Wyniki wyszukiwania - BazTech

1

Determination of groundwater recharge-discharge zone to support water resources in Galur-Lendah area, Indonesia

Listyani R. A. T., Prabowo Ignatius A., Suparta Wayan

Journal of Water and Land Development

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2023

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no. 56

203--214

EN

The impact of changes in regional development along with the construction of Yogyakarta International Airport in Kulon Progo Regency may affect land use changes as the activities of the surrounding population. Galur-Lendah area, which is located near the city of Yogyakarta and acts as the entrance to Kulon Progo, will also develop. Along with these developments, the determination of the groundwater recharge-discharge area is needed to ensure the availability of groundwater at this site. The purpose of this study was to determine the zonation of groundwater recharge-discharge areas to support the availability of groundwater. The method of research is a spatial analysis using a geographic information system (GIS) based on ratings and weighting values for six parameters, including slope, rainfall, groundwater table depth, soil type, rock permeability, and land use. The field hydrogeological was also conducted to find out rock permeability and groundwater quality (pH, EC, TDS). The results showed that areas with potential for groundwater recharge were in the central and northeastern parts of the study area and the discharge zones in the north and south were with potential infiltration values of 26-43 and 44-59, respectively. However, the recharge area can still function as a discharge zone.

2

Impact of suction space leaks on the discharge pressure pulsation of positive displacement pump

Rabsztyn Dominik, Klarecki Klaudiusz

Journal of KONBiN

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2023

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Vol. 53, iss. 2

131--140

EN

This paper presents the results of the experiments related to measuring the impact of the suction space leaks in the gear pump on the pressure pulsation, resulting in the aeration of hydraulic fluid. The research authors claim that it is possible to detect leaks in the suction line, causing aeration of the hydraulic fluid, by recording and analyzing the pressure pulsation in the positive displacement pump discharge line. The measurements were performed for six leakage values, five discharge pressure settings and under constant hydraulic fluid temperature. The obtained results were analyzed in the time and frequency domains. The results of experimental research confirmed the author’s thesis.

PL

W artykule przedstawiono wyniki badań eksperymentalnych związanych z pomiarem wpływu nieszczelności przestrzeni ssącej na zmianę przebiegu pulsacji ciśnienia pompy wyporowej, spowodowane zapowietrzeniem cieczy hydraulicznej. Autorzy badań twierdzą, że istnieje możliwość wykrycia nieszczelności przewodu ssawnego, powodującego aerację cieczy hydraulicznej przez rejestrację, a następnie analizę przebiegu pulsacji ciśnienia w linii tłocznej pompy wyporowej. Eksperyment przeprowadzono dla sześciu wartości nieszczelności oraz pięciu nastaw ciśnienia tłoczenia przy stałej wartości temperatury cieczy hydraulicznej. Zarejestrowane wyniki badań przeanalizowano w domenie czasu oraz częstotliwości. Wyniki badań eksperymentalnych potwierdziły postawioną przez autorów tezę.

3

A new “Emir” composite for the decolmatage of oil and gas layers after drilling and during deposit exploitation to increase the efficiency of hydrocarbon production

Hubych Ihor, Krupskyi Yurii, Pavlyn Mykola, Viitenko Vasyl, Feichuk Vitalii

Journal of Geotechnology and Energy

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2022

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Vol. 39, no. 2

5--13

EN

A new effective composite “Emir” has been created, which reduces the swelling of clay minerals and cleans the near-well zone of oil and gas-saturated layers from residues of drilling fluid, technical and formational water, resin-asphaltene components and paraffin; thereby restoring the efficiency of the well. The composite has high cleaning characteristics and the ability to foam in the presence of highly mineralized waters (up to 250 g/l), oil products and mineral acids. It also forms both straight and reverse mobile water-oil emulsions, which is important for cleaning oil layers. Based on the results of testing the “Emir” composite in production conditions on gas and oil wells, it was concluded that the use of “Emir” allows the discharge of hydrocarbon fluids to increase from 20% to 50% or more. The “Emir” composite can also be used on “low-flow” wells which have been clogged or eliminated for geological and technical reasons; this makes it possible to significantly increase the recoverable reserves of hydrocarbons in various oil and gas-bearing regions, especially taking into account the small volumes of drilling and the low success rate of searching for new oil and gas fields.

4

Analysis of the Chlorophyll and Carotenoids Content in Brassica Chinensis Plants Using IoT-Based Sprinkle Irrigation

Noerhayati Eko, Mustika Soraya Norma, Mardiyani Siti Asmaniyah, Ingsih Ita Suhermin, Afroni Muhammad Yasa

Journal of Ecological Engineering

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2022

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Vol. 23, nr 9

25--33

EN

The agricultural sector is currently witnessing the use of Internet of Things (IoT) to drive significant innovations across key interests, particularly irrigation. A sprinkler designed with an Arduino controller was developed in this study. The device is among the fastest growing agricultural irrigation systems. The plant studied is Brassica Chinensis, because this vegetable is one of the most commonly consumed vegetables by Indonesian people. However, emphasis is also placed on plant quality as an important consideration, not only on the device’s operational performance. The purpose of this research was to compare the plant quality, including the dissolved solids, chlorophyll, carotenoid, and vitamin C using manual and Arduino-based sprinkler. As consequence, three treatment methods were employed, termed: the use of manual sprinkle, e.g. P0, and Arduino-based IoT sprinkler, described as P1 and P2. Under these conditions, the chlorophyll quality was comparable to the results obtained using the manual application. P1 is a situation where the sprinkler is manually set by the farmer via the app. Meanwhile, P2 uses a sprinkler which is automatically regulated by the system. Under these conditions, the chlorophyll quality generated with the IoT sprinkler was comparable to the results obtained using the manual application.

5

Adapting the Methods for Assessing a Water Quality when Normalizing the Pollutant Discharges in Ukraine to the Regulatory Requirements of the European Union

Yurasov Sergey, Safranov Tamerlan, Chugai Angelina, Kuryanova Svetlana, Artvykh Julia

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 3

167--176

EN

The article presents general positions and features of a water quality assessment according to the norms of the European Union (EU), shows their difference from the national (Ukrainian) standards. It is proposed to improve the Ukrainian standards for assessing a water quality in accordance with the EU standards. On the example of the Danube and the Dniester rivers, a chronological variability of the water quality indicators is considered, the time trends of the indicators are approximated and the parameters of their distribution laws are determined. The following dependences are established: when approximating the distribution of the indicators it is better to use the lognormal law; an indicators time trend is reflected more accurately by the exponential dependence; a lognormal distribution of a trend-normalized indicator can be formally considered as one-parameter (one of the parameters – an average value of the logarithms of the normalized series – is zero). It is shown that for the previous period of time and in the future when normalizing the discharges of pollutants together with wastewater, a water quality assessment in the control points of the water bodies will meet the requirements of the EU standards on a frequency of exceeding the maximum permissible concentrations with the security which is equal to 5 or 10% depending on the purpose of the water body (5% – for fishery facilities, 10% – for drinking and recreational water use facilities).

6

Efficiency of energy storage control in the electric transport systems

Sablin Oleg, Bosyi Dmytro, Kuznetsov Valeriy, Lewczuk Konrad, Kebal Ivan, Myamlin Sergiy S.

Archives of Transport

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2022

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Vol. 62, iss. 2

105--122

EN

The problems of storage and supplying the energy, together with reducing energy intensity for transport, are now crucial for developing sustainable and reliable transport systems. The energy network must be gradually adapted to new loads and power consumption patterns, especially in railways. The article aims to develop the simulation model to investigate the energy storage systems in its use in the electric transport infrastructure. The authors review selected technical solutions for electric energy storage in transport. The theoretical aspects of energy exchange in the energy storage systems were presented as a base for a continuous simulation model of electric transport power supply. In the non-periodic random voltage input applied to the storage unit, it is proposed to use the calculation method based on the Duamel integral to analyze its charge-discharge processes. The resistance functions were applied to analyze the traction power supply mode with variable in time and space by active loads. The simulation showed that the direct connection of the unit to the traction network significantly reduces the traction energy consumption.

7

Modelling erosion and sedimentation in a small watershed, East Java, Indonesia

Sujarwo Mohamad Wawan, Indarto Indarto, Mandala Marga

Journal of Water and Land Development

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2021

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no. 50

265--273

EN

Changes in land use as a result of human activities may generate the alteration of hydrometeorological disasters. Erosion, sedimentation, floods and landslides frequently occur in the Sanenrejo watershed (±292 km2), located in East Java, Indonesia. In this paper, the soil and water assessment tool (SWAT) model is used to evaluate the hydrological processes in this small watershed. The digital elevation model (DEM) is used as the primary input for deriving the topographic and physical properties of the watershed. Other input data used for the modelling processes include soil type, land use, observed discharge data and climate variables. These data are integrated into the SWAT to calculate discharge, erosion and sedimentation processes. The existing observed discharge data used to calibrate the SWAT output at the watershed outlet. The calibration results produce Nash–Sutcliffe efficiency (NSE) of 0.62 and determination coefficient (R2) of 0.75, then the validation result of 0.5 (NSE) and 0.63 (R2). The middle area faced the highest erosion and sedimentation that potentially contribute to hydrometeorological disasters.

8

Discharge of a Triangular Orifice under Free Flow Conditions

Sosnowska Anna

Archives of Hydro-Engineering and Environmental Mechanics

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2021

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Vol. 68, nr 1

19--28

EN

In this paper, flow through a free triangular orifice is considered. The comparison of two formulas was conducted for discharge calculations: a large orifice formula and a small orifice formula. The results show that, above a certain value of upstream head to orifice height ratio there is no need for small-large formula discrimination. The differences in the outcomes for the two formulas are negligible for upstream head to orifice height ratios greater than 3. This means that a small orifice formula can be used instead of a large orifice formula. Calculations were performed for different variants of triangle orientation (with tip downwards, sidewards and upwards) as well as for different dimensions of orifice (equilateral and isosceles). The calculations also included different submergence levels of the upper edge of the orifice and variable dimensions of the orifice with constant upstream head. Neither of these conditions affect the relative deviation values for small and large orifice formulas.

9

Effect of Land Use Changes of Upstream Komering Sub Watershed on Declining Water Availability

Yuono Agus Lestari, Putranto Dinar Dwi Anugerah, Tukirun Sarino

Journal of Ecological Engineering

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2020

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Vol. 21, nr 2

126--130

EN

Potential water resources in the upstream part of the Komering sub-watershed, in March each year ranges from 645.49 m3/sec. With a debit of that size, it should be able to increase national agricultural production in South Sumatra, Indonesia. However, in August – September, the discharge of water availability in the upstream part of the Komering sub-watershed decreased to only 43.08 m3/sec. To analyze the reduced mainstay discharge of the Upstream Komering sub-watershed, due to poor land use practices in the upstream area and the effects of climate variability, it can be analyzed by analyzing land cover conditions, the value of rain variability, and the magnitude of evapotranspiration and validation of direct measurement of river discharge in the field. Changes in land use for the upstream part of the Komering sub-watershed, which are used mostly by residents as community plantation areas, have increased the critical condition of the upstream Komering sub-watershed area of 2,517,560 Km2, or about 65.66% of the total upstream Komering sub-watershed. From the measurement of debit data at the Perjaya Dam in the last fifteen years (2005–2019), the largest main discharge value in 2 weeks to two months in April was 241.67 m3/sec, while the smallest mainstay discharge occurred in the first 2 weeks of October at 54.69 m3/sec. A large difference between the largest and smallest mainstay discharge, it is necessary to think of a way so that the availability of water is always maintained throughout the year (the difference between the mainstay discharge between the rainy season and the dry season so that it is not so extreme). Some ways that can be done to maintain the availability of water include making a reservoir that can be used during the dry season, or increasing storage in the soil by reforestation and harvesting rain.

10

The Use of a Standardized Runoff Indicator for Hydrological Characterization of Selected Rivers of Poland and Slovakia

Kubiak-Wojcicka Katarzyna, Zeleňáková Martina, Purcz Pavol, Simovova Dorota

Rocznik Ochrona Środowiska

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2019

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Tom 21, cz. 1

167--183

EN

This study compares river discharge of two catchments in Central Europe. The catchments' areas are similar while their geological structure differs significantly. The River Laborec (Slovakia) is an example of a mountain river, draining hardly permeable land. The River Gwda (Poland) is a lowland river, draining mainly sandy formations. The study used average monthly flows in the period of 1980-2010 measured on water gauges Humenne and Izkovce on the river Laborec and water gauges Piła and Ptusza on the river Gwda. The aim of the study is a review of hydrological drought course in two catchments that differ in their structure. The analysis was conducted on the basis of the SRI (Standardized Runoff Index), which was calculated in various time scales, i.e. 1, 3, 6, 9 and 12 months. It is a dimensionless index, which allows determination and comparison of dry and wet periods for rivers in various regions. The analysis of duration and intensity of the SRI in short time periods revealed that hydrological droughts on the river Gwda lasted longer and were less intense than in case of river Laborec. The duration of the wet periods (SRI > 1.0) was similar on both rivers, however the phenomenon intensity was higher on the mountain river. The analysis of longer accumulation periods revealed that on the river Gwda wet periods got longer, while hydrological drought periods were shortened. In case of the river Laborec, wet periods were slightly shortened, while drought periods have extended significantly.

PL

W niniejszym opracowaniu porównano odpływ rzeczny w 2 zlewniach centralnej Europy o podobnej powierzchni zlewni i zróżnicowanej budowie geologicznej. Rzeka Laborec (Słowacja) jest przykładem rzeki górskiej, odwadniającej tereny trudno przepuszczalne, natomiast rzeka Gwda (Polska) reprezentuje zlewnie pojezierną, zbudowaną głównie z utworów piaszczystych. W opracowaniu wykorzystano średnie miesięczne wartości przepływów w okresie 1980-2010 na posterunkach wodowskazowych Humenne i Izkovce na rzece Laborec oraz Piła i Ptusza na rzece Gwdzie. Celem niniejszego opracowania jest ocena przebiegu suszy hydrologicznej w dwóch zlewniach o zróżnicowanej budowie. Analizę przeprowadzono w oparciu o wskaźnik SRI (Standardized Runoff Index), który obliczono w różnych skalach czasowych tj. 1, 3, 6, 9 i 12 miesięcy. Jest to bezwymiarowy wskaźnik, który umożliwia wyznaczenie i porównanie okresów suchych i mokrych dla rzek z różnych regionów. Analiza czasu trwania i intensywności wskaźnika SRI w krótkich skalach czasowych wykazała, że susze hydrologiczne (SRI < -1.0) na rzece Gwdzie trwały dłużej i charakteryzowały się mniejszą intensywnością niż w przypadku rzeki Laborec. Czas trwania okresów wilgotnych (SRI > 1.0) był podobny w obu rzekach, jednak większą intensywność zjawiska notowano w rzece górskiej. Analiza dłuższych okresów kumulowania wykazała, że dla Gwdy okresy wilgotne uległy wydłużeniu, natomiast skróceniu uległy okresy suszy hydrologicznej. W przypadku rzeki Laborec okresy wilgotne uległy niewielkiemu skróceniu, natomiast okresy suszy zdecydowanie uległy wydłużeniu.

11

Reżim opadów i przepływów w zlewni rzeki Zagożdżonki po profile Płachty Stare i Czarna

Hejduk A., Kaznowska E., Hejduk L., Gładecki J.

Woda-Środowisko-Obszary Wiejskie

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2018

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T. 18, z. 1

37--55

PL

Celem pracy jest ocena reżimu opadów i przepływów w okresie 2011–2015 na tle lat 1963–2015 (opady) i 1991–2015 (przepływy) w zlewni rzeki Zagożdżonki po profile Płachty Stare i Czarna. Okres badawczy obejmuje realizację w wyżej wymienionej zlewni dwóch projektów badawczych finansowanych przez Narodowe Centrum Nauki dotyczących wezbrań zimowych i niżówek. Charakterystyki opadów dokonano na podstawie analizy sum dobowych, miesięcznych, półrocznych i rocznych. Do oceny zmienności sum opadów miesięcznych i rocznych zastosowano kryterium KACZOROWSKIEJ [1962]. Wartości przepływów dobowych z wielolecia, odnotowanych w profilach pomiarowych Płachty Stare (1963–2015) i Czarna (1991–2015) stanowiły podstawę charakterystyki hydrologicznej. Stosując kryterium hydrologiczne zaproponowane przez OZGĘ-ZIELIŃSKĄ [1990], na hydrogramach przepływów wyodrębniono niżówki i wezbrania. Za dolną granicę wezbrania przyjęto przepływ NWQ (najniższy z maksymalnych przepływów rocznych), zaś za granicę niżówek przyjęto przepływ SNQ (średni z najniższych przepływów rocznych). Charakterystyki hydrologiczne lat 2011– 2015 odniesiono do wielolecia 1963–2015.

EN

The aim of the study was to evaluate precipitation and hydrological conditions in the period 2011–2015 against the background of long term data collected in the Zagożdżonka River catchment. Precipitation characteristics are based on the analysis of daily, monthly, semi-annual and annual totals. The criterion presented by KACZOROWSKA [1962] was used to evaluate the variability of monthly and yearly precipitation totals. Hydrological characteristic was based on daily flows data recorded in Płachty Stare (1963–2015) and Czarna (1992–2015) gauging station. Two extreme phenomena as flood and drought were identified using daily hydrograph. The threshold of SNQ (mean of the lowest annual flows) was used for flood identification, as well as the threshold of NWQ flow (the lowest of the highest annual flows) was used to identify droughts.

12

Zagrożenia od wyładowań z powierzchni tkanin

Kacprzyk R., Król J.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 10

113--117

PL

Zaproponowano uproszczony model układu uziemiony obiekt-naładowana tkanina, pozwalający na oszacowanie energii możliwej do uwolnienia z powierzchni tkaniny podczas wyładowania elektrostatycznego. Badano tkaninę syntetyczną zawierającą włókna przewodzące. Jako uziemiony obiekt przyjęto elektrodę kulistą, stosowaną w pomiarach ładunku przenoszonego. Przedstawiony model prowadzi do potęgowej zależności energii uwolnionej w trakcie wyładowania od gęstości wprowadzenia włókien przewodzących.

EN

A simplified model of the grounded object-charged fabric system was proposed. It allows to estimate the energy that can be released from the fabric surface during electrostatic discharge. The synthetic fabric containing conductive fibres was tested. A spherical electrode, used for charge transport measurements, was adopted as a grounded object. The presented model has led to the power type relation between released energy and the density of introducing conductive fibres.

13

Electrochemical characteristics of LaNi4,5Co0,5 alloy composite hydrogen storage material at high discharge rates

Stefaniak A., Bordolińska K., Bala H.

Ochrona przed Korozją

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2018

|

nr 4

90--92

EN

Electrochemical hydrogen storage behavior of LaNi4,5Co0,5 powder composite electrode cycled in 6M KOH solution at increased discharge rates is discussed. Galvanostatic charging/discharging technique has been applied to determine high rate discharge ability (HRD) after N = 15 and N = 60 cycles. The anodic plots for both tested options are typical: electrode potential nearly linearly (with very low slope) increases with electrode discharge and then sharply jumps towards Eend = –0.5V (HgO/Hg) after electrode full dehydrogenation. Maximum discharge capacity (298 mAh·g–1 at –0.5C/+0.5C i.e. –186/+186 mA·g−1 ) has been achieved after N = 31 cycles. The HRD markedly decreases with electrode cycling. After 15 cycles the HRD falls to 46.8 % at discharge rate of 5C. The SEM examinations reveal severe structural deterioration of the electrode, especially evident after 60 cycles at the greatest discharge rates.

PL

Dyskutowane jest elektrochemiczne zachowanie cyklowanego stopu wodorochłonnego LaNi4,5Co0,5 w środowisku 6M KOH, przy wzrastających szybkościach rozładowania. Dla wyznaczenia zdolności do rozładowywania przy wysokich prądach anodowych (HRD), zastosowano technikę galwanostatycznych krzywych ładowania/rozładowania. Zmiany HRD mierzono po N = 15 i N = 60 cyklach. Proces anodowego rozładowania dla dwu wymienionych opcji wykazywał typowe przebiegi: potencjał elektrodowy nieznacznie wzrasta, po czym, po całkowitym utlenieniu wodoru, obserwuje się jego gwałtowny skok do wartości Eend = –0,5V (HgO/Hg). Maksymalną pojemność rozładowania (298 mAh·g–1 przy –0,5C/+0,5C, tj. –186/+186 mA·g−1 ) elektroda osiąga po N = 31 cyklach. Parametr HRD wyraźnie maleje wskutek cyklowania. Po 15 cyklach HRD osiąga poziom 46,8% dla szybkości rozładowania równej 5C. Obserwacje SEM ujawniają silną destrukcję strukturalną elektrody, szczególnie ewidentną dla 60 cykli przy największych szybkościach rozładowania.

14

Model of water economic value optimization based on the land use change

Satyagraha B., Limantara L. M., Bisri M., Andawayanti U.

Journal of Water and Land Development

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2018

|

no. 36

143--152

EN

Land use change in the upstream of Rawa Pening watershed which is more and more dominated by residence and industry causes the increasing of surface flow discharge on the rainy season. In addition, the decreasing of Rawa Pening ability in storing flood discharge also influences to the cropping area in surrounded Rawa Pening. Water surpluses occurring downstream are related to the land use change in the upstream which gives impact in the downstream. However, it is as an important reason to carry out the optimization of water economic value in this region. The disruption of water availability causes the decreasing of any production like hydroelectrical power, fresh water, and rice production, so the optimal water economy is decreasing. This research intends to: 1) analyse the effect of land use change to the water availability; 2) analyse the land use change to the water balance; and 3) build and analyse the optimization model of water economic value due to the land use change. Results show that there is the different influence of land use change during the years to the results of water value optimization.

PL

Zmiana użytkowania ziemi w górnej zlewni Rawa Pening coraz bardziej zdominowanej przez zabudowę mieszkalną i przemysłową powoduje wzrost odpływu powierzchniowego w porze deszczowej. Malejąca zdolność Rawa Pening do retencji wód powodziowych wpływa na okoliczne tereny uprawne. Nadmiary wody występujące w dolnej części zlewni są powiązane ze zmianami użytkowania ziemi w górnej części zlewni. Ta zależność jest ważnym powodem podjęcia optymalizacji gospodarki wodnej regionu. Zakłócenia w dostępności wody powodują zmniejszenie produkcji energii elektrycznej wytwarzanej w hydroelektrowniach, wody słodkiej i ryżu, skutkiem czego maleje optymalne wykorzystanie wody. Badania miały na celu: 1) analizę wpływu zmian użytkowania ziemi na dostępność wody; 2) analizę wpływu tych zmian na bilans wodny; 3) skonstruowanie i analizę modelu optymalizacji gospodarczej wartości wody w związku ze zmianami użytkowania ziemi. Wyniki dowodzą różnego wpływu zmian w czasie na optymalizację wartości wody.

15

Zmiany wydajności źródeł, jako reakcja na okresowy niedobór opadów

Kubicz J., Sygidus K.

Inżynieria Ekologiczna

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2018

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Vol. 19, nr 6

26--32

PL

Według prowadzonych badań na skutek zmian klimatycznych, następuje zwiększanie się ilości obszarów dotkniętych suszą oraz wydłużanie się okresów suszy przy jednoczesnym wzroście jej intensywności. Skutkiem suszy jest niedostateczne tempo odnawiania zasobów wód podziemnych, a konsekwencją tego zjawiska jest zmniejszenie dopływu wody do źródeł i spadek i ich wydajności. Aby możliwa była ocena skutków zmian klimatu, w kontekście dostępności zasobów wodnych, konieczne jest zbadanie i opisanie zależności między czynnikami meteorologicznymi a warunkami hydrologicznymi. Dlatego w niniejszej pracy podjęto próbę opisania relacji między wydajnością źródeł w południowo-zachodniej Polsce a niedoborem opadów. Obliczono współczynniki korelacji między wydajnością źródeł a wskaźnikiem SPI w różnych skalach czasowych. Najwyższy poziom reakcji stwierdzono w przypadku wydajności i niedoborów opadów o okresie kumulowania 6 miesięcy (SPI-6).

EN

As a result of climate change there is an increase in the number of the areas affected by drought and intensity of the drought. The effect of the drought is the insufficient rate of renewing groundwater resources. The consequence of this phenomenon is reduction groundwater inflow and decrease discharge of springs. Assess the effects of climate change, in the context of the availability of groundwater resources, it is necessary to describe the relationship between meteorological and hydrological conditions. This paper describe the relations between discharge of the springs in south-western Poland and periodic precipitation deficit. There were calculated correlation coefficients between discharge and SPI index in different time scales. The highest level of the reaction was found between and precipitation deficit in 6-month accumulation period (SPI-6).

16

Applicability of TOPMODEL in the Mountainous Catchments in the Upper Nysa Kłodzka River Basin (SW Poland)

Jeziorska J., Niedzielski T.

Acta Geophysica

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2018

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Vol. 66, no. 2

203--222

EN

River basins located in the Central Sudetes (SW Poland) demonstrate a high vulnerability to flooding. Four mountainous basins and the corresponding outlets have been chosen for modeling the streamflow dynamics using TOPMODEL, a physically based semi-distributed topohydrological model. The model has been calibrated using the Monte Carlo approach—with discharge, rainfall, and evapotranspiration data used to estimate the parameters. The overall performance of the model was judged by interpreting the efficiency measures. TOPMODEL was able to reproduce the main pattern of the hydrograph with acceptable accuracy for two of the investigated catchments. However, it failed to simulate the hydrological response in the remaining two catchments. The best performing data set obtained Nash-Sutcliffe efficiency of 0.78. This data set was chosen to conduct a detailed analysis aiming to estimate the optimal timespan of input data for which TOPMODEL performs best. The best fit was attained for the half-year time span. The model was validated and found to reveal good skills.

17

Przestrzenne związki pomiędzy rozmieszczeniem najwydajniejszych źródeł a neotektoniką w zlewni Białej Łady na Roztoczu Gorajskim (środkowo-wschodnia Polska)

Chabudziński Ł., Brzezińska-Wójcik T.

Przegląd Geologiczny

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2017

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Vol. 65, nr 11/2

1184--1188

EN

Considerations of the relationships between the groundwater systems and neotectonics in the Roztocze region have been first undertaken by J. Malinowski in the 1970s. Until now, no research results have supported or challenged the hypothesis proposed by this author. Therefore, this paper is an attempt to present the results of a detailed analysis of the relationships between the distribution of springs characterised by the highest discharge rates and neotectonics. The study area covered the Roztocze part of the Biała Łada catchment, which has been subjected to detailed hydrogeological and hydrological investigations since the 1960s. The study was based on spatial data concerning the distribution of springs and information about the discharge rates of the largest springs. The data were juxtaposed with the relatively active tectonic zones distinguished in the catchment based on the relative tectonic activity index (Iat). The index was calculated using ArcGIS software, based on DEM, and with the use of the ArcNEO tool. The investigations indicated that springs with the highest discharge rates are located in the intersection zone of the main Biała Łada dislocation with accompanying faults. Additionally, the springs are located in the mouth sections of dry, asymmetric valleys and at the foot of their steep slopes following isostatically elevated hanging walls. The results support the hypothesis put forward by J. Malinowski (1993), who suggested that the distribution of springs with the highest discharge rates is determined by tectonics of the rock massif, in particular the distribution of the main dislocations and the accompanying subordinate discontinuous tectonic structures.

18

Effect of surface modification of the LaNi4.5Co0.5 powder with thin silicon film on the electrochemical performance of composite hydride electrode

Bordolińska K., Bala H.

Ochrona przed Korozją

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2017

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nr 4

102--104

EN

Surface of LaNi4.5Co0.5 hydride alloy powder has been modified by magnetron sputtering using silicon target. The process of composite electrodes cycling at −0.5 C/+0.5 C charge/discharge rates has been carried out in 6 M KOH throughout 40 cycles at ambient temperature. Deposition of thin Si films on the active powder improves its hydrogenation kinetics: the exchange current densities of H2O/H2 system are 5÷10% greater on the modified electrode. After some initial cycles, logarithm of discharge capacity linearly decreases with the number of cycles. For powders modified with silicon films, the slope of rectilinear segment of log Qdisch = f(N) relationship is 2.5 times lower than that for unmodified powder. The presence of Si film evidently decreases the electrode corrosion rate and prolongs the electrode half decay cycle number.

PL

Powierzchnię sproszkowanego stopu wodorochłonnego LaNi4.5Co0.5 modyfikowano poprzez rozpylanie jonowe z użyciem targetu krzemowego. Proces cyklowania kompozytowych elektrod przeprowadzono z szybkościami −0.5 C/+0.5 C w 6M roztworze KOH w temperaturze otoczeniadla 40 cykli ładowania/rozładowania. Warstwy napylone poprawiają kinetykę elektrosorpcji wodoru przez proszek aktywny, gdyż w ich obecności gęstość prądu wymiany układu H2O/H2 wzrasta o 5÷10%. Po kilku początkowych cyklach logarytm pojemności rozładowania elektrod liniowo maleje z liczbą cykli. Dla proszków modyfikowanych warstwą krzemu, nachylenia liniowych odcinków zależności log Qdisch = f(N) są 2,5 raza mniejsze niż dla proszku wyjściowego. Obecność filmu Si wyraźnie zmniejsza szybkość korozji elektrody i wydłuża cykl połówkowy jej degradacji korozyjnej.

19

Using artificial neural network (ANN) for prediction of sediment loads, application to the Mellah catchment, northeast Algeria

Bouzeria H., Ghenim A. N., Khanchoul K.

Journal of Water and Land Development

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2017

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no. 33

47--55

EN

In this study, we present the performances of the best training algorithm in Multilayer Perceptron (MLP) neural networks for prediction of suspended sediment discharges in Mellah catchment. Time series data of daily suspended sediment discharge and water discharge from the gauging station of Bouchegouf were used for training and testing the networks. A number of statistical parameters, i.e. root mean square error (RMSE), mean absolute error (MAE), coefficient of efficiency (CE) and coefficient of determination (R2) were used for performance evaluation of the model. The model produced satisfactory results and showed a very good agreement between the predicted and observed data. The results also showed that the performance of the MLP model was capable to capture the exact pattern of the sediment discharge data in the Mellah catchment.

PL

W niniejszej pracy przedstawiono działanie najlepszego algorytmu sieci neuronowych z użyciem wielowarstwowego perceptronu do przewidywania odpływu zawiesiny ze zlewni rzeki Mellah. Do treningu i testowania sieci użyto serii czasowych dobowego odpływu zawiesiny i odpływu wody z profilu wodowskazowego Bouchegouf. Do oceny działania modelu wykorzystano szereg parametrów statystycznych, takich jak pierwiastek ze średniego błędu kwadratowego, średni błąd bezwzględny, współczynnik wydajności i współczynnik determinacji. Model dawał zadowalające wyniki i wykazywał bardzo dobrą zgodność między obserwowanymi i przewidywanymi danymi. Wyniki świadczą także, że model jest w stanie wychwycić szczegółowy wzorzec odpływu zawiesiny ze zlewni rzeki Mellah.

20

Changes in seasonal streamflow extremes experienced in rivers of Northwestern South America (Colombia)

Pierini J.O., Restrepo J.C., Aguirre J., Bustamante A.M., Velásquez G.J.

Acta Geophysica

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2017

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Vol. 65, no. 2

377--394

EN

A measure of the variability in seasonal extreme streamflow was estimated for the Colombian Caribbean coast, using monthly time series of freshwater discharge from ten watersheds. The aim was to detect modifications in the streamflow monthly distribution, seasonal trends, variance and extreme monthly values. A 20-year length time moving window, with 1-year successive shiftments, was applied to the monthly series to analyze the seasonal variability of streamflow. The seasonal-windowed data were statistically fitted through the Gamma distribution function. Scale and shape parameters were computed using the Maximum Likelihood Estimation (MLE) and the bootstrap method for 1000 resample. A trend analysis was performed for each windowed-serie, allowing to detect the window of maximum absolute values for trends. Significant temporal shifts in seasonal streamflow distribution and quantiles (QT), were obtained for different frequencies. Wet and dry extremes periods increased significantly in the last decades. Such increase did not occur simultaneously through the region. Some locations exhibited continuous increases only at minimum QT.