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Kochi city in southern India periodically experiences waterlogging or urban floods due to unabated urban growth and extreme rainfall events. This study aims to mitigate urban flood hazards through green infrastructure (GI) and its effective management. Assessment of storm water runoff (SWR) modeling is carried out in four scenarios, viz., baseline, past, severe, and green, using urban growth and GI driven simulations. Urban growth modeling and GI suitability analysis are carried out using Cellular Automata Markov (CA-Markov) and urban planning guidelines, respectively. The study provides insights into how GI influences SWR reduction and urban environment conservation, with 16% SWR reduction as compared to the baseline scenario and 18% when compared to the severe scenario. [ABSTRACT FROM AUTHOR]

Various empirical methods have evolved over the years in South Africa to estimate either design floods, design rainfall, catchment response time, and/or Areal Reduction Factors (ARFs). The verification of any empirical method requires the use of observed data not used during the calibration process, while observed data is also required for validation purposes. In the case of ARFs, which are used to convert average design point rainfall depths to an areal (catchment) design rainfall depth, all the calibration/verification data sets remain only estimated sample values of design rainfall. Subsequently, this paper presents an independent application and validation of the regional geographically-centred ARF method (Pietersen 2023) against the currently recommended geographically-centred ARF method (Alexander 2001) by incorporating the different ARF estimates into the Rational Method (RM) to highlight the impact thereof on the resulting flood estimates. In applying a ranking-based goodness-of-fit selection procedure, the RM in combination with the newly derived regional geographically-centred ARF method (Pietersen 2023) resulted in the best deterministic flood estimates when compared to the at-site statistical flood peaks. Apart from the ARFs, catchment response time, design rainfall, and weighted runoff coefficients are all regarded as key input parameters for design flood estimation in ungauged catchments. [ABSTRACT FROM AUTHOR]

The time of concentration is an important concept in hydrology. It provides a characteristic hydrological response time (CHRT) useful in many applications. Estimation of the time of concentration is challenging because small watersheds (<100 km2) with sub-daily flow and precipitation records are uncommon. Many practitioners therefore use empirical equations developed from watersheds exposed to different climates and with different attributes. The main objective of this study is to develop an approach to estimate the CHRT from physiographic characteristics for small watersheds located in Ontario, Québec and the northeastern USA. Regression trees are used to identify the physiographic characteristics associated with CHRT. The fraction of lakes and wetlands was identified as the most significant attribute related to CHRT, followed by the ratio between the main watercourse length and the square root of the main watercourse slope. Uncertainties on estimated CHRT values based on regression tree are also provided. [ABSTRACT FROM AUTHOR]

Kochi city in southern India periodically experiences waterlogging or urban floods due to unabated urban growth and extreme rainfall events. This study aims to mitigate urban flood hazards through green infrastructure (GI) and its effective management. Assessment of storm water runoff (SWR) modeling is carried out in four scenarios, viz., baseline, past, severe, and green, using urban growth and GI driven simulations. Urban growth modeling and GI suitability analysis are carried out using Cellular Automata Markov (CA-Markov) and urban planning guidelines, respectively. The study provides insights into how GI influences SWR reduction and urban environment conservation, with 16% SWR reduction as compared to the baseline scenario and 18% when compared to the severe scenario.

Trapezoidal hyetographs are common in both real-world small watersheds and laboratory watersheds because (1) real-world hyetographs are often represented by line charts that can be divided into multiple trapezoidal rainfall pulses, and (2) laboratory rainfalls are usually generated by rainfall simulators uniformly in space and time, but when considering infiltration loss, the excess hyetographs may be approximated to be trapezoidal. Particularly, a trapezoidal hyetograph can be converted to a runoff hydrograph simply, accurately, and theoretically based on the general unit hydrograph model. The objective of this research is thus to test the theoretical trapezoidal hyetograph method with laboratory watershed rainfall-runoff data. The results showed that this theoretical method agrees very well with laboratory watershed data, with determination coefficients r2>0.93 for both constant and variable (incident) rainfall intensities. Therefore, the trapezoidal hyetograph method can be used to convert any line-chart hyetograph to a runoff hydrograph analytically, where rectangular and triangular hyetographs are special cases. Finally, the trapezoidal hyetograph method for a constant excess rainfall intensity (or the general rational method) is comparable to the classic kinematic wave theory for overland flow, but it is much simpler in applications. [ABSTRACT FROM AUTHOR]

One of the key issues in assessing possible flood hazards is the estimation of runoff coefficient, i.e. the amount of rainfall transformed into runoff. This study aims to estimate peak runoff coefficients using two approaches. The indirect approach based on the rational formula was applied in 29 small catchments in Slovakia. A direct approach based on the analysis of observed rainfall-runoff events was used in one of them as well. The rainfall intensity used in the indirect method was estimated by three different techniques. The Horné Orešany - Parná catchment was chosen to compare the peak discharge coefficients from the indirect and the direct estimations. The results showed that the indirect approach often resulted in high or unrealistic peak runoff coefficients. The study contributes to understanding the variability in estimating peak discharge coefficients for small catchments and their use in engineering practice. [ABSTRACT FROM AUTHOR]

Purpose With the aid of the rational method (al-manhaj al-'aqly), which prioritizes reason and mantic principles while focusing on logical argument, this study attempts to an understanding of prophet Ibrahim's style of preaching. Method This study used a library research design and thematic method. This research method uses aspects of library research with data according to books and literacy related to rational method, tafsir fii dzilalil Qur’an and include various of Sayyid Quthub's writings Results/findings This study reveals the prophet Ibrahim's method of rational da'wah by applying the interpretation of the fii dzilalil Qur'an to the as follows: 1) The prophet Abraham's celestial arms proof of God; 2) The destruction of their idols, which served as the root of their error; 3) The prophet Ibrahim's rational da'wah to his father Azar using very polite and rational language; 4) The prophet Ibrahim's rational debate with the king in Surah Al-Baqarah verses 258 Conclusion In particular, the numerous preachers who rely on and use the logical da'wah taught by the prophet Ibrahim have had a significant impact on both classical and current da'wah approaches. The prophet Ibrahim used rational da'wah in calling on his father and humanity.

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In this work the attenuation potential of flood peaks of 265 large reservoirs all over Italy is analysed, considering a flood management that excludes gates opening and then configures strictly unsupervised attenuation effects. Key factors of dams and related basins are considered to develop a ranking method that can emphasize the interplay between dam geometry and the hydrological processes acting in the upstream watershed. To maintain a homogeneous approach in such a wide geographic area, the attenuation index is computed applying the numerical solution of the differential equation of lakes and only two different standardized hydrograph shapes have been used. An index design flood from the rational method is used as the incoming peak value for each dam, enhancing the use of the results of a recent analysis of all Italian rainfall extremes. Even with a very simple approach, twenty-four different design incoming floods are derived, by varying the shape of the incoming hydrograph and the parameters of the rational method. Exploring the ranking results in all the alternatives, the attenuation potential obtained for all dams demonstrates to be strongly sensitive to the assumptions on the time of concentration and to some rainfall features. On the other hand, the hydrograph shape seems to exert much less influence on the ranking outcome. Results obtained can be useful to studies of wide-area flood frequency analyses, as we highlighted the sensitivity of the rank of attenuation efficiency to hydrologic parameters widely used in the assessment of the design flood peaks in ungauged basins. [ABSTRACT FROM AUTHOR]

Background: The surface runoff created by rainfall is essential to recharge the Gaza coastal aquifer with fresh and clean water when adequately collected and infiltrated. Thus, accurate estimation of surface runoff can foretell the actual volume of incoming stormwater to the infiltration basin. Method: There are several methods for calculating rainfall-runoff only a few of them are accurate due to various restrictions and limitations. Rational formula was used to calculate the surface runoff entering Waqf infiltration basin located in Gaza city. Results: The daily surface runoff was estimated as 265,320 m³ using the Rational method while it was 324,000 m³ using the Soil Conservation Service (SCS) method at 67 mm rainfall depth for 5 year return period. Whereas, at 10 mm rainfall depth during the 2021-2022 wet season, a large difference was determined between the two methods. Thus, in-situ estimation was used as a third method, in which the water height in Waqf basin's grit removal chamber was measured, thereby calculating the daily surface runoff as 360 m3 which was not far from the result obtained by the SCS method at 10 mm daily rainfall depth. Conclusion: It was concluded that using a reliable method was very important for the accurate estimation of surface runoff, which leads to a well-designed infiltration system in the Gaza strip. [ABSTRACT FROM AUTHOR]

Water plays a vital role in all living organisms on earth. With rapid urbanization, water is exploited at a greater pace than any other natural resource. The unavailability of water for all basic needs is at great risk. An optimization approach was developed to identify optimal sub-catchment with maximum runoff to implement Artificial Ground Recharge Points (AGRP) to raise the water groundwater table to mitigate the above-stated problem. This research focuses on developing an AGRP in the Noyyal River basin sub-catchments in Coimbatore city of Tamil Nadu, India. The methodology consists of three phases; in the first phase, the data for the work are collected from various sources. In the next phase, the data are pre-processed to convert various data formats to a standard format for easy processing. In the third phase, the pre-processed data are passed as an input to the genetic algorithm, the fuzzy logic is used as a fitness function to effectively calculate the rainfall-runoff events of each sub-catchments. The rules for calculating rainfall-runoff are carried out at three levels, as the first level, the area of influence in each sub-catchment by each rain gauge station is calculated to assign the rainfall values. In the second level, the area of influence and Land Use/Land Cover (LULC) classification for each sub-catchment is carried out to assign runoff co-efficient for each classification. As the final level, area of influence, LULC, and soil classification for each sub-catchment were carried out to calculate the infiltration rate. The classified data are passed as an input to calculate the rainfall-runoff for each sub-catchments for a period of eleven years (2010–2020) is done. The optimal sub-catchments with maximum runoff are obtained. The assessment of rainfall-runoff events for various sub-catchments in the study region indicates water flow in the streams. The long flow of streams into the city results in fresh rainwater being contaminated, contributing to groundwater contamination. The GA-FUZZY provides optimal sub-catchments to establish AGRP to use rainfall water effectively. The outcome of the work is a scalable methodology that can help the Public Works Department to implement AGRP in various river basins to increase the water table. [ABSTRACT FROM AUTHOR]

Flash flood is among the most catastrophic hazards worldwide. Jordan has been witnessing unusual shocks of flash floods with regular intervals. It is best described as sudden events involving 'too much water in too little time'. This study aims at presenting flash flood assessment and producing a potential flood hazard severity map. The GIS-based hydrology assessment was carried out using Rational model. The model integrates biophysical characteristics of the basin and the hydrometrological information. The range of peak discharge was around 5 MCM in the Jordan Valley to 65 MCM in W. Hammad basin. Flood hazard severity map was produced based on Integrated Context Analysis approach (ICA) at surface basin's level. It has been shown that 17.6% of Jordan's area is categorized into 'high' class hazard severity. The study provides consistent information at a national-scale on flood hazard reclassification to support the development of the implementation of flood management policy of flood mitigation activities. Also, it proves the usefulness of GIS technology in model preparation and parameterizations. [ABSTRACT FROM AUTHOR]

It is time to shift our paradigm of small watershed design from a graphic (or tabular) to a theoretical method, because (1) the recent general unit hydrograph (UH) model can convert a design hyetograph to a design hydrograph simply, accurately, and theoretically; (2) the Natural Resources Conservation Service (NRCS) has recommended that the National Oceanic and Atmospheric Administration (NOAA) Atlas 14 rainfall data of depths and distributions at a specific site, which is often called the NRCS-NOAA rainfall distributions, should be used for small watershed design if runoff data are unavailable; and (3) in this paper, we have presented a design procedure that formulates design hydrographs from the NRCS-NOAA Atlas 14 rainfall distributions and the general UH model automatically, using the MATLAB convolution function. A literature review indicated that the current practice for design hydrographs in small watersheds from hyetographs is laborious because both hyetographs and UHs are discrete. By contrast, the theoretical general UH model can significantly simplify this process. In this research, we first found analytic design hydrographs from rectangular and triangular hyetographs, which were next used to validate the MATLAB convolution method. We then proposed a double exponential rainfall distribution for both asymmetric and symmetric hyetographs. After that, we modified the symmetric exponential distribution model to describe NRCS-NOAA Atlas 14 data for site-specific hyetographs, which are finally convolved with the general UH model for site-specific design hydrographs, using the MATLAB convolution function. It is noteworthy that the proposed method extends the classic rational method from the peak discharge to the whole hydrograph; and it is valid for both continuous and discrete hyetographs. Hence, it provides a powerful tool in urban development, agriculture land use, roadway planning, and airport construction; it can also be used to evaluate an existing drainage system under various meteorologic–hydrologic conditions. Finally, we expect that this research will shift our current design practice and university UH teaching from an empirical to a theoretical paradigm in the near future. [ABSTRACT FROM AUTHOR]

In this study, the risk analysis is used to determine the return period in which the design cost plus the damage risk cost is minimum. The damage includes the roads and traffic, the lawn areas, and the residential and commercial buildings. The traffic damage is based on two factors, time of delay and social negative impacts. The nonlinear reservoir model is used to convert the rainfall into runoff and the dynamic wave model is utilized to perform the network hydraulic simulation in stormwater management model (SWMM) software. This model is defined as an appropriate model. This model was applied in the risk analysis of a region in Tehran to obtain the optimal return period design. The results indicated that the optimal return period is 10 years. The rational method was also applied to the same region and same return period, but the total design cost of the rational method was greater by 5%. The damage due to the traffic include financial damages due to delays and loss of fuel resources in addition to the dissatisfaction of people due to the psychological burden. HIGHLIGHT In this study, risk analysis is used to determine the return period in which the design cost plus the damage risk cost is minimum. The damage included the roads and traffics, the lawn areas, and the residential and commercial buildings. The traffic damage is based on two factors, time of delay and social negative impacts.;

Kelapa Gading is one of the sub-districts in North Jakarta that is often hit by floods, so it is necessary to analyze the causes of flooding and how to overcome them. According to the calculations performed using the Manning Formula, whose results then compared with the planned discharge calculated using the Rational Method, it is established that there are 18 channels from 33 drainage channels which are unable to accommodate runoff discharge that may occur within a 5-year period. Thus, for a period of 10 years, there are 20 channels that are unable to accommodate the existing runoff discharge. Furthermore, from 10 Pumping Stations in a ten years rainy period, there are four pumps that are unable to accommodate runoff discharge with the assumption of 0.2 m inundation. Meanwhile, assuming a 0.5 m inundation, there are seven pumps that cannot accommodate the existing runoff discharge. Therefore, suggestions that can be given to reduce flooding in Kelapa Gading are to enlarge the existing drainage channel and add pumps according to the recommendations. Lack of land infiltration also causes flooding therefore, it is necessary to build 617infiltration wells which are constructed at various points in Kelapa Gading thus making flooding does not occur again.

The flood peak is commonly estimated using the rational method for the design of hydraulic structures. The method is mainly used in a deterministic context. However, there is often uncertainty in flood predictions, which should be incorporated in the design of mitigation schemes. This research proposes a methodology to cope with uncertainty in the rational method via the application of a stochastic framework. Data from 158 storms, recorded in the period 1984–1987 in 19 subbasins in the southwestern part of Saudi Arabia, were used to implement the proposed methodology. A tri-variate log-normal probability density function was used to model the joint relationship between the rational method parameters. The model considered the parameters as random variables. The uncertainty in the rainstorms was represented by intensity or depth; the uncertainty in basin delineation (due to the use of different digital elevation model resolution) was represented by the basin area; and the uncertainty in the land use/land cover was represented by the runoff coefficient. The Monte Carlo method was used to generate realizations of the peak flow and runoff volume with 95% and 99% confidence levels from the input parameters. Although the correlation between the parameters was weak, the model was capable of simulating the rational model parameters and estimating the peak flow and runoff volume relatively well, and the generated realizations fell within the confidence levels, except for a few marginal cases. The model can be used to generate peak flows and the associated confidence limits in ungauged basins from the statistics of the input parameters using the equations developed in this study. [ABSTRACT FROM AUTHOR]

Study region: Peninsular Spain. Study focus: There is strong evidence that climate change has produced a decrease in precipitation combined with an increased frequency, intensity and magnitude of high-intensity storm events in Peninsular Spain. Such events have been particularly recurrent on the Spanish Mediterranean coast in recent years. This study’s first objective is to update the trends in the magnitude and seasonality of precipitation in Spain from 1951 to 2019 at different time scales. Secondly, we analyse how extreme precipitation events recorded in recent years can modify water infrastructure design flows. A QGIS plugin was programmed using Python to calculate the design flows in accordance with the methodologies legally established in Spain. New hydrological insights for the region: The results confirm the decreasing trend in annual precipitation in most of the Spanish territory. This decrease was particularly significant during March and June. Moreover, the average increases of around 30–40 % in design flows, which reached double the values obtained in the reference period of 1951–1990 in some basins, confirm the relevance of incorporating high-intensity storm events recorded in recent years into flow calculations in Peninsular Spain. Design flows obtained without using the most recent rainfall data can be underestimated, with profound risk implications. Therefore, there is a sufficient technical basis to draw attention to this problem and recommend its formal consideration by competent authorities.

Gluten is produced from wheat grains and is used in the food industry as an improver in flour baking properties. On the basis of a comparative analysis of the methods of dehydration of frozen granules of wheat gluten with a surface dry crust, a rational method of drying them in a fluidized bed has been selected. In the process of calculating units with a fluidized bed, its hydrodynamic parameters have been determined: loss of the pressure of the fluidizing agent; the speed at the transition of the bed from the state of rest to the pseudo-boiling mode; layer porosity; the rate of entrainment of particles in unrestricted conditions roughly corresponding to the rate of soaring, at which a single particle is in equilibrium in the gas flow. During the dewatering operation, the rate of entrainment of the granules varies; therefore, it is advisable to use the passing fluidization mode depending on the decrease in their moisture content. In the variant of the active hydrodynamic regime in the drying unit, the dehydration procedure is intensified without a noticeable decrease in the economic efficiency of its functioning and high quality indicators of the finished product with the given final moisture are provided, which is due to the specific conditions of contact of the granules with the coolant. For granules with a moisture content of 0.19 kg/kg, the values of hydrodynamic characteristics have been determined: the area of critical pseudo-boiling rates is 4.1–5.5 m/s; the carryover rate of the fines is 12.5–14.5 m/s. As a result of the study, the choice has been substantiated in favor of drying the studied granules in a fluidized bed due to the prevalence of its advantages over the dehydration of the object in drum dryers.

The aim of this study is to investigate the response of the rational method in flood hazard assessment in Potamia watershed of Thasos island, with climate data from Regional Climate Models. The precipitation intensity–duration–frequency (IDF) curves used were calculated using available EURO-CORDEX 0.11 regional climate model simulations, under the RCP8.5 scenario. The Corine Land Cover dataset was utilized for the determination of the runoff coefficient of the watershed and geomorphological and hydrographic characteristics are calculated using a Geographic Information System software. A comparison against actual flood events of the period 1991–2019, as mapped with satellite Synthetic Aperture Radar (SAR) imagery, is also carried out.

In Islamic culture, rationality and the implementation of the secondary meanings for rationality and wisdom have a unique interpretation in Islam that is not comparable to other religions and cultures. Rationalism has such a high status in Islamic jurisprudence that Islamic rationalism is complete. Islam considers moral education as the leading foundation for a complete education. Therefore, rational education is parallel to moral education. Moral education is the guidance and education of the human psyche through the rational side. In rational education, the heart of man is the center of rationalism. The heart of every human is educated through the verses of the Qur'an and the hadiths of the Imams. Therefore, the social structure of an Islamic society is endowed with an infinite moral aspect that stabilizes man's situation in society and clarifies his relationship with society - the demands and conditions of the new situation guide the individual and society to grow. According to Nahj-Al-Balaghah, optional behavior is attributed to a human being. A wise person is expected to improve and develop the compelling aspects of rationalism and guard against inhibiting factors of rationalism. Therefore, the wise person can appropriately benefit from the achievements of forward-looking action and begin a life of happiness and pride. In many narrations of Imam Ali (A.S.) about the qualities of wisdom and the forward-looking wise man, wisdom is the most vital source to recognize truth and falsehood and perform good deeds. This paper examines the role of rationalism and thoughtfulness in educating the moral society through the hadiths of Imam Ali (A.S.). [ABSTRACT FROM AUTHOR]

Digital humanities is not only a particular approach in research but also a methodology of holistic significance. Although the field of literary studies engages the methodology of digital humanities, more critical reflections upon it are needed. This article proposes a four-layered interrogation about the methodology of digital humanities so as to enhance such critical reflections. The interrogations are as follows. First, we may find that digital humanities involves such questions as autonomy and legitimation through interrogating the history of intellectual thought. Second, we can find existential experience of disorientation and rational hubris in our age through interrogating the emotion of the time. Third, we can discover the digital objects and digital experience underlying the methodology of digital humanities through ontological interrogation. Finally, we can reveal the transformation from the subject of production to that of research through interrogating subjectivity. [ABSTRACT FROM AUTHOR]

Climate change combined with urbanization increases the performance demand on urban drainage systems. Green roofs are one of the most used green infrastructure measures to alleviate the pressure on the urban drainage system through the detention and retention of runoff. The rational method with the runoff coefficient (C) is one of the most commonly used design tools for stormwater design in Norway. This method relies on a runoff coefficient being available for green roofs, which is typically not the case. This paper compares laboratory and experimental field studies to investigate runoff coefficients from different types of detention-based roofs. The methodology described in the German ‘FLL Guideline’, one of the world's most commonly used green roof standards, was used to measure the runoff coefficients for the different components making up a typical green roof. The contribution from each layer is reflected in the runoff coefficients. The runoff coefficients from the field experiments were calculated using observed precipitation and runoff from existing green roofs in Oslo, Trondheim, Sandnes, and Bergen, Norway. Events that had a cumulative precipitation comparable to the laboratory events, but longer durations, were selected. These events gave significantly lower and varying runoff coefficients, clearly demonstrating the limitation of choosing a suitable runoff coefficient for a given roof. However, laboratory experiments are important in understanding the underlying flow processes in the different layers in a detention-based roof.

Arid regions are suffering from the availability of streamflow data for reliable design of hydraulic structures. The rational method is a common method for peak discharge (Qp) estimation in the design of water structures since it is easy and needs a few parameters. However, the method is restricted to small basins of size less than 5 km2. Concerning such method, many objectives have been investigated in the current study. Two of the main targets are the validity of the application of the rational method for large watersheds in dry regions. Moreover, the method is extended to calculate the runoff volume (V). It has been found that the method can be applied for large basins that vary between 170 and 4930 km2. First-order-second moment sensitivity analysis is utilized to derive analytical expressions to relate the variability in Qp and V as a function of the variability of the runoff coefficient, rainfall intensity or depth, and basin area. Five basins with 19 subbasins in the southwestern of Saudi Arabia are analyzed with 160 storms recorded in the period (1984–1987). The design duration of the rainfall intensity that is used in the rational formula should be estimated based on the time of concentration (tc) calculated from the equation developed by (Albishi et al., Arab J Geosci 10:1–13, 2017) and not from (Kirpich, Civ Eng 10:362, 1940) as commonly used in the literature and Kingdom of Saudi Arabia flood studies. The former provides a minimum RMSE of 87.66 m3/s, while the latter has a RMSE of 168.41 m3/s. This suggests the use of (Albishi et al., Arab J Geosci 10:1–13, 2017) tc equation for a safer design, especially in this region and regions alike. The log-normal distribution fits well the hydrological variables based on the Kolmogorov–Smirnov test. Therefore, it can be utilized for the flood uncertainty analysis of these basins and similar ones. The first-order analysis shows quite reliable results since the variability of Qp ( σ ln Q ) and V ( σ ln V ) of the data (1.21 and 1.24), respectively, are pretty close to the developed expressions (1.3 and 1.24). [ABSTRACT FROM AUTHOR]

The paper presents the results of a case study that was prepared as a basis for decision-making processes in the context of the impacts of global climate change. The article is focused on a very important part of the urban environment, namely urban forests. When taking planning measures in periurban forests, two realities must always be addressed, i.e., adaptation measures to mitigate the effects of climate change on the forest complex in question and its use to mitigate the effects of climate change in its surroundings must both be considered. It is a well-known fact that forest communities (of any kind) are on the one hand affected by the impacts of climate change, but on the other hand are able to mitigate its effects on their surroundings. The case study was of land near the town of Mladá Boleslav. The aim was to analyse the hydrological regime of the Štěpánka Forest Park, nicknamed "the lungs of Mladá Boleslav". Modelling of the runoff coefficient was made for the whole park area, as well as for the part on the left bank of the Klenice River (forested part). The runoff conditions of the site and their subparameters are addressed in the study by comparing the current state with the modelled state after deforestation of the site, e.g., due to drought. As far as the spatial layout of the forest is concerned, it is absolutely essential to maintain an integrated stand on the site with a lower stem cover (fewer individuals per plot) and a lower regeneration period. These aspects of a growing matrix forest stand will ensure its sustainability, in particular the sustainable water management of the trees in the context of lower water reserves in the rhizosphere and the greater ability of younger individuals to adapt to changes in site conditions (replacement of stress-resistant types by resilient types). [ABSTRACT FROM AUTHOR]

Design flood is one of the important factors for flood risk assessment and water infrastructures planning and development in a certain location. There are several methods to estimate it, one method which has been commonly and widely use is using flood frequency analysis. This research aims to develop Intensity-Duration-Frequency (IDF) curves in Upper Werba Sub-Watershed, West Papua Province, Indonesia, to estimate design rainfall intensity. The design rainfall intensity is used to estimate peak of flood discharge using Rational Formula in the sub-watershed. Other methods, i.e. Soil Conservation Service and Nakayasu Synthetic Unit Hydrograph are also presented in this paper to provide comparison of the estimated peak of flood discharge. The result shows that the Rational method provide the closest magnitude of estimated flood discharge in Upper Werba Sub-Watershed to the observed streamflow. Therefore, it is suggested that the Rational method can be used for water infrastructure planning and development in the sub-watershed.

The article discusses the effectiveness of using innovative teaching methods in the educational process, as one of the important aspects in teaching the Russian language to a foreign-language audience. Particular attention is paid to innovative "learning technologies", the use of which contributes to the intensification and, therefore, optimization of the entire educational process. [ABSTRACT FROM AUTHOR]

Gea Craft is a small business engaged in the production various types of woman's bag from cow leather up to aged fiber with make to order production system. Leather cutting worker state feels discomfort when working and often get pain complaints from some parts of his body. It impacts to disrupt work activities and normal activities. The research aims to improve the working posture of leather cutting and accelerate the time required for process of cutting the leather by designing leather cutting machine by using rational methods. The results of this research is a leather cutting machine design which can cut the risk level from assess work posture by Rapid Entire Body Assessment (REBA) method that decreases the score become 1 (there is no significant risk) and decrease the time process of leather cutting to 26.264%.

In this paper, a class of rational methods of second to fourth order of accuracy are presented. The methods are developed by considering the concept of the closest points of approximation in its formulas. These methods require the application of a suitable method to calculate the starting approximation values as they are not self-starting, as well as higher derivatives of the problems. The illustrated region of absolute stability presented in the article shows that the rational schemes are all A-stable. The methods are tested on several initial value problems including systems of differential equations. From the numerical results, it appears that the proposed methods are comparable to some of the existing methods in terms of accuracy and efficiency. The capability of the schemes in solving problems whose solution possesses singularity and singularly perturbed problem can be obviously seen as they are compared to the existing rational multistep methods. The methods also show its reliability in solving stiff problems. Besides that, the schemes are tested on the Van der Pol's equation, which usually arises in physics and chemical reactions. The presented numerical solutions show that the proposed methods are comparably accurate to the existing methods. [ABSTRACT FROM AUTHOR]

Drowning fatalities in traffic accidents often occur at roadway sag curves or depressed sections. An increasing concern is how to quickly and safely remove the stormwater from low points of urban area roadways. In accordance with the green concept of Low-Impact-Development, in which a drainage system is designed to pass the full spectrum of runoff flows, this paper presents a new algorithm to improve the highway underpass drainage design for both safety and hydraulic efficiency. It is recommended that the underpass drainage facility be composed of two systems: an underground sewer line be sized to collect the minor storm event through gravity and a pump system be prepared to lift the excess water during a major storm event. Although the pump system in practice may be a permanent station or a mobile unit, the pump system prepared for a highway underpass must be documented in the emergency operational instructions. To design such a drainage system for multiple storm events, all individual drainage elements are to be sized individually, and then the entire drainage system must be evaluated under the tailwater effects. In this paper, a design example is presented to illustrate how to apply two hydrologic methods, including the rational method used to size the sewer pipes and sump pumps and the EPA Storm Water Management Model 5 was adopted to verify the performance of the proposed system under minor and major storm events, respectively. [ABSTRACT FROM AUTHOR]

Climate change combined with urbanization increases the performance demand on urban drainage systems. Green roofs are one of the most used green infrastructure measures to alleviate the pressure on the urban drainage system through the detention and retention of runoff. The rational method with the runoff coefficient (C) is one of the most commonly used design tools for stormwater design in Norway. This method relies on a runoff coefficient being available for green roofs, which is typically not the case. This paper compares laboratory and experimental field studies to investigate runoff coefficients from different types of detention-based roofs. The methodology described in the German 'FLL Guideline', one of the world's most commonly used green roof standards, was used to measure the runoff coefficients for the different components making up a typical green roof. The contribution from each layer is reflected in the runoff coefficients. The runoff coefficients from the field experiments were calculated using observed precipitation and runoff from existing green roofs in Oslo, Trondheim, Sandnes, and Bergen, Norway. Events that had a cumulative precipitation comparable to the laboratory events, but longer durations, were selected. These events gave significantly lower and varying runoff coefficients, clearly demonstrating the limitation of choosing a suitable runoff coefficient for a given roof. However, laboratory experiments are important in understanding the underlying flow processes in the different layers in a detention-based roof. [ABSTRACT FROM AUTHOR]

The paper presents the results of a case study that was prepared as a basis for decision-making processes in the context of the impacts of global climate change. The article is focused on a very important part of the urban environment, namely urban forests. When taking planning measures in periurban forests, two realities must always be addressed, i.e., adaptation measures to mitigate the effects of climate change on the forest complex in question and its use to mitigate the effects of climate change in its surroundings must both be considered. It is a well-known fact that forest communities (of any kind) are on the one hand affected by the impacts of climate change, but on the other hand are able to mitigate its effects on their surroundings. The case study was of land near the town of Mladá Boleslav. The aim was to analyse the hydrological regime of the Štěpánka Forest Park, nicknamed “the lungs of Mladá Boleslav”. Modelling of the runoff coefficient was made for the whole park area, as well as for the part on the left bank of the Klenice River (forested part). The runoff conditions of the site and their subparameters are addressed in the study by comparing the current state with the modelled state after deforestation of the site, e.g., due to drought. As far as the spatial layout of the forest is concerned, it is absolutely essential to maintain an integrated stand on the site with a lower stem cover (fewer individuals per plot) and a lower regeneration period. These aspects of a growing matrix forest stand will ensure its sustainability, in particular the sustainable water management of the trees in the context of lower water reserves in the rhizosphere and the greater ability of younger individuals to adapt to changes in site conditions (replacement of stress-resistant types by resilient types).

Any increase in impervious ground surfaces due to urban growth tends to intensify stormwater management problems. Partial urban flooding can occur any time when the volume of stormwater exceeds local drainage capacity. Phnom Penh has suffered from urban flooding for more than a decade because of the limited capacity of the city's drainage system. Numerous studies have investigated and proposed the use of green infrastructure (GI) as a tool for mitigating flooding due to stormwater runoff. The purpose of this study is to investigate the potential of proposed GI features for reducing stormwater runoff in central Phnom Penh. By using the Rational method, the peak discharge was analyzed and estimated for Tuol Svay Prei Pir, a central Phnom Penh neighborhood that experiences frequent flood problems. The runoff peaks produced by the current practices (S1), and the proposed practices that integrate with the GI features (S2) were compared. The results show that an increase in pervious surface up to 48.14% by implementing the four GI features; trees, bioswales, permeable pavements, and green roofs, the runoff rate will be reduced by 37.90%, which is equivalent to a reduction of 1.55 m³/s during peak runoff. [ABSTRACT FROM AUTHOR]

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In recent years surface runoff water harvesting is gaining more popularity in arid and semi-arid regions such as Afghanistan due to the increasing demand for scarce water resources. In Paghman District growing season starts in March and ends in October; however, in the latter half from June to October, it hardly rains, which causes crop failure and low productivity. So, collecting and stocking a certain amount of runoff water in the wet season and using it as irrigation water during the latter half of the growing season can reduce water shortage problems. Therefore, this study aimed to analyze water harvesting potentials through identifying suitable water harvesting sites and estimating the potential volume of surface runoff based on the rational method and the sorptivity method in the Qargha Watershed of Paghman District, Afghanistan. In this study, weighted overlay in GIS was used to determine suitable water harvesting sites. Sorptivity method and rational methods were used to estimate the volume of surface runoff. Based on the results of suitability analysis only 27.67% of the land was suitable for water harvesting. The estimated potential volume of surface runoff applied the rational method, and the sorptivity method was at 509.4 m3 and 478.3 m3. Therefore, it was concluded that water harvesting is possible in the study area. However, these estimated potential volumes of surface runoff needed to be calibrated with the observed data. [ABSTRACT FROM AUTHOR]

Romanian policy makers have to perceive that human intervention on river basins land cover is influencing rainfall-runoff relation and the used methodology cannot accurately estimate watershed surface flow transformations. Global water cycles and energy fluxes understanding is leading to better predictions of land atmosphere interaction and local hydro-climates evolution. The water transfer time determination from rainfall to runoff needs accurate measurements of river basins hydrological parameters. Here, we analyzed and compared the lag time value results of two different methodologies (curve number and rational methodology) used for 54 Romanian small catchment areas study. The focus of this paper is the lag time evaluation and interpretation for an effective implementation of the best methodology approach in the Romanian geographical space. Our research in small river basins was developed using remote sensing technology maps, GIS and environmental datasets in combination with field work on every drainage basin in order to assess the specific morphological features and validate the land cover typology. We found that Soil Conservation Service - Curve Number (SCS-CN) method is widely used according to USA landscape features classification, but not necessarily applicable to Romanian river basins characteristics. Our results show how the official Romanian rational methodology national standard (RNS) can be improved and the limits of SCS-CN method. [ABSTRACT FROM AUTHOR]