bluuebunny/crossref_metadata_2025 huggingface dataset:
Description of the algorithms for testing the horizontal jump in a computerized testing system of gross motor skills
Authors: Moraes Arina Bragança , Chebbi Brahim , Tremblay Line , Thorpe Moriah , Theriault Francis
Published: September 2021

Assessment of gross motor skills is important for children, youths, and adults and can be beneficial for the study and diagnosis of different health conditions. The classical tools are mainly administered by operators. A computerized system using sensors to assess gross motor skills could enhance these tools, providing consistency of measurement, reduce human error, and automate data collection. As part of a computerized system to measure gross motor skills using the Kinect™, we present the details of algorithms developed to test the “horizontal jump” (HJ). These algorithms were developed by translating the performance criteria into equations for the coordinates of anatomical landmarks, describing the expected kinematic behaviour of relevant body parts. Our test results show that the algorithms successfully evaluated the performance criteria.
Enhanced Photocatalytic Activity of Reduced Graphene Oxide/Bismuth Sulfide Nanostructure Composites for the Degradation of Methylene Blue
Authors: Chufa Bayisa Meka , Gonfa Bedasa Abdisa , Anshebo Teketel Yohannes
Published: September 2021

Today, the issue of the environment is the concern of scientists worldwide. Aside from developed countries, developing countries are revolutionizing their economy from agriculture to industries, aggravating the discharge of pollutants. Textile industries are the main sources of pollutant dyes such as methylene blue (MB). In this study, a simple and green synthesis method was used to manufacture a nanostructure heterogeneous photocatalyst, rGO-Bi2S3, for the degradation of MB. Bi2S3 and rGO were synthesized separately using Vernonia amygdalina (VA) plant extract. rGO-Bi2S3 was synthesized using a single-step refluxed hydrothermal method. The products were characterized by XRD, FT-IR, UV-Vis, DTA, TGA, and visual techniques. The comparative degradability degree of the dye under visible light irradiation with and without the presence of the catalyst was studied. The performance test results showed 99% degradation of MB in the presence and 7% in the absence of the catalyst under the same condition for the duration of 25 minutes. The durability and reusability tests for the catalyst were also studied for five cycles. The maximum decrease in the degradation capacity of the catalyst for the duration of 25 minutes was 0.5%. Hence, rGO-Bi2S3 is found to be the ideal material for the degradation of MB, for environmental protection.
Trefoil Factor 3 Inhibits Thyroid Cancer Cell Progression Related to IL-6/JAK/STAT3 Signaling Pathway
Authors: Xin Yunchao , Shang Xiaoling , Sun Xiaoran , Liu Yachao , Xu Guogang , Xue Gang
Published: September 2021

Objectives. Abnormal expression of trefoil factor 3 (TFF3) in breast, stomach, and colon tumors may be related to the occurrence of tumors, suggesting its role in angiogenesis. In this study, the aim was to explore the role of TFF3 in thyroid cancer. Methods. TFF3 expression analysis was performed via GEPIA and RT-PCR. To explore the effects of TFF3 on thyroid cancer cell motility, cell function assays were performed. Furthermore, GSEA pathway analysis and western blot were used to explore the mechanism by which TFF3 represses the progression of thyroid cancer cells. Results. Here, we showed that low expression level of TFF3 in thyroid cancer is related to thyroid cancer nodal metastasis. The patients with low TFF3 expression showed worse disease-free survival than those with high level of TFF3. Underexpressed TFF3 increased cell motility and inhibited cell apoptosis. We found that the levels of IL-6, p-JAK2/JAK2, and pSTAT3/STAT3 were inhibited in the pcDNA-TFF3 group compared to the pcDNA-NC group and these factors were upregulated in the si-TFF3 group compared to the si-NC group in BCPAP and TPC-1 cells. Conclusion. TFF3 inhibits thyroid cancer cell progression related to IL-6/JAK/STAT3 signaling pathway.
Immune Mechanism, Gene Module, and Molecular Subtype Identification of Astragalus Membranaceus in the Treatment of Dilated Cardiomyopathy: An Integrated Bioinformatics Study
Authors: Chen Xiao-yang , Han Hong-fei , He Zhen-yan , Xu Xue-gong
Published: September 2021

Astragalus membranaceus has complex components as a natural drug and has multilevel, multitarget, and multichannel effects on dilated cardiomyopathy (DCM). However, the immune mechanism, gene module, and molecular subtype of astragalus membranaceus in the treatment of DCM are still not revealed. Microarray information of GSE84796 was downloaded from the GEO database, including RNA sequencing data of seven normal cardiac tissues and ten DCM cardiac tissues. A total of 4029 DCM differentially expressed genes were obtained, including 1855 upregulated genes and 2174 downregulated genes. GO/KEGG/GSEA analysis suggested that the activation of T cells and B cells was the primary cause of DCM. WGCNA was used to obtain blue module genes. The blue module genes are primarily ADCY7, BANK1, CD1E, CD19, CD38, CD300LF, CLEC4E, FLT3, GPR18, HCAR3, IRF4, LAMP3, MRC1, SYK, and TLR8, which successfully divided DCM into three molecular subtypes. Based on the CIBERSORT algorithm, the immune infiltration profile of DCM was analyzed. Many immune cell subtypes, including the abovementioned immune cells, showed different levels of increased infiltration in the myocardial tissue of DCM. However, this infiltration pattern was not obviously correlated with clinical characteristics, such as age, EF, and sex. Based on network pharmacology and ClueGO, 20 active components of Astragalus membranaceus and 40 components of DMCTGS were obtained from TCMSP. Through analysis of the immune regulatory network, we found that Astragalus membranaceus effectively regulates the activation of immune cells, such as B cells and T cells, cytokine secretion, and other processes and can intervene in DCM at multiple components, targets, and levels. The above mechanisms were verified by molecular docking results, which confirmed that AKT1, VEGFA, MMP9, and RELA are promising potential targets of DCM.
Numerical Study of Fracture Characteristics of Deep Granite Induced by Blast Stress Wave
Authors: Zhu Zheming , Gao Weiting , Wan Duanying , Wang Meng , Shu Yun
Published: September 2021

To study the characteristics of rock fracture in deep underground under blast loads, some numerical models were established in AUTODYN code. Weibull distribution was used to characterize the inhomogeneity of rock, and a linear equation of state was applied to describe the relation of pressure and volume of granite elements. A new stress initialization method based on explicit dynamic calculation was developed to get an accurate stress distribution near the borehole. Two types of in situ stress conditions were considered. The effect of heterogeneous characteristics of material on blast‐induced granite fracture was investigated. The difference between 2D models and 3D models was discussed. Based on the numerical results, it can be concluded that the increase of the magnitude of initial pressure can change the mechanism of shear failure near the borehole and suppress radial cracks propagation. When initial lateral pressure is invariable, with initial vertical pressure rising, radial cracks along the acting direction of vertical pressure will be promoted, and radial cracks in other directions will be prevented. Heterogeneous characteristics of material have an obvious influence on the shear failure zones around the borehole.
Measuring Total Factor Productivity of China Provincial Non-Life Insurance Market: A DEA-Malmquist Index Method
Authors: Yu Fangping , Chen Hang , Luo Jiaqi , Kuang Haibo
Published: September 2021

The unbalanced economic development results in the difference in operating efficiency of the non-life insurance industry in China’s provinces; based on the DEA-Malmquist index method, this paper investigates the provincial differences, dynamic change characteristics, and causes of non-life insurance productivity in 31 provinces of China from 2004 to 2017. The results show that in the sample period, there are significant differences between provinces and regions in China’s non-life insurance efficiency, which generally shows the echelon spatial characteristics of “strong in the west and weak in the east”. Technological progress in the western region promotes the rapid growth of total factor productivity, while the low efficiency of technological progress in the eastern region restrains the improvement of total factor productivity. The overall total factor productivity of China’s provincial non-life insurance industry is on the rise, mainly due to the improvement of pure technical efficiency and scale efficiency, while technological progress has an inhibiting effect on the contrary. These conclusions are of reference value for relevant stakeholders in China’s provincial non-life insurance market to formulate development strategies and business strategies.
New Immunotherapeutic Approaches for Glioblastoma
Authors: Vázquez Cervantes Gustavo Ignacio , González Esquivel Dinora F. , Gómez-Manzo Saúl , Pineda Benjamín , Pérez de la Cruz Verónica
Published: September 2021

Glioblastoma (GBM) is the most common primary malignant brain tumor with a high mortality rate. The current treatment consists of surgical resection, radiation, and chemotherapy; however, the median survival rate is only 12–18 months despite these alternatives, highlighting the urgent need to find new strategies. The heterogeneity of GBM makes this tumor difficult to treat, and the immunotherapies result in an attractive approach to modulate the antitumoral immune responses favoring the tumor eradication. The immunotherapies for GMB including monoclonal antibodies, checkpoint inhibitors, vaccines, and oncolytic viruses, among others, have shown favorable results alone or as a multimodal treatment. In this review, we summarize and discuss promising immunotherapies for GBM currently under preclinical investigation as well as in clinical trials.
Design and Implementation of Nanotechnology QCA Geometric Greedy Router
Authors: Touil Lamjed , Gassoumi Ismail , Mtibaa Abdellatif
Published: September 2021

This paper presents an optimized geometric greedy router (GGR) based on quantum dot cellular automata (QCA) technology. The proposed structure of GGR is based on a spanning tree of the network. This type of communication does not require an IP address. It uses only local information and can be used in many communication devices. In this paper, we first describe the principal components of the router and then we present their QCA architecture. The QCA technology is the most likely alternative to replace conventional circuits (CMOS) due to their very low power consumption and high processing speed. To consider integration with other complex circuit, we have utilized QCA clock-phase-based technique for the proposed design architecture. The results obtained using the QCA designer tool exhibit the superiority of the presented architecture over the existing designs. The proposed structure shows a reduction of 30% reduction in occupied space. The power dissipation rate of the proposed design is analyzed by QCAPro tool to approve its reliability.
Dynamic Analysis and Hopf Bifurcation of a Lengyel–Epstein System with Two Delays
Authors: Li Long , Zhang Yanxia
Published: September 2021

In this paper, a Lengyel–Epstein model with two delays is proposed and considered. By choosing the different delay as a parameter, the stability and Hopf bifurcation of the system under different situations are investigated in detail by using the linear stability method. Furthermore, the sufficient conditions for the stability of the equilibrium and the Hopf conditions are obtained. In addition, the explicit formula determining the direction of Hopf bifurcation and the stability of bifurcating periodic solutions are obtained with the normal form theory and the center manifold theorem to delay differential equations. Some numerical examples and simulation results are also conducted at the end of this paper to validate the developed theories.
Diagnosis and Management of Acquired Hemophilia A: Case Reports and a Literature Review
Authors: Rinaldi Ikhwan , Prasetyawaty Findy , Fazlines Siti , Winston Kevin , Samudera Nurrobi Yusuf Aji , Leoni Jessica , Restu Tulus Maha Ilham Hidayat , Wicaksono Satrio , Wicaksono Abdillah Yasir , Aslani Averina Octaxena , Ikhsani Rizkania
Published: September 2021

Background. Acquired hemophilia A (AHA) is a potentially life-threatening autoimmune hemostatic disorder where autoantibodies that disrupt the functions of factor VIII (FVIII) are present in the circulation. The early diagnosis of AHA is difficult since the symptoms of AHA differ from those of congenital hemophilia A. Furthermore, the management of AHA is also more complex due to the presence of autoantibodies against FVIII (FVIII inhibitors). Here, we present three case reports and conduct a literature review of AHA with the aim to increase awareness and knowledge regarding the diagnosis and treatment of AHA. Case Presentations. We present three patients diagnosed with AHA in these case reports. The first patient was a young female, while the second and third patients were middle-aged and elderly males, respectively. All patients presented with a chief complaint of bruises without hemarthrosis and a history of bleeding. Laboratory examinations of the patients revealed isolated prolonged aPTT, normal PT, and the presence of autoantibodies against factor VIII, which are characteristics of AHA. Patients were then treated with corticosteroids to reduce the titer level of autoantibodies and received factor VIII transfusion to stop bleeding. Conclusion. AHA can be suspected in patients presenting with symptoms of bruises without hemarthrosis and without the history of bleeding. Isolated aPTT elevation with normal PT should raise high suspicion of AHA. The presence of FVIII inhibitors can help to confirm the diagnosis of AHA. Treatment consists of factor VIII transfusion and corticosteroid therapy. Bypassing agents are recommended as an alternative to FVIII transfusion.
Investigation of Lade‐Kim Plastic Potential Applicability under Various Stress Paths for Rockfill Materials
Authors: Chen Liping , Bian Shihai , Niu Xiaokai , Zhao Yongbo
Published: September 2021

The dilatancy behavior of rockfill materials shows obvious stress path dependence. Lade‐Kim plastic potential equation has been proposed for a long time to model the mechanical behavior of sand and concrete materials. However, it lacks the verification of rockfill materials, especially under various stress paths. In this paper, the dilatancy performance of coarse‐grained materials under various stress paths is investigated, and then the dilatancy equation description and verification method based on Lade‐Kim plastic potential are given. The applicability of Lade‐Kim plastic potential for different stress path tests, such as conventional triaxial tests, constant P tests, and constant stress (increment) ratio tests, are verified and evaluated. It is found that Lade‐Kim plastic potential is difficult to consider the influence of stress path. Finally, the Lade‐Kim plastic potential, together with nonlinear dilatancy equation, is evaluated by changing the dilatancy equation in the framework of generalized plasticity. Lade‐Kim plastic potential is suitable for constant stress increment ratio loading experiments and special care should be taken when applied to other stress paths. These works are helpful to understand stress path dependence of dilatancy behavior for rockfill materials and is beneficial for the establishment of stress path constitutive model.
Tradeoff of Computation Bits and Computing Speed in an Edge Computing System for Sensor Networks
Authors: Huang Jiaying , Shi Yawen , Wu Fahui
Published: September 2021

Unmanned aerial vehicle (UAV) enabled mobile‐edge computing (MEC) has been recognized as a promising approach for providing enhanced coverage and computation capability to Internet of Things (IoT), especially in the scenario with limited or without infrastructure. In this paper, we consider the UAV assisted partial computation offloading mode MEC system, where ground sensor users are served by a moving UAV equipped with computing server. Computation bits (CB) and computation efficiency (CE) are two vital metrics describe the computation performance of system. To reveal the CB‐CE tradeoff, an optimization problem is formulated to maximize the weighted sum of the above two metrics, by optimizing the UAV trajectory jointly with communication resource, as well as the computation resource. As the formulated problem is non‐convex, it is difficult to be optimally solved in general. To tackle this issue, we decouple it into two sub‐problems: UAV trajectory optimization and resource allocation optimization. We propose an iterative algorithm to solve the two sub‐problems by Dinkelbach’s method, Lagrange duality and successive convex approximation technique. Extensive simulation results demonstrate that our proposed resource allocation optimization scheme can achieve better computational performance than the other schemes. Moreover, the proposed alternative algorithm can converge with a few iterations.
Edge Segmentation Algorithm‐Based Prevention of Recurrent Laryngeal Nerve Injury in Treatment of Thyroid Nodules Using Ultrasound Images
Authors: Wang Jiyuan , Zou Hanqing , Sun Shaokun , Xu Wenqian , Jin Jie
Published: September 2021

The study was aimed to explore the segmentation effects of different algorithms on thyroid nodule ultrasound images, so as to better protect the recurrent laryngeal nerve during thyroid surgery. Specifically, 186 patients with thyroid nodules were selected as the research objects. The segmentation performances of the gradient vector flow (GVF) Snake, Watershed, and Snake algorithms were compared from 6 aspects of image segmentation effects, pixel accuracy (PA), Intersection over Union (IOU) value, algorithm running time, postoperative recurrent laryngeal nerve injury, intraoperative bleeding volume, and postoperative drainage volume. It was found that the average PA value (0.954) and the IOU value (0.866) of the GVF Snake algorithm were obviously higher than those of the other two algorithms. The total incidence of recurrent laryngeal nerve injury based on the GVF Snake algorithm (4.69%) was obviously lower than that of the Snake algorithm (19.35%) and the watershed algorithm (16.13%). The bleeding volume and postoperative drainage volume based on the GVF Snake algorithm were less versus the other two algorithms (

P
<
0.05

). In conclusion, the GVF Snake algorithm demonstrates ideal segmentation effects, which is suggested in the treatment of thyroid nodules to better protect the recurrent laryngeal nerve.
Two New Cases of Primary Microcephaly with Neuronal Migration Defect Caused by Truncating Mutations in the ASPM Gene
Authors: Türkyılmaz Ayberk , Sager Safiye Gunes
Published: September 2021

Autosomal recessive primary microcephaly (MCPH) is a uncommon disorder due to congenital deficiency in the development of the cerebral cortex, characterized by a head circumference below 2 SD. MCPH is a group of diseases with genetic heterogeneity and has been reported by the Online Mendelian Inheritance In Man® (OMIM) database and associated with 25 different genes. It is known that MCPH cases are most frequently associated with abnormal spindle-like, microcephaly-associated (ASPM) gene mutations. The ASPM protein consists of an N-terminal 81 IQ (isoleucine-glutamine) domain, a calponin-homology domain, and a C-terminal domain. It interacts with calmodulin and calmodulin-related proteins via the IQ domain and acts as a part in mitotic spindle function. The basic characteristics of cases with ASPM gene mutations are microcephaly (below −3 SD) present before 1 year of age, intellectual disability, and the absence of other congenital anomalies. Macroscopic organization of the brain is preserved in cases with ASPM mutation, and a decrease in brain volume, particularly gray matter volume loss and a simplified gyral pattern are observed. Cortical migration defects are a very rare finding in patients with ASPM mutations. In the present study, we aimed to discuss the clinical and genetic findings in 2 cases with cortical dysplasia in which truncated variants in the ASPM gene were detected, particularly in terms of genotype-phenotype correlation in comparison with the literature.
Instrumented 5-Time Sit-To-Stand Test: Parameters Predicting Serious Falls beyond the Duration of the Test
Authors: Atrsaei Arash , Paraschiv-Ionescu Anisoara , Krief Helene , Henchoz Yves , Santos-Eggimann Brigitte , Büla Christophe , Aminian Kamiar
Published: September 2021

Background: Falls are a major cause of injuries in older adults. To evaluate the risk of falls in older adults, clinical assessments such as the 5-time sit-to-stand (5xSTS) test can be performed. The development of inertial measurement units (IMUs) has provided the possibility of a more in-depth analysis of the movements’ biomechanical characteristics during this test. The goal of the present study was to investigate whether an instrumented 5xSTS test provides additional information to predict multiple or serious falls compared to the conventional stopwatch-based method. Methods: Data from 458 community-dwelling older adults were analyzed. The participants were equipped with an IMU on the trunk to extract temporal, kinematic, kinetic, and smoothness movement parameters in addition to the total duration of the test by the stopwatch. Results: The total duration of the test obtained by the IMU and the stopwatch was in excellent agreement (Pearson’s correlation coefficient: 0.99), while the total duration obtained by the IMU was systematically 0.52 s longer than the stopwatch. In multivariable analyses that adjusted for potential confounders, fallers had slower vertical velocity, reduced vertical acceleration, lower vertical power, and lower vertical jerk than nonfallers. In contrast, the total duration of the test measured by either the IMU or the stopwatch did not differ between the 2 groups. Conclusions: An instrumented 5xSTS test provides additional information that better discriminates among older adults those at risk of multiple or serious falls than the conventional stopwatch-based assessment.
Group Composition and Social Structure of Red-Shanked Doucs (Pygathrix nemaeus) at Son Tra Nature Reserve, Vietnam
Authors: Ulibarri Lawrence R. , Gartland Kylen N.
Published: September 2021

Multilevel societies, consisting of multiple one-male multi-female units, are relatively rare among primates, but are more widespread in the odd-nosed colobines than other taxa. Multilevel societies are found particularly in snub-nosed monkeys (Rhinopithecus)and have been debated in studies of proboscis monkeys (Proboscis). While it has been suggested that douc langurs (Pygathrix) may also form multilevel societies, the limited data available make the details of their social organization unclear. We aimed to establish a more comprehensive picture of the social organization of red-shanked doucs (Pygathrix nemaeus) and to address the question of whether this species forms multilevel societies, specifically collections of multiple distinct one-male units hereafter termed “bands.” We collected 259 h of behavioral data at Son Tra Nature Reserve in Vietnam from February 2010 to May 2011. The mean band size was approximately 18 individuals. Bands were comprised of approximately 2.7 units, and each unit contained approximately 6.5 individuals. Units had an average sex ratio of 1.0:1.6. We observed fission and fusion behaviors which were not correlated with phenological or weather measures. Activity budget data showed that fission and fusion behaviors between units were positively correlated with activity. Both vocalizations and vigilance increased when units engaged in fission. Based on this evidence, P. nemaeus at Son Tra Nature Reserve appear to engage in daily fission-fusion activity which does not vary between seasons. Additionally, our data suggest that these primates may form multilevel societies made up of distinct units. However, future data including proximity pattern analyses are necessary for confirmation.
Fuzzy membership functions tuning for speed controller of induction motor drive: performance improvement
Authors: Farah Nabil , Talib Md Hairul Nizam , Ibrahim Zulkifilie Bin , Abdullah Qazwan , Aydoğdu Ömer , Lazi Jurifa Mat , Isa Zm
Published: September 2021

Fuzzy logic controller (FLC) has gained high interest in the field of speed control of machine drives in both academic and industrial communities. This is due to the features of FLC of handling non-linearity and variations. FLC system consists of three main elements: scaling factors (SFs), membership functions (MFs), and rule-base. Fuzzy MFs can be designed with different types and sizes. For induction motor (IM) speed control, (3x3), (5x5) and (7x7) MFs are the most used MFs sizes, and normally designed based on symmetrical distribution. However, changing the width and peak position of MFs design enhance the performance. In this paper, tuning of MFs of FLC speed control of IM drives is considered. Considering (3x3), (5x5) and (7x7) MFs sizes, the widths and peak positions of these MFs are asymmetrically distributed to improve the performance of IM drive. Based on these MFs sizes, the widths and peak positions are moved toward the origin (zero), negative and positive side that produces a controller less sensitive to the small error variations. Based on simulation and performance evaluations, improvement of 5% in settling time (Ts), 0.5% in rise time and 20% of steady-state improvement achieved with the tuned MFs compared to original MFs.
Impact of distributed power generation on protection coordination in distribution network
Authors: Idrissi Zineb El , El Mariami Faissal , Belfqih Abdelaziz , Haidi Touria
Published: September 2021

In the whole world and especially in Morocco, the electric power sector faces significant challenges and the demand for energy is increasing as fossil fuel sources are disappearing. Moreover, the high cost of construction of large production plants and the obligation to reduce greenhouse gas emissions are among the factors pushing the energy sector to integrate distributed generators DGs based on renewable energies into power grids. However, the integration of these generators increased the values of short-circuit currents in the network, which poses a real threat to the existing protection coordination systems in the distribution network. The aim of this article is to bring together in a single platform all available research addressing the issue of protection coordination in the presence of DGs in the distribution network, in order to help researchers identify future scope. This paper presents a review of the impact of distributed generators on the protection coordination of distribution networks. The solutions proposed in the literature, to mitigate the negative impact of DGs, have been investigated in detail, along with the limitations of these proposed techniques.
Load shedding scheme based metaheuristic technique for power system controlled islanding
Authors: Saharuddin N. Z. , Abidin I. Zainal , Mokhlis H. , Shair E. F.
Published: September 2021

Power system-controlled islanding is one of the mitigation techniques taken to prevent blackouts during severe outage. The implementation of controlled islanding will lead to the formation of few islands, that can operate as a stand-alone island. However, some of these islands may not be balanced in terms of generation and load after the islanding execution. Therefore, a good load shedding scheme is required to meet the power balance criterion so that it can operate as a balanced stand-alone island. Thus, this paper developed a load shedding scheme-based metaheuristics technique namely modified discrete evolutionary programming (MDEP) technique to determine the optimal amount of load to be shed in order to produce balanced stand-alone islands. The developed load shedding scheme is evaluated and validated with two other load shedding techniques which are conventional EP and exhaustive search techniques. The IEEE 30-bus and 39-bus test systems were utilized for this purpose. The results proves that the load shedding based MDEP technique produces the optimal amount of loads to be shed with shortest computational time as compared with the conventional EP and exhaustive search techniques.
Distribution of attempted leader with monsoon seasons and negative cloud-to-ground flashes in Melaka, Malaysia
Authors: Isa Nur Asyiqin , Baharudin Zikri Abadi , Zainuddin Hidayat , Sutikno Tole , Zainon Maslan , Zulkefle Ahmad Aizan
Published: September 2021

Ninety (90) waveforms recognized as attempted leader were identified with both positive (84 events) and negative (6 events) initial polarity observed from four consecutive years of data (N=10,206). The positive attempted leader shows no correlation with the number of thunderstorms producing it during monsoon. Meanwhile, the negative attempted leader during monsoon and both polarity of attempted leader (positive and negative) during inter-monsoon shows positive correlation with the number of thunderstorms producing it. In this study, the yearly statistical distribution of negative cloud-to-ground (CG) lightning flashes which were classified as positive preliminary breakdown pulses (214 events) and negative preliminary breakdown pulses (4982 events) in accordance of their preliminary polarity were also presented. In addition, there is no relationship of attempted leader and the initial breakdown of negative ground flash since both mechanisms performed as a negative correlation.
Multilinear principal component analysis for iris biometric system
Authors: Kamlaskar Chetana , Abhyankar Aditya
Published: September 2021

Iris biometric modality possesses inherent characteristics which make the iris recognition system highly reliable and noninvasive. Nowadays, research in this area is challenging compact template size and fast verification algorithms. Special efforts have been employed to minimize the size of the extracted features without degrading the performance of the iris recognition system. In response, we propose an improved feature fusion approach based on multilinear subspace learning to analyze Iris recognition. This approach consists of four stages. In the first stage, the eye image is segmented to extract the iris region. In the second step, wavelet packet decomposition is conducted to extract features of the iris image, since good time and frequency resolutions can be provided simultaneously by the wavelet packet decomposition. In the next step, all decomposed nodes or packets are arranged as a 3rd order tensor rather than a long vector, in which feature fusion is directly implemented with multilinear principal component analysis (MPCA). This approach provides a more compact or useful low-dimensional representation directly from the original tensorial representation. Finally, a discriminative tensor feature selection mechanism and classification strategy are applied to iris recognition problem. The obtained results indicate the usefulness of MPCA to select discriminative features and fuse them effectively. The experimental results reveal that the proposed tensor-based MPCA approach achieved a competitive matching performance on the SDUMLA-HMT Iris database with an adequate acceptable rate.
Different soliton pulse order effects on the fiber communication systems performance evaluation
Authors: A. Eid Mahmoud M. , A. Mohammed Abd El-Naser , Zaki Rashed Ahmed Nabih
Published: September 2021

The study outlined the soliton pulse order effects on the performance efficiency of the optical transceiver systems. The power after fiber is reported for various Soliton pulse order. Max optical signal power (SP) and min optical noise power (NP) are clarified versus time after optical fiber for various soliton pulse order. As well as the max electrical power amplitude against time period is demonstrated after electrical filter for various soliton pulse order. It is reported that the optical transceiver performance efficiency can be upgraded with the first soliton order pulse. The soliton technique is used for high speed communication transmission systems. Soliton technique is used to compensate the dispersion and balanced with nonlinear effects. The soliton order effects is then discussed to choose the suitable soliton order for high speed system performance efficiency. The soliton techniques can be used also for extended ultra high transmion distance with high data rates.
The rogue access point identification: a model and classification review
Authors: Arisandi Diki , Ahmad Nazrul Muhaimin , Kannan Subarmaniam
Published: September 2021

Most people around the world make use of public Wi-Fi hotspots, as their daily routine companion in communication. The access points (APs) of public Wi-Fi are easily deployed by anyone and everywhere, to provide hassle-free Internet connectivity. The availability of Wi-Fi increases the danger of adversaries, taking advantages of sniffing the sensitive data. One of the most serious security issues encountered by Wi-Fi users, is the presence of rogue access points (RAP). Several studies have been published regarding how to identify the RAP. Using systematic literature review, this research aims to explore the various methods on how to distinguish the AP, as a rogue or legitimate, based on the hardware and software approach model. In conclusion, all the classifications were summarized, and produced an alternative solution using beacon frame manipulation technique. Therefore, further research is needed to identify the RAP.
Mathematical modeling and algorithm for calculation of thermocatalytic process of producing nanomaterial
Authors: Ismailov Bakhtiyar , Umarova Zhanat , Ismailov Khairulla , Dosmakanbetova Aibarsha , Meldebekova Saule
Published: September 2021

At present, when constructing a mathematical description of the pyrolysis reactor, partial differential equations for the components of the gas phase and the catalyst phase are used. In the well-known works on modeling pyrolysis, the obtained models are applicable only for a narrow range of changes in the process parameters, the geometric dimensions are considered constant. The article poses the task of creating a complex mathematical model with additional terms, taking into account nonlinear effects, where the geometric dimensions of the apparatus and operating characteristics vary over a wide range. An analytical method has been developed for the implementation of a mathematical model of catalytic pyrolysis of methane for the production of nanomaterials in a continuous mode. The differential equation for gaseous components with initial and boundary conditions of the third type is reduced to a dimensionless form with a small value of the peclet criterion with a form factor. It is shown that the laplace transform method is mainly suitable for this case, which is applicable both for differential equations for solid-phase components and calculation in a periodic mode. The adequacy of the model results with the known experimental data is checked.
Efficient hardware implementation for lightweight mCrypton algorithm using FPGA
Authors: Abbas Yasir Amer , Hameed Ahmed Salah , Alwan Safa Hazim , Fadel Maryam Adnan
Published: September 2021

The lightweight cryptography is used for low available resources devices such as radio frequency identification (RFID) tags, internet of things (IoTs) and wireless sensor networks. In such case, the lightweight cryptographic algorithms should consider power consumption, design area, speed, and throughput. This paper presents a new architecture of mCrypton lightweight cryptographic algorithm which considers the above-mentioned conditions. Resource-shared structure is used to reduce the area of the new architecture. The proposed architecture is implemented using ISE Xilinx V14,5 and Spartan 3 FPGA platform. The simulation results introduced that the proposed design area is 375 of slices, up to 302 MHz operating frequency, a throughput of 646 Mbps, efficiency of 1.7 Mbps/slice and 0.089 Watt power consumption. Thus, the proposed architecture outperforms similar architectures in terms of area, speed, efficiency and throughput.
Assessment of online education problems during the COVID-19 pandemic in Russia
Authors: Garafiev Ilshat , Garafieva Gulshat , Idiatullina Angelika , Spirchagova Elena
Published: September 2021

The work studied the assessment of online education problems during the COVID-19 pandemic by the first year master’s students. It was hypothesized that there are two types of problems. The first type is the problems associated with the difficulties of online communication between the participants of the educational process. The second type is the problems associated with the technical difficulties of participating in online education. The results of factor analysis show that masters clearly distinguish between the content-related (online communication) and formal (technical problems) sides of the organization of online education. It was found that those masters’ students who do not work now or do not have work experience in the specialty for which they are studying generally perceive the presence of technical problems and Internet disruptions as difficulties in implementing online education more significantly.
Alternative liquid dielectrics in power transformer insulation: a review
Authors: Tlhabologo Bokang Agripa , Samikannu Ravi , Mosalaosi Modisa
Published: September 2021

Transformer liquid dielectrics evolved where mineral oil has been the dominant choice until emergence of synthetic esters and natural esters. Natural ester-based oils have been under extensive investigations to enhance their properties for replacing petroleum-based mineral oil, which is non-biodegradable and has poor dielectric properties. This paper focuses on exposition of natural ester oil application in mixed transformer liquid dielectrics. Physical, chemical, electrical, and ageing characteristics of these dielectrics and the dissolved gas analysis (DGA) were reviewed. Physical properties include viscosity, pour point, flash and fire point which are vital indicators of heat insulation and fire risk. Chemical properties considered are water content, acid number, DGA, corrosive sulphur, and sludge content to limit and detect degradation and corrosion due to oil ageing. Electrical properties including breakdown voltage were considered for consistent insulation during overload and fault conditions. These properties of evolving alternative dielectrics were reviewed based on ASTM International standards and International Electro technical Commission standards for acceptable transformer liquid dielectrics. This review paper was compiled to avail modern methodologies for both the industry and scholars, also providing the significance of using mixed dielectrics for power transformers as they are concluded to show superiority over non-mixed dielectrics.
Enhanced Flip-FBMC visible light communication model
Authors: Qasim Abdullah Ali , Mohammedali Husam Noman , Abdullah M. F. L. , Talib R. , Dhaam Haidar Zaeer
Published: September 2021

VLC technology is one of the most promising technologies in the generations of communications, especially 5G after the significant development of optical semiconductors, specific laser diode, and the use of FBMC modulation in the system. DCO-FBMC modulation surpasses all the disadvantages of DCO-OFDM modulation techniques, as it is characterized by high speed and large bandwidth, but this technique consumes high energy when converting a real bipolar signal into a positive unipolar by adding DC-bias. Besides the challenge of illumination distribution indoor typical room, where the drop of the illumination appears in the middle of the room, besides the power consumption. The Flip-FBMC technique was proposed to solve this challenge, which helps convert the bipolar signal into unipolar by separating the positive part from the negative part and converting it into positive and merging it using Multiplexer and then sending the signal. Besides this, the authors presented in this paper a new lighting model with 5 luminescent units, using LD instead of LED. The Flip-FBMC profile gave better energy savings and BER performance than DCO-FBMC, besides a lighting model that covers dark areas and gives high SNR for the blind area and give save power 13.14% from consumed power.
GWO-based MPPT controller for grid connected Solid oxide fuel cell with high step up DC-DC converter
Authors: Ponnuru Sudhakiran , Kumar R. Ashok , Jothi Swaroopan N. M.
Published: September 2021

The solid oxide fuel cell (SOFC) is used as secondary source in micro grid application. When the renewable sources are not able meet the load requirement, Battery energy back-up system is supposed to supply the energy to meet the demand. The SOFC come into action when the state of charge (SOC) of battery energy backup becomes too low. The SOFC parameters are assumed as constant during its operation but those operating parameters are not practically constant. The operating parameters vary widely which will influence the output voltage of SOFC. Hence an optimum power extracting controller is being implemented to ensure maximum power under dynamic operating condition. A high step up converter is designed to boost the output voltage of SOFC whose steady state analysis is studied in this work. The switches of high step up converter are triggered using optimum power controller using grey wolf based optimization algorithm. The proposed controller performance is compared with conventional particle swarm optimization based controller. The simulation is carried out using MATLAB/simulink and results discussed.
A novel hybrid approach based artificial bee colony and salp swarm algorithms for solving ORPD problem
Authors: Salhi Souheil , Naimi Djemai , Salhi Ahmed , Abujarad Saleh , Necira Abdelouahab
Published: September 2021

Optimal reactive power dispatch (ORPD) is an important task for achieving more economical, secure and stable state of the electrical power system. It is expressed as a complex optimization problem where many meta-heuristic techniques have been proposed to overcome various complexities in solving ORPD problem. A meta-heuristic search mechanism is characterized by exploration and exploitation of the search space. The balance between these two characteristics is a challenging problem to attain the best solution quality. The artificial bee colony (ABC) algorithm as a reputed meta-heuristic has proved its goodness at exploration and weakness at exploitation where the enhancement of the basic ABC version becomes necessary. Salp swarm algorithm (SSA) is a newly developed swarm-based meta-heuristic, which has the best local search capability by using the best global solution in each iteration to discover promising solutions. In this paper, a novel hybrid approach-based ABC and SSA algorithms (ABC-SSA) is that developed to enhance the exploitation capability of the ABC algorithm using SSA and applied for solving ORPD problem. The efficiency of ABC-SSA is investigated using two standard test systems IEEE-30 and IEEE-300 buses, and that by considering the famous objective functions in ORPD problem.
Identification of optimum segment in single channel EEG biometric system
Authors: Hendrawan Muhammad Afif , Saputra Pramana Yoga , Rahmad Cahya
Published: September 2021

Nowadays, biometric modalities have gained popularity in security systems. Nevertheless, the conventional commercial-grade biometric system addresses some issues. The biggest problem is that they can be imposed by artificial biometrics. The electroencephalogram (EEG) is a possible solution. It is nearly impossible to replicate because it is dependent on human mental activity. Several studies have already demonstrated a high level of accuracy. However, it requires a large number of sensors and time to collect the signal. This study proposed a biometric system using single-channel EEG recorded during resting eyes open (EO) conditions. A total of 45 EEG signals from 9 subjects were collected. The EEG signal was segmented into 5 second lengths. The alpha band was used in this study. Discrete wavelet transform (DWT) with Daubechies type 4 (db4) was employed to extract the alpha band. Power spectral density (PSD) was extracted from each segment as the main feature. Linear discriminant analysis (LDA) and support vector machine (SVM) were used to classify the EEG signal. The proposed method achieved 86% accuracy using LDA only from the third segment. Therefore, this study showed that it is possible to utilize single-channel EEG during a resting EO state in a biometric system.
Educação Remota em Tempos de Pandemia: reflexões no contexto acadêmico
Authors: Bollela Valdes Roberto , Medeiros Lgor Studart , Telles Simone
Published: September 2021

A pandemia da Covid-19 e as ações para seu enfrentamento resultaram, entre outras coisas, na suspensão das aulas presenciais nas instituições de ensino e em todos os níveis, da educação básica ao ensino superior. Seguindo as recomendações do Ministério da Saúde e da Secretaria Estadual da Saúde e sem poder manter as atividades de ensino presenciais, estudantes, professores e especialistas da área tiveram a oportunidade de vivenciar uma nova realidade educacional que teve a tecnologia e recursos de educação a distância (EaD) como as principais ferramentas disponíveis para manutenção do processo de ensino e aprendizagem ao longo do ano de 2020. Este artigo tem como objetivo compartilhar reflexões sobre ações e estratégias utilizadas no ensino superior, focando as potencialidades EaD e da educação remota em sua modalidade emergencial (ERE). A partir do impacto resultante da pandemia, apresentaremos neste artigo alguns princípios e aspectos relevantes e necessários aos processos de ensino, aprendizagem e avaliação de estudantes. As discussões não recaíram sobre o uso da tecnologia e possíveis recursos que podem ser utilizados em sala de aula, mas sim sobre as possibilidades de transformação dos programas educacionais com base nos princípios que regem as boas práticas, seja no ensino presencial, a distância ou híbrido. Destacam-se, neste artigo, discussões a respeito dos princípios básicos na organização da atividade educacional; desenvolvimento docente e mérito acadêmico a partir de treinamento docente para o uso de novas estratégias e tecnologias de ensino e avaliação; infraestrutura, recursos humanos e acessibilidade para EaD ressaltando a importância da disponibilização de recursos e infraestrutura básica de TI para apoiar atividades mediadas por tecnologia. Também abordamos os Ambientes Virtuais de Aprendizagem (AVA) como espaços que permitem oferecimento de conteúdo e gestão da aprendizagem; avaliação dos estudantes; revisão da política institucional, normas e regras da EaD enquanto mecanismos que podem zelar pela organização pedagógica e curricular dos cursos ofertados.
Extensão universitária na interface virtual: estratégias de aprimoramento docente e discente do curso de fisioterapia da Universidade Federal de Minas Gerais (UFMG)
Authors: Ferreira Fabiane Ribeiro , Ferreira Érica de Matos Reis , Vaz Daniela Virgínia
Published: September 2021

A pandemia causada pelo COVID-19, em 2020, resultou no esvaziamento das salas de aula como estratégia de distanciamento para a controle da disseminação do vírus. As universidades, através de seus gestores e docentes, buscaram maneiras de viabilizar a continuidade das atividades acadêmicas pautando-se na cooperação, solidariedade e inovação. Foi imprescindível buscar aprimoramentos para desenvolver o processo de aprendizagem no formato de Ensino Remoto Emergencial (ERE). Neste cenário, a extensão universitária cumpriu um importante papel. Este trabalho relata o processo de criação dos projetos Aprimoramento Docente para Ensino Superior da Fisioterapia (ADES-FIT) eAprimoramento Discente para o Ensino Superior (ADES Jr.), seus objetivos e atividades realizadas. Acredita-se que iniciativas pautadas na colaboração e com o envolvimento ativo para o aprendizado possam ressignificar as experiências no contexto da universidade.