Search results for: moisture determination
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2767

Search results for: moisture determination

1447 Determination of Natural Gamma Radioactivity in Sand along the Black Sea Coastal Region of Giresun, North Turkey

Authors: A. Karadeniz, Belgin Kucukomeroglu

Abstract:

In this study natural gamma radioactivity levels are determined on sands along the coastal regions of Giresun/Turkey. The coast of Giresun about 290 km long in investigated to collect 101 sand samples. Natural and artificial radioactivity concentrations of sand samples were measured by using HPGe gamma spectrometry. The average activity concentrations of 238U, 232Th, 40K and 137Cs on sand samples of Giresun were found to be 10.83±2.92 Bq/kg, 21.28±3.22 Bq/kg, 6.42±1.06 Bq/kg, 230.94±10.67 Bq/kg respectively. The average activity concentrations for these radionuclides were compared with the reported data of other parts of Turkey and other countries. The average absorbed dose rate for Giresun was calculated to be 38.68 nGy/h respectively. This value is significantly lower than the World averaged value of 60 nGy/h. The external annual effective dose rate concentration in Giresun was found to be 0.047 mSv/y respectively. This result is much lower than the recommeded limit of 5 mSv/y. The external hazard dose rate for Giresun weas calculated to be 0.21 respectively. This result is much lower than the recommended limit of 1.0.

Keywords: concentration, radioactivity, Giresun, natural gamma radioactivity

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1446 Effect of Treated Peat Soil on the Plasticity Index and Hardening Time

Authors: Siti Nur Aida Mario, Farah Hafifee Ahmad, Rudy Tawie

Abstract:

Soil Stabilization has been widely implemented in the construction industry nowadays. Peat soil is well known as one of the most problematic soil among the engineers. The procedures need to take into account both physical and engineering properties of the stabilized peat soil. This paper presents a result of plasticity index and hardening of treated peat soil with various dosage of additives. In order to determine plasticity of the treated peat soil, atterberg limit test which comprises plastic limit and liquid limit test has been conducted. Determination of liquid limit in this experimental study is by using cone penetrometer. Vicat testing apparatus has been used in the hardening test which the penetration of the plunger is recorded every one hour for 24 hours. The results show that the plasticity index of peat soil stabilized with 80% FAAC and 20% OPC has the lowest plasticity index and recorded the fastest initial setting time. The significant of this study is to promote greener solution for future soil stabilization industry.

Keywords: additives, hardening, peat soil, plasticity index, soil stabilization

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1445 Government Policy over the Remuneration System of The Board of Commissioners in Indonesian Stated-Owned Enterprises

Authors: Synthia Atas Sari

Abstract:

The purpose of this paper is to examine the impact of reward system which determine by government over the work of Board of Commissioners to implement good corporate governance in Indonesian state-owned enterprises. To do so, this study analyzes the adequacy of the remuneration, the job attractiveness, and the board commitment and dedication with the remuneration system. Qualitative method used to examine the significant features and challenges to the government policy over the remuneration determination for the board of commissioners to their roles. Data gathered through semi-structure in-depth interview to the twenty-one participants over nine Indonesian stated-owned enterprises and written documents. Findings of this study indicate that government policies over the remuneration system is not effective to increase the performance of board of commissioners in implementing good corporate governance in Indonesian stated-owned enterprises due to unattractiveness of the remuneration amount, demotivate active members, and conflict interest over members of the remuneration committee.

Keywords: reward system, board of commissioners, stated-owned enterprises, government policy

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1444 Determination of Full Energy Peak Efficiency and Resolution of Nai (Tl) Detector Using Gamma-ray Spectroscopy

Authors: Jibon Sharma, Alakjyoti Patowary, Moirangthem Nara Singh

Abstract:

In experimental research it is very much essential to obtain the quality control of the system used for the experiment. NaI (Tl) scintillation detector is the most commonly used in radiation and medical physics for measurement of the gamma ray activity of various samples. In addition, the scintillation detector has a lot of applications in the elemental analysis of various compounds, alloys using activation analysis. In each application for quantitative analysis, it is very much essential to know the detection efficiency and resolution for different gamma energies. In this work, the energy dependence of efficiency and resolution of NaI (Tl) detector using gamma-ray spectroscopy are investigated. Different photon energies of 356.01 keV,511keV,661.60keV,1170 keV,1274.53 keV and 1330 keV are obtained from four radioactive sources (133Ba,22Na,137Cs and 60 Co) used in these studies. Values of full energy peak efficiencies of these gamma energies are found to be respectively 58.46%,10.15%,14.39%,1.4%,3.27% and 1.31%. The values of percent resolution for above different gamma ray energies are found to be 11.27%,7.27%,6.38%,5.17%,4.86% and 4.74% respectively. It was found that the efficiency of the detector exponentially decreases with energy and the resolution of the detector is directly proportional to the energy of gamma-ray.

Keywords: naI (Tl) gamma-ray spectrometer, resolution, full energy peak efficiency, radioactive sources

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1443 Numerical Simulation of Kangimi Reservoir Sedimentation, Kaduna State, Nigeria

Authors: Abdurrasheed Sa'id, Abubakar Isma'il, Waheed Alayande

Abstract:

This study focused on carrying out numerical simulations of Kangimi reservoir sedimentation by reviewing different numerical sediment transport models, and GSTARS3 was selected. The model was developed using the 1977 data. It was calibrated by simulating the 2012 profile and sediment deposition and compared with 2012 hydrographic survey results of NWRI. The model was validated by simulating the 2016 deposition and compared the results with NWRI estimates. Also, the performance of the proposed model was tested using statistical parameters such as MSE (Mean Square Error), MAPE (Mean Average Percentage Error) and R2 (Coefficient of determination) with values of 1.32m, 0.17% and 0.914 respectively which shows strong agreement. After the calibration, validation and performance testing the model was used to simulate the 2032 and 2062 profiles and deposition. The results showed that by 2032 the reservoir will be silted by 25.34MCM or 43.3% of the design capacity and 60.7% of the capacity by the year 2062. A number of sedimentation mitigation measures were recommended.

Keywords: NWRI- national water resources institute, sedimentation, GSTARS3, model

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1442 Stabilization of Spent Engine Oil Contaminated Lateritic Soil Admixed with Cement Kiln Dust for Use as Road Construction Materials

Authors: Johnson Rotimi Oluremi, A. Adedayo Adegbola, A. Samson Adediran, O. Solomon Oladapo

Abstract:

Spent engine oil contains heavy metals and polycyclic aromatic hydrocarbons which contribute to chronic health hazards, poor soil aeration, immobilisation of nutrients and lowering of pH in soil. It affects geotechnical properties of lateritic soil thereby constituting geotechnical and foundation problems. This study is therefore based on the stabilization of spent engine oil (SEO) contaminated lateritic soil using cement kiln dust (CKD) as a mean of restoring it to its pristine state. Geotechnical tests which include sieve analysis, atterberg limit, compaction, California bearing ratio and unconfined compressive strength tests were carried out on the natural, SEO contaminated and CKD stabilized SEO contaminated lateritic soil samples. The natural soil classified as A-2-7 (2) by AASHTO classification and GC according to the Unified Soil Classification System changed to A-4 non-plastic soil due to SEO contaminated even under the influence of CKD it remained unchanged. However, the maximum dry density (MDD) of the SEO contaminated soil increased while the optimum moisture content (OMC) behaved vice versa with the increase in the percentages of CKD. Similarly, the bearing strength of the stabilized SEO contaminated soil measured by California Bearing Ratio (CBR) increased with percentage increment in CKD. In conclusion, spent engine oil has a detrimental effect on the geotechnical properties of the lateritic soil sample but which can be remediated using 10% CKD as a stand alone admixture in stabilizing spent engine oil contaminated soil.

Keywords: spent engine oil, lateritic soil, cement kiln dust, stabilization, compaction, unconfined compressive strength

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1441 Calculation of Water Economy Balance for Water Management

Authors: Vakhtang Geladze, Nana Bolashvili, Tamazi Karalashvili, Nino Machavariani, Ana Karalashvili, George Geladze, Nana Kvirkvelia

Abstract:

Fresh water deficit is one of the most important global problems today. It must be taken into consideration that in the nearest future fresh water crisis will become even more acute owing to the global climate warming and fast desertification processes in the world. Georgia is rich in water resources, but there are disbalance between the eastern and western parts of the country. The goal of the study is to integrate the recent mechanisms compatible with European standards into Georgian water resources management system on the basis of GIS. Moreover, to draw up water economy balance for the purpose of proper determination of water consumption priorities that will be an exchange ratio of water resources and water consumption of the concrete territory. For study region was choose south-eastern part of country, Kvemo kartli Region. This is typical agrarian region, tends to the desertification. The water supply of the region was assessed on the basis of water economy balance, which was first time calculated for this region.

Keywords: desertification, GIS, sustainable management, water management

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1440 The Use of an Extract from the Polish Variety of White Mulberry Leaves in Flat Bread of Paratha Type

Authors: Monika Przeor

Abstract:

The pace of life of modern society promotes the occurrence of affluence diseases. Functional food, which design and consumption by the consumer may be useful in the prevention of occurrence of different diseases, is becoming the alternative of food products available in the market. Design and determination of properties of flat bread of paratha type with the addition of an extract from the leaves of white mulberry became the overriding objective in the presented study. The centuries-old use of mulberry leaves in alternative medicine gave hope to obtain positive effects of the undertaken activity. In the designed product, stability, and content of polyphenols as well as their antioxidant properties were tested. Moreover, in the paper an aqueous extract of mulberry leaves obtained on semi-technical scale was described. It is rich in polyphenols, which results in its antioxidant activity. The addition of the extract significantly increased health-promoting qualities of paratha. The 3% extract addition to the dough turned out to be the most desired by the consumer group.

Keywords: mulberry leaves extract, flat bread, paratha, antioxidant activity

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1439 Life Cycle Assessment of Almond Processing: Off-ground Harvesting Scenarios

Authors: Jessica Bain, Greg Thoma, Marty Matlock, Jeyam Subbiah, Ebenezer Kwofie

Abstract:

The environmental impact and particulate matter emissions (PM) associated with the production and packaging of 1 kg of almonds were evaluated using life cycle assessment (LCA). The assessment began at the point of ready to harvest with a system boundary was a cradle-to-gate assessment of almond packaging in California. The assessment included three scenarios of off-ground harvesting of almonds. The three general off-ground harvesting scenarios with variations include the harvested almonds solar dried on a paper tarp in the orchard, the harvested almonds solar dried on the floor in a separate lot, and the harvested almonds dried mechanically. The life cycle inventory (LCI) data for almond production were based on previously published literature and data provided by Almond Board of California (ABC). The ReCiPe 2016 method was used to calculate the midpoint impacts. Using consequential LCA model, the global warming potential (GWP) for the three harvesting scenarios are 2.90, 2.86, and 3.09 kg CO2 eq/ kg of packaged almond for scenarios 1, 2a, and 3a, respectively. The global warming potential for conventional harvesting method was 2.89 kg CO2 eq/ kg of packaged almond. The particulate matter emissions for each scenario per hectare for each off-ground harvesting scenario is 77.14, 9.56, 66.86, and 8.75 for conventional harvesting and scenarios 1, 2, and 3, respectively. The most significant contributions to the overall emissions were from almond production. The farm gate almond production had a global warming potential of 2.12 kg CO2 eq/ kg of packaged almond, approximately 73% of the overall emissions. Based on comparisons between the GWP and PM emissions, scenario 2a was the best tradeoff between GHG and PM production.

Keywords: life cycle assessment, low moisture foods, sustainability, LCA

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1438 The Proximate Composition and Phytochemical Screening of Momordica Balsamina (Balsam Apple) Fruit and Leaves

Authors: Viruska Jaichand, John Jason Mellem, Viresh Mohanlall

Abstract:

Malnutrition is a global issue that affects both children and adults, irrespective of their socio-economic status. It is, therefore, important to find various means to tackle malnutrition. This is especially important as undernutrition and overnutrition can be linked to a variety of non-communicable diseases (NCDs). This study aimed to gather more insight into the nutritional and phytochemical quality of Momordica balsamina leaves and fruit (fruit pericarp, fruit flesh and seeds). Results showed that Momordica balsamina had a nutritional composition that would be advantageous to the human diet. The nutritional quality is verified by the presence of a high protein percentage across all samples (19.72%-29.08%), with the leaves containing the highest protein content (29.08%±0.77). There was also a low-fat content present across all samples, which ranged from 1.03% to 2.40%. The ash content indicated the presence of total minerals to be adequate (2.93%-21.16%), where the pericarp had the highest ash quantity (21.16%±0.09). The moisture levels were low (7.11%-13.40%). Momordica balsamina seeds had the highest carbohydrate content (67.84%±0.30). Rich in the major phytoconstituents, Momordica balsamina extracts were found to contain alkaloids, saponins, cardiac glycosides, steroids and triterpenoids. Based on these findings, it can thus be said that the incorporation of Momordica balsamina into an individual’s diet could prevent diseases associated with malnutrition, as well as it could be used to supplement the human diet in managing certain NCDs. Even though there were a number of bioactive compounds detected, further studies which would correlate the phytochemical constituents detected in Momordica balsamina and its effectiveness in treating various diseases are recommended.

Keywords: momordica balsamina, nutrients, proximate composition, bioactive compounds, phytoconstituents

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1437 Determination of Mercury in Gold Ores by CVAAS Method

Authors: Ratna Siti Khodijah, Mirzam Abdurrachman

Abstract:

Gold is recovered from gold ores. Within the ores, there are not only gold but also several types of precious metals. Copper, silver, and platinum group elements (ruthenium, rhodium, palladium, rhenium, osmium, and iridium) are metals commonly found in the ores. These metals combine to form an ore because they have the same properties. It is due to their position in periodic-system-of-elements are near to gold. However, the presence of mercury in every gold ore has not been mentioned, even though it is located right next to gold in the periodic-system-of-elements and they are located in the same block, d-block. Thus, it is possible that mercury is contained in the ores. Moreover, the elements of the same group with mercury—zinc and cadmium—sometimes can be found in the ores. It is suspected that mercury can not be detected because the processing of gold ores usually using fire assay method. Before the ores melting, mercury would evaporate because it has the lowest boiling point of all precious metal in the ores. Therefore, it suggested doing research on the presence of mercury in gold ores by CVAAS method. The results of this study would obtain the amount of mercury in gold ores that should be purified. So it can be produced economically if possible.

Keywords: boiling point, d-block, fire assay, precious metal

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1436 Hydrogenation of CO2 to Methanol over Copper-Zinc Oxide-Based Catalyst

Authors: S. F. H. Tasfy, N. A. M. Zabidi, M. S. Shaharun

Abstract:

Carbon dioxide is highly thermochemical stable molecules where it is very difficult to activate the molecule and achieve higher catalytic conversion into alcohols or other hydrocarbon compounds. In this paper, series of the bimetallic Cu/ZnO-based catalyst supported by SBA-15 were systematically prepared via impregnation technique with different Cu: Zn ratio for hydrogenation of CO2 to methanol. The synthesized catalysts were characterized by transmission electron microscopy (TEM), temperature programmed desorption, reduction, oxidation and pulse chemisorption (TPDRO), and surface area determination was also performed. All catalysts were tested with respect to the hydrogenation of CO2 to methanol in microactivity fixed-bed reactor at 250oC, 2.25 MPa, and H2/CO2 ratio of 3. The results demonstrate that the catalytic structure, activity, and methanol selectivity was strongly affected by the ratio between Cu: Zn, Where higher catalytic activity of 14 % and methanol selectivity of 92 % was obtained over Cu/ZnO-SBA-15 catalyst with Cu:Zn ratio of 7:3 wt. %. Comparing with the single catalyst, the synergetic between Cu and Zn provides additional active sites to adsorb more H2 and CO2 and accelerate the CO2 conversion, resulting in higher methanol production under mild reaction conditions.

Keywords: hydrogenation of carbon dioxide, methanol synthesis, Cu/ZnO-based catalyst, mesoporous silica (SBA-15), metal ratio

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1435 Electrospun Alginate Nanofibers Containing Spirulina Extract Double-Layered with Polycaprolactone Nanofibers

Authors: Seon Yeong Byeon, Hwa Sung Shin

Abstract:

Nanofibrous sheets are of interest in the beauty industries due to the properties of moisturizing, adhesion to skin and delivery of nutrient materials. The benefit and function of the cosmetic products should not be considered without safety thus a non-toxic manufacturing process is ideal when fabricating the products. In this study, we have developed cosmetic patches consisting of alginate and Spirulina extract, a marine resource which has antibacterial and antioxidant effects, without addition of harmful cross-linkers. The patches obtained their structural stabilities by layer-upon-layer electrospinning of an alginate layer on a formerly spread polycaprolactone (PCL) layer instead of crosslinking method. The morphological characteristics, release of Spirulina extract, water absorption, skin adhesiveness and cytotoxicity of the double-layered patches were assessed. The image of scanning electron microscopy (SEM) showed that the addition of Spirulina extract has made the fiber diameter of alginate layers thinner. Impregnation of Spirulina extract increased their hydrophilicity, moisture absorption ability and skin adhesive ability. In addition, wetting the pre-dried patches resulted in releasing the Spirulina extract within 30 min. The patches were detected to have no cytotoxicity in the human keratinocyte cell-based MTT assay, but rather showed increased cell viability. All the results indicate the bioactive and hydro-adhesive double-layered patches have an excellent applicability to bioproducts for personal skin care in the trend of ‘A mask pack a day’.

Keywords: alginate, cosmetic patch, electrospun nanofiber, polycaprolactone, Spirulina extract

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1434 Determination of Micronutrients in the Fruit of Cydonia oblonga Miller

Authors: Madrakhimova Sakhiba, Matmurotov Bakhtishod, Boltaboyava Zilola, Matchanov Alimjan

Abstract:

Analyzing the chemical composition of locally consumed food products is one of the urgent problems in the health sector today. Taking this into account, it analyzed the microelement content of Cydonia oblonga Miller (COM) fruit growing in the Republic of Uzbekistan using the ISP MS inductively coupled mass spectrometry method. fruits brought to a constant mass in the analysis were mineralized in a mixture of nitric acid-HNO₃ and hydrogen peroxide-H₂O₂ in a ratio of 3:2. The mineralized extract was diluted to 50 milliliters with double-distilled water and analyzed. The results of the analysis showed that the fruit is rich in micronutrients necessary for the human body, especially potassium-K and phosphorus-P among macroelements, Strontium-Sr and barium-Ba from microelements are more than other microelements. It was observed that the amount of trace elements contained in COM fruit does not exceed the permissible standards. Therefore, it can be recommended to eat this fruit every day to prevent various diseases that occur in the human body.

Keywords: cydonia oblonga miller, macroelement, microelement, inductively coupled mass spectrometry, hydrolysis, mineralization

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1433 Bulk Electrical Resistivity of Geopolymer Mortars: The Effect of Binder Composition and Alkali Concentration

Authors: Mahdi Babaee, Arnaud Castel

Abstract:

One of the main hurdles for commercial adaptation of geopolymer concrete (GPC) as a low-embodied-carbon alternative for Portland cement concrete (PCC) is the durability aspects and its long-term performance in aggressive/corrosive environments. GPC is comparatively a new engineering material and in the absence of a track record of successful durability performance, proper experimental studies to investigate different durability-related characteristics of GPC seem inevitable. In this context, this paper aims to study the bulk electrical resistivity of geopolymer mortars fabricated of blends of low-calcium fly ash (FA) and ground granulated blast-furnace slag (GGBS). Bulk electrical resistivity is recognized as one of the most important parameters influencing the rate of corrosion of reinforcing bars during the propagation phase of corrosion. To investigate the effect of alkali concentration on the resistivity of the samples, 100x200 mm mortar cylinders were cast at different alkali concentration levels, whereas the modulus ratio (the molar ratio of SiO2/Na2O) was fixed for the mixes, and the bulk electrical resistivity was then measured. Also, the effect of the binder composition was assessed with respect to the ratio of FA to GGBS used. Results show a superior performance of samples with higher GGBS content. Lower concentration of the solution has increased the resistivity by reducing the amount of mobile alkali ions in the pore solution. Moreover, GGBS-based samples showed a much sharper increase in the electrical resistivity with decreasing the moisture content.

Keywords: bulk resistivity, corrosion, durability, geopolymer concrete

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1432 Preliminary Study of Antimicrobial Activity against Escherichia coli sp. and Probiotic Properties of Lactic Acid Bacteria Isolated from Thailand Fermented Foods

Authors: Phanwipa Pangsri, Yawariyah Weahayee

Abstract:

The lactic acid bacteria (LAB) were isolated from 10 samples of fermented foods (Sa-tor-dong and Bodo) in South locality of Thailand. The 23 isolates of lactic acid bacteria were selected, which were exhibited a clear zone and growth on MRS agar supplemented with CaCO3. All of lactic acid bacteria were tested on morphological and biochemical. The result showed that all isolates were Gram’s positive, non-spore forming but only 10 isolates displayed catalase negative. The 10 isolates including BD 1.1, BD 1.2, BD 2.1, BD2.2, BD 2.3, BD 3.1, BD 4.1, BD 5.2, ST4.1, and ST 5.2 were selected for inhibition activity determination. Only 2 strains (ST 4.1 and BD 2.3) showed inhibition zone on agar, when using Escherichia coli sp. as target strain. The ST 4.1 showed highest inhibition zone on agar, which was selected for probiotic property testing. The ST4.1 isolate could grow in MRS broth containing a high concentration of sodium chloride 6%, bile salts 7%, pH 4-10 and vary temperature at 15-45^oC.

Keywords: lactic acid bacteria, probiotic, antimicrobial, probiotic property testing

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1431 Radioactive Contamination by ¹³⁷Cs in Marine Sediments Taken up from Cuba's North and South Coast

Authors: Marisé García Batlle, Juan Manuel Navarrete Tejero

Abstract:

In aquatic ecosystems, the main indicators of pollution are contaminated sediments, which are the primary repository of radionuclides and chemicals elements in the marine environment. Radioactive Contamination Factor (RCF) has been proposed as a suitable unit to measure the magnitude of radioactive contamination at global scale, caused mainly by more than 2,000 nuclear explosions tests performed during the 1945-65 period. It is obtained as percentage of contaminant radioactivity (¹³⁷Cs) compared to natural radioactivity (⁴⁰K), both expressed in Bq/g of marine sediments conditioned in Marinelli containers and detected in both NaI(Tl) and HPGe detectors. So, in this paper samples of marine sediments were taken up along the occidental Cuban coasts and analyzed by gamma spectrometry for the determination of gamma-emitting radioisotopes with energies between 60 and 2000 keV. The results proved that the proposed method is simple and suitable to evaluated radioactive contamination. Also, the RCF values provide an appropriate indicator to predict which pollution levels in the future will be and if the rate will go down as disintegrates the ¹³⁷Cs present when only 2,4 half-lives have passed away.

Keywords: Cuba, gamma spectrometry, marine sediments, radioactive pollution

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1430 The Duty of Application and Connection Providers Regarding the Supply of Internet Protocol by Court Order in Brazil to Determine Authorship of Acts Practiced on the Internet

Authors: João Pedro Albino, Ana Cláudia Pires Ferreira de Lima

Abstract:

Humanity has undergone a transformation from the physical to the virtual world, generating an enormous amount of data on the world wide web, known as big data. Many facts that occur in the physical world or in the digital world are proven through records made on the internet, such as digital photographs, posts on social media, contract acceptances by digital platforms, email, banking, and messaging applications, among others. These data recorded on the internet have been used as evidence in judicial proceedings. The identification of internet users is essential for the security of legal relationships. This research was carried out on scientific articles and materials from courses and lectures, with an analysis of Brazilian legislation and some judicial decisions on the request of static data from logs and Internet Protocols (IPs) from application and connection providers. In this article, we will address the determination of authorship of data processing on the internet by obtaining the IP address and the appropriate judicial procedure for this purpose under Brazilian law.

Keywords: IP address, digital forensics, big data, data analytics, information and communication technology

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1429 The Influence of Disturbances Generated by Arc Furnaces on the Power Quality

Authors: Z. Olczykowski

Abstract:

The paper presents the impact of work on the electric arc furnace. Arc equipment is one of the largest receivers powered by the power system. Electric arc disturbances arising during melting process occurring in these furnaces are the cause of an abrupt change of the passive power of furnaces. Currents drawn by these devices undergo an abrupt change, which in turn cause voltage fluctuations and light flicker. The quantitative evaluation of the voltage fluctuations is now the basic criterion of assessment of an influence of unquiet receiver on the supplying net. The paper presents the method of determination of range of voltage fluctuations and light flicker at parallel operation of arc devices. The results of measurements of voltage fluctuations and light flicker indicators recorded in power supply networks of steelworks were presented, with different number of parallel arc devices. Measurements of energy quality parameters were aimed at verifying the proposed method in practice. It was also analyzed changes in other parameters of electricity: the content of higher harmonics, asymmetry, voltage dips.

Keywords: power quality, arc furnaces, propagation of voltage fluctuations, disturbances

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1428 Pull-In Instability Determination of Microcapacitive Sensor for Measuring Special Range of Pressure

Authors: Yashar Haghighatfar, Shahrzad Mirhosseini

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Pull-in instability is a nonlinear and crucial effect that is important for the design of microelectromechanical system devices. In this paper, the appropriate electrostatic voltage range is determined by measuring fluid flow pressure via micro pressure sensor based microbeam. The microbeam deflection contains two parts, the static and perturbation deflection of static. The second order equation regarding the equivalent stiffness, mass and damping matrices based on Galerkin method is introduced to predict pull-in instability due to the external voltage. Also the reduced order method is used for solving the second order nonlinear equation of motion. Furthermore, in the present study, the micro capacitive pressure sensor is designed for measuring special fluid flow pressure range. The results show that the measurable pressure range can be optimized, regarding damping field and external voltage.

Keywords: MEMS, pull-in instability, electrostatically actuated microbeam, reduced order method

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1427 Physical Characteristics of Locally Composts Produced in Saudi Arabia and the Need for Regulations

Authors: Ahmad Al-Turki

Abstract:

Composting is the suitable way of recycling organic waste for agricultural application and environment protection. In Saudi Arabia, several composting facilities are available and producing high quantity of composts. The aim of this study is to evaluate the physical characteristics of composts manufactured in Saudi Arabia and acquire a comprehensive image of its quality through the comparative with international standards of compost quality such as CCQC and PAS-100. In the present study different locally produced compost were identified and most of the producing factories were visited during the manufacturing of composts. Representative samples of different compost production stage were collected and Physical characteristics were determined, which included moisture content, bulk density, percentage of sand and the size of distribution of the compost particles. Results showed wide variations in all parameters investigated. Results of the study indicated generally that there is a wide variation in the physical characteristics of the types of compost under study. The initial moister contents in composts were generally low, it was less than 60% in most samples and not sufficient for microbial activities for biodegradation in 96% of the 96% of the types of compost and this will impede the decomposition of organic materials. The initial bulk density values ranged from 117 gL-1 to 1110.0 gL-1, while the final apparent bulk density ranged from 340.0 gL-1 to 1000gL-1 and about 45.4 % did not meet the ideal bulk density value. Sand percents in composts were between 3.3 % and 12.5%. This study has confirmed the need for a standard specification for compost manufactured in Saudi Arabia for agricultural use based on international standards for compost and soil characteristics and climatic conditions in Saudi Arabia.

Keywords: compost, maturity, Saudi Arabia, organic material

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1426 Combination of Electrochemical Impedance Spectroscopy and Electromembrane Extraction for the Determination of Zolpidem Using Modified Screen-Printed Electrode

Authors: Ali Naeemy, Mir Ghasem Hoseini

Abstract:

In this study, for the first time, an analytical method developed and validated by combining electrochemical impedance spectroscopy and electromembrane extraction (EIS-EME) by Vulcan/poly pyrrole nanocomposite modified screen-printed electrode (PPY–VU/SPE) for accurately quantifying zolpidem. EME parameters optimized, including solvent composition, voltage, pH adjustments and extraction time. Zolpidem was transferred from a donor solution (pH 5) to an acceptor solution (pH 13) using a hollow fiber in 1-octanol as a membrane, driven by a 60 V voltage for 25 minutes, ensuring precise and selective extraction. In comparison with SPE, VU/SPE and PPY/SPE, the PPY–VU/SPE was much more efficient for ZP oxidation. Calibration curves with good linearity were obtained in the concentration range of 2-75 µmol L-1 using the EIS-EME with the detection limit of 0.5 µmol L-1 . Finally, the EIS-EME by using the PPY– VU/SPE was successfully used to determine ZP in tablet dosage form, urine and plasma samples. Keywords: Electrochemical impedance spectroscopy, Electromembrane extraction, Zolpidem, Vulcan, poly pyrrole, Screen printed electrode

Keywords: electrochemical impedance spectroscopy, electromembrane extraction, screen printed electrode, zolpidem

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1425 Wind Farm Power Performance Verification Using Non-Parametric Statistical Inference

Authors: M. Celeska, K. Najdenkoski, V. Dimchev, V. Stoilkov

Abstract:

Accurate determination of wind turbine performance is necessary for economic operation of a wind farm. At present, the procedure to carry out the power performance verification of wind turbines is based on a standard of the International Electrotechnical Commission (IEC). In this paper, nonparametric statistical inference is applied to designing a simple, inexpensive method of verifying the power performance of a wind turbine. A statistical test is explained, examined, and the adequacy is tested over real data. The methods use the information that is collected by the SCADA system (Supervisory Control and Data Acquisition) from the sensors embedded in the wind turbines in order to carry out the power performance verification of a wind farm. The study has used data on the monthly output of wind farm in the Republic of Macedonia, and the time measuring interval was from January 1, 2016, to December 31, 2016. At the end, it is concluded whether the power performance of a wind turbine differed significantly from what would be expected. The results of the implementation of the proposed methods showed that the power performance of the specific wind farm under assessment was acceptable.

Keywords: canonical correlation analysis, power curve, power performance, wind energy

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1424 Design and Analysis of a Piezoelectric-Based AC Current Measuring Sensor

Authors: Easa Ali Abbasi, Akbar Allahverdizadeh, Reza Jahangiri, Behnam Dadashzadeh

Abstract:

Electrical current measurement is a suitable method for the performance determination of electrical devices. There are two contact and noncontact methods in this measuring process. Contact method has some disadvantages like having direct connection with wire which may endamage the system. Thus, in this paper, a bimorph piezoelectric cantilever beam which has a permanent magnet on its free end is used to measure electrical current in a noncontact way. In mathematical modeling, based on Galerkin method, the governing equation of the cantilever beam is solved, and the equation presenting the relation between applied force and beam’s output voltage is presented. Magnetic force resulting from current carrying wire is considered as the external excitation force of the system. The results are compared with other references in order to demonstrate the accuracy of the mathematical model. Finally, the effects of geometric parameters on the output voltage and natural frequency are presented.

Keywords: cantilever beam, electrical current measurement, forced excitation, piezoelectric

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1423 Selenium Content in Agricultural Soils and Wheat from the Balkan Peninsula

Authors: S. Krustev, V. Angelova, P. Zaprjanova

Abstract:

Selenium (Se) is an essential micro-nutrient for human and animals but it is highly toxic. Its organic compounds play an important role in biochemistry and nutrition of the cells. Concentration levels of this element in the different regions of the world vary considerably. This study aimed to compare the availability and levels of the Se in some rural areas of the Balkan Peninsula and relationship with the concentrations of other trace elements. For this purpose soil samples and wheat grains from different regions of Bulgaria, Serbia, Nord Macedonia, Romania, and Greece situated far from large industrial centers have been analyzed. The main methods for their determination were the atomic spectral techniques – atomic absorption and plasma atomic emission. As a result of this study, data on microelements levels from the main grain-producing regions of the Balkan Peninsula were determined and systematized. The presented results confirm the low levels of Se in this region: 0.222– 0.962 mg.kg-1 in soils and 0.001 - 0.005 mg.kg-1 in wheat grains and require measures to offset the effect of this deficiency.

Keywords: agricultural soils, balkan peninsula, rural areas, selenium

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1422 Determination of Optimum Water Consumptive Using Deficit Irrigation Model for Barely: A Case Study in Arak, Iran

Authors: Mohsen Najarchi

Abstract:

This research was carried out in five fields (5-15 hectares) in Arak located in center of Iran, to determine optimum level of water consumed for Barely in four stages growth (vegetative, yield formation, flowering, and ripening). Actual evapotranspiration was calculated using measured water requirement in the fields. Five levels of water requirement equal to 50, 60, 70, 80, and 90 percents formed the treatments. To determine the optimum level of water requirement linear programming was used. The study showed 60 percent water requirement (40 percent deficit irrigation) has been the optimum level of irrigation for winter wheat in four stages of growth. Comparison between all of the treatments indicated above with normal condition (100% water requirement) shows increasing in water use efficiency. Although 40% deficit irrigation treatment lead to decrease of 38% in yield, net benefit was increasing in 11.37%. Furthermore, in comparison with normal condition, 70% of water requirement increased water use efficiency as 30%.

Keywords: optimum, deficit irrigation, water use efficiency, evapotranspiration

Procedia PDF Downloads 379
1421 Pressure Losses on Realistic Geometry of Tracheobronchial Tree

Authors: Michaela Chovancova, Jakub Elcner

Abstract:

Real bronchial tree is very complicated piping system. Analysis of flow and pressure losses in this system is very difficult. Due to the complex geometry and the very small size in the lower generations is examination by CFD possible only in the central part of bronchial tree. For specify the pressure losses of lower generations is necessary to provide a mathematical equation. Determination of mathematical formulas for calculating the pressure losses in the real lungs is due to its complexity and diversity lengthy and inefficient process. For these calculations is necessary the lungs to slightly simplify (same cross-section over the length of individual generation) or use one of the models of lungs. The simplification could cause deviations from real values. The article compares the values of pressure losses obtained from CFD simulation of air flow in the central part of the real bronchial tree with the values calculated in a slightly simplified real lungs by using a mathematical relationship derived from the Bernoulli equation and continuity equation. Then, evaluate the desirability of using this formula to determine the pressure loss across the bronchial tree.

Keywords: pressure gradient, airways resistance, real geometry of bronchial tree, breathing

Procedia PDF Downloads 307
1420 Impact of Edible Coatings Made of Chitosan and Spray Dried Propolis in the Shell Life of White Cachama (Piaractus brachypomus)

Authors: David Guillermo Piedrahita Marquez, Hector Suarez Mahecha, Jairo Humberto Lopez

Abstract:

There is a need to preserve aquaculture matrices due to their high nutritional value, and its broad consumption, one of those species is the white cachama (Piaractus brachypomus), this fish is located in the rivers of eastern Colombia, and the previously mentioned species needs more study. Therefore, in a paper the effects of an alternative method of preservation of shell life were investigated, the method used is the application of an edible coating made from chitosan and ethanolic extract of propolis (EEP) encapsulated in maltodextrin. The coating was applied by immersion, and after that, we investigated the post mortem quality changes of the fish performing physicochemical and microbiological analysis. pH, volatile bases, test thiobarbituric acid and peroxide value were tested; finally, we studied the effect of the coating on mesophilic strains, coliforms and other microorganisms such as Staphylococcus, and Salmonella. Finally, we concluded that the coating prolongs the shelf life because it acts as a barrier to oxygen and moisture, the bioactive compounds trap free radicals and the coatings changes the metabolism and cause the cell lysis of the microorganisms. It was determined that the concentration of malonaldehyde, the volatile basic nitrogen content and pH are the variables that distinguish more clearly between the samples with the treatment and the control samples.

Keywords: antimicrobial activity, lipid oxidation, texture profile analysis (TPA), sensorial analysis, peroxide value, thiobarbituric acid assay (TBA), total volatile basic nitrogen (TVB-N)

Procedia PDF Downloads 276
1419 The Role of Organizational Culture, Organizational Commitment, and Styles of Transformational Leadership towards Employee Performance

Authors: Ahmad Badawi Saluy, Novawiguna Kemalasari

Abstract:

This study aims to examine and analyze the influence of organizational culture, organizational commitment, and transformational leadership style on employee performance. This study used descriptive survey method with quantitative approach, and questionnaires as a tool used for basic data collection. The sampling technique used is proportionate stratified random sampling technique; all respondents in this study were 70 respondents. The analytical method used in this research is multiple linear regressions. The result of determination coefficient of 52.3% indicates that organizational culture, organizational commitment, and transformational leadership style simultaneously have a significant influence on the performance of employees, while the remaining 47.7% is explained by other factors outside the research variables. Partially, organization culture has strong and positive influence on employee performance, organizational commitment has a moderate and positive effect on employee performance, while the transformational leadership style has a strong and positive influence on employee performance and this is also the variable that has the most impact on employee performance.

Keywords: organizational culture, organizational commitment, transformational leadership style, employee performance

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1418 Contemporary Global Urban Scenarios: An Essay on Urban Insurgencies

Authors: Clovis Ultramari, Lidia Floriani, Debora Cicioli

Abstract:

This paper is a preliminary discussion on the constituency of contemporary global urban scenarios. It is based on secondary sources, mostly from the topics mostly currently discussed by global studies institutes, academic material on the possible components of this phenomenon, and a list of possible scenarios preliminarily proposed by these authors. It also discusses one of these possible scenarios (urban insurgencies) through the lens of a global perspective. Main objective of the research presented in this paper is to produce insights for international aid and development agencies as well as to respond to an increasing interest in the urban studies field in discussing global topics. This paper also results from discussions held in seminars offered by the authors in the graduate program of Urban Management along 2021 and 2022. It is part of a research project that puts together an international team of researches, mostly from the Global South. Results so far obtained refer to conceptual aspects for the determination of global urban scenarios and the presentation of urban insurgencies as worldwide trending urban phenomenon. Presentation in the seminar is part of an ongoing discussion.

Keywords: urban global scenarios, contemporary cities, global south, urban insurgencies

Procedia PDF Downloads 90