Search results for: phase identification
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7146

Search results for: phase identification

5586 A Constrained Model Predictive Control Scheme for Simultaneous Control of Temperature and Hygrometry in Greenhouses

Authors: Ayoub Moufid, Najib Bennis, Soumia El Hani

Abstract:

The objective of greenhouse climate control is to improve the culture development and to minimize the production costs. A greenhouse is an open system to external environment and the challenge is to regulate the internal climate despite the strong meteorological disturbances. The internal state of greenhouse considered in this work is defined by too relevant and coupled variables, namely inside temperature and hygrometry. These two variables are chosen to describe the internal state of greenhouses due to their importance in the development of plants and their sensitivity to external climatic conditions, sources of weather disturbances. A multivariable model is proposed and validated by considering a greenhouse as black-box system and the least square method is applied to parameters identification basing on collected experimental measures. To regulate the internal climate, we propose a Model Predictive Control (MPC) scheme. This one considers the measured meteorological disturbances and the physical and operational constraints on the control and state variables. A successful feasibility study of the proposed controller is presented, and simulation results show good performances despite the high interaction between internal and external variables and the strong external meteorological disturbances. The inside temperature and hygrometry are tracking nearly the desired trajectories. A comparison study with an On/Off control applied to the same greenhouse confirms the efficiency of the MPC approach to inside climate control.

Keywords: climate control, constraints, identification, greenhouse, model predictive control, optimization

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5585 The Effect of the Structural Arrangement of Binary Bisamide Organogelators on their Self-Assembly Behavior

Authors: Elmira Ghanbari, Jan Van Esch, Stephen J. Picken, Sahil Aggarwal

Abstract:

Low-molecular-weight organogelators form gels by self-assembly into the crystalline network which immobilizes the organic solvent. For single bisamide organogelator systems, the effect of the molecular structure on the molecular interaction and their self-assembly behavior has been explored. The spatial arrangement of bisamide molecules in the gel-state is driven by a combination of hydrogen bonding and Van der Waals interactions. The hydrogen-bonding pattern between the amide groups of bisamide molecules is regulated by the number of methylene spacers; the even number of methylene spacers between two amide groups, in even-spaced bisamides, leads to the antiparallel position of amide groups within a molecule. An even-spaced bisamide molecule with antiparallel amide groups can make two pairs of hydrogen bonding with the molecules on the same plane. The odd-spaced bisamide with a parallel directionality of amide groups can form four independent hydrogen bonds with four other bisamide molecules on different planes. The arrangement of bisamide molecules in the crystalline state and the interaction of these molecules depends on the molecular structure, particularly the parity of the spacer length between the amide groups in the bisamide molecule. In this study, the directionality of amide groups has been exploited as a structural characteristic to affect the arrangement of molecules in the crystalline state and produce different binary bisamide gelators with different degrees of crystallinities. Single odd- and even-spaced single bisamides were synthesized and blended to produce binary bisamide organogelators to be characterized in order to understand the effect of the different directionality of amide groups on the molecular interaction in the crystalline state. The pattern of molecular interactions between these blended molecules, mixing or phase separation, has been monitored via differential scanning calorimetry (DSC) and crystallography techniques; X-ray powder diffraction (XRD) and Small-angle X-ray scattering (SAXS). The formation of lamellar structures for odd- and even-spaced bisamide gelators was confirmed by using SAXS and XRD techniques. DSC results have shown that binary bisamide organogelators with different parity of methylene spacers (odd-even binary blends) have a higher tendency for phase separation compared to the binary bisamides with the same parity (odd-odd or even-even binary blends). Phase separation in binary odd-even bisamides was confirmed by the presence of individual (100) reflections of odd and even lamellar structures. The structural characteristic of bisamide organogelators, the parity of spacer length in binary systems, is a promising tool to control the arrangement of molecules and their crystalline structure.

Keywords: binary bisamide organogelators, crystalline structure, phase separation, self-assembly behavior

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5584 Partial Discharge Characteristics of Free- Moving Particles in HVDC-GIS

Authors: Philipp Wenger, Michael Beltle, Stefan Tenbohlen, Uwe Riechert

Abstract:

The integration of renewable energy introduces new challenges to the transmission grid, as the power generation is located far from load centers. The associated necessary long-range power transmission increases the demand for high voltage direct current (HVDC) transmission lines and DC distribution grids. HVDC gas-insulated switchgears (GIS) are considered being a key technology, due to the combination of the DC technology and the long operation experiences of AC-GIS. To ensure long-term reliability of such systems, insulation defects must be detected in an early stage. Operational experience with AC systems has proven evidence, that most failures, which can be attributed to breakdowns of the insulation system, can be detected and identified via partial discharge (PD) measurements beforehand. In AC systems the identification of defects relies on the phase resolved partial discharge pattern (PRPD). Since there is no phase information within DC systems this method cannot be transferred to DC PD diagnostic. Furthermore, the behaviour of e.g. free-moving particles differs significantly at DC: Under the influence of a constant direct electric field, charge carriers can accumulate on particles’ surfaces. As a result, a particle can lift-off, oscillate between the inner conductor and the enclosure or rapidly bounces at just one electrode, which is known as firefly motion. Depending on the motion and the relative position of the particle to the electrodes, broadband electromagnetic PD pulses are emitted, which can be recorded by ultra-high frequency (UHF) measuring methods. PDs are often accompanied by light emissions at the particle’s tip which enables optical detection. This contribution investigates PD characteristics of free moving metallic particles in a commercially available 300 kV SF6-insulated HVDC-GIS. The influences of various defect parameters on the particle motion and the PD characteristic are evaluated experimentally. Several particle geometries, such as cylinder, lamella, spiral and sphere with different length, diameter and weight are determined. The applied DC voltage is increased stepwise from inception voltage up to UDC = ± 400 kV. Different physical detection methods are used simultaneously in a time-synchronized setup. Firstly, the electromagnetic waves emitted by the particle are recorded by an UHF measuring system. Secondly, a photomultiplier tube (PMT) detects light emission with a wavelength in the range of λ = 185…870 nm. Thirdly, a high-speed camera (HSC) tracks the particle’s motion trajectory with high accuracy. Furthermore, an electrically insulated electrode is attached to the grounded enclosure and connected to a current shunt in order to detect low frequency ion currents: The shunt measuring system’s sensitivity is in the range of 10 nA at a measuring bandwidth of bw = DC…1 MHz. Currents of charge carriers, which are generated at the particle’s tip migrate through the gas gap to the electrode and can be recorded by the current shunt. All recorded PD signals are analyzed in order to identify characteristic properties of different particles. This includes e.g. repetition rates and amplitudes of successive pulses, characteristic frequency ranges and detected signal energy of single PD pulses. Concluding, an advanced understanding of underlying physical phenomena particle motion in direct electric field can be derived.

Keywords: current shunt, free moving particles, high-speed imaging, HVDC-GIS, UHF

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5583 Organic Geochemical Characteristics of Cenozoic Mudstones, NE Bengal Basin, Bangladesh

Authors: H. M. Zakir Hossain

Abstract:

Cenozoic mudstone samples, obtained from drilled cored and outcrop in northeastern Bengal Basin of Bangladesh were organic geochemically analyzed to identify vertical variations of organic facies, thermal maturity, hydrocarbon potential and depositional environments. Total organic carbon (TOC) content ranges from 0.11 to 1.56 wt% with an average of 0.43 wt%, indicating a good source rock potential. Total sulphur content is variable with values ranging from ~0.001 to 1.75 wt% with an average of 0.065 wt%. Rock-Eval S1 and S2 yields range from 0.03 to 0.14 mg HC/g rock and 0.01 to 0.66 mg HC/g rock, respectively. The hydrogen index values range from 2.71 to 56.09 mg HC/g TOC. These results revealed that the samples are dominated by type III kerogene. Tmax values of 426 to 453 °C and vitrinite reflectance of 0.51 to 0.66% indicate the organic matter is immature to mature. Saturated hydrocarbon ratios such as pristane, phytane, steranes, and hopanes, indicate mostly terrigenous organic matter with small influence of marine organic matter. Organic matter in the succession was accumulated in three different environmental conditions based on the integration of biomarker proxies. First phase (late Eocene to early Miocene): Deposition occurred entirely in seawater-dominated oxic conditions, with high inputs of land plants organic matter including angiosperms. Second phase (middle to late Miocene): Deposition occurred in freshwater-dominated anoxic conditions, with phytoplanktonic organic matter and a small influence of land plants. Third phase (late Miocene to Pleistocene): Deposition occurred in oxygen-poor freshwater conditions, with abundant input of planktonic organic matter and high influx of angiosperms. The lower part (middle Eocene to early Miocene) of the succession with moderate TOC contents and primarily terrestrial organic matter could have generated some condensates and oils in and around the study area.

Keywords: Bangladesh, geochemistry, hydrocarbon potential, mudstone

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5582 Cheiloscopy: A Study on Predominant Lip Print Patterns among the Gujarati Population

Authors: Pooja Ahuja, Tejal Bhutani, M. S. Dahiya

Abstract:

Cheiloscopy, the study of lip prints, is a tool in forensic investigation technique that deals with identification of individuals based on lips patterns. The objective of this study is to determine predominant lip print pattern found among the Gujarati population, to evaluate whether any sex difference exists and to study the permanence of the pattern over six months duration. The study comprised of 100 healthy individuals (50 males and 50 females), in the age group of 18 to 25 years of Gujarati population of the Gandhinagar region of the Gujarat state, India. By using Suzuki and Tsuchihashi classification, Lip prints were then divided into four quadrants and also classified on the basis of peripheral shape of the lips. Materials used to record the lip prints were dark brown colored lipstick, cellophane tape, and white bond paper. Lipstick was applied uniformly, and lip prints were taken on the glued portion of cellophane tape and then stuck on to a white bond paper. These lip prints were analyzed with magnifying lens and virtually with stereo microscope. On the analysis of the subject population, results showed Branched pattern Type II (29.57 percentage) to be most predominant in the Gujarati population. Branched pattern Type II (35.60 percentage) and long vertical Type I (28.28 percentage) were most prevalent in males and females respectively and large full lips were most predominantly present in both the sexes. The study concludes that lip prints in any form can be an effective tool for identification of an individual in a closed or open group forms.

Keywords: cheiloscopy, lip pattern, predomianant, Gujarati population

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5581 Cheiloscopy and Dactylography in Relation to ABO Blood Groups: Egyptian vs. Malay Populations

Authors: Manal Hassan Abdel Aziz, Fatma Mohamed Magdy Badr El Dine, Nourhan Mohamed Mohamed Saeed

Abstract:

Establishing association between lip print patterns and those of fingerprints as well as blood groups is of fundamental importance in the forensic identification domain. The first aim of the current study was to determine the prevalent types of ABO blood groups, lip prints and fingerprints patterns in both studied populations. Secondly, to analyze any relation found between the different print patterns and the blood groups, which would be valuable in identification purposes. The present study was conducted on 60 healthy volunteers, (30 males and 30 females) from each of the studied population. Lip prints and fingerprints were obtained and classified according to Tsuchihashi's classification and Michael Kuchen’s classification, respectively. The results show that the ulnar loop was the most frequent among both populations. Blood group A was the most frequent among Egyptians, while blood groups O and B were the predominant among Malaysians. Significant relations were observed between lip print patterns and fingerprint (in the second quadrant for Egyptian males and the first one for Malaysian). For Malaysian females, a statistically significant association was proved in the fourth quadrant. Regarding the blood groups, 89.5% of ulnar loops were significantly related to blood group A among Egyptian males. The results proved an association between the fingerprint pattern and the lip prints, as well as between the ABO blood group and the pattern of fingerprints. However, further researches with larger sample sizes need to be directed to approve the current results.

Keywords: ABO, cheiloscopy, dactylography, Egyptians, Malaysians

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5580 A Grid Synchronization Method Based On Adaptive Notch Filter for SPV System with Modified MPPT

Authors: Priyanka Chaudhary, M. Rizwan

Abstract:

This paper presents a grid synchronization technique based on adaptive notch filter for SPV (Solar Photovoltaic) system along with MPPT (Maximum Power Point Tracking) techniques. An efficient grid synchronization technique offers proficient detection of various components of grid signal like phase and frequency. It also acts as a barrier for harmonics and other disturbances in grid signal. A reference phase signal synchronized with the grid voltage is provided by the grid synchronization technique to standardize the system with grid codes and power quality standards. Hence, grid synchronization unit plays important role for grid connected SPV systems. As the output of the PV array is fluctuating in nature with the meteorological parameters like irradiance, temperature, wind etc. In order to maintain a constant DC voltage at VSC (Voltage Source Converter) input, MPPT control is required to track the maximum power point from PV array. In this work, a variable step size P & O (Perturb and Observe) MPPT technique with DC/DC boost converter has been used at first stage of the system. This algorithm divides the dPpv/dVpv curve of PV panel into three separate zones i.e. zone 0, zone 1 and zone 2. A fine value of tracking step size is used in zone 0 while zone 1 and zone 2 requires a large value of step size in order to obtain a high tracking speed. Further, adaptive notch filter based control technique is proposed for VSC in PV generation system. Adaptive notch filter (ANF) approach is used to synchronize the interfaced PV system with grid to maintain the amplitude, phase and frequency parameters as well as power quality improvement. This technique offers the compensation of harmonics current and reactive power with both linear and nonlinear loads. To maintain constant DC link voltage a PI controller is also implemented and presented in this paper. The complete system has been designed, developed and simulated using SimPower System and Simulink toolbox of MATLAB. The performance analysis of three phase grid connected solar photovoltaic system has been carried out on the basis of various parameters like PV output power, PV voltage, PV current, DC link voltage, PCC (Point of Common Coupling) voltage, grid voltage, grid current, voltage source converter current, power supplied by the voltage source converter etc. The results obtained from the proposed system are found satisfactory.

Keywords: solar photovoltaic systems, MPPT, voltage source converter, grid synchronization technique

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5579 Shear Behavior of Reinforced Concrete Beams Casted with Recycled Coarse Aggregate

Authors: Salah A. Aly, Mohammed A. Ibrahim, Mostafa M. khttab

Abstract:

The amount of construction and demolition (C&D) waste has increased considerably over the last few decades. From the viewpoint of environmental preservation and effective utilization of resources, crushing C&D concrete waste to produce coarse aggregate (CA) with different replacement percentage for the production of new concrete is one common means for achieving a more environment-friendly concrete. In the study presented herein, the investigation was conducted in two phases. In the first phase, the selection of the materials was carried out and the physical, mechanical and chemical characteristics of these materials were evaluated. Different concrete mixes were designed. The investigation parameter was Recycled Concrete Aggregate (RCA) ratios. The mechanical properties of all mixes were evaluated based on compressive strength and workability results. Accordingly, two mixes have been chosen to be used in the next phase. In the second phase, the study of the structural behavior of the concrete beams was developed. Sixteen beams were casted to investigate the effect of RCA ratios, the shear span to depth ratios and the effect of different locations and reinforcement of openings on the shear behavior of the tested specimens. All these beams were designed to fail in shear. Test results of the compressive strength of concrete indicated that, replacement of natural aggregate by up to 50% recycled concrete aggregates in mixtures with 350 Kg/m3 cement content led to increase of concrete compressive strength. Moreover, the tensile strength and the modulus of elasticity of the specimens with RCA have very close values to those with natural aggregates. The ultimate shear strength of beams with RCA is very close to those with natural aggregates indicating the possibility of using RCA as partial replacement to produce structural concrete elements. The validity of both the Egyptian Code for the design and implementation of Concrete Structures (ECCS) 203-2007 and American Concrete Institute (ACI) 318-2011Codes for estimating the shear strength of the tested RCA beams was investigated. It was found that the codes procedures gives conservative estimates for shear strength.

Keywords: construction and demolition (C&D) waste, coarse aggregate (CA), recycled coarse aggregates (RCA), opening

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5578 Data Protection and Regulation Compliance on Handling Physical Child Abuse Scenarios- A Scoping Review

Authors: Ana Mafalda Silva, Rebeca Fontes, Ana Paula Vaz, Carla Carreira, Ana Corte-Real

Abstract:

Decades of research on the topic of interpersonal violence against minors highlight five main conclusions: 1) it causes harmful effects on children's development and health; 2) it is prevalent; 3) it violates children's rights; 4) it can be prevented and 5) parents are the main aggressors. The child abuse scenario is identified through clinical observation, administrative data and self-reports. The most used instruments are self-reports; however, there are no valid and reliable self-report instruments for minors, which consist of a retrospective interpretation of the situation by the victim already in her adult phase and/or by her parents. Clinical observation and collection of information, namely from the orofacial region, are essential in the early identification of these situations. The management of medical data, such as personal data, must comply with the General Data Protection Regulation (GDPR), in Europe, and with the General Law of Data Protection (LGPD), in Brazil. This review aims to answer the question: In a situation of medical assistance to minors, in the suspicion of interpersonal violence, due to mistreatment, is it necessary for the guardians to provide consent in the registration and sharing of personal data, namely medical ones. A scoping review was carried out based on a search by the Web of Science and Pubmed search engines. Four papers and two documents from the grey literature were selected. As found, the process of identifying and signaling child abuse by the health professional, and the necessary early intervention in defense of the minor as a victim of abuse, comply with the guidelines expressed in the GDPR and LGPD. This way, the notification in maltreatment scenarios by health professionals should be a priority and there shouldn’t be the fear or anxiety of legal repercussions that stands in the way of collecting and treating the data necessary for the signaling procedure that safeguards and promotes the welfare of children living with abuse.

Keywords: child abuse, disease notifications, ethics, healthcare assistance

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5577 Robust Fractional Order Controllers for Minimum and Non-Minimum Phase Systems – Studies on Design and Development

Authors: Anand Kishore Kola, G. Uday Bhaskar Babu, Kotturi Ajay Kumar

Abstract:

The modern dynamic systems used in industries are complex in nature and hence the fractional order controllers have been contemplated as a fresh approach to control system design that takes the complexity into account. Traditional integer order controllers use integer derivatives and integrals to control systems, whereas fractional order controllers use fractional derivatives and integrals to regulate memory and non-local behavior. This study provides a method based on the maximumsensitivity (Ms) methodology to discover all resilient fractional filter Internal Model Control - proportional integral derivative (IMC-PID) controllers that stabilize the closed-loop system and deliver the highest performance for a time delay system with a Smith predictor configuration. Additionally, it helps to enhance the range of PID controllers that are used to stabilize the system. This study also evaluates the effectiveness of the suggested controller approach for minimum phase system in comparison to those currently in use which are based on Integral of Absolute Error (IAE) and Total Variation (TV).

Keywords: modern dynamic systems, fractional order controllers, maximum-sensitivity, IMC-PID controllers, Smith predictor, IAE and TV

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5576 Structural, Magnetic, Electrical and Dielectric Properties of Pr0.8Na0.2MnO3 Manganite

Authors: H. Ben Khlifa, W. Cheikhrouhou, R. M'nassri

Abstract:

The Orthorhombic Pr0.8Na0.2MnO3 ceramic was prepared in Polycrystalline form by a Pechini sol–gel method and its structural, magnetic, electrical, and dielectric properties were investigated experimentally. A structural study confirms that the sample is a single phase. Magnetic measurements show that the sample is a charge ordered Manganite. The sample undergoes two successive magnetic phase transitions with the variation of temperature: a charge ordering transition occurred at TCO = 212 K followed by a Paramagnetic (PM) to ferromagnetic (FM) transition around TC = 115 K. From an electrical point of view, a saturation region was marked in the conductivity as a function of Temperature s(T) curves at a specific temperature. The dc-conductivity (sdc) reaches a maximum value at 240 K. The obtained results are in good agreement with the temperature dependence of the average normalized change (ANC). We found that the conduction mechanism was governed by small polaron hopping (SPH) in the high-temperature region and by variable range hopping (VRH) in the low-temperature region. Complex impedance analysis indicates the presence of a non-Debye relaxation phenomenon in the system. Also, the compound was modeled by an electrical equivalent circuit. Then, the contribution of the grain boundary in the transport properties was confirmed.

Keywords: manganites, preparation methods, magnetization, magnetocaloric effect, electrical and dielectric

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5575 Sulfide Removal from Liquid Using Biofilm on Packed Bed of Salak Fruit Seeds

Authors: Retno Ambarwati Sigit Lestari, Wahyudi Budi Sediawan, Sarto Sarto

Abstract:

This study focused on the removal of sulfide from liquid solution using biofilm on packed bed of salak fruit seeds. Biofilter operation of 444 hours consists of 6 phases of operation. Each phase lasted for approximately 72 hours to 82 hours and run at various inlet concentration and flow rate. The highest removal efficiency is 92.01%, at the end of phase 7 at the inlet concentration of 60 ppm and the flow rate of 30 mL min-1. Mathematic model of sulfide removal was proposed to describe the operation of biofilter. The model proposed can be applied to describe the removal of sulfide liquid using biofilter in packed bed. The simulation results the value of the parameters in process. The value of the rate maximum spesific growth is 4.15E-8 s-1, Saturation constant is 9.1E-8 g cm-3, mass transfer coefisient of liquid is 0.5 cm s-1, Henry’s constant is 0.007, and mass of microorganisms growth to mass of sulfide comsumed is 30. The value of the rate maximum spesific growth in early process is 0.00000004 s-1.

Keywords: biofilm, packed bed, removal, sulfide, salak fruit seeds.

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5574 Preparation and Characterization of CuFe2O4/TiO2 Photocatalyst for the Conversion of CO2 into Methanol under Visible Light

Authors: Md. Maksudur Rahman Khan, M. Rahim Uddin, Hamidah Abdullah, Kaykobad Md. Rezaul Karim, Abu Yousuf, Chin Kui Cheng, Huei Ruey Ong

Abstract:

A systematic study was conducted to explore the photocatalytic reduction of carbon dioxide (CO2) into methanol on TiO2 loaded copper ferrite (CuFe2O4) photocatalyst under visible light irradiation. The phases and crystallite size of the photocatalysts were characterized by X-ray diffraction (XRD) and it indicates CuFe2O4 as tetragonal phase incorporation with anatase TiO2 in CuFe2O4/TiO2 hetero-structure. The XRD results confirmed the formation of spinel type tetragonal CuFe2O4 phases along with predominantly anatase phase of TiO2 in the CuFe2O4/TiO2 hetero-structure. UV-Vis absorption spectrum suggested the formation of the hetero-junction with relatively lower band gap than that of TiO2. Photoluminescence (PL) technique was used to study the electron–hole (e/h+) recombination process. PL spectra analysis confirmed the slow-down of the recombination of electron–hole (e/h+) pairs in the CuFe2O4/TiO2 hetero-structure. The photocatalytic performance of CuFe2O4/TiO2 was evaluated based on the methanol yield with varying amount of TiO2 over CuFe2O4 (0.5:1, 1:1, and 2:1) and changing light intensity. The mechanism of the photocatalysis was proposed based on the fact that the predominant species of CO2 in aqueous phase were dissolved CO2 and HCO3- at pH ~5.9. It was evident that the CuFe2O4 could harvest the electrons under visible light irradiation, which could further be injected to the conduction band of TiO2 to increase the life time of the electron and facilitating the reactions of CO2 to methanol. The developed catalyst showed good recycle ability up to four cycles where the loss of activity was ~25%. Methanol was observed as the main product over CuFe2O4, but loading with TiO2 remarkably increased the methanol yield. Methanol yield over CuFe2O4/TiO2 was found to be about three times higher (651 μmol/gcat L) than that of CuFe2O4 photocatalyst. This occurs because the energy of the band excited electrons lies above the redox potentials of the reaction products CO2/CH3OH.

Keywords: photocatalysis, CuFe2O4/TiO2, band-gap energy, methanol

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5573 Design and Implementation of Image Super-Resolution for Myocardial Image

Authors: M. V. Chidananda Murthy, M. Z. Kurian, H. S. Guruprasad

Abstract:

Super-resolution is the technique of intelligently upscaling images, avoiding artifacts or blurring, and deals with the recovery of a high-resolution image from one or more low-resolution images. Single-image super-resolution is a process of obtaining a high-resolution image from a set of low-resolution observations by signal processing. While super-resolution has been demonstrated to improve image quality in scaled down images in the image domain, its effects on the Fourier-based technique remains unknown. Super-resolution substantially improved the spatial resolution of the patient LGE images by sharpening the edges of the heart and the scar. This paper aims at investigating the effects of single image super-resolution on Fourier-based and image based methods of scale-up. In this paper, first, generate a training phase of the low-resolution image and high-resolution image to obtain dictionary. In the test phase, first, generate a patch and then difference of high-resolution image and interpolation image from the low-resolution image. Next simulation of the image is obtained by applying convolution method to the dictionary creation image and patch extracted the image. Finally, super-resolution image is obtained by combining the fused image and difference of high-resolution and interpolated image. Super-resolution reduces image errors and improves the image quality.

Keywords: image dictionary creation, image super-resolution, LGE images, patch extraction

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5572 Comparison Of Virtual Non-Contrast To True Non-Contrast Images Using Dual Layer Spectral Computed Tomography

Authors: O’Day Luke

Abstract:

Purpose: To validate virtual non-contrast reconstructions generated from dual-layer spectral computed tomography (DL-CT) data as an alternative for the acquisition of a dedicated true non-contrast dataset during multiphase contrast studies. Material and methods: Thirty-three patients underwent a routine multiphase clinical CT examination, using Dual-Layer Spectral CT, from March to August 2021. True non-contrast (TNC) and virtual non-contrast (VNC) datasets, generated from both portal venous and arterial phase imaging were evaluated. For every patient in both true and virtual non-contrast datasets, a region-of-interest (ROI) was defined in aorta, liver, fluid (i.e. gallbladder, urinary bladder), kidney, muscle, fat and spongious bone, resulting in 693 ROIs. Differences in attenuation for VNC and TNV images were compared, both separately and combined. Consistency between VNC reconstructions obtained from the arterial and portal venous phase was evaluated. Results: Comparison of CT density (HU) on the VNC and TNC images showed a high correlation. The mean difference between TNC and VNC images (excluding bone results) was 5.5 ± 9.1 HU and > 90% of all comparisons showed a difference of less than 15 HU. For all tissues but spongious bone, the mean absolute difference between TNC and VNC images was below 10 HU. VNC images derived from the arterial and the portal venous phase showed a good correlation in most tissue types. The aortic attenuation was somewhat dependent however on which dataset was used for reconstruction. Bone evaluation with VNC datasets continues to be a problem, as spectral CT algorithms are currently poor in differentiating bone and iodine. Conclusion: Given the increasing availability of DL-CT and proven accuracy of virtual non-contrast processing, VNC is a promising tool for generating additional data during routine contrast-enhanced studies. This study shows the utility of virtual non-contrast scans as an alternative for true non-contrast studies during multiphase CT, with potential for dose reduction, without loss of diagnostic information.

Keywords: dual-layer spectral computed tomography, virtual non-contrast, true non-contrast, clinical comparison

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5571 Effect of Feeding Camel Rumen Content on Growth Performance and Haematological Parameters of Broiler Chickens under Semi-Arid Condition

Authors: Alhaji Musa Abdullahi, Usman Abdullahi, Adamu Adamu, Aminu Maidala

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One hundred and fifty (150) day old chicks were randomly allocated into five dietary treatments birds and each treatment where replicated twice in groups of fifteen birds in each replicate. Camel rumen content (CRC) was included in the diets of broiler at 0, 5, 10, 15, and 20% to replace maize and groundnut cake to evaluate the effect on the performance and hematological parameters at the starter and finisher phase. A completely randomized design was used and 600g of feed was given daily and water was given ad libitum. At the starter phase, the daily weight gain and feed conversion ratio were significantly affected by the test ingredients, although T1(0% CRC) which serve as a control, were similar with T2(5% CRC), T3(10% CRC), and T4(15% CRC), while the lowest value was recorded in T5(20% CRC). The result indicates that up to 15% (CRC) level can be included in the starter diet to replace maize and groundnut cake without any effect on the performance. However, at the finisher phase, the daily feed intake, daily weight gain and feed conversion ratio show no significant (F>0.05) difference among the dietary treatments. Similarly, Packed cell volume (PCV), Red Blood Cell (RBC), White Blood Cell (WBC), Mean Corpuscular Volume (MCV), and Mean Corpuscular Haemoglobin (MCH) also did not differ significantly (F>0.05) among the dietary treatments while hemoglobin (Hb) and Mean Corpuscular Haemoglobin Concentration (MCHC) differs significantly. The differential counts of eosinophils, heterophils, and lymphocytes differ significantly among the treatment groups, while that of basophils and monocytes shows no significant difference among the treatment groups. This means up to 20% CRC inclusion level can be used to replaced maize and groundnut cake in the finisher diet without any adverse effect on the performance and hematological parameters of the chickens.

Keywords: camel, rumen content, growth, hematology

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5570 Diffusion Treatment of Niobium and Molybdenum on Pur Titanium and Titanium Alloy Ti-64al and Their Properties

Authors: Kaouka Alaeddine, K. Benarous

Abstract:

This study aims to obtain a surface of pure titanium and titanium alloy Ti-64Al with high performance by the diffusion process. Two agents metal alloy have been used in this treatment, niobium (Nb) and molybdenum (Mo), spread on elemental titanium and Ti-64Al alloy. Nb and Mo are used as powder form to increase the contact surface and to improve the distribution. Both Mo and Nb are distributed on samples of Ti and Ti-64Al at 1100 °C and 1200 °C for 3 h. They were performed to effect different experiments objectives. This work was achieved to improve some properties and microstructure of Ti and Ti-64Al surface, using optical microscopy and SEM and study some mechanical properties. The effects of temperature and the powder contents on the microstructure of Ti and Ti-64Al alloy, different phases and hardness value of Ti and Ti-64Al alloy were determined. Experimental results indicate that increasing the powder contents and/or the temperature, the α + β phases change to the equiaxed β lamellar structure. In particular, experiments in 1200 °C were created by diffusion α + β phases both equiaxed β phase laminar and α + β phase, thus meeting the objectives were established in the work. In addition, simulation results are used for comparison with the experimental results by DICTRA software.

Keywords: diffusion, powder metallurgy, titanium alloy, molybdenum, niobium

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5569 Enhancing Coping Strategies of Student: A Case Study of 'Choice Theory' Group Counseling

Authors: Warakorn Supwirapakorn

Abstract:

The purpose of this research was to study the effects of choice theory in group counseling on coping strategies of students. The sample consisted of 16 students at a boarding school, who had the lowest score on the coping strategies. The sample was divided into two groups by random assignment and then were assigned into the experimental group and the control group, with eight members each. The instruments were the Adolescent Coping Scale and choice theory group counseling program. The data collection procedure was divided into three phases: The pre-test, the post-test, and the follow-up. The data were analyzed by repeated measure analysis of variance: One between-subjects and one within-subjects. The results revealed that the interaction between the methods and the duration of the experiment was found statistically significant at 0.05 level. The students in the experimental group demonstrated significantly higher at 0.05 level on coping strategies score in both the post-test and the follow-up than in the pre-test and the control group. No significant difference was found on coping strategies during the post-test phase and the follow-up phase of the experimental group.

Keywords: coping strategies, choice theory, group counseling, boarding school

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5568 DNA Barcoding Application in Study of Icthyo- Biodiversity in Rivers of Pakistan

Authors: Asma Karim

Abstract:

Fish taxonomy plays a fundamental role in the study of biodiversity. However, traditional methods of fish taxonomy rely on morphological features, which can lead to confusion due to great similarities between closely related species. To overcome this limitation, modern taxonomy employs DNA barcoding as a species identification method. This involves using a short standardized mitochondrial DNA region as a barcode, specifically a 658 base pair fragment near the 5′ ends of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene, to exploit the diversity in this region for identification of species. To test the effectiveness and reliability of DNA barcoding, 25 fish specimens from nine different fish species found in various rivers of Pakistan were identified morphologically using a dichotomous key at the start of the study. Comprising nine freshwater fish species, including Mystus cavasius, Mystus bleekeri, Osteobrama cotio, Labeo rohita, Labeo culbasu, Labeo gonius, Cyprinus carpio, Catla catla and Cirrhinus mrigala from different rivers of Pakistan were used in the present study. DNA was extracted from one of the pectoral fins and a partial sequence of CO1 gene was amplified using the conventional PCR method. Analysis of the barcodes confirmed that genetically identified fishes were the same as those identified morphologically at the beginning of the study. The sequences were also analyzed for biodiversity and phylogenetic studies. Based on the results of the study, it can be concluded that DNA barcoding is an effective and reliable method for studying biodiversity and conducting phylogenetic analysis of different fish species in Pakistan.

Keywords: DNA barcoding, fresh water fishes, taxonomy, biodiversity, Pakistan

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5567 Transformation of Aluminum Unstable Oxyhydroxides in Ultrafine α-Al2O3 in Presence of Various Seeds

Authors: T. Kuchukhidze, N. Jalagonia, Z. Phachulia, R. Chedia

Abstract:

Ceramic obtained on the base of aluminum oxide has wide application range, because it has unique properties, for example, wear-resistance, dielectric characteristics, exploitation ability at high temperatures and in corrosive atmosphere. Low temperature synthesis of α-Al2O3 is energo-economical process and it is actual for developing technologies of corundum ceramics fabrication. In the present work possibilities of low temperature transformation of oxyhydroxides in α-Al2O3, during a presence of small amount of rare–earth elements compounds (also Th, Re), have been discussed. Aluminium unstable oxyhydroxides have been obtained by hydrolysis of aluminium isopropoxide, nitrates, sulphate, chloride in alkaline environment at 80-90ºC tempertures. β-Al(OH)3 has been received from aluminium powder by ultrasonic development. Drying of oxyhydroxide sol has been conducted with presence of various types seeds, which amount reaches 0,1-0,2% (mas). Neodymium, holmium, thorium, lanthanum, cerium, gadolinium, disprosium nitrates and rhenium carbonyls have been used as seeds and they have been added to the sol specimens in amount of 0.1-0.2% (mas) calculated on metals. Annealing of obtained gels is carried out at 70 – 1100ºC for 2 hrs. The same specimen transforms in α-Al2O3 at 1100ºC. At this temperature in case of presence of lanthanum and gadolinium transformation takes place by 70-85%. In case of presence of thorium stabilization of γ-and θ-phases takes place. It is established, that thorium causes inhibition of α-phase generation at 1100ºC, at the time in all other doped specimens α-phase is generated at lower temperatures (1000-1050ºC). During the work the following devices have been used: X-ray difractometer DRON-3M (Cu-Kα, Ni filter, 2º/min), High temperature vacuum furnace OXY-GON, electronic scanning microscopes Nikon ECLIPSE LV 150, NMM-800TRF, planetary mill Pulverisette 7 premium line, SHIMADZU Dynamic Ultra Micro Hardness Tester, DUH-211S, Analysette 12 Dyna sizer.

Keywords: α-Alumina, combustion, phase transformation, seeding

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5566 Studies on Structural and Electrical Properties of Lanthanum Doped Sr₂CoMoO₆₋δ System

Authors: Pravin Kumar, Rajendra K. Singh, Prabhakar Singh

Abstract:

A widespread research work on Mo-based double perovskite systems has been reported as a potential application for electrode materials of solid oxide fuel cells. Mo-based double perovskites studied in form of B-site ordered double perovskite materials, with general formula A₂B′B″O₆ structured by alkaline earth element (A = Sr, Ca, Ba) and heterovalent transition metals (B′ = Fe, Co, Ni, Cr, etc. and B″ = Mo, W, etc.), are raising a significant interest as potential mixed ionic-electronic conductors in the temperature range of 500-800 °C. Such systems reveal higher electrical conductivity, particularly those assigned in form of Sr₂CoMoO₆₋δ (M = Mg, Mn, Fe, Co, Ni, Zn etc.) which were studied in different environments (air/H₂/H₂-Ar/CH₄) at an intermediate temperature. Among them, the Sr₂CoMoO₆₋δ system is a potential candidate as an anode material for solid oxide fuel cells (SOFCs) due to its better electrical conductivity. Therefore, Sr₂CoMoO₆₋δ (SCM) system with La-doped on Sr site has been studied to discover the structural and electrical properties. The double perovskite system Sr₂CoMoO₆₋δ (SCM) and doped system Sr₂-ₓLaₓCoMoO₆₋δ (SLCM, x=0.04) were synthesized by the citrate-nitrate combustion synthesis route. Thermal studies were carried out by thermo-gravimetric analysis. Phase justification was confirmed by powder X-ray diffraction (XRD) as a tetragonal structure with space group I4/m. A minor phase of SrMoO₄ (s.g. I41/a) was identified as a secondary phase using JCPDS card no. 85-0586. Micro-structural investigations revealed the formation of uniform grains. The average grain size of undoped (SCM) and doped (SLCM) compositions was calculated by a linear intercept method and found to be ⁓3.8 μm and 2.7 μm, respectively. The electrical conductivity of SLCM is found higher than SCM in the air within the temperature range of 200-600 °C. SLCM system was also measured in reducing atmosphere (pure H₂) in the temperature range 300-600 °C. SLCM has been showed the higher conductivity in the reducing atmosphere (H₂) than in air and therefore it could be a promising anode material for SOFCs.

Keywords: double perovskite, electrical conductivity, SEM, XRD

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5565 Two-Phase Flow Modelling and Numerical Simulation for Waterflooding in Enhanced Oil Recovery

Authors: Peña A. Roland R., Lozano P. Jean P.

Abstract:

The waterflooding process is an enhanced oil recovery (EOR) method that appears tremendously successful. This paper shows the importance of the role of the numerical modelling of waterflooding and how to provide a better description of the fluid flow during this process. The mathematical model is based on the mass conservation equations for the oil and water phases. Rock compressibility and capillary pressure equations are coupled to the mathematical model. For discretizing and linearizing the partial differential equations, we used the Finite Volume technique and the Newton-Raphson method, respectively. The results of three scenarios for waterflooding in porous media are shown. The first scenario was estimating the water saturation in the media without rock compressibility and without capillary pressure. The second scenario was estimating the front of the water considering the rock compressibility and capillary pressure. The third case is to compare different fronts of water saturation for three fluids viscosity ratios without and with rock compressibility and without and with capillary pressure. Results of the simulation indicate that the rock compressibility and the capillary pressure produce changes in the pressure profile and saturation profile during the displacement of the oil for the water.

Keywords: capillary pressure, numerical simulation, rock compressibility, two-phase flow

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5564 Leadership Values in Succession Processes

Authors: Peter Heimerl, Alexander Plaikner, Mike Peters

Abstract:

Background and Significance of the Study: Family-run businesses are a decisive economic factor in the Alpine tourism and leisure industry. Within the next years, it is expected that a large number of family-run small and medium-sized businesses will transfer ownership due to demographic developments. Four stages of succession processes can be identified by several empirical studies: (1) the preparation phase, (2) the succession planning phase, (3) the development of the succession concept, (4) and the implementation of the business transfer. Family business research underlines the importance of individual's and family’s values: Especially leadership values address mainly the first phase, which strongly determines the following stages. Aim of the Study: The study aims at answering the following research question: Which leadership values are dominating during succession processes in family-run businesses in Austrian Alpine tourism industry? Methodology: Twenty-two problem-centred individual interviews with 11 transferors and their 11 transferees were conducted. Data analysis was carried out using the software program MAXQDA following an inductive approach to data coding. Major Findings: Data analysis shows that nine values particularly influence succession processes, especially during the vulnerable preparation phase. Participation is the most-dominant value (162 references). It covers a style of cooperation, communication, and controlling. Discipline (142) is especially prevailing from the transferor's perspective. It addresses entrepreneurial honesty and customer orientation. Development (138) is seen as an important value, but it can be distinguished between transferors and transferees. These are mainly focused on strategic positioning and new technologies. Trust (105) is interpreted as a basic prerequisite to run the family firm smoothly. Interviewees underline the importance to be able to take a break from family-business management; however, this is only possible when openness and honesty constitute trust within the family firm. Loyalty (102): Almost all interviewees perceive that they can influence the loyalty of the employees through their own role models. A good work-life balance (90) is very important to most of the transferors, especially for their employees. Despite the communicated importance of a good work-life-balance, but however, mostly the commitment to the company is prioritised. Considerations of regionality (82) and regional responsibility are also frequently raised. Appreciation (75) is of great importance to both the handover and the takeover generation -as appreciation towards the employees in the company and especially in connection with the family. Familiarity (66) and the blurring of the boundaries between private and professional life are very common, especially in family businesses. Familial contact and open communication with employees which is mentioned in almost all handing over. Conclusions: In the preparation phase of succession, successors and incumbents have to consider and discuss their leadership and family values of family-business management. Quite often, assistance is needed to commonly and openly discuss these values in the early stages of succession processes. A large majority of handovers fail because of these values. Implications can be drawn to support family businesses, e.g., consulting initiatives at chambers of commerce and business consultancies must address this problem.

Keywords: leadership values, family business, succession processes, succession phases

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5563 Phytochemical Screening and Identification of Anti-Biological Activity Properties of Pelargonium graveolens

Authors: Anupalli Roja Rani, Saraswathi Jaggali

Abstract:

Rose-scented geranium (Pelargonium graveolens L’Hér.) is an erect, much-branched shrub. It is indigenous to various parts of southern Africa, and it is often called Geranium. Pelargonium species are widely used by traditional healers in the areas of Southern Africa by Sotho, Xhosa, Khoi-San and Zulus for its curative and palliative effects in the treatment of diarrhea, dysentery, fever, respiratory tract infections, liver complaints, wounds, gastroenteritis, haemorrhage, kidney and bladder disorders. We have used Plant materials for extracting active compounds from analytical grades of solvents methanol, ethyl acetate, chloroform and water by a soxhlet apparatus. The phytochemical screening reveals that extracts of Pelargonium graveolens contains alkaloids, glycosides, steroids, tannins, saponins and phenols in ethyl acetate solvent. The antioxidant activity was determined using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) bleaching method and the total phenolic content in the extracts was determined by the Folin–Ciocalteu method. Due to the presence of different phytochemical compounds in Pelargonium the anti-microbial activity against different micro-organisms like E.coli, Streptococcus, Klebsiella and Bacillus. Fractionation of plant extract was performed by column chromatography and was confirmed with HPLC analysis, NMR and FTIR spectroscopy for the compound identification in different organic solvent extracts.

Keywords: Pelargonium graveolens L’Hér, DPPH, micro-organisms, HPLC analysis, NMR, FTIR spectroscopy

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5562 Potentiostatic Electrodeposition of Cu₂O Films as P-Type Electrode at Room Temperature

Authors: M. M. Moharam, E. M. Elsayed, M. M. Rashad

Abstract:

Single phase Cu₂O films have been prepared via an electrodeposition technique onto ITO glass substrates at room temperature. Likewise, Cu₂O films were deposited using a potentiostatic process from an alkaline electrolyte containing copper (II) nitrate and 1M sodium citrate. Single phase Cu₂O films were electrodeposited at a cathodic deposition potential of 500mV for a reaction period of 90 min, and pH of 12 to yield a film thickness of 0.49 µm. The mechanism for nucleation of Cu₂O films was found to vary with deposition potential. Applying the Scharifker and Hills model at -500 and -600 mV to describe the mechanism of nucleation for the electrochemical reaction, the nucleation mechanism consisted of a mix between instantaneous and progressive growth mechanisms at -500 mV, while above -600 mV the growth mechanism was instantaneous. Using deposition times from 30 to 90 min at -500 mV deposition potential, pure Cu2O films with different microstructures were electrodeposited. Changing the deposition time from 30 to 90 min varied the microstructure from cubic to more complex polyhedra. The transmittance of electrodeposited Cu₂O films ranged from 20-70% in visible range, and samples exhibited a 2.4 eV band gap. The electrical resistivity for electrodeposited Cu₂O films was found to decrease with increasing deposition time from 0.854 x 105 Ω-cm at 30 min to 0.221 x 105 Ω-cm at 90 min without any thermal treatment following the electrodeposition process.

Keywords: Cu₂O, electrodeposition, film thickness, characterization, optical properties

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5561 Characterization of a Newfound Manganese Tungstate Mineral of Hübnerite in Turquoise Gemstone from Miduk Mine, Kerman, Iran

Authors: Zahra Soleimani Rad, Fariborz Masoudi, Shirin Tondkar

Abstract:

Turquoise is one of the most well-known gemstones in Iran. The mineralogy, crystallography, and gemology of Shahr-e-Babak turquoise in Kerman were investigated and the results are presented in this research. The Miduk porphyry copper deposit is positioned in the Shahr-Babak area in Kerman province, Iran. This deposit is located 85 km NW of the Sar-Cheshmeh porphyry copper deposit. Preliminary mineral exploration was carried out from 1967 to 1970. So far, more than fifty diamond drill holes, each reaching a maximum depth of 1013 meters, have provided evidence supporting the presence of significant and promising porphyry copper mineralization at the Miduk deposit. The mineral deposit harbors a quantity of 170 million metric tons of ore, characterized by a mean composition of 0.86% copper (Cu), 0.007% molybdenum (Mo), 82 parts-per-billion gold (Au), and 1.8 parts-per-million silver (Ag). The Supergene enrichment layer, which constitutes the predominant source of copper ore, exhibits an approximate thickness of 50 meters. Petrography shows that the texture is homogeneous. In terms of a gemstone, greasy luster and blue color are seen, and samples are similar to what is commonly known as turquoise. The geometric minerals were detected in XRD analysis by analyzing the data using the x-pert software. From the mineralogical point of view; the turquoise gemstones of Miduk of Kerman consist of turquoise, quartz, mica, and hübnerite. In this article, to our best knowledge, we are stating the hübnerite mineral identified and seen in the Persian turquoise. Based on the obtained spectra, the main mineral of the Miduk samples from the six members of the turquoise family is the turquoise type with identical peaks that can be used as a reference for identification of the Miduk turquoise. This mineral is structurally composed of phosphate units, units of Al, Cu, water, and hydroxyl units, and does not include a Fe unit. In terms of gemology, the quality of a gemstone depends on the quantity of the turquoise phase and the amount of Cu in it according to SEM and XRD analysis.

Keywords: turquoise, hübnerite, XRD analysis, Miduk, Kerman, Iran

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5560 Chemopreventive and Therapeutic Efficacy of Salsola inermis Extract against N-Nitrosodiethylamine-Initiated and Phenobarbital-Promoted Hepatocellular Carcinogenesis in Wistar Rats

Authors: Ahlam H. Mahmoud, Samir F. Zohny, Ibrahim H. Boraia, Faten S. Bayoumic, Eman Eissa

Abstract:

Hepatocellular carcinoma is one of the most common cancers worldwide and is known to be resistant to conventional chemotherapy. Therefore, we aimed to assess the Salsola inermis extract as a novel chemopreventive and/or therapeutic agent against N-nitrosodiethylamine (DNE)/phenobarbital (PB)-induced hepatocarcinogenesis in rats. Adult male Wistar albino rats were divided into five groups: group1 rats were served as normal controls; group 2 rats were injected intraperitoneally with S. inermis extract (100 mg/kg body weight/day) for 20 weeks; group 3 rats were subjected to two-phase hepatocarcinogenic regimen (initiation of hepatocarcinogenesis was performed by a single intraperitoneal injection of DEN at a dose of 200 mg/kg body weight, 2 weeks later, the carcinogenic effect was promoted by supplementation of rats with 0.05% PB for 16 weeks); group 4 rats were injected intraperitoneally with S. inermis extract 2 weeks prior to the injection of DEN, the daily injection of S. inermis extract was then continued for 18 weeks along with two-phase hepatocarcinogenic regimen (chemoprevention group); and group 5 rats were subjected to the two-phase hepatocarcinogenic regimen, and then, the animals were injected intraperitoneally with S. inermis extract for 4 weeks (treatment group). The activities of serum liver enzymes and levels of total bilirubin, conjugated bilirubin, α-fetoprotein, vascular endothelial growth factor (VEGF) and soluble intercellular adhesion molecule-1 (sICAM-1) in serum were decreased in chemopreventive and treated rats compared with DEN/PB-administered rats. Interestingly, the serum levels of total protein and albumin were normalized in chemopreventive and treated rats. Moreover, the majority of chemopreventive and treated rats showed an almost normal histological pattern of liver. In conclusion, S. inermis extract possessed chemopreventive and therapeutic activities against hepatocarcinogenesis in rats partially through the inhibition of VEGF and sICAM-1.

Keywords: Salsola inermis extract, hepatocarcinogenesis, α–fetoprotein, VEGF, sICAM-1

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5559 Polar Nanoregions in Lead-Free Relaxor Ceramics: Unveiling through Impedance Spectroscopy

Authors: Mohammed Mesrar, Hamza El Malki, Hamza Mesrar

Abstract:

In this study, ceramics of (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3 were synthesized through a conventional calcination process (solid-state method) at 1000°C for 4 hours, with x(%) values ranging from 0.0 to 100. Room temperature XRD patterns confirmed the phase formation of the samples. The Rietveld refinement method was employed to verify the morphotropic phase boundary (MPB) at x(%)=16-20. We investigated the average crystallite size and lattice strain using Scherrer's formula and Williamson-Hall (W-H) analysis. SEM image analyses provided additional evidence of the impact of doping on structural growth under low temperatures. Relaxation time extracted from Z″(f) and M″(f) spectra for x(%) = 0.0, 12, 16, 20, and 30 followed the Arrhenius law, revealing the presence of three distinct relaxation mechanisms with varying activation energies. The shoulder response in M″(f) indirectly indicated the existence of highly polarizable entities in the samples, serving as a signature of polar nanoregions (PNRs) within the grains.In this study, ceramics of (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3 were synthesized through a conventional calcination process (solid-state method) at 1000°C for 4 hours, with x(%) values ranging from 0.0 to 100. Room temperature XRD patterns confirmed the phase formation of the samples. The Rietveld refinement method was employed to verify the morphotropic phase boundary (MPB) at x(%)=16-20. We investigated the average crystallite size and lattice strain using Scherrer's formula and Williamson-Hall (W-H) analysis. SEM image analyses provided additional evidence of the impact of doping on structural growth under low temperatures. Relaxation time extracted from Z″(f) and M″(f) spectra for x(%) = 0.0, 12, 16, 20, and 30 followed the Arrhenius law, revealing the presence of three distinct relaxation mechanisms with varying activation energies. The shoulder response in M″(f) indirectly indicated the existence of highly polarizable entities in the samples, serving as a signature of polar nanoregions (PNRs) within the grains.

Keywords: (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3, Rietveld refinement, Scanning electron microscopy (SEM), Williamson-Hall plots, charge density distribution, dielectric properties

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5558 Honey Bee (Apis Mellifera) Drone Flight Behavior Revealed by Radio Frequency Identification: Short Trips That May Help Drones Survey Weather Conditions

Authors: Vivian Wu

Abstract:

During the mating season, honeybee drones make mating fights to congregation areas where they face fierce competition to mate with a queen. Drones have developed distinct anatomical and functional features in order to optimize their chances of success. Flight activities of western honeybee (Apis mellifera) drones and foragers were monitored using radio frequency identification (RFID) to test if drones have also developed distinct flight behaviors. Drone flight durations showed a bimodal distribution dividing the flights into short flights and long flights while forager flight durations showed a left-skewed unimodal distribution. Interestingly, the short trips occurred prior to the long trips on a daily basis. The first trips of the day the drones made were primarily short trips, and the distribution significantly shifted to long trips as the drones made more trips. In contrast, forager trips showed no such shift of distribution. In addition, drones made short trips but no long mating trips on days associated with a significant drop in temperature and increase of clouds compared to the previous day. These findings suggest that drones may have developed a unique flight behavior making short trips first to survey the weather conditions before flying out to the congregation area to pursue a successful mating.

Keywords: apis mellifera, drone, flight behavior, weather, RFID

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5557 The Clustering of Multiple Sclerosis Subgroups through L2 Norm Multifractal Denoising Technique

Authors: Yeliz Karaca, Rana Karabudak

Abstract:

Multifractal Denoising techniques are used in the identification of significant attributes by removing the noise of the dataset. Magnetic resonance (MR) image technique is the most sensitive method so as to identify chronic disorders of the nervous system such as Multiple Sclerosis. MRI and Expanded Disability Status Scale (EDSS) data belonging to 120 individuals who have one of the subgroups of MS (Relapsing Remitting MS (RRMS), Secondary Progressive MS (SPMS), Primary Progressive MS (PPMS)) as well as 19 healthy individuals in the control group have been used in this study. The study is comprised of the following stages: (i) L2 Norm Multifractal Denoising technique, one of the multifractal technique, has been used with the application on the MS data (MRI and EDSS). In this way, the new dataset has been obtained. (ii) The new MS dataset obtained from the MS dataset and L2 Multifractal Denoising technique has been applied to the K-Means and Fuzzy C Means clustering algorithms which are among the unsupervised methods. Thus, the clustering performances have been compared. (iii) In the identification of significant attributes in the MS dataset through the Multifractal denoising (L2 Norm) technique using K-Means and FCM algorithms on the MS subgroups and control group of healthy individuals, excellent performance outcome has been yielded. According to the clustering results based on the MS subgroups obtained in the study, successful clustering results have been obtained in the K-Means and FCM algorithms by applying the L2 norm of multifractal denoising technique for the MS dataset. Clustering performance has been more successful with the MS Dataset (L2_Norm MS Data Set) K-Means and FCM in which significant attributes are obtained by applying L2 Norm Denoising technique.

Keywords: clinical decision support, clustering algorithms, multiple sclerosis, multifractal techniques

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