Miracle-dz/UniFAR-FTUs huggingface dataset:
Mid-Holocene drylands: A multi-model analysis using Paleoclimate Modelling Intercomparison Project Phase III (PMIP3) simulations

This study examines changes in aridity levels during the mid-Holocene (approximately 6000 cal. yr ago) using multi-model simulations from the Paleoclimate Modelling Intercomparison Project Phase III. Overall, there is little difference in the total area of drylands from the preindustrial period; global drylands are 8% wetter than during the preindustrial period as measured by an aridity index; and 16% of preindustrial drylands convert to a wetter climate subtype, double the sum of zones that are replaced by a drier category. Considerable variations are present among regions with major contractions of each dryland subtype from northern Africa to South Asia and the main expansions of arid, semiarid, and dry subhumid climates in southern hemisphere continents. The difference in precipitation is the leading factor of the aforementioned changes. The second factor is the altered potential evapotranspiration as mainly induced by relative humidity, which contributes to additional aridity changes in a same direction as precipitation does. The collective effects of precipitation and relative humidity account for more than 80% of the dryland variations. In comparison, the simulated aridity change is in reasonable agreement with reconstructions, while there are model–data discrepancies for Australia and uncertainties across proxies for southern Africa.
A modified SLM technique for PAPR reduction in OFDM systems by using a novel phase sequence

ABSTRACT Orthogonal frequency division multiplexing (OFDM) as a basic technique has remarkable influences on communication systems performance. However, the high peak-to-average power ratio (PAPR) of the OFDM signal is its detrimental effect. One of the popular techniques for PAPR reduction is selected mapping (SLM), where an amount of side information (SI) is exchanged undesirably. Swapped SLM (S-SLM) was proposed to reduce the computational complexity of SLM method. In this paper, in order to improve the performance both in terms of PAPR reduction and complexity, we introduce Vandermonde matrix as a novel phase sequence for the S-SLM scheme in OFDM systems, also by using an inter-leaver. In the proposed technique, there is no need to send SI and simulation results show substantial PAPR reduction in comparison with the conventional SLM and S-SLM techniques.
COMPARISON OF MATHEMATICAL MODELS FOR TRANSIENT STABILITY CALCULATION IN PSASPAND PSS/E AND CORRESPONDING CALCULATION RESULTS

The mathematical models for transient stability calculation in PSASP and PSS/E respectively developed by China Electric Power Research Institute and PTI Inc., in USA are compared and analyzed. By means of the simulations fo two test systems the calculation results of power flow and tha of the transient stability by the two models are compared, the comparison results show that the results from the two models are close on and the reasons causing the distinction are explained.
Role of Pore and Pore‐Throat Distributions in Controlling Permeability in Heterogeneous Mineral Dissolution and Precipitation Scenarios

Mineral dissolution and precipitation reactions can significantly alter the porosity and permeability of porous media. While porosity generally increases with dissolution and decreases with precipitation, permeability is controlled by the spatial locations of reactions in discrete pores and pore throats and in the greater pore network. Geochemical reactions have been observed to occur both uniformly and nonuniformly in porous media, driven by parameters such as mineral distribution, grain size, and Peclet and Damkohler numbers. Pore network modeling can be used to simulate the impact of pore‐scale alterations on permeability, requiring only pore and pore‐throat size distributions and pore connectivity. Here, the impact of variations in pore and pore‐throat size distributions on reactive permeability for uniform and nonuniform spatial distributions of reactions is evaluated. A series of pore network models are created and populated with pore and pore‐throat size distributions of varying types (skewed, normal, and uniform) to represent differences in network topology and characterization methods. The impacts of these distributions on reactive permeability are then simulated for uniform and nonuniform reaction conditions by increasing or decreasing pore and pore‐throat sizes in a prescribed manner to reflect dissolution and precipitation, respectively. Overall, simulations reveal that porosity‐permeability evolution varies with reaction scenario and is qualitatively consistent for the different pore and pore‐throat size distributions. Common macroscopic porosity‐permeability relationships work well for some reaction scenarios but are unable to reflect size‐dependent reactions. A new modified version of the Verma‐Pruess relationship is created and able to successfully reflect the porosity‐permeability evolution for size‐dependent reactions.
Anisotropic Octrees: a Tool for Fast Normals Estimation on Unorganized Point Clouds

With the recent advances in remote sensing of objects and environments, point cloud processing has become a major ﬁeld of study. Three-dimensional point cloud collected with remote sensing instruments may be very large, containing up to several tens of billions of points. This imposes the use for efﬁcient and automatic algorithms to extract geometric or structural elements of the scanned surfaces. In this paper, we focus on the estimation of normal directions in an unorganized point cloud and provide a curvature indicator. We avoid point-wise operations to accelerate the running time for normals estimation. Instead, our method rely on an innovative anisotropic partitioning of the point cloud using an octree structure guided by the geometric complexity of the data and generates patches of points. These patches are then approximated by a quadratic surface in order to estimate the normal directions and curvatures. Our method has been applied to six models of various types presenting different characteristics and performs, in average, 2.65 times faster than multi-threads implementations available in current pieces of software. The results obtained are a compromise between running time efﬁciency and normals accuracy. Moreover, this work opens up promising perspectives and can be easily inserted in wide range of workﬂows.
Assessment of thermal overheating in free-running buildings in Cairo

Assessing human health under climate change in hot climates is of particular importance in the Middle East. Cairo is one of those cities that have an estimated 2018 population as high as 13 million, with a metropolitan population of 21 million, which makes it the largest city in Africa and the Middle East. In and around Cairo, many of the summer seasonal deaths are blamed on human discomfort due to anthropogenic climate change. High urban population density, urban heat island effect, cramped living conditions including housing, schools and prisons are all reasons to the increase of heat-related health problems in Cairo. Therefore, this initial study investigates and maps overheating in free-running residential buildings in Cairo. The study follows a combined, monitoring and observational assessment of the 2015 heat wave (19-day event) in Egypt. Using surface urban heat island maps, representative urban areas were determined and field measurements were carried out to assess indoor air temperatures and relative humidity. This was followed by observational field visits and interaction with local citizens to document the impacts and adaptation measures corresponding to overheating. The paper provides insights on indoor human discomfort with a focus on physical and non-physical heat stress reasons during climate extremes. The study provides initial insights on thermal comfort that can prompt local professionals and governments to address overheating and thermal stress in free-running residential buildings.
Poor development control as flood vulnerability factor in Suleja, Nigeria

Like many developing countries over the decade, Nigeria has experienced rapid urbanization associated with numerous problems such as, among others, improper waste management practices, building development regulations and standards contraventions, environmental pollution, overcrowding, and flooding. In light of the foregoing, this article examines the use and effectiveness of development control measures in addressing flood vulnerability in Suleja, Nigeria. In carrying out this study, buildings vulnerable to flooding were identified and factors influencing their vulnerability as well as the implications of non-adherence to development control measures were also determined. As part of this study, a total of 278 questionnaires were administered to adult residents of the study area, using multi-stage sampling techniques. A quick bird’s eye image of 15-meter resolution was used to identify and map out the buildings in the area considered vulnerable to flooding, using a 15-meter setback from the river banks. The study reveals that 799 buildings were built in contravention of building development standards and regulations in Suleja, while indiscriminate solid waste disposal methods were found to be strong factors influencing vulnerability to flooding in the area. The study also revealed that 47% of drainages in Suleja are blocked with indiscriminately disposed solid waste materials. The study recommends that an improved solid waste management system for Suleja be put in place to stem the imminent outbreak of diseases associated with poor environmental management and that development control measures be strictly enforced by the Niger State Urban Development Board.
Research and recent development of image fusion at pixel level

This paper introduced the principles based on image fusion at pixel level in detail,analysed synthetically and summed up the present routine algorithm of image fusion at pixel level and evaluation criteria of its quality.It pointed out the recent development of image fusion at pixel level,and discussed the development tendency of technique of image fusion at pixel level.
Treating paraffin deposits in producing oil wells

Paraffin deposition has been a problem for operators in many areas since the beginning of petroleum production from wells. An extensive literature search on paraffin problems and methods of control has been carried out, and contact was made with companies which provide chemicals to aid in the treatment of paraffin problems. A discussion of the nature of paraffins and the mechanisms of this deposition is presented. The methods of prevention and treatment of paraffin problems are summarized. Suggested procedures for handling paraffin problems are provided. Suggestions for areas of further research testing are given.
he Effects of Climate Change on Native Icelandic Plants: A Morphometric Analysis

This study seeks to evaluate the morphology of three native Icelandic plant species, Alchemilla alpina, Arabidopsis petraea, and Silene uniflora, in order to determine if changing climatic conditions have had an effect on Icelandic vegetation during the twentieth century. I measured herbarium specimens collected during a time period before 1950, and during the period from the late 1960s to the present. Using traditional morphometrics methods, I searched for changes in morphological traits such as plant height, leaf length to width ratio, and leaf size, then performed two-tailed t-tests to analyze the results of the analyses. I found significant changes in the plant height and in leaf length to width ratio of two of the species, but no significant differences in leaf area between the pre-1950 and post-1950 groups. Based on these results, I believe that future studies of this kind could benefit from more extensive data collection and contribute to our knowledge of the influence of climate change on sub-Arctic vegetation and its consequences.
Significant Impact of Heat Supply From the Gulf Stream on a “Superbomb” Cyclone in January 2018

On 4 January 2018, an extremely rapidly developing extratropical cyclone (“superbomb” cyclone) appeared over the Gulf Stream. To clarify the key process of the intensification of the superbomb cyclone, we specifically examined the role of heat supply from the Gulf Stream by performing cloud‐resolving numerical experiments. When the cyclone rapidly developed, sensible and latent heat fluxes from the warm current predominated around the cold conveyor belt (CCB) of the cyclone. These fluxes created a convectively unstable layer near the surface. When the instability was released around the cyclone center, latent heating (LH) occurred. The increased LH further intensified the cyclone and its associated CCB. These findings indicate that the positive feedback process between the CCB and LH played a key role in intensification over the Gulf Stream. In this way, the heat supply from the Gulf Stream significantly impacted the development of the superbomb cyclone.
Age and origin of leaf wax n-alkanes in fluvial sediment–paleosol sequences and implications for paleoenvironmental reconstructions

Abstract. Leaf wax n-alkanes are increasingly used for quantitative paleoenvironmental reconstructions. However, this is complicated in sediment archives with associated hydrological catchments since the stored n-alkanes can have different ages and origins. 14C dating of the n-alkanes yields independent age information for these proxies, allowing their correct paleoenvironmental interpretation. This also holds true for fluvial sediment–paleosol sequences (FSPSs) that integrate two different n-alkane signals: (i) a catchment signal in fluvial sediments and (ii) an on-site signal from local biomass that increasingly dominates (paleo)soils with time. Therefore, the age and origin of n-alkanes in FSPSs are complex: in fluvial sediment layers they can be pre-aged and reworked when originating from eroded catchment soils or from organic-rich sediment rocks in the catchment. In (paleo)soils, besides an inherited contribution from the catchment, they were formed on-site by local biomass during pedogenesis. Depending on the different relative contributions from these sources, the n-alkane signal from an FSPS shows variable age offsets between its formation and final deposition. During this study, we applied compound-class 14C dating to n-alkanes from an FSPS along the upper Alazani in eastern Georgia. Our results show that preheating the n-alkanes with 120 ∘C for 8 h before 14C dating effectively removed the shorter chains (<C25) that partly originate from n-alkanes from Jurassic black clay shales in the upper catchment. The remaining petrogenic contributions on the longer chains (≥C25) were corrected for by using a constant correction factor that was based on the n-alkane concentrations in a black clay shale sample from the upper catchment. Due to different degrees of pre-aging and reworking, the corrected leaf wax n-alkane ages still indicate relatively large age offsets between n-alkane formation and deposition: while intensively developed (paleo)soils showed no age offsets due to a dominance of leaf wax n-alkanes produced on-site, less intensively developed paleosols showed much larger age offsets due to larger proportions of inherited leaf wax n-alkanes from the fluvial parent material. Accordingly, age offsets in nonpedogenic fluvial sediments were largest and strongly increased after ∼4 ka cal BP. The leaf wax n-alkane homolog distribution from intensively developed (paleo)soils indicates a local dominance of grasses and herbs throughout the Holocene, which was most likely caused by anthropogenic activity. The leaf wax n-alkanes from fluvial sediments show a dominance of deciduous trees and shrubs as well as grasses and herbs in different parts of the catchment between ∼8 and ∼5.6 ka cal BP. Since no older deciduous tree- or shrub-derived n-alkanes were dated, this seems to confirm a delayed regional postglacial reforestation of parts of the catchment compared with western and central Europe.
Multi-model fusion modeling method for process industries soft sensor

The paper summarizes research progress of the multi-model fusion modeling method for process industries soft senor. According to the difference of sub-models,the multi-model fusion modeling method can be divided into data driven fusion modeling method and semi-parametric modeling method. The design ideas and research status of the data driven fusion modeling method and semi-parametric modeling method are presented,their advantages and disadvantages are analyzed,and corresponding improvement directions are proposed. According to different data processing methods,the data driven fusion modeling method can be divided into ensemble learning and cluster analysis. According to different types of model structures,semi-parametric modeling method is divided into serial and parallel structure. In the end,the future research directions of multi-model fusion modeling are presented. It is expected that breakthrough can be made in improvement of data driven models fusion technology,advancement of semi-parametric models generalization ability,and solution of dual-rate sampling. Developing soft sensor models based on multi-source information fusion by using the multi-model fusion modeling method is an effective way to realize online estimation of variables which are difficult to measure in process industries.
Full-waveform matching of VP and VS models from surface waves

The analysis of surface wave dispersion curves (DCs) is widely used for near-surface S-wave velocity (VS) reconstruction. However, a comprehensive characterization of the near-surface requires also the estimation of P-wave velocity (VP). We focus on the estimation of both VS and VP models from surface waves using a direct data transform approach. We estimate a relationship between the wavelength of the fundamental mode of surface waves and the investigation depth and we use it to directly transform the DCs into VS and VP models in laterally varying sites. We apply the workflow to a real data set acquired on a known test site. The accuracy of such reconstruction is validated by a waveform comparison between field data and synthetic data obtained by performing elastic numerical simulations on the estimated VP and VS models. The uncertainties on the estimated velocity models are also computed.
Global Research Productivity in the Field of Dermatoglyphics: A Quantitative Assessment of 50 Years of Journal Article Output

Dermatoglyphics is a scientific field that deals with the analysis of dermal ridge patterns on the digits of fingers, the palms of hands, and the soles of feet and is used as a mean of personal identification. The aim of this article is to assess the research productivity in the area of dermatoglyphics. The Scopus multidisciplinary database was searched for articles published between 1964 and 2013 in which one or more of the following Medical Subject Headings (MeSH) were used in either the title, abstract, or keyword fields: dermatoglyphics, plantar prints, and fingerprints. An analysis of 8,546 documents in dermatoglyphics in terms of types of documents published and language of publication; annual growth of papers; most prolifically publishing countries, institutions, authors, and journals; most cited papers; h-index; and citation status has been provided.
The study on automitic classification of digital documents of scientific papers

Since scientific papers are usually semi-structural documents,a hierarchy classification model based on the metadata of scientific papers is proposed,where the metadata include the titles,sets,abstracts and so on.Experiments show the precision of the classification based on the metadata of papers is close to that of the classification based on the full text of papers.Furthermore,the classification precisions are better than the best known classification algorithm if the papers are classified based on taxonomy of application domains as follows: first,the metadata are used to classify paper roughly based on the higher levels of taxonomy,then full texts are utilized to classify these papers on the lower levels of taxonomy.Since the size of metadata is less than that of full text and the number of papers classified in a subclass is less than that of total number of papers,the new model enhances the efficiency of paper classification when the number of classes is bigger and the documents are distributed averagely in the given taxonomy
Visual Feedback System for Intuitive Comprehension of Self-movement and Sensor Data for Effective Motor Learning

Information feedback systems for motor learning have been widely studied. Means of providing feedback can be divided into two approaches: auditory and visual. Audio information can provide feedback without preventing training motions a trainee makes when moving (Effenberg et al., 2011). However, due to the intrinsic feature of sound, i.e., that is onedimensional temporal data, the information it can express is quite limited. Visual feedback has also been widely studied (Guadagnoli et al., 2002; Wieringen et al., 1989). Feedback of this type can provide a great deal of information through the use of visual information. For example, Chua et al. have developed a training system in a VR environment (Chua et al., 2003). The system uses a motion capturing technique to capture a trainee’s movements and shows the corresponding trainer’s movements. Choi et al., have proposed a system that estimates motion proficiency on the basis of motion capture data (Choi et al., 2008). However, though visual information may enhance motor learning efficacy, there are two problems that make it difficult for most existing visual feedback systems to be used in practice. One problem is in setting. The aforementioned systems employ motion capture techniques to obtain human movement. The overhead for setting mocap systems and training site restrictions deteriorate the systems’ efficacy. The other problem is in the timing of visual feedbacks. The simplest visual feedback system is training in front of a mirror. In this case, the trainee has to get visual feedback while he or she is moving, which disrupts practice. Another simple visual feedback system is capturing and watching a video. In this case, the temporal gap between capturing and watching gets longer, and this degrades feedback efficacy. In recent years, small sensors have been developed that enable information of various types such as surface electromyography (EMG), cardiac rate, and resPC Trainee's motion with delay Reference motion in synchronization with current motion
Simulating variation in order to learn classroom management

Abstract Classroom management is an important part of learning to be a teacher. The variation theory of learning provides the insight that it is important to vary the critical aspects of any task or subject that is to be learned. Simulation technology is useful in order to provide a controlled environment for that variation, and text as a medium gives the opportunity to control exactly what aspects are presented to the learner. This study shows that text-based simulation has the potential to help the learner discern critical aspects of classroom management.