and their differences (representation on F1-F2 plane) were provided during both trainings. After these instructions, the ES-P group performed an identification training based on the High Variability Phonetic Training procedure, while the ES-US group performed the articulatory training, by means of US video of tongue gestures in L2-/ɑ-ʌ/ production and dynamic view of their own tongue movements and position using a probe under their chin. The acoustic data were analyzed and the first three formants were calculated. Independent t-tests were run to compare: 1) /ɑ-ʌ/ in pre- vs. post-test respectively; /ɑ-ʌ/ in pre- and post-test vs. L1-/a-ɔ/ respectively. Results show that in the pre-test all speakers realize L2-/ɑ-ʌ/ as L1-/ɔ-a/ respectively. Contrary to CS and ES-P groups, the ES-US group in the post-test differentiates the L2 vowels from those produced in the pre-test as well as from the L1 vowels, although only one ES-US subject produces both L2 vowels accurately. The articulatory training seems more effective than the perceptual one since it favors the production of vowels in the correct direction of L2 vowels and differently from the similar L1 vowels.
Aeroelastic Analysis of a Typical Section using Euler and Navier-Stokes Mesh-less Method

The main aim of this paper is to develop an efficient aeroelastic tool for predicting the flutter speed of a typical section in transonic regime. An implicit mesh-less method based on the Euler and Navier-Stokes equations are conducted to simulate the transonic fluid flow around an airfoil. This technique is applied directly to the differential form of the aerodynamic governing equations and the time integration is carried out using a dual-time implicit time discretization scheme. The capabilities of the flow solution method are demonstrated by flow computations around NACA0012 airfoil at different flow conditions. For structural dynamics simulation, a typical section model with pitching and plunging motion capability is considered. Finally, the aeroelastic analysis of the 2D model is performed by the consecutive simulation of both structural and aerodynamic domains. Also, the effect of viscosity and time interval choice between two structural and aerodynamic solvers on the flutter instability is studied. The comparison between the obtained results and those available in the literature shows the good accuracy of the present method.
Smooth Splicing: A Robust SNN-Based Method for Clustering High-Dimensional Data

Sharing nearest neighbor (SNN) is a novel metric measure of similarity, and it can conquer two hardships: the low similarities between samples and the different densities of classes. At present, there are two popular SNN similarity based clustering methods: JP clustering and SNN density based clustering. Their clustering results highly rely on the weighting value of the single edge, and thus they are very vulnerable. Motivated by the idea of smooth splicing in computing geometry, the authors design a novel SNN similarity based clustering algorithm within the structure of graph theory. Since it inherits complementary intensity-smoothness principle, its generalizing ability surpasses those of the previously mentioned two methods. The experiments on text datasets show its effectiveness.
Factors determining the concentration and chemical composition of particulate matter in the air of selected service facilities

The link between increased morbidity and mortality and increasing concentrations of particulate matter (PM) resulted in great attention being paid to the presence and physicochemical properties of PM in closed rooms, where people spends most of their time. The least recognized group of such indoor environments are small service facilities. The aim of this study was to identify factors which determine the concentration, chemical composition and sources of PM in the air of different service facilities: restaurant kitchen, printing office and beauty salon. The average PM concentration measured in the kitchen was 5-fold (PM 4 , particle fraction ≥ 4 μm) and 5.3-fold (TSP, total PM) greater than the average concentration of these PM fractions over the same period. During the same measurement period in the printing office and in the beauty salon, the mean PM concentration was 10- and 4-fold (PM 4 ) and 8- and 3-fold (TSP) respectively greater than the mean concentration of these PM fractions in outdoor air. In both facilities the main source of PM macro-components, especially organic carbon, were chemicals, which are normally used in such places - solvents, varnishes, paints, etc. The influence of some metals inflow from the outdoor air into indoor environment of those facilities was also recognized.
REDD in the red: palm oil could undermine carbon payment schemes

Mechanisms to reduce carbon emissions from deforestation and forest degradation (REDD) have been gaining momentum as a way to combat global warming, fund forest conservation, and deliver economic benefits to rural populations. However, the economic viability of REDD schemes will depend on the profitability of alternative land uses. Oil palm agriculture has become a major driver of tropical deforestation over the last few decades. Here, we model and compare the profitability of converting forest to oil palm versus conserving it for an REDD project. We show that converting a hectare of forest for palm oil production will be more profitable (yielding net present values of $3,835–$9,630) to land owners than preserving it for carbon credits ($614–$994), which are currently restricted to voluntary carbon markets. Giving REDD credits price parity with carbon credits traded in compliance markets would boost the profitability of avoided deforestation (up to $6,605). Unless post‐2012 global climate policies legitimize the trading of carbon credits from avoided deforestation, REDD will not be able to compete with oil palm agriculture or other similarly profitable human activities as an economically attractive land‐use option, in which case REDD will not be able to fulfill its primary function of avoiding deforestation.
A STUDY OF AGILE METHODOLOGIES AND ITS USE IN SOFTWARE DEVELOPMENT

Agile software design and development methodologies have been gaining ri-gorous attention in the software engineering research community since their early introduction in the mid-nineties in addition to being highly adopted by the software development industry. During the past forty years, new software development approaches were introduced to fit the new cultures of the software development companies. Most software companies nowadays aim to produce valuable software in short time period with minimal costs, and within unstable, changing environments. Agile Methodologies were thus introduced to meet the new requirements of the software development companies. This paper presents a review of three agile approaches including Extreme Programming, Agile Modeling, and SCRUM, describes the differences between them and recommends when to use them.