Study Of Different Methods Research Articles

Comparative Study of Different Methods of Synthesis and Their Effect on the Thermomechanical Properties of a Halogenated Epoxy-Based Flame-Retardant Resin.

The work presented in this paper deals with the comparative synthesis of diglycidyl ether-based tetrabromobisphenol-A(TBBPA) using both conventional and nonconventional methods in order to explore materials for better industrial applications with respect to effective yield, cost, and time consideration. The conventional method involved the polycondensation of TBBPA and epichlorohydrin in the presence of an alkali catalyst. The nonconventional routes adopted for the synthesis of the material involved ultrasonication, microwave irradiation, and UV light exposure. The Fourier transform infrared spectroscopy spectra of all the synthesized materials of the resin were found to be identical, and the X-ray diffraction analysis showed the material as amorphous. The mechanical studies of the resins revealed that all these resins synthesized by different methods are strong and possess high viscosity. Based on the overall thermal, rheological, and excellent hydrophobic properties, it can serve as an excellent flame retardant.

A review study on the structural and photoluminescence properties of rare earth doped lanthanate ALa2ZnO5 (A = Ca, Sr or Ba) phosphors

Rare earth doped phosphors are gaining much more attention attributed to their wide optoelectronic applications in the solid-state lighting, in fluorescent lamps, solar cells, display devices, temperature sensors etc. The structural and photoluminescent (PL) features of rare earth doped lanthanate compounds ALa2ZnO5 (A = Ca, Sr or Ba) are extensively explored by researchers owing to their better physical, chemical and luminescent properties. This review deals with the study of different methods used for the synthesis of bare and rare earth doped ALa2ZnO5 (A = Ca, Sr or Ba) phosphors. The solution combustion process has proved to be a better low temperature synthesis technique than the alternative methods such as solid state, sol-gel and co-precipitation methods etc. to get highly crystalline lanthanate phosphors. Structural analysis is also studied in detail to understand the different phases of rare earth doped CaLa2ZnO5, SrLa2ZnO5 and BaLa2ZnO5 phosphors. Apart from this, the PL properties of these rare earth doped lanthanate compounds are explained in depth. Their excitation, emission wavelength, lifetime and CIE coordinates are also provided for comparative studies along with their applications. Owing to the significant number of energy transitions of rare earth ions within the host lattice, these lanthanate phosphors have wide scope in different display fields. The reading of this review will be beneficial for researchers working in the field of phosphors.

Machine translation of English content: A comparative study of different methods

Abstract Based on neural machine translation, this article introduced the ConvS2S system and transformer system, designed a semantic sharing combined transformer system to improve translation quality, and compared the three systems on the NIST dataset. The results showed that the operation speed of the semantic sharing combined transformer system was the highest, reaching 3934.27 words per second; the BLEU value of the ConvS2S system was the smallest, followed by the transformer system and the semantic sharing combined transformer system. Taking NIST08 as an example, the BLEU values of the designed system were 4.74 and 1.49 higher than the other two systems. The analysis of examples showed that the semantic sharing combined transformer had higher translation quality. The experimental results show that the proposed system is reliable in English content translation and can be further promoted and applied in practice.

Optimization of Spectral Efficiency in Massive MIMO Network for Different Deployment Scenarios

Background: Spectrum efficiency is labelled to be the most discussed area of wireless communication. Today, wireless communication is one of the fastest developing fields due to which there is a tremendous increase in subscribers that leads to the demand for more spectrum. Though the growth in the spectrum is not possible but optimizing it is a good alternative. Methods: This paper provides a detailed study of different methods used for the optimization of spectrum efficiency in massive multiple inputs and outputs. The main goal of this paper is to findout how the spectrum could be used efficiently to meet user demands. It includes the technique of fixing specific parameters like coherent block length, number of reception antennas, pilots reuse factor, signal to noise ratio, and number of users to make more efficient use of the spectrum. This paper also explains the achievement of spectral efficiency under different deployment scenarios i.e., urban, suburban, and rural in ITU-R M.2135 standard. Results: As seen from the results, steep SEs are accomplished by making a schedule of many UE for mutual broadcast, while the SE per UE maybe 1-4 bit/s/Hz. These high-class demonstrations show that massive MIMO e.g an SNR of 0-5 dB with a limited pilot reuse factor of β= 3, and the fast techniques are applied for lessening the distortion noise and instrument damage. According to the simulations, it is found that massive MIMO with M = 100 can produce a 10×gain in SE in the IMT-Advanced requirements of 3 bit/s/Hz/cell. For the bigger sizes of antennas, M = 500 massive MIMO can even give 40×gain over IMT-Advanced. Conclusion: With the advancement of technology, the number of users is increasing tremendously, leading to a shortage of spectrum. Hence, the need of the hour is to make efficient use of the available spectrum while maintaining the Quality of service. Therefore, researchers have proposed specific methods that fulfill this need. The paper realizes the SE approach on different deployment scenarios like urban, suburban and rural in the ITU-R M.2135 standard and proves that under all the three scenarios, P-ZF remained unchanged. As seen from the results, steep SEs are accomplished by making a schedule of many UE for mutual broadcast, while the SE per UE maybe 1-4 bit/s/Hz. These high-class demonstrations show that massive MIMO likes an SNR of 0–5 dB with a limited pilot reuse factor of β= 3, and the fast techniques are applied for lessening the distortion noise from instrument damage. According to the simulations, it is seen that massive MIMO with M = 100 can produce a 10×gain in SE in the IMT-Advanced requirements of 3 bit/s/Hz/cell. For the bigger sizes of antennas, M = 500 massive MIMO can even give 40×gain over IMT-Advanced. The outcomes in this paper suggest the uncorrelated fading, although for decreasing inter-user interference, correlated fading is required, to raise large SE with less β. This study makes SE independent of topography. Furthermore, optimization of energy under different deployment scenarios, along with these simulations, can optimize the spectrum to a greater extent.

Comparative study of different methods of microscopy followed by a culture method in the detection of mycobacterium tuberculosis in clinically and radiologically suspected cases of pulmonary tuberculosis

To compare the sensitivity of 2 microscopic methods for the diagnosis of Mycobacterium tuberculosis (M.tb) along with culture and drug susceptibility testing to first line drugs.: The cross-sectional study comprises 200 suspected cases of pulmonary tuberculosis both clinically and radiologically in KIMS, Bangalore over a period of 2 years. Samples (sputum/BAL fluid) were collected, processed and stained by Ziehl Neelson (ZN) and Fluorescent methods. Culture and drug susceptibilty testing was done for Streptomycin, Isoniazid, Rifampicin and Ethambutol by Mycobacterium growth indicator tube (MGIT) method after decontamination.Fischer’s test : 1. Out of 200 samples: 1.120 were male and 80 were female; 2. 18 were positive by Ziehl Neelson, 21 by Fluorescent and 28 by culture; 3. Majority of the patients belonged to age group 41-50 years (23%); 4. InMGIT, 26 were M.tb and 2 were Non-tubercular mycobacteria; 5. Out of 26 M.tb isolates, 4 were resistant to streptomycin, 6 to isoniazid, 2 to rifampicin and 9 to ethambutol.1. The sensitivity of Fluorescent staining (64.28%) is higher than that of Ziehl-Neelson (51.7%); 2. In MGIT, 26 were M.tb and 2 were Non tubercular mycobacteria; 3. 2 were Multi-drug resistant- tuberculosis (MDR-TB) This study made us aware of the need for prompt detection, identification and appropriate treatment of Tuberculosis due to the rising incidence of MDR-TB.

Railway Safety and Security using Image Processing and IOT

The railways have become the primary form of transportation because of their capability and speed. Even a small improvement in this sector will aid the overall development of a nation. There are various reasons for abnormalities that occur on railway tracks which result in breakdowns and accidents. The poor maintenance of the railway tracks will also result in accidents. The important aspect we are considering in this paper is to avoid the crowd of passengers in each compartment considering the Covid-19 situation. Other aspects are avoiding accidents in foggy conditions, obstacles in front of railways, due to track faults. Comparative studies of different methods used in these aspects of railways are made and the best which gives better accuracy is considered for Implementation.

Cleaning Zirconia Surface Prior To Bonding: A Comparative Study of Different Methods and Solutions

To evaluate resin cement bond strength after removal of salivary contamination from a zirconia surface using different cleaning solutions and air-borne particle abrasion. One-hundred and twenty zirconia specimens (KATANA STML, Noritake) were prepared and divided into 12 groups (n = 10). Groups were subjected to a notched-edge shear bond strength test (ISO 29022) to analyze the bonding efficiency of a resin cement (Panavia V5, Kuraray Noritake Dental Inc.) before and after contamination with saliva. Group 1 (control) was prepared and cemented without salivary contamination. Group 2 was coated with ceramic primer (Clearfil Ceramic Primer Plus, Kuraray Noritake Dental Inc.) then subjected to salivary contamination then tested. Group 3 was contaminated, cleaned by air-borne particle abrasion, ceramic primer and resin cement applied, and tested. Groups 4 to 12 were contaminated, and then different cleaning solutions (water, 4.5% hydrofluoric acid, 35% phosphoric acid, Ivoclean, KATANA cleaner, Zirclean, sodium hypochlorite 4%, and 7.5%) were used to decontaminate the zirconia surface, followed by ceramic primer, resin cement application, and tested.One-way ANOVA and Tukey post-hoc analysis was used to analyze the data. One-way ANOVA showed statistical differences among cleaning procedures (p < 0.001, F = 13.48). Air-borne particle abrasion was the only group which provided a bond strength (21 ± 2.8 MPa) that was not statistically different than the control group in which no contamination occurred (25.3 ± 3.3 MPa) (p = 0.247). The use of hydrofluoric acid and zirconia cleaning solutions resulted in bond strengths values which were not statistically different from each other (17.5-19.1 MPa). Air-borne particle, zirconia cleaning solutions and hydrofluoric acid are feasible to decontaminate the zirconia surface from saliva prior to bonding the restoration.

Strategic Study of different Methods &amp; Materials used for Production of Activated Carbon

Strategic Study of different Methods &amp; Materials used for Production of Activated Carbon

Numerical study of different methods applied to the one-dimensional transient heat equation

This article aims to compare the results obtained by applying three numerical methods: Explicit Euler, Crank-Nicolson,and Multi-stage (R11), in the one-dimensional heat diffusion transient equation with different initial and boundary conditions. The discretization process was performed using the finite difference method. In order to guarantee the convergence of the methods used, consistency and stability were verified by Lax theorem. The results are presented in graphs and tables that contain the data of the analytical solution and the numerical solutions. It was observed that the results obtained by R11 method generated solutions with minor errors.

A comparative Study of Different Methods of Maxillary Incisors Intrusion(Cone Beam Study)

Aim: To compare, through cone-beam computed tomography (CBCT), the root resorption and treatment efficiency of two different mini-implant-assisted modalities in intruding the maxillary incisors. Subjects and Methods: The present study composed of 26 patients (males, females) aged between 12-18 years who had deep bite and elongated maxillary incisors. They were randomly selected and divided into two group: anterior mini-implant group (AMG) and posterior mini-implant group (PMG). In the AMG, approximately 40 g of force was applied per side with elastic chains and in the PMG, with beta-titanium wires. This study was conducted on CBCT scans taken before intrusion and after 18 weeks of intrusion. Result: The incisors showed a significant reduction in length and volume, this amount was greater in AMG than PMG. Significant changes in labial inclination of all incisors, which were greater in PMG than AMG. Conclusion: Posterior mini-implants assisted maxillary incisors intrusion is preferred than anterior mini-implant assisted maxillary incisor intrusion in case of upright position, as the use of such mechanics directs them to less root resorption and more labial tipping.

Prevalence study of different methods for hepatitis B virus diagnosis with blood donor people in Baghdad city

Background: Globally, infecting with hepatitis B virus (HBV) is a big issue today. The present study was aimed to assess the prevalence and year-wise trend of the HBV surfaces antigens (HBs-Ag), antibodies vs. HBV core antigens (anti-HBcs) while HBV-DNA in serum sample patients and replacement blood donors in Baghdad, Iraq. Methods: During the period between 2017 and 2019, a total of 212 blood donors of ages 18–70 years were screened for HBs-Ag, anti-HBs by enzyme-linked immunosorbent assay (ELISA) technique, and anti-HBc antigen–antibody (Ag–Ab) and HBV-DNA using real-time PCR. Results: A total of 110 (51.8%) of 212 blood donors were positive to all tests: HBs-Ag, anti-Hbs, anti-HBc and HBV-DNA. Forty-six (41.8%) were positive for HBV-DNA, HBs-Ag and anti-HBc, whereas 14 (12.7%) were positive for HBs-Ag and anti-HBc. Although nine (8.1%) blood donors were positive in real-time PCR (HBV-DNA loaded) with a negative result in ELISA. Forty one (37.2%) markers indicated a high number of inveterate or resolvable contagion. The total diffusion increment significance in 2017–2018, stabilized thereafter and started decreasing from 2018 to 2019 marginally. There is a high significance variance at (P < 0.01) while comparison among examined groups. Conclusions: Significance and impact of study: the prevalence of HBV infection in 3 years is lower in Baghdad blood donors (51.8%) compared to other regions of Iraq. A high number of infections with no signs of HBs-Ag or viral DNA were recorded. Therefore, the inclusion of anti-HBc seromarker and DNA in the routine screening could isolate potential infectious blood units.

OVERVIEW ON METHODS OF SYNTHESIS OF NANOPARTICLES

In recent years, interest in the development of novel drug delivery systems using nanoparticles has gained more attention. The nanoparticles offer several advantages over other conventional drug delivery systems. Nanoparticles have gained importance in technological advancements due to their modifiable physical, chemical and biological properties with improved performance over their bulk foils. Nanoparticles can simply move in the body due to their small size and reach very complex organs through diverse routes. The high stability, controlled drug release makes nanoparticles the most suitable drug delivery system. Along with all these advantages, they offer variety in routes of administration. Both hydrophilic, as well as hydrophobic drugs, can be delivered in the form of nanoparticles. Nanoparticles have been used as a physical approach to modify and advance the pharmacokinetics and pharmacodynamics possessions of various types of drug molecules. Thesol-gel technique is a stress-free and very inexpensive process to formulate metal oxides and permits control over the doping process or adding of transition metals, as related to other research techniques. The study of different methods of synthesis of nanoparticles is essential to obtain desired nanoparticles with specific sizes and shapes. They are suitable candidates for various marketable and local applications, which include imaging, catalysis medical applications and environmental applications. This review mainly focuses on approaches used for the production of nanoparticles and different methods of synthesis of nanoparticles such as physical, chemical and biological method.

Research and analysis of methods for preventing silver alloys from tarnishing

This paper examines factors causing the darkening of items made of silver alloys in showcases and storehouses of museums, the authors analyze methods to prevent this undesirable process. The results of studies of different methods for preventing tarnishing of silver alloys are also presented.

Assessment of different solution methods for receding contact problems in functionally graded layered mediums

This paper presents a comparative study of different methods, such as the analytical method, finite element method (FEM), and multilayer perceptron (MLP) for analyzing a frictionless receding contact problem. The problem consists of two layers resting on a Winkler foundation. The top layer is functionally graded (FG) along the depth and pressed using a rigid cylindrical stamp, whereas the bottom layer is homogeneous. We assumed that the contact between the two layers, and that between the FG layer and the rigid cylindrical stamp are frictionless; additionally, compressive normal tractions can be transmitted through the interface. First, the problem was solved analytically using the theory of elasticity and integral transform techniques. Second, the finite element solution of the problem was obtained using ANSYS software. Finally, the problem was extended based on the MLP, which an artificial neural network used for different problem parameters. The results of this study showed that the variations in the contact lengths at the interface between the rigid cylindrical stamp and the FG layer, those between the homogeneous layer and the FG layer, and the maximum contact pressures at these interfaces depended on various dimensionless quantities such as the stamp radius, stiffness parameter, shear modulus ratio, and elastic spring constant ratio. We observed that the results obtained with the three different methods, namely the analytical method, FEM, and MLP, are extremely compatible with each other, thus proving the accuracy of these results.

Оценка эффективности выездного налогового контроля на основе оптимальной системы качественных показателей

The study of different methods for assessment the effectiveness of tax control shows that the same quantitative indicators characterizing the results of tax audits are used. However, the authors group them into a system in different ways and give them definitions and interpretation with some degree of variability. Some of them pay attention to the development of general indicator, while others offer systematic approach. Therefore, the question of creating an optimal system of indicators remains. In this article, the author proposes and justifies a system of indicators that will allow quickly determine the effectiveness of both the on-site control of the tax inspectorate and the control activities in general.

Development of a Typical Urban Driving Cycle for Battery Electric Vehicles Based on Kernel Principal Component Analysis and Random Forest

Great concerns have been raised on the driving cycle due to its critical importance in vehicle design, energy management strategy, and energy consumption forecast of new energy vehicles. Taking Xi'an city as a case, a novel method of driving cycle development for battery electric vehicles is proposed in this paper. First, the chase car method and on-board measurement method are combined to collect sufficient real driving data, which are randomly divided into two parts for developing and validating the target cycle. Then the nonlinear dimension reduction of characteristic parameters with respect to the micro-trips is achieved by employing kernel principal component analysis, and an improved clustering method is developed for constructing candidate cycles, in which the K-means clustering algorithm is applied in the training of random forest. The target cycle is selected from the candidate cycles by determining the assessment criteria with consideration of the characteristic parameters and the speed-acceleration distribution probability. Finally, a comparative study of different methods is implemented to illustrate the effectiveness of the proposed method. The typicality of the target cycle is revealed by analyzing the discrepancies between the target cycle and other legislative cycles.

Qualitative and Comparative Study of Different Methods of Interpolation for the Mapping of Groundwater Salinity: Case Study of Thermal Waters Used for Irrigation in Northeastern Algeria

Faced with the scarcity of surface water accentuated by climate change, particularly in many arid and semi-arid countries, the quality of groundwater used for irrigation is a concern to agronomists and hydrogeologists. When these waters are of deep origin, they may have high mineralization and chemical compositions unsuitable for irrigation; in particular, they may alter soils and crops. It is therefore important to optimize the spatial estimation of the salinity of these waters and contribute to better knowledge of their quality, through an adapted and robust statistical and geostatistical approach. In the case of north-eastern Algeria, the objective of this study is to characterize the quality of deep waters and to test two interpolation methods (Inverse distance weight and ordinary Kriging) of their electrical conductivity (EC) as an indicator of their salinity and of the risk of damaging irrigated soils. 51 groundwater samples were taken in this region where there are many thermal springs, the water of which is used for irrigation and often is highly mineralized (EC between 0.6 and 26.6 dS/m). The geology is composed of karstic rocks crossed by large faults that allow deep water to rise. Based on major elements contents, analysis of the hydrochemical facies of these waters shows that the main facies are hyperchlorinated sodium (38%) and sulfated calcium (32%). The RSC (Residual Sodium Carbonate) and SAR (Irrigation water salt) indexes were used to assess the water quality. The results indicate that the majority of the sampled groundwater present a risk for soils irrigated with these waters (almost 1/3 presents a strong risk). The risk for the soils seems to be explained by the positive value of the residual alkalinity, and the high risks of sodization and alkalinization. The geostatistical analysis reveals strong heterogeneity in electrical conductivity (salinity). The maps based on this analysis allow the identification of risk areas. The comparison of Inverse distance weight and ordinary Kriging methods indicates similar results being obtained through both methods. However, ordinary kriging appears to be more accurate, less biased, and seemingly better represents the organization of the groundwater resources, as NE-SW alignments are visible. With the proposed approach, it is possible to calculate the surface areas of the different salinity thresholds and then optimize the use of deep groundwater for irrigation.

Accurate Multilevel Classification for Wildlife Images.

The most common approaches for classification rely on the inference of a specific class. However, every category could be naturally organized within a taxonomic tree, from the most general concept to the specific element, and that is how human knowledge works. This representation avoids the necessity of learning roughly the same features for a range of very similar categories, and it is easier to understand and work with and provides a classification for each abstraction level. In this paper, we carry out an exhaustive study of different methods to perform multilevel classification applied to the task of classifying wild animals and plant species. Different convolutional backbones, data setups, and ensembling techniques are explored to find the model which provides the best performance. As our experimentation remarks, in order to achieve the best performance on the datasets that are arranged in a tree-like structure, the classifier must feature an EfficientNetB5 backbone with an input size of 300 × 300 px, followed by a multilevel classifier. In addition, a Multiscale Crop data augmentation process must be carried out. Finally, the accuracy of this setup is a 62% top-1 accuracy and 88% top-5 accuracy. The architecture could benefit for an accuracy boost if it is involved in an ensemble of cascade classifiers, but the computational demand is unbearable for any real application.

Investigations on scheduling algorithms in LTE-advanced networks with carrier aggregation

Third generation partnership project (3GPP) long-term evolution advanced (LTE-A) is the fastest growing technology, which supports variety of applications by using effective and efficient radio resource management (RRM) procedure. With carrier aggregation (CA) concepts included in LTE-advanced protocol, the complexity of the RRM and scheduling of data increases. In this paper, basic LTE-A concepts and a study of different methods of component carrier allocation is studied and performance evaluation is carried out. From the simulation results, it can be inferred that static methods of component carrier allocation is simple but it could not be able to satisfy various important scheduler metric to provide a better QoS to UE. The random method though for some cases it seen better but it is not reliable as the outputs are also random. The dynamic methods of component carrier allocation have been able to provide better scheduler performance metric compared to static and random methods. More over different dynamic approaches can be also combined to improve the overall system efficiency.

Estimation and Testing Procedures for the Reliability Characteristics of Chen Distribution Based on Type II Censoring and the Sampling Scheme of Bartholomew

In this paper, we consider Chen distribution and derive UMVUEs and MLEs of the parameter λ , hazard rate h(t) and the two measures of reliability, namely R(t) = P(X &gt; t), where X denotes the lifetime of an item and P = P(X &gt; Y ), which represents the reliability of an item or system of random strength X subject to random stress Y , under type II censoring scheme and the sampling scheme of Bartholomew . We also develop interval estimates of the reliability measures. Testing procedures for the hypotheses related to different parametric functions have also been developed. A comparative study of different methods of point estimation and average confiddence length has been done through simulation studies. The analysis of a real data set is presented for illustration purpose.