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The passive source localization (PSL) problem using angles of arrival (AOA), time differences of arrival (TDOA) or gain ratios of arrival (GROA) is generally nonlinear and nontrival. In this research, the purpose of this paper is to design an accurate hybrid source localization approach to solve the PSL problem. The inspiration is drawn from the fact that the bearings, TDOAs and GROAs are complementary in terms of their geometry properties.

The maximum-likelihood (ML) method is reexamined by using hybrid measurements. Being assisted by the bearings, a new hybrid weighted least-squares (WLS) method is then proposed by jointly utilizing the bearing, TDOA and GROA measurements.

Theoretical performance analysis illustrates that the mean-square error of the ML or WLS method can attain the Cramér-Rao lower bound for Gaussian noise over small error region. However, the WLS method has much lower computational complexity than the ML algorithm. Compared with the AOA-only, TDOA-only, AOA-TDOA, TDOA-GROA methods, the localization accuracy can be greatly improved by combining the AOAs, TDOAs and GROAs, especially for some specific geometries.

A novel bearing-assisted TDOA-GROA method is proposed for source localization, and a new hybrid WLS estimator is presented inspired from the fact that the bearings, TDOAs and GROAs are complementary in terms of their geometry properties.

This study is designed to identify the policy shift on migrant children's11There are various definitions of migrant children in urban China. In this research, migrant children refer to the children from rural areas who have resided with their parents at the urban areas for at least six months without local household registration status. education at national level in urban China22With the rapid socioeconomic development and urbanization in China, the definition of urban China is changing. In this research, urban China refers to the major cities in China, such as Beijing, Shanghai, Guangzhou, Tianjin, Chongqing, and so forth. during the past decades. Meanwhile, it is expected to explore the policy limitations reflected by the practice at school level regarding accommodating migrant children's education.

This study is conducted through policy review regarding education for migrant children and analysis of data collected through questionnaires and interviews at one public junior high school in Beijing.

This study identifies a positive change of involving migrant children in urban public schools. However, there is a need for flexible mechanism that can fully accommodate various needs regarding migrant children's education in urban public schools.

The study argues the necessity of a multipartnership for establishing a sustainable public education system for accommodating migrant children education in urban public schools.

Being different from other research on the same issue in urban China, this study leads a new round of discussion on the quality education for migrant children.

This case is written for those people who are interested in entrepreneurship, and to generate discussions on the Lean Start-up methodology, as well as other topics related to entrepreneurship and innovation.

It can be used with senior undergraduates, MBAs, EMBAs and senior executives.

In August 2011, Mars Ren and Gene Deng created a technology-based venture, Shanghai Tianhailu Network Information Technology Ltd. Filled with passion, they aspired to be the first “factory outlet” in China' hotel booking industry. To achieve this goal, they developed the Hotelvp app for mobile users. After 6:00 p.m. every day, users could book accommodation online in hotels above three-star standard for that same night at significant discounts. Hotels also benefited because they could sell their unsold room nights at the last minute and improve their revenue management. Ren and Deng were convinced that this win-win idea would take off. Unfortunately, it failed to fully satisfy either the users or the hotels. In spite of the founders' passion and energy, it was still acquired by a much more powerful player in the online sector, JD.com, in early 2014. This case is designed to stimulate in-depth discussions based on the question: What are the key obstacles when launching a startup and how to overcome them?

Through class discussion, it aims at teaching the student how to define and practice a start-up idea successfully by following the “Lean Start-up” methodology and/or take advantage of a practical tool, discovery-driven planning. Specifically, this case intends to teach students how: To identify and define a good start-up idea; To take actions based on the idea/opportunity, iterate and modify it along the way to create new start-ups, and finally lead the new start-ups to grow and succeed; To understand the key concepts, frameworks and theoretical logics of Lean Start-up methodology, and apply it in practice.

Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H₂S under different temperatures, pH and salinities.

In this paper, weight loss measurements and electrochemical measurements are used to evaluate the corrosion degree of zinc and ABS A steel.

Under the conditions involved in this work, it is shown that zinc is a nice sacrificial anode with the reason of its stable potential and excellent anode current efficiency according to the relevant standard. And it is also found that the hydrogen evolution does not occur on ABS A steel specimens. The potential difference between cathode and anode is suitable; thus, it can be concluded that each steel is well protected.

To the best of the authors’ knowledge, no other study has analyzed the protection mechanism and effect of zinc as sacrificial anode in H₂S-containing environments under high temperature at present.

Online reviews have been indicated to play an important role in consumers’ decision-making process, as supported by numerous studies. However, none of them has considered the neighborhood effect of online reviews. The purpose of this paper is to analyze the impact of neighbor store’s reviews on central store’s, along with the moderating effects of store density and product similarity.

Using data from dianping.com, this study conducts economic analysis accounting for endogeneity.

The results show that the neighbor store’s reviews exert a negative impact on that of central stores. Nevertheless, the relationship is moderated by store density and product similarity, such that the negative effect is stronger if there are a lot of stores around the central store, or if the neighbor store and central store provide similar products.

This study is the first to investigate the neighborhood effect of online reviews.

Laser-based powder bed fusion (LPBF) is a new method for forming thin-walled parts, but large cooling rates and temperature gradients can lead to large residual stresses and deformations in the part. This study aims to reduce the residual stress and deformation of thin-walled parts by a specific laser rescanning strategy.

A three-dimensional transient finite element model is established to numerically simulate the LPBF forming process of multilayer and multitrack thin-walled parts. By changing the defocus amount, the laser in situ annealing process is designed, and the optimal rescanning parameters are obtained, which are verified by experiments.

The results show that the annealing effect is related to the average surface temperature and scan time. When the laser power is 30 W and the scanning speed is 20 mm/s, the overall residual stress and deformation of the thin-walled parts are the smallest, and the in situ annealing effect is the best. When the annealing frequency is reduced to once every three layers, the total annealing time can be reduced by more than 60%.

The research results can help better understand the influence mechanism of laser in situ annealing process on residual stress and deformation in LPBF and provide guidance for reducing residual stress and deformation of LPBF thin-walled parts.

This paper aims to find a way to improve the surface insulation, corrosion resistance and mechanical properties of Fe-Cr-Al electrothermal alloy, exploring the best oxidation condition and analyzing the oxidation mechanism.

Electrochemical workstation was used for anodic oxidation, and the effect of current density, ethylene glycol concentration and oxidation time on properties of the film were investigated by resistivity test, scanning electron microscope, electrochemical tests (potentiodynamic polarization and electrochemical impedance spectroscopy) and mechanical tests, and the oxidation process was analyzed by X-ray photoelectron spectroscopy (XPS).

According to the potential-time curves of anodic oxidation and the analysis of XPS, the whole oxidation process can be divided into four stages. When the current density is 0.8 A/dm², the ethylene glycol concentration is 10%, and the oxidation time is 60 min, the film has the best corrosion protection, mechanical properties and surface morphology. The resistivity of the samples is about 13 orders magnitude than that of the matrix.

In this paper, a protective electrically insulating film was prepared by anodic oxidation in an alkaline electrolyte solution. The oxidation conditions were optimized and the oxidation mechanism was analyzed.

The paper aims to develop a framework to facilitate the evaluation of the complexities of working in multi-level governance and partnership and to assess the extent to which collaboration adds value in terms of both process and outcomes.

The paper applies the fuzzy analysis hierarchy process (FAHP) to the design of an evaluation framework for partnerships and uses data from a questionnaire survey in Wuhan, China, to validate the framework.

The paper finds that the effectiveness of multi-level governance and partnerships is primarily determined by such factors as clarity of framework for partnership, consensus on mission statement of strategic partnership, mechanisms for joint initiation and implementation of projects and removal of barriers to flow of resources.

The paper shows that policymakers need to adopt an evaluation approach to improve the effectiveness of multi-level governance and partnerships.

The paper provides a framework for building multi-level governance and partnerships in the Chinese context.

Numerical and experimental results for different oncoming base-flow conditions indicate that nonuniform trailing edge blowing (NTEB) can expand the performance range of compressors and reduce the thrust on the rotor, while the efficiency of the compressor can be improved by more than 2 per cent.

Relevant aerodynamic parameters, such as total pressure, ratio of efficiency and axial thrust, are calculated and analyzed under conditions with and without NTEB. Measurements are performed downstream of two adjacent stator blades, at seven equidistantly spaced reference locations. The experimental measurement of the interstage flow field used a dynamic four-hole probe with phase lock technique.

An axial low-speed single-stage compressor was established with flow field measurement system and nonuniform blowing system. NTEB was studied by means of numerical simulations and experiments, and it is found that the efficiency of the tested compressor can be improved by more than 2 per cent.

Unlike most of the previous research studies which mainly focused on the rotor/stator interaction and trailing edge uniform blowing, the research results summarized in the current paper on the stator/rotor interaction used inlet guide vanes for steady and unsteady calculations. An active control of the interstage flow field in a low-speed compressor was used to widen the working range and improve the performance of the compressor.

Using the Environmental Kuznets Curve (EKC) hypothesis as a theoretical framework and applying Estimated Generalised Least Square (EGLS) approach, this chapter examines the impact of energy consumption, economic growth, industrialisation and corruption on carbon dioxide emissions as well as finds out the causal relationship among them using panel data of 10 Asian economies over the period 1980–2019. Our empirical findings from EGLS model suggest that there exists an ongoing rising relationship between CO₂ emissions and economic growth both in the short-run and long-run which is opposing to what is claimed by the EKC hypothesis. Moreover, per capita CO₂ emissions rise positively with respect to increase in energy consumption, urbanisation, gradual industrialisation and growth in urban population in the long-run. Moreover, countries with adoption of more corruptive practices are found to have causing more environmental degradation through excessive emission of carbon dioxide in the long-run. The study also indicates the existence of unidirectional causalities running from carbon dioxide emission to energy consumption, from industrialisation and urban population growth to per capita CO₂ emissions, from industrialisation to GDP growth per capita and bidirectional causality between financial development and economic growth via GDP growth per capita. Therefore, these unidirectional causalities entail that CO₂ emission reduction or abatement measures can be applied without having any unpleasant effect on the real industrialisation, energy consumption and urbanisation in selected Asian countries.