Miracle-dz/UniFAR-FTUs huggingface dataset:
Illicit drug detection using energy dispersive x-ray diffraction

Illicit drugs are imported into countries in myriad ways, including via the postal system and courier services. An automated system is required to detect drugs in parcels for which X-ray diffraction is a suitable technique as it is non-destructive, material specific and uses X-rays of sufficiently high energy to penetrate parcels containing a range of attenuating materials. A database has been constructed containing the measured powder diffraction profiles of several thousand materials likely to be found in parcels. These include drugs, cutting agents, packaging and other innocuous materials. A software model has been developed using these data to predict the diffraction profiles which would be obtained by X-ray diffraction systems with a range of suggested detector (high purity germanium, CZT and scintillation), source and collimation options. The aim of the model was to identify the most promising system geometries, which was done with the aid of multivariate analysis (MVA). The most promising systems were constructed and tested. The diffraction profiles of a range of materials have been measured and used to both validate the model and to identify the presence of drugs in sample packages.
Coverage properties of beta estimated prediction intervals for multimodal recovery rates

In this paper we use bootstrap methodology to achieve accurate estimated prediction intervals for recovery rates. In the framework of the LossCalc model, which is the Moody's KMV model to predict loss given default, a single beta distribution is usually assumed to model the behaviour of recovery rates and, hence, to construct prediction intervals. We evaluate the coverage properties of beta estimated prediction intervals for multimodal recovery rates. We carry out a simulation study, and our results show that bootstrap versions of beta mixture prediction intervals exhibit the best coverage properties.
Photolytic de‐activation of silver iodide as an ice‐forming nucleus

The rate at which the ice-nucleating ability of silver iodide decays when irradiated with the equivalent of strong sunlight has been determined by measuring the density of oriented ice crystals appearing on single crystals of silver iodide after various periods of exposure to a mercury-arc lamp. Wavelengths greater than 4,400 A cause very little photolysis and decay of nucleation. The ice-crystal density decreases 10- to 20-fold after the silver iodide has been exposed to the equivalent of one hour's strong sunlight; this result is in fair agreement with the findings of the Australian workers where the activity of silver-iodide smoke falls by 1 to 2 orders of magnitude after one hour in the atmosphere in sunlight.
Effluent stellar pulsation

Near-discontinuities in the density of a star, such as that encountered in the transition between a chromosphere and a corona, reflect acoustic waves and thereby partially contain them within the star. These reflections help to establish a resonant acoustic cavity with discrete characteristic frequencies, even for modes with frequencies above the acoustic cutoff frequency. Reflection is not complete, however, and energy propagates away from the star, contributing to the decay of the mode. Nevertheless, for coronae with temperatures of order 10 to the 6th K, the contribution that such decay is likely to make to the line width in a power spectrum of the oscillations is substantially less than the frequency separation between modes of adjacent order and like degree. Therefore, in that case, characteristic acoustic frequencies exist. A physical discussion of the phenomena is presented, and is illustrated by a simple analytical model. The results are compared with numerical stability calculations of high-order radial modes of a model of the sun. 33 refs.
Towards increased speed computations in 3D moving eddy current finite element modelling

A finite element scheme used to model eddy current problems with motional velocity is described here. The formulation is a variation on the A-/spl psi/ method. An additional Minkowski-transformation term is required to take into account the velocity. However, computational instability arises when the velocity increases to the point that the first order velocity terms severely dominate the second order diffusion terms. The method presented here uses upwinding to help regain stability. An additional degree of stability is inserted at higher speeds by using a lower speed result as an initial vector. This leads to a reduced permeability in saturated regions which counterbalances to some extent the increase in velocity. The method is validated by experimental measurement.
Distributed geolocation algorithm in mobile ad hoc networks using received signal strength differences

Future military wireless communication in a battlefield will be mobile ad hoc in nature. The ability to geolocate and track both friendly forces and enemies is very important in military command and control operations. However, current mobile ad hoc networks (MANET) have no capabilities to geolocate radio emitters that belong to enemy mobile ad hoc networks. This paper presents a distributed geolocation algorithm using received signal strength differences to geolocate enemy radio emitters by leveraging friendly force MANET infrastructure, and proposes a communication protocol for radio emitter geolocation applications. An enemy's radio emitter signal is detected, and its signal strength is measured by the nodes in a friendly mobile ad hoc network. The identity of the enemy radio emitter is extracted from the decoded message header of the medium access control layer. By correlating and associating the enemy's radio emitter identity with its received signal strength, the enemy radio emitter is identified. The enemy's radio emitter identity and its received signal strength are distributed and shared among friendly mobile ad hoc nodes. Using received signal strength differences, a master friendly node can calculate the enemy's radio emitter geolocation, and build a recognized MANET picture (RMP). This MANET picture is then distributed to all friendly nodes for effective command and control operations. An advantage of this method is that mobile ad hoc nodes do not need special RF antennas to geolocate the enemy radio emitter as conventional electronic warfare techniques do. MATLAB-based simulations are presented to evaluate the accuracy and reliability of the proposed distributed geolocation algorithm under different MANET placements.
A fibre-optic temperature sensor based on the deposition of a thermochromic material on an adiabatic taper

A fibre-optic sensor has been developed for the measurement of temperature, especially of liquids. The device is conceived as part of an all-optical CTD probe for the control of the physical parameters of a marine medium. The dependence on temperature of the optical properties (specifically, absorbance) of a thermochromic material, namely lophine (2,4,5-triphenylimidazole), is the basis of the sensor. The sensor presents some significant differences with respect to other similar sensors proposed in the literature: the use of adiabatic, long, tapered optical fibres with adjustable geometric parameters; the use of LED illumination in the 800? nm range; improvements in the deposition technique, etc. The sensors show a linear behaviour over the desired temperature range, and their sensitivity is high. Also, the dependence of the response of the sensor with variations of the geometry of the tapers is discussed. Specifically, we have performed measurements with different diameters of the taper waist, and we show the dependence of the slope of the response curve with that parameter.
A VLA Survey for Compact Radio Sources in the Galactic Center

The scattering diameters of Sgr A* and several nearby OH masers (≈1″ at 1 GHz) indicate that a region of enhanced scattering is along the line of sight to the Galactic center. This region of enhanced scattering implies that radio pulsars in or beyond the Galactic center will suffer pulse broadening of hundreds of seconds at 1 GHz. We have used the VLA at 1.4 GHz to survey the inner 2° of the Galactic center for radio pulsar candidates. Because of the large pulse broadening suffered by Galactic center radio pulsars, our strategy has been to identify compact radio sources, without regard to whether they are pulsed radio sources. We describe our survey and present the catalog of 170 sources. Comparison with other radio surveys of the area shows that just over half of these sources have not been detected previously; this same comparison reveals 29 sources that are not in higher frequency surveys, suggesting that the sources are either variable or steep spectrum, and a comparable number of sources in other surveys that should have been detected in this survey but were not. Comparison with infrared surveys shows that 59 (35%) sources have infrared counterparts and are likely to be H II regions. On the basis of the number of sources as yet unidentified, we estimate that there could have been no more than roughly 104-105 supernovae in the past several million years in the Galactic center. This estimate is consistent with the number required to produce the X-ray-emitting plasma in the Galactic center and is marginally consistent with that required to explain the 1.8 MeV emission from 26Al.
Adolescents' problematic internet and smartphone use in (cyber)bullying experiences: A network analysis.

BACKGROUND This study investigates both offline and online bullying perpetration and victimization in association with problematic internet use (PIU) and problematic smartphone use (PSU), while also considering the related psychosocial difficulties. METHODS A total of 3939 adolescents (49.4% boys, aged 13-15 years) from a representative sample of schools in Slovakia was obtained from the Health Behavior in School-aged Children (HBSC) project in 2018. Due to the lack of similar complex research and the expected mutual associations among the constructs, we compared exploratory network models that provided separate estimates for boys and girls. RESULTS The constructs formed similarly clustered networks for both genders, with a few notable differences. Unlike PIU, PSU was not associated with bullying experiences in boys or girls; however, PSU and PIU were partially related in girls. Bullying experiences formed a strong cluster in both networks. Two strong bridges were identified, and they are potential candidates for intervention in both boys and girls: first, traditional bullying victimization connected the cluster of bullying experiences to psychosocial difficulties; and, second, frequently missing sleep or meals due to internet use (behavioral salience) that is connected to the bullying cluster with PIU. CONCLUSIONS The findings offer an indication for the preventive and interventive work of practitioners who deal with adolescents, as well as complex gender comparisons for the mutual relations of problematic internet and smartphone use, bullying experiences, and the psychosocial difficulties of youth. This study provides evidence that problematic digital media can play a role in bullying experiences irrespective of whether bullying happens offline or online.
Analysis of The Effectiveness of Implementation SAP R/3 In PT. ABC

This research analyses the effectiveness of SAP R/3 toward user satisfaction in using the application. The research is in PT ABC, manufactured in paper and tissue products. The research questions of this research are: "Is there any gap between the user expectation about the effectiveness of the application and the application's performance? Are some factors, which are integrated data, reliable report, processing time, and flow of information between departments significantly, affecting the user satisfaction in using SAP R/3? " The data for this research is collected using questionnaires to the employees of four departments in PT. ABC, which are the Sales and Marketing Department, Finance and Accounting Department, Production Department, and Logistics Department. The analysis used in the research is Gap Analysis and Multiple Regression Analysis. The results of this research are: "There is a gap between the user expectation about the effectiveness of the application and the application performance. There are three factors that significantly affect user satisfaction in using SAP R/3, which are integrated data, reliable report, and processing time. " The benefit of the research is the effectiveness of the SAP R/3 implemented in PT. ABC. The research result can be used as a reference for further improvement of SAP R/3.The research results can be used as a reference for other companies or organizations implementing SAP R/3.
Icaritin inhibits oxidative stress in murine astrocytes by binding to Orai1 to block store‐operated calcium channel

Previous study has shown that icaritin (ICT) has meaningful protective effect on cerebral ischemic stroke, and this study aimed to investigate its mechanism from the aspect of protecting astrocytes from oxidative stress. Murine primary astrocytes were pretreated by ICT and exposed to H2O2 to induce oxidative stress. The results indicated that ICT inhibited H2O2‐induced astrocytes apoptosis, decreased Bax and cleaved caspase‐3, and increased Bcl‐2. In addition, ICT inhibited H2O2‐induced oxidative stress, increased mitochondrial membrane potential (ΔΨm), and maintained mitochondrial morphology. ICT decreased the synthesis of malondialdehyde and increased the activity of glutathione peroxidase, catalase, and superoxide dismutase. Moreover, ICT suppressed the transient and resting intracellular Ca2+ overload. Further investigation revealed that ICT could target the combination with Orai1 to block store‐operated calcium channel induced by H2O2. However, ICT did not enhance the protective effect of RO2959, a selective blocker of Orai1. These results indicate that ICT can play a neuroprotective role against oxidative stress injury by binding to Orai1 to block SOCC.
L1 Adaptive Output Feedback Controller for a Class of Nonlinear Systems

This paper presents an extension of the L1 adaptive output feedback controller to a class of nonlinear systems where nonlinearities satisfy a semiglobal Lipschitz condition. The control algorithm consists of an output predictor which is designed to predict the system’s output with arbitrary accuracy, and a control law which is used to control the predictor output instead of the actual system’s output. It is shown that the adaptive output feedback controller ensures uniformly bounded output tracking for the system. The performance bound can be systematically improved by reducing the step size of integration. Numerical simulation results are provided to illustrate the algorithm’s performance.
Solar-cycle variations in the spectrum of supergranulation

Using local helioseismology, we construct maps of the horizontal divergence of the velocity field near the solar surface and study the spectrum of solar supergranulation during the period from 1996 to 2002. Supergranulation oscillates and propagates like a wave interference pattern. The variations of the oscillation frequency with latitude and time are less than 5%. We find significant solar-cycle variations in the lifetime and the anisotropic distribution of power. We also measure the time-dependent zonal and meridional flows that advect supergranules.To search for other articles by the author(s) go to: http://adsabs.harvard. edu/abstract_service. html
Review of the Theoretical Framework of "Non-Cognitive Ability"(2012-2020)

: In today's general environment of population aging, economic growth entering the "new normal" and increasingly fierce social competition, the traditional human capital theory urgently needs to be improved, and all sectors of society have increasingly recognized the importance of "non-cognitive ability". By combing and summarizing the relevant research literature of non-cognitive ability at home and abroad, this paper puts forward the prospect of building a theoretical framework of non-cognitive ability based on the concept of non-cognitive ability, importance, formative factors and development mechanism, and measurement method
Perceptions of Smallholder Rice Farmers on Traditional and Conventional Weather Forecasting in Zanzibar, Tanzania

This paper assesses the perceptions of the smallholder rice farmers in Zanzibar on the use of conventional and indigenous knowledge (IK) for seasonal weather forecasting and farming decisions. It draws data from a study that was conducted in two rice fields in Central district, Unguja, and four rice fields in Micheweni district, Pemba. The paper mainly employs qualitative data from focus group discussions and interviews. The results reveal that farmers, particularly from rain-fed rice fields, have limited access to conventional seasonal weather forecasts, and thus rely on the knowledge of traditional weather forecasting. This is ascribed to their negative perceptions on conventional seasonal weather forecasts, limited access to extension services, and limited access to media, such as television and radio that provide weather information, which is attributed to low rural electrification and poverty. The results also showed that smallholder rice farmers in the islands use their own indigenous knowledge to forecast weather and utilise it for the preparation of fields, planting and harvesting of rice. The study highlights that, recent fluctuations in rice production is attributable to the variability of rainfall, rainfall seasons, and incidences of extreme floods. This illustrate the challenges of both conventional and traditional weather forecasting systems, and underscore the need and importance of integrating traditional and conventional weather forecasting to increase access to conventional weather forecasting to boost resilience to the impacts of current and future climate changes.
The Application of Multimodal Discourse Theory in the Teaching of Business English Writing Course

: The deep integration of modern information technology and education has brought opportunities for the development of business English teaching in higher vocational college. Teachers can make use of multi-modality and media to create multimodal situational contexts and cultural contexts, with attention paid to the synergy between multimodal symbols. Taking the module of business English course in a vocational college in Guangzhou as an example, teachers are expected to use a multimodal teaching approach that can help students build an active, effective and interactive learning process. The method used in this research is classroom action research in which both qualitative and quantitative data collection techniques were implemented in two classes, which aim at (1) tracking the improvement of students’ skills in both writing competence and business practice; and (2) finding the synergy among different modalities when efficiency could be successfully achieved in a business writing class. Results showed that when such measures as multimodal teaching were taken, this approach could facilitate teachers to improve students' capability in business English writing, promote the interaction between teachers and students, improve students' multimodal reading ability and critical thinking, and enhance students' awareness of cross-cultural business communication. To achieve the best effect, the synergy among different modalities should be highly emphasized.
Negative differential gain due to many body effects in self-assembled quantum dot lasers

The gain spectrum of a quantum dot laser operating at 1300 nm is studied at high carrier densities, corresponding to dot occupancies of ∼8 e-h pairs per quantum dot. A reduction in peak gain with increasing carrier density is observed, attributed to the saturation of peak gain, yet the continuous increase in dephasing acting to broaden the individual quantum dot transitions.
Design of a Dual-Mode Tunable Wide-Bandstop Filter with Controllable Bandwidth

Abstract In this article, a compact dual-mode tunable wide bandstop filter with controllable bandwidth is presented. The proposed filter consists of an open-loop stepped-impedance resonator with a T open stub loaded. Varactor diodes Cv1 and Cv2 are loaded at two ends of the stepped-impedance resonator and the loaded T stub, respectively. By properly adjusting the capacitances Cv1 and Cv2 of the varactor diodes, the constant fractional bandwidth and constant absolute bandwidth can be achieved, respectively. A new dual-mode tunable wide bandstop filter with 61.0% constant fractional bandwidth and 2.0-GHz constant absolute bandwidth has been designed and fabricated to verify the validity of the proposed method. The measured results are in good agreement with the electromagnetic simulation.
Prediction Model for Shallow‐Water Sound Transmission

For predicting the transmission loss to long ranges in shallow water with downward refraction, when only a fragmentary knowledge about the bottom is available, a theoretical model is derived leading to a particularly simple expression for the loss in terms of the water depth, velocity gradient, and bottom‐reflection loss at small grazing angles. This latter quantity, for which no measurements are extant, is approximated through computed curves of reflection loss at the boundary of a semi‐infinite absorptive fluid. A test of the model is provided by two sets of field data. One consists of recent measurements by NEL at 1.5 kHz, along with core‐sample measurement of bottom density and sound velocity, in several Pacific Ocean areas. The other comprises a hitherto‐unpublished transmission survey at 12 kHz made in 1944 by WHOI around our East and Gulf coasts. For this mass of data, the only information about the bottom is contained in words like “mud” and “sand. ” Reasonable agreement with both sets of data is f.
AN INTRINSIC CORRELATION BETWEEN GRB OPTICAL/UV AFTERGLOW BRIGHTNESS AND DECAY RATE

We examine a sample of 47 Swift/UVOT long Gamma-ray Burst light curves. Using the restframe light curves we find a correlation between the logarith mic luminosity determined at 200s, log L200s, and average decay rate measured from 200s onwards, α>200s. The Spearman rank coefficient for the correlation is -0.54 at a probability of 99.99 % (3.9σ ). We find the log L 200s α>200s correlation to be an intrinsic property of long GRBs and discuss three potential causes. Of these three scenarios, we are able to exclude the correlation as re sulting naturally from the standard afterglow model. However, we cannot presently exclude or distinguish between the other two possibilities. The first scenario is that there is some prope rty of the central engine, outflow or external medium that affects the rate of energy release in such a way that the bright afterglows release their energy more quickly than the fainter afterglows. Alternatively the correlation may be produced by variation of the observers viewing angle, with observers at large viewing angles observing fainter and slower light curves.