bluuebunny/crossref_metadata_2025 huggingface dataset:
MODELING OF SOLAR RADIATION WITH A NEURAL NETWORK
Authors: STOYANOV VALENTIN , STOYANOV IVAYLO , ILIEV TEODOR
Published: May 2021

Modeling of solar radiation with neural network could be used for real-time calculations of the radiation on tilted surfaces with different orientations. In the artificial neural network (ANN), latitude, day of the year, slope, surface azimuth and average daily radiation on horizontal surface are inputs, and average daily radiation on tilted surface of definite orientation is output. The possible ANN structure, the size of training data set, the number of hidden neurons, and the type of training algorithms were analyzed in order to identify the most appropriate model. The same ANN structure was trained and tested using data generated from the Klein and Theilacker model and long-term measurements. Reasonable accuracy was obtained for all predictions for practical need.
CHEMICAL REAGENTS FOR SELECTIVITY IN IMPROVEMENT OF RHEOLOGICAL PROPERTIES OF CRUDE OIL
Authors: NURULLAYEV VALI HANAQA , USUBALIYEV BEYBALA TACI , GEHREMANOV FIKRET SULEYMAN , GEHREMANOVA ULKER FIKRET
Published: May 2021

Today oil industry – one of the most developing and priority industries of Azerbaijan which plays a huge role in national economy. The need for this mineral constantly increases therefore for improvement of quality and decrease in cost of the product mining companies need to modernize constantly not only the oil-field equipment, but also to improve production processes. Now the increasing number of high-sulphurous and high-paraffinic oil fields is brought into development. As a result, the corrosion rate of the oil-field equipment increases, the output of wells decreases and expenses of mining companies in general raise.
DETERMINATION OF ACETIC AND PROPANOIC ACIDS CONCENTRATION IN NIGERIAN KEROSENE
Authors: ADEGUN ISAAC KAYODE , ADESOYE OLUWATOSIN ADEDAMOLA , IYAGBA ADIO-YUSUF SELIA , ADETORO DAVID ADEBOLA
Published: May 2021

The paper aims to determine acetic and propanoic acid concentrations in some selected samples of kerosene used in Nigeria. The Armfield Liquid-Liquid Extraction Unit was employed to carry out the study. Distilled water and kerosene samples from five different sources were used for the investigation. The parameters taken into consideration during the course of the experiments were time, thermal conductivity, temperature, flow rates and concentration of the acid. It was deduced from the research that the temperature and the conductivity decreased with significant decrease in concentration of the acid and vice versa. The results gotten from the extraction of the kerosene samples also showed that sample A, sample D, and sample E did not contain acetic acid while sample B and sample C had traces of acetic acid, with sample C having traces of propanoic acid. After comparing the values with the standard classification of acetic acid, it was discovered that the concentration of both acetic and propanoic acid in the samples were not significantly sufficient to harm human beings.
MATERIALS FOR AUTOMOTIVE INDUSTRY AND THEIR INFLUENCE ON THE DYNAMICS OF A CAR CRASH
Authors: NAVODARIU NICOLAE , CIOCOIU ROBERT , TRANTE OCTAVIAN , ANTONIAC VASILE IULIAN
Published: May 2021

The aim of this research was to determine the influence of the metallic materials characteristics on the dynamics of a car crash. Another important aspect is that the metallic parts are sometimes repaired after minor accidents and this fact influence strongly the mechanical characteristics and their influence on the dynamics of a car crash. In this paper, we analyze the mechanical characteristics of thin steel plates repaired by local heating associated with plastic deformation (similar to hot working) and cold straightening (similar to local cold working) for automotive side and door panels made of structural steel. Thin sheet plates, 0.9mm thickness, were deformed by impact and repaired by local heating using the flame and induction heating then plastically deformed while hot as well as straightened without heating. The heat repaired samples were studied by light microscopy to determine microstructure change and samples were tensile tested to determine their mechanical characteristics. Local excessive grain growth generates anisotropy, the assembly behaves as a composite material with regions that show significant plastic deformations while others little or no deformations at all. Without procedures adjusted to each material repairs involving heating are to be avoided, cold working should be employed when replacement is not possible.
A STUDY ABOUT THERMAL SIMULATION IN SOLIDWORKS IN THE CASE OF DIFFERENT GEOMETRY OF THE PROCESSED PIECES BY CUTTING
Authors: OLARU IONEL , OLARU CIPRIAN
Published: May 2021

In practice, different cutting processes are encountered, each process having different characteristics. Due to the existing friction forces between the workpiece and the cutting tool, a significant amount of heat is generated. This amount of heat can be determined by experimental measurements. This paper aims to study the way in which the temperature is propagated in the workpiece, so that the phenomenon can be understood and determined how this excessive heat can be removed from the cutting area.
HYDROGENOTUNGSTATO COMPLEXES WITH TIN HALOGENURES (IV): INFRARED AND MÖSSBAUER STUDIES
Authors: DE BARROS DINORA , SEMBENE BOYE MOUHAMADOU , DIOP LIBASSE
Published: May 2021

Six new hydrogenotungstato adducts and complexes have been synthesized and studied by infrared and Mössbauer techniques. The structures are mainly discrete, the anion behaving as a bidentate -one case- or a monodentate ligand in most cases. When extra hydrogen bonds are considered, supramolecular architectures may be obtained.
NEW CHALLENGES IN ABRASIVE WATER JET MACHINING
Authors: CIOFU CATALINA , TAMPU CATALIN , HERGHELEGIU EUGEN , IANCU COSMIN ALEXANDRU , BRABIE GHEORGHE
Published: May 2021

Abrasive water jet machining (AWJM) is one of the most important method used in cutting different types of materials: alloy sheet, marble, glass, rocks. This process is used in the aeronautic, automotive, metallurgy industries and even in some art techniques and textile industry. The method consists in transforming the kinetic energy of a solid particle directed with water jet at a high pressure to remove material through erosion and abrasion. AWJM is low cost equipment compared to other conventional cutting technologies. This paper is an attempt to review the achievements made in AWJM technology for different hardness materials.
STRESS AND DEFORMATIONS IN TOROIDAL SHELLS WITH ELLIPTICAL TRANSVERSAL SECTION
Authors: IATAN RADU , TOMESCU GHEORGHIŢA , DURBACĂ ION
Published: May 2021

The article approaches the analysis of stress and deformation states; in thetoroidal shell with the elliptical cross section with two specific positions, relative to the axisof symmetry. The internal pressure of a working environment as well as the effect of itstemperature are considered external loads. The two effects may overlap taking into accountthe elastic state of the shell material.
OPTIMIZATION OF TURNING PARAMETERS USING AN ALGORTIM BASED ON COMBINED LINEAR AND BINARY SEARCH METHODS
Authors: PRUTICA DAN GEORGE , BRABIE GHEORGHE , CHIRITA BOGDAN
Published: May 2021

Optimization of cutting parameters in machining operations is a complex task requiring extensive knowledge and experience to reach the maximum potential for cost reductions in manufacturing. Through the work presented in this paper a cutting parameters optimization algorithm for roughing and finishing turning has been realized. The proposed optimization algorithm is based on a combination of linear search and binary search methods, heaving as objective criterion the minimization of the machining time. Examples for roughing and finishing turning have been presented to illustrate the application of the proposed algorithm and analyse the results.
ERGONOMIC EVALUATION OF PACKAGING WORKERS’ POSTURE IN A FOOD MANUFACTURING COMPANY
Authors: ISMAILA SALAMI OLASUNKANMI , SALAMI YUSUF ADEYEMI , KUYE SIDIKATU IBIYEMI , DAIRO OLAWALE USMAN , ADEKUNLE NURUDEEN OLATUNDE
Published: May 2021

This study conducted an ergonomic evaluation of the working posture of workers engaged in various processes in the packaging section of a food manufacturing company. Workers in the packaging section of the food manufacturing company were divided into operating, folding, packing, carton wrapping and palletizing. Forty of the workers in the packaging section were placed under observation through video recording of their daily activities for a period of three months to obtain their working postures. Rapid Upper Limb Assessment (RULA) was used to analyze the working postures in order to obtain their ergonomic risk levels. Computer codes for RULA were written for quick and easy evaluation of upper arm, lower arm, wrist, wrist twist, neck, trunk and leg postures. The results from RULA indicated that 25% of the workers in the operating and folding units were exposed to medium ergonomic risk level; 30% of the workers in the packing unit and 10% of the workers in the carton wrapping unit were exposed to high ergonomic risk level while 10% of the workers in the palletizing unit were exposed to a very high ergonomic risk level. The study concluded that workers in the packaging section of the food manufacturing company were exposed to between medium and very high ergonomic risk levels of working posture necessitating the need to change the conditions of their workstations.
A CFD ANALYSIS IN SOLIDWORKS FLOW SIMULATION FOR TWO MIXING FLUIDS WITH DIFFERENT TEMPERATURES IN NOZZLES
Authors: OLARU IONEL
Published: May 2021

The heat can have a direct impact on the mechanical elements by creating deformations and by causing the induction of additional stress in them. In designing of the heat exchangers or for the electronic components, the temperature changes for structural analysis as well as structural performance of thermal impact for the entire element must be analyzed. The study from this paper proposes an analysis and a simulation of flow through the convergent-divergent nozzle type to optimize the inlet of warm fluid to have minimum impact on the nozzle walls This analysis will be performed with a computer program specialized in complex analysis of Computational Fluid Dynamics (CFD), which will also take into account the fluid temperature and its influence throughout the system.
REAL TIME ASSESSMENT OF 500-KVA, 11/0.415 KV DISTRIBUTION TRANSFORMER SITUATED AT BELLS UNIVERSITY OF TECHNOLOGY, OTA, OGUN STATE USING FLUKE 435 SERIES II
Authors: AMOLE ABRAHAM OLATIDE , OKUSAGA KAZIM IDOWU , ODEKUNLE OLUFEMI OLANREWAJU , ODITA IKECHUKWU JOSEPH
Published: May 2021

Distribution transformer being major equipment in utility companies deserves to be routinely scrutinized for its performance with a view to ensure continuous supply of energy to end-users as well as to sustain improved revenue collection by the utility company. Presented in this paper is the real time assessment of 500-kVA, 11/0.415 kV distribution transformer situated at Bells University of Technology, Ota, Ogun State using power quality and energy analyzer equipment. The parameters measured on real time include phase to neutral voltage, phase to phase voltage, root mean square and peak current, frequency, active power, reactive and apparent power and line power factor. The assessment revealed wide variation of system voltages far from the standard, however, the line power factor and as well as frequency of operation was observed to be within the standard. Based on this analysis, several findings and appropriate recommendations were suggested to improve the supply of energy in the study area. It is hope that the findings of this research will be of immense benefit to distribution engineers at the Department of works in Bells University of Technology, Ota for field compliance.
CONSULTATION OF WORKERS AS A MEASURE FOR IMPROVEMENT THE OH&S MANAGEMENT SYSTEM. CASE STUDY AT THE „VASILE ALECSANDRI” UNIVERSITY OF BACAU
Authors: RADU MARIA-CRINA
Published: May 2021

Identifying and assessing occupational health and safety risks and implementing measures to prevent accidents at work and occupational diseases are legal obligations and the implementation and certification of an occupational health and safety (OH&S) management system may help organization to achieve these goals, being also a credible evidence of its commitment to protect life and health of its interested parties. Consultation and participation of workers at all applicable levels and functions is part of the system; workers involved in daily activities and those most at risk can provide a broad perspective on potential problems and the decisions made with these workers are likely to be more effective for system improvement. The paper presents the results of a study on consulting workers of the "Vasile Alecsandri" University of Bacau on occupational health and safety issues.
SUPPORTING THE TRANSITION FROM SCHOOL TO ACTIVE LIFE. CASE STUDY: FEEDBACK ANALYSIS OF THE INTERNSHIPS STUDENTS OF „VASILE ALECSANDRI” UNIVERSITY OF BACAU
Authors: RADU MARIA-CRINA , SAVIN PETRONELA , NEDEFF VALENTIN , GRIGORE ROXANA
Published: May 2021

At all stages of life, education and training are essential aspects of human development and key factors for economic growth, jobs, and social cohesion. High quality and inclusive training must be a main goal of our society, especially as we live in a very challenging period, governed by the fourth industrial revolution, that transforms economies, jobs, and the society itself. Because of this, the „Vasile Alecsandri” University of Bacau is involved as a partner, with other universities, in a project with European funding, that facilitates practical training of students at economic partners, to increase the employability of graduates and obtain feedback from employers to correlate the curriculum to the labor market. The current paper aims to present a case study related to the feedback offered by the students who carried-out internships at local economic agents, within the above-mentioned project.
CRYSTAL STRUCTURES OF TWO PHOSPHONATE SALTS: MONOCYCLOHEXYLAMMONIUM HYDROGEN PHOSPHONATE AND MONOCYCLOHEXYLAMMONIUM PHENYL PHOSPHONATE
Authors: SARR MODOU , DIOP MOUHAMADOU BIRAME , BOYE MOUHAMADOU SEMBENE , DIASSE-SARR AMINATA , GUIONNEAU PHILIPPE
Published: May 2021

Hydrogen phosphonate anions and monocyclohexylammonium cations interacting through hydrogen bonds conduct to the formation of a salt namely monocyclohexylammonium hydrogen phosphonate. In this structure, hydrogen phosphonate anions are linked by pairs through O—H···O hydrogen bonds leading to anionic dimers. Each dimer is connected to its two neighbours through cations via N—H···O hydrogen bonds leading to infinite chains which are then connected by N—H···O hydrogen bonds giving rise to a layered structure. The phenyl phosphonates form dimers that are connected through an expended hydrogen bonding network involving the cations into a layer.
OPTIMIZATION OF OIL EXTRACTION FROM GARCINIA KOLA USING ARTIFICIAL NEURAL NETWORK AND RESPONSE SURFACE METHODOLOGY
Authors: UWADIAE SYLVESTER , OVIESU FAITH , AYODELE BAMIDELE
Published: May 2021

The target of this investigation was to model and optimize selected process parameters when extracting oil from Garcinia kola. Artificial neural network (ANN) and Box-Behnken design (BBD) in response surface methodology (RSM) were used for the modelling and optimization of the process parameters. The optimized process values were 397.86 mL and 399.99 mL for solvent volume; 109.32 min and 107.55 min for extraction time; 72.64 g and 70 g for sample mass and maximum yields of 20.839 wt% and 20.488 wt% for RSM and ANN respectively. The highly positively correlated experimental and anticipated values validated the models.
INTERACTIONS BETWEEN CETYLTRIMETHYLAMMONIUM OR TETRAMETYLAMMMONIUM BROMIDE AND MCl2 OR MCl5 (M = Hg, Cu, Zn, Co, Ni, Cd and Nb) IN MONONUCLEAR COMPLEXES: SYNTHESIS AND INFRARED STUDY
Authors: SEYE DAME , TOURE ASSANE , DIOP CHEIKH ABDOUL KHADIR , DIOP LIBASSE
Published: May 2021

On allowing cetyltrimethyl ammonium bromide (C19H42NBr) and HgCl2, CuCl2.2H2O, CoCl2.6H2O, ZnCl2, NiCl2.6H2O or NbCl5 in specific ratio in methanol, new mononuclear have been obtained and studied by infrared. The suggested structures are discrete, of infinite chain with octahedral or tetrahedral environments around the metallic centres. The MX2 behaves as discrete chains. For most of the structures, when intermolecular hydrogen bonds are considered, supramolecular architectures may be obtained.
ANALYSIS OF DOWNTIME IN A TYPICAL NIGERIAN MULTINATIONAL BOTTLING COMPANY
Authors: JOEL ABAFI , ADEKOLA OKE
Published: May 2021

Failure data were extracted from the report book of the case study company. These data were stratified and analysed.Data stratification was pivotal in the separation of failure data into smaller and more defined form based on a predetermined set of criteria. Filler system was found to have the highest percentage failure occurrences; hence a standby filler system became the best option. The study concluded that, although in a production/manufacturing system, downtime is inevitable but it can be limited to the planned downtime with respect to the typical Nigerian multinational bottling company.
ASSESSMENT OF EFFICIENCY OF COMPOST PREPARED FROM ANIMAL WASTE IN THE REDUCTION OF TOTAL PETROLEUM HYDROCARBON IN CRUDE OIL IMPACTED SOIL
Authors: ADEKUNLE ADEBOLA , ADEKUNLE IHEOMA , AROGUNDADE SUHAIB
Published: May 2021

The aim of this study was to investigate the potentials of composted animal waste in biodegradation of hydrocarbon in a cost-effective, efficient, and environmental-friendly manner. The contaminated soil sample was collected from Ojoo area in Ibadan, Oyo state, Nigeria. Two different types of compost – sheep-waste-sawdust (SPW-SD) and goat-waste-sawdust (GTW-SD) were applied to a soil at a rate (0 g, 750 g, 450 g). The result depicted that the contaminated soil experienced an enhanced natural bioremediation due to the applied bioremediation agents and the contaminated soil treated with SPW-SD gave best results. Samples remediated with SPW-SD and GTW-SD showed a Total Petroleum Hydrocarbon (TPH) removal efficiency of 55.4% and 7.9% respectively. Analysis showed that oil type, compost rate and period of application influenced the bioremediation process. From the results, composted organic waste application is a good and efficient way of remediating hydrocarbon impacted soil.
PERFORMANCE EVALUATION OF ETHERNET TRANSMISSION USING M-ARY PULSE AMPLITUDE MODULATION TECHNIQUES
Authors: OLALEKAN APENA WALIU , GRACE OLASUNKANMI OMOWUMI , ANUOLUWAPO SALAKO
Published: May 2021

Low installation costs and high data rates reaching up to 10 Gbps, characterized Ethernet as the local area network (LAN) technology of choice to satisfy the increasing need for high-speed data transmission in packet-based networks. As demand for high speeds in data has increased, copper Ethernet has been integrated to handle these higher speeds. The IEEE 802.3ae* 2002 (10 Gigabit Ethernet) standard is based on data transmission over optical fibre only and in full-duplex mode. This study considered performance evaluation of Pulse Amplitude Modulation (PAM) and multilevel (PAM-16) technology in comparison with other PAM versions was carried out to investigate copper Ethernet with respect to higher speed characteristic and error performance. The evaluation was carried out in MATLAB R2017b simulation environment; this provides calculated bit error rates (BER) of the considered modulation schemes under different channel conditions. The results show that PAM-16 has a BER of .which is significantly lower than that of PAM-2 and PAM-4. Additionally, Hamming code were used to detect and correct errors that are inherent in the design and the efficiency of each level of PAM used was analyzed.
Immunophenotypic aberrancy in acute leukemia – a retrospective single institute study
Authors: Asghari Ehsan , Radfar Seyedeh Niayesh , Nematollahi Pardis
Published: May 2021

Introduction:
In 2016, WHO gave a comprehensive classification system that included morphology, immunophenotyping, molecular and genetic findings. Flow cytometric immunophenotyping is the backbone of WHO classification, helping to make a more accurate and faster diagnosis.

Aim:
This study has been conducted to find immunophenotyping aberrancy of acute leukemia (AL) and its association with gender and age group.

Material and methods:
This is a descriptive retrospective study of 1012 AL patients diagnosed between January 2011 and January 2019, including all new patients of all ages and both sexes, who had available immunophenotyping data.

Results and discussion:
The most common aberrant antigen on acute myeloid leukemia (AML) was CD7, on precursor B lymphoblastic leukemia (B-ALL) was CD33 and on precursor T lymphoblastic leukemia (T-ALL) was CD13. There was no association between sex/age and antigen aberrancy except a significant increase in CD34 loss on pre B acute lymphoblastic leukemia (pre B-ALL) and HLA-DR expression on acute promyelocytic leukemia (APL) in males compared to female patients and an increase of CD19 expression on non-APL-AML and an elevation of CD34 loss on T-ALL in adult compared to pediatric patients. Not only detection of aberrant expression of CD markers in leukemic cells helps to estimate molecular abnormalities and has a prognostic effect, but also a specification of neoplastic cell markers at the time of diagnosis is essential for monitoring patients after treatment.

Conclusions:
Although in this study, no association between sex/age and aberrancy of antigens was detected (except in certain AL subtypes), AL specific immunophenotype is essential for minimal residual disease detection.
Impact of Heavy Metals on Development of Metal Resistance in Soil Microbiota
Authors: TIMKOVÁ Ivana , PEVNÁ Viktória , PRISTAŠ Peter , SEDLÁKOVÁ-KADUKOVÁ Jana
Published: May 2021

Heavy metal pollution caused by anthropogenic activity is a great concern of the present days. Widespread use of substances containingmetals inevitably lead to their deposition in soil affecting soil microbiota, which plays important role in maintaining soilfunctions. The aim of our study was to determine number of heavy metal resistant isolates acquired from the soil from heavy metalpolluted area of dump near Hnúšťa. Soil samples were obtained from two collection sites (48° 36´ 4,47502´´ N, 19° 57´32,654´´ Eand 48° 36´ 4,4634´´ N, 19° 57´ 32,67´´ E) and mixed together. The microorganisms used in this study were routinely cultivatedand screened for resistance to different concentrations of four heavy metals – Zn (2–500 mg/l), Cu, Ni, Pb (all three metals testedat concentrations from 0,5 to 125 mg/l). Very high resistance against Cu, Ni and Pb even at the highest tested concentrations wasfound at majority of tested bacterial strains. Almost all 89 from 89 isolates show resistance against these metals at tested concentrations.Only in case of Zn we determined the MIC (minimal inhibitory concentration) – 125 mg/l. The results point out very highresistance pattern in soil bacteria.
The Experimental Estimation of The Elastic Modulus of a Fly Ash Based Trackbed Layer Under Cyclic Loading
Authors: LOJDA Vít , LIDMILA Martin , PÝCHA Marek
Published: May 2021

In a railway track structure system, trackbed layers are designed to compensate for insufficient bearing capacity and/or water orfrost resistance of natural soil. These, so called, ‘capping layers’ can be constructed from raw materials like sand or gravel or fromindustrial materials like asphalt or concrete. However, more environmentally and cost friendly alternatives have been studied in recentyears. Fly-ash represents one such promising material and a trial section of a main line track with the capping layer made froma fly-ash-based mixture was constructed in Czech Republic in 2005. The performance of the capping layer in the section has beenmeasured since. In this paper, results of the laboratory estimation of the elastic modulus under cyclic traffic-like induced loading arepresented for the most recent group of samples. The results show that the elastic limit of the fly-ash-based material lies well abovethe stresses induced by railway traffic and that its behaviour is stable under the cyclic loading. This suggests that the mechanicalproperties of the material may not be determinative for the design of the layer and that the feasibility factors may take precedent.This in turn suggests that either the design strength of the material or the designed thickness of the layer may be possibly reduced.
Distribution of Antimony and Gold in Old Tailings and Heaps at the Milešov Locality (Příbram District)
Authors: ŠTRUPL Vít , STANĚK František , RAUS Miroslav
Published: May 2021

Antimony ores were extracted and processed near the village of Milešov (Příbram district) for about twenty years in the second halfof the 19th century. Large heaps and a small sludge pond were left behind after this period. In 1988, this locality was inspected andsampled in order to gather information about residual resources of gold and antimony. The original archive data from this surveywere now studied again and interpreted using modern statistical and geostatistical methods. The interpolations methods chosenfor this purpose were inverse distance weighting (IDW), simple kriging and geostatistical sequential Gaussian simulation (SGS).These procedures allowed for a much more accurate determination of the spatial distribution of the elements or substances studied.The results showed significantly higher volumes and a more accurate localization of the studied elements in both bodies (heap andtailings). This procedure can be considered as the basis of a new methodology for the assessment of similar objects.
A liturgia das horas, caminho de santidade
Authors: Beckhäuser Alberto
Published: May 2021

Em 1971 era publicada a Liturgia das Horas renovada segundo a mente do Concílio Vaticano II. Agora, finalmente, depois de muitas vicissitudes, temos o Officium Divinum, a Liturgia das Horas, em quatro volumes, na sua versão portuguesa para o Brasil em nossas mãos. A demora talvez tenha sido até providencial, pois a temos já em sua segunda edição típica original publicada entre os anos 1985 e 1987...
Deus da vida e ídolo da morte na nova economia mundial
Authors: Sung Jung Mo
Published: May 2021

A nova sociedade que está sendo gestada não difere qualitativamente do capitalismo, isto é, não chega a ser verdadeiramente uma sociedade “pós-capitalista”...
Predicting Tensile Strength Growth From Self Compacting Concrete Partially Replaced Cement with Wood and Fly Ash
Authors: S.N. Eluozo , K Dimkpa
Published: May 2021

This paper monitors the growth rate of tensile strength under partial replacement of locally sourced materials, the study monitor the behaviour of tensile between seven and  twenty eight days of optimum curing age,  modeling and simulation were applied in the study, whereby parameters that generate the attained tensile strength from self compacting concrete were monitored considering various factors such as variation of compaction and water cement ratio, the reaction of these parameters were examined in the study through the simulation, the reflection of these parameters influence where observed in all the trend, the study examined the level of significances of tensile on concrete structure, therefore try to evaluate  various reflection effect from permeability and other parameters that were not considered in  experimental process, these are  developed from  self compacting concrete partially replace cement with fly ash and wood.  Tensile strength is an important property of concrete due its level of vulnerability to tensile cracking base on different kind of applied loading itself. The influence of permeability as a physical property has definitely affect the durability of concrete, these  where observed on the its reflection on tensile strength in all the trend, the rate of permeability effect on tensile were monitored to reflect its reaction through microstructural perspective influence from porosity, pore size, connectivity including its rates of bonding, these correlation includes  air content and capillarity, there rate of permeability coefficient on its reduction are determined by the decrease in porosity and void ratios from concrete compaction rate, it is  reflected on  its variation  of tensile strength in self compacting concrete, the rate of permeability reducing at constant rates determined the tensile strength through it microstructural  setting on the self compacting concrete, these condition were applied on the simulation to generates the predictive values compared with experimental values by an expert [22], while an improvement were made on it study, these include monitoring of concrete permeability and void ratios effect on tensile, the behaviour of porosity under the influence of permeability and variation concrete void were examined from the permeability influence on tensile strength.
Non-fragile Dynamic Output Feedback H∞ Control for a Class of Uncertain Switched Systems with Time-varying Delay
Authors: Song Yuning , Liu Yuzhong
Published: May 2021

The problem of non-fragile dynamic output feedback H∞ control for a class of uncertain switched systems with time-varying delay is discussed. Firstly, the form of non-fragile dynamic output feedback H∞ controller is given. Under the condition that the upper bound of time delay and the upper bound of delay derivative are limited simultaneously, Lyapunov functional and its corresponding switching rules are constructed by using single Lyapunov function method and convex combination technique; Secondly, we use the inequality lemma to scale the derived Lyapunov functional in order to eliminate the time-varying delay term in the inequality, and then introduce the J-function to obtain a nonlinear matrix inequality that satisfies the H∞ performance index γ, we also employ Schur complement lemma to transform the nonlinear matrix inequality into set of linear matrix inequalities consisting of two linear matrix inequalities, a sufficient condition for the existence of a non-fragile dynamic output feedback H∞ controller and satisfying the H∞ performance index γ is concluded for a class of uncertain switching systems with variable time delay; Finally, a switched system composed of two subsystems is considered and the effectiveness and practicability of the theorem are illustrated by numerical simulation with LMI toolbox.
Footprint of Arsenic Contamination in Sediments and Water from Mining Sites – A case study based on multivariate optimization by GF AAS
Authors: De Filippis Glenda , Costa Bruno , Borges Simone , Borges Neto Waldomiro , Coelho Nivia Maria , Coelho Luciana
Published: May 2021

Arsenic contamination is worrisome in mineral exploration regions. Efficient arsenic monitoring is dependent on detectability at trace level in environmental matrices. This paper presents a procedure to evaluate the occurrence of arsenic in environmental sediment and water samples collected from a mining area in Catalão, Goiás State (GO), Brazil. The water and sediment samples were analyzed by graphite furnace atomic absorption spectrometry (GF AAS) after appropriate chemical treatment. For the arsenic determination, analytical performance was improved employing multivariate tools. The instrumental conditions were optimized using a 23 factorial design and the response surface methodology (RSM) was applied with a central composite design (CCD). Iridium was used as a permanent modifier. The results for the sediment samples showed arsenic concentrations below the threshold for adverse effects ranging from 2.06 to 3.82 mg Kg-1. The concentrations in water samples were below LOD. The LOD and LOQ were, respectively, 0.33 and 1.09 µg L-1 to water and digested sediment samples. Under the optimal conditions, the dynamic working range was linear of LOQ to 50.0 µg L-1. The method was applied to determine concentrations of arsenic in water and sediments collected from mining sites, which can be used to assess the availability of arsenic in the region.
21. Yüzyıl Yaz Olimpiyat Oyunlarında Teknoloji Kullanımı Üzerine Bir İnceleme
Authors: DÖNMEZ Emre , KAYA Emine , YILDIZ Kadir
Published: May 2021

Bu araştırmada 21. Yüzyıl Yaz Olimpiyat Oyunlarında kullanılan teknolojilerin incelenmesi amaçlanmıştır. Çalışma da nitel araştırma yöntemlerinden durum çalışması deseni kullanılmıştır. Verilerin analizi sürecinde ise doküman analizi yöntemi kullanılmıştır. Uluslararası Olimpiyat Komitesi’nin (IOC) 2000-2020 yılları arasında düzenlemiş olduğu Sidney 2000, Atina 2004, Pekin 2008, Londra 2012 ve Rio 2016 Yaz Olimpiyat Oyunlarının resmi olimpiyat raporları analiz edilerek araştırmanın amacına uygun doküman sağlanmaya çalışılmıştır. İnceleme sonucunda; Sidney 2000 Yaz Olimpiyat Oyunları düzenlendiği tarih itibariyle, teknolojinin henüz yeni yeni gelişmeye başladığı bir dönem olarak karşımıza çıkmaktadır. Atina 2004 Yaz Olimpiyat Oyunlarındaki teknoloji kullanımını bilgi teknolojisi, telekomünikasyon, enerji ve mekân teknolojisi bölümleri kapsamında incelenmiştir ve Sidney 2000 Yaz Olimpiyat Oyunları’na kıyasla fark edilir bir artış olduğu görülmektedir. Pekin 2008 Yaz Olimpiyat Oyunlarıyla birlikte ‘Yüksek Teknoloji Olimpiyatları’ kavramı karşımıza çıkmaktadır. Pekin 2008 Yaz Olimpiyat Oyunları Ana Basın Merkezi, Olimpiyat Oyunları tarihindeki türünün en büyük örneği olmuştur. Londra 2012 ve Rio 2016 Yaz Olimpiyat Oyunlarından sonra teknoloji kullanımının hızla arttığı ve kullanılan teknolojik aletlerin çeşitlendiği görülmektedir.
MORPHOGRAPHIC STUDY OF BOIULUI VALLEY HYDROGRAPHIC BASIN
Authors:   Ph.D. candidate, University of Oradea, Department of Geography, Tourism and Territorial Planning, University St., 410087, Oradea, Romania, GARAI Lavinia Daiana
Published: May 2021

The aim of the present paper is to determine the morphometric parameters and features of Boiului Valley hydrographic basin. The basin is located in a karst area, in Pădurea Craiului Mountains, Romania, which makes it special, as the rivers flow through soluble rocks. We selected a small basin in order to analyse its morphometric elements and check if the morphometric laws of hydrographic basins are respected in the same way by the rivers flowing in karst areas. We applied the classical working method, that is processing the information from the topographic maps and with the help of the ArcGis soft we managed to measure the major morphometric indicators: the surface of the basin, the area, the shape factor, the length and width of the basin, drainage basin asymmetry factor and sinuosity index.
NUANCED GENDER PERCEPTIONS: TOURISM BUSINESS CAPABILITIES IN KWAZULU-NATAL, SOUTH AFRICA
Authors:   University of Zululand, Department of Recreation and Tourism, KwaDlangezwa 3886, South Africa, NZAMA Nompumelelo , EZEUDUJI Ikechukwu O. ,   University of Zululand, Department of Recreation and Tourism KwaDlangezwa 3886, South Africa
Published: May 2021

We explored nuanced gender perceptions regarding the influences that business capabilities may have on tourism-related business operations in Durban, KwaZulu-Natal. We used structured questionnaire to collect data from 150 tourism-related entrepreneurs and managers. This study made no conclusive finding that gender does play a role with regard to differentiating business success or performance, as reported in some literature. However, marketing capability is the main factor that influence business performance.
Physical education and sports for the physically disabled in terms of body sociology
Authors:   Ministry of Education, Manisa, Turkey, Afacan Ersin
Published: May 2021

Body sociology is a branch of sociology that studies the human body's relationship with the factors that make up society. It also investigates the position of disabled individuals in society. Because according to the sociology of the body, the body is a phenomenon that has a meaning in society. Therefore, the dynamics, norms and values of the society directly affect people's body perception. This study aims to explain the importance of physical education and sports for disabled people according to the basic principles and theories of physical education sociology. For this study, data compiled from different sources in sports and sociology related to the subject of physical education and disabilities were collated. Therefore, the study's limitation conducted using the analytical method is that it is a compilation study conducted in a theoretical framework.
The effect of the imagination levels of the faculty of sports sciences students on mental toughness
Authors:   Spor Bilimleri Fakültesi, Karamanoğulu Mehmetbey Üniversitesi, Karaman, Türkiye, Ali Uğur Oruç
Published: May 2021

The aim of this study is to evaluate the effect of the imagination levels of the students of the faculty of sports sciences on mental toughness. The demographic form containing personal information, the Sports Imagination Scale developed by Hall et al. (1998) and the scale adapted to Turkish by Vurgun (2010), reliability and validity study of which was carried out, were used to collect the data. It can be said that the imagination characteristics of the participants are at a good level and their mental toughness characteristics are close to the middle level. It was found that the imagination and mental toughness of the participants did not differ according to the gender variable. The imagination levels of the participants who are interested in team sports and who are engaged in individual sports do not differ significantly. When we look at the results obtained within the scope of correlation analysis in the study, it was found that there is a moderate and positive relationship between imagination and mental toughness. As a result of the regression analysis, it was found that imagination in sports has a significant positive contribution in explaining its effect on mental toughness. It can be said that the higher the level of imagination in sports, the higher the mental toughness.
Who Studied at the Beit Midrash?: Funding Palestinian Amoraic Education
Authors: Marks Susan
Published: May 2021

The house of study of Amoraic Palestine has resisted study because of its informality. By situating it alongside Hellenistic, Roman and Christian education, this article argues that examining their funding provides a means of understanding the structural tendencies of these study circles. Communal support appears mostly aspirational, providing clues as to intention and conflicts regarding inclusion. Similarly, narratives concerning individual gifts urge their moral good rather than their reliability, thus pointing inevitably to fees as the underlying means of support for the beit midrash. The necessity of fees in turn demands consideration of how those of more marginal means, including scribes, could afford this tuition. Finally, that teaching younger children provided one avenue of such support reveals a complex interdependency of those who had easier access to this education and those who had less access, as well as the barely glimpsed suggestion of other educational alternatives.
Bile in excess
Authors: Gubergrits N. B. , Agibalov O. M.
Published: May 2021

The article presents consideration for the pathogenetic mechanisms of the occurrence of duodenogastric reflux (DGR), duodenogastroesophageal reflux (DGER), their role in the occurrence of biliary reflux gastritis and reflux esophagitis. The fundamental bases for the formation of bile reflux are the failure of the sphincter apparatus, antroduodenal dysmotility, elimination of the natural antireflux barrier. Gallbladder dysfunction and duodenal dysmotility are considered the risk factors for primary DGR. The leading mechanism for the development of DGR, DGER after cholecystectomy is a violation of gastroduodenal motility and gastroduodenal hypertension. These syndromes are formed also at gallstone disease and other organic and functional pathological conditions, including pancreatic insufficiency. The syndrome of chronic duodenal hypertension or «duodenal demon» is manifested by heaviness in the epigastrium, belching, heartburn, nausea, vomiting, flatulence, and stool disorders. It is supplemented by the phenomena of psychosomatic asthenization, decreased mental and physical performance, apathy, and a negative assessment of life prospects. The clinical features of hologenous diarrhea are considered, differential diagnostic signs of diarrhea in chronic duodenal hypertension and irritable bowel syndrome are demonstrated.The clinical and pathogenetic substantiation of the treatment of chronic duodenal hypertension accompanied by hologenous diarrhea with colloidal bismuth preparations is presented. The summary of the comparative analysis has been presented of the physicochemical and structural properties of tablet formulations, containing bismuth tripotassium subcitrate, the original drug De‑Nol (Astellas) and the generic Ulcavis (KRKA). It has been concluded that it is advisable to include Ulcavis in the treatment regimen for patients with hologenous diarrhea.
Short-chain fatty acids: role in metabolic disorders
Authors: Fadieienko G. D. , Gridnev O. E.
Published: May 2021

The article presents research data on the role of short‑chain fatty acids in the pathogenetic mechanisms of the development of metabolic disorders. The brief description of the main short‑chain fatty acids — acetate, butyrate and propionate and the connection of their production with bacterial strains of the intestinal microbiome is given. The data on changes in the level of acetate, butyrate and propionate in feces and blood depending on body weight in animals and humans are presented. The mechanism of using by these fatty acids of such signaling pathways as interaction with receptors of fatty acids 2 and 3, inhibition of histone deacetylases to influence various metabolic processes and energy metabolism is described in detail. Their interaction on GLP‑1 and YY peptide as a result of interaction with enteroendocrine L‑cells of the intestine is described separately, which has an effect on appetite and, accordingly, food intake. The effect of basic short‑chain fatty acids on intestinal permeability is also described, which is important for the increased penetration of lipopolysaccharides of gram‑negative bacteria from the intestine into the bloodstream. The most important role of short‑chain fatty acids in the development of inflammatory processes, including low grade inflammation characteristic of metabolically associated diseases is indicated. The data of studies describing the study of the role of acetate, butyrate and propionate in non‑alcoholic fatty liver disease, type 2 diabetes mellitus, arterial hypertension, atherosclerosis and endothelial dysfunction are presented. The results of studies both in animals and in humans on the use of direct administration of acetate, butyrate and propionate and factors that enhance their production to influence metabolic and inflammatory processes are also described.
Penggunaan Media Box of Number and Alfabeth untuk Meningkatkan Kemampuan Kognitf, Bahasa dalam Mengenal Angka, dan Abjad
Authors: Ulfadhilah Khairunnisa , Suyadi Suyadi
Published: May 2021

Media berfungsi penting untuk menggapai suatu pencapaian belajar sebab dapat memudahkan bagi pendidk disekolah untuk menjelaskan bahan ajar untuk pembelajaran, dan adanya media guna anak didik mampu menerima pembelajaran serta media memudahkan pendidik dalam memberikan stimulasi. Metode yang peneliti gunakan adalah kualitatif deskriprtif. Teknik pengumpulan data pada riset telah dilaksanakan merupakan observasi, wawancara, dan dokumentasi. Hasil penelitian dengan menerapkan langsung cara dalam pelaksanaan pengunaan media box of number, and alfabeth: 1) Guru meletakkan media of box number and alfabeth di depan, lalu menjejerkan kepingan-kepingan angka, dan huruf. 2) Guru mempersilahkan anak untuk mengambil kepingan-kepingan angka, dan huruf lalu memasukka sesuai tempat angka beserta huruf tersebut. 3) Setelah itu anak mengambil kepingan tersebut lalu menunjukkan ke guru beserta teman sebaya nya dikelas
Peningkatan Kemampuan Kognitif Anak Usia Dini melalui Media Pembelajaran Beam Number dari Kardus Bekas
Authors: Nurlaela Nurlaela , Suyadi Suyadi
Published: May 2021

Masa pra sekolah merupakan tahapan yang sangat berarti dalam kehidupan seseorang, yang sangat mempengaruhi tahap perkembangan selanjutnya maka diperlukan perhatian lebih pada aspek-aspek perkembangan yang ada. Aspek perkembangan kognitif adalah aspek yang penting dikembangkan secara maksimal. Pengembangan aspek kognitif salah satunya dapat dilakukan melalui media beam number. Tujuan Penelitian ini guna untuk mengetahui penerapan atau pelaksanaan media beam number dalam kemampuan mengenal angka 1-10 untuk anak usia 4-5 tahun. Metode yang digunakandalam penelitian ini menggunakan metode jenis Penelitian Tindakan Kelas model Kemmis dan McTaggart. Dalam pengamatan ini peneliti mengumpulkan data melalui observasi, wawancara,, dan dokumentasi, dan pengamatan tersebut menggunakan analisis deskriftif kuantitatif. Peneliti melalukan pengamatan sebanyak 8 kali. Pengamatan tersebut menghasilkan bahwa peningkatan mengenal angka untuk anak kelompok A adanya peningkatan pada pra siklus sebesar 29,5%, kemudian pada siklus 1 terjadi kemajuan sebesar 65%, dan siklus II meningkat sebesar 100%. Media beam number adalah salah satu media alternatif untuk mengenal angka usia 4-5 tahun
Deskripsi Tahapan Problem Solving Siswa Pada Soal Bertipe Pisa Space and Shape Content
Authors: Maharani Rasendriya Adinda , Aini Indrie Noor
Published: May 2021

Rendahnya hasil PISA yang berarti rendahnya problem solving siswa terutama pada space and shape content. Terdapat beberapa faktor penyebab salah satunya siswa tidak cukup kompeten dalam menyelesaikan soal-soal bertipe PISA. Sehingga penelitian ini bermaksud untuk mendeskripsikan tahapan problem solving siswa jika diberikan soal bertipe PISA terutama pada space and shape content disalah satu Lembaga Kursus Matematika Jakarta Timur. Waktu penelitian ini dilaksanakan pada bulan April. Jenis penelitian yang diambil yaitu penelitian kualitatif dengan metode analisis deskriptif. Instrumen yang digunakan berupa adopsi 1 soal PISA dengan space and shape content. Subjek penelitian terdiri dari 20 siswa dengan kriteria siswa yang berumur 15 tahun yang masing-masing memiliki kemampuan tinggi, sedang dan rendah. Data dianalisis dengan cara memberikan skor pada setiap jawaban subjek, lalu skor tersebut dirubah kedalam nilai persentase. Hasil penelitian menunjukkan siswa dengan kemampuan kategori tinggi sudah mencapai tahapan problem solving sebesar 100%, siswa dengan kemampuan kategori sedang mencapai tahapan problem solving sebesar 50% dan siswa dengan kemampuan kategori rendah mencapai tahapan problem solving sebesar 25%. Berdasarkan data tersebut siswa dengan kemampuan kategori sedang dan kategori rendah belum maksimal dalam memenuhi tahapan problem solving.
Pengaruh Model Pembelajaran Reciprocal Teaching Berbantuan Google Meeting Terhadap Kemampuan Komunikasi Matematis Peserta Didik SMP Pada Masa Pandemi Covid-19
Authors: Astuti Niken Dwi , Purwanto Sigid Edy
Published: May 2021

Penelitian ini bertujuan untuk mengetahui pengaruh model pembelajaran reciprocal teaching berbantuan google meeting terhadap kemampuan komunikasi matematis smp pada masa pandemi covid-19. Penelitian ini dilatarbelakangi oleh hasil penelitian-penelitian terdahulu yang menunjukkan bahwa kemampuan komunikasi matematis peserta didik belum sesuai dengan yang diharapkan. Penelitian ini menggunakan metode kuantitatif yang menerapkan dua pembelajaran yaitu pembelajaran dengan model reciprocal teaching dan pembelajaran konvensional. Subjek yang digunakan dalam penelitian ini adalah siswa kelas VII-4 sebanyak 40 siswa dan VII-5 sebanyak 41 siswa di SMP Negeri 5 Cibitung. Jenis instrumen yang digunakan dalam penelitian yaitu tes uraian. Tes uraian digunakan untuk mengetahui kemampuan komunikasi matematis siswa yang diberikan sesuai dengan kurikulum yang berjalan. Pada uji kelompok eksperimen diperoleh rata-rata(mean) sebesar 69,878 dan serta . Dengan besar pengaruh menggunakan perhitung effect size sebesar 0,41. Sehingga hasil penelitian menyimpulkan bahwa “Terdapat pengaruh model reciprocal teaching berbantuan google meeting terhadap kemampuan komunikasi matematis pada masa pandemi covid-19”.