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Number of results: 95
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Abstract

This paper examines the notion of conceptual transfer within the framework of current psycholinguistic research into bilingual memory and multi-competence. In particular, it seeks to delimit the form and direction of conceptual transfer in the bilingual lexicon, as well as outlining the conditions for its occurrence. These are discussed in relation to the data collection methods employed to date, and in the light of recent findings and developments in the area of psycholinguistics and bilingualism.
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Authors and Affiliations

Jolanta Latkowska
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Abstract

The divergence between Russia and Western States on the question whether international humanitarian law (IHL) applies to cyber space is still omnipresent in the debates at the UN Open-ended Working Group. Russia has several times submitted a draft or a concept for a binding legal instrument; however, they have not included considerable suggestions on IHL. Furthermore, Russia is actively using cyber means in an aggressive war against Ukraine, which makes its calls sound hollow. How then can one explain Russia’s quest for a treaty for cyberspace, especially regarding IHL? This article aims to shed some light on this question in the broader context of Russian approaches to international law-making and its historic role in developing IHL rules.
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Authors and Affiliations

Liina Lumiste
1
ORCID: ORCID

  1. University of Tartu (Estonia)
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Abstract

Erosion and sedimentation have a very big influence on flooding. Floods are strongly influenced by land use and population activities that change the river’s physical condition, including erosion and sedimentation. The river upstream was very steep, and the downstream was narrowing and meandering with high rainfall recorded. This study analyses erosion, sedimentation, and its handling using the eco-hydraulic base. The method involves input rainfall data, river hydraulics, land use, watershed area, and land cover. The analysis of hydrology, hydraulics, land use, flood discharge, and eco-hydraulic, inundation height, vegetation diameter, velocity reduced, and riverbank width measured in five bridges cross-sections along the river. The eco-hydraulic compares the width of existing riverbanks and design, high inundation, and the vegetation diameter to minimise flood discharge. Erosion in the right cliff is 22.73% and the left cliff is 37.04%, land erosion was 225.83 Mg∙ha –1∙year –1. The river’s bottom is formed by rocks of 0.18–1.30 mm. The plantation land used around the Lae Kombih River grows mainly an oil palm with a diameter of 0.5–0.7 m. The riverbank design on 100 m for vegetation diameter of 0.1–1.0 m can retain flood discharge for five years return period up to 72.3%, resulting in discharge of 112.04209.43 m 3∙s –1. The largest erosion and sedimentation on the river border is Dusun Silak, so it is recommended to plant Vetiveria zizanioides, Ipomoea carnea and Bambusoideae. An inundation height of 0.9 m can be recommended to design an embankment to be used as flood mitigation.
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Authors and Affiliations

Ziana Ziana
1 2
ORCID: ORCID
Azmeri Azmeri
1 2
ORCID: ORCID
Alfiansyah Yulianur
1 2
ORCID: ORCID
Ella Meilianda
1 2
ORCID: ORCID

  1. Universitas Syiah Kuala, Doctoral Program, School of Engineering, Banda Aceh, 23111, Indonesia
  2. Universitas Syiah Kuala, Department of Civil Engineering, Banda Aceh, 23111, Indonesia
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Abstract

We study the evolution of income and wealth inequality in an economy undergoing endogenous structural change with imperfect labor mobility. Our economy features two sectors: services and manufacturing. With faster TFP growth in manufacturing, labor reallocates from manufacturing to services. This reallocation is slower due to labor mobility frictions, which in turn, raises relative wages in services. As a result, income inequality is higher. Moreover, we study the impact of structural change on wealth inequality. Its economic intuition is more ambiguous. On the one hand, increased income dispersion implies increased dispersion in the ability to accumulate wealth across individuals. On the other hand, younger workers who hold the least assets are the most mobile across sectors. Their incomes are improved, which boosts their savings, which works towards equalizing wealth distribution. The consequence of these changes can only be verified with a computational model. To this end, we construct an overlapping generations model with two sectors: manufacturing and services. Our model also features heterogeneous individuals. With our model, we are able to show how the structural change affected the evolution of income and wealth inequality in Poland as of 1990.
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Authors and Affiliations

Krzysztof Makarski
1
Joanna Tyrowicz
2

  1. SGH Warsaw School of Economics and FAME|GRAPE
  2. FAME|GRAPE, University of Regensburg, University of Warsaw, and IZA
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Abstract

The hemostasis system is designed to ensure the integrity of the body’s internal environment, stop bleeding, and maintain a liquid state of blood in the vascular channel. Modern biological and veterinary science presents highly fragmented and scarce data containing clinical and diagnostic clotting characteristics in different fish species. An essential point emphasising the practical component of such studies is spontaneous thrombus formation in fish farming described in the literature. The present research is devoted to the study of the functional state of plasma hemostasis in some ray- finned commercial fishes: phylogenetically more ancient cartilaginous ganoids – sturgeon Acipenser baerii and hybrid of sterlet A. ruthenus and starred sturgeon A. stellatus, as well as bony fishes – carp Cyprinus carpio and tilapia Oreochromis niloticus. It should be noted that the current study was performed at the aquaculture development center “AquaBioCenter” of VSDFA from 2015 to 2020. Species-specific features of clotting were revealed: activation by common and extrinsic pathways, characterised by thrombin time ( TT), prothrombin time ( PT), and fibrinogen concentration, is several times faster in cartilaginous ganoids than in both bony fish species; hemostasis with activation of the intrinsic pathway, characterised by activated partial thromboplastin time ( APTT), is faster in hybrids and tilapias, in contrast to carps and sturgeons. Content of soluble fibrin monomer complexes ( SFMC) in all fish was higher than in dogs and humans but lower than in cattle. The highest amount of SFMC was detected in carps, the lowest – in cartilaginous ganoids.
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Authors and Affiliations

Holya Alobaidy
1
ORCID: ORCID
Hayder Dawood Saleem
2
ORCID: ORCID
Aiman Mohammed Baqir Al-Dhalimy
3 4
ORCID: ORCID

  1. Al-Nisour University College, College of Science, Nisour Square Tunnel 8934+85M, Baghdad, Iraq
  2. Al-Manara College For Medical Sciences, Department of Dentistry, Misan, Iraq
  3. Altoosi University College, College of Nursing, Najaf, Iraq
  4. Islamic University of Najaf, Najaf, Iraq
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Abstract

This study investigates Thomas’ cyclically symmetric attractor dynamics with mathematical and electronic simulations using a proportional fractional derivative to comprehend the dynamics of a given chaotic system. The three-dimensional chaotic flow was examined in detail with Riemann-Liouville derivative for different values of the fractional index to highlight the sensitivity of chaotic systems with initial conditions. Thus, the dynamics of the fractional index system were investigated with Eigenvalues, Kaplan–Yorke dimension, Lyapunov exponent, and NIST testing, and their corresponding trajectories were visualized with phase portraits, 2D density plot, and Poincaré maps. After obtaining the results, we found that the integer index dynamics are more complex than the fractional index dynamics. Furthermore, the chaotic system circuit is simulated with operational amplifiers for different fractional indices to generate analog signals of the symmetric attractor, making it an important aspect of engineering. The qualitative application of our nonlinear chaotic system is then applied to encrypt different data types such as voice, image, and video, to ensure that the developed nonlinear chaotic system can widely applied in the field of cyber security.
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Authors and Affiliations

NajeebAlam Khan
1
Muhammad Ali Qureshi
2
Saeed Akbar
1
Asmat Ara
3

  1. Department of Mathematics, University of Karachi, Karachi 75270, Pakistan
  2. Department of Physics, University of Karachi, Karachi 75270, Pakistan
  3. College of Humanities and Sciences, PAF-KIET, Karachi 75190, Pakistan
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Abstract

A multiple regression model approach was developed to estimate buffering indices, as well as biogas and methane productions in an upflow anaerobic sludge blanket (UASB) reactor treating coffee wet wastewater. Five input variables measured (pH, alkalinity, outlet VFA concentration, and total and soluble COD removal) were selected to develop the best models to identify their importance on methanation. Optimal regression models were selected based on four statistical performance criteria, viz. Mallow’s Cp statistic (Cp), Akaike information criterion ( AIC), Hannan– Quinn criterion ( HQC), and Schwarz–Bayesian information criterion ( SBIC). The performance of the models selected were assessed through several descriptive statistics such as measure of goodness-of-fit test (coefficient of multiple determination, R2; adjusted coefficient of multiple determination, Adj-R2; standard error of estimation, SEE; and Durbin–Watson statistic, DWS), and statistics on the prediction errors (mean squared error, MSE; mean absolute error, MAE; mean absolute percentage error, MAPE; mean error, ME and mean percentage error, MPE). The estimated model reveals that buffering indices are strongly influenced by three variables (volatile fatty acids (VFA) concentration, soluble COD removal, and alkalinity); while, pH, VFA concentration and total COD removal were the most significant independent variables in biogas and methane production. The developed equation models obtained in this study, could be a powerful tool to predict the functionability and stability for the UASB system.
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Authors and Affiliations

Yans Guardia-Puebla
1
ORCID: ORCID
Edilberto Llanes-Cedeño
2
ORCID: ORCID
Ana Velia Domínguez-León
3
Quirino Arias-Cedeño
1
ORCID: ORCID
Víctor Sánchez-Girón
4
ORCID: ORCID
Gert Morscheck
5
Bettina Eichler-Löbermann
5
ORCID: ORCID

  1. University of Granma, Study Center for Applied Chemistry, Cuba
  2. Faculty of Architecture and Engineering, International SEK University, Quito, Ecuador
  3. Language Center, University of Granma, Cuba
  4. College of Agricultural, Food and Biosystems Engineering, Technical University of Madrid, Spain
  5. Faculty of Agronomy and Crop Science, University of Rostock, Germany
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Abstract

The following paper aims to analyse the functions of the interjection oh in the English corpus provided by Helen Fielding’s Bridget Jones’s Diary and its translation into Polish. Once the functions and patterns of the form are defined, the translation strategies employed are analysed. The study reveals which translational strategies proposed by Cuenca (2006) are employed in the translation of oh: literal translation, using an interjection with dissimilar form but having the same meaning, using a non‑interjective structure but with similar meaning, using an interjection with a different meaning, omission, or addition of usually a primary interjection. The analysis of the interjection oh is preceded by a very brief presentation of various approaches focusing on the problem of defining and classifying interjections, as well as the presentation of the research concerning the interjection oh and its description in the specialist literature.
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Authors and Affiliations

Anna Drzazga
1

  1. University of Silesia in Katowice
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Abstract

The essay will focus on a mid-nineteenth century medallion from the vast collection of Polish bibliophile Ludwik Gocel (1889–1966). Made in 1854 in the U.S. capital, Washington, D.C., it depicts a prominent nineteenth century American, Judge Charles Mason (1804–1882), and is a valuable token of the U.S. history. It was designed and completed by Polish distinguished medalist, Henryk Dmochowski (in the U.S. known as Henry Dmochowski Saunders; b. 1810–d. 1863) who can be called a “soldier-artist,” since he participated in three Polish uprisings. Expelled from partitioned Poland, in 1851 he came to America where he was offered the chance to work as a sculptor. This essay’s main aim is to describe the fate of the medallion, apparently almost unknown in both America and Poland, with special emphasis on the role of Ludwik Gocel in its preservation. This rare piece of art has never been included in Polish or American art publications in the field of sculpture.
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Authors and Affiliations

Jacek Serwański
1
ORCID: ORCID

  1. The Institute of Slavic Studies, Polish Academy of Sciences, Warsaw, Poland
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Abstract

This paper reports a new strand wire winding method in a solenoidal coil with limited geometry that enables good impedance matching. In the proposed method strand wires are wound layer-by-layer on top of each other allowing one to set equivalent inductance and resistance of the coil to desired values while obtaining dense magnetic flux and high current carrying capacity. As a proof-of-concept demonstration, simple model setups were constructed with solenoidal coils composed of copper wire strands wound according to the proposed method, and a plastic pipe. The measurements were repeated with a metal shell placed inside the coil to model a complete heating system. System inductance and resistance were measured at two different frequencies. The results show that with the new winding method it is possible to increase a coil’s turn number and the number of strand layers composed by the coil. Also, adding and removing strand layers in the proposed coil architectures enable inductance and resistance values to decrease and increase, respectively, in a controlled way. To understand changes of system parameters, simulations were also performed. The calculated inductance and resistance values in the simulations agree well with the measurement results and magnetic flux distribution created in the system demonstrates the changes.
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Authors and Affiliations

Veli Tayfun Kilic
1

  1. Department of Electrical and Electronics Engineering, Abdullah Gul University, Kayseri, Turkiye
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Abstract

In this article attention is paid to improving the quality of text document classification. The common techniques of analysis of text documents used in classification are shown and the weakness of these methods are stressed. Discussed here is the integration of quantitative and qualitative methods, which is increasing the quality of classification. In the proposed approach the expanded terms, obtained by using information patterns are used in the Latent Semantic Analysis. Finally empirical research is presented and based upon the quality measures of the text document classification, the effectiveness of the proposed approach is proved.

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Authors and Affiliations

Bożena Śmiałkowska
Marcin Gibert
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Abstract

The article aims to discuss foreign language writing anxiety and present the results of the study which was to investigate whether writing apprehension can be observed among advanced adult learners of English. Analysing anxiety from a three dimensional perspective proposed by Lang (1971) the study revealed that advanced adult students most intensely experience cognitive anxiety whose most prevailing symptoms are panic, worry and elements of test anxiety. Somatic anxiety has also been observed in this group of participants with heart pounding, freezing up, mind going blank and jumbled thoughts as the most common symptoms. Finally, the research revealed that avoidance behaviour appears infrequently among advanced writers. The research results have been used as the basis for formulating pedagogical implications on how to reduce students’ writing apprehension.

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Authors and Affiliations

Małgorzata Marzec-Stawiarska
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Abstract

Levels and distribution of selected polybrorninated diphenyl ether congeners in dust samples taken from different indoor environments in Lublin, South-Eastern Poland, are reported. The most abundant congeners, found in the majority of sampling sites, were BOE 47, 100 and 28, respectively. The highest levels of examined congeners were observed in dust samples taken from a computer repair facility and labs. BOE 47, 99 and 100, occurring at highest levels and having the greatest contribution confirm that in Polish indoor environments polymer products contain Penta - BOE technical mixture.
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Authors and Affiliations

Amelia Staszowska
Bernard Połednik
Marzenna R. Dudzińska
Jacek Czerwiński
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Abstract

The paper presents the results of assessment studies of the time course for technical wear in masonry buildings located in the area of mining-induced ground deformations. By using fuzzy inference system (FIS) and the “if-then” rule, corresponding language labels describing actual damage recorded in structure components were translated into scalar outputs describing the degree of damage to the building. Adopting this approach made it possible to separate damage resulting from additional effects coming from mining-induced ground deformations and the natural wear and tear of masonry structure. By using statistical analysis an exponential function for the condition of building damage and the function of natural wear and tear were developed. Both phenomena were subject to studies as a function of time regarding the technical age of building structure. The results obtained were used to develop a model for the course of technical wear of traditionally constructed buildings used within mining areas.

In the course of natural wear and tear buildings located in mining areas are additionally exposed to forced ground deformations. The increase of internal forces in structure components induced by those effects results in creating an additional stress factor and damage. The hairline cracks and cracks of building structure components take place when the intensity value of mining effects becomes higher than the component stress resistance and repeated effects result in the decrease of structure rigidity. The observations of building behaviour in mining areas show that the intensity of mining activity and the multiplicity of its effect play a substantial role in the course of technical wear of buildings. The studies show that the level of damage resulting from mining effects adds up to natural wear and tear of the building and impairs the global technical condition as compared to similar buildings used outside mining areas.

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Authors and Affiliations

Izabela Dorota Bryt-Nitarska
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Abstract

This paper shows the possibility that the mineral coal existing in the mining basins of northern Spain have a high added value. This would facilitate its future use in different fields such as new materials, nanotechnology, energy use in situ, coal bed methane, enhanced coal bed methane and coalmine methane.

An analytical study of mineral coal samples is carried out. The samples come from two deposits located in coal basins of the Cantabrian Mountains. The duly prepared samples are subjected to an activation process. Within this transformation, different treatments are applied to different sub-samples. Some of the sub-samples suffer a previous demineralization by successive attacks with acids, followed by oxidation and pyrolysis. Finally, all of them are activated with CO2 and H2O(steam).

The carbonaceous products resulting from each treatment are characterised. The results show that all the pre-treatments used were positive for the textural development of the materials. Likewise, proper management of the processes and of the different operating variables allows the procurement of carbonaceous materials with a “tailor-made” structural development of the coal type. This material receives the name “activated” and can be employed in specific processes.

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Authors and Affiliations

Juan-José Vidal-Lombas
Martina-Inmaculada Álvarez-Fernández
María-Concepción Casado-Sulé
Maria-Belen Prendes-Gero
Francisco-José Suárez-Domínguez
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Abstract

The Euler multiphase flow and population equilibrium model were used to simulate the three-phase flow field in the bubble expansion stage of the outlet curved pipe section. The influence of the ratio of the bending diameter and the volume fraction of the gas phase on the pressure loss is revealed, and the safety range of the optimum bending diameter ratio and the volume fraction of the outlet gas phase is determined. The results show that the three-phase flow in the tube is more uniformly distributed in the vertical stage, and when the pipe is curved, the liquid-phase close to the pipe wall gathers along the pipe flank to the outside of the pipe, the solid phase is transferred along the pipe flank to the inside of the pipe, and the gas phase shrinks along the pipe flank to the inner centre. The maximum speed of each phase of the three-phase flow in the elbow is at the wall of the tube from 45° to 60° inside the elbow, and the distribution law along the axial direction of the pipe is about the same as the distribution law of volume fraction. The pressure loss of the elbow decreases with the increase of the bend diameter ratio, when the bend diameter ratio increases to 6, the pressure loss of the pipe decreases sharply, and the pressure loss decreases slowly with the increase of the bend diameter ratio. When the gas phase volume score in the elbow reaches 70%, there will be an obvious wall separation phenomenon, to keep the system in a stable working state and prevent blowout, the gas phase volume score should be controlled within 60%.
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Authors and Affiliations

Wei Chen
1 2 3
ORCID: ORCID
Hai-liang Xu
2 3
ORCID: ORCID
Bo Wu
2 3
ORCID: ORCID
Fang-qiong Yang
2 3
ORCID: ORCID

  1. Hunan University of Humanities, Department of Energy and Electrical Engineering, Science and Technology, Loudi, Hunan 417000, China
  2. Central South University, School of Mechanical and Electrical Engineering, Changsha, Hunan 410083, China
  3. State Key Laboratory of High Performance Complex Manufacturing, Changsha, Hunan 410083, China
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Abstract

This work describes a dual band compact fully integrated rectenna circuit for implantable medical devices (IMDs). The implantable rectenna circuit consists of tunnel diode 10×10μm2 QW-ASPAT (Quantum Well Asymmetric Spacer Tunnel Layer diode) was used as the RF-DC rectifier due to its temperature insensitivity and nonlinearity compared with conventional SBD diode. SILVACO atlas software is used to design and simulate 100μm2 QW InGaAs ASPAT diode. A miniaturized dual band implantable folded dipole antenna with multiple L-shaped conducting sections is designed using CST microwave suits for operation in the WMTS band is 1.5GHz and ISM band of 5.8GHz. High dielectric constant material Gallium Arsenide (εr=12.94) and folded geometry helps to design compact antennas with a small footprint of 2.84mm3 (1×4.5×0.63) mm3. Four-layer human tissue model was used, where the antenna was implanted in the skin model at depth of 2mm. The 10-dB impedance bandwidth of the proposed compact antenna at 1.5GHz and 5.8GHz are 227MHz (1.4-1.63GHz) with S11 is -22.6dB and 540MHz (5.47-6.02GHz) with S11 is -23.1dB, whereas gains are -36.9dBi, and -24.3dBi, respectively. The output DC voltage and power of the rectenna using two stage voltage doubler rectifier (VDR) are twice that produced by the single stage at input RF power of 10dBm.
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Authors and Affiliations

Shamil H. Hussein
1
Khalid K. Mohammed
1 2

  1. Faculty of Engineering University of Mosul, Iraq
  2. University of Nineveh, Iraq
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Abstract

This paper describes the author’s method for the direct and continuous measurement of the temperature distribution during the initial period of hardening concrete, together with the results of tests obtained with its use. The first successful test using this method was conducted by the author in May 2001 [7]. In the following years, the author successfully used this method in the study of other structural elements [8] and [9]. He independently developed and made the necessary elements to measure the temperature in hardening concrete. The tested element is a reinforced concrete column with a diameter of 2.0 m and a height of 8.0 m, which is an intermediate support for the flyover under construction along the Wrocław city ring road. The structure consists of two independent continuous 15-span structures made of pre-stressed concrete (Fig. 1). The article additionally presents numerical model of the previously tested reinforced concrete pillar and the calculation results obtained. The numerical calculations were carried out using the Abaqus FEA software [1]. In conclusions, the author summarises the important elements of the on-site test and makes recommendations for further use of this method to predict the temperature distribution in other elements of the structure, provided that they are made of exactly the same concrete mixture.
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Authors and Affiliations

Andrzej Helowicz
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Faculty of Civil Engineering,Na Grobli 15, 50-421 Wrocław, Poland
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Abstract

Continuous steel-concrete composite girder can fully utilize material strength and possess large spanning ability for bridge constructions. However, the weak cracking resistance at the negative bending moment region of the girder seriously harms its durability and serviceability. This paper investigates practical techniques to improve the cracking performance of continuous steel-concrete composite girders subjected to hogging moment.Areal continuous girderwas selected as the background bridge and introduced for numerical analysis. Modeling results show that under the serviceability limit state, the principle stress of concrete slabs near the middle piers of the bridgewas far beyond the allowable material strength, producing a maximum tensile stress of 10.0 MPa. Approaches for strengthening concrete decks at the negative moment region were developed and the effectiveness of each approach was assessed by examing the tensile stress in the slabs. Results indicate that the temporary counterweight approach decreased the maximum tensile stress in concrete slabs by 22%. Due to concrete shrinkage and creep, more than 65% of the prestressed compressive stresses in concrete slabs were finally dispersed to the steel beams. A thin ultra-high performance concrete (UHPC) overlay at the hogging moment region effectively increased the cracking resistance of the slabs, and practical engineering results convicted the applicability of the UHPC technique.
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Authors and Affiliations

Min Cai
1
ORCID: ORCID
Wenjie Li
2
ORCID: ORCID
Zhiyong Wan
3
ORCID: ORCID
Jianjun Sheng
1
ORCID: ORCID
Juliang Tan
4
ORCID: ORCID
Chao Ma
1
ORCID: ORCID

  1. Guangdong Highway Construction Co., LTD, 510623 Guangzhou, China
  2. Guangdong Yunmao Expressway Co. Ltd, 525346 Guangzhou, China
  3. Guangdong Communication Planning & Design Institute Co., Ltd,510507 Guangzhou, China
  4. Guangdong Communication Planning & Design Institute Co., Ltd, 510507 Guangzhou, China
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Abstract

The problem of setting out in civil engineering applications has been addressed in the literature for a long time. However, technological development has provided researchers with an opportunity of having other procedures in line with modern techniques in surveying sciences. One of the most important procedures in erecting steel structures, bridges, and precast columns of a building is the accurate placement of the anchorage system in concrete. The traditional method for staking out anchor bolts relies on sight rails, string lines, and tape measure. The precision of this art depends not only on the accuracy of observed offset distances during layout operations but also on the centerline of the anchoring template itself. Nowadays, the process of designing structures is executed using software that can perform a digital plan in CAD environment, where the coordinates of each anchor bolt can be defined. This research presents an accurate approach of positioning anchor bolts based on the second problem in surveying and total station. Error analysis and field application are described to evaluate the performance of the proposed method. However, the results indicate that the developed technique increases productivity, reduces the cost, and improves the positional accuracy.

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Authors and Affiliations

M. Habib
A. Malkawi
M. Awwad
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Abstract

Robots that can comprehend and navigate their surroundings independently on their own are considered intelligent mobile robots (MR). Using a sophisticated set of controllers, artificial intelligence (AI), deep learning (DL), machine learning (ML), sensors, and computation for navigation, MR's can understand and navigate around their environments without even being connected to a cabled source of power. Mobility and intelligence are fundamental drivers of autonomous robots that are intended for their planned operations. They are becoming popular in a variety of fields, including business, industry, healthcare, education, government, agriculture, military operations, and even domestic settings, to optimize everyday activities. We describe different controllers, including proportional integral derivative (PID) controllers, model predictive controllers (MPCs), fuzzy logic controllers (FLCs), and reinforcement learning controllers used in robotics science. The main objective of this article is to demonstrate a comprehensive idea and basic working principle of controllers utilized by mobile robots (MR) for navigation. This work thoroughly investigates several available books and literature to provide a better understanding of the navigation strategies taken by MR. Future research trends and possible challenges to optimizing the MR navigation system are also discussed.
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Authors and Affiliations

Ravi Raj
1
ORCID: ORCID
Andrzej Kos
1

  1. Faculty of Computer Science, Electronics, and Telecommunications, AGH University of Science and Technology, Krakow, Poland
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Abstract

51 samples from the Middle Triassic black shales (organic carbon−rich silt− stones; up to 4.9% TOC – Total Organic Carbon) from the stratotype section of the Bravaisberget Formation (western Spitsbergen) were analyzed with respect to isotopic composition of pyritic sulphur (δ34S) and TOC. Isotopic composition of syngenetic py− rite−bound sulphur shows wide (δ34S from −26‰ to +8‰ VCDT) and narrow (δ34S from −4‰ to +17‰ VCDT) variation of the δ34S in upper and lower part of the section, respec− tively. Range of the variation is associated with abrupt changes in dominant lithology. Wide δ34S variation is found in lithological intervals characterized by alternation of black shales and phosphorite−bearing sandstones. The narrow δ34S variation is associated with the lithological interval dominated by black shales only. Wide and narrow variation of the δ34S values suggests interplay of various factors in sedimentary environment. These fac− tors include oxygen concentration, clastic sedimentation rate, bottom currents and bur− rowing activity. Biological productivity and rate of dissimilatory sulphate reduction had important impact on the δ34S variation as well. Wide variation of the δ34S values in the studied section resulted from high biological productivity and high rate of dissimilatory sulphate reduction. Variable degree of clastic sedimentation rate and burrowing activity as well as the activity of poorly oxygenated bottom currents could also cause a co−occurrence of isotopically light and heavy pyrite in differentiated diagenetic micro−environments. Occurrence of organic matter depleted in hydrogen could also result in a wide variation of the δ34S values. Narrow variation of the δ34S values was due to a decrease of biological productivity and low rate of dissimilatory sulphate reduction. Low organic matter supply, low oxygen concentration and bottom currents and burrowing activity were also responsible for narrow variation of the δ34S. The narrow range of the δ34S variation was also due to occurrence of hydrogen−rich organic matter. In the studied section the major change in range of the δ34S variation from wide to narrow appears to be abrupt and clearly associated with change in lithology. The change of lithology and isotopic valuesmay sug− gest evolution of the sedimentary environment from high− to low−energy and also facies succession from shallow to deeper shelf. The evolution should be linked with the Late Anisian regional transgressive pulse in the Boreal Ocean.

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Authors and Affiliations

Przemysław Karcz

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