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Among the proposed radio access strategies for improving system execution in 5G networks, the non-orthogonal multiple access (NOMA) scheme is the prominent one.

Among the most fundamental NOMA methods, power-domain NOMA is the one where at the transmitter, superposition coding is used, and at the receiver, successive interference cancellation (SIC) is used. The importance of power allocation (PA) in achieving appreciable SIC and high system throughput cannot be overstated.

This research focuses on an outage probability analysis of NOMA downlink system under various channel conditions like Rayleigh, Rician and Nakagami-m fading channel. The system design's objectives, techniques and constraints for NOMA-based 5G networks' PA strategies are comprehensively studied.

From the results of this study, it is found that the outage probability performance of downlink ordered NOMA under Rayleigh, Rician and Nakagami-m fading channel was good.

Outage probability analysis of downlink ordered NOMA under various channel conditions like Rayleigh, Rician and Nakagami-m fading channels were employed. Though the performance of Nakagami-m fading channel is lesser compared to Rayleigh channel, the performance for user 1 and user 2 are good.

This paper aims to elucidate the relationship between entrepreneurial orientation, reverse innovation and international performance of emerging economy multinational enterprises (EMNEs).

The authors analyze archival data of Chinese limited companies between 2010 and 2016, including 11,230 firm-year observations about 1708 firms. In order to test the study’s mediation hypotheses, the authors apply an ordinary least square (OLS) regression.

The authors find evidence that the entrepreneurial orientation of EMNEs has a positive effect on reverse innovations. Furthermore, the authors find positive effects of reverse innovation on the international performance of EMNEs. This pattern of results suggests that the relationship between entrepreneurial orientation and international performance is partially mediated by reverse innovation.

The study’s findings help managers in EMNEs to promote reverse innovation by building and using their entrepreneurial orientation. It also helps them to set out and gauge the chances of success of their internationalization strategies. The findings also hold relevance for firms in developed economies as well, as they may understand which emerging economy competitors stand to threaten their positions.

The strategic role of reverse innovations – i.e. clean slate, super value and technologically advanced products originating from emerging markets – has generated considerable research attention. It is clear that reverse innovations impact the international performance of EMNEs. Yet how entrepreneurial orientation influences international performance is still underexplored. Thus, the current study clarifies the mechanism by examining and testing the mediating role of reverse innovation among the entrepreneurial orientation–international performance link.

With the growing climate problem, it has become a consensus to develop low-carbon technologies to reduce emissions. Electric industry is a major carbon-emitting industry, accounting for 35% of global carbon emissions. Universities, as an important patent application sector in China, promote their patent application and transformation to enhance Chinese technological innovation capability. This study aims to analyze low-carbon electricity technology transformation in Chinese universities.

This paper uses IncoPat to collect patent data. The trend of low-carbon electricity technology patent applications in Chinese universities, the status, patent technology distribution, patent transformation status and patent transformation path of valid patent is analyzed.

Low-carbon electricity technology in Chinese universities has been promoted, and the number of patents has shown rapid growth. Invention patents proportion is increasing, and the transformation has become increasingly active. Low-carbon electricity technology in Chinese universities is mainly concentrated in individual cooperative patent classification (CPC) classification numbers, and innovative technologies will be an important development for electric reduction.

This paper innovatively uses valid patents to study the development of low-carbon electricity technology in Chinese universities, and defines low-carbon technology patents by CPC patent classification system. A new attempt focuses on the development status and direction in low-carbon electricity technology in Chinese universities, and highlights the contribution of valid patents to patent value.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

The purpose of this paper is to establish a chair-side design and production method for a tooth-supported fixed implant guide and to evaluate its accuracy.

Three-dimensional (3D) data of the alveolar ridge, adjacent teeth and antagonistic teeth were acquired from models of the edentulous area of 30 patients. The implant guides were then constructed using self-developed computer-aided design software and chair-side fused deposition modelling 3D-printing and positioned on a dental model. A model scanner was used to acquire 3D data of the positioned implant guides, and the overall error was then evaluated.

The overall error was 0.599 ± 0.146 mm (n = 30). One-way ANOVA revealed no statistical differences among the 30 implant guides. The gap between the occlusal surface of the teeth covering and the tissue surface of the implant guide was measured. The maximum gap after positioning of the implant guide was 0.341 mm (mean, 0.179 ± 0.019 mm). The implanted axes of the printed implant guide and designed guide were compared in terms of overall, lateral and angular error, which were 0.104 ± 0.004 mm, 0.097 ± 0.003 mm, and 2.053° ± 0.017°, respectively.

The results of this study demonstrated that the accuracy of a new chair-side tooth-supported fixed implant guide can satisfy clinical requirements.

To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately, so as to better serve the comprehensive revision of the Regulations, this paper carries out the research on the traceability and evolution of the provisions of the Regulations.

This paper studies and analyzes the evolution of the 11th edition of the Regulations by analyzing the relevance of clauses and summarizes the historical background of the development of calendar editions of the Regulations. The basic research on the traceability and evolution of the Regulations is carried out from four aspects: the continuity of the development of the Regulations, the authority of contents, the relevance of clauses and the richness of historical materials.

From the first edition of the Regulations issued by the former Ministry of Railways in 1950 to the 11th edition, there have been ten comprehensive revisions. There is a strong correlation and continuity between the calendar editions of the Regulations in terms of chapter structure and clauses. Studying the context of the terms of the Regulations is an important way to understand and master the current clauses of the Regulations.

Through the research on the traceability and evolution of the clauses of the Regulations, one is to explore the context of the development of railway technical equipment in China, the other is to clarify the historical background when the provisions were formulated and the third is to trace the development and evolution of the provisions. The revision of the Regulations is based on an accurate grasp of the context of the provisions, which can effectively judge the possible security risks caused by the revision of the provisions and avoid the possible risks in field implementation from the source.

China's economic transition is essentially the process of China's institutional changes. During the changes, the appearance of institutional innovation is not regular; instead, it is intermittent and random. The purpose of this paper is to show that the fitful appearance of institutional innovation is the root of China's economic growth and fluctuations.

This paper constructs a real business cycle (RBC) model introducing the institutional factor expressed in the quantitative form under the dynamic stochastic general equilibrium (DSGE) framework by measuring China's institutional changes quantitatively.

By comparing the characteristics of the actual economic data with those of the simulated economic data, we find that this RBC model can explain 94.44%, 66.07%, 23.46%, 21.03% and 15.45% of the cyclical fluctuations in output, investment, labor, consumption and capital, respectively.

The impulse response analysis finds that the institutional shocks have a relatively long duration, lasting about 30 years, and decline slowly over time, while technological shocks decline relatively fast, lasting approximately ten years.

The paper aims to clarify the operation rationality of high speed trains (HSTs) under tunnel condition with the speed of 400 km/h through representative aerodynamic factors including running drag, eardrum comfort, carriages noise, aerodynamic loads on tunnel ancillary facilities and HST, micro-pressure waves, and then put forward engineering suggestions for higher speed tunnel operation based on the analysis.

Based on the field measurement data of CR400AF-C and CR400BF-J tunnel operation, correlations between each aerodynamic indicators with HST speed were established. By analyzing the safety reserve of aerodynamic indicators at 350 km/h and the sensitivity of each indicator to HST speed increasing and the indicators’ formation mechanism, the coupling relationship between various indicators was obtained.

The sensitivity of different aerodynamic indicators to speed variation differed. The aerodynamic indicators representing flow field around HST showed a linear relationship with HST speed including noise, eardrum comfort, aerodynamic load on HST body. The positive aerodynamic load on tunnel auxiliary facilities and the micro-pressure wave at the entrance of the tunnel have the same sensitivity to the 3th-power relation of HST speed. The over-limit proportion of micro-pressure wave was the highest among the indicators, and aerodynamic buffering measures were recommended for optimization. The open tunnel pressure relief structure is recommended, while allowing trains to pass through the tunnel at an unconditional speed of 380 km/h.

Comprehensive evaluation of multiple aerodynamic indicators for HST tunnel operation with higher speeds was realized. The main engineering requirements to release aerodynamic effect were identified and the optimization scheme is proposed.

Lebanon has been subject to important reforestation activities which resulted in the establishment of several cedars, pine and other mixed forest stands on communal lands. These stands are not designated for timber production but rather for nonwood forest products (NWFPs), landscape restoration and for environmental services. The study aims at valuating old reforested sites from the perspective of rural communities neighboring those reforested stands.

To assess the non-timber goods and services provided by these forest ecosystems, 13 reforested sites located in different regions in Lebanon were selected. The socioeconomic assessment was done using questionnaires distributed to locals that have close interactions with the neighboring forests; it included, among others, a double-bonded dichotomous contingent valuation (CV) related to their willingness to pay (WTP) for reforestation and forest management activities.

Results of the goods and services assessment revealed that the forests have multifunctional uses with ecotourism as a major activity in all forest types. The CV showed that 75% of respondents did express a WTP. Most of the respondents did so, thus giving a great importance to intrinsic values of the forests. Lower income did not negatively affect the WTP of respondents but rather age and the educational level did. Other factors such as forest type, forest surface and the biodiversity status of the sites did not have an impact on WTP.

These results are very informative for governmental policies seeking funds to perform reforestation programs for environmental objectives, involving local communities in co-funding these programs would help insure the sustainable conservation of reforestation sites.

Despite their relative low income, poor communities are willing to pay to sustain forests and their ecosystem services.

It is the first time that a CV is used for ecosystem services regenerated from 50–60 years old reforested sites in a semiarid region, where trees are not planted for timber production. It is one of the few examples were lower income did not affect the WTP for forests providing environmental services on communal lands.

Vertical line extension is an attractive growth strategy that allows brands to address heterogeneous consumer needs and react to competitive pressure. The purpose of this paper is to systematically review and summarize vertical line extension research to derive general insights into vertical upward and downward line extension.

Drawing on a systematic review of 536 academic articles and predefined inclusion criteria, this research identifies and evaluates all articles that add knowledge to the topic of vertical line extension (n = 64).

This research derives general insights in several vertical line extension-specific issues. Different forms of vertical line extension, conceptual differences between upward and downward extensions, as well as the role of perceived fit, extension degree and the parent brand are crucial for the study and evaluation of extension and parent brand feedback effects. Those effects are complex and often work in opposing directions not only for the parent brand but also for the extension. Future research needs to face that complexity as well as methodological issues and different research contexts to further advance the literature stream.

This paper provides a comprehensive, state-of-the-art review of vertical line extension research characteristics and results. It provides new insights on the characteristics and effects of vertical line extensions and guides future research on the topic.