bluuebunny/crossref_metadata_2025 huggingface dataset:
Ecohydrological Behavior of Semiarid Ecosystems of Chile in Present and Future Climate Scenarios
Authors: Parra Javier Lo , Garrido Velarde Jacinto , González Jesus Barrena , Fernández Manuel Pulido
Published: February 2021

Semiarid ecosystems of Chile with Mediterranean climate support high demographic rates and maintain important economies associated with the productivity of the natural environment; however, they strongly depend on the water availability and their future is compromised by climate variations. This study tries to define the role of hydrological variables on the growth of herbaceous biomass under the current climate and under future weather variations. For this, the authors used meteorological stations which let them estimate the water balance at plot scale and spectral reflectance sensors which let them follow the dynamics of the NDVI of herbaceous plants. In this context, the NDVI value was about 0.7, which means approximately 3700 kg DM ha1. However, under the worst-case climate change scenarios (RCP 8.5), annual precipitation showed a reduction of up to 31.6% regarding the present period. In this situation, the NDVI could be reduced up to 80% respect to the current situation. Thus, if climate changes to its worst scenario, it could threaten the maintenance and productivity of these ecosystems.
Tourism and Economic Growth Nexus
Authors: Durgun Özlem
Published: February 2021

Increasing the competitiveness of the tourism industry of the Mediterranean countries by creating more and better jobs with the sustainable growth of tourism is the main goal of all countries. However, the development of tourism in the Mediterranean countries and the effects are not compatible with each other. This chapter will explain tourism and economic growth nexus: the case of Mediterranean countries. The first part of the study examined the contribution of tourism to the world economy, and then the Mediterranean region were discussed. When the contributions were analyzed, it was determined that North and South are divided into two. By demonstrating that the environmental effects of growth in tourism are different, policy recommendations have been made to these two separate Mediterranean regions.
Achieving Seafood Security in the Mediterranean Region
Authors: Yıldırım Seda , Yıldırım Durmuş Cagrı
Published: February 2021

The last decade has shown that food security is a major problem in the long term. Especially, food insecurity will be higher in poor and developing countries when the rising population needs more food sources. In this point, seafood products seem an alternative solution to achieve food security in the global food market. The Mediterranean region, which has lots of benefits from seafood market and fisheries, gives more attention to seafood security. Achieving seafood security is an important issue for coastal countries. This study aims to explain the importance of seafood security in the Mediterranean region through case of Turkey. The open access data from TURKSTAT (Turkish Statistical Institute) and FAO (Food and Agriculture Organization of the United Nations) were used to determine seafood security conditions in Turkey. The study presents significant findings showing the role of seafood security in Mediterranean region in the context of sustainable development approach.
Measuring the Effect of Wage Inequality on Income Distribution via Theil Index in the Manufacturing Industry of Spain-Portugal
Authors: Soylu Özgür Bayram , Orhan Ayhan , Emikönel Murat
Published: February 2021

Income distribution is defined as sharing income arising from the sale of products among persons, groups, or production factors in a country within specific periods. Income inequality is the wage gaps between persons, groups, or regions. Increasing income inequality is accepted as the primary problem of economies in terms of bringing along many problems. This is because the fair distribution has continued to remain on the agenda of economic policies. There are several methods in measuring the inequality in the distribution of income as well as this study utilized Theil index because of the sensitivity of related index to super and subgroups of the income distribution. Spain and Portugal, in this chapter, were accepted as a single county; Spain and Portugal (each) were accepted as the regions of this presumptive country. Under this assumption, the course of wages inequality in time was revealed by the inequality analysis that was performed for eight sub-sectors of the manufacturing sector of Spain and Portugal for the years between1995 and 2015.
Exploring the Role of Microfinance in Emerging Nations
Authors: Kasemsap Kijpokin
Published: February 2021

This chapter explains the overview of microfinance; the efficiency of microfinance institutions (MFIs) and sustainability; microfinance and interest rates; microfinance and information technology (IT); microfinance, social capital, trust, and repayment rates; microfinance and health care; informal microfinance institutions (IMFIs) and tourism entrepreneurship; and the importance of microfinance in emerging nations. Financial services provide a method for people and businesses to obtain credit and manage available assets on a continuous basis. Microfinance has a significant role in bridging the gap between formal financial institutions and rural poor households. MFIs can access financial resources from banks and other financial institutions and provide financial services to poor households. The chapter argues that promoting microfinance has the potential to enhance financial performance and reach economic goals in emerging nations.
The Quest for Financial Inclusion and Microfinance Institutions in India
Authors: Manzoor Amir
Published: February 2021

Financial inclusion refers to providing unconditional and affordable access to financial services in an effective and efficient manner for all needy people. Microfinance institutions (MFIs) play an important role in financial inclusion and societal development. One important part of the financial inclusion strategy is to provide access to finance to those people belonging to remote and disadvantaged areas. The aim of this chapter is to study the concept of microfinance and microfinance institutions and its impact on financial inclusion in India. This study provides recommendations to grow and sustain microfinance institutions to achieve greater financial inclusion.
Analytical Model and Computing Optimization of a Compliant Gripper for the Assembly System of Mini Direct-Current Motor
Authors: Le Chau Ngoc , Ho Nhat Linh , Tran Ngoc Thoai , Dao Thanh-Phong
Published: February 2021

This study proposes a combination of kinematics-based design method, statistic method, and TLBO algorithm to solve computing optimization for a compliant gripper. It is employed in an assembly system of mini direct current motor. First, the kinematic models of the gripper are developed. The static model is paid attention. Next, the dynamic model is established based on Lagrange's principle. Then, a multi-criteria optimization for the gripper is conducted by Taguchi method integrated with TLBO algorithm. Finally, the FEA and experiments are implemented to verify the optimal results and evaluate the performances of the compliant gripper. The results indicated that theoretical models are in good accord with the results from simulations and experiments. Additionally, the performance of the present method is superior to PSO algorithm. The results revealed that the compliant gripper allows a displacement up to 3000 µm and the amplification ratio of 12 times. The compliant gripper is a potential application for the mini direct-current motor assembly system.
Autonomous Unmanned Aerial Vehicle for Post-Disaster Management With Cognitive Radio Communication
Authors: Raja Guru R.  , Naresh Kumar P.
Published: February 2021

Unmanned aerial vehicles (UAV) play a significant role in finding victims affected in the post-disaster zone, where a man cannot risk his life under a critical condition of the disaster environment. The proposed design incorporates autonomous vision-based navigation through the disaster environment based on general graph theory with dynamic changes on the length between two or multiple nodes, where a node is a pathway. Camera fixed on it continuously captures the surrounding footage, processing it frame by frame on-site using image processing technique based on a SOC. Identifies victims in the zone and the pathways available for traversal. UAV uses an ultrasonic rangefinder to avoid collision with obstacles. The system alerts the rescue team if any victim detected and transmits the frames using CRN to the off-site console. UAV learns navigation policy that achieves high accuracy in real-time environments; communication using CRN is uninterrupted and useful during such emergencies.
Designing and Modelling of Delta Wing Genetic-Based Prediction Model
Authors: Arun M. P.  , Satheesh M.  , Dhas J. Edwin Raja
Published: February 2021

The designing and modeling of delta wing is one of the interesting topics. A number of researchers has contributed different works on modeling the same. This paper comes out with a new delta wing modeling with the inclusion of optimization concept. The obtained data from the investigation is integrated and given as the input to the classifier for predicting the drag and lift coefficients. This paper uses neural network (NN) classifier for predicting the drag and lift coefficients. Moreover, the weight of the NN is optimized using a proposed genetic algorithm. After the implementation, the performance of proposed model is compared to other conventional methods like individual adaptive genetic algorithm (IAGA-NN), deterministic adaptive genetic algorithm (DAGA-NN), self-adaptive genetic algorithm (SAGA-NN), genetic algorithm (GA-NN), gradient descendent (GD-NN), and Levenberg masquerade (LM-NN), respectively, in terms of drag and lift coefficient.
Relationship Between Speed of Performing Leg Extension With 30 RM Load and the Selected EMG Variables of Selected Quadricep Muscles
Authors: Shaw Dhananjoy , Singh Deepak , Ahlawat Umesh Kumar , Kaur Manvinder , Bhatia Dinesh
Published: February 2021

The aim of the study was to assess the effects of speed of leg extension exercise with 30 RM load on the EMG activity of Vastus Medialis (VM) and Vastus Lateralis (VL). Seventeen healthy male subjects performed 30 repetition of leg extension exercise with 30 RM load in minimum time possible and EMG activity from VM and VL of right lower extremity was recorded simultaneously. Two new criteria, namely gross load speed of movement (GLSM) and relative load speed of movement (RLSM) were developed as the variables of speed of exercise. Selected variables of EMG activity were median frequency (MDF), mean frequency (MNF), root mean square (RMS), and integrated EMG (IEMG). Product moment and rank order correlation were calculated between the selected variables of EMG activity and selected variables of speed of exercise. The selected EMG variables, namely MDF and MNF, reported a negative significant relationship (p<0.05) with selected variables of speed of exercise whereas a selected EMG variables, namely RMS reported a positive significant relationship (p<0.05) with selected with the selected variables of speed of exercise.
Reconstruction of EIT Images Using Fish School Search and Non-Blind Search
Authors: Barbosa Valter Augusto de Freitas , Ribeiro David Edson , Lins de Lima Clarisse , Araújo de Santana Maíra , Emmanuel de Souza Ricardo , Pinheiro dos Santos Wellington
Published: February 2021

Breast cancer is the most common type of cancer among women, affecting 2.1 million women per year worldwide. The best strategy for decreasing disease morbidity and mortality is early detection. Mammography is the most used exam for the diagnosis of breast cancer. However, this technique uses ionizing radiation and causes discomfort to the patient. One promising technique that can be used for early detection of breast cancer is electrical impedance tomography (EIT), which is an imaging technique free of ionizing radiation. Yet, its images still have low resolution, making it difficult to use in breast cancer diagnosis. Thus, the development of new reconstruction methods aiming better resolution is necessary. This work evaluates the performance of the reconstruction algorithm based on fish school search with non-blind search in a 3,190 finite element mesh.
Cyberbullying Among Adolescent Students in Light of Some Demographic Variables
Authors: Khaled Mohammed Soleiman Bani , Al-Adamat Omar Atallah
Published: February 2021

This study aims to identify the level of cyberbullying among a sample consisting of teenager students in the city of Mafraq in Jordan. It also aims to identify the differences at the level of cyberbullying in terms of gender, educational level, and academic achievement. The sample of the study was composed of 160 male and female students randomly selected from four schools of the education directorate in the northeast desert in 2020. Cyberbullying scale was employed in this research. The results revealed that the level of cyberbullying among adolescent students was moderate. Findings also suggested that there are differences at the level of cyberbullying between students in terms of gender, educational level, and academic achievement. In addition, the results suggested differences between the participants attributed to the interaction between gender and academic achievement and the interaction between educational level and academic achievement.
Fuzzy Bayesian Context-Aware System to Reduce Electricity Consumption
Authors: Shirsat Kavita Pankaj , Bhole Girish P.
Published: February 2021

Context-awareness develops smart, intelligent IoT devices that can adapt to changing needs and act autonomously on behalf of the user. The main challenge of context-aware internet of things is to interpret the context effectively. There is an abundance of CAIOT in literature. Understanding of the meaning of the context is, however, almost ignored. Misinterpretation of context can lead to an incorrect decision that motivates to develop a system that emphasis context reasoning and decision making using the fuzzy Bayesian approach. The current investigation aims to build a context-aware IoT system using occupancy detection for energy management. The performance evaluation for the proposed system uses data collected in the tutorial room to detect occupancy. Extensive experiments highlight the utility of the proposed approach, which significantly reduces energy than the traditional ON/OFF usage pattern through customer access via mobile phone or personal computer.
Perspectives of Fuzzy Logic and Their Applications
Authors: Mewada Shivlal
Published: February 2021

Fuzzy logic is a highly suitable and applicable basis for developing knowledge-based systems in engineering and applied sciences. The concepts of a fuzzy number plays a fundamental role in formulating quantitative fuzzy variable. These are variable whose states are fuzzy numbers. When in addition, the fuzzy numbers represent linguistic concepts, such as very small, small, medium, and so on, as interpreted in a particular contest, the resulting constructs are usually called linguistic variables. Each linguistic variable the states of which are expressed by linguistic terms interpreted as specific fuzzy numbers is defined in terms of a base variable, the value of which are real numbers within a specific range. A base variable is variable in the classical sense, exemplified by the physical variable (e.g., temperature, pressure, speed, voltage, humidity, etc.) as well as any other numerical variable (e.g., age, interest rate, performance, salary, blood count, probability, reliability, etc.). Logic is the science of reasoning. Symbolic or mathematical logic is a powerful computational paradigm. Just as crisp sets survive on a 2-state membership (0/1) and fuzzy sets on a multistage membership [0 - 1], crisp logic is built on a 2-state truth-value (true or false) and fuzzy logic on a multistage truth-value (true, false, very true, partly false and so on). The author now briefly discusses the crisp logic and fuzzy logic. The aim of this paper is to explain the concept of classical logic, fuzzy logic, fuzzy connectives, fuzzy inference, fuzzy predicate, modifier inference from conditional fuzzy propositions, generalized modus ponens, generalization of hypothetical syllogism, conditional, and qualified propositions. Suitable examples are given to understand the topics in brief.
Ranking News Feed Updates on Social Media
Authors: Belkacem Sami , Boukhalfa Kamel
Published: February 2021

Social media are used by hundreds of millions of users worldwide. On these platforms, any user can post and share updates with individuals from his social network. Due to the large amount of data, users are overwhelmed by updates displayed chronologically in their newsfeed. Moreover, most of them are irrelevant. Ranking newsfeed updates in order of relevance is proposed to help users quickly catch up with the relevant updates. In this work, the authors first study approaches proposed in this area according to four main criteria: features that may influence relevance, relevance prediction models, training and evaluation methods, and evaluation platforms. Then the authors propose an approach that leverages another type of feature which is the expertise of the update's author for the corresponding topics. Experimental results on Twitter highlight that judging expertise, which has not been considered in the academic and the industrial communities, is crucial for maximizing the relevance of updates in newsfeeds.
Enhancing Data Quality at ETL Stage of Data Warehousing
Authors: Gupta Neha , Jolly Sakshi
Published: February 2021

Data usually comes into data warehouses from multiple sources having different formats and are specifically categorized into three groups (i.e., structured, semi-structured, and unstructured). Various data mining technologies are used to collect, refine, and analyze the data which further leads to the problem of data quality management. Data purgation occurs when the data is subject to ETL methodology in order to maintain and improve the data quality. The data may contain unnecessary information and may have inappropriate symbols which can be defined as dummy values, cryptic values, or missing values. The present work has improved the expectation-maximization algorithm with dot product to handle cryptic data, DBSCAN method with Gower metrics to ensure dummy values, Wards algorithm with Minkowski distance to improve the results of contradicting data and K-means algorithm along with Euclidean distance metrics to handle missing values in a dataset. These distance metrics have improved the data quality and also helped in providing consistent data to be loaded into a data warehouse.
Fingerprint Presentation Attack Detection Using Transfer Learning Approach
Authors: Rani Rajneesh , Singh Harpreet
Published: February 2021

In this busy world, biometric authentication methods are serving as fast authentication means. But with growing dependencies on these systems, attackers have tried to exploit these systems through various attacks; thus, there is a strong need to protect authentication systems. Many software and hardware methods have been proposed in the past to make existing authentication systems more robust. Liveness detection/presentation attack detection is one such method that provides protection against malicious agents by detecting fake samples of biometric traits. This paper has worked on fingerprint liveness detection/presentation attack detection using transfer learning for which the authors have used a pre-trained NASNetMobile model. The experiments are performed on publicly available liveness datasets LivDet 2011 and LivDet 2013 and have obtained good results as compared to state of art techniques in terms of ACE(average classification error).
A Discriminative Locality-Sensitive Dictionary Learning With Kernel Weighted KNN Classification for Video Semantic Concepts Analysis
Authors: Ghansah Benjamin , Benuwa Ben-Bright , Monney Augustine
Published: February 2021

Video semantic concept analysis has received a lot of research attention in the area of human computer interactions in recent times. Reconstruction error classification methods based on sparse coefficients do not consider discrimination, essential for classification performance between video samples. To further improve the accuracy of video semantic classification, a video semantic concept classification approach based on sparse coefficient vector (SCV) and a kernel-based weighted KNN (KWKNN) is proposed in this paper. In the proposed approach, a loss function that integrates reconstruction error and discrimination is put forward. The authors calculate the loss function value between the test sample and training samples from each class according to the loss function criterion, and then vote on statistical results. Finally, this paper modifies the vote results combined with the kernel weight coefficient of each class and determine the video semantic concept. The experimental results show that this method effectively improves the classification accuracy for video semantic analysis and shorten the time used in the semantic classification compared with some baseline approaches.
A Novel Hybrid Cyber Range for Security Exercises on Cyber-Physical Systems
Authors: Hallaq Bil , Nicholson Andrew , Smith Richard , Maglaras Leandros , Cook Allan , Janicke Helge , Jones Kevin
Published: February 2021

Incident response teams cannot prepare for every situation or predict every crisis, especially when they involve cyber-physical systems. As a result, training activities need to be provided to support operating in challenging situations to develop concrete guidance, procedures, and tools to help individuals collectively react in different, unpredictable situations. Experiential learning is a training technique based on the assumed importance of experimenting and involvement, proposing that active engagement in a scenario develops personal experiences that form the basis of understanding. Exercises are a form of serious games that are a proven method of delivering experiential learning. This article presents CYRAN, a realistic environment used for cyber warfare training, cyber resiliency testing, and cyber technology development. CYRAN is a low-cost cyber range that can be easily used for experiments on realistic scenarios for various educational and training purposes and for the collection of labelled datasets for further research.
A Low Energy MCL-Based Clustering Routing Protocol for Wireless Sensor Networks
Authors: Brahim Mohammed Taieb , Abbad Houda , Boukil-Hacene Sofiane
Published: February 2021

Wireless sensor networks (WSNs) have attracted increasing attention during the two last decades. Indeed, their applications target a wide range of fields such as healthcare, industrial control, environmental monitoring, etc. The main challenge of WSNs is the limitation of resources requiring efficient management of energy consumption. Coverage is also considered as one of the critical indicators of the quality of service (QoS) of WSNs. Therefore, the design of routing protocols should focus on energy efficiency and network coverage. In this paper, the authors propose a novel energy-efficient clustering protocol that is more efficient than some prominent routing protocols and offers better coverage of the network than LEACH. The protocol combines the MCL algorithm for cluster formation and a new cluster head selection strategy based on location and residual energy of sensors. Simulation results demonstrate that the proposed protocol is better than other protocols in terms of energy management and extending the lifetime of the network, whereas, it achieves good coverage than LEACH.
AVALIAÇÃO DA ADEQUABILIDADE DE USO E OCUPAÇÃO DE TRECHO DA BA-262, FRENTE À INSTALAÇÃO DE EMPREENDIMENTOS LOGÍSTICOS
Authors: Mendes Luis Vinicius Muniz , Gomes Ronaldo Lima
Published: February 2021

Este trabalho visa realizar a avaliação da adequabilidade de uso e ocupação do solo em trecho da BA-262, frente à instalação de empreendimentos logísticos. Para tanto, foram realizados a caracterização dos aspectos físico-ambientais e o mapeamento de uso e ocupação do solo de uma faixa de 2 km de largura por 28 km de comprimento, situada entre as cidades de Ilhéus e Uruçuca, no Estado da Bahia. Dados de rede de drenagem e de classes de uso e ocupação do solo foram obtidos a partir da interpretação de fotografias aéreas na escala de 1:2.000 e de imagens Digital Globe obtidas no Google Earth. Já os dados de Áreas de Preservação Permanentes - APP foram obtidos a partir da manipulação dos arquivos vetoriais da rede de drenagem (APP de margens de cursos d’água e nascentes) e identificação de classes de uso e ocupação, como a de áreas úmidas. Dessa forma, as diferentes classes de uso do solo mapeadas, aliadas a identificação de APP, foram enquadradas em diferentes classes de adequabilidade frente à instalação de empreendimentos logísticos. Os resultados encontrados apontam para o cenário em que cerca de 11% da área apresenta adequabilidade satisfatória, enquanto que 76% restrição ao uso. Do exposto, com o mapeamento da área de estudo foi possível indicar áreas aptas ao recebimento de empreendimentos, contribuindo, assim, para uma melhor qualidade ambiental do trecho avaliado.
GOVERNANÇA DAS ÁGUAS E INDICADORES DE PRESSÃO-ESTADO-IMPACTO-RESPOSTA NA BACIA HIDROGRÁFICA DO RIO TRACUATEUA (PARÁ-BRASIL)
Authors: Silva Dhne Maria Pereira da , De Lima Aline Maria Meiguins , Pontes Altem Nascimento , Imbiriba Breno Cesar de Oliveira
Published: February 2021

A Amazônia Oriental é formada por bacias hidrográficas de comportamento fluvial e flúvio-marinho, característico do Nordeste do estado do Pará. Um exemplo é a bacia do rio Tracuateua, que apresenta todos os indicadores do processo de uso e ocupação da terra típicos desse ambiente. Para a compreensão dessa dinâmica, foram avaliados os aspectos de Governança das águas na bacia do rio Tracuateua, com base no levantamento de indicadores locais e no diagnóstico Pressão-Estado-Impacto-Resposta (PEIR). Foram investigados os usuários residenciais, agricultores e criadores de animais; e adotadas as informações secundárias de saneamento e consumo de água fornecidas pelos órgãos estaduais e federais, que foram analisadas segundo métodos de agrupamento, permitindo identificar os principais fatores de Pressão, Estado e Impacto atuantes e os de Resposta aplicados. Os resultados obtidos indicaram que os fatores de Pressão são atuantes (intensificação da alteração da cobertura da terra e saneamento ambiental inadequado), porém os Impactos gerados precisam ser melhor quantificados. Existe a necessidade de melhorar a coleta de dados ao longo do tempo, a qualidade e quantidade das águas; a definição adequada do total consumido pelo setor produtivo; as demandas ecológicas de água; a melhor caracterização dos usos múltiplos; e o fortalecimento institucional, com a integração Estado-Município e execução dos Planos já existentes que objetivam o ordenamento territorial. Todos esses fatores são essenciais para a Governança das águas e eficiência do processo de gestão e regulação.
Analysis of the Influence of Different Construction Joints on the Ductility of Cast-in-Place Frame Structure
Authors: Yan Xi Kang , Zhang Bei , Zhao Guo Liang , Zhang Shun
Published: February 2021

This article through to the two common cast-in-situ frame structure (casting of a whole, with a construction joint) and 6 root not construction joints under axial pressure ratio through concrete columns of different processing low reversed cyclic loading experiment, study their experimental phenomena, hysteresis curves, displacement ductility, stiffness degradation, thus draw the conclusion: 1, the existence of the construction joint can lead to the decline of ductility of frame structure. 2. When the test axial pressure is relatively low, the presence or absence of construction joints and different treatment methods will obviously affect the ductility of the cast-in-place frame structure. 3. When the test axial pressure is relatively high, the presence or absence of construction joints and different treatment methods will not have a significant impact on the ductility of the cast-in-place frame structure.
Crack Growth Evaluation of Induction Quenched JIS-S45C Steel Based on Stress Intensity Factor Simulation
Authors: Matsueda Takahiro , Tamura Ayumu , Mizobe Koshiro , Kida Katsuyuki
Published: February 2021

Problems lived with fatigue fracture for the safe design of the members and structures. In this study, rotating bending tests were performed to investigate the fatigue crack propagation behavior of induction quenched and tempered JIS S45C low carbon steel. Hardness distribution was checked by the Vickers hardness test machine and the microstructure in cross section and fracture surface were observed with an optical microscope and a scanning electron microscope. The depth of the hardened boundary was approximately 1 mm from the surface and formation into martensite occurred at the surface of the specimen. It was ascertained that fracture surface of notched specimens consisted of the five fracture types. In addition, the maximum stress intensity factor of fatigue cracks increased during rotating bending test on notched specimen. The relation between SIF and the fracture surface is discussed.
Contact Temperature Calibration of PPS Thrust Bearings under Dry Condition
Authors: Nihon’yanagi Hiroya , Matsueda Takahiro , Kida Katsuyuki , Kashima Yuji
Published: February 2021

In the present study, Rolling Contact Fatigue (RCF) tests of Poly-phenylene-sulfide (PPS) thrust bearings under dry condition were carried out and the relationship between fatigue life of bearings and temperature was studied. Furthermore, in order to investigate maximum temperature of PPS thrust bearings in service, in order to obtain the calibration data, the temperatures of rolling contact element and Infrared (IR) temperature on the side of top race were measured and correlated. It is concluded that the contact temperature of failure PPS bearing was higher than the glass transition point but lower than a melting point of PPS.
Computational Analysis of Laser Cladding of Preset MCrAlY Coating Based on ANSYS Ii-Stress Field
Authors: Wang Dong Sheng , Yang Ke Jian , Yang Hao , Zhang Pei Pei
Published: February 2021

A finite element model of thermal coupling stress field during laser cladding plasma spraying of preset MCrAlY coating was constructed based on the finite element model of temperature field by using the indirect thermal coupling method in ANSYS finite element software. Moreover, stress field during laser cladding was analyzed. Through the constructed model, variation laws of stress field with time during laser cladding and cooling process could be mastered. Based on the stress field, the formation mechanism of cracks in laser cladding coating and influencing factors were further analyzed and some solutions to cracks of laser cladding coating were proposed.
Effects of Heat Accumulation on Temperature Field during Multi-Track Laser Cladding of Preset MCrAlY Coating
Authors: Wang Dong Sheng , Yang Hao , Yue Li Ye , Zhang Pei Pei
Published: February 2021

To investigate influences of multi-track overlapping on melting of preset MCrAlY coating during laser cladding plasma spraying, a three-dimensional finite element model of the continuously moving temperature field during multi-track laser cladding was constructed using the ANSYS parametric design language (APDL) based on the existing temperature field model during single-track laser cladding. According to analysis results of temperature field, temperature of samples increases gradually during laser cladding due to heat accumulation effect of laser scanning, and the molten pool expands gradually. There are evident differences among different scanning pathways. Therefore, it is impossible to get high-quality cladding coating with uniform melting and small dilution ratio. Molten pools with basically same sizes in different scanning pathways can be gained by decreasing laser power or increasing scanning speed in different tracks one by one. Similarly, differences of molten pools in different scanning pathways can be relieved effectively through preheating of samples. Through a closed-loop control over the highest cladding temperature, a more even cladding coating can be gained through adaptive control of laser power and / or scanning speed.
Modelling Material Parameters of Selected Composite Structures of Tires
Authors: Stodola Jiří , Breznická Alena , Stodola Petr , Furch Jan
Published: February 2021

The paper presents selected results of experimental and computational modelling of composite material samples of tires with cord ply (casing) and breaker textile reinforcement. The computational modelling included applications of finite element methods. The output is to determine and verify the influence of material parameters of textile reinforcement. The results were confirmed by the experiment and computational modelling verification. For elastomeric matrices hyperelastic behavioural patterns of this material were considered.
Property Evaluation of FML (Glare)
Authors: Bhat Sunil , Adarsha H. , Ravinarayan V. , Prasad Kaushik V.
Published: February 2021

Fiber metal laminate (Glare) made of 2014-T6 aerospace aluminum alloy sheets adhesively bonded with E-glass fiber based composite prepregs is investigated in the paper. The fabrication procedure of the laminate is explained. Chemical composition, macrostructure and residual stress of aluminum alloy are obtained. Mechanical properties of the laminate viz. tensile, flexural and shear strengths are measured.
Study on the Effect of Different Template Agents on the Synthesis of MCM-48 Molecular Sieves
Authors: Li Xin Xin , Li Mei , Dong Liu Yi , Su Kai Min , He Yun , Lin Qing
Published: February 2021

At present, most of molecular sieves (MCM-48) are prepared by using dual template agents. In this paper, the effect of different template agents on the synthesis of MCM-48 under the same conditions is studied. MCM-48 was synthesized by different combinations of templates (CTAB + TEAOH, CTAB + TBAB, CTAB + P123). The specific surface areas of them were compared under different crystallization temperature and different crystallization time. The results show that the specific surface area of MCM-48 prepared by CTAB + TEAOH is higher than that of other dual template agnets at the same crystallization time and temperature when the molar ratio of CTAB to another template is 9.
Antibacterial Properties of Silver Nanoparticles Synthesized Using Piper betle L. Leaf Extract
Authors: Vu Tien Hieu , Bui Van Huan , Nguyen Ngoc Thang
Published: February 2021

The green synthesis of silver nanoparticles (AgNPs) using herbal plants has gained much attention due to their potential widespread applications, especially in biomedical application to control pathogenic microbes. The aim of our study was to evaluate the antibacterial properties of synthesized AgNPs using aqueous leaf extract of Piper betle L., an important medicinal plant. The AgNPs were identified by UV-Visible spectrometry (UV-Vis), X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectrometry (FT-IR). The presence of surface plasmon band around 420-460 nm indicated AgNPs formation. Spherical nature, unique size-distribution and crystal structure of the AgNPs with diameter around 10-20 nm were affirmed by TEM and XRD analyses. The FTIR measurements showed the presence of bioactive compounds in the extract responsible for the efficient reduction of silver ions and stabilization of the AgNPs. The results from the antimicrobial assays suggested that the biosynthesized AgNPs were potent against pathogenic bacteria including Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus.
Influence of some Chemical Elements on SDAS of A357 Alloy
Authors: Pan Jie Hua , He Ke Zhun , Wang Meng , Zeng Jian Min
Published: February 2021

A solidification model of coarsening coefficient for the criterion of secondary dendrite arm spacing has been established in this paper. When the model is applied to aluminum cast alloy, it is found that the model is in good agreement with the experiment results. Experiments and analysis show that addition of some chemical elements is conducive to the refinement of the secondary dendrite arm spacing under the same solidification condition. Different chemical elements have different refining effects, and Zr and Ti have better refining effect on A357 aluminum cast alloy than Cu.
Investigation Toiler Weld Blank of SSM 2024 Aluminum Alloys by Friction Stir Welding Joint
Authors: Dunyakul Yongyuth , Meengam Chaiyoot , Maunkhaw Dech
Published: February 2021

The objective of this research was to investigate variables that affected the adhesion of the welded joints for TWBs with FSW in the SSM 2024 aluminum alloys. The results clearly showed that there was a good adhesion of the samples in every experiment. Longitudinal voids can also been found on the top surface of some variables. The average size of cross-links structure of Al2Cu phase (β phase) in SZ, broken into smaller pieces, was around 4 to 7 μm and evenly mixed with alpha phase (α phase). The effect of fracture of Al2Cu phase promoting better mechanical properties. The appropriate tensile strength from the experiment came from variables at the work angle at 15o, rotation speed at 2720 rpm, and welding speed 60 mm/min which provided maximum tensile strength value at 205.0 MPa and the maximum average hardness at 132.4 HV, higher than the weld region. The assessment results showed that the differences in welding variables resulted in different mechanical properties.
Effect of Scanning Interval on Polishing Effect of S136D Die Steel
Authors: Zhou Hao , Zhao Zhen Yu , Zhou Hou Ming , Li Kai , Jin Jing Cheng
Published: February 2021

Laser polishing technology plays an increasingly important role in the material processing technology.In order to study the influence of scanning interval on the polishing effect of S136D die steel, the single factor experiment method is used in this paper. The continuous fiber laser is used to carry out many laser polishing experiments and the influence of laser scanning interval on the surface morphology of S136D die steel is analyzed.The results show that the surface roughness of polished samples decreases first and then increases with the of scanning interval. When the scanning interval is in the range of 0.03-0.1mm, the surface roughness of samples is relatively flat, and the lowest surface roughness can be reduced to 0.781μm, and the reduction rate of surface roughness can reach 90.2%.
Effect of Dressing Parameters on Material Removal Rate when Surface Grinding SKD11 Tool Steel
Authors: Tran Thi Hong , Bui Thanh Danh , Tuan Nguyen Anh , Tuyen Vu Trung , Tung Luu Anh , Nguyen Thanh Tu , Giang Tran Ngoc , Pi Vu Ngoc
Published: February 2021

Nowadays, surface grinding is one of the most common of metal finishing methods. The efficiency of this process is affected by the so-called process parameters such as dressing feed rate (S), rough dressing depth (ar), rough dressing times (nr), fine dressing depth (af), fine dressing times (nf), and non-feeding dressing (nnon). etc. In this paper, the optimization of dressing parameters in surface grinding SKD11 tool steel is studied. The aim of the study is to find the most appropriate value set of dressing parameters to maximize the material removal rate (MRR). In order to solve the problem, the Taguchi method is used. Based on an orthogonal array L16(44x22), sixteen experiments have been conducted. By analyzing the experimental results, an optimal solution of such optimization problem has been solved, presenting the most appropriate dressing parameters as follows: ar = 0.015 mm, nr = 2 times, af = 0.005 mm, nf = 0 times, nnon = 0 times, S = 1.6 m/min. The discovered technology mode has been applied to the real machining process and the outcome shows out a much better result in comparison with default setting modes, that the difference between the model values and the real values of the roughness average is controlled within 3.87% of the ranges.
Influence of Dressing Conditions on Surface Roughness when Surface Grinding SKD11 Steel
Authors: Tran Thi Hong , Bui Thanh Danh , Ly Hoang Tu , Ngo Ngoc Vu , Nguyen Thanh Tu , Giang Tran Ngoc , Pi Vu Ngoc , Tung Luu Anh
Published: February 2021

This paper presents an optimization of dressing conditions for SKD-11 steel grinding using HaiDuong grinding wheel made in Vietnam. Taguchi method was used to design experiment and calculate the optimized dressing conditions. Effects of the six input parameters including feed rate (S), depth of rough dressing cut (aedr), rough dressing times (nr), depth of finish dressing cut (aedf), finish dressing times (nf) and non-feeding dressing (nnon) with 4 levels on the machined surface roughness were investigated for optimization process. To find out the influence degree of each input parameter on output results, S/N ratio was analysized. Experimental results show that the average surface roughness after 3 times of the repeated experiments was 0.208 μm and deviation was 11.23% comparing with the predicted values.
Study on Linear Segregation of ZL205A Alloy
Authors: Hu Wu , Zhu Ke , Wang Meng , Huang Wei Dong , Zeng Jian Min
Published: February 2021

Linear segregation of high strength aluminum alloy ZL205A castings were studied by X-ray Nondestructive testing, scanning electron microscope and energy dispersive spectrometer. It is found that the linear segregation occurs at the large wall thickness of the casting and/or at the place where the wall thickness is in transition. Segregation element is mainly Cu, which exists as compound θ (Al2Cu) phase. The formation of linear segregation is related to the flow of Cu-rich melt in the late solidification period, while the occurrence of thermal cracks promotes the formation of linear segregation. The formation of linear segregation of the casting can be effectively prevented by eliminating hot spots of the casting, refining crystal grains and increasing solidification speed of the casting.
Optimizing Dressing Conditions for Minimum Flatness Tolerance when Grinding SKD11 Tool Steel
Authors: Tran Thi Hong , Giang Tran Ngoc , Ngo Ngoc Vu , Bui Thanh Danh , Nguyen Thanh Tu , Nguyen Thi Quoc Dung , Pi Vu Ngoc , Tung Luu Anh
Published: February 2021

This study is to determine effects of the dressing parameters to the flatness tolerance (Fl) when grinding SKD11 steel using HaiDuong grinding wheel and also propose the suitable dressing parameters to obtain the smallest flatness tolerance. In this paper, the effects of the six input parameters including feed rate (S), depth of rough dressing cut (ar), rough dressing times (nr), depth of finish dressing cut (af), finish dressing times (nf) and non-feeding dressing (nnon) to the flatness tolerance were investigated. To find out the influence of each input parameter on output results, the S/N ratio was analysized. Evaluated experimental results show that, the average flatness tolerance was 4.05μm and deviation of this value was 11.38% compared with the predicted value.
Experimental Study on the Influence of Second-Order Effect on Shear Bearing Capacity of Frame Columns with Cracks under Different Axial Compression Ratios
Authors: Yan Xi Kang , Zhang Shun , Zhao Guo Liang , Chen Xiao , Zhang Bei
Published: February 2021

The construction joint is the weak part of the structure, and the P-δ effect is mostly ignored when considering the second-order effect, so it is necessary to study the influence of second-order effect on frame columns. Based on the above considerations, under different axial compression ratios, the mechanical properties of the construction joints of the frame columns with construction joints and the cast-in-situ frame columns were studied by low cycle repeated load testsand analyzed the influence of the second-order effect on the shear capacity of frame columns with joints. The test results indicate that the existence of construction joints reduces the shear-bearing capacity of the specimens, and the second-order effect has a greater impact on the columns with joints under the same axial compression ratio, and the shear capacity decreases more. With the increase of the axial compression ratio, the second-order effect will be weakened on the frame column with seam, but when the axial compression ratio exceeds a certain limit, the second-order effect will be increased.
Alternative Approaches to Mentoring
Authors: Dirks Joni L.
Published: February 2021

Topic

Various approaches facilitate mentoring for critical care nurses.

Clinical Relevance

Mentoring is an important strategy to help recruit, retain, and develop nurses with critical care expertise. Mentoring benefits nurses at all career stages, from novice to expert. Effective mentoring programs benefit not only mentors and mentees but also organizations and patients by ensuring adequate numbers of nurses with critical care knowledge and skills.

Purpose

Mentoring programs require careful planning to ensure that the objectives of the program align with the needs of the target audience, and that adequate resources are available to support the mentor-mentee relationship. This article identifies opportunities for mentoring in critical care nursing and provides recommendations from the literature for developing an effective program.

Content Covered

Various objectives for mentoring programs are described, including supporting retention, providing clinical development, and planning succession. Program logistics are explored, such as selecting mentors, matching mentors with mentees, setting goals and expectations, and evaluating the program. In addition, the article identifies strategies for overcoming common barriers to mentoring, which include a lack of time and poor access to qualified mentors.
C-Type Lectin Maintains the Homeostasis of Intestinal Microbiota and Mediates Biofilm Formation by Intestinal Bacteria in Shrimp
Authors: Zhang Yu-Xuan , Zhang Ming-Lu , Wang Xian-Wei
Published: February 2021

Intestinal microbiota are closely related to host physiology. Over the long course of evolution and interaction, both commensal bacteria and their host have evolved multiple strategies to adapt to each other. However, in invertebrates, the regulatory mechanism of intestinal microbiota homeostasis is largely unknown. In the current study, a digestive tract–specific C-type lectin, designated as CTL33, was identified because of its abundance and response to bacteria in the intestine of kuruma shrimp (Marsupenaeus japonicus). Silencing of CTL33 expression led directly to intestinal dysbiosis, tissue damage, and shrimp death. CTL33 could facilitate biofilm formation by the intestinal bacteria. This function originated from its unique architecture, with a lectin domain responsible for bacteria recognition and a coiled coil region that mediated CTL33 dimerization and cross-linked the bacteria into a biofilm-like complex. By mediating the formation of a biofilm, CTL33 promoted the establishment of intestinal bacteria in intestine and maintained the homeostasis of the microbiota. Thus, to our knowledge, we demonstrated a new mechanism of C-type lectin–mediated biofilm formation by intestinal bacteria, providing new insights into intestinal homeostasis regulation in invertebrates.