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  • Fiscal expenditures on science and technology and environmental pollution: evidence from China

    Xiong, Wanfang; Han, Yan; Crabbe, M. James C.; Yue, Xiao-Guang; Huazhong University of Science and Technology; Beijing Institute of Technology; Oxford University; Shanxi University; University of Bedfordshire; European University Cyprus; et al. (MDPI, 2020-11-25)
    Studying the driving factors of environmental pollution is of great importance for China. Previous literature mainly focused on the cause of national aggregate emission changes. However, research about the effect of fiscal expenditures on science and technology (FESTs) on environmental pollution is rare. Considering the large gap among cities in China, it is necessary to investigate whether and how FESTs affect environmental pollution among cities. We adopted three kinds of typical environmental pollutants including sulfur dioxide (SO2) emissions, wastewater emission, and atmospheric particulate matter less than 2.5 micrometers in diameter (PM2.5). Using the data of 260 prefecture-level cities over ten years in China, we found that FESTs play a significantly positive role in reducing sulfur dioxide (SO2) emissions and PM2.5 concentrations, but fail to alleviate wastewater emissions. Specifically, for every 1% increase in FESTs, SO2 emissions were reduced by 5.317% and PM2.5 concentrations were reduced by 5.329%. Furthermore, we found that FESTs reduced environmental pollution by impeding fixed asset investments and by promoting research and development activities (R&D). Moreover, the impacts of FESTs on environmental pollution varied across regions and sub-periods. Our results are robust to a series of additional checks, including alternative econometric specifications, generalized method of moments (GMM) analysis and overcoming potential endogeneity with an instrumental variable. Our findings confirm that government efforts can be effective on pollution control in China. Hence, all governments should pay more attention to FESTs for sustainable development and environmental quality improvements.
  • An investigation into in-cylinder tumble flow characteristics with variable valve lift in a gasoline engine

    Wang, Tianyou; Liu, Daming; Tan, Bingqian; Wang, Gangde; Peng, Zhijun; Tianjin University; University of Hertfordshire (Kluwer Academic Publishers, 2014-10-31)
    In this paper, the investigation into in-cylinder tumble flow characteristics with reduced Maximum Valve Lifts (MVL) is presented. The experimental work was conducted in a modified four-valve Spark-Ignition (SI) test engine, with optical accesses for measuring in-cylinder air motion in the vertical direction. Three different MVL of 6.8 mm, 4.0 mm and 1.7 mm were tested and Particle Image Velocimetry (PIV) was employed for those measurements. Measurement results were analysed by examining the tumble flow field, the tumble ratio variation and the fluctuating kinetic energy distribution. Meanwhile, a numerical analysis method for detecting the vortex centre was developed. From results of the vortex centre distribution, the cyclic variation of the in-cylinder flow was explored. The phase-averaged flow fields show that higher MVLs could produce stronger vertical flows which turn more toward to the piston top and finally are possible to form big scale tumble flow structure. Although lower MVLs create a higher tumble ratio when the piston is close to the Bottom Dead Centre (BDC), higher MVLs substantially produce higher tumble ratios when the piston is moving close to the Top Dead Centre (TDC). In terms of kinetic energy, lower MVLs result in higher values including higher total kinetic energy and higher fluctuating energy. Finally, the vortex centres results demonstrate lower MVLs could enhance cycle-to-cycle variation due to the weakened tumble vortex.
  • The origins and adaptations of English as a school subject

    Goodwyn, Andrew (Cambridge University Press, 2019-12-31)
    This chapter will consider the particular manifestation of English as a ‘school subject’, principally in the country called England and using some small space for significant international comparisons, and it will mainly focus on the secondary school version. We will call this phenomenon School Subject English (SSE). The chapter will argue that historically SSE has gone through phases of development and adaptation, some aspects of these changes inspired by new theories and concepts and by societal change, some others, especially more recently, entirely reactive to external impositions (for an analysis of the current position of SSE, see Roberts, this volume). This chapter considers SSE to have been ontologically ‘expanded’ between 1870 and (about) 1990, increasing the ambition and scope of the ‘subject’ and the emancipatory ideology of its teachers. This ontological expansion was principally a result of adding ‘models’ of SSE, models that each emphasise different epistemologies of what counts as significant knowledge, and can only exist in a dynamic tension. In relation to this volume, SSE has always incorporated close attention to language but only very briefly (1988–1992) has something akin to Applied Linguistics had any real influence in the secondary classroom. However, with varying emphasis historically, there has been attention (the Adult Needs/Skills model, see later) to the conventions of language, especially ‘secretarial’ issues of spelling and punctuation, some understanding of grammar, and a focus on notions of Standard English, in writing and in speech; but these have never been the driving ideology of SSE. Of the two conceptual giants ‘Language’ and ‘Literature’, it is the latter that has mattered most over those 120 years.
  • On the simultaneous inversion of micro-perforated panels' parameters: application to single and double air-cavity backed systems

    Tayong-Boumda, Rostand; Manyo Manyo, Jacques A.; Siryabe, Emmanuel; Ntamack, Guy E.; University of Bristol; Université de Ngaoundéré; Université du Havre (Acoustical Society of America, 2018-04-20)
    This study deals with the deduction of parameters of Micro-Perforated Panel (MPP) systems from impedance tube data. It is shown that there is an ambiguity problem that exists between the MPP thickness and its open area ratio. This problem makes it difficult to invert the reflection coefficient data fitting and therefore to deduct the MPP parameters. A technique is proposed to reduce this ambiguity by using an equation that links the hole diameter to the open area ratio. Reflection coefficient data obtained for two specimens with different characteristics is employed for searching the MPP parameters using a simulated annealing algorithm. The results obtained demonstrate the effectiveness of this technique.
  • Wrinkle measurement in glass-carbon hybrid laminates comparing ultrasonic techniques: a case study

    Larrañaga-Valsero, Beatriz; Smith, Robert A.; Tayong-Boumda, Rostand; Fernández-López, Antonio; Güemes, Alfredo; Universidad Politécnica de Madrid; University of Bristol (Elsevier Ltd, 2018-08-15)
    Wrinkles, (also known as out-of-plane waviness) are, unfortunately, a common phenomenon that has caused some wind-turbine blades to unexpectedly fail in service. Being able to detect the wrinkles while in the factory will reduce the risk of catastrophic failure and characterising the wrinkles would minimise the repaired area, thus increasing the efficiency of the repair and the design. This work compares the effectiveness of three different ultrasound techniques for detecting and characterising out-of-plane wrinkles in the typical glass-carbon hybrid laminates that are used for wind-turbine blades. The tests samples were manufactured so that the laminates and the defects are representative of those used in the wind-turbine industry. Basic mechanical tests were performed to check the drop in mechanical properties due to wrinkling. The ideal probe frequency was determined as the resonance frequency of the plies using an analytical ultrasonic-propagation model. The three different ultrasound techniques used are: full-matrix capture (FMC) with the total focusing method (TFM), a commercial phased-array instrument and an immersion test with a raster-scanned single-element focused probe. When possible, severity parameters of the wrinkle were measured on the ultrasonic images and compared with the measurements of the actual sample in order to determine which method best characterises such wrinkles and which would be more appropriate to implement in an industrial environment. Not all of the techniques allowed full characterisation of out-of-plane waviness on the specimens. The FMC/TFM method gave better results whilst phased-array technology and single-element immersion testing presented more challenges. An additional enhancement to the TFM imaging was achieved using an Adapted-TFM method with an angle-dependent velocity correction.

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