bluuebunny/crossref_metadata_2025 huggingface dataset:
Integration of TAM, TPB, and Self-Image to Study Online Purchase Intentions in an Emerging Economy
Authors: Singh Devinder Pal
Published: June 2017

E-commerce offers significant opportunity for retailers in emerging markets like India due to the growing Internet popularity and rising incomes. But the Internet penetration growth does not commensurate with the online retail sales. This necessitates unraveling and understanding the online buying behavior. This paper employs ‘Theory of planned behavior (TPB)', ‘Technology acceptance model (TAM)' and self-image to unfold the online consumer behavior. It proffers an integrated model of online consumer behavior by integrating the self-image variable with the TPB and TAM models. The study tests the various components of integrated model and find that attitudes, subjective norms, self-image, and self-efficacy significantly impact online purchase intentions. The study makes significant theoretical contributions and provides valuable insights into the consumers' online purchase behavior.
Mobile Commerce Adoption
Authors: AlFahl Husam
Published: June 2017

Mobile commerce can be a great potential to generate new streams of revenue for many established and new businesses. The penetration rates for mobile phone subscriptions in many countries show that there are significant opportunities to invest in and introduce mobile commerce services in many of these markets. The aim of this research is to explore and identify the various factors that influence the intention to adopt mobile commerce in Saudi banks and telecoms. A number of these factors were included in this research as they are chosen from well-known theories and investigated in the current study within the mobile commerce context using principal component analysis technique. Based on the findings of the research, the mobile commerce organizational adoption model is proposed to support organizations in order to launch mobile commerce services into the market. The findings of the research show that seven components can affect the intention to adopt mobile commerce in Saudi banks and telecoms. The three most significant components that can affect the intention to adopt mobile commerce services in Saudi banks and telecoms are performance expectancy, organizational readiness, and mobile commerce features and opportunities. The results of this research propose seven hypotheses to be tested in the future by researchers from different countries.
Perceived Mobile Information Security and Adoption of Mobile Payment Services in China
Authors: Gao Fei , Rau Pei-Luen Patrick , Zhang Yubo
Published: June 2017

The rapid deployment of mobile devices and the development of mobile services and applications require to address the mobile information security from the human side. This study was aimed at identifying factors influencing people's perception of mobile information security, to investigate the impact of these factors and to facilitate related service design. A survey was conducted and analyzed with exploratory factor analysis. Five factors were identified, including perceived familiarity, perceived impact, perceived controllability, perceived awareness and perceived possibility. Thereinto, the impact of controllability, impact and familiarity on the adoption of mobile payment was investigated. Impact significantly affected the intention to use, but not the perceived security of payment systems. Control level significantly affected the intention to use and the perceived security. Familiarity was found to have an effect on neither the intention to use nor the perceived security. Related design implications for mobile payment systems were discussed.
China's E-Tailing Blossom
Authors: Liang Bo , Tu Yanbin , Cline Thomas , Ma Zhongyu
Published: June 2017

E-tailing has a dynamic ecosystem different from traditional retailing. To the best of our knowledge, there are few case studies scientifically grounded yet practical. Nonetheless, this is the authors' goal with this book chapter. A case study of China's e-tailing is needed because China is the largest emerging market as well as the largest e-retailing market in the world. Moreover, e-tailing provides one of the most effective ways for foreign retailers to enter China's impressive retail market. This case study will explore the underlying reasons for the success of China's e-tailing market by investigating the elements of China's e-tailing ecosystem. This study will further investigate the major players in China's e-tailing market, with a focus on the Alibaba Group, China's largest e-tailing company. This study will address Alibaba's e-tailing strategies and practices by comparing Alibaba and its major domestic and global competitors (e.g., Amazon).
“School-Cinema”
Authors: Tamburini Daniela
Published: June 2017

This chapter presents an educational and consulting path for the use of new technologies that support the improvement of learning relationships in groups (Parmigiani, 2009), the construction of knowledge (Lakkala et al., 2007; Kangas et al., 2007) and the ability to recognize and explore the experience of communication and relationship at professional and personal levels, for the individual and for groups in order to enhance abilities and professional skills on several levels: cognitive, affective, conative and practical (Paquay, Altet, Charlier, & Perrenoud, 2001). Through the report of the experiments carried out for two years and applied to two training projects for teachers of five Primary and Secondary Italian schools, the main objective is to describe and present the overall results. The approaches used were inspired by the method of participatory research and action research with a clinical and pedagogical approach. The methodology is based on the case study of the Clinica della Formazione (Massa, 1992; Franza, 2003) that increases the emotional, communicative and relationship dimensions and gives concreteness not only to the educational action but also to the process behind it, which then becomes the target of investigations.
Supporting Motion Capture Acting Through a Mixed Reality Application
Authors: Kade Daniel , Lindell Rikard , Ürey Hakan , Özcan Oğuzhan
Published: June 2017

Current and future animations seek for more human-like motions to create believable animations for computer games, animated movies and commercial spots. A technology widely used technology is motion capture to capture actors' movements which enrich digital avatars motions and emotions. However, a motion capture environment poses challenges to actors such as short preparation times and the need to highly rely on their acting and imagination skills. To support these actors, we developed a mixed reality application that allows showing digital environments while performing and being able to see the real and virtual world. We tested our prototype with 6 traditionally trained theatre and TV actors. As a result, the actors indicated that our application supported them getting into the demanded acting moods with less unrequired emotions. The acting scenario was also better understood with less need of explanation than when just discussing the scenario, as commonly done in theatre acting.
Contextual Issues in Groupware Applications for Educational Support Groups
Authors: Luna-García Huizilopoztli , Mendoza-González Ricardo , Rodríguez-Martínez Laura C. , Rodríguez-Díaz Mario A. , Lara-Cisneros Guadalupe , Ordaz-García Carlos R. , Mercado-Pérez Sandra , López-Orozco Alejandro U.
Published: June 2017

The objective of this chapter was to identify a set of contextual issues in groupware applications used by educational support groups. The analysis was performed through a Needfindings study where 20 active members of three Mexican federal educational-support groups called USAER were recruited. The analysis considered both users and functional vantage point. The participants (from one USAER) provided feedback and insights from their daily activities related to communication with others and resources access helping to define and understand users' scenarios. This information was classified and distilled as design ideas in low fidelity prototypes constructed by participants themselves under guidance from authors. Finally, prototypes were evaluated by the members of the other two USAER group providing their perception as expert users. The study derived in a set of particular contextual issues that directly influence interactions in group applications. These findings could be take into account by designers as a reliable starting point for well-designed User Interfaces for groupware.
Indian Higher Education
Authors: Bhagwat Nikhila Deep , Rajguru Hemant
Published: June 2017

This chapter gives an overview of Indian Higher Education system with special reference to Open and Distance Learning. It enlists the merits and limitations of Open and Distance Learning system. It also focuses on complexities and weaknesses of Indian Higher Education comparing it with the educational policies in other Asian Countries. The chapter describes the limitations of Higher Education System in India and discusses the reforms and restructuring announced by the ministry of education in India. It further unfolds the success story of Yashwantrao Chavan Maharashtra Open University's ‘School of Agricultural Sciences' by explaining in detail the innovative practices in Agricultural ODL.
Role of Open and Distance Learning in Agriculture Education in India
Authors: Salooja Mohinder Kumar , P. Vijayakumar
Published: June 2017

The Open and Distance Learning (ODL) can be an effective and cost effective tool to reach the masses in imparting the required skills and technical proficiency. The conventional Agricultural education system has not utilized the potential of ODL in a big way for extending the reach of agriculture education and capacity building activities. Some of the challenges in ODL system include: identifying the right type and level of programme, selecting the appropriate pedagogy model, covering of large and diverse clientele group, popularization and recognition of the programmes and linkages with the industry. For successful implementation of the ODL programmes in agriculture, the interventions proposed are synergy between ODL and conventional system to improve GER and bridge the gap between demand and supply, collaboration with different institutions and industry for development and delivery of the programmes, linkage with the government schemes, popularization and recognition of ODL programmes, utilization of modern technologies, etc.
Emerging Trends in Skill-Based Education With MLearning and ERP
Authors: Killedar Manoj Shantikumar , Kamlaskar Chetana Hemant
Published: June 2017

Today there is a gap between marketable skills of the majority of workforce and the expectations of their roles. Many undergraduates have difficulties when moving from education to employment as there is no convergence between acquired education and required skill sets. Indian Government has recently introduced one of the national policies such as NSQF for developing link between education, skills and aptitude. YCMOU intends to impart skill education using the ‘Learn and Earn' approach. This chapter present all implementation details of technologically driven changes to impart ‘Industrial and Business skills' effectively. A diploma programme offers flexible teaching-learning environments aiming to offer adequate online and offline tools for delivery of information, interaction and collaboration. It also offers ‘On-Job Training (OJT)' to provide an opportunity for the learners to work in real environment. A mandatory OJT is aiming for grooming of appropriate skills. A novel feature of this diploma programme is the use of self and peer assessment processes which encourages learning.
From Network Builders to Knowledge Clusters
Authors: Garcia Blanca C.
Published: June 2017

This chapter aims to explore the central notions of the Knowledge-City paradigm in which complex cluster concepts provide a perspective of the interdependencies between the many and diverse dimensions of urban value-based categories that co-exist in the northern city-region of Monterrey, Mexico, in the Mexico-Texas Borderland. The chapter succeeds to advance and further contribute to the development of the knowledge-based urban development (KBUD) paradigm by showing a hierarchical framework of knowledge units from the individual Urban Citizen-Entrepreneur to Cluster Partnerships from a Knowledge City-Region perspective. It attempts to describe their spatial footprint, their activities, and their socio-economic impacts. Then, based on a case study in the Mexico-Texas borderland, it is advanced that a multi-variable framework holds promise for the analysis of knowledge-based development initiatives and possibly for future developing regions at a global scale.
Urbanization and Electric Power Crisis in Ghana
Authors: Cobbinah Patrick Brandful , Adams Ellis Adjei
Published: June 2017

Traditionally, urbanization is hailed as an important force for socio-economic development of countries. In fact, recent research on Africa suggests that urbanization has the potential to stimulate socio-economic development. Yet, many African countries experiencing rapid urban growth continue to bear a disproportionate amount of the costs associated with urbanization (e.g., increased urban poverty, and energy crisis among others). This is in sharp contradiction to the popular notion that urbanization is a stimulus for socio-economic development. Using Ghana as a case study, this chapter discusses the extent to which rapid urbanization influences power supply and the implications on socio-economic development. The chapter focuses on four issues: (1) the history of power and urbanization in Ghana; (2) the influence of urbanization on power crisis in Ghana; (3) the socio-economic implications of urbanization-induced power crisis; and (4) the policies available in addressing the power crisis. Recommendations to address the ever-growing demand for electrical power are proffered
A Temporal Case Study of Green Business Initiatives of a Leading Firm in the Indian Hydrocarbon Industry
Authors: Chakraborty Kamalika , Verma Nishant K.
Published: June 2017

The effective functioning of modern business in the current day and age is incomplete without taking into consideration its extended impact on society and environment. In this respect companies need to continuously revisit and analyse their green initiatives to keep them relevant and contribute positively to the global cause. This book chapter provides a capable framework for organizations to conduct temporal analysis of their green initiatives and enable them to reflect on their current positions and strategize their future course of actions. Further, we analyse the green initiatives of the Indian Hydrocarbon Industry leader: Indian Oil Corporation Limited (IOCL) and trace its green journey across defined time periods thereby depicting the use of the developed framework in addressing the gap of temporal analysis in the literature.
A Case of Kumbh Mela at Allahabad
Authors: Anand Sandip
Published: June 2017

Management of mega events like Kumbh Mela, rests on the involvement of communities and local authorities who have rich learning heritage with them. Using Kumbh Mela as a case, this chapter highlights the role of various factors which are important for urban pace management. Understanding of the market at Kumbh Mela offers insights related to the BoP market. The chapter has following key inquiries: a) What kind of space was the Magh/Kumbh Mela? What kind of economic activities happened? b) What was the value system? c) What were the things being communicated? What were the things being remembered by them? This chapter uses exploratory research methodologies. Towards the end of the chapter, findings and its implications have been discussed.
Sustainable Value Enhancement in Closed Loop Supply Networks
Authors: Paul Arun Kumar
Published: June 2017

Closed-loop supply chains (CLSC) deal with integrating product returns into the total supply chain over the lifecycle of the product, thereby recovering a maximum amount of value. In this chapter, the CLSC is studied through quantitative models at three levels. The study at the first level analyses a generic closed loop strategic framework under various scenarios, capturing the implementation maturity of CLSC. In the second level, a quantitative model for multi stage integrated forward and reverse logistics network is analyzed. Finally in the third level of study, a microscopic view is taken in which a joint economic order quantity (EOQ) and economic production quantity (EPQ) model is studied to optimize value by using proper mix of newly purchased components /products with recycled components /products. The final control parameters may be utilized by policy makers, CLSC network designers or practicing managers for effective decision making and coordination.
Strategic Planning, Cultural Context, and Business Continuity Management
Authors: Perano Mirko , Hysa Xhimi , Calabrese Mario
Published: June 2017

This study is focused on the role, importance and practice of Business Continuity Management (BCM) in relation with Strategic Planning (SP) and Cultural Context (CC) by offering a holistic framework for short-term and long-term strategic business analysis. The purpose is to create a unique structured plan for understanding the organizational failure willingness and to create a culture of readiness, feedback and risk management. The methodology used is quantitative with questionnaire for collection data. The study sample includes 50 organizations from four different sectors: banking, services, industrial and insurance in Shkoder (Albania). The research findings show a positive correlation between SP and BCM (0.54%), with a significant positive impact of SP on BCM. A positive correlation is founded between SP and CC (0.588%). The study suggests that placing the BCM in the Corporate Culture may be entitled as another manner of integrating BCM and SP in one structure. Between culture and strategy there is a huge number of characteristics and similarities they have in common with each other.
Determining Influencing Factors of Currency Exchange Rate for Decision Making in Global Economy Using MARS Method
Authors: Dinçer Hasan , Hacıoğlu Ümit , Yüksel Serhat
Published: June 2017

The aim of this study is to identify the determinants of US Dollar/Turkish Lira currency exchange rate for strategic decision making in the global economy. Within this scope, quarterly data for the period between 1988:1 and 2016:2 was used in this study. In addition to this aspect, 10 explanatory variables were considered in order to determine the leading indicators of US Dollar/Turkish Lira currency exchange rate. Moreover, Multivariate Adaptive Regression Splines (MARS) method was used so as to achieve this objective. According to the results of this analysis, it was defined that two different variables affect this exchange rate in Turkey. First of all, it was identified that there is a negative relationship between current account balance and the value of US Dollar/Turkish Lira currency exchange rate. This result shows that in case of current account deficit problem, Turkish Lira experiences depreciation. Furthermore, it was also concluded that when there is an economic growth in Turkey, Turkish Lira increases in comparison with US Dollar. While taking into the consideration of these results, it could be generalized that emerging economies such as Turkey have to decrease current account deficit and investors should focus on higher economic growth in order to prevent the depreciation of the money in the strategic investment decision.
Managing Real-Time Information Within BIM-Based Processes for Assessing Building Behaviours in Operation
Authors: Pasini Daniela , Ciribini Angelo Luigi Camillo , Daniotti Bruno
Published: June 2017

Considering the remarkable shift that the digitalisation is nowadays bringing about in the building sector, the paper focuses on how the great amount of data collected around assets is changing the way buildings are operated, particularly for what concerns innovation on products, processes and technologies. By establishing a connection between as-designed virtual models and as-delivered physical assets, the paper presents methods and tools based on information management and developed for assessing building behaviours in operation and for defining control strategies for satisfying user needs. The research aims to investigate how the building process could benefit from the availability of multi-faceted information collected in real time (e.g. through sensors) during the operational stages of buildings. Digitally-enabled practices and technologies have been developed and tested for improving a data-driven asset management, by enriching Building Information Models through data gathered through Building Management Systems, according to the Industry Foundation Classes schema.
Foreign Circular Element Detection in Chest X-Rays for Effective Automated Pulmonary Abnormality Screening
Authors: Zohora Fatema Tuz , Santosh K.C.
Published: June 2017

In automated chest X-ray screening (to detect pulmonary abnormality: Tuberculosis (TB), for instance), the presence of foreign element such as buttons and medical devices hinders its performance. In this paper, using digital chest radiographs, the authors present a new technique to detect circular foreign element, within the lung regions. They first compute edge map by using several different edge detection algorithms, which is followed by morphological operations for potential candidate selection. These candidates are then confirmed by using circular Hough transform (CHT). In their test, the authors have achieved precision, recall, and F1 score of 96%, 90%, and 92%, respectively with lung segmentation. Compared to state-of-the-art work, their technique excels performance in terms of both detection accuracy and computational time.
Diferenças de conhecimento prévio e processos de estudo: interaçoes entre nível de expertise e aprendizagem
Authors: Rosa Gustavo Danicki Aureliano , Galvão Afonso Celso Tanus
Published: June 2017

Esta pesquisa qualitativa e exploratória investigou como conhecimentos prévios influenciaram processos de estudo a partir da análise da atividade de estudo de indivíduos com material de domínio e não domínio. Participaram da pesquisa seis indivíduos que leram dois textos, de domínio e não domínio, com orientação para o estudo dos materiais. Após o estudo de cada texto, os participantes eram questionados sobre os processos de estudo. Os resultados sugerem que o conhecimento prévio consolidado influi sobre o processo de estudo, afetando o reconhecimento de informações, a velocidade de estudo, a capacidade de articulação metacognitiva dos indivíduos e a postura perante o processo de ensino, considerando necessidades de suporte informacional para a sustentação do processo de estudo e a forma do apoio em situação de ensino. Os resultados apontam a importância da ação docente para o incremento de oportunidades de aprendizagem, o que implica no desenvolvimento aperfeiçoado e competente de processos de avaliação da aprendizagem, sobretudo as de fundo diagnóstico.
Effect of Annealing Treatment on the Mechanical Properties of Cu-Ni-Si/Al-Mg-Si Clad Composite Wires
Authors: Yang Zhen , Mi Xun Jun , Xie Hao Feng , Peng Lijun
Published: June 2017

Copper-clad aluminum (CCA) composite wires have been widely used in cable industry. Especially for the application in aerospace, the light weight character of wires is particularly important. To improve the mechanical properties of wires, Cu-Ni-Si alloy and Al-Mg-Si alloy are employed to replace pure copper and pure aluminum, respectively. The objective of this work is to find the appropriate annealing treatment conditions to produce the Cu-Ni-Si/Al-Mg-Si clad composite wires with optimal combination properties. The wires were fabricated by a drawing process and heat treatment at different temperatures and times. Mechanical and electrical properties dependent on outer Cu-Ni-Si, internal Al-Mg-Si and interface properties, are characterized and analyzed. The fracture behavior of Cu-Ni-Si/Al-Mg-Si clad composite wires was studied together with the stress-strain curves of the composite wires.
Thermodynamic Calculation of the Rare Earth Permanent Magnets: Fe-RE (RE=Ho, Er, Tm, Sm) Binary Systems
Authors: Rong M.H. , Chen X.L. , Wang Jiang , Lin S.D. , Rao G.H. , Zhou H.Y.
Published: June 2017

The experimental data of phase equilibria and thermodynamic properties of the Fe-RE (RE=Ho, Er, Tm, Sm) binary systems were reviewed. The previous thermodynamic calculation of the Fe-RE (RE=Ho, Er, Tm, Sm) binary systems were discussed based on the comparison of the calculated phase diagram and thermodynamic properties with the experimental data. The compared results show that more experimental information of phase diagram and thermodynamic properties in the Fe-RE (RE=Ho, Er, Tm, Sm) binary systems should be determined and then thermodynamic re-calculation of these binary systems would be performed to develop compatible and available thermodynamic database of the RE-Fe-B ternary systems. It is indispensable to study the relations between alloy compositions, microstructure and magnetic properties of novel Nd-Fe-B-based permanent magnets.
Application of State of the Art Assessment for Pipeline Girth Weld
Authors: Yao Deng Zun , Li Zhi Wen , Liu Jian Wu , Chen Lin
Published: June 2017

In the pipeline construction, the girth welds tend to be the weakness because of defects and microstructural heterogeneities. The importance of suitable assessment of various defects in the weld is not only to prevent the cracks from unstable growth to cause catastrophic accident but also can effectively reduce the weld repair to reduce construction cost. Although many welding defects assessment methods and codes have been applied in this field, there are many differences among them. In this paper, the application of weld defect assessment methods was extensively studied. The key points of ECA applications, such as the pipeline axial stress and toughness, have been introduced. Furthermore, some suggestions were given on the application of girth weld ECA assessment.
Failure Analysis of Dissimilar Steel Weld Cracking on High and Medium Pressure Guide Pipe
Authors: Zhang Xin , Chen An Sheng , Wang Xiao Ru , Wang Jia Qing , Ni Man Sheng , Shi Yang
Published: June 2017

The hardness test and microstructure characterization were adopted to analyze the cracking failure of dissimilar steel weld cracking on high and medium pressure steam lead pipe. The materials of the cylinder, the guide pipe and the welding material were ZG15Cr2Mo1, 1Cr9Mo1VNbN and AWS 5. 11 ENiCrFe-1, respectively. The study showed that the hardness of the fusion line was higher than that of the adjacent base metal (ZG15Cr2Mo1) and nickel base welding, which was the weak area. The pressure pipe cracking is high temperature fatigue crack. The grains in the weld joint region were coarse, indicating that the welding specification is too broad and the time for welding remaining in the sensitized temperature zone is too long. The improper welding process was the main reason for the welding cracking of the high and medium pressure guide pipe.
Microstructure Evolution of the Mg-3Zn-0.5Er Alloy during Hot Rolling
Authors: Liu Jin Xue , Liu Ke , Li Shu Bo , Wang Zhao Hui , Du Wen Bo
Published: June 2017

The microstructure evolution of the as-rolled Mg-3Zn-0.5Er alloy (wt.%) has been investigated. The results showed that the phase constituents of the sheet were composed of the α-Mg solid solution and the I-phase (Icosahedral quasicrystalline). The microstructure of sheets transformed from the deformation twinning into dynamic recrystallization (DRX) grains. Furthermore, the deformation twinning appeared again in the dynamic recrystallization grains during further hot rolling. It indicated that the twining was the main deformation mechanism and marginal dynamic recrystallization (DRX) occurred in the deformation twins at low strains. As the reduction reached 39.6%, the twin dynamic recrystallization (TDRX) regions cluster and widen by consumption of the initial deformation twins, then formed shear bands. After the reduction exceeded 66.3%, the microstructures of sheets were composed of equiaxed DRXed grains and fine twins. Moreover, compared with the RD-ND plane, the RD-TD plane had a smaller average grain size, ultimately reached ~15.8μm, which also led to a higher average value of the hardness.
Defect Formation Mechanism and Influence of Processing Parameters on Surface Quality of Copper Clad Steel Composite Wires Prepared by Core-Cladding Continuous Casting
Authors: Wu Wei Yu , Liu Xue Feng , Yi Feng
Published: June 2017

Copper clad steel (CCS) composite wires with the carbon steel core diameter of 8 mm and copper cladding thickness of 1 mm were prepared by core-cladding continuous casting method under argon protection. The effects of melt temperature, molten metal height and drawing velocity on the surface quality were investigated. The formation mechanisms of the surface defects were discussed. The results showed that CCS wires with good surface quality could be continuously fabricated at a melt temperature of 1120 to 1200°C, a molten metal height of 2 to 4 cm and a drawing velocity of 10 to 30 mm/min. Raising the melt temperature, increasing the molten metal height or decreasing the drawing velocity is in favor of improvements in the surface quality. Insufficient supplement of liquid copper during solidification shrinkage resulted in surface dimple. Transverse hot cracking and exposed steel defect appeared because the frictional force between cladding metal and mold was larger than the tensile strength of cladding metal under high temperature.
Common Defect Analysis for Large Section Special Steel Forging
Authors: Wen Xin Li , Gao Jian Peng , La Yuan Guo
Published: June 2017

In order to Figure the common defect in large section special steel forging and find the solution, systematic study was carried out on hundreds of large section special steel forgings in a domestic famous steel mill. The steels included: low-carbon steel Q345D/E, medium-carbon steel 27SiMn, high-carbon steel GCr15SiMn, stainless steel 20Cr13. Both the amount and type of all the defect in the above steel were calculated and analyzed. The results showed that the common defects of the steel were slags, inclusions, loose (cavity) and inner cracks. The evolution of the cavity in the ingot during forging process was simulated by a numerical simulation software Deform-3D. The inner cracks in Q345D/E and 27SiMn initiated after A→F+P transformation The cracks in GCr15SiMn formed after the precipitation of net-like proeutectoid carbides. The cracks in 20Cr13 formed after the precipitation of net-like carbides. The internal cause of the cracks was relevant to composition segregation and internal stress in the forging. The external cause was connected with effect of slow cooling. Based on the above study, a set of new process was proposed and put into industrial application, with the result that the qualified ratio of flaw inspection in the above steel mill was improved from 20% to above 87%.
Floating Behavior of Entrapped Gas in Semi-Solid Metal
Authors: Lu Hong Xing , Zhu Qiang , Li Da Quan , Zhang Fan
Published: June 2017

Semi-solid die casting technology has great advantages at defects control and has been successfully used to produce high quality aluminum alloy components for several years. In this process, semi-solid metal with high apparent viscosity and low plunger velocity are used to avoid surface turbulence which is the main source of entrapped gas in conventional die casting processes. But, entrapped gas still has other sources, such as melting, pouring, surface flooding and confluence weld. Solution heat treatment is always used to strengthen semi-solid die castings. The entrapped gas leads to blister defects, which directly decreases the acceptance rate of semi-solid die castings. So, the entrapped gas is still a serious issue in semi-solid die casting process. We studied the floating behavior of entrapped gas bubble in semi-solid metal. Two floating models were established for gas bubbles with different sizes. These models were used to analyze the possibility of entrapped gas escaping from semi-solid metal in casting practice. The results showed that entrapped gas from feed billet could not escape from the semi-solid metal in the casting process of impeller, which was proved by experiment results. These results emphasized the importance of clean melt and semi-solid metal. Some advices were given at last for avoiding or removing the entrapped gas in semi-solid die casting process.
Microstructure and Properties of 1060Al/AZ31/1060Al Composite Plates Fabricated by Explosive Welding
Authors: Bao Jia Wei , Yang Su Yuan
Published: June 2017

1060Al/AZ31/1060Al composite plates were fabricated by explosive welding. The microstructure and properties of the composite plate after explosive welding were investigated. The results showed that all bonding interface had a wavy morphology. The wavelength and amplitude of the lower interface were larger than that of the upper interface. Diffusion layer occurred in both interfaces and the thickness were both approximate 4 μm. Adiabatic shear bands and twin structure were observed in AZ31. The shear bond strength of the lower interface was larger than that of the upper interface. Larger amplitude and wavelength of the waveform implied higher bonding strength.
Comparison of Microstructure and Mechanical Properties of Aluminum Components Manufactured by CMT
Authors: Zhao Y. , Xiao Jian , Chen S.J.
Published: June 2017

This paper presents an investigation on the microstructure and mechanical property of Al-alloy parts made by using additive manufacturing based on CMT (Cold Metal Transfer) welding technology. With the same 3D model and process parameters, a set of hollow cylindrical parts with 100 layers were built up using 2319, 4043, 5356 aluminum welding wires, respectively. Then their microstructure, tensile strength, and microhardness were tested and analyzed comparatively. The layer bands characteristics were obviously observed in both 2319 and 4043 parts. In the interlayer region of the 2319 parts, the segregation of alloying elements on the grain boundaries and inside the grains were significantly more than that in the fusion line region. For the microstructure of 4043 parts, the dendrites grow upward from the bottom without interruption in the fusion line region, and the continuous growth structure was maintained. There is no obviously change on the microhardness from the bottom to the top because the organization is uniform and there is no significant difference in the grain size. The ultimate strength and elongation in the horizontal direction were higher than those in the longitudinal direction, and the 5356 parts had best mechanical properties among the three materials. Ultrasonic method was also used to measure the Young's modulus of the additive manufactured parts. The Young's modulus measuring results were accordant with the results obtained by the mechanical property testing, and the error was within 3%.
Influence of Impurities on the Microstructure and Thermal Shock Resistance of YSZ Coatings
Authors: Wei Yu Dao , Yu Yue Guang , Ji Xiao Juan , Peng Hao Ran
Published: June 2017

The impact of impurities on the microstructure and thermal shock resistance of YSZ TBCs was investigated. ZrO2-7.5wt%Y2O3 (7.5YSZ) coatings of 5 spices of compositions (4 of them were doped with one type of impurity, namely, Al2O3, Fe2O3, SiO2 and TiO2, and the other was not doped) were manufactured by APS. Thermal shock tests of these TBCs were carried out at 1100 °C, and the samples were quenched in cold water in the temperature range from 20 to 25°C. The microstructure evolution and phase analysis were performed before and after the thermal shock tests by scanning electron microscope (SEM) and X-ray diffractometer (XRD). The results showed that the thermal shock lifetime of YSZ TBCs doped with impurities was obviously reduced compared to that of no-impurity TBCs. Additionally, the differences in the microstructure and phases of YSZ TBCs were ascertained and the elements distribution was tested by Energy Dispersive Spectrometer (EDS) and Energy Dispersive X-Ray Spectroscopy (EDX).
Fracture Toughness of Tungsten Carbide Reinforced Fe-Matrix Surface Composites
Authors: Zhang Xi , Zhong Li Sheng , Wang Xin , Xu Yun Hua , Wu Hong , Fu Yong Hong
Published: June 2017

Tungsten carbide (WC) reinforced Fe-matrix surface composites were prepared by in-situ synthesis between tungsten plate and graphite in grey cast iron. The microstructure, fracture toughness, and fracture of the WC layer were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and the Vickers indentation technique, respectively. The results revealed that heat treated at 1125°C for 135min in argon atmosphere the main phase was WC with a bit of α-Fe. The fracture toughness (KIC) of the WC layer calculated using the Niihara’s equation, was 5.21 MPa·m1/2. Fractographic observations revealed that cracks propagated along the grain boundary under 2 kg loads. Moreover, both the WC particles and the interface between the WC layer and the matrix had a strong bonding strength.
Thermodynamic Analysis of Ni-Al-WC System during Self-Propagating High Temperature Synthesis
Authors: Yuan Jian Jun , Liu Xin Ying , Li Dong Min , Lou Shu Mei
Published: June 2017

Ni-Al-WC ternary system during self-propagating high-temperature synthesis (SHS) was analyzed and calculated based on thermodynamic principle, and the curves of adiabatic temperature (Tad) and preheating temperature (T0) and WC content (wt.%) were drawn. The results showed that adiabatic temperature of the system decreased with the increase of WC content and the maximum of WC content was about 34 wt.% for preheating temperature of 933K. Adiabatic temperature increased with increasing preheating temperature and properly increasing preheating temperature could promote the reaction self-sustaining when WC content was excessive and adiabatic temperature was less than 1912K.
Preparation of Continuous Al2O3/Y2O3 Coating on Carbon Fiber by a Novel Aqueous Plasma Electrolysis
Authors: Zhang Yu Ping , Shen Yong Hua , Chen Wei Wei , Cheng Huan Wu , Wang Lu
Published: June 2017

A novel aqueous plasma electrolysis applied for depositing a uniform and continuous Al2O3/Y2O3 ceramic coating on each fiber within a carbon fiber bundle are reported in this study. All equally spaced tungsten wires generated plasma arc, where the plasma was overlapped, excluded and extruded each other, finally a cylindrical plasma arc zone was formed, promoting the full coverage of the coating on each fiber. The Al2O3/Y2O3 coating protected the carbon fiber from oxidation above 850oC. Similarly, the coating significantly improved the oxidation resistance of the carbon fiber with the mass loss of ~5% after isothermal oxidation in N2 atmosphere at 800°C for 30 min, compared to ~14% of bare carbon fiber. By the movement of the T300 carbon fiber bundle, 1500 m coated carbon fiber bundle with the high-quality Al2O3/Y2O3 coating deposited on each fiber was successfully realized. It is believed that the novel aqueous plasma electrolysis will find a wide range of applications in modifying the interface of the carbon fiber reinforced composites. The present investigation will also open up a new horizon for preparing a protective coating on each fiber within two/three-dimensional carbon fiber fabric.
Effect of Magnetic Orientation on the Microwave Absorption Properties for Planar-Anisotropy Ce2Fe17N3-δ Powders/Silicone Composite
Authors: Gu Xi Sheng , Tan Guo Guo , Chen Shu Wen , Man Qi Kui , Che Sheng Lei , Jiang Li Qiang , Chang Chun Tao , Wang Xin Min , Li Fa Shen , Li Run Wei
Published: June 2017

The electromagnetic parameters of magnetic unoriented and oriented Ce2Fe17N3-δ powders/Silicone composite with 15 vol% were investigated in the 0.1–18 GHz range. It was found that the initial permeability increased from 2.78 to 3.6 as well as the optimal RL reached –61.3 dB with a thickness of 1.91 mm at 9.01 GHz for the composite after orientation. The microwave absorbing properties of oriented composite were greatly enhanced resulting from the perfect impedance match condition improved by rotational magnetic orientation. This novel rotational magnetic orientation method might provide a new way to design high performance microwave absorbers.
Synthesis of Uniform Barium Ferrite Powders by Co-Precipitation Method
Authors: Chen Min , Fan Run Hua , Zhang Zi Dong , Yin Yan Sheng , Dong Li Hua
Published: June 2017

The uniform hexagonal barium ferrite powders were synthesized by co-precipitation method using metal chloride. The effects of the amount of hexadecyltrimethyl ammonium bromide (CTAB), the water bath and calcination temperature on the phase formation, microstructure and density of barium ferrites were systematically investigated. The results showed that the formation of uniform hexagonal barium ferrite powders was significantly influenced by the amount of CTAB and the water bath could lead to the larger grain size and density. The SEM demonstrated that the BaFe12O19 powders had plate-like shape with crystallite sizes varing from 150 to 200 nm. When the amount of CTAB was 0.2g/100ml and the calcination temperature was 850 °C, the barium ferrite powders were uniform which indicated that the amount of surfactant and calcination temperature were very optimum.
Dielectric Performance of (Pb1-xSrx)Nb2O6-NaNbO3 Thin Film Materials System: Substitution Effects
Authors: Tan Fei Hu , Zhao Hong Bin , Zhang Qing Meng , Wei Feng , Du Jun
Published: June 2017

(Pb1-xSrx)Nb2O6-NaNbO3 (PSNN) dielectric thin films, x changed from 0.4 to 0.6, were deposited by pulsed laser deposition (PLD) technology on p+-Si substrate. Post-annealing was performed on the dielectric thin films at 800oC in oxygen atmosphere for 10 minutes. The Sr-composition dependence of the dielectric performance in this thin film materials system was investigated. The results indicated that dielectric constant changing with Sr-composition in the PSNN thin films showed the shape of a parabola, resulting from the morphotropic phase boundary (MPB) effect caused by the existence of both orthorhombic and tetragonal tungsten bronze phases. The maximized dielectric constant of PSNN was 58 and the leakage current density was about 2.485×10-9 A·cm-2 by calculated at-1 V in 1 kHz. The breakdown field strength reached 220 kV/mm of the developed PSNN thin film system, which is promising in energy storage systems application.
Transmission Loss of Membrane-Type Acoustic Metamaterial with Negative Effective Mass
Authors: Lin Guo Chang , Chen Song Qiao , Li Yu Liang , Tan Hui Feng
Published: June 2017

The transmission loss (TL) of membrane-type acoustic metamaterials consisting of small mass and rubber membrane was studied. By establishing a mass-spring equivalent model of metamaterial structural unit, which regards rubber membrane as having the dual role of damping force and spring force, we demonstrated that effective mass density of this membrane-type acoustic metamaterial was negative in the band gap range by theoretical analysis. Based on the theory of plane wave propagation, we studied the sound insulation of this membrane-type acoustic metamaterial. The result showed that membrane-type metamaterial was based on the principle of dipole resonance, which made the membrane-type acoustic metamaterial appear high reflection and low transmission phenomenon so as to achieve the aim of reducing noise. By optimal design, the sound attenuation frequency range of this membrane-type acoustic metamaterial was reduced to 20Hz-100Hz, greatly enhancing the ability of this metamaterial in terms of low-frequency sound insulation. We obtained the distribution of sound intensity at the optimum transmission frequency and the best reflection frequency by coupled acoustic-structural analysis. The best sound insulation frequency was matched with the second order and the third order eigenfrequency of this membrane-type acoustic metamaterial unit, and the strain energy was concentrated at the joint of small mass and the membrane. The total sound insulation of acoustic metamaterial plate was better than the single metamaterial unit.
Viscosity and Structure of KDP Aqueous Solution
Authors: Wu Yu Lin , Su Yi , Liu Yao , Wang Yong , Zhang Lei , Qu Yun Peng , He Yi , Han Xin Xin
Published: June 2017

The corresponding relationship among KDP solution viscosity, concentration and temperature was researched respectively, to explore the empirical formula of the viscosity of KDP solution. The experimental results showed that the viscosity increased with the increase of ionic strength and reciprocal of temperature. Viscosity had exponent relation to ionic strength and reciprocal of temperature, fitting in well with the empirical formula: See formula in paper. The X-ray diffraction analysis showed that with the increasing amount of KDP, a new peak emerging in the diffraction spectrum accorded with molecular structure of KDP crystals, and some peaks which accorded with the structural features of water molecules gradually disappeared. It showed that with the increase of the amount of KDP, the internal structure of KDP solution had changed.
Viscosity of Potassium Dihydrogen Phosphate Aqueous Solution within Magnetic Field
Authors: Zhang Lei , Su Yi , Wu Yu Lin , Liu Yao , Wang Yong , Qu Yun Peng
Published: June 2017

The viscosity of potassium dihydrogen phosphate, KH2PO4 (KDP), aqueous solution within magnetic field was studied. Experimental results showed that, the viscosity of saturated KDP solution exhibited multiple extreme values when the magnetic field intensity increased from 0 Gs to 2250 Gs. Influences of the magnetic field intensity on the viscosity of KDP solution were very complicated. It’s concerned with the temperature and the concentration of solution. As the KDP was produced from aqueous solution within magnetic field, the temperature and the concentration of solution also needed to be carefully controlled. Magnetic field with intensity values of 300 Gs, 600 Gs and 1800 Gs, all have the strong effects on the structures of KDP aqueous solution.
Improvement of Mechanical Properties and Corrosion Resistance by Deformation Induced Precipitation in Al-Zn-Mg-Cu Alloy
Authors: Zuo Jin Rong , Hou Long Gang , Shi Jin Tao , Cui Hua , Zhuang Lin Zhong , Zhang Ji Shan
Published: June 2017

A final thermomechanical treatment (FTMT) including peak aging and subsequent dynamic aging was proposed to prepare 7055 Al alloy sheets. The optimization was based on nine well-planned orthogonal experiments. Three main processing conditions in the thermomechanical treatment for obtaining the optimum synthetic properties of 7055 (i.e. preheating temperature, final rolling temperature and deformation degree) were investigated. It was shown that the final rolling temperature is the most important factor among the three parameters, and the optimum properties (yield strength: 651 MPa, ultimate tensile strength: 660 MPa) of 7055 Al alloy sheet can be gained with preheating at 140oC and 40% deformation at 170oC. With dynamic aging, grain boundary precipitates became discontinuous without much coarsening of matrix precipitates, while they were continuously distributed after T6 aging. The present optimal FTMT process can improve the intergranular / exfoliation corrosion resistance without sacrificing the strength compared to T6 tempering. The present FTMT process as a good alternative can produce high-strength Al alloy sheets with high strength and good corrosion resistance efficiently and economically.