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Abstract

In this article, we propose the realization of XNOR logic function by using all-optical XOR and NOT logic gates. Initially, both XOR and NOT gates are designed, simulated and optimized for high contrast outputs. T-shaped waveguides are created on the photonic crystal platform to realize these logic gates. An extra input is used to perform the inversion operation in the NOT gate. Inputs in both the gates are applied with out of phase so as to have a destructive interference between them and produce negligible intensity for logic ‘0'. The XOR and NOT gates are simulated using Finite Difference Time Domain method which results with a high contrast ratio of 55.23 dB and 54.83 dB, respectively at a response time of 0.136 ps and 0.1256 ps. Later, both the gates are cascaded by superimposing the output branch of the waveguide of XOR gate with the input branch of the waveguide of NOT gate so that it can be resulted with compact size for XNOR logic function. The resultant structure of XNOR logic came out with the contrast ratio of 12.27 dB at a response time of 0.1588 ps. Finally, it can be concluded that the proposed structures with fair output performance can suitably be applied in the design of photonic integrated circuits for high speed computing and telecommunication systems.

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Authors and Affiliations

E.H. Shaik
N. Rangaswamy
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Abstract

The waste production is closely related with human activity. Various approaches have been applied to manage and reduce its increasing volume (Paranjpe et al. 2023). One of the possibilities that comply with the assumptions of circular economy is utilization of wastes in anaerobic digestion (AD) process. This technology is common worldwide and it is recognized as the cost-effective methods of energy generation that also allow for nutrient recovery, as well as effective waste management (Alharbi et al. 2023). The biogas generated within this process is considered as a multifunctional renewable source that might be a promising alternative to the depleting traditional fuels. It finds various applications such as heat and power generation, fuel in automobiles, and substrate in chemical industry (Shitophyta et al. 2022, Pradeshwaran 2024). Typically, biogas contains 50–70% of CH4, 30–50% of CO2, and 1–10% of other trace gases like H2, H2S, CO, N2. Its composition mainly depends on the feedstock characteristics, operational conditions, and adopted technology (Gani et al. 2023, Archana et al. 2024). Considering further application, the priority action should be increasing its volume and methane content. There are several strategies to achieve these goals, including implementing codigestion strategy, adding additional component to the main substrate, introducing trace elements essential in AD, pretreatment strategies, and introducing enzymes and microbial strains to digesters (Zhang et al. 2019). Each method has limits related to the implementation costs, changes in the adopted technology, operator training needs, and additional energy input, which might negatively influence the energy balance of wastewater treatment plants (WWTPs) (Meng et al. 2022). Therefore, recent scientific attention has focused on combining various strategies to achieve intended goals. Moreover, such combinations might allow for an effective utilization of various wastes, the earlier use of which in AD was difficult. Orange waste could be an example of such a substrate. The previous studies indicated that its application in AD resulted in poor process efficiency, mainly due to the presence of limonene, recognized as the main inhibitor of biological activity (Calabro et al. 2020, Bouaita et al. 2022). In this study, the novel concept of implementing solidified carbon dioxide (SCO2) in the anaerobic co-digestion of municipal sewage sludge (SS) and orange peel waste (OPW) has been proposed. This approach may help overcome the disadvantages of the two-component AD of these wastes. Importantly, such studies have not been conducted thus far. However, the recent studies indicated that application of SCO2 to aerobic granular sludge improved biogas and methane yields and also enhanced the kinetics of biogas production (Kazimierowicz et al. 2023 a,b). Importantly, SCO2 might be generated in biogas upgrading technologies (Yousef 2019). Such solution is consistent with the principles of the circular economy and contributes to reducing the carbon footprint of WWTPs.
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Bibliography

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Authors and Affiliations

Aleksandra Szaja
1
ORCID: ORCID
Izabela Bartkowska
2

  1. Lublin University of Technology, Faculty of Environmental Engineering, Lublin, Poland
  2. Bialystok University of Technology, Department of Water Supply and Sewage Systems,Faculty of Civil Engineering and Environmental Sciences, Poland
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Abstract

Given the whole spectrum of doubts and controversies that arise in discussions about laws affecting historical memory (and their subcategory of memory laws), the question of assessing them in the context of international standards of human rights protection – and in particular the European system of human rights protection – is often overlooked. Thus this article focuses on the implications and conditions for introducing memory laws in light of international human rights standards using selected examples of various types of recently-adopted Polish memory laws as case studies. The authors begin with a brief description of the phenomenon of memory laws and the most significant threats that they pose to the protection of international human rights standards. The following sections analyse selected Polish laws affecting historical memory vis-à-vis these standards. The analysis covers non-binding declaratory laws affecting historical memory, and acts that include criminal law sanctions. The article attempts to sketch the circumstances linking laws affecting historical memory with the human rights protection standards, including those entailed both in binding treaties and other instruments of international law.

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Authors and Affiliations

Aleksandra Gliszczyńska-Grabias
ORCID: ORCID
Grażyna Baranowska
ORCID: ORCID
Anna Wójcik
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Abstract

This paper presents the results of modeling and analysis of hybrid generation system (HSW). The system contains municipal waste gasification installation, photovoltaic (PV) system and wind farm. The system cooperates with the power system to provide electrical energy to the communal consumer. The consumer is characterized by a maximum power demand equal to 10 MW and an annual energy demand of 42.351 GWh. Generation with renewable sources was modelled using meteorological data. Moreover, in order to cover the demand with the level of generation, gas storage was used. Next, the three-stage gasification model is presented. It was validated, using the literature data, and its efficiency and gas composition have been calculated and are presented. Furthermore, energetic and economic analysis have been conducted. Installed power usage factor and efficiency of energy sources were calculated. Gross and net energy generation of hybrid generation systems have been computed and are presented. In this analysis, energy consumption by gas compressing was included. The analyzed HSW covered 54.5% of the demand. Most of this (30.2%) was covered by the gasification system. However, the system was characterized by a low net efficiency equal to 16.7%. Diagrams of power generation in each source and storage fill chart are presented. In the economic part of the analysis, results of calculations of net present value and payback period are published in order to examine the profitability of the system.
The cost of electricity was 490–1050 PLN/MWh. The results show that municipal waste gasification can be used as a part of HSW to adjust the generation with the demand. Moreover, it can be economically advantageous. However, it is characterized by high CO 2 emission and low efficiency of the waste processing system.
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Authors and Affiliations

Jacek Roman
1
ORCID: ORCID

  1. Institute of Electrical Power Engineering, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Poland
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Abstract

When conducting geodetic and gravimetric measurements, there is a problem of projecting them to the reference surface. Since the gravitational field is inhomogeneous under the real conditions, the problem arises of determining the corrections to the measured values of gravitational acceleration in order to use the obtained data for the subsequent solutions of projection problems. Currently, the solution to this problem is performed using a Bouguer reduction, which requires information about the internal structure of the upper layer of the earth’s surface, topography, etc. The purpose of this study is to develop a methodological approach that would allow to determine the reduction (projection) corrections for gravitational acceleration on technogenic and geodynamic polygons without using data about the distribution of surface layer density and topography. The research process is based on the use of mathematical analysis methods and a wide range of experimental geodetic and gravimetric measurements. In the course of the performed researches, an algorithm was obtained and a practical implementation of the determination of the corrections in the measured values of gravitational acceleration on the basis of geodetic and gravimetric measurements was carried out at the certain geodynamic polygon in order to bring all corrections to one level surface.

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Authors and Affiliations

Lev Perovych
Igor Perovych
Valeriy Gorlachuk
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Abstract

This paper presents a force-dynamics analysis of the meaning of English periphrastic causative verbs. It challenges the traditional categorization of causative semantics into direct and indirect causation and highlights the role of lexico-semantic elements such as (i) the balance of forces, (ii) the desirability of the causal effect, and (iii) the animacy of the causative entities in interaction. Combined together, these elements help define causative semantics and offer a new causative typology built on the categories of factitivity, manipulation and permission.

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Authors and Affiliations

Sami Chatti
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Abstract

This article explores the experiences of lesbian, gay, bisexual and transgender (LGBT) migrants from Central and Eastern Europe and the Former Soviet Union in Scotland. Drawing on interviews with 50 migrants, the article focuses on the experiences and aspirations which they articulate as being part of ‘a normal life’, and analyses them within broader conceptual understandings of security and ‘normal-ity’. We first examine how normality is equated with an improved economic position in Scotland, and look at the ways in which this engenders feelings of emotional security and well-being. We then explore how more positive experiences around sexuality and gender identity are key to a sense of emotional security – i.e. of feeling accepted as ‘normal’, being visible as an LGBT person but ‘blending in’ rather than standing out because of it. Finally we look at the ways in which the institutional framework in Scotland, in particular the presence of LGBT-affirmative legislation, is seen by participants to have a normalising effect within society, leading to a broader sense of inclusion and equality – found, again, to directly impact upon participants’ own feelings of security and emotional well-being. The article engages with literatures on migration and sexuality and provides an original contribution to both: through its focus upon sexuality, which remains unexplored in debates on ‘normality’ and migration in the UK; and by bringing a migration perspective to the debates in sexuality studies around the normal-ising effect of the law across Europe. By bringing these two perspectives together, we reveal the inter-rela-tionship between sexuality and other key spheres of our participants’ lives in order to better understand their experiences of migration and settlement.

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Authors and Affiliations

Francesca Stella
Moya Flynn
Anna Gawlewicz
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Abstract

Polycyclic aromatic hydrocarbons (PAI-ls) are persistent organic pollutants, ubiquitous in the whole environment. They are relatively well known and are still of interest due to their well documented carcinogenic and mutagenie properties. In ambient air of urban regions they mostly occur as adsorbed to particles of suspended dust. The richest in these compounds and therefore most hazardous to humans, fraction of dust is the fraction of the finest particles. The paper presents results of investigations of dust sampled with use of an impactor Dekati PM10 in Zabrze, a site typical of Upper Silesian conditions. While sampling, the impactor segregates sampled particles into four fractions by their aerodynamic diameters. Sixteen PAHs were determined in each fraction chromatographically. PAH content in the fraction of the finest particles, i.e. in PM1, was of particular interest.
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Authors and Affiliations

Krzysztof Klejnowski
Barbara Kozielska
Andrzej Krasa
Wioletta Rogula-Kozłowska
ORCID: ORCID
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Abstract

The Włocławek Hydroelectric Power Plant is one of Poland’s largest power-generation projects.
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Authors and Affiliations

Marcin Kmieciński
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Abstract

Gravitational waves are not a rare phenomenon that happens only once in a while in our universe. Rather, such waves pass through the Earth on a daily basis, generated by cosmic events of various types. Studying their origins can teach us a great deal about the universe at large.
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Authors and Affiliations

Amedeo Romagnolo
1

  1. Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences
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Abstract

Art has never aspired to wield authority to the same extent as science, because it left a wide margin for itself resulting from the intrinsic consent to the subjectivity of both the creator and the audience.
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Authors and Affiliations

Katarzyna Kasia
1

  1. Department of Culture Theory, Faculty of Management of Visual Culture, Academy of Fine Arts in Warsaw
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Abstract

Exploited lubricants are dangerous contaminants because of their toxicity and low biodegradability. In this study, microbial culture active in exploited lubricant oil Mobil I was isolated and inoculated to sandy soil containing 0.5 g of contaminant per 100 g of dry soil. Microorganisms were used as free cells and immobilizate on wood chips, soil was also properly supplied with water and nutrients. The bioaugumantation seems to enhance biodegradation process. After 5 months, 93% of non-polar compounds were eliminated from soil containing immobilized biomass. Comparatively, in non-treated soil (control system) the contaminant elimination was at the level of 47%. Bacterial number in treated and non-treated soil was similar for about 3 months; however enzymatic activity (dehydrogenascs and hydrolascs) in control soil was much lower. Finally, after 5 months of treatment the content of bacteria active in contaminant decomposition in inoculated soil was 100-fold higher than in control system. Presumably, the main reason of low remediation results in non-treated soil seems to be low enzymatic activity of the biomass.
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Authors and Affiliations

Ewa Zborowska
Jeremi Naumczyk
Ewelina Bugryn
Renata Wojciechowska
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Abstract

Is hydrogen the answer, and if so, which technologies? Here we present an overview of “everything you need to know” about this promising new global energy source.
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Authors and Affiliations

Tadeusz Chmielniak
1

  1. Faculty of Environmental and Power Engineering, Silesian University of Technology in Gliwice, Poland
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Abstract

Predictive mathematical models have useful applications in the food industry – preventing the loss and wastage of food, thereby conserving resources.
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Authors and Affiliations

Elżbieta Rosiak
1

  1. Institute of Human Nutrition SciencesWarsaw University of Life Sciences (SGGW)
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Abstract

Length, width, depth… Knowing these parameters allows us to judge which table will fit into our dining room, which bed is right for our bedroom. We use three measures to describe the space around us, but we rarely ask ourselves whether reality is, in fact, three-dimensional.
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Authors and Affiliations

Jan Chwedeńczuk
1

  1. Faculty of Physics, University of Warsaw
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Abstract

Wind power integration through the voltage source converter-based high-voltage direct current (VSC-HVDC) system will be a potential solution for delivering large-scale wind power to the “Three-North Regions” of China. However, the interaction between the doubly-fed induction generator (DFIG) and VSC-HVDC system may cause the risk of subsynchronous oscillation (SSO). This paper establishes a small-signal model of the VSC based multi-terminal direct current (VSC-MTDC) system with new energy access for the problem, and the influencing factors causing SSO are analyzed based on the eigenvalue analysis method. The theoretical analysis results show that the SSO in the system is related to the wind farm operating conditions, the rotor-side controller (RSC) of the DFIG and the interaction of the controller in the VSC-MTDC system. Then, the phase lag characteristic is obtained based on the signal test method, and a multi-channel variable-parameter subsynchronous damping controller (SSDC) is designed via selecting reasonable parameters. Finally, the correctness of the theoretical analysis and the effectiveness of the multi-channel variable-parameter SSDC are verified based on time-domain simulation.
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Authors and Affiliations

Miaohong Su
1
ORCID: ORCID
Haiying Dong
1 2
Kaiqi Liu
1
Weiwei Zou
1

  1. School of Automatic and Electrical Engineering, Lanzhou Jiaotong University, China
  2. School of New Energy and Power Engineering, Lanzhou Jiaotong University, China
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Abstract

Previous researchers have been widely studied the equation for calculating the energy dissipation in USBR Type IV, applied in the stilling basin structure as an energy dissipator. However, inefficient energy dissipating basins are commonly found in the field due to the large discharge and high water head, potentially damaging the bottom of the energy dissipating basin and its downstream river. Therefore, an energy dissipator plan fulfilling the safe specifications for the flow behaviour that occurred is required. This study aimed to determine the variation of the energy dissipators and evaluate their effect on the hydraulic jump and energy dissipation. For this purpose, a physical model was undertaken on the USBR Type IV spillway system. The novelty of this experiment showed that combination and modification dissipation features, such as floor elevation, end threshold and riprap lengthening, could effectively dissipate the impact of energy downstream. The final series exhibited a significantly higher Lj/y1 ratio, a favourable condition due to the compaction of the hydraulic jump. There was also a significant increase in the downstream tailwater depth (y2) during the jump formation. Therefore, the final series energy dissipator was better in the stilling basin design for hydraulic jump stability and compaction. The increase in energy dissipation for the final series type was the highest (98.4%) in Q2 and the lowest (84.8%) in Q10 compared to the original series. Therefore, this type can better reduce the cavitation risk damaging to the structure and downstream of the river.
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Authors and Affiliations

Alfiansyah Yulianur Bantacut
1
ORCID: ORCID
Azmeri Azmeri
1
ORCID: ORCID
Faris Zahran Jemi
2
ORCID: ORCID
Ziana Ziana
1
ORCID: ORCID
Muslem Muslem
1

  1. Universitas Syiah Kuala, Faculty of Engineering, Civil Engineering Department, Syech Abdur-Rauf No 7, Darussalam, 23111, Banda Aceh, Indonesia
  2. Universitas Syiah Kuala, Faculty of Engineering, Electrical Engineering Department, Banda Aceh, Indonesia
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Abstract

The presence of natural organic matter (NOM) in water has a significant influence on water treatment processes. Water industries around the world consider coagulation/flocculation to be one of the main water treatment methods. The chief objective of conventional coagulation-based processes is to reduce the turbidity of the water and to remove natural organic matter (NOM) present in solutions. The aim of this paper is to present some developments in terms of improved coagulation for the drinking water of Sidi Yacoub treatment plant located in the Northwest of Algeria.
The experiments involved studying the effects of the application of two coagulants (ferric chloride and aluminium sulphate) on the removal of turbidity and natural organic matter from water by measuring the chemical oxygen demand ( COD) and the UV absorbance at 254 nm. The results showed that the rate of turbidity removal increased from 81.3% to 88% when ferric chloride was applied and from 89.91% to 94% when aluminium sulphate was applied. For NOM removal, the maximum removal rates of COD and UV254 were 48% and 52%, respectively, in the case of ferric chloride. These rates increased to 59% and 65% after optimised coagulation. When aluminium sulphate was used, the rate of removal in water increased from 43% to 55% for COD and from 47% to 59% for UV254 after optimised coagulation. The combination of the two coagulants at equal dosage shows a slight improvement in the values obtained after optimisation, both in terms of turbidity and the NOM.
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Authors and Affiliations

Taieb Hadbi
1
ORCID: ORCID
Saaed Hamoudi Abdelamir
2

  1. University of Science and Technology Mohamed Boudiaf of Oran, Faculty of Architecture and Civil Engineering, El Mnaouar, BP 1505, Bir El Djir 31000, Oran, Algeria
  2. Hassiba Benbouali University of Chlef, Faculty of Civil Engineering and Architecture, Chlef, Algeria
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Abstract

Zeolites, minerals with the formula Mx/n[AlO2]x(SiO2)y] zH2O, are environmentally friendly materials used as water treatment adsorbents, gas adsorbents, and petrochemical catalysts. This study used a mixture of aluminum black dross and waste glass to synthesize zeolites via a hydrothermal synthesis and analyzed the effects of varying reaction time on phase changes under different synthesis conditions. With increased reaction times, a phase change from zeolite Na-P1 to analcime was observed; on employing hydrothermal synthesis at 150°C for 96 h, the majority of the crystalline structures changed into analcime. Heavy metal cation adsorption was tested to assess the applicability of the synthesized analcime to water treatment. Zeolite adsorption of at least 95% was observed for both Pd and Cd ions. Although a higher level of adsorption was observed for Pb ion than Cd ion, Cd ion was demonstrated to undergo relatively faster adsorption when tested under optimal pulp density at the same level of adsorption (95%).
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Authors and Affiliations

Yubin Kang
1
ORCID: ORCID
Byoungyong Im
1
ORCID: ORCID
Jin-Ju Choi
1
ORCID: ORCID
Jin-Ho Yoon
1
ORCID: ORCID
Dae-Guen Kim
1
ORCID: ORCID

  1. Institute For Advanced Engineering, 17180, Goan-ro, 51 Beon-gil, Baegam-myeon, Cheoin-gu, Yongin-si, Gyeonggi-do, Korea
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Abstract

The paper aims was assessing risks of mandible fractures consequent to impacts or sport accidents. The role of the structural stiffness of mandible, related to disocclusion state, was evaluated using the finite element method. It has been assumed, that the quasi-static stress field, due to distributed forces developed during accidents, could explain the common types of mandibular fractures. Mandibular condyles were supposed jammed in the maxillary fossae. The force of 700 N, simulating an impact on mandible, has been sequentially applied in three distinct areas: centrally, at canine zone and at the mandibular angle. Clinically most frequent fractures of mandible were recognized through the analysis of maximal principal stress/strain fields. It has been shown that mandibular fracture during accidents can be analyzed at satisfactory level using linear quasi-static models for designing protections.

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Authors and Affiliations

J. Żmudzki
G. Chladek
K. Panek
P. Lipiński

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