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Presidential speeches are among the best ways to demonstrate heads of state's competence in dealing publically with domestic as well as foreign issues, and thus contribute to their political survival. This study uses a new one-million-word parallel corpus of Arabic and English to investigate the political topics that King Abdullah II of Jordan discusses when using the Arabic language to address Jordanian or Arab audiences and when using the English language to address Western/international audiences. The corpus covers the period from 1999 to 2015. Using Wordsmith 7 and examining the most frequent 25 Arabic and English words, we found that King Abdullah tends to discuss particular issues on all occasions, locally, nationally, and globally. These include Arab and regional matters as well as the peace process in the Middle East. It is also found that local themes that are mainly associated with Jordan, its political system, and economic and social challenges were more frequent in the Arabic corpus when compared to its English counterpart. However, Jordan's involvement in some issues in the Middle East, especially in Palestine and Iraq, was more important in the English texts. The study concludes that parallel corpora can be a rich resource for discourse studies. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the in-plane and out-of-plane free vibrations analysis of both solid and annular sector plates with time-dependent properties. The Fourier expansion and the perturbation technique are employed to solve the partial differential equations based on the first-order shear deformation theory. By defining a new parameter, the motion equations which have variable coefficients convert to equations with constant coefficients that lead to a closed-form solution for each order of the perturbation expansion. Due to the use of this displacement field, rapid convergence and high accuracy results can be easily obtained for both in-plane and out-of-plane natural frequencies. The influences of some key parameters including the inner to outer radius ratios, sector angle, thickness to radius ratios, and damping parameters on free vibration of the viscoelastic sector plates are illustrated and analyzed, which may serve as benchmark solutions in the future. Besides, the results are compared with the actual results from the literature, classic theory of plates, and finite element analysis. The present formulation yields many new and accurate results at a low computational cost for the study of mechanical and geometrical parameters. [ABSTRACT FROM AUTHOR]

This study examines all of the equations necessary to derive the parameters for seven probability distributions of three parameters typically used in flood frequency research, namely the Pearson III (PE3), the generalized extreme value (GEV), the Weibull (W3), the log-normal (LN3), the generalized Pareto Type II (PG), the Rayleigh (RY) and the log-logistic (LL3) distributions, using the higher-order linear moments method (LH-moments). The analysis represents the expansion of previous research whose results were presented in previous materials, and is part of hydrological research aimed at developing a standard for calculating maximum flows based on L-moments and LH-moments. The given methods for calculating the parameters of the examined distributions are used to calculate the maximum flows on Romania's Prigor River. For both methods, the criterion for selecting the most suitable distribution is represented by the diagram of the L-skewness–L-kurtosis and LH-skewness–LH-kurtosis. The results for Prigor River show that the PG distribution is the best model for the L-moments method, the theoretical values of the statistical indicators being 0.399 and 0.221. The RY distribution is the best model for the LH-moments technique, with values of 0.398 and 0.192 for the two statistical indicators. [ABSTRACT FROM AUTHOR]

AbstractHydraulic modelling of floods plays an important role in flood management and the related risk reduction. The case study in this research was a 20-km reach of the Atrak River in the upstream of Maraveh Tappeh City, which is one of the most hazardous regions of Iran from flood viewpoint. The aim of this research was to estimate the accuracy of the TanDEM-X digital elevation model with a resolution of 12 meters in simulating flood hydraulic characteristics. To achieve this aim, the HEC-RAS 2D model was used in steady conditions to simulate floods with a return period of 5, 10, 25, 50, 100, and 200 years. The results indicated that the inundation area varied in the range of 4.40 km2(return period of 5 years) and5.93 km2 (return period of 200 years). In the return period of 200 years, the mean flow depth and velocity increased by 67.9 and 49.5% compared to the return period of 5 years, respectively. The sensitivity test also indicated that the maximum sensitivities of the inundation area, mean flow depth, and mean flow velocity to Manning’s coefficient were4.65, 4.84, and -12.23%, respectively. The validation results of the HEC-RAS 2D model by using the inundation area extracted from Landsat-8 OLI satellite images for a return period of 10 years showed that the fit percentage indicator was 86%. The results of this study indicated an initial effort for hydraulic modelling of flood characteristics with the TDX elevation digital model.Keywords:HEC-RAS 2D model, Frequency analysis, Hydraulic modelling, Landsat-8 satellite images IntroductionFloods are among the most common and destructive natural disasters worldwide, imposing various adverse effects in different countries (Bui et al., 2018). These include fatalities, damage to infrastructures, people displacement, and environmental damages (Rahmati et al., 2020). Over the last decade, floods have affected millions of people worldwide and caused a damage of more than US$ 400 billion (Aerts, 2020). In Asia, more than 90% of human casualties resulting from natural disasters stem from flood events (Smith, 2003). Among several countries in Asia, Iran faces destructive floods each year due to its vast extent and heavy precipitations in most basins (Jahangir et al., 2019). Over the past 60 years, more than 3,700 flood events have been reported in Iran, while during the last decade, the damage caused by flooding has increased by 250% (Norouzi and Taslimi, 2012). Iran has recently experienced immense floods because of poor watershed management and climate change (Pouyan et al., 2021). In 2019, flooding events affected 25 out of 31 provinces, resulting in more than 77 human casualties and damage of US$ 2.2 billion (Khosravi et al., 2018). Even though we do not have an accurate answer to how climate change may impact flooding events, such as the ones that occurred in 2019(Sherpa and Shirzaei, 2021), a recent study has suggested that Iran will probably experience a higher frequency of floods in the future (Vaghefi et al., 2019). In addition, the growth of urbanization and increasing deforestation will make the condition worse (Arabameri et al., 2019). MethodologyIn the current study, the long-term (1977-2017) data of maximum discharge in the hydrometric station of Qazanqaya were used for the frequency analysis of Flood Peak Discharge (FPD). The stationarity in the time series of annual maximum peak discharge was checked before fitting the distribution. For computing FPD in the various return periods for the hydrometric station of Qazanqaya, the annual maximum discharge records were fitted via EasyFit software. Three goodness-of-fit criteria, including Anderson-Darling, Kolmogorov-Smirnov, and Chi-square, were adopted to select the best-fitted distribution. Finally, flood discharges with 5-, 10-, 25-, 50- 100-, and 200-yr return periods were estimated for the hydrometric station based on the corresponding best-fitted distribution. This study simulated 2D steady flow in a return period of 5-200 years using HEC-RAS 5.0 software (U.S. Army Corps of Engineering, 2016). Due to the complex numerical schemes, 2D diffusive wave equations could provide greater stability and faster calculation times (Li et al., 2020) and were thus used in this study to simulate 2D steady flows in a return period of 5 to 200 years. The peak flow discharges in the return periods of 5-200 years estimated from frequency analysis in the hydrometric station of Qazanqaya were considered as the upstream boundary conditions in the hydraulic model. Furthermore, the downstream boundary conditions were considered as normal depth conditions obtained based on the energy slope. Manning’s roughness coefficients of the main channel and floodplain were estimated based on the land cover mapand USGS method (Arcement and Schneider, 1989). In the previous studies, modification of Normalized Difference Water Index (NDWI) has been successfully done to map the flooding areas (Li et al., 2018). Hence, based on the date of the flood events, which were recorded in the hydrometric station of Qazanqaya, the flooded area was extracted from Landsat-8 OLI images. On the other hand, the fit percentage indicator proved to be useful for the validation of flood inundation models (Khojeh et al., 2022). A value of closer to 100% could denote a better agreement in flood extent modeling by TDX Digital Elevation Model. DiscussionThe results of hydraulic modelling indicated that the inundation area varied in the range of 4.40 square kilometers (return period of 5 years) and5.93 square kilometers (return period of 200 years). On the other hand, in the return period of 200 years, the mean flow depth and velocity increased by 67.9 and 49.5% compared to the return period of 5 years, respectively. The validation results of the HEC-RAS 2D model by using the inundation area extracted from Landsat-8 OLI satellite images for a 10-yr return period indicated that the fit percentage indicator was 86%, indicating a high agreement of flood modeling results based onthe TDX digital elevation model. ConclusionThe results of the frequency analysis and estimation of flood peak discharges with a return period of 5 to 200 years in the Atrak River Basin showed that this basin with peak discharges between 487.8 m3/s (5-year flood) and 1605.6 m3/s (200-year flood) could be considered as one of the most dangerous basins in Iran, which could cause a lot of human and financial losses, especially for floods with a high return period. Although HEC-RAS 2D modeling based on the TDX digital elevation model with a resolution of 12 m indicated that this digital elevation model with an accuracy of 86% (14% error) was probably better than digital elevation models, such as SRTM, ASTER, and ALOS, with a resolution of 30 m , its validation for other flood-prone areas of Iran was necessary. References- Aerts, J. C. J. H. (2020). Integrating agent-based approaches with flood risk models: A review and perspective. 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The influence of digital elevation model resolution on overland flow networks for modeling urban pluvial flooding. Water Science and Technology, 60(12), 3137-3149.- Li, J., Yang, X., Maffei, C., Tooth, S., & Yao, G. (2018). Applying independent component analysis on Sentinel-2 imagery to characterize geomorphological responses to an extreme flood event near the non-vegetated Río Colorado terminus, Salar de Uyuni, Bolivia. Remote Sensing, 10(5), 725.- Li, J., Zhao, Y., Bates, P., Neal, J., Tooth, S., Hawker, L., & Maffei, C. (2020). Digital Elevation Models for topographic characterization and flood flow modeling along low-gradient, terminal dryland rivers: A comparison of spaceborne datasets for the Río Colorado, Bolivia. Journal of Hydrology, 591, 125617.- Modarres, R., Sarhadi, A., & Burn, D. H. (2016). Changes of extreme drought and flood events in Iran. Global and Planetary Change, 144, 67-81.- Muench, R., Cherrington, E., Griffin, R., & Mamane, B. (2022). 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Abstract The probability of a train running over a bridge when an earthquake occurs is increasing with the total mileage of China’s high-speed railway network expanding. To study this issue, a three-dimensional train-track-bridge dynamic interaction system subjected to seismic excitations is established based on commercial mathematical software. Besides, a set of motion equations of the system are derived according to the multibody dynamics, the finite element method theory and the bridge seismic theory. Moreover, in order to study the dynamic response of high-speed railway bridges under earthquake, a series of experiments are conducted on a scaled high-speed railway simple supported bridge model with a ballastless track slab excited by shaking table tests. Meanwhile, the strain of rails, track slabs, base plates and girder in various working conditions are measured by quasi-distributed optical fiber sensing stuck in bridge members. At last, the dynamic response of each structure member is demonstrated in the time and frequency domains. Furthermore, the seismic isolation performance of bridge members, such as fasteners, cement asphalt (CA) mortar layer and so on, is explained in details.

Frequency analysis of daily rainfall or return period of rainfall and flooding events is very important considering the behavioral complexity in water resources management; because ignoring it can lead to urban destructive floods. In the present research, three distribution functions of Pearson, Beta, and Gamma were compared to investigate and select the most appropriate distribution function for the precipitation data acquired from meteorology stations and CHIRPS satellite in seven stations in the watershed of Bustan Dam. Statistical analyses showed that satellite data were ineffective to estimate daily precipitation due to high errors in RMSE, MAD, and NASH. Meteorological data were used to spot the best distribution. Google Earth Engine and Python programming language were used. Then, the selected distribution function was used to determine the maximum daily rainfall, frequency probability, and return period of 2, 10, 50, 100, and 200 years. The results of the goodness of fit test, Error Sum of Squares, Bayesian Information Criterion, Akaike Information Criteria well as Kullback-Leibler Divergence showed that in five stations of Kalaleh, Qarnaq, Golestan National Park, Golestan Dam, and Glidagh, the Pearson function is the most suitable distribution function. Also, in the other two stations (Gonbad and Tamar), the Beta function was recognized as a suitable function. However, Gamma distribution in the study area is not efficient. So, it can be concluded that heavy and irregular rainfall can be effective in choosing the best distribution function at each station. Therefore, it is recommended to consider the maximum possible rainfall and as a result of the possible occurrence of floods with principled and accurate management to prevent human and financial losses in susceptible areas, especially in the study area.

Sıklık, metinlerin ölçülebilir özelliklerindendir. Sıklık analiziyle elde edilen veriler ilk okuma-yazma ve Türkçe dil bilgisi öğretimi, Türkçe ders kitaplarının yazımı ve değerlendirilmesi, müfredatının oluşturulması ve yenilenmesi gibi birçok konuda önemli bilgiler içerebilir. Bu çalışmada ilkokul 1, 2, 3 ve 4. sınıf Türkçe ders kitaplarında bulunan bütün okuma metinlerinin kelime, harf ve hece sıklıkları saptanmış, sonuçlar sınıf ve yayınevlerine göre kategorik olarak sunulmuştur. 1. sınıf metinleri daha az sayıda kelimeden oluşmuştur. Sınıf seviyesi arttıkça ve ilk okuma metninden son okuma metnine doğru ilerledikçe kelime sayısı da artmıştır. Kelimelerin ağırlıklı olarak 5 harfli ve 2-3 heceli olduğu, ünlü ve ünsüz uyumuna uydukları belirlenmiştir. Farklılıklar olsa da sınıf seviyeleri ve yayınevlerine göre en çok ve en az kullanılan harflerin yakın oranda seyrettiği saptanmıştır. Hecelerin en çok CV tipinde bulunduğu, ortalama hece sayısının sınıf seviyesi ve yayınevine göre benzerlik gösterdiği, bu değerin ilk okuma metinlerinde düşükken son metinlere doğru yükseldiği tespit edilmiştir. Seslerin öğretim sırasıyla harflerin kullanım sıklıklarının örtüşmediği fakat 2019 Türkçe Dersi Öğretim Programı’nın 1. grubunda yer alan harflerin sıklık oranının %47’ye ulaştığı görülmüştür. Çalışma kapsamında analiz edilenler itibariyle aynı sınıf seviyesindeki farklı yayınevlerinde birbirine yakın sonuçların alınması olağan bir durumken farklı sınıf seviyelerinde de birçok benzerlik görülmesi, sonuçların aynı veya çok yakın olması dikkat çekici ve vurgulanması gereken bir nokta olarak ortaya çıkmıştır.

This paper describes the frequency analysis of absolute maximum air temperatures, using annual maximum series (AMS) in the period 1961–2010 from 40 climatological stations in Serbia with maximum likelihood estimation of distribution parameters. For the goodness of fit testing of General Extreme Value (GEV), Normal, Log-Normal, Pearson 3 (three parameters), and Log-Pearson 3 distribution, three different tests were used (Kolmogorov-Smirnov, Anderson-Darling, chi-square). Based on the results of these tests (best average rank of certain distribution), the appropriate distribution is selected. GEV distribution proved to be the most appropriate one in most cases. The probability of exceedance of absolute maximum air temperatures on 1%, 0.5%, 0.2%, and 0.1% levels are calculated. A spatial analysis of the observed and modeled values of absolute maximum air temperatures in Serbia is given. The absolute maximum air temperature of 44.9 °C was recorded at Smederevska Palanka station, and the lowest value of maximum air temperature 35.8 °C was recorded at Zlatibor station, one of the stations with the highest altitude. The modeled absolute maximum air temperatures are the highest at Zaječar station with 44.5 °C, 45.6 °C, 47.0 °C, and 48.0 °C and the lowest values are calculated for Sjenica station with 35.5 °C, 35.8 °C, 36.1 °C, and 36.2 °C for the return periods of 100, 200, 500, and 1000 years, respectively. Our findings indicate the possible occurrence of much higher absolute maximum air temperatures in the future than the ones recorded on almost all of the analyzed stations.

Estimating the storm surge magnitude and annual exceedance probability is a key element in the siting and design of coastal nuclear power plants in both the U.S. and France. However, differences in storm climatology, specifically the relative importance of tropical cyclones (TCs) versus extratropical storms (XTCs), have driven differences in estimation method development. This work compares purely statistical modeling with combined statistical and numerical simulation modeling approaches for extreme storm surge applied to the U.S. North Atlantic coast which is subject to both tropical and extratropical storms. Two frequency analysis methods are applied to observed water levels and compared to a copula-based joint probability analysis of TCs and automated frequency analysis of XTCs that is enriched with numerically simulated storms. One frequency analysis method is applied using (1) hourly at-site data and (2) hourly at-site data enriched with additional data from a homogeneous region. The other frequency analysis method is applied using (1) hourly at-site data and (2) hourly at-site data enriched with monthly water level maxima. Variables of interest used in the comparison are skew storm surge, maximum instantaneous storm surge, non-tidal residual and maximum seal level. The performance of the methods (mean surge and water level estimates and confidence intervals) depend on the variable of interest and, to some extent, on return period. Inclusion of additional information (e.g., regional water levels, and monthly maxima) in the frequency analysis methods does not have a large impact on estimated mean surge and water levels, but significantly reduces resulting confidence intervals (over 40% reduction in some cases). However, the confidence intervals still grow with increasing return period. Inclusion of simulated storms in the joint probability analysis results in significantly different mean surge and water level estimates (up to 25% higher than the frequency analysis in some cases). The joint probability analysis confidence intervals are wider than those for the frequency analysis methods lower return periods (e.g., 60%–80% wider at 100 years), but they grow much more slowly and are significantly narrower for higher return periods (e.g., 40%–60% narrower at 1 000 years). Although there are appreciable differences between the results documented in this paper, these are reasonable due to differences in the data and methods used in this comparison.

The concept of stop words introduced by H. P. Lun in the mid-20th century plays a huge role in today’s NLP practice. Stop words are used to reduce noisy text data, remove uninformative words, speed up text processing, and minimize the amount of memory required to store data.The Kyrgyz language is an agglutinative Turkic language for which no scientific study of stop words has been previously published in English. In our study, we combined frequency analysis with rule-based linguistic analysis. First, we found the most frequently used words, set a threshold, and removed words below the threshold. This way we got a list of the most frequently used words. Then we reduced the list by excluding from the list all words that do not belong to the category of function words of the Kyrgyz language. Finally, we got a list of 50 words that can be considered stop words in the Kyrgyz language. In our analysis, we used a single corpus of sentences collected and posted as an open source project by one of the local broadcasters.

Background. Spatter formation at melt pool swellings at the keyhole rear wall is a major issue for laser deep penetration welding at speeds beyond 8 m/min. A gas nozzle directed towards the keyhole, that supplies shielding gas locally, is advantageous in reducing spatter formation due to its simple utilization. However, the relationship between local gas flow, laser spot size, and the resulting effects on spatter formation at high welding speeds up to 16 m/min are not yet fully understood. Methods. The high-alloy steel AISI 304 (1.4301/X5CrNi18-10) was welded with laser spot sizes of 300 μm and 600 μm while using a specially designed gas nozzle directed to the keyhole. Constant welding depth was ensured by Optical Coherence Tomography (OCT). Spatter formation was evaluated by precision weighing of samples. Subsequent processing of high-speed images was used to evaluate spatter quantity, size, and velocity. The keyhole oscillation was determined by Fast Fourier Transform (FFT) analysis. Tracking the formation of melt pool swellings at the keyhole rear wall provided information on the upward melt flow velocity. Results. The local gas flow enabled a significant reduction in the number of spatters and loss of mass for both laser spot sizes and indicated an effect on surface tension by shielding the processing zone from the ambient atmosphere. The laser spot size affected the upward melt flow velocity and spatter velocity. [ABSTRACT FROM AUTHOR]

DC–DC buck converters have become prominent components for energy optimization in power systems, and how to improve control performances is a challenging issue to be addressed. In this paper, we aim to investigate the harmonic problem of sliding mode (SM) controlled buck converters imposed by the often-ignored unmodeled dynamics of the Hall sensor. The unified mathematical model of the whole system is established by combining the SM controller, the buck converter, and the Hall sensor, where the signal loss in the transmission process of the whole closed-loop control system is considered. Based on the Lyapunov stability theorem, the SM controller is designed to guarantee system stability, as well as to deduce the stable working areas and the tuned controller parameters. Furthermore, we introduce the descriptive function (DF) approach to investigate the influence of the unmodeled dynamics of the Hall sensor on the system harmonics in the frequency domain, which can deduce the relationship between the amplitude-frequency characteristics of the output signal and the Hall sensor. Simulations and experiments validate this paper. [ABSTRACT FROM AUTHOR]

Summary: In natural environments, plants are exposed to rapidly changing light. Maintaining photosynthetic efficiency while avoiding photodamage requires equally rapid regulation of photoprotective mechanisms. We asked what the operation frequency range of regulation is in which plants can efficiently respond to varying light.Chlorophyll fluorescence, P700, plastocyanin, and ferredoxin responses of wild‐types Arabidopsis thaliana were measured in oscillating light of various frequencies. We also investigated the npq1 mutant lacking violaxanthin de‐epoxidase, the npq4 mutant lacking PsbS protein, and the mutants crr2‐2, and pgrl1ab impaired in different pathways of the cyclic electron transport.The fastest was the PsbS‐regulation responding to oscillation periods longer than 10 s. Processes involving violaxanthin de‐epoxidase dampened changes in chlorophyll fluorescence in oscillation periods of 2 min or longer. Knocking out the PGR5/PGRL1 pathway strongly reduced variations of all monitored parameters, probably due to congestion in the electron transport. Incapacitating the NDH‐like pathway only slightly changed the photosynthetic dynamics.Our observations are consistent with the hypothesis that nonphotochemical quenching in slow light oscillations involves violaxanthin de‐epoxidase to produce, presumably, a largely stationary level of zeaxanthin. We interpret the observed dynamics of photosystem I components as being formed in slow light oscillations partially by thylakoid remodeling that modulates the redox rates. [ABSTRACT FROM AUTHOR]

This study compared research trends in universities general English program before and after the COVID-19 pandemic. After analyzing 248 articles from KCI using frequency analysis, centrality analysis, and topic modeling, this study found consistent keywords indicating a focus on learning objectives, effectiveness analysis, satisfaction surveys, and level-based learning before and after the COVID-19 pandemic. Centrality analysis revealed keywords like "teaching, research, analysis" before COVID-19 and "satisfaction, study, level, activity, effect" after COVID-19, indicating a shift towards learner satisfaction, level-based learning, and effectiveness analysis due to the transition to online learning. Topic modeling revealed shifts in research trends: Pre-COVID-19 focused on effective teaching methods, evaluation techniques, and cultural content, while Post-COVID-19 prioritized online teaching methods, web-based platforms, and selfdirected learning. Future research should address self-directed learning, attitudes and goal setting, closing learning gaps in online/blended learning, and developing effective online assessment tools and evaluation strategies. This study provides valuable insights and directions for further research in general English programs. [ABSTRACT FROM AUTHOR]

This paper describes the frequency analysis of absolute maximum air temperatures, using annual maximum series (AMS) in the period 1961-2010 from 40 climatological stations in Serbia with maximum likelihood estimation of distribution parameters. For the goodness of fit testing of General Extreme Value (GEV), Normal, Log-Normal, Pearson 3 (three parameters), and Log-Pearson 3 distribution, three different tests were used (Kolmogorov-Smirnov, Anderson-Darling, chi-square). Based on the results of these tests (best average rank of certain distribution), the appropriate distribution is selected. GEV distribution proved to be the most appropriate one in most cases. The probability of exceedance of absolute maximum air temperatures on 1%, 0.5%, 0.2%, and 0.1% levels are calculated. A spatial analysis of the observed and modeled values of absolute maximum air temperatures in Serbia is given. The absolute maximum air temperature of 44.9 °C was recorded at Smederevska Palanka station, and the lowest value of maximum air temperature 35.8 °C was recorded at Zlatibor station, one of the stations with the highest altitude. The modeled absolute maximum air temperatures are the highest at Zaječar station with 44.5 °C, 45.6 °C, 47.0 °C, and 48.0 °C and the lowest values are calculated for Sjenica station with 35.5 °C, 35.8 °C, 36.1 °C, and 36.2 °C for the return periods of 100, 200, 500, and 1000 years, respectively. Our findings indicate the possible occurrence of much higher absolute maximum air temperatures in the future than the ones recorded on almost all of the analyzed stations. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of heatwaves in mainland Portugal from 1 October 1980 to 30 September 2021 (41 hydrological years). It addresses a research gap by providing an updated assessment using high-resolution reanalysis daily minimum and maximum temperature data (Tmin and Tmax) from the gridded ERA5-Land dataset, overcoming the lack of publicly available daily temperature records. To assess the representation of the previous dataset, nine different grid-point locations across the country were considered. By comparing monthly ERA5-Land temperature data to ground-based records from the Portuguese Met Office, a monthly validation of the data was conducted for the longest common period, demonstrating good agreement between the two datasets. The heatwave magnitude index (HWMI) was employed to establish the temperature thresholds and thus identify heatwaves (defined as three or more consecutive days above the threshold). With over 640 Tmin heatwave days recorded at each of the nine ERA5-Land grid-points, data analysis revealed a discernible upward trend in Tmin heatwaves. The grid-point situated in the capital city's urban area, i.e., Lisbon, exhibited the highest number of Tmin heatwave days. With an average of more than 800 Tmax heatwave days over the 41-year period, the northern and interior regions of Portugal had the greatest number of occurrences, reaching up to 916. A kernel rate estimation method was applied to further investigate the annual frequency of Tmin and Tmax heatwave occurrences. Results exhibited clear temperature changes, with a widespread increase in the number of heatwave days over the past two decades, particularly for Tmax. In summary, the occurrence of this phenomenon displayed significant spatial variations, with the southern interior and coastal grid-points experiencing a greater increase in annual Tmax heatwave days, rising from 10 to 30 between 2018 and 2019. [ABSTRACT FROM AUTHOR]

The ability to know the rules of word formation in a language and to use these rules in the process of understanding and producing more complex words is part of language skills. In German, it is possible to derive words of different types and with various meanings with morphemes with suffixes such as -keit, -ung, -ig, -lich. In this study, mixed research method was used in which both quantitative and qualitative data collection methods were used together. The study aimed to answer the following questions: What are the top ten most frequent words derived with the morpheme -keit in the DeReKo corpus? What are the significant conclusions from the data obtained from the frequency analysis of the DeReKo corpus? What is the importance of frequency analysis in the context of German as a Foreign Language? What is the importance of corpus-based studies in the context of German as a Foreign Language? In this study, first of all, the frequency of words derived with the statistically significant morpheme -keit was investigated through frequency analysis in the DeReKo corpus. According to the results of the frequency analysis in DeReKo, the top ten words with the highest frequency are "Möglichkeit, Möglichkeiten, Öffentlichkeit, Tätigkeit, Schwierigkeiten, Aufmerksamkeit, Wirklichkeit, Unabhängigkeit, Fähigkeiten and Notwendigkeit". Finally, the importance of corpus-based studies and frequency analysis for GFL is emphasized. [ABSTRACT FROM AUTHOR]

The defense against urban pluvial flooding relies on the prediction of rainfall frequency, intensity, and long-term trends. The influence of the choice of the complete time series or the wet-day series on the rain analyses remains unclear, which affects the adaptive strategies for the old industrial cities such as Changchun in Northeastern China, with the outdated combined sewer systems. Based on the data from the two separate weather stations, four types of distributions were compared for analyzing the complete daily precipitation series, and their fitting accuracy was found in decreasing order of Pearson III, Pareto–Burr–Feller distribution (PBF), generalized extreme value (GEV), and Weibull. The Pearson III and the PBF probability distribution functions established based on the complete time series were found to be at least 458% and 227%, respectively, more accurate in fitting with the consecutive observations than those built from the wet-day-only series, which did not take account of the probability of the dry periods between the rain events. The rain depths of the return periods determined from the wet-day-only series might be over-predicted by at least 76% if the complete daily series were regarded as being more closely representative of the real condition. A clear threshold of 137 days was found in this study to divide the persistent or autocorrelated time series from the antipersistent or independent time series based on the climacogram analysis, which provided a practical way for independence determination. Due to the significant difference in the rain analyses established from the two time series, this work argued that the complete daily series better represented the real condition and, therefore, should be used for the frequency analysis for flood planning and infrastructure designs. [ABSTRACT FROM AUTHOR]

Due to its impact on the derivation of hydrological models and the safe design of sewer and storm networks, the anticipation of rainfall events should be intensively studied. In this regard, studying the rainfall events in Karbala, Iraq, has specific importance after the rapid increase in population in this city and the impact of climate change beyond 2003. Herein, the maximum daily rainfall depth of Karbala city has been analyzed to investigate and extract its probability of future occurrence using frequency analysis. Eight theoretical probability distributions, which are Weibull, Gamma, Gumbel, Log normal, Generalized Extreme Value, Normal, Exponential, and Log-Pearson Type III, were fitted using Hyfran Plus software to simulate the characteristics of the observed probability of rainfall depth. Based on the results of four statistical indicators, the exponential distribution revealed the best performance as compared with other distributions. Accordingly, ‎the synthetic storms of 24 hr were derived‎ for cumulative and incremental distribution of rainfall depth using the Soil Conservation Service method type ΙΙ for the arid and semiarid region to recurrence periods ‎‎(T = 2, 5, 10, 15, 25, 50, 100, 200, and 500), also the rainfall intensity duration frequency curves were developed. As an essential finding, new validated empirical formula has been proposed to optimize the coefficients of the location of Karbala city which may fill the gap for predicting the rainfall intensity and improving storm management strategies in Iraq. [ABSTRACT FROM AUTHOR]

Purpose: With the rapid development of urban metro systems in the growing cities of China, a way to reduce metro train-induced track vibrations transmitted through ground to surrounding buildings has attracted the attention of engineering researchers. Using additional mass, damping and flexural stiffness to improve the dynamic performance of metro tracks, a Tuned Rail Damper (TRD) is developed to mitigate the vibrations of the metro tracks. Methods: In this paper, a laboratory hammer test is designed and carried out to assess the vibration performance of a 3-interval (of 3 × 0.6 m) metro track installed with the TRD sets. Results: The hammer test results indicated that depending on the position of a hammer impulse acting on the 3-interval track unit, different excitation frequencies would be measured. Conclusion: According to the experimental study, the TRD has advantages such as easy installation, convenient inspection by hammer test, and good vibration reduction performance for its flexural strengthening effect on metro tracks. Moreover, the composed TRD-track system has a robust ability to reduce vibrations and an increase of higher frequencies compared to conventional tracks. This dynamic feature can decrease the risk of clip failure in a fastening system subjected to intensive excitations from moving metro trains. [ABSTRACT FROM AUTHOR]

This paper presents a non-contact diagnostic technique for solid rocket motors (SRM) based on the analysis of acoustic vibrations generated by the supersonic jet of combustion products from the nozzle. The pressure in the combustion chamber of a E-5-0 model sold rocket motor was determined experimentally by a noninvasive control method using a dynamic microphone placed at a prescribed distance from the test object and recording the acoustic fields generated by the operating engine. Experiments confirmed the possibility of non-contact determination of combustion chamber pressure from the frequency of acoustic vibrations and the sound pressure generated by the jet of combustion products of the model SRM. Calculated pressures are in satisfactory agreement with the values recorded by an intra-chamber pressure transducer. [ABSTRACT FROM AUTHOR]

In this study, we developed a data-driven frequency domain analysis method for rotor systems using the NARX (Nonlinear Auto-Regressive with eXternal input) model established by system vibration signals. We propose a model-based index of fault features calculated in a multi-frequency range to facilitate condition monitoring of rotor systems. Four steps are included in the proposed method. Firstly, displacement vibration signals are collected at multiple monitored rotating speeds. Secondly, the collected signals are processed as output data and the corresponding input data is generated. Then, NARX models are developed with input and output data to characterize the rotor system. Finally, the NRSF (Nonlinear Response Spectrum Function)-based nonlinear fault index is calculated and compared to the healthy condition. An experimental application to the misaligned rotor system is also demonstrated to verify its effectiveness. Our results indicate that the value of the index directly reflects the severity of the misaligned fault. [ABSTRACT FROM AUTHOR]

Frequency analysis is a widely used method in hydrology; however, the conventional approaches to frequency analysis do not consider the spatial dependence between stations. This study proposes a novel approach for multisite frequency analysis using the copula method. This approach uses the framework of pair copula construction to extended bivariate copula functions for multivariate analysis, allowing for non-homogeneous marginal distribution and spatial dependence. Our approach was applied to analyze hourly rainfall in Taiwan's Lanyang watershed from 1996 to 2011, constructing the multisite rainfall distribution to estimate the frequency of extreme rainfall events. The results showed the nonlinear relationships and distinct frequency distributions of rainfall across the study area due to changes in elevations. Based on the copula-based multisite rainfall distribution, the study simulated extreme rainfall events at multiple sites with predetermined frequencies, preserving the spatial characteristics of rainfall more accurately than previous methods. This approach avoids potential underestimation and overestimation of hourly rainfall intensity at specified return periods resulting from assumptions of homogeneity and spatial independence. This study also evaluated possible multisite rainfall combinations at a given frequency using Monte-Carlo simulation. These simulations characterized spatial uncertainties in design multisite rainfall, providing critical information for water resources management and hydrological design. [ABSTRACT FROM AUTHOR]

The basic parameters of an electromagnetic levitation systems are resistance of the coil, inductance of the coil, air-gap between magnet and the object, coil current, mass of the object, controller parameters and so on. The levitation systems are highly unstable and strongly non-linear. In real-life applications, these parameters are supposed to vary. A proportional–integral controller for the inner current control loop and a lead compensator for the position control loop have been designed and tested. The performance study under various parametric effects has been investigated broadly. Finally, both the stability for the proposed levitation system has been achieved with a better operating zone using linear state variable feedback controllers. The system dynamic performances have been recorded for variations of physical system parameters. The sensitivity/robustness of the set-up has been studied. This study will give an insight for designing any corrective measures and an overall idea to develop a levitation system. [ABSTRACT FROM AUTHOR]

The bank vault's security system require a reliable and highly secure authentication system. Providing a biometric-based authentication for safety vaults eliminates the possibility for a robber to forcefully demand access to the vault. Brainwaves are one of the most reliable biometrics of a person since it is unique and inherent to a person. This work develops and evaluates a biometric-based user authentication system for a bank vault that would extract the brainwaves using an electroencephalogram device of a user. The system was evaluated using cognitive tasks such as selective attention, reaction to stimuli, long-term memory, sustained attention and divided attention using frequency domain analysis. In addition, the duration of the authentication process and user acceptability were also evaluated. Results show through the cognitive task analysis that the vault is able to remain locked for almost 98% of the time. Finally, the accuracy of the system is 90.08% when the task for long-term memory is applied in best-case scenario. [ABSTRACT FROM AUTHOR]

A direct way to estimate the likelihood and magnitude of extreme events is frequency analysis. This analysis is based on historical data and assumptions of stationarity, and is carried out with the help of probability distributions and different methods of estimating their parameters. Thus, this article presents all the relations necessary to estimate the parameters with the LH-moments method for the family of distributions defined only by the quantile function, namely, the Wakeby distribution of 4 and 5 parameters, the Lambda distribution of 4 and 5 parameters, and the Davis distribution. The LH-moments method is a method commonly used in flood frequency analysis, and it uses the annual series of maximum flows. The frequency characteristics of the two analyzed methods, which are both involved in expressing the distributions used in the first two linear moments, as well as in determining the confidence interval, are presented. The performances of the analyzed distributions and the two presented methods are verified in the following maximum flows, with the Bahna river used as a case study. The results are presented in comparison with the L-moments method. Following the results obtained, the Wakeby and Lambda distributions have the best performances, and the LH-skewness and LH-kurtosis statistical indicators best model the indicators' values of the sample (0.5769, 0.3781, 0.548 and 0.3451). Similar to the L-moments method, this represents the main selection criterion of the best fit distribution. [ABSTRACT FROM AUTHOR]

The frequency‐domain approach to fatigue life estimation in random loading has been largely investigated due to its computational advantages, and several methods for the frequency translation of the most common time‐domain methods have been proposed. Between the most known frequency methods, there are Bendat's method, valid for narrow‐band signals, and Dirlik's formula, which ifis considered the best result for wide‐band signals. However, a great part of the frequency methods takes the rainflow count as a reference time‐domain method and uses the rainflow damage computation as the exact value to emulate. Therefore, very few experimental data for the fatigue life of mechanical components subject to random loads are available in the literature. This work presents the setup for a series of experimental tests for specimens subjected to random loads, aiming at achieving experimental data to compare with the results provided by frequency methods. After a brief description of the materials used for the setup, the two‐step test concept is described: first, the specimen will be subjected to random loads obtained by a certain power spectral density for an amount of time which should nominally cause a 30% of damage; then, the fatigue test will be ended on a resonance testing machine to compute the actual residual fatigue life of the specimen; this two‐step testing also allows to reduce the time requested for the tests. The test bench developed for the experimental investigation is described in the paper, together with the results of some preliminary tests, aimed at verifying the feasibility of the conceived procedure. [ABSTRACT FROM AUTHOR]

The axle spring vibration isolator rubber installed on the axle box that encloses the axle bearings is subjected to loads corresponding to the wheel weight and vibration of the axle box during running. It is thought that the running condition of the bogie can be monitored by utilizing the axle spring vibration isolator rubber as a sensor to grasp the load and vibration. Therefore, we investigated a method of monitoring the running condition of the bogie by incorporating a piezoelectric element, which generates electric signals in response to applied loads and vibrations, in the axle spring vibration isolator rubber. In this paper, we made the rubber isolator with a built-in piezoelectric element (RIBP). As a result of running tests with the RIBP installed on a bogie, we found that the running condition of the bogie can be monitored by the time waveform of the electrical signal obtained from the piezoelectric element, and that the condition of the axle bearing can be monitored by the result of frequency analysis. In addition, as a result of examining the actual method of monitoring the running condition of a bogie using a RIBP, it was found that the condition could be monitored even if the number of RIBP installed on the bogie was reduced.

Recently, most video-based person re-identification (Re-ID) methods adopt complex model or multi-scaled information to explore more discriminative spatio-temporal clues, thus achieving better retrieval accuracy. However, we witness that these approaches involve significant higher computation costs but only improve limited performances. Therefore, the overarching goal at this stage is to solve video Re-ID on the trade-off between accuracy and efficiency, thereby boosting the application in real scenarios. Frequency transform provides advantages of simplified representation, identification of hidden information and noise filtering in signal processing. Motivated by this, we treat the complex spatio-temporal feature as signal and convert it to frequency domain. By directly analyzing frequency clues, complex feature extraction procedures can be avoided. Specifically, this paper proposes a novel paradigm by categorizing video features into low/high and spatial/temporal frequency information. Then, with the help of 3D DCT, we theoretically establish the transform equivalence relationship between spatio-temporal domain and frequency domain. Finally, this paper proposes a simple and intuitive Frequency Information Disentanglement Network (FIDN) for video Re-ID. By extracting and applying both low and high frequency spatio-temporal features from a disentangling way, FIDN achieves comprehensive and discriminative video representation. Extensive experiments indicate that FIDN reaches the state-of-the-arts with only one convolution layer addition against baseline. [ABSTRACT FROM AUTHOR]

Night-Time Scene Parsing (NTSP) is essential to many vision applications, especially for autonomous driving. Most of the existing methods are proposed for day-time scene parsing. They rely on modeling pixel intensity-based spatial contextual cues under even illumination. Hence, these methods do not perform well in night-time scenes as such spatial contextual cues are buried in the over-/under-exposed regions in night-time scenes. In this paper, we first conduct an image frequency-based statistical experiment to interpret the day-time and night-time scene discrepancies. We find that image frequency distributions differ significantly between day-time and night-time scenes, and understanding such frequency distributions is critical to NTSP problem. Based on this, we propose to exploit the image frequency distributions for night-time scene parsing. First, we propose a Learnable Frequency Encoder (LFE) to model the relationship between different frequency coefficients to measure all frequency components dynamically. Second, we propose a Spatial Frequency Fusion module (SFF) that fuses both spatial and frequency information to guide the extraction of spatial context features. Extensive experiments show that our method performs favorably against the state-of-the-art methods on the NightCity, NightCity+ and BDD100K-night datasets. In addition, we demonstrate that our method can be applied to existing day-time scene parsing methods and boost their performance on night-time scenes. The code is available at https://github.com/wangsen99/FDLNet. [ABSTRACT FROM AUTHOR]

This study investigates the envelopes of maximum flows based on maximum precipitation data in the Javita River basin. The objective is to provide relevant information for the design and management of water resources in the region. A methodology was employed, including the analysis of historical series of maximum precipitation, the estimation of occurrence probabilities, and the application of the rational formula. The results show adjustment coefficients for return periods ranging from 2 to 100 years, as well as envelope curves for areas from 0.1 to 1000 km². The importance of considering the limitations of the methodology and the need for further research to validate the results are highlighted. This study provides a solid foundation for future work in the field of Javita River basin hydrology and contributes to the understanding of extreme hydrological events in the region. [ABSTRACT FROM AUTHOR]

Frequency analysis has long been an important theme of hydrology research. Although meteorological techniques (physical approaches) such as radar nowcasting, remote sensing, and forecasting heavy rainfall events using meteorological simulation models are quite effective for urban disaster prevention, statistical and stochastic theories that include frequency analysis, which are usually used in flood control plans, are also valuable for flood control plans for disaster prevention. Master plans for flood control projects in urban areas often use the concept of T-year hydrological values with a T-year return period. A flood control target is a "landside area that is safe against heavy rainfall or floods with a return period of T years". This review emphasizes discussions of parameter estimation of stochastic models and selection of optimal statistical models, which include evaluation of goodness-of-fit techniques of statistical models. Based on those results, the authors criticize Japanese standard procedures recommended by the central government. Consistency between parameter estimation and evaluation of goodness-of-fit is necessary. From this perspective, we recommend using the maximum likelihood method and AIC, both of which are related to Kullback–Leibler divergence. If one prefers using SLSC, we recommend not SLSC itself but SLSC's non-exceedance probability. One important purpose of this review is the introduction of well-used Japanese methods. Because some techniques that are slightly different from the international standard have been used for many years in Japan, we introduce those in the review article. [ABSTRACT FROM AUTHOR]

The paper presents the results of static and dynamic experimental tests conducted on historical heritage structures and sculptures. In recent years, there was an increasing need to address the behaviour of these types of structures due to several reasons. Diagnosing the actual condition of a historical structure involves not only identifying the cause of a detected defect, but also determining its impact and assessing whether the structure can continue to perform safely. This article utilises unconventional loading methods to generate measurable mechanical responses. In one case, a lifting procedure is employed to study strains in a composite structure, while in another example, the mass and movement of people are used as a form of loading. Proof load tests conducted on a monumental sculpture allowed for the determination of load distribution among its heterogeneous structural components, namely a bronze shell and an iron reinforcing frame. Furthermore, the static and dynamic loading of a ceiling supported by a masonry vault demonstrated its ability to withstand anticipated loads resulting from unconventional use as a temporary exhibition space. [ABSTRACT FROM AUTHOR]

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Tourism is becoming more and more personalised. New types and forms of tourism are gradually emerging. One of them is dynamically developing cultural tourism which represents trips to tangible and intangible cultural heritage with discovery and learning objectives. The basis of the development of cultural tourism is a sufficient offer resulting from cultural heritage and it also depends on the quality of the service provided which ultimately leads to the satisfaction of visitors to these objects. As part of the research, satisfaction with the visit was evaluated using frequency analysis at three UNESCO heritage sites (Litomyšl Castle, Lednice Castle, Kroměříž Castle). Satisfaction was identified based on 1.500 reviews on the Google.cz portal. for the period 1/2022 to 6/2023. One of the outputs of the research is the creation of a frequency map of the identified key concept expressions of customer reviews. On the basis of the research results, it can be concluded that visitors are above average satisfied with the offer. Words like "comment", "beautiful", "nice", and "lock" are most often found in reviews. [ABSTRACT FROM AUTHOR]

In this article, the frequency characteristics of the forces and torques in the various cycloidal gearbox designs were investigated. The aim of the article is the search for frequency patterns that could be used in the formulation of a fault diagnosis methodology. Numerical analysis was performed in the cycloidal gearbox without defects as well as in cycloidal gearboxes with lobe defects or with removed lobes. The results of the numerical analysis were obtained in the multibody dynamics model of the cycloidal gearbox, implemented in Fortran and using the 2nd-order Runge-Kutta method for the integration of the motion equations. The used model is planar and uses Hunt and Crossley's nonlinear contact modelling algorithm, which was modified using the Heaviside function and backlash to fit cycloidal gearbox model convergence demands. In the analysis of fault diagnosis methods, the coherence function and Morris minimum-bandwidth wavelets were used. It is difficult to find a unique pattern in the results to use in the fault diagnosis because of the random characteristics of the torques at the input and output shafts. Based on obtained results, a promising, low-vibration cycloidal gearbox design with removed 7 lobes of the single wheel was studied using the FFT algorithm. [ABSTRACT FROM AUTHOR]

Current challenges in collecting and analyzing subway vibration data include the absence of standardized data collection methods, limitations in data analysis techniques, and an unclear understanding of the effects of geological conditions on vibrations. This study investigated vertical vibrations of tunnel walls and the ground above tunnels under different geological conditions of soft soil and rock strata at horizontal distances of 0, 15 m, and 30 m from the tunnel center line during train passages. The collected data underwent Fourier transformation and 1/3 octave processing to extract spectral characteristics and analyze transmission losses across different frequency bands. Our findings revealed two vibration peaks in the transmission process for both soft soil and rock formation geology. Specifically, high-frequency vibrations in soft soil experienced greater attenuation when transmitted from the tunnel wall to the ground at 0 m, while low-frequency vibrations in rock formations showed greater attenuation. We also observed a vibration amplification phenomenon at 15 m under soft soil geology conditions. Although low-frequency vibrations below 12.5 Hz showed slight attenuation within a 30 m test distance under both geological conditions, vibrations above 40 Hz experienced significant attenuation. These results offer valuable insights for reducing vibrations in subway superstructures and planning subway lines under diverse geological conditions. Furthermore, this study serves not only as a basis for mitigating vibrations in metro spans and designing metro lines in various geological contexts but also establishes a scientific foundation for future research.

This study aims to validate a piezoelectric driven-rod scour monitoring system that can sense changes in scour depth along the entire rod at its instrumented location. The proposed sensor is a polymeric slender rod with a thin strip of polyvinylidene fluoride that runs through its midline. Extraction of the fundamental frequency allows the direct calculation of the exposed length (or scour depth) of the slender rod undergoing fluid flow excitation. First, laboratory validation in dry conditions is presented. Second, hydrodynamic testing of the sensor system in a soil-bed flume is discussed. Each rod was installed using a three-dimensional-printed footing designed for ease of installation and stabilization during testing. The sensors were installed in a layout designed to capture symmetric scour conditions around a scaled pier. In order to analyze the system out of steady-state conditions, water velocity was increased in stages during testing to induce different degrees of scour. As ambient water flow excited the portion of the exposed rods, the embedded piezoelectric element outputted a time-varying voltage signal. Different methods were then employed to extract the fundamental frequency of each rod, and the results were compared. Further testing was also performed to characterize the relationship between frequency outputs and flow velocity, which were previously thought to be independent. In general, the proposed driven-rod scour monitoring system successfully captured changing frequencies under varied flow conditions.

Abstract Background The respiratory system’s static compliance (C rs) and airway resistance (R rs) are measured during an end-inspiratory hold on volume-controlled ventilation (static method). A numerical algorithm is presented to calculate C rs and R rs during volume-controlled ventilation on a breath-by-breath basis not requiring an end-inspiratory hold (dynamic method). Methods The dynamic method combines a numerical solution of the equation of motion of the respiratory system with frequency analysis of airway signals. The method was validated experimentally with a one-liter test lung using 300 mL and 400 mL tidal volumes. It also was validated clinically using airway signals sampled at 32.25 Hz stored in a historical database as 131.1-s-long epochs. There were 15 patients in the database having epochs on volume-controlled ventilation with breaths displaying end-inspiratory holds. This allowed for the reliable calculation of paired C rs and R rs values using both static and dynamic methods. Epoch mean values for C rs and R rs were assessed by both methods and compared in aggregate form and individually for each patient in the study with Pearson’s R 2 and Bland–Altman analysis. Figures are shown as median[IQR]. Results Experimental method differences in 880 simulated breaths were 0.3[0.2,0.4] mL·cmH2O−1 for C rs and 0[− 0.2,0.2] cmH2O·s· L−1 for R rs. Clinical testing included 78,371 breaths found in 3174 epochs meeting criteria with 24[21,30] breaths per epoch. For the aggregate data, Pearson’s R 2 were 0.99 and 0.94 for C rs and R rs, respectively. Bias ± 95% limits of agreement (LOA) were 0.2 ± 1.6 mL·cmH2O−1 for C rs and − 0.2 ± 1.5 cmH2O·s· L−1 for R rs. Bias ± LOA median values for individual patients were 0.6[− 0.2, 1.4] ± 0.9[0.8, 1.2] mL·cmH2O−1 for C rs and − 0.1[− 0.3, 0.2] ± 0.8[0.5, 1.2] cmH2O·s· L−1 for R rs. Discussion Experimental and clinical testing produced equivalent paired measurements of C rs and R rs by the dynamic and static methods under the conditions tested. Conclusions These findings support to the possibility of using the dynamic method in continuously monitoring respiratory system mechanics in patients on ventilatory support with volume-controlled ventilation.

Abstract In this paper frequency analysis of annual extreme daily rainfall of 14 gauging stations located in an arid zone of Iran were performed using parametric and nonparametric approaches. The parametric methods include normal, two- and three-parameter log-normal, two-parameter gamma, Pearson and log-Pearson type III, extreme value type I (Gumbel), generalized extreme value and generalized logistic distributions. The nonparametric approach is Fourier series method. The data were fitted to all of above mentioned models and the results showed that the goodness of fit of the data to Fourier series is much better than other parametric methods. Thus the Fourier series can be used as an alternative approach for frequency analysis of extreme daily rainfall in an arid zone. In addition, the quantiles can be calculated by the Fourier series.