Miracle-dz/UniFAR-FTUs huggingface dataset:
Adaptive repetitive control of PWM inverters for very low THD AC-voltage regulation with unknown loads

An adaptive repetitive control scheme is proposed and applied to the control of a pulsewidth-modulated (PWM) inverter used in a high-performance AC power supply. The proposed control scheme can adaptively eliminate periodic distortions caused by unknown periodic load disturbances in an AC power supply. The proposed adaptive repetitive controller consists of a voltage regulator using state feedback control, a repetitive controller with tuning parameters and an adaptive controller with a recursive least-squares estimator (LSE). This adaptive repetitive controller designed for AC voltage regulation has been realized using a single-chip digital signal processor (DSP) TMS320C14 from Texas Instruments. Experimental verification has been carried out on a 2 kVA PWM inverter. Simulation and experimental results show that the DSP-based adaptive repetitive controller can achieve both good dynamic response and low total harmonic distortion (THD) under large-load disturbances and uncertainties.
Modelling the extreme precipitation event over Madeira Island on 20 February 2010

Abstract. In the morning of the 20 February of 2010 an extreme precipitation event occurred over Madeira Island. This event triggered several flash floods and mudslides in the southern parts of the island, resulting in 42 confirmed deaths, 100 injured, and at least 8 people still missing. These extreme weather conditions were associated to a weather frontal system moving northeastwards embedded in a low pressure area centered in the Azores archipelago. This storm was one in a series of such storms that affected Portugal, Spain, Morocco and the Canary islands causing flooding and strong winds. These storms were bolstered by an unusually strong sea surface temperature gradient across the Atlantic Ocean. In this study, the WRF model is used to evaluate the intensity and predictability of this precipitation extreme event over the island. The synoptic/orographic nature of the precipitation is also evaluated, as well as the sensitivity of the model to horizontal resolution and cumulus parameterization. Orography was found to be the main factor explaining the occurrence, amplitude and phase of precipitation over the Island.
Renegotiation and Contracts with Moral Hazard and Persistent Private Information ∗

How does renegotiation shape contracts between a principal and an agent subject to persistent private information and moral hazard? This paper introduces a concept of renegotiation-proofness, which adapts to stochastic games the concepts of weak renegotiation-proofness and internal consistency by exploiting natural comparisons across states. When the agent has exponential utility and cost of effort, each separating renegotiation-proof contract is characterized by a single “sensitivity” parameter. The optimal contract among those always causes immiserization. Reducing the agent’s cost of effort can harm the principal by increasing the tension between moral hazard and reporting problems. For the constructed contracts, truthful reporting is optimal on but also off the equilibrium path. ∗Northwestern University. I am particularly grateful to Alessandro Pavan, Hector Chade, Roozbeh Hosseini, Jean Tirole, and Mehmet Ekmekci, Daniel Garrett, Christian Hellwig, Johannes Hörner, Parag Pathak, Francisco Ruiz-Aliseda, Larry Samuelson, Ilya Segal, Itai Sher, Juuso Toikka, Mike Whinston, and seminar audiences at Arizona State University, the University of Minnesota, Northwestern University, the University of Tokyo, Yale University, the Ecole Polytechnique and the Ecole HEC, Stanford University, the Northwestern CSIO-Toulouse IDEI 2011 Conference, Ohio State University, the SAET 2011 Conference, the ESSET 2011 Conference, the Hong Kong/UBC Summer Microeconomics 2011 Conference, and the Harvard/MIT theory seminar, for questions and comments.
Forecasting Construction Tender Price Index in Ghana using Autoregressive Integrated Moving Average with Exogenous Variables Model

Prices of construction resources keep on fluctuating due to unstable economic situations that have been experienced over the years. Clients knowledge of their financial commitments toward their intended project remains the basis for their final decision. The use of construction tender price index provides a realistic estimate at the early stage of the project. Tender price index (TPI) is influenced by various economic factors, hence there are several statistical techniques that have been employed in forecasting. Some of these include regression, time series, vector error correction among others. However, in recent times the integrated modelling approach is gaining popularity due to its ability to give powerful predictive accuracy. Thus, in line with this assumption, the aim of this study is to apply autoregressive integrated moving average with exogenous variables (ARIMAX) in modelling TPI. The results showed that ARIMAX model has a better predictive ability than the use of the single approach. The study further confirms the earlier position of previous research of the need to use the integrated model technique in forecasting TPI. This model will assist practitioners to forecast the future values of tender price index. Although the study focuses on the Ghanaian economy, the findings can be broadly applicable to other developing countries which share similar economic characteristics.
Evaluation of Antimicrobial Properties, Phytochemical Contents and Antioxidant Capacities of Leaf Extracts of Punica granatum L.

The numerous side effects associated with the use of allopathic drugs have led to renewed level of interest in Ayurvedic medicines. Punica granatum L. is a fruit-bearing deciduous shrub, belonging to the family Lythraceae and is cultivated throughout Asia, Middle-East and the Mediterranean region. The shrub has been known to possess several medicinal and curative properties. The present investigation focuses on antimicrobial properties, phytochemical analysis and antioxidant potential of leaf extracts of Punica granatum L. The methanolic extract inhibited Staphylococcus aureus, Bacillus cereus, Salmonella typhi and Proteus mirabilis, whereas, the chloroform, ethyl acetate and aqueous extracts exhibited moderate inhibitory effects against the test bacteria. On the other hand, only methanolic extract demonstrated antifungal activity against Aspergillus niger, Aspergillus flavus, Trichophyton rubrum, Candida albicans and Cryptococcus sp . The phytochemical screening of the methanolic extract of the leaves revealed the presence of carbohydrates, reducing sugars, sterols, glycosides, phenolics, tannins, flavonoids, proteins and saponins, whereas, gums were not detected. Total antioxidant potential of the methanolic and aqueous extracts were found as 2.26 and 1.06 mg of ascorbic acid equivalent per ml of the extract, respectively. The results indicated that the methanolic extract of the leaves are pharmacologically more active than the other extracts.
Molecular characterization and growth optimization of halo-tolerant amylase producing bacteria isolated from salt mines of Karak, Pakistan

Microorganisms are commonly used for the production of different types of enzymes, among which amylases are extensively used for different industrial purposes like food industry, paper industry, textile industry and detergents etc. In this study, extremophilic bacteria were isolated from salt mines of Karak, Pakistan which have the ability to grow and express amylases at diverse environmental conditions. In Total, 43 out of the 53 bacteria were found positive for amylase production. Furthermore, microscopic, biochemical and phylogenetic analysis inferred from 16S rRNA gene sequencing identified that amylase producing strain SBA-5 belong to Bacillus subtilis. The strain SBA-5 identified as Bacillus subtilis exhibited high amylaseproduction at pH 9 and temperature 37°C. The present study revealed that the salt mines of Karak have high population of halotolerant microorganism feasible for use under diverse environmental conditions, which can be of great importance for various bio-industrial applications. Keywords: Amylase producing bacteria; Protein purification; Salt mines of Karak http://dx.doi. org/10.19045/bspab.2017. 60038
How to sit on Two Sides of the Table? Swedish and Norwegian Unions’ Approaches to Representative Worker Participation during the 20th Century

To this day, participation rights in Sweden have been reserved for union members both on the company level and on the board level, while all employees in companies, which are covered by respective agreements and laws, have voting rights in Norway. The aim of this article is twofold: First of all, it traces this difference back in time, using historical evidence from relevant periods of the 20th century to illuminate how approaches of Swedish and Norwegian unions to representative worker participation evolved. Through the method of comparison, not only similarities and differences between the two countries but also continuities within the two union movements become apparent. It becomes clear that unions of both countries were worried about “double loyalties”, but participation was more closely and deliberately linked with membership in Sweden. This in turn points to the second aim of the article, namely to identify possible reasons for this particular difference. Why were Swedish unions apparently more worried about “free riders”? While a final explanation will not be attempted here, one possible explaining factor is that private capital concentration was higher in Sweden and that Swedish employer organizations were more powerful. Swedish unions thus might have used membership requirements with regard to participation to avoid internal splits and to protect their comparatively high unity and density. This might have helped them to confront their, in comparison with Norway, better organized adversaries. The main aim of the article, however, is the first one, namely to give a synthetical, comparative account of Swedish and Norwegian unions’ approaches to representative worker participation during the 20th century, with a main focus on voting rights.
Intrinsic torsion in quaternionic contact geometry

We investigate quaternionic contact (qc) manifolds from the point of view of intrinsic torsion. We argue that the natural structure group for this geometry is a non-compact Lie group K containing Sp(n)H^*, and show that any qc structure gives rise to a canonical K-structure with constant intrinsic torsion, except in seven dimensions, when this condition is equivalent to integrability in the sense of Duchemin. We prove that the choice of a reduction to Sp(n)H^* (or equivalently, a complement of the qc distribution) yields a unique K-connection satisfying natural conditions on torsion and curvature. We show that the choice of a compatible metric on the qc distribution determines a canonical reduction to Sp(n)Sp(1) and a canonical Sp(n)Sp(1)-connection whose curvature is almost entirely determined by its torsion. We show that its Ricci tensor, as well as the Ricci tensor of the Biquard connection, has an interpretation in terms of intrinsic torsion.
Gender Differences in the Use of Apology Speech Act in Persian

The present study investigates gender differences in the use of apologies and examines the effect of social status and social distance of on the frequency of performing and receiving apologies among males and females, in a corpus of 500 apology exchanges collected through an ethnographic method of observation in Iran and coded according to Olshtain and Cohen's (1983) model. The results revealed that there were no significant gender differences in the use of apologies in Persian, and that only gender of apologizer affected the use of explanation and promise of forbearance significantly in the corpus. It was also found that males apologized to male strangers with the highest frequency while females exchanged most apologies with their female friends, and that both men and women apologized more to equals. Significant age differences were also observed in the corpus.
Faecal carriage of extended-spectrum beta-lactamase (ESBL)-producing commensal Klebsiella pneumoniae and Escherichia coli from hospital out-patients in Southern Nigeria

Normal intestinal microflora is the major source from which common hospital- and community-acquired infections originate. This study aimed to determine faecal carriage of extended-spectrum beta-lactam (ESBL) resistant genes from commensals of out-patients in Nigeria. Non-duplicateKlebsiella pneumoniae and Escherichia coli from different hospitals were investigated for susceptibility to a panel of antibiotics, carriage of plasmid mediated β-lactam resistance, andanalysis of plasmids present, including replicon typing. The minimum inhibitory concentrations (MICs) for β-lactam antibiotics showed MIC90 of ≥256 µg/ml for all antibiotics. CTX-M carriage was 36.8% for the 114 strains; 30 of these were CTX-M-15 and 12 carried CTX-M-2. TEM-1genes were present in 102 isolates (89.5%), SHV-1 genes in 24 (21.1%), OXA-1 in 36 (31.6%) and 10 (8.8%) in AmpC genes detected. There was no significant difference in the proportion of ESBL genes detected in E. coli and K. pneumoniae (t test; p = 0.64; p > 0.05) and between hospitals (c2 = 0.35; p = 0.84; p > 0.05). IncF was the common plasmid encoding β-lactamases. High faecal carriage of ESBL genes in commensals, importantly classical CTX-M-15 in out-patients is a reflection of the prevalence from clinical specimens in diseased conditions in Nigeria. Key words: Faeces, bacteria, plasmid, extended-spectrum beta-lactam (ESBL) genes, Nigeria.
Screening of antibacterial activity of some underutilized fruits of Sapotaceae

Screening of underutilized fruits of Sapotaceae family Manilkara hexandra and Mimusops elengi were examined for antibacterial activity at their successive stages of growth and ripening. Zone of inhibition and minimum inhibitory concentration (MIC) were determined against medically important bacterial strains namely Bacillus cereus, Bacillus subtilis, Micrococcus luteus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Salmonella paratyphi and Salmonella typhi. The infusion extracts were used and the zone of inhibition was determined by agar well diffusion method. The methanol extracts of both the fruits screened for the present study proved to be more potent than the other extracts used. The pre-ripened and ripened stages of both the fruits exhibited moderate to high activity against most of the tested organisms. Higher activity was recorded using the fruit extracts of Manilkara hexandra while Mimusops elengi exhibited less activity against most of the tested bacterial strains. MIC value of 1 mg/ml was found effective while using methanol extract of ripened fruit of Mimusops elengi against Salmonella typhi and methanol extract of ripened fruit of Manilkara hexandra at 2 mg/ml inhibited Salmonella paratyphi and Salmonella typhi. Hence, the present study concludes that the underutilized fruits of Manilkara hexandra and Mimusops elengi can be further studied to discover the bioactive natural compounds that may serve and facilitate pharmacological studies leading to synthesis of a more potent drug with reduced toxicity.
Prevalence of Smear Positive Pulmonary Tuberculosis among Diabetic Patients in Southwest of Iran

Background and purpose: Several investigations recognized diabetes mellitus as one of the main risk factors for pulmonary tuberculosis (TB). This study aimed at determining the prevalence of smear-positive pulmonary TB in diabetic patients in Southwest of Iran. Materials and methods: A census study was conducted from April 2010 to December 2011 in diabetic clinic in Zahedan. Standard chest radiography and sputum smear examination were performed on diabetics with tuberculosis symptoms. Cases of active TB were identified and referred to the directly observed treatment, short-course (DOTS) centers. In addition, a purified protein derivative (PPD) skin test was done for all patients. Those with a positive PPD were referred to TB centers, based on their clinical signs and chest X-Ray results. Results: Among 400 diabetics, 269 (67.25%) patients had up to 4 clinical signs of TB, and laboratory paraclinical examinations revealed 4 cases of smear-positive pulmonary TB. The results of PPD test was negative for 64.2% (<5mm) while it was borderline for 29.5% (5 to 9mm) and positive for 6.35% (10 to 14mm). Conclusion: The results of this study indicate high prevalence of smear-positive TB in diabetic patients compared with expected cases in the community and global population. Thus, TB screening in patients with diabetes is recommended in order to control and succed in treatment of the two diseases.
A LYAPUNOV CHARACTERIZATION OF ASYMPTOTIC CONTROLLABILITY FOR NONLINEAR SWITCHED SYSTEMS

Abstract. In this paper, we show that general nonlinear switched sys-tems are asymptotically controllable if and only if there exist control-Lyapunov functions for their relaxation systems. If the switching signalis dependent on the time, then the control-Lyapunov functions are con-tinuous. And if the switching signal is dependent on the state, then thecontrol-Lyapunov functions are C 1 -smooth. We obtain the results fromthe viewpoint of control system theory. Our approach is based on therelaxation theorems of diﬀerential inclusions and the classic Lyapunovcharacterization. 1. IntroductionThe problem of Lyapunov characterizations of asymptotic behavior is ofparticular interest in the design and analysis of robust feedback controls. It canbe traced back to the pioneering work of Lyapunov[9], and has been extensivelystudied since 1950s’. As for the literature on asymptotic stability analysis ofswitched systems, despite the fact that it is vast and growing, the Lyapunovcharacterization method with the relaxation theorems of diﬀerential inclusionsis still one of the very few starting points for nonlinear switched systems.By a nonlinear switched system, we mean a hybrid dynamical system that iscomposed of a family of continuous-time subsystems and a rule orchestratingthe switching signal between the subsystems (see [2]). The controllability ofnonlinear switched systems has been discussed for a long time. A populartechnique for this research relies on Lie algebraic methods (see [1, 7, 10]). Inthis paper, we consider the asymptotic controllability of nonlinear switchedsystems by using the Lyapunov characterization with the relaxation theorems
Learner perceptions of a concordancing tool for academic writing

Online templates have the potential to scaffold complex writing processes and to provide information and language prompts for writers. The purpose of this study is threefold. First, for assisting students in their scholarly writing, an online Scholarly Writing Template (SWT) was designed and developed. SWT includes two major features: (1) an information template that guides students in their development of content, and (2) a language template that provides students with language support by using a discipline-specific corpus and concordancer as a source of language examples. The second purpose of this study rests on efforts to examine the effects that the learner variables had on participants' perception of the SWT. To this end, the author implemented the SWT into an academic-writing course and surveyed 20 participants regarding their perceptions of the SWT. Third, individual retrospective interviews were conducted to understand the learning processes, the strategies in use, and the perceptions of students in relation to the students' different proficiency and publication experiences. The results of the study show that students held a positive attitude towards the scholarly writing template and that the template had varying effects on students' scholarly writing processes and on students' use of strategy. Implications and recommendations for future research and system design are addressed.
Active Transient Acousto-Structural Response Control of a Smart Cavity-Coupled Circular Plate System

The transient vibroacoustic response suppression of a piezo-coupled sandwich circular plate backed by a rigid-walled cylindrical acoustic enclosure is investigated. Problem formulation is based on the linear acoustic wave theory, Kirchhoff thin plate model, fluid/structure compatibility relations, Rayleigh integral formula, and active damping control (ADC) strategy. Matlab’s Genetic Algorithm (GA) is utilized to identify and optimize the feedback controller gain parameter based on a multi-objective performance index function. Durbin’s numerical Laplace inversion scheme is then used to calculate the key acousto-structural response parameters due to a transverse impulsive shock force for selected cavity depths. Numerical simulations demonstrate satisfactory performance of adopted control methodology in effective suppression of panel displacement response and radiated external sound pressure for enclosures of shallow and moderate depths. Limiting cases are considered and accuracy of the proposed model is rigorously verified.
Variations in time and space of trace metal aerosol concentrations in urban areas and their surroundings

Abstract. Using an unprecedentedly large geochemical database, we compare temporal and spatial variations in inhalable trace metal background concentrations in a major city (Barcelona, Spain) and at a nearby mountainous site (Montseny) affected by the urban plume. Both sites are contaminated by technogenic metals, with V, Pb, Cu, Zn, Mn, Sn, Bi, Sb and Cd all showing upper continental crust (UCC) normalised values >1 in broadly increasing order. The highest metal concentrations usually occur during winter at Barcelona and summer in Montseny. This seasonal difference was especially marked at the remote mountain site in several elements such as Ti and Rare Earth Elements, which recorded campaign maxima, exceeding PM10 concentrations seen in Barcelona. The most common metals were Zn, Ti, Cu, Mn, Pb and V. Both V and Ni show highest concentrations in summer, and preferentially fractionate into the finest PM sizes (PM1/PM10 > 0.5) especially in Barcelona, this being attributed to regionally dispersed contamination from fuel oil combustion point sources. Within the city, hourly metal concentrations are controlled either by traffic (rush hour double peak for Cu, Sb, Sn, Ba) or industrial plumes (morning peak of Ni, Mn, Cr generated outside the city overnight), whereas at Montseny metal concentrations rise during the morning to a single, prolonged afternoon peak as contaminated air transported by the sea breeze moves into the mountains. Our exceptional database, which includes hourly measurements of chemical concentrations, demonstrates in more detail than previous studies the spatial and temporal variability of urban pollution by trace metals in a given city. Technogenic metalliferous aerosols are commonly fine in size and therefore potentially bioavailable, emphasising the case for basing urban background PM characterisation not only on physical parameters such as mass but also on sample chemistry and with special emphasis on trace metal content.
Educational Computer Games and Spanish Content Learning

The purpose of this mixed-methods study was to determine differences in engagement, satisfaction, and Spanish language content learning among participants playing one of two dif- ferent educational computer games. Additionally, this study served as preliminary research for future research projects to detect and correct problems at the pilot stage. Participants were briefly introduced to the Spanish content material prior to using the computer games and completed pre- tests, post-tests, and satisfaction/engagement surveys as a way to obtain learning results. The small sample size acquired for the study did not yield any statistically significant difference, but the research did permit examination of the procedures used and a report of results in a more descrip- tive manner. The findings led to possible ideas for future research and the necessity to revise the pre- and post-tests.