bluuebunny/crossref_metadata_2025 huggingface dataset:
Sporcuların ve E-spor Oyuncularının Dijital Oyun Bağımlılığı ve Dijital Oyun Bağımlılığına İlişkin Farkındalık Düzeyleri
Authors: CAN Hasan Ceyhun , TEKKURŞUN DEMİR Gönül
Published: October 2020

Günümüzde dijitalleşmenin yaygınlaşması sonucu dijital oyun bağımlılığı sorunu baş göstermiştir. Bu bağlamda araştırmada sporcuların ve e-spor oyuncularının dijital oyun bağımlılığı ve dijital oyun bağımlılığına ilişkin farkındalık düzeyinin incelenmesini amaçlamıştır. Araştırmada tarama modelinden ilişkisel tarama modeli kullanılmıştır. Araştırmaya günde en az 30 dakika bir e-spor oyununu oynayan ve haftada en az 2 gün spor yapan 61 sporcu, 80 e-spor oyuncusu katılmıştır. Veri toplama aracı olarak, Akın, Usta, Başa ve Özçelik’in (2016) Türkçeye uyarladığı Oyun Bağımlılığı Ölçeği (OBÖ) ile Demir ve Cicioğlu’nun (2020) geliştirdiği Dijital Oyun Bağımlılığına İlişkin Farkındalık Ölçeği (DOBİFÖ) kullanılmıştır. Verilerin analizinde Pearson Spearman Korelasyon, Mann-Whitney U Testi, Kruskal-Wallis Testinden yararlanılmıştır. OBÖ ve DÖBİFÖ puanları arasında negatif yönde yüksek düzeyde anlamlı ilişki saptanmıştır. Dijital oyun bağımlılığı puanının erkek e-spor oyuncularının lehine anlamlı farklılık gösterdiği saptanmıştır. Sporcuların yaşı ile OBÖ arasında pozitif yönde orta düzeyde, DÖBİFÖ puanı arasında negatif yönde orta düzeyde anlamlı ilişki bulunmuştur. Zararlı alışkanlığa sahip olma durumuna göre OBÖ ve DOBİFÖ arasında anlamlı farklılık saptanmamıştır. Katılımcıların günlük dijital oyun oynama süresi ile OBÖ ve DOBİFÖ puanları arasında anlamlı farklılık tespit edilmiştir. Araştırma sonucunda, e-spor oyuncularının sporculara göre yüksek düzeyde oyun bağımlılığına sahip olduğu ve oyun bağımlılığına ilişkin farkındalıklarının sporculardan daha yüksek olduğu tespit edilmiştir.
South Asian Print Media and Children Rights Discourse: A Critical Analysis of Pakistan – India Press
Authors: Mengal Taj , Mahmood Tahir , Faiz Rukhsana
Published: October 2020

Children rights are highlighted by various authors, columnist and media persons from time to time. The purpose of this study is to identify the imperative issues of children in South Asia especially Pakistan and India. This research article aims to provide information to the advisers and policy makers to shift particular difficulties of children rights to the forefront of public conscience. For this purpose, two dailies, The Nation from Pakistan and The Hindu from India were selected to find out the value given to children rights. The study shows that the coverage of children rights of education, health, safety and development rights were hardly covered in Pakistan and India print media and it is rarely prominent to identify the important issues related to children rights. This survey also examines that there are significant difference in the coverage of India and Pakistan newspapers which reports to the children issues.
AfricArXiv – the pan-African Open Scholarly Repository(dissemination document)
Authors: Okelo Luke , Havemann Johanna , Ahinon Justin , Ahmad Umar , Aldirdiri Osman
Published: October 2020

AfricArXiv is a community-led digital archive for African research working towards building an Africa-owned open scholarly repository; a knowledge commons of African scholarly works. We are partnering with established scholarly repository services to provide a platform for African scientists of any discipline to present their research findings and connect with other researchers – on the African continent and globally. It is our aim to promote discoverability of African research output according to sfDORA : https://sfdora.org/read/ FAIR principles: https://www.go-fair.org/fair-principles/ Helsinki Initiative on Multilingualism: https://www.helsinki-initiative.org/en To contextualize the above to the African scholarly community we have postulated 10 African Principles for Open Access in Scholarly Communication: https://info.africarxiv.org/african-oa-principles/
Factors causing design changes in Vietnamese residential construction projects: An evaluation and comparison
Authors: Khanh Ha Duy
Published: October 2020

Most of the construction projects in Vietnam are suffering from the design changes during the implementation phase. These changes have a significant impact on the time and cost of the project. The primary purpose of this study is to explore factors causing the design change of residential construction projects from the Vietnamese perspective. This study has used a questionnaire to collect data for the occurrence and effect of these factors on project performance. Based on the literature review, there are a total of 28 initial factors filtered. These factors were classified into four cases: environment, clients, consultants, and contractors. The results of the analysis showed that there is almost no difference in mean between groups of respondents, and there is a relatively high consensus in ranking the factors between project parties. Based on factor analysis, there are four principal components extracted from all initial factors, with total variance explained of nearly 65.2%. In addition, an evaluation sheet for the overall impact of factors on project performance is proposed. The result indicated that the level of impact is 70.7 per the scale of 100. Eventually, a comparison with other construction project types has been made to understand generally the factors of design changes in the construction industry.

Keywords:

design change; residential building; construction management; Vietnam.
A hybrid model for predicting missile impact damages based on k-nearest neighbors and Bayesian optimization
Authors: Doan Quoc Hoan , Thai Duc-Kien , Tran Ngoc Long
Published: October 2020

Due to the increase of missile performance, the safety design requirements of military and industrial reinforced concrete (RC) structures (i.e., bunkers, nuclear power plants, etc.) also increase. Estimating damage levels in the design stage becomes a crucial task and requires more accuracy. Thus, this study proposed a hybrid machine learning model which is based on k-nearest neighbors (KNN) and Bayesian optimization (BO), named as BO-KNN, for predicting the local damages of reinforced concrete (RC) panels under missile impact loading. In the proposed BO-KNN, the hyperparameters of the KNN were optimized by using the BO which is a well-established optimization algorithm. Accordingly, the KNN was trained on an experimental dataset that consists of 254 impact tests to predict four levels (or classes) of damages including perforation, scabbing, penetration, and no damage. Due to the unbalance of the number of tests in each damage class, an over-sampling technique called BorderlineSMOTE was employed as a balancing solution. The predictability of the proposed model was investigated by comparing with the benchmark models including non-optimized KNN, multilayer perceptron (MLP), and decision tree (DT). Accuracy, F1-score, and area under the receiver operating characteristic (ROC) curve (AUC) were utilized to evaluate the performance of these models. The implementation results showed that the proposed BO-KNN model outperformed the other benchmark models with the average class accuracy of 68.05%, F1-score = 0.641, and AUC = 85.8%. Thus, the proposed model can be introduced as a foundation for developing a tool for predicting the local damage of RC panels under the missile impact in the future.

Keywords:

impact damage; k-nearest neighbors; Bayesian optimization; oversampling; imbalanced data; RC panel.
Development of a cementless eco-binder as an alternative to traditional Portland cement in construction activities
Authors: Phuoc Huynh Trong , Hung Vu Viet , Tuan Bui Le Anh , Giang Pham Huu Ha
Published: October 2020

In this research, the performance of a cementless eco-binder, a mixture of waste materials including slag, circulating fluidized bed combustion ash (CFA), and rice husk ash (RHA) was investigated, in which CFA acted as an activator. One hundred and twenty paste samples were prepared by using the RHA/(slag + RHA) ratios of 0, 15, 30, 45% while keeping a constant ratio of CFA/(slag + RHA) at 25%. The setting period, compressive strength, the ultrasonic pulse velocity (UPV), and drying shrinkage of paste samples were determined at the samples’ age of up to 91 days. In addition, the microstructures of all paste samples were also characterized by scanning electron microscopy (SEM). It was found that the use of cementless eco-binder significantly increased the setting times, lower compressive strength, drying shrinkage, and UPV values compared to the control OPC sample. The maximum 91-day-old compressive strength gained by the binary binder of slag and CFA (R00C25) was 90% of that of the control specimen. Incorporation of RHA with higher replacement levels up to 45% resulted in a significant decrease in compressive strength up to 50%. Moreover, the SEM analysis revealed that there was a large difference in the microstructures of the control and the cementless eco-binder samples, in which the main hydration products were C-S-H/C-A-S-H gels and ettringite (AFt) due to relatively high amount of SO3 and SiO2 in the CFA and RHA, respectively. Thus, it can be realized that the potential for the use of slag, CFA, and RHA as a sustainable cement-free binder is promising in the construction industry, especially for lower strength or no required early high strength structures.

Keywords:

cementless eco-binder; circulating fluidized bed combustion; rice husk ash; slag; microstructure; compressive strength; drying shrinkage; setting time; ultrasonic pulse velocity.
Identity as a Lens on Livelihoods: Insights From Turkana, Kenya
Authors: Rodgers Cory
Published: October 2020

Livelihood surveys often categorise pastoralist households by economic activity and material assets, using measures such as herd ownership, extent of mobility and the degree of reliance on livestock vs other sources of subsistence and income. However, in contexts of high variability and uncertainty, such objective classifications may inadvertently perpetrate two distortions. First, they stabilise highly fluid economic landscapes, overlooking the ways in which people draw opportunistically from an array of livelihood strategies or move between them over time. Second, they may flatten the social field, overlooking the ways that class and kinship structure and constrain people’s livelihood options. This paper argues for greater attention to subjective assessments of livelihood, such as the labels by which people self-identify or distinguish themselves from others. Drawing on over twenty months of anthropological fieldwork, I describe the notion of raiya, a polysemous identity construct that has become a salient part of everyday discourse in Turkana County, Kenya. While raiya connotes an array of conventional dichotomies – including rural/urban, traditional/modern and nomadic/sedentary – attention to the uses of this term in ‘speech acts’ reveals how it is used to manage relationships and access opportunities across these apparent divisions. This example demonstrates how research on identity practices can inform the study of livelihoods, not only because self-identification indicates a commitment to certain cultural values (Moritz 2012), but also because identity labels highlight the messy processes of boundary-shifting and boundary-crossing that characterise social and economic life under conditions of high variability.
Socio-Technical Objects at the Crossroads Between 'Universal' Policy Models for Livestock Production Development, Local Practices and Dynamics of Change
Authors: Magnani Sergio
Published: October 2020

Relationships between public policy, resource management and the larger economic contexts remain poorly understood in the African drylands. A better understanding of changes in pastoral systems requires shifting the focus from a static and linear analysis to a dynamic one encompassing processes, relationships and contexts.

A three-year fieldwork research experience on three different case studies in Senegal has led to the identification of three material objects at the interface between pastoral systems and development interventions: cattle breeds, feeding and milk. Such objects are at the heart of pastoral systems, and are typically crucial to policymakers’ attempts to intensify pastoral production.

By raising the example of cattle feeding in Northern Senegal, I suggest that a methodological and analytical framework focusing on the socio-political dimensions of technical objects can be useful to analyse the encounter between the linear and universal input/output rationality of livestock development models and those of pastoralists, based on the embeddedness of socio-political, economic and environmental variability.

Such an approach, I thus argue, can be used to deconstruct production models, highlighting the context of production and the modes of operation of the social actors. This could open up a space to describe social and technical change beyond abstract and ‘universal’ development models, and to promote more inclusive and empirically based policy-making.
Effectiveness of the ViSC Social Competence Program in Turkish Elementary Schools
Authors: Doğan Aysun , Strohmeier Dagmar , Kızıltepe Rukiye , Gümüşten Durdane , Yanagida Takuya
Published: October 2020

This study examined whether participating in the ViSC social competence program is able to reduce different types of reported problem behaviors including bullying perpetration and victimization as well as promoting various social competencies in elementary school children. Two wave longitudinal self-report and teacher report data was available from 822 students (546 intervention group, 276 control group, 50% girls, Mage = 9.30) from five intervention (23 classes) and four control (14 classes) schools. Multilevel growth models revealed a more favorable development of the ViSC intervention group compared with the control group in three student-reported and all teacher reported variables. Participating in the program reduced conduct problems, reactive and proactive aggression and promoted school bonding, relationships with classmates, emotional regulation, and prosocial skills. However, the program was not effective regarding the reduction of bullying and victimization. Findings are discussed with regard to the implementation of future bullying prevention programs and social policies in Turkish schools.
Research on data mining equipment for teaching English writing based on application
Authors: Li Bo , Su Zheqian
Published: October 2020

“College English teaching guide” puts in forth unique challenges and needs for College teaching skills of English. It is pressing to cultivate innovative talents with quality writing in English. Teaching in English, as a subject to check the mastery of students’ English knowledge. The successful instructional project of English writing is an assurance and support smooth growth of English writing. It can make education get double the efforts, and allow the students development.’ writing ability y, but in fact, the current situation of structural design of writing English in college is not optimistic. With the rise of “Web in addition to”, varying backgrounds have experienced emotional changes. “Web in addition to training” has become a pattern of advancement, which has brought new chances and difficulties for the educating and learning of College English composition. This research first describes the research status of data mining and College English writing at places of abroad and input the future the content of research and methods of research. Taking college English writing teaching as the research object, the association rules algorithm in data mining is applied to analyze the correlation factors of students’ writing performance and provide decision-making suggestions for teachers’ teaching.
An LDA based model for semantic annotation of Web English educational resources
Authors: Fei Xue
Published: October 2020

With the development and application of Web Semantic, users are no longer satisfied with basic metadata descriptions such as titles and link texts and string-matching search results. They hope that the resource description can provide the theme ideas, topics, and topics involved in the resource. Potential semantic information contains documents such as teaching methods and knowledge-concept relationships. This research starts from the demand for semantic annotation of resources in the process of resource library construction and sharing, and uses the LDA model to semantically model the document resources in the resource library to mine potential topics in the document. From “document-topic-keyword” scheme, the semantic description of teaching resources at different levels enriches the metadata attributes and content of resources, and adds more related topics and corresponding keyword descriptions related to disciplines, teaching content, teaching methods, etc., providing resource retrieval and sharing. The experimental results show that the LDA model can catalogues teaching resources from a macro perspective, and model LDA on teaching subject resources of the same teaching content. It can mine the inherent semantic topic features and detailed differences of resources. The final performance analysis verifies LDA’s advantages of the model in parallel computing in the big data environment.
An artificial intelligence recognition model for English online teaching
Authors: Aiyuan Li , Hui Wang
Published: October 2020

The traditional English online teaching model is limited by the teaching location and the difficulty of online teaching, which prevents teachers from controlling students. In order to improve the ability of the English online teaching model to supervise and recognize the status of students, this paper proposes an English online teaching model based on artificial intelligence technology, and adopts a positioning method based on an improved deep belief network for real-time position control and status recognition for students in online learning. Moreover, this study combines intelligent algorithms to build the model structure and verify the performance of the model. The results show that the performance of the model is good. In addition, on the basis of performance testing, the recognition effect of the artificial intelligence-based student online learning recognition model constructed in this paper is recognized. The results show that the model proposed in this paper has a certain effect and meets the actual needs of intelligent teaching.
Ideological and political teaching model using fuzzy analytic hierarchy process based on machine learning and artificial intelligence
Authors: Wang Yuxia
Published: October 2020

Ideological and political education plays an important role in supporting social talent input. However, the current evaluation effect of ideological and political education is difficult to quantify. Therefore, in order to improve the evaluation effect of ideological and political education, based on artificial intelligence algorithms, this study combines machine learning ideas and the current status of ideological and political education to build a fuzzy analytic hierarchy process model of the of ideological and political teaching quality based on machine learning and artificial intelligence. Moreover, this study uses a three-tier structure to build a model network structure, and based on the characteristics of fuzzy evaluation, this study uses the expert system to conduct data management, operation and control of model evaluation, and build a corresponding database to update the data in real time. In addition, in order to verify the effect of the model, this study sets simulation experiments to analyze the model performance. From the point of view of running effect and running speed, this research model meets the actual needs of the system, so it can be applied to the evaluation process of ideological and political teaching quality in colleges and universities.
Reform of English interactive teaching mode based on cloud computing artificial intelligence – a practice analysis
Authors: Liang Xiufang , Haiping Lv , Liu Jie , Lin Lin
Published: October 2020

Based on the cloud computing artificial intelligence model, the English interactive teaching model summarized and analyzed in an in-depth manner, the characteristics of the smart classroom explored, and the interactive teaching model reform practiced. This article has studied and analyzed the classic teaching model. Finally, based on constructivism, the advantages of the constructivism teaching model, cooperative teaching model, and mastering learning model selected to construct the teaching model of artificial intelligence courses. Through the questionnaire survey of the current teaching status of artificial intelligence courses, and the investigation of each link of the constructed model, according to the results of the survey to optimize the construction of artificial intelligence courses teaching model to make it more perfect. Based on the cloud computing technology, the system architecture and function module division of the network open class platform designed based on the overall needs, and developed and implemented on this basis. Through global and local two-level authentication, user information synchronization, and interconnection between homogeneous clouds, the identity management function realized. With the help of the e-schoolbag function, the learning results continuously and accurately evaluated, so that every learner can get a good learning experience.
Performance analysis of public management teaching practice training based on artificial intelligence technology
Authors: Ding Yahong
Published: October 2020

At present, it is difficult to quantify the performance of public management teaching practice. Inviewof this, based on artificial intelligence technology, this study imitates the economic performance evaluation method to introduce evaluation parameters, and adopts the analogy method to introduce the artificial intelligence economic performance evaluation system into the model proposed in this study. Moreover, this study combines with actual teaching needs to build a performance analysis model of public management teaching training based on artificial intelligence technology. In addition, this study uses a B/S structure to build the system, set functional modules based on demand analysis, and use an expert system to score. In order to study system performance and system stability in the context of big data, the system performance is studied through actual scoring and large amounts of data training. The research results show that the model proposed in this paper has a certain effect.
Reliability computation for an uncertain PVC window production system using a modified bayesian estimation
Authors: Gholizadeh Hadi , Fazlollahtabar Hamed , Khalilzadeh Mohammad
Published: October 2020

Nowadays, Industries have been receiving much attention in Failure modelling and reliability assessment of repairable systems due to the fact that it plays a crucial role in risk and safety management of process. The primary purpose of this article is to present a methodology for discussing uncertainty in the reliability assessment if the production system. In fact, we discuss the fuzzy E-Bayesian estimation of reliability for PVC window production system. This approach is used to create the fuzzy E-Bayesian estimations of system reliability by introducing and applying a theorem called “Resolution Identity” for fuzzy sets. To be more specific, the model parameters are assumed to be fuzzy random variables. For this purpose, the original problem is transformed into a nonlinear programming problem which is divided into four sub-problems to simplify the computations. Finally, the results obtained for the sub-problems can be used to determine the membership functions of the fuzzy E-Bayesian estimation of system reliability. To clarify the proposed model, a practical example for PVC window production system is conducted.
Uncertain production risk process with breakdowns and its shortage index and shortage time
Authors: Lio Waichon , Jia Lifen
Published: October 2020

Since the practical production is not continuously available and sometimes suffers unexpected breakdowns, this paper applies uncertainty theory to introducing an uncertain production risk process with breakdowns to handle the production problem with uncertain cycle times (consisting of uncertain on-times and uncertain off-times) and uncertain production amounts. The concept of shortage index of the uncertain production risk process with breakdowns is provided and some formulas for the calculation are given. Furthermore, the shortage time of the uncertain production risk process with breakdowns is proposed and its uncertainty distribution is obtained. Finally, some numerical examples are revealed.
An evolution model of risk preference influenced by extremists in large group emergency consensus process
Authors: Cao Jing , Xu Xuan-hua , Dai Fei , Pan Bin
Published: October 2020

This study uses opinion dynamics to explore the influence of extremists in the consensus process of large group decision-making. When moderates are exposed to extremists, their risk preference will be affected. By using the opinion leader theory for reference, the influence model of extremists is constructed. To better study the influence of extremists, the similarity of risk preference between extremists and moderates is modeled to measure their similarity degree. From this model, for every moderate, the extremists are divided into two groups: homogeneous group and heterogeneous group. Finally, the risk preference evolution model is structured by considering that moderates change their risk preference dynamically according to their initial preference, their attitude towards the homogeneous groups, and the heterogeneous groups. Finding from data analysis shows that moderates with high acceptance toward the influence of extremists are more likely to reach group consensus. It is also found that the preference trend of moderates with a certain degree of acceptance toward heterogeneous groups fluctuates with a ‘W’ shape. This study bridges the gap between opinion dynamics and group decision making. Meanwhile, the model inspires new explanations and new perspectives for the group consensus process.
Product form evolutionary design system construction based on neural network model and multi-objective optimization
Authors: Wu Yixiang
Published: October 2020

The product form evolutionary design based on multi-objective optimization can satisfy the complex emotional needs of consumers for product form, but most relevant literatures mainly focus on single-objective optimization or convert multiple-objective optimization into the single objective by weighting method. In order to explore the optimal product form design, we propose a hybrid product form design method based on back propagation neural networks (BP-NN) and non-dominated sorting genetic algorithm-II (NSGA-II) algorithms from the perspective of multi-objective optimization. First, the product form is deconstructed and encoded by morphological analysis method, and then the semantic difference method is used to enable consumers to evaluate product samples under a series of perceptual image vocabularies. Then, the nonlinear complex functional relation between the consumers’ perceptual image and the morphological elements is fitted with the BP-NN. Finally, the trained BP-NN is embedded into the NSGA-II multi-objective evolutionary algorithm to derive the Pareto optimal solution. Based on the hybrid BP-NN and NSGA-II algorithms, a multi-objective optimization based product form evolutionary design system is developed with the electric motorcycle as a case. The system is proved to be feasible and effective, providing theoretical reference and method guidance for the multi-image product form design.
Hilbert stereo reconstruction algorithm based on depth feature and stereo matching
Authors: Kong Weiyi , Yang Menglong , Huang Qinzhen
Published: October 2020

This paper proposes a Hilbert stereo reconstruction algorithm based on depth feature and stereo matching to solve the problem of occlusive region matching errors, namely, the Hilbert stereo network. The traditional stereo network pays more attention to disparity itself, leading to the inaccuracy of disparity estimation. Our design network studies the effective disparity matching and refinement through reconstruction representation of Hilbert’s disparity coefficient. Since the Hilbert coefficient is not affected by the occlusion and texture in the image, stereo disparity matching can conducted effectively. Our network includes three sub-modules, namely, depth feature representation, Hilbert cost volume fusion, and Hilbert refinement reconstruction. Separately, texture features of different depth levels of the image were extracted through Hilbert filtering operation. Next, stereoscopic disparity fusion was performed, and then Hilbert designed to refine the difference regression stereo matching solution was used. Based on the end-to-end design, the structure is refined by combining the depth feature extraction module and Hilbert coefficient disparity. Finally, the Hilbert stereo matching algorithm achieves excellent performance on standard big data set and is compared with other advanced stereo networks. Experiments show that our network has high accuracy and high performance.
[123I]FP-CIT SPECT in Clinically Uncertain Parkinsonism Predicts Survival: A Data-Driven Analysis
Authors: Frings Lars , Henninger Franziska , Treppner Martin , Köber Göran , Boeker Martin , Hellwig Sabine , Buchert Ralph , Meyer Philipp T.
Published: October 2020

Background: Dopamine transporter SPECT is an established method to investigate nigrostriatal integrity in case of clinically uncertain parkinsonism. Objective: The present study explores whether a data-driven analysis of [123I]FP-CIT SPECT is able to stratify patients according to mortality after SPECT. Methods: Patients from our clinical registry were included if they had received [123I]FP-CIT SPECT between 10/2008 and 06/2016 for diagnosis of parkinsonism and if their vital status could be determined in 07/2017. Specific binding ratios (SBR) of the whole striatum, its asymmetry (asymmetry index, AI; absolute value), and the rostrocaudal gradient of striatal binding (C/pP: caudate SBR divided by posterior putamen SBR) were used as input for hierarchical clustering of patients. We tested differences in survival between these groups (adjusted for age) with a Cox proportional hazards model. Results: Data from 518 patients were analyzed. Median follow-up duration was 3.3 years [95% C.I. 3.1 to 3.7]. Three subgroups identified by hierarchical clustering were characterized by relatively low striatal SBR, high AI, and low C/pP (group 1), low striatal SBR, high AI, and high C/pP (group 2), and high striatal SBR, low AI, and low C/pP (group 3). Mortality was significantly higher in group 1 compared to each of the other two groups (p = 0.029 and p = 0.003, respectively). Conclusion: Data-driven analysis of [123I]FP-CIT SPECT identified a subgroup of patients with significantly increased mortality during follow-up. This suggests that [123I]-FP-CIT SPECT might not only serve as a diagnostic tool to verify nigrostriatal degeneration but also provide valuable prognostic information.
Study on Effect of Electromagnetic Characteristics of Deformed 304 Stainless Steel on Eddy Current Testing
Authors: Wan Benli , Hu Bin , Li Yuntao , Zhu Yuhong
Published: October 2020

The induced ferrite and other high magnetic microstructures content changes are studied when 304 austenitic stainless steel stripe specimens are tested under different uniaxial tension deformation, namely its deformation less than 50%. Furtherly, the correlation is plotted between the resulting magnetic permeability or coercivity caused by these microstructures and deformation. Meanwhile, the optimal eddy current excitation frequency under different deformation was obtained, which was consistent with 3-D finite element analysis (FEA). Besides, other various factors affecting the quality of eddy current testing (ECT), such as temperature and conductivity, are also considered comprehensively during the tensile test. The results of the experiment and simulation calculation show that when the deformation is within 50% that necking deformation has occurred, the magnetic permeability of specimens increases with deformation, and gradually begin to have the magnetic properties of weak ferromagnetic materials, which also changes the optimal excitation frequency, which varies from 60 kHz to 110 kHz. Because of the electromagnetic response noise increase, the impedance plane diagrams of defects distort simultaneously, which leads to the quantitative evaluation error of defects.
Research on Analysis of Eddy Current Response to Lay Length of Wire Ropes
Authors: Jiao Shaoni , Jia Xiaojuan , Li Tengyu , Jin Shukui , Kou Ziming , Wu Juan , Kou Yanfei
Published: October 2020

The lay length is one of the important parameters for the wire rope and its detection can indirectly characterize its stress and surface damage state. The eddy current testing (ECT) method is advantageous because of its easy operation, single-side detection, low requirement of surface preparation, applicability in harsh environment, and other properties. Hence the lay length of the wire ropes is measured by ECT in this paper. The eddy current (EC) response to the wire rope is simulated. The EC on the surface of the strand below the pancake coil forms a vortex, and the distribution of the EC on the curved surfaces on both sides of the strand is symmetrical. The spacing between the adjacent peaks or troughs of the scanning signal is the distance between the adjacent strands, and the number of peaks or troughs of the scanning signal in a range of the lay length is related to the number of strands of the wire rope. Finally, the experimental validation is performed. The relative error of the lay length of the wire rope assessed by the EC method is less than 0.28%.
Capacitive Imaging for Adhesive Bonds and Quality Evaluation
Authors: Huang Xuhui , Hamilton Ciaron , Li Zonglin , Udpa Lalita , Udpa Satish S. , Deng Yiming
Published: October 2020

Defective adhesive bonds pose significant threats towards structural integrity due to reduced joint strength. While the nature of the adhesion of two solids remains poorly understood since adhesion phenomenon is relevant to so many scientific and technological areas. A concept that has been gaining our attention from the perspective of nondestructive testing is the properties discontinuity of the adhesion. Discontinued properties depend significantly on the quality of the interface that is formed between adhesive and substrate. In this research, discontinued electrical properties at the interface are considered. The simplified model is free from multidisciplinary knowledge of chemistry, fracture mechanics, mechanics of materials, rheology and other subjects. From a practical standpoint, this emphasizes the need to establish a good relationship between electrical properties of adhesive bonds and corresponding measurements. Capacitive Imaging (CI) is a technique where the dielectric property of an object is determined from external capacitance measurements. Thus, it is potentially promising since adhesive and substrate differ in terms of dielectric property. At the interface between adhesive and substrate, discontinuity of the dielectric properties causes abrupt changes in electric field spatial distribution and thus alters capacitance measurement. By simulating defects in adhesive joints regarding permittivity uncertainties. Further understanding of the cause of degraded adhesion quality can be obtained
Design of Power Grid Intelligent Patrol Operation and Maintenance System Based on Multi-Rotor UAV Systems
Authors: Liu Qunying , Zeng Haifeng , Ni Shaojian , Li Bowen , Meng Jingsong , Zhang Yiguo
Published: October 2020

Complex geographical conditions and bad weather have caused great difficults to inspect transmission line of power grids. This work aims to develop a micro multi-rotor Unmanned Aerial Vehicle (UAV) system for inspecting power grid. The proposed system integrates with an intelligent robot and mobile communication networks. The high-resolution aerial images of the inspection line can be obtained to improve the operational efficiency and safety. The time period from the front-end signal acquisition to terminal decoding and playback is 1.5s for condition-based maintenance. The system supports TDD-LTE, FDD-LTE, WCDMA, CDMA2000, and other network standards. It also supports the video input signals with the resolution of standard 576i, HD 720p, FHD 1080i, and FHD 1080p. It is compatible with a variety of transmission formats and codes, help to achieve timely, comprehensive and efficient high-resolution aerial image acquisition of patrol lines, and improve operational efficiency and safety, real-time monitoring and condition-based maintenance of power transmission lines.
Impact Damages Detection on CFRP Using Eddy Current Pulsed Thermography
Authors: Ba Abdoulaye , Yi Qiuji , Zhu Junzhen , Bui Huu-Kien , Tian Gui Yun , Berthiau Gérard , Wasselynck Guillaume
Published: October 2020

Carbon Fiber Reinforced Polymer (CFRP) materials are widely used in aerospace due to their low weigh to strength ratio. Non-destructive Testing (NDT) Techniques becomes a necessity with increasing use of CFRP materials. Induction Thermography is a new NDT technique that can be exploited as a promising fast and global control. However, the detection of typical flaws in carbon composites such as delamination, fibers rupture and impact damages need to be further investigated in order to optimize the technique. Optimization can be done in the test configuration level and by the use an appropriate image technique. In this paper Eddy Current Pulse Compression Thermography (ECPuCT) is used to detect impact damages on CFRP materials. The Principal Component Analysis (PCA) based image processing technique is used to detect and visualize impact damage area from transient thermal images. Flaw detection results using experimental measures will be shown and discussed.
Dependence of Coercivity and Barkhausen Noise Signal on Martensitic Stainless Steel with and without Quench
Authors: Kikuchi Hiroaki , Sugai Kohei , Murakami Takeshi , Matsumura Keiichi
Published: October 2020

We evaluated hysteresis curves and Barkhausen noise properties of the martensitic stainless steel with and without quench, and then investigated the relations between magnetic parameters and hardness based on microstructure changes. The quench introduced to reduce grain size, which relates to an increment of coercivity and Vickers hardness, a decrease in Barkhausen signal. The magnetic property changes reflect the changes in microstructures and mechanical property appeared on the quenched specimen. The obtained results contribute to aim to develop a magnetic nondestructive evaluation of residual stress appeared on the ferromagnetic steel combined with and without quench.
An Investigation of Corrosion Progression Using Laser Profilometry
Authors: Zhang Hong , Wu Ruikun
Published: October 2020

Atmospheric corrosion progression characterisation on metal substrates is a major problem in the field of corrosion science and Non-destructive Evaluation (NDE). A laser profilometry has been used to characterise the corrosion on the mild steel plate at a low cost and high resolution. Four mild steel samples have been measured which exposed to the marine environment from 1 month to 10 months. Two features have been developed to characterise thickness variation in the corrosion layer. These features have been used to characterise corrosion progression through experimental studies. The relationship between these features and corrosion progression has been derived which is useful for corrosion progression measurement, early-stage corrosion prediction, and monitoring areas.
A Parallel Wire Cable Tension Testing Method Based on a Permanent Magnetizer
Authors: Liu Youwei , Wu Xinjun
Published: October 2020

Obtaining the cable tension accurately is important to the structural safety. Among different cable tension testing methods, the method of testing stress under the excitation of constant magnetic field is not affected by the boundary condition of the cable and avoids the affection of eddy current. Through analyzing the structural features of parallel wire cable, a cable tension testing method is presented based on the principle of testing stress under the excitation of constant magnetic field. An experiment setup is carried out to verify the feasibility of the method.
Passive Method for Monitoring Atmospheric Phenomena by Evaluating the Cellular Network Signals
Authors: Kuba Michal , Fabo Peter , Podhorský Dušan , Faktorová Dagmar , Savin Adriana
Published: October 2020

An integral part of our environment in addition to the surface of the Earth is the adjacent part of the atmosphere, the lower layer of the troposphere. This part of the troposphere has essential influence on weather evolution and information on its condition is an important part of the weather forecasting models. Standard methods of the data acquisition such as radars, satellites and weather stations do not provide information with sufficiently high temporal and spatial resolution. The subject of the article is a method of monitoring the condition of lower layers of the troposphere by passive monitoring and evaluation the parameters of cellular network signals. The elementary theory of an virtual sensor for the atmospheric radio refractive index monitoring and the preliminary results of experimental monitoring of the selected meteorological situation are presented.
Menière’s disease caused by CGRP - A new hypothesis explaining etiology and pathophysiology. Redirecting Menière’s syndrome to Menière’s disease
Authors: Hegemann Stefan Carl Anton
Published: October 2020

This paper provides a new hypothetical explanation for the etiopathology and pathophysiology of Menière’s Disease (MD), which to date remain unexplained, or incompletely understood. The suggested hypothesis will explain the close connection of MD and Migraine, the coexistence of endolymphatic hydrops (ELH) and Menière attacks and the signs of inflammation detected in the inner ears of MD patients. Although as yet unproven, the explanations provided appear highly plausible and could pave the way for the generation of the first animal model of MD – an invaluable asset for developing new treatment strategies. Furthermore, if proven correct, this hypothesis could redefine and also reset the actual name of Menière’s Syndrome to Menière’s Disease.
Are gain values significantly altered by manual data selection when performing the video Head Impulse Test (v-HIT) on all six semicircular canals with two different v-HIT systems
Authors: Abrahamsen Emil Riis , Skals Regitze Kuhr , Hougaard Dan Dupont
Published: October 2020

BACKGROUND: It has not yet been tested whether averaged gain values and the presence of pathological saccades are significantly altered by manual data selection or if data selection only done by the incorporated software detection algorithms provides a reliable data set following v-HIT testing. OBJECTIVE: The primary endpoint was to evaluate whether the averaged gain values of all six SCCs are significantly altered by manual data selection with two different v-HIT systems. METHOD: 120 subjects with previously neither vestibular nor neurological disorders underwent four separate tests of all six SCCs with either EyeSeeCam® or ICS Impulse®. All v-HIT test reports underwent manual data selection by an experienced ENT Specialist with deletion of any noise and/or artifacts. Generalized estimating equations were used to compare averaged gain values based on unsorted data with averaged gain values based on the sorted data. RESULTS: EyeSeeCam®: Horizontal SCCs: The estimate and the p-value (shown in parenthesis) for the right lateral SCC and the left lateral SCC were 0.00004 (0.95) and 0.00087 (0.70) respectively. Vertical SCCs: The estimate varied from –0.00858 to 0.00634 with p-values ranging from 0.31 to 0.78. ICS Impulse®: Horizontal SCCs: The estimate and the p-value for the right lateral SCC and the left lateral SCC were 0.00159 (0.18) and 0.00071 (0.38) respectively. Vertical SCCs: The estimate varied from 0.00217 to 0.01357 with p-values ranging from 0.00 to 0.17. Based upon the averaged gain value from the individual SCC being tested, 148 tests before and 127 after manual data selection were considered pathological. CONCLUSION: None of the two v-HIT systems revealed any clinically important effects of manual data selection. However, 21 fewer tests were considered pathological after manual data selection.
РОЗВИТОК І СТАНОВЛЕННЯ СИСТЕМИ КОНТРОЛЮ ІНФЕКЦІЙНИХ ЗАХВОРЮВАНЬ ДО ХХ СТОЛІТТЯ
Authors: Hrynzovskyi Anatolii
Published: October 2020

У цій роботі ми розглянули створення та розвиток національних та місцевих органів влади, завданням яких було забезпечення та реалізація національної політики щодо запобігання виникненню та поширенню інфекційних захворювань. Вивчалися повноваження органів державного та місцевого самоврядування в структурі системи контролю за поширенням інфекційних хвороб у російській імперії до початку ХХ століття. Показано відносний вплив розвитку медичної науки, міжнародної торгівлі на прийняття міжнародних санітарних конвенцій та розроблення нових правових документів у галузі профілактичної медицини та їх впровадження у структуру законодавства Російської імперії. Значення сільських та місь- ких реформ (1864) для розвитку профілактичної медицини. Створення умов для формування у структурі професійних установ місцевого самоврядування, відповідальних за санітарну та протиепідемічну роботу на територіальному рівні. Показано, що зі створенням нових форм самоврядування шляхи розвитку боротьби з інфекціями в сільській та міській медицині відносно відрізняються, насамперед, від специфічних умов життя та праці сільського та міського населення, до тяжкості дій тих факторів ризику, які вплинули на санітарно-епідеміологічний добробут населення.
РІВЕНЬ СЕРОТОНІНУ У ХВОРИХ НА ГЕНЕРАЛІЗОВАНИЙ АТЕРОСКЛЕРОЗ ТА ЙОГО ДИНАМІКА ПІД ВПЛИВОМ ЦИЛОСТАЗОЛУ
Authors: Motsak Tatiana , Lizogub Victor , Kupchynska Elena , Bugaytsev Alexey
Published: October 2020

Метою даної роботи є вивчення впливу цилостазолу на регіональну гемодинамі- ку, рівень серотоніну та функціональну активність мозку, серця, нижніх кінцівок у хворих на генералізований атеросклероз. У 12-тижневе відкрите рандомізоване плацебо-контрольоване дослідження було включено 52 осіб чоловічої статі з генералізованим атеросклерозом та 26 осіб чоловічої статі з хронічним коронарним синдромом (група порівняння). Пацієнти основної групи, які мали генералізований атеросклероз були рандомізовані на дві підгрупи: 26 чоловіків додатково до базисної терапії отримували цилостазол в дозі 100 мг двічі на добу та 26 паці- єнтів, які додатково отримували плацебо. Пацієнти з генералізованим атеросклерозом мали ураження чотирьох судинних басейнів: церебрального, коронарного, мезентеріального та ниж- ніх кінцівок. Виявлено, що у хворих на генералізований атеросклероз рівень серотоніну в плазмі крові перевищував показник групи порівняння в 7,8 рази, а ряд інших показників, таких як: показники об’ємного кровотоку (р<0,001), когнітивної функції, дистанції безбольової ходьби, були нижче групи порівняння. Під впливом лікування, з додаванням цилостазолу протягом 12 тижнів до базисної терапії, стан показників покращився: рівень серотоніну в плазмі зменшив- ся в 2,9 рази (р<0,001), достовірно (р<0,001) збільшився об’ємний кровотік в усіх досліджуваних судинних басейнах, що сприяло зменшенню кількості як больових, так і безбольових епізодів ішемії міокарда (за даними добового електрокардіографічного моніторування), збільшенню безбольової та максимальної дистанції ходьби та поліпшенню когнітивної функції головного мозку. У групі пацієнтів з генералізованим атеросклерозом, які приймали плацебо, під впли- вом лікування зміни були не достовірні. Отримані нами дані вказують на позитивний вплив цилостазолу як доповнення до базисної терапії у хворих на генералізований атеросклероз та важливість проведення подальших досліджень у даному напрямку.