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The vibration of the rails is a significant source of railway rolling noise, often forming the dominant component of noise in the important frequency region between 400 and 2000 Hz. The purpose of the paper is to investigate the influence of the ground profile and the presence of the train body on the sound radiation from the rail.

Two-dimensional boundary element calculations are used, in which the rail vibration is the source. The ground profile and various different shapes of train body are introduced in the model, and results are observed in terms of sound power and sound pressure. Comparisons are also made with vibro-acoustic measurements performed with and without a train present.

The sound radiated by the rail in the absence of the train body is strongly attenuated by shielding due to the ballast shoulder. When the train body is present, the sound from the vertical rail motion is reflected back down toward the track where it is partly absorbed by the ballast. Nevertheless, the sound pressure at the trackside is increased by typically 0–5 dB. For the lateral vibration of the rail, the effects are much smaller. Once the sound power is known, the sound pressure with the train present can be approximated reasonably well with simple line source directivities.

Numerical models used to predict the sound radiation from railway rails have generally neglected the influence of the ground profile and reflections from the underside of the train body on the sound power and directivity of the rail. These effects are studied in a systematic way including comparisons with measurements.

This article focuses on the leadership development of young adults. The topic is of significant importance as leadership identity tends to form early in life, and its long-term implications contribute to leadership formation. The objective of this study was to gain insights into how leadership is constructed in young adults and how it is manifested in their preferred leadership identity.

This research was approached from a constructivist perspective, utilizing discourse analysis. The authors conducted a study involving 24 written essays by young individuals with a business background, in which they shared their early leadership experiences. Drawing upon a modified life story interview structure, the authors meticulously analyzed the content.

The authors identified eight discourses clustered into two groups according to the types of leadership orientation: toward oneself and toward others. The discourses in the toward oneself group consist of leadership as taking responsibility, leadership as courage, manifesting personal strengths and as a role/status. The toward others group includes discourses approaching leadership as balancing directivity, coordinating and organizing work, personalized approach and as performance management.

The major methodological limitations stem from the qualitative design per se. The findings based on qualitative data have limits in generalizing.

The authors' findings have practical implications for educators. The authors propose the utilization of critical self-reflection on early leadership experiences and self-narration as effective tools in nurturing and developing young leaders.

This paper underscores the importance of educating young leaders, as they can create a positive impact on their subordinates and society as a whole. By providing them with leadership skills, the authors initiate a chain reaction of influence that extends through different levels of leadership, leading to significant social change.

The authors' originality and contribution to the literature on leadership development lies in showcasing the diversity of perspectives on leadership among participants sharing a similar background and developmental stage. This holds valuable implications for educators working with this cohort.

The aim of this paper is to understand if service innovation (Helkkula et al., 2018), based on artificial intelligence (AI) systems, may guarantee healthcare service ecosystem (H-SES) well-being (Frow et al., 2019; Beirão et al., 2017), taking into account that many doubts relieved in terms of transparency may compromise the patients' perceived quality of health services provided through AI systems.

A literature review on service innovation, detected in terms of value co-creation, and service ecosystem, investigated in terms of well-being, is drawn. To analyze the implications of service innovation on a H-SES well-being, through the technology acceptance degree and predisposition to use by actors, a case study based on TAM-model 3 determinants as categories is carried out.

AI-based service innovation archetypes in healthcare may be considered as antecedents of the service ecosystem well-being conditions as long as they enable actors to co-create value. To make it possible, a patient-driven service innovation is necessary in order to mitigate the risks of its inactivity due to fears in terms of transparency.

Service innovation and service ecosystem well-being may be studied in an integrated way, with a multidisciplinary approach, and are linked by value co-creation, because only thanks a patient-driven service innovation is possible to foster service ecosystem well-being in healthcare.

The purpose of this paper we present a case study where the Swedish planning support system Citylab is applied to a Chinese case in Changzhou's Tianning District.

China's planning system is a vertical system based on policy development on the national level, policies which are to be implemented on local level. There is a gap between the ambitious central policies and the implementations on local levels. China is now exporting its planning model to other developing countries which makes it urgent to show examples of other strategies including more horizontal planning involving the public. The planning system in Sweden is based on a much more horizontal process. Therefore, the authors try to learn from Sweden's vertical planning system in the urban development environment of China.

A key message for policy makers in China is that systems like Citylab can play an important role in developing practical and scalable examples of more sustainable city districts. The paper concludes that a barrier for local sustainability planning in China is still lack of effective communication between local actors including the public.

The authors exemplified Changzhou Tianning District's practical exploration, thus proving the adapted Citylab method's practical operability. Based on the common problems faced by eco-city development in developing countries, the method framework of Citylab is applicable to other developing countries, with strong room for deduction and development.

This study aims to solve the problem of weld quality inspection, for the aluminum alloy profile welding structure of high-speed train body has complex internal shape and thin plate thickness (2–4 mm), the conventional nondestructive testing method of weld quality is difficult to implement.

In order to solve this problem, the ultrasonic creeping wave detection technology was proposed. The impact of the profile structure on the creeping wave detection was studied by designing profile structural test blocks and artificial simulation defect test blocks. The detection technology was used to test the actual welded test blocks, and compared with the results of X-ray test and destructive test (tensile test) to verify the accuracy of the ultrasonic creeping wave test results.

It is indicated that that X-ray has better effect on the inspection of porosities and incomplete penetration defects. However, due to special detection method and protection, the detection speed is slow, which cannot meet the requirements of field inspection of the welding structure of aluminum alloy thin-walled profile for high-speed train body. It can be used as an auxiliary detection method for a small number of sampling inspection. The ultrasonic creeping wave can be used to detect the incomplete penetration welds with the equivalent of 0.25 mm or more, the results of creeping wave detection correspond well with the actual incomplete penetration defects.

The results show that creeping wave detection results correspond well with the actual non-penetration defects and can be used for welding quality inspection of aluminum alloy thin-wall profile composite welding joints. It is recommended to use the echo amplitude of the 10 mm × 0.2 mm × 0.5 mm notch as the criterion for weld qualification.

This paper is a response to the doctrine that capital is incompatible with public ownership. The fundamental characteristics of modern productivity determine the co-existence of the market economy and capital relations.

Socialism can neither bypass the market economy nor “go beyond capital”; capital appears in two historical forms, including the private capital and the public capital. Public capital is the inevitable outcome of the inherent contradictions of public ownership in a socialist market economy.

It represents an economic relationship that compels individual labourers to provide surplus labour for the society. The combination of the strong accumulation function of public capital and the improvement of people's welfare is the main cause of China's development miracle.

The innovation impetus of the public capital and its “immunity” to the capitalist crisis highlight the tremendous power of socialism with Chinese characteristics in breaking free of the shackles of capitalism and continuously developing productive forces. Public capital demonstrates and will continue to demonstrate the historical legitimacy of socialism.

In this work, a microstrip antenna array for wireless power transfer (WPT) application is reported. The proposed 4 × 4 antenna array operating at 16 GHz is designed using a flexible Kapton polyimide substrate for a far-field charging unit (FFCU).

The proposed antenna is designed using the transmission line model on a flexible Kapton polyimide substrate. The finite element method (FEM) is used to perform the full-wave electromagnetic analysis of the proposed design.

The antenna offers −10 dB bandwidth of 240 MHz with beam width and broadside gain found to be 29.4° and 16.38 dB, respectively. Also, a very low cross-polarization level of −34.23 dB is achieved with a radiation efficiency of 36.67%. The array is capable of scanning −15° to +15° in both the elevation and azimuth planes.

The radiation characteristics achieved suggest that the flexible substrate antenna is suitable for wireless charging purposes.

The purpose of this study is to contribute with knowledge about how valid research data in biodiversity citizen science are produced through information practices and how notions of credibility and authority emerge from these practices.

Data were collected through an empirical, interview-based study of the information practices of 15 participants active in the vicinity of the Swedish biodiversity citizen science information system Artportalen. Interview transcripts were analysed abductively and qualitatively through a coding scheme by working back and forth between theory and data. Values of credibility, authority and validity of research data were unfolded through a practice-oriented perspective to library and information studies by utilising the theoretical lens of boundary objects.

Notions of credibility, authority and validity emerge through participant activities of transforming species observations to data, supplementing reports with objects of trust, augmenting identification through authority outreach and assessing credibility via peer monitoring. Credibility, authority and validity of research data are shown to be co-constructed in a distributed fashion by the participants and the information system.

The article extends knowledge about information practices in emerging, heterogeneous scholarly settings by focussing on the complex co-construction of credibility, authority and validity in relation to data production.

Over the past 20 years, China's infrastructure has developed at an extraordinary speed. The current literature mainly focuses on the effects of political incentives on the infrastructure. However, this paper indicates that the structural change of China's land regime is an important clue and that the supernormal development of China's infrastructure is an explicable result for that.

This paper theoretically proves that in a politically centralized and economically decentralized economic entity with a public land-ownership regime, the self-financing mechanism formed by local officials through regulation of the land-grant price is the primary factor that influences the optimal supply volume of infrastructure in a region, in addition to political and economic incentives, and whether the self-financing mechanism can be formed or not depends on the structure of a country's land regime, which can help to explain the difference between the development of infrastructure in China and that in other developing countries from a theoretical angle.

The paper suggests that the mode is facing an important transformation toward land reform and new-type urbanization construction, and the replication and promotion of China's experience in infrastructure construction are of further significance under the Belt and Road Initiative as it provides a method for helping developing countries to eliminate infrastructure bottlenecks.

Through the test of multinational panel data, the paper indicates that the structural change of China's land regime around 1990 had an overall effect on the supernormal development of infrastructure in China. The paper indicates that the “land-based development mode” of China's infrastructure indeed contributed to the supernormal development of infrastructure in China, but there are still some shortcomings in this mode.

A novel framework for expedited antenna optimization with an iterative prediction-correction scheme is proposed. The methodology is comprehensively validated using three real-world antenna structures: narrow-band, dual-band and wideband, optimized under various design scenarios.

The keystone of the proposed approach is to reuse designs pre-optimized for various sets of performance specifications and to encode them into metamodels that render good initial designs, as well as an initial estimate of the antenna response sensitivities. Subsequent design refinement is realized using an iterative prediction-correction loop accommodating the discrepancies between the actual and target design specifications.

The presented framework is capable of yielding optimized antenna designs at the cost of just a few full-wave electromagnetic simulations. The practical importance of the iterative correction procedure has been corroborated by benchmarking against gradient-only refinement. It has been found that the incorporation of problem-specific knowledge into the optimization framework greatly facilitates parameter adjustment and improves its reliability.

The proposed approach can be a viable tool for antenna optimization whenever a certain number of previously obtained designs are available or the designer finds the initial effort of their gathering justifiable by intended re-use of the procedure. The future work will incorporate response features technology for improving the accuracy of the initial approximation of antenna response sensitivities.

The proposed optimization framework has been proved to be a viable tool for cost-efficient and reliable antenna optimization. To the knowledge, this approach to antenna optimization goes beyond the capabilities of available methods, especially in terms of efficient utilization of the existing knowledge, thus enabling reliable parameter tuning over broad ranges of both operating conditions and material parameters of the structure of interest.