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1

The impact of water quality on the availability of phytoplankton and growth of Litopenaeus vannamei

Musa Muhammad, Thoyibah Auliarifka A., Puspitaningtyas Dyah A., Arsad Sulastri, Mahmudi Mohammad, Lusiana Evellin D., Maftuch Maftuch, Huda Agus S.

Journal of Water and Land Development

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2023

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no. 56

127--135

EN

This research analysed the availability of phytoplankton and the growth rate of Vannamei shrimp in relation to water quality changes. The research was carried out in February-March 2021 for a half cycle of shrimp cultivation in two ponds of the Brackish Water Fish Culture Probolinggo Laboratory in Probolinggo, East Java, Indonesia. The research used a descriptive method and included a survey. Sampling was made every two weeks for two months. Nine parameters were measured and ten shrimps were taken for a specific growth rate (SGR) measurement once per sampling. Data were analysed using the principal component analysis (PCA) and canonical correspondence analysis (CCA). Secondary data of water quality were added for the PCA. The results show that the phytoplankton found in the first pond consisted of Chlorophyta, Chrysophyta, and Cyanophyta, whereas the phytoplankton in the other pond included Chlorophyta, Chrysophyta, Cyanophyta, and Dinophyta. The abundance of phytoplankton ranged from 12-80∙103 cell∙cm-3, which indicated eutrophic waters. The PCA demonstrated that pH, nitrate, and total organic matter (TOM) significantly influenced phytoplankton abundance in the pond. In addition, water quality parameters, such as temperature, transparency, salinity, nitrite and phosphate levels, were tolerable in both ponds for the growth of shrimps. However, the level of pH was lower than the aquaculture quality standard, whereas those of nitrate, ammonia, and TOM were higher. The growth rate of Vannamei shrimp increased by 0.76–7.34%∙day-1.

2

Effect of water quality on the spatial distribution of charophytes in the Peshawar Valley, Khyber Pakhtunkhwa, Pakistan

Khuram Izaz, Ahmad Nadeem, Barinova Sophia

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 4

359--372

EN

The presented research was conducted in 2018–2019 in the Peshawar Valley, Pakistan, to study for the first time the effect of water quality on the spatial distribution of charophytes. A total of six taxa of charophytes were found at 41 sites in the Peshawar Valley along the banks of seven rivers, 16 streams and two wetlands: Chara braunii C.C.Gmelin, C. connivens Salzmann ex A.Braun, C. contraria A.Braun ex Kützing, C. globularis Thuiller, C. vulgaris Linnaeus, and Nitellopsis obtusa (Desvaux) J.Groves. Chara vulgaris was the most abundant species, followed by C. globularis, and C. contraria. Water pH, electrical conductivity (EC), total dissolved solids (TDS), salinity and dissolved oxygen (DO) were within the permissible limits for Pakistan, while water temperature, oxidation reduction potential (ORP) and resistivity showed deviations. Canonical Correspondence Analysis (CCA) revealed that DO affected Chara vulgaris, pH and resistivity affected C. braunii, C. connivens and C. globularis, temperature and ORP affected C. contraria and Nitellopsis obtusa. Furthermore, CCA showed that TDS, EC, and salinity had no effect on the spatial distribution of Chara contraria, C. vulgaris and Nitellopsis obtusa. Chara contraria and Nitellopsis obtusa should be protected under VU (Vulnerable) status (IUCN) along with their habitats.

3

Comparative Performance of Physicochemical and Diatom-Based Metrics in Assessing the Water Quality of Mert Stream, Turkey

Maraşlıoğlu Faruk, Bektaş Serdar, Özen Arda

Journal of Ecological Engineering

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2020

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Vol. 21, nr 8

18--31

EN

In this study, the authors aimed to compare the performance of the physicochemical-based water quality metrics (WQI, SWQMR) and diatom-based diatom metrics (TDI, BDI, GDI) to evaluate the water quality and ecological status of the Mert Stream. A total of 104 epilithic diatom species, belonging to 44 genera, were recorded during the study period. Navicula was the most dominant diatom in the sites near intensive farming areas, while Gomphonema was the most dominant species in the sites in vicinity of urban and industrial settlements. According to the water quality indices based on the physicochemical parameters and diatoms, the water quality in the upper and middle parts of the Mert stream was better than in the lower parts (higher amount of total suspended solids and higher conductivity). The structure of the epilithic diatom community was mostly shaped by total suspended solids, electrical conductivity and nutrients according to Canonical Correspondence Analysis results. The obtained results revealed that diatom metrics, especially GDI, and water quality metrics, especially WQI, can be used for the monitoring of lotic systems and provide useful complementary information on the ecological status of rivers in medium rainfall regions such as Samsun.

4

Steady state stability limit assessment when wind turbine penetrated to the systems using REI approach

Siswanto Agus, Suyuti Ansar, Chaerah Gunadin Indar, Mawar Said Sri

Przegląd Elektrotechniczny

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2019

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R. 95, nr 6

51--55

EN

High-powered wind turbines in the electric power system lead to a significant challenge in balancing production power and electrical power consumption caused by the winds intermittent. In this study, assessing the steady state stability limit (SSSL) in South Sulawesi system when wind turbines is penetrated the Sidrap bus using the REI-Dimo method. The method developed by Paul Dimo was later known as the Radial Equivalent Independent (REI)-Dimo to determine the stability of the system, the condition of the generator which is still stable when a disturbance or load changes occur. REI-Dimo serves to determine the Z equivalent to the generator so that a state of stability can be known. This study is conducted to determine the stability of the steady state generator in South Sulawesi system with 15 generators, 44 buses on the 150kV interconnection system. The simulation results show that the normal condition is 0.0323o, the Critical clearing angle is 111.903o, and the condition of the 100% loading of the critical clearing angle is 90.00o.

PL

W artykule założono limit stanu trwałej stabilności SSSL w systemie w prowincji South Sulawesi. Wykorzystano metodę zaproponowana przez Paula Dimo znaną jako Radial Equivalent Independent (REI)-Dimo do określania stabilności systemu kiedy warunki pracy generatora są stabilne przy zaklóconym odbiorze.

5

Finding Optimal Frequency and Spatial Filters Accompanying Blind Signal Separation of EEG Data for SSVEP-based BCI

Jukiewicz M., Buchwald M., Cysewska-Sobusiak A.

International Journal of Electronics and Telecommunications

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2018

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Vol. 64, No. 4

439--444

EN

Brain-computer interface (BCI) is a device which allows paralyzed people to navigate a robot, prosthesis or wheelchair using only their own brains reactions. By creating a direct communication pathway between the human brain and a machine, without muscles contractions or activity from within the peripheral nervous system, BCI makes mapping persons intentions onto directive signals possible. One of the most commonly utilized phenomena in BCI is steady-state visually evoked potentials (SSVEP). If subject focuses attention on the flashing stimulus (with specified frequency) presented on the computer screen, a signal of the same frequency will appear in his or hers visual cortex and from there it can be measured. When there is more than one stimulus on the screen (each flashing with a different frequency) then based on the outcomes of the signal analysis we can predict at which of these objects (e.g., rectangles) subject was/is looking at that particular moment. Proper preprocessing steps have taken place in order to obtain maximally accurate stimuli recognition (as the specific frequency). In the current article, we compared various preprocessing and processing methods for BCI purposes. Combinations of spatial and temporal filtration methods and the proceeding blind source separation (BSS) were evaluated in terms of the resulting decoding accuracy. Canonical-correlation analysis (CCA) to signals classification was used.

6

Advanced computational methods in component-oriented modelling of municipal solid waste incineration processes

Gaska K., Generowicz A.

Architecture Civil Engineering Environment

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2017

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Vol. 10, no. 1

117--130

EN

Poland was collected 9.6 million tonnes of municipal waste in 2012 (plus update). The primary method of dealing with municipal waste collected was organized depositing them in landfills. Mixed municipal waste accounted for almost 90% of all municipal waste collected (8.6 million tonnes). Poland is one of the lowest in the EU in terms of the use energy from waste. The analysis of complex real-time physical processes, thermal waste processing and determination of their optimal parameters requires a series of studies and detailed analysis of constituents of elementary processes (degassing, gasification, combustion). The apparent simplicity of process implementation often determines knowledge and practical experience required in their application. The relationships known and used in the design usually concern a homogeneous substance (conventional fuels) and do not correspond to the conditions and needs of processing of complex substances of a different chemical composition and physic-chemical properties. Due to the complexity of the real process, numerical calculations were carried out to simulate the operation of a waste incineration technology. For this purpose a mathematical model was developed as well as its implementation in the programming code of a high-level language. In order to calibrate and validate the model (compliance with the real process) calculations were performed on a specially prepared set of validation data. The authors analysed a group of processes that belong to one technology, looking into connections between degassing, gasification and combustion of carbonized substances in pure oxygen.

PL

W 2012 roku w Polsce zebrano 9.6 mln ton odpadów komunalnych. Podstawowym sposobem radzenia sobie z nimi było zorganizowane deponowanie na przygotowanych składowiskach. Zmieszane odpady komunalne stanowiły prawie 90% wszystkich zebranych odpadów komunalnych (8.6 mln ton). Polska jest jednym niewielu z krajów w UE, który praktycznie nie wykorzystanie energii z odpadów. Analiza złożonych w czasie rzeczywistym procesów fizycznych, przetwarzania termicznego przekształcania odpadów oraz ustalenie ich optymalnych parametrów wymaga szeregu badań i szczegółowej analizy składników procesów elementarnych (odgazowanie, zgazowanie, spalanie). Relacje znane i stosowane w modelowaniu dotyczą zwykle jednorodnej substancji (konwencjonalnych paliw) i nie spełniają warunków i potrzeb przetwarzania złożonych substancji o różnym składzie chemicznym i właściwościach fizyko-chemicznych, jakimi są odpady. Ze względu na złożoność rzeczywistego procesu obliczenia numeryczne zostały przeprowadzone w celu symulowania operacji technologii spalania odpadów. W tym celu został opracowany model matematyczny, jak i jego realizacja w kodzie programowania. W celu kalibracji i walidacji modelu obliczenia przeprowadzono na specjalnie przygotowanym zestawie danych walidacji.

7

Analiza symulacyjna wpływu poziomu wykrywania nośnej na wydajność sieci IEEE 802.11 o topologii linii

Ząbkowicz G., Natkaniec M.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2016

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nr 6

357--360, CD

PL

Artykuł zawiera analizę symulacyjną sieci standardu IEEE 802.11 w topologii linii ze stacjami ukrytymi ze zmiennym poziomem wykrywania nośnej. Praca nawiązuje do wersji draft standardu IEEE 802.11ax, w którym przewidziane jest użycie zmiennego poziomu wykrywania nośnej dla różnych stacji. W artykule przedstawiono wyniki symulacji ilustrujące wpływ zmiany poziomu wykrywania nośnej na wydajność całej sieci oraz ruch realizowany poszczególnych stacji. Analizowano również wpływ mechanizmu RTS/CTS na wydajność badanej sieci.

EN

This paper presents simulation analysis of IEEE 802.11 network with hidden nodes in line topology for different carrier sense levels. The work refers to the draft of the IEEE 802.11ax extension, which employs a dynamic carrier sense level mechanism. The article presents the simulations results of carrier sense level changes on network performance and throughput obtained by individual nodes. The impact of RTS/CTS mechanism on network performance was also analyzed.

8

Habitat Requirements of Marsh Dandelions (Taraxacum) in Polish and Estonian Coastal Grasslands

Bosiacka B., Kull T., Więcław H., Marciniuk P., Podlasiński M.

Polish Journal of Ecology

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2016

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Vol. 64, nr 2

213--230

EN

Factors determining the distribution of highly endangered marsh dandelion species in Polish and Estonian coastal grasslands have been investigated. The aim of this study was twofold: (i) to determine which environmental variables are responsible for the vegetation patterns in coastal grasslands with marsh dandelion and (ii) to analyse the ecological spectra of the identified marsh dandelion species. Altogether 51 plots were sampled (in 2013 and 2014). They were used following statistical analysis: DCA, CCA, Spearman's rank correlation test, Kruskal-Wallis test and hierarchical divisive cluster analysis (TWINSPAN). In total, three marsh dandelion species were found in Polish and Estonian coastal grasslands. The only species found in Poland was Taraxacum balticum. In Estonia all three species occur: T. balticum, T. decolorans and T. suecicum. Taraxacum balticum has been found in the widest ranges of all soil properties included, usually on organic, saline, non-carbonate and acid to slightly acid substrate. Taraxacum suecicum and T. decolorans have been found only on mineral, non-saline and slightly alkaline to alkaline substrate. The ecological spectra determined for endangered marsh dandelion species can be used to improve the methods of their protection. Nomenclature: mosses - Ochyra et al. (2003); vascular plants - Mirek et al. (2002).

9

Meeting reliability requirements for rotor ice protection system design

Golec P., Brzęczek J.

Diagnostyka

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2014

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Vol. 15, No. 1

31--35

EN

Increasing cost of rotorcraft maintenance forces transport companies to utilize their rotorcraft fleet to the fullest. This means that the most successful rotorcraft production company is the one that can provide rotorcraft that can operate in wider range of weather conditions than competition. Air transport authorities define requirements for both rotorcraft performance during flight in icing conditions and reliability of ice accretion protection systems. At the same time production company management requires that production, and development costs are as low as possible. This paper will focus on problems of meeting requirements of rotorcraft ice protection systems reliability using various types of reliability analyses that will help keep the system as simple and inexpensive as possible and are required in certification process of ice protection system.

PL

Ciągłe zwiększanie się kosztów utrzymania wiropłatów wymusza na firmach transportowych maksymalne wykorzystanie możliwości posiadanej floty. Oznacza to, że producent wiropłatów, aby osiągnąć sukces musi dostarczać produkt, który będzie w stanie operować w szerszym zakresie warunków pogodowych, niż firmy konkurencyjne. Organy nadzoru lotniczego określają zarówno wymagania dla własności lotnych wiropłatów w czasie lotu w warunkach oblodzenia oraz wymagania niezawodnościowe układu ochrony przed oblodzeniem. Jednocześnie zarządzający firmami produkującymi, wymagają, aby koszty produkcji i opracowania projektu były możliwie jak najniższe. Niniejsze opracowanie skupia się na problematyce sprostania wymaganiom niezawodnościowym przy wykorzystaniu różnych typów analiz niezawodnościowych, które pozwolą na zaprojektowanie możliwie najprostszych i najtańszych układów, i które są wymagane w procesie certyfikacyjnym układu ochrony wiropłata przed oblodzeniem.

10

Positive grass diversity-productivity relationships and controlling factors along an elevation gradient in Central Asian alpine grasslands

Li K., Fangmeier A., Hu Y., Lu C., Liu X.

Polish Journal of Ecology

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2012

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Vol. 60, nr 1

123-131

EN

The productivity-diversity relationship in grasslands is of great interest with regard to species loss in natural ecosystems, where species extinction is not random but directed. We carried out a three-year investigation from 2005 to 2007 along an elevation gradient in alpine grasslands of Central Asia in an area of 70 x 20 km2 at Bayinbuluk, Tianshan Mountains. We selected 9 sites (10 x10 m2) and 117 plots (1 x 1 m2) from 2460 to 3260 m a.s.l. with 100 m intervals of altitude. Species richness, productivity, soil characteristics, air temperature and relative humidity (May.August) were recorded. The relationship between plant diversity and productivity was significant and positive. We used ordination techniques such as Canonical Correspondence Analysis (CCA) to examine the relationship between vegetation and the environmental factors. The results showed that plant species composition, species richness and productivity were significantly affected by air temperature, soil pH and relative humidity across the study area.

11

Systemy rozpoznawania twarzy dla obrazów widzialnych i podczerwieni z wykorzystaniem CCA

Szaber M., Kamenskaya E.

Metody Informatyki Stosowanej

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2008

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nr 3 (Tom 16)

223--236

EN

Face recognition systems based on visual images have reached a significant level of maturity with some practical success. However, the performance of visual face recognition may degrade under poor illumination conditions and in completely darkness. Infrared images represent a viable alternative to visible images in the search for practical face recognition. In the article, we investigate the face recognition scheme where category of identified face images differs from that stored in face database. CCA (Canonical Correlation Analysis) method is used to build face recognition system with using visual and infrared images. Next, we considered three scenarios for this kind of system: during a day, at night and at dusk. We presented CCA method for this system that is proper for this tasks the schemes of scenario and examples of their working.

12

Co-variability of bars in a multi-bar nearshore zone determined with canonical correlation analysis (CCA)

Różyński G.

Archives of Hydro-Engineering and Environmental Mechanics

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2001

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Vol. 48, nr 2

91-106

EN

Nearshore bed variations of the southem Baltic shore were investigated with the aim of detecting co-variability among bed forms of a multi-bar system. The studied area is located at IBW PAN Coastal Research Station at Lubiatowo. The beach consists of fine sand of median grain equal to 0.22 mm, is mildly sloping and boasts multiple (usually 4) bars, which is typical for the coast in the southem Baltic. Data on bed topography were collected along 27 lines, equally spanned every 100 m, since 1987 to 1999, usually twice a year. Fairly high alongshore bed homogeneity made it possible to choose one representative profile for which the CCA method was employed. The method demonstrated considerable potential for detecting co-variability of bed features in the nearshore zone. The results show that some 80% of variability in the region of the offshore slope of the outermost bar can be attributed to variations of Dean equilibrium profiles. The portion of variability of the two innermost bars due to variations of equilibrium profiles equals 40%. Horizontal counter-movements of outer and inner bars can be responsible for same 20%. The remaining 40% should be related to highly variable short time scale phenomena like breakers and wave driven currents in the vicinity of inner bars.