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This paper aims to investigate magnetic field anneal in micro-patterned Co-based amorphous ribbon on giant magneto-impedance (GMI) effect enhancement.

The amorphous ribbons were annealed in transverse and longitudinal magnetic field. The influence of different field annealing directions on GMI effect and impedance Z, resistance R and reactance X with a series of line width have been deeply analyzed.

In comparison with GMI sensors microfabricated by unannealed and transversal field annealed ribbons, GMI sensor which was designed and microfabricated by longitudinal field anneal ribbon performs better. The results can be explained by the domain wall motion and domain rotation during annealing process and the geometric structure of Co-based GMI sensor. In addition, shrinking the line width of GMI sensor can promote GMI effect significantly because of the effect of demagnetizing field, and the optimum GMI ratio is 209.7 per cent in longitudinal field annealed GMI sensor with 200 μm line width.

In conclusion, annealing in longitudinal magnetic field and decreasing line width can enhance GMI effect in micro-patterned Co-based amorphous ribbon.

In order to avoid the problem of volumetric locking often encountered when using constant strain tetrahedral finite elements, the purpose of this paper is to present a new composite tetrahedron element which is especially designed for the combined finite-discrete element method (FDEM).

A ten-noded composite tetrahedral (COMPTet) finite element, composed of eight four-noded low order tetrahedrons, has been implemented based on Munjiza’s multiplicative decomposition approach. This approach naturally decomposes deformation into translation, rotation, plastic stretches, elastic stretches, volumetric stretches, shear stretches, etc. The problem of volumetric locking is avoided via a selective integration approach that allows for different constitutive components to be evaluated at different integration points.

A number of validation cases considering different loading and boundary conditions and different materials for the proposed element are presented. A practical application of the use of the COMPTet finite element is presented by quantitative comparison of numerical model results against simple theoretical estimates and results from acrylic fracturing experiments. All of these examples clearly show the capability of the composite element in eliminating volumetric locking.

For this tetrahedral element, the combination of “composite” and “low order sub-element” properties are good choices for FDEM dynamic fracture propagation simulations: in order to eliminate the volumetric locking, only the information from the sub-elements of the composite element are needed which is especially convenient for cases where re-meshing is necessary, and the low order sub-elements will enable robust contact interaction algorithms, which maintains both relatively high computational efficiency and accuracy.

This paper aims to explore the influence of the reinforcement included either glass beads (GBs) or carbon fiber (CF) on the reinforced polyamide 12 (PA12) composite samples prepared by selective laser sintering (SLS).

In this paper, the microstructure and mechanical properties are investigated, and the results are compared with those obtained for non-reinforced pure PA12 samples prepared by SLS.

The tensile fracture surface of the non-reinforced pure PA12 sample presents strong micro-deformation within the crack origination zone between the melted PA12 matrix and the un-melted PA12 particle cores. As a result, the pure PA12 sample exhibits the greatest maximum elongation. The maximum tensile strength is obtained for the CF reinforced sample because of the strengthening effect of CF and the relatively good bonding between CFs and the PA12 matrix. The minimum tensile strength is obtained for the GB reinforced PA12 sample because of the relatively weak bonding between GBs and the PA12 matrix.

These results demonstrate that the characteristics of the interfaces between the reinforcement and the PA12 matrix have an important influence on the fracture mechanisms and mechanical properties of PA12 composites fabricated by SLS.

The US Department of Agriculture (USDA), Soil Conservation Services (SCS) rainfall-runoff model has been applied worldwide since 1954 and adopted by Malaysian government agencies. Malaysia does not have regional specific curve numbers (CN) available for the use in rainfall-runoff modelling, and therefore a SCS-CN practitioner has no option but to adopt its guideline and handbook values which are specific to the US region. The selection of CN to represent a watershed becomes subjective and even inconsistent to represent similar land cover area. In recent decades, hydrologists argue about the accuracy of the predicted runoff results from the model and challenge the validity of the key parameter, initial abstraction ratio coefficient (λ) and the use of CN. Unlike the conventional SCS-CN technique, the proposed calibration methodology in this chapter discarded the use of CN as input to the SCS model and derived statistically significant CN value of a specific region through rainfall-runoff events directly under the guide of inferential statistics. Between July and October of 2004, the derived λ was 0.015, while λ = 0.20 was rejected at alpha = 0.01 level at Melana watershed in Johor, Malaysia. Optimum CN of 88.9 was derived from the 99% confidence interval range from 87.4 to 96.6 at Melana watershed. Residual sum of square (RSS) was reduced by 79% while the runoff model of Nash–Sutcliffe was improved by 233%. The SCS rainfall-runoff model can be calibrated quickly to address urban runoff prediction challenge under rapid land use and land cover changes.

This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

The GMI sensor contains a Co-based internal magnetic core fabricated by laser cutting and an external solenoid. The influences of magnetic permeability of magnetic core and structure parameters on GMI effect were calculated in theoretical model. The output impedance, resistance, reactance and GMI ratio were measured by non-contact method using impedance analyzer.

Enhancing external magnetic field intensity can decrease the magnetic permeability of core, which has vital influences on the magnetic property and the output response of GMI sensor. In addition, increasing the width of magnetic core and the number of solenoid turns can increase the maximum GMI ratio. The maximum GMI ratio is 3,230% with core width of 6 mm and solenoid turns of 200.

Comparing with traditional contact-measured GMI sensor, the maximum GMI ratio and the magnetic field sensitivity are improved and the power consumption is decreased in non-contact measured GMI sensor. GMI sensor measured by non-contact method has a wide range of potential applications in ultra-sensitive magnetic field detection.

In the long-term network operation, the power distribution network will be subjected to the effects of ultra-high voltage, strong electromagnetic interference and harsh natural environment on the power system, which will lead to the occurrence of different faults in the distribution network and directly affect the normal operation of the power grid.

The purpose of this study is to solve the problems of labor intensity, high risk and low efficiency of distribution network manual maintenance operation, this paper proposed a new configuration of the live working robot for distribution network maintenance, the robot is equipped with dual working arms through the mobile platform, which can realize the coordination movement, the autonomous reorganization and replacement of the end tools, respectively, so as the robot power distribution maintenance function such as stripping, trimming, wiring and the operation control problem of the distribution network-robot with small arms and in small operation space can be realized.

To effective elimination or reduce the adverse effects of the internal forces in the closed chain between the working object and manipulator under the typical task of the 10 kV distribution network, this paper has established the robot coordinated control dynamics model in the closed-chain between the dual-working object and proposed the dynamic distribution method of closed-chain internal force and the effectiveness has been proved by simulation experiments and 10 kV field operation.

The force-position hybrid control can realize the mutual compensation of force and position so as to effectively reduce the internal force in the closed chain. Finally, the engineering practicality of the method is verified by field operation experiment, the effective implementation of this control method greatly improves the robot working efficiency and the operation reliability, the promotion and application of the control method have great theoretical and practical value and maintenance management system, so as to achieve automation of electric.

The relationship between sustainable development and private finance initiative (PFI) procurement systems is clarified, and the current debate on the effectiveness of PFI in the UK and the benefits of PFI to deliver sustainable construction is reviewed. The study develops a sustainability assessment framework encompassing environmental, economic, social and technical aspects through the life cycle of the procurement process. The paper aims to discuss these issues.

A comprehensive literature review develops a conceptual sustainability performance indicators framework. A national questionnaire survey measures existing PFI projects' sustainability performance level.

The study provides empirical insights about key performance indicators of sustainable PFI project development and a benchmarking for existing PFI project performance measurement. It suggests that successful sustainable PFI projects should integrate technical aspects into the traditional three dimensions sustainability model and achieve a balance between social and economic performance.

Because of the chosen research approach, the research results may lack in-depth analysis of individual projects. Therefore, researchers are encouraged to test the framework further.

The sustainability indicator framework proposed in this paper is readily applicable in PFI projects, as well as other types of PPP projects.

This paper fulfils an identified need to study how the sustainability performance levels achieved could be effectively measured within PFI/PPP projects; while contributing to the debate on benchmarking and measuring sustainability performance in construction.

The purpose of this paper is to identify and assess the perceptions of stakeholders on critical success factors (CSFs) for Public Private Partnership (PPP) projects in Nigeria.

A comprehensive literature review was conducted to identify the CSFs for PPP projects, which were employed to design a questionnaire survey. In order to capture a broad perception of stakeholders, the questionnaires were administered to five different stakeholder organisations involved in different PPP projects implementation in Nigeria. Data collected were analysed using descriptive statistics, mean score, Kruskal-Wallis test, analysis of variance (ANOVA), and factor analysis.

The study revealed the result of mean score ranking, which indicated that all the stakeholders considered the identified 26 CSFs important and crucial for the successful implementation of PPP projects in Nigeria. Thus, the results of Kruskal-Wallis test and ANOVA indicated that except for six (out of 26) identified CSFs, there is no statistically significant difference in the perceptions of the stakeholders on CSFs for PPP projects in Nigeria. The study, through factor analysis, grouped the 26 identified CSFs into six principal factors.

This research would be of benefit to stakeholders in PPPs to be aware of CSFs that demand utmost consideration. Also the identified CSFs are expected to enhance the success rate of PPP projects.

The findings would be useful for PPP stakeholders in making decisions and in implementing PPP projects towards achieving value for money. This research will also be of interest to other academic researchers intending to investigate CSFs for PPP projects in other locations.

With the development of tourism industry, online travel agencies (OTA) have gradually become an important channel for tourism product supplies and sales. Some OTAs provide consumers with a platform for tourism guidance and online travel sharing. They not only satisfy some tourists’ desire to share their experiences but also provide reference for more consumers to choose travel products. This process is the process of value co-creation by customers and online travel companies. This study is conducted under DART theory, a theoretical framework of value co-creation composed of four dimensions, namely dialog, access, risk-assessment, and transparency. Brand equity is divided into four aspects: brand loyalty, brand awareness, customer perceived value, and brand image. This study uses the structural equation model to investigate the impact of customer value co-creation behavior on brand equity of online travel enterprises and interprets the process and mechanism of customer value co-creation behaviors for online travel business brand equity, which provides more efficient strategies and methods for platform interaction and value co-creation.

The purpose of this study is to use critical success factors (CSFs) to develop a process maturity and determine the current maturity levels of stakeholder organisations in public–private partnership (PPP) project implementation in Nigeria. The success of any PPP project is largely dependent on the country’s maturity on CSFs that made PPP projects successful. Thus, the identification of metrics and standards for measuring the maturity of stakeholder organisations on CSFs for PPP project implementation remains a challenge.

The study adopted literature review and six PPP project case studies including interviews in each case study and expert forum. The outcome of a comprehensive literature review provides a total list of 14 CSFs that made PPP projects successful in Nigeria. These CSFs were used for capability maturity levels ' definition ranging from level 1 (Ad hoc) to level 5 (Optimising) in line with capability maturity model concept. Quantitative assessment was considered as a support tool for making an overall assessment of both the public and private organisations ' current capability maturity levels and for comparison approach.

A capability enhancement framework for stakeholder organisations in PPP project was developed. This framework was used in assessing the current capability maturity levels of stakeholder organisations involved in PPP projects in Nigeria. Using this framework, it was found that public sector organisations were positioned between maturity level 1 and maturity level 2 (out of five maturity levels) on CSFs applicable to them. While, most private sector organisations were placed in maturity level 2 on CSFs associated with them.

The results emanated from this study provided both the theoretical and practical implications. The theoretical implication provides new insights into the usefulness of CSFs in PPP projects and indicates that merely identifying possible CSFs for PPP projects is not sufficient. The practical implication shows that the framework developed in this study had provided the benchmark for the identification of methodical approach, and standard to process improvement in PPP infrastructure projects, which can be replicated in both the developed and developing countries. Thus, the framework could be used to benchmark future studies.

The framework would provide a useful guide and roadmaps for improvement by indicating “what” needs to be done by stakeholder organisations involved in PPP projects in achieving higher capability maturity levels on identified CSFs for PPP projects in Nigeria and developing countries at large.