Wyniki wyszukiwania - BazTech

1

Distribution of Microplastics in Domestic Wastewater and Microplastics Removal Potential in Wastewater Treatment Plants

Fauzi Mhd., Darnas Yeggi, Muna Cut Rauzatun, Nizar Muhammad

Journal of Ecological Engineering

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2023

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Vol. 24, nr 12

79--86

EN

Microplastics in domestic wastewater are detrimental to living organisms and appear in a variety of sizes, colors, and shapes. The purpose of this study is to examine the distribution of microplastics in domestic wastewater, as well as the possibility for microplastic removal in wastewater treatment plants (WWTP). The sampling method used is SNI 6989.59:2008 concerning Wastewater Sampling Methods that Apply in Indonesia. To remove organic compounds in the sample, 0.05 M Fe (II) and 30% H2O2 solution were added by the digestion process at 75 °C for 30 minutes and cooled. Samples were filtered using Whattman GF/C filter paper with the help of a vacuum pump and dried. To identify the concentration, shape, size, color of microplastics, visual analysis was used with the help of a microscope using the zig-zag technique. The concentration of microplastics in domestic wastewater in Gampong Garot is 30.17 ± 0.75 particles/100 mL sample. The most commonly found microplastic size is 1,001–5,000 μm, while the dominant color is transparent. The forms of microplastic found in the samples were fiber, fragments and microbeads with a percentage of 65.20%, 23.16% and 11.64%, respectively. These microplastics come from local community activities such as washing clothes, bathing, washing dishes, and other activities. So, it is necessary to treat domestic wastewater using WWTP. Not only does it remove organic matter and nutrients, WWTP also has the potential of microplastics removal around 7–99% depending on the processing unit.

2

On the quasi-efficient frontier of the set of optimal portfolios under hybrid uncertainty with short sales allowed

Rogonov Stepan A., Soldatenko Ilia S., Yazenin Alexander V.

Control and Cybernetics

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2022

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Vol. 51, No. 4

445--466

EN

The paper describes the methods for constructing a quasi-efficient frontier of minimum risk portfolio under conditions of hybrid uncertainty with allowed short sales. Investor’s acceptable level of expected return is defined in crisp and fuzzy forms. Obtained results are illustrated on a model example. The dependence of the quasi-efficient frontier on the value of α-level is investigated.

3

Model of a minimal risk portfolio under hybrid uncertainty

Yazenin Alexander V., Soldatenko Ilia S.

Control and Cybernetics

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2021

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Vol. 50, No. 2

315--333

EN

The article is devoted to the development and study of a model of a minimal risk portfolio under conditions of hybrid uncertainty of possibilistic-probabilistic type. In this model, the interaction of fuzzy parameters is described by both the strongest and the weakest triangular norms. The formula for variance of a portfolio is given that allows for estimating its risk. Models of acceptable portfolios are based on the principle of expected possibility or on the basis of fulfilling the restriction on the possibility/necessity and probability of the level of portfolio return that is acceptable to an investor. Equivalent deterministic analogues of the models are constructed and their solution methods are developed. Theorems describing a set of investment opportunities are proven. The obtained results are demonstrated on a model example.

4

Parametric Systems : Verification and Synthesis

Sofronie-Stokkermans Viorica

Fundamenta Informaticae

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2020

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Vol. 173, nr 2-3

91--138

EN

In this paper we study possibilities of using hierarchical reasoning, symbol elimination and model generation for the verification of parametric systems, where the parameters can be constants or functions. Our goal is to automatically provide guarantees that such systems satisfy certain safety or invariance conditions. We analyze the possibility of automatically generating such guarantees in the form of constraints on parameters. We illustrate our methods on several examples.

5

Fuzzy Model of 16PSK and 16QAM Modulation

Butkiewicz B. S.

International Journal of Electronics and Telecommunications

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2011

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Vol. 57, No. 4

437-442

EN

In the paper, a concept of Additive Fuzzy Noise (AFN) channel is introduced. The theoretical equations are derived for Bit Error Rate (BER) and Symbol Error Rate (SER) with some digital modulation scheme in the AFN channel. Following modulations are considered: Phase Shift Keying (16PSK), Quadrature Amplitude Modulation (16QAM). The fuzzy approach to these modulations is presented. The BER and SER values are calculated using possibility theory. The results obtained by fuzzy noise model are compared with conventional approach, where probability models of the noise are used.

6

Możliwości areologii

Burakowski T.

Inżynieria Materiałowa

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2006

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Vol. 27, nr 5

890-897

PL

Po raz pierwszy w literaturze omówiono możliwości - głównie w sensie zastosowań - aerologii: materiałów i technologii wytwarzania systemów areologicznych na częściach maszyn, narzędziach i urządzeniach, oraz najważniejsze właściwości tych systemów: twardość; odporność: korozyjną, trybologiczną i zmęczeniową, a także trwałość eksploatacyjną.

EN

First time intechnical letter on discus - generally in the sense of appication -materials and technology of areology systems produced on the machine parts, tools and installations as well as the properties of this systems: hardness, corrosion, tribology and fatique resistance, and exploitation durabilitythe.

7

What is not clear in fuzzy control systems?

Piegat A.

International Journal of Applied Mathematics and Computer Science

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2006

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Vol. 16, no 1

37-49

EN

The paper presents a number of unclear, unsolved or partly solved problems of fuzzy logic, which hinder precise transformation of expert knowledge about proper control of a plant in a fuzzy controller. These vague problems comprise the realization of logical and arithmetic operations and another basic problem, i.e., the construction of membership functions. The paper also indicates how some of the above problems can be solved.

8

Wpływ błędów kinematycznych na prawdopodobieństwo montażu cylindrycznych części maszyn.

Kluz R., Szabajkowicz W.

Technologia i Automatyzacja Montażu

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2005

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nr 2

14-17

9

A New Definition of the Fuzzy Set

Piegat A.

International Journal of Applied Mathematics and Computer Science

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2005

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Vol. 15, no 1

125-140

EN

The present fuzzy arithmetic based on Zadeh's possibilistic extension principle and on the classic definition of a fuzzy set has many essential drawbacks. Therefore its application to the solution of practical tasks is limited. In the paper a new definition of the fuzzy set is presented. The definition allows for a considerable fuzziness decrease in the number of arithmetic operations in comparison with the results produced by the present fuzzy arithmetic.

10

On practical problems with the explanation of the difference between possibility and probability

Piegat A.

Control and Cybernetics

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2005

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Vol. 34, no 2

505-524

EN

In his famous paper "Fuzzy Sets as a Basis for a Theory of Possibility" (Zadeh, 1978) Professor Lofti Zadeh introduced the notion of possibility distribution [pi]x and tlie concept of possibility measure. He denned in the paper the possibility distribution function to be numerically equal to the membership function ([pi]x = [my]F). In this paper Professor Zadeh draws the special attention of the reader to the fact that: "... there is a fundamental difference between probability and possibility". To explain this difference he had given a special example illustrating the difference, which then was cited by many authors of books on Fuzzy Set Theory and gained great importance for understanding the notion of possibility. In the paper the author presents his doubts as to this important example, explains why it is incorrect and gives a correct version of the example based on the notion of possibility distribution of Dubois and Prade.