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  • Integrated Detection of a Complex Underground Water Supply Pipeline System in an Old Urban Community in China

    Shifan Deng; Siyu Ma; Xiaowen Zhang; Shiqiang Zhang (MDPI AG, 2020-02-01)
    An underground water supply pipeline system is an integral part of urban infrastructure. The safety, stability, reliability, and efficiency of this water system are critical for the daily work and livelihood of the people dependent on it. However, with the development of cities in China, the water supply systems in urban communities require constant re-building and improvement, which complicates the system. Considering the defects of obsolete design, lack of information, and irregularity of the constructions over the years, the maintenance of underground pipelines in older communities is onerous and arduous. In this work, the older pipeline system at the Taibai campus of Northwest University, Shaanxi Province, was taken as one typical old urban community and investigated by different measures. Detection was performed from the available concentrated water supply wells to surrounding areas combining electromagnetic induction, geophysical method by ground-penetrating radar (GPR), and acoustic detection methods. Applying the integrated detection method and considering known pipeline network designs, the properties and complex relationships of different pipeline materials (cast iron, polyethylene (PE), and polyvinyl chloride (PVC)) were determined. In addition, a spatial distribution map of the pipes from wells and the main input water supply pipelines was achieved. The results suggest that the integrated detection scheme combining these three methods provides an effective approach to analyze complex water supply pipelines in older communities, in which each single detection method has more uncertainties. The study provides valuable references for similar communities in many developing countries.
  • Modeling Green Energy Development Based on Sustainable Economic Growth in China

    Zhijuan Zhang; Marcin Lis (MDPI AG, 2020-02-01)
    Industrial development of the economic system of any state is directly related to the use of energy potential. China’s industrial breakthrough is no exception. Today, China is one of the largest importers−consumers of oil, whose economy is extremely dependent on the energy market. The growing production and population, as well as climatic changes that directly determine the well-being of society, have become the causal basis for the development of alternative ways of generating energy. The aim of the study is to model the implementation of the sustainable development strategy in China through the production and use of biofuels. The simulation is made taking into account the following. The production capacities of Chinese licensed producers of fuel ethanol are calculated. The efficiency of bioethanol production from various types of biological raw materials is evaluated. An economic and mathematical model of bioethanol production is built. The article forecasts the profitability of bioethanol sales from various types of biological raw materials (sugar sorghum, corn) in Chinese and European markets. The study comprehensively reveals the features of the use of biofuels in an industrial country, taking into account geopolitical factors, social and market contexts, as well as technical analysis of the raw materials and production potential of Chinese companies. The article also interprets the economic processes associated with the introduction of biofuels in the ecological and economic systems of China. The article demonstrates other concepts regarding the consequences of the energy sector’s transition to the principles of energy production from biomass. The article shows the contradictory nature of the impact of biofuel production on the food market and the agricultural sector. The article analyzes possible social, resource and macroeconomic risks, and also indicates possible vectors for further research that might be aimed at diversifying the associated negative processes.
  • Technological Ecosystems in Citizen Science: A Framework to Involve Children and Young People

    Alicia García-Holgado; Francisco José García-Peñalvo; Paul Butler (MDPI AG, 2020-03-01)
    Young people are distinguished as a social group with the capacity to drive new behaviours and understandings in today’s society. However, most young people consider that people in charge of decision-making processes are not addressing their concerns. The WYRED project proposes a framework for citizen science based on a technological ecosystem to promote the transfer of perspectives, ideas, and knowledge among young people and decision-makers on issues related to the digital society. The work goal is to analyse the model proposed through a citizen science case study centred in identifying the ideas and opinions of children and young people between 7 and 30 years old, concerning gender stereotypes on the Internet. A total of 69 children and young people from Belgium, Italy, Spain, Turkey, Ukraine, and the United Kingdom have interacted for two weeks in a private space guaranteed by the defined ecosystem. The results of the analysis of the interaction between young people and facilitators (with different profiles: educators, researchers and decision-makers) demonstrate that the use of technological ecosystems to sustain the development of citizen science projects allows for the improvement of knowledge transfer processes between children and young people with stakeholders, as well as the analysis of these processes.
  • Adaptive Sustainable Reuse for Cultural Heritage: A Multiple Criteria Decision Aiding Approach Supporting Urban Development Processes

    Lucia Della Spina (MDPI AG, 2020-02-01)
    The European Union identifies the cultural heritage of cities as the main driver of development strategies. From this perspective, adaptive reuse can play a decisive role not only in terms of increasing the life cycle of the heritage but also as an urban strategy capable of generating new economic, cultural, and social values, thus supporting innovative dynamics of local development. The aim is to propose an integrated evaluation model based on the combined use of multi-criteria techniques, which helps to classify adaptive reuse strategies of unused cultural heritage assets and supports decision-makers in the implementation of development strategies in vulnerable contexts. The case study focuses on the potential reuse of some historical fortifications located along the coasts of the Strait of Messina in Southern Italy. The results obtained show that the proposed model can be a useful decision support tool, in contexts characterized by high complexity, able to guarantee the transparency of the decision-making process, and in which it is necessary to highlight the elements that influence the dynamics of the choice for the construction of shared development strategies.
  • Economic Valuation of Earth’s Critical Zone: A Pilot Study of the Zhangxi Catchment, China

    Wan Nie; Hongyan Guo; Lei Yang; Yaoyang Xu; Gang Li; Xiaohong Ruan; Yongguan Zhu; Liding Chen; Steven A. Banwart (MDPI AG, 2020-02-01)
    Earth’s critical zone is the physical layer contained between the top of the vegetation canopy and the depth of the circulating groundwater below the land surface. The critical zone is defined within the study of Earth natural sciences as the unique terrestrial biophysical system that supplies most life-sustaining resources for humans. A feature of this specific physical system that is defined by geographical locale is the interactions of people with the vertically-connected biophysical flows and transformations (energy, material, biodiversity) that contribute to human welfare by delivering, both directly and indirectly, critical zone services to humankind. We have characterized these interactions by considering the full extent of the critical zone through the application of economic valuation methods. We estimated the current economic value of 14 critical zone services for 5 biophysical components of Earth’s critical zone, based on data collected from the Zhangxi catchment of Ningbo city located in the Yangtze River Delta region of China and from several additional published studies. For the full vertical extent of Earth’s critical zone bounded by the Zhangxi catchment, the value, most of which is outside the market, was estimated to be USD 116 million in 2018. Valuation of goods and services was delineated for benefits arising from key components of the critical zone physical system. The estimated value of the atmospheric component of Earth’s critical zone was USD 5 million; the vegetation component value was USD 96 million; the soil component value was USD 8 million; the surface water component value was USD 5 million; and the groundwater component value was USD 2 million. Because of the nature of the uncertainties and lack of data for the full range of identified services, these values are considered a minimum estimate. Gross domestic product in the Zhangxi catchment was around USD 431 million in 2018. These results illustrate, for one location, the range of services that arise when considering the full depth of Earth’s critical zone, the data needs for valuing this range of services, and the conceptual and potential methodological advances, and the challenges, that exist at the disciplinary interface between Earth natural sciences and applied economics.
  • The Trivariate Causality among Education, Health, and Economic Growth in Zimbabwe

    Michael Takudzwa Pasara; Tapiwa Kelvin Mutambirwa; Nolutho Diko (MDPI AG, 2020-02-01)
    This study investigated the causality among education, health, and economic growth in Zimbabwe. Causality effects are a thinly explored area in literature, with most studies focusing on bidirectional relationships. Granger causality tests were employed in a Vector autoregressive (VAR) model. Results showed that education Granger causes health improvements, with health improvements in turn fairly associating to Granger cause economic growth in Zimbabwe. Thus, the effect of education on economic growth is not direct, but works through improved health, pointing to the conclusion that health is a transmission mechanism through which education drives economic growth. No feedback effect was established from health to education and from economic growth to education and health. Thus, results suggest the need for a holistic policy approach which integrates education and health policies in a bid to drive economic growth, since education has no effect on economic growth in its own domain, but through health.
  • A Framework to Evaluate Community Resilience to Urban Floods: A Case Study in Three Communities

    Ming Zhong; Kairong Lin; Guoping Tang; Qian Zhang; Yang Hong; Xiaohong Chen (MDPI AG, 2020-02-01)
    Community resilience is a key index for describing the response of human habitat systems to hazards. Evaluating and enhancing the community resilience requires indicators, identification, and quantitative measurements, especially for urban flooding management. In this study, an advanced index framework for measuring community resilience to urban flooding is proposed, integrating the fuzzy Delphi method (FDM) and the analytic network process (ANP). Seven indicators (public facilities, spatial structure of land use, flood management organizations, rescue capability, accuracy of weather forecasts, vulnerable population, and individual capability) of community resilience are identified using the fuzzy Delphi method. The indicators are classified into four dimensions, and the weights are determined by the analytic network process. This approach is applied to three different types of communities, namely, a newly built neighborhood, an ancient college, and a flood-prone village in the city of Nanning, China, using data collected from questionnaires, interviews, and field investigations. The neighborhood (with a total averaged score of 2.13) has the largest community resilience to urban flooding, followed by the college (1.8), and finally the village (0.91). Flooding management organizations play a leading role in the urban flooding resilience of the neighborhood and college, while the vulnerable population has a great impact on the community resilience of the village. Results of the strategy analysis suggest that science and technology improvement (0.543) is more important than social−economic status improvement (0.325) and built-environment improvement (0.132) for mitigating urban hazards in Nanning. The proposed framework in this study contributes to the interdisciplinary understanding of community resilience for urban flooding and is expected to be applied to sustain urban planning and flood evacuations.
  • Threat and Anxiety in the Climate Debate—An Agent-Based Model to Investigate Climate Scepticism and Pro-Environmental Behaviour

    Marie Lisa Kapeller; Georg Jäger (MDPI AG, 2020-02-01)
    In order to meet the challenges of sustainable development, it is of utmost importance to involve all relevant decision makers in this process. These decision makers are diverse, including governments, corporations and private citizens. Since the latter group is the largest and the majority of decisions relevant to the future of the environment is made by that group, great effort has been put into communicating relevant research results to them. The hope is that well-informed citizens make well-informed choices and thus act in a sustainable way. However, this common but drastic simplification that more information about climate change automatically leads to pro-environmental behaviour is fundamentally flawed. It completely neglects the complex social-psychological processes that occur if people are confronted with threatening information. In reality, the defence mechanisms that are activated in such situations can also work against the goal of sustainable development, as experimental studies showed. Based on these findings, we propose an agent-based model to understand the relation between threatening climate change information, anxiety, climate change scepticism, environmental self-identity and pro-environmental behaviour. We find that the exposure to information about climate change, in general, does not increase the pro-environmental intent unless several conditions regarding the individual’s values and information density are met.
  • Address Authentication Method for Sustainable Social Qualification

    Hosung Park; Seungsoo Nam; Daeseon Choi (MDPI AG, 2020-02-01)
    This paper proposes an address authentication method based on a user’s location history. Address authentication refers to actual residence verification, which can be used in various fields such as personnel qualification, online identification, and public inquiry. In other words, accurate address authentication methods can reduce social cost for actual residence verification. For address authentication, existing studies discover the user’s regular locations, called location of interest (LOI), from the location history by using clustering algorithms. They authenticate an address if the address is contained in one of the LOIs. However, unnecessary LOIs, which are unrelated to the address may lead to false authentications of illegitimate addresses, that is, other users’ addresses or feigned addresses. The proposed method tries to reduce the authentication error rate by eliminating unnecessary LOIs with the distinguishing properties of the addresses. In other words, only few LOIs that satisfy the properties (long duration, high density, and consistency) are kept and utilized for address authentication. Experimental results show that the proposed method decreases the authentication error rate compared with previous approaches using time-based clustering and density-based clustering.
  • Sustainable Animal Feed Protein through the Cultivation of <i>YARROWIA Lipolytica</i> on Agro-Industrial Wastes and by-Products

    Sotiris I. Patsios; Anna Dedousi; Evangelia Ν. Sossidou; Antonios Zdragas (MDPI AG, 2020-02-01)
    Proteins are essential constituents of animal feeds, which comprise mainly vegetable protein (e.g., soybean meal), which is produced and transported globally. The decoupling of protein-production and livestock-growth areas results in protein deficiencies in certain parts of the world, and in significant environmental stress. Alternative, more sustainable protein feeds are necessary to meet the increasing needs, and to decrease the environmental footprint of animal products. Yeast Single Cell Proteins (SCP), produced locally using various agro-industrial by-product streams, have significant potential as alternative animal feed protein. Particularly, <i>Yarrowia lipolytica</i>, an oleaginous, non-pathogenic microorganism has been characterized as a “workhorse” in biotechnological studies, drawing the attention of many researchers. The present review summarizes available resources on critical issues concerning the applicability and commercialization of <i>Yarrowia lipolytica</i> as an environment-friendly protein source for animal feed. It discusses the sustainability of the yeast SCP production process, it presents the recent advances concerning <i>Yarrowia lipolytica</i> cultivation on low-cost agro-industrial by-products, and it stresses the effects on the health and welfare of productive animals due to the inclusion of <i>Yarrowia lipolytica</i> in their diet. The data presented in this study should facilitate relative research advancement and the commercialization of <i>Yarrowia lipolytica</i>’s use as an alternative protein source/supplement for animal feeds.
  • Understanding Contributions of the Creative Class to Sustainable Economic Growth in China

    Kai Zhao; Yuesheng Zhang; Jinkai Zhao; Xiaojing Li (MDPI AG, 2020-02-01)
    By investigating the direct effect of the ‘3T’s (the creative class; tolerance; technology) and their interactive effects on GDP per capita, based on the data collected from 279 cities over the period of 2002−2014, the aim of this study is to explore the practical value of the creative class theory to the sustainable economic development in China. Using econometric estimations; the results suggest that agglomeration of the creative class; improving tolerant milieu and increasing technology investment have positive explanatory powers in understanding the disparities in GDP per capita between different cities in China. However, the complementary effects on GDP per capita are only observed between the creative class and technology or technology and tolerance, while there is an interference effect between the creative class and tolerance. These findings suggest that Florida’s advocacy for generating creative competitiveness across cities and regions by building up selected amenities may be arguable, but that the creative class is substantially contributing to regional economic growth. However, the creative class may have a unique mix with other innovative elements in different contexts. Therefore, instead of extensively focusing on a ‘one-size-fits-all’ solution that praises ‘cultural consumption’, the present study suggests a ‘three-phrase theory’; which has quite generic and flexible policy focuses on different development stages.
  • Climate Change and Vegetation Evolution during the Transition from Marine Isotope Stage 5 to 4 Based on Two Typical Profiles at the Southern Chinese Loess Plateau

    Tieniu Wu; Huaqing Wu; Henry Lin; Tiantian Yang; Xiaoyang Wu; Yi Jie; Pei Tian (MDPI AG, 2020-02-01)
    The geological transitional period from the Marine Isotope Stage (MIS) 5 to 4 during the Quaternary period is a multidimensional change involving monsoon and precipitation variation, vegetation dynamics, and environmental evolution. The first loess layer (L1) and the first paleosol layer (S1) in the Chines Loess Plateau provide excellent high-resolution terrestrial sediment record for this transition. In this work, grain size (GS), CaCO<sub>3</sub> content, magnetic susceptibility (MS), and pollen composition were measured at intervals of 2-cm in two representative L1/S1 profiles in the southern Chinese Loess Plateau to reconstruct records of climatic and vegetative changes during this transition. Our results showed that, in general, the paleo-vegetation type was forest-steppe, with <i>Pinus</i> being the commonest tree, and Chenopodiaceae and <i>Artemisia</i> being common herbs in the study area. The topography had a significant impact on the distribution of paleo-vegetation. The increase of coarse particles, the decrease of magnetic susceptibility, and the rising percentage of Gramineae, <i>Artemisia</i> and Chenopodiaceae pollen, all indicated that the paleoclimate became cooler and drier over the transitional period. Besides, we identified a cool event at about 76.8 ka B.P. as revealed by grain-size curves, and in response to this event, the vegetation changed significantly but lagged several hundred years behind the grain size record. This study confirmed the cooling and drying tendency during the MIS 5 to 4 transition phase in the southern margin of the Chinese Loess Plateau. These findings shed light on the climatic change on vegetation evolution during the MIS 5 to 4 transition period.
  • Insertion of Photovoltaic Solar Systems in Technological Education Institutions in Brazil: Teacher Perceptions Concerning Contributions towards Sustainable Development

    Maurisete Fernando Ferreira; Marcos Aurélio Vasconcelos Freitas; Neilton Fidelis da Silva; Antonia Francimar da Silva; Luciana Rocha Leal da Paz (MDPI AG, 2020-02-01)
    Teaching spaces are seen as institutions presenting relevant power to promote sustainability. Thus, in addition to knowledge (re)producers, they must also assume ethical obligations to incorporate daily sustainability-oriented actions. In this context, this study evaluates faculty perceptions regarding contributions to the teaching−learning process and the diffusion of a pedagogical practice adhering to sustainability assumptions, arising from the insertion of photovoltaic solar systems in educational institutions. A study was conducted at the Rio Grande do Norte Federal Institute of Education Science and Technology, with 2.2 photovoltaic MWp distributed throughout its 21 campuses. This study investigated teacher knowledge and attitudes towards renewable energy sources in their school practice, as a way of understanding these issues and presenting propositions that will strengthen their role in daily school life. Teachers are aware of the importance of these sources, but their knowledge does not form links with their practice. Thus, the necessary connections to promote sustainability from the existence of institutional photovoltaic systems were proven insufficient. They did not support the concept, nor the adoption of pedagogical practices linked to this technology. In addition, teacher inability to bring knowledge related to renewable energies to the classroom and link them to daily student lives was also noted. The adoption of renewable energy to promote a sustainability culture demands the formation of teacher knowledge and attitudes, and this training must follow a continuous path.
  • Empirical Evaluation of the Impact of Resilience and Sustainability on Firms’ Performance

    Elia Balugani; Maria Angela Butturi; Delroy Chevers; David Parker; Bianca Rimini (MDPI AG, 2020-02-01)
    The concepts of resilience and sustainability appear multi-dimensional and correlated, depending on the context. Operational sustainability practices can enhance the resilience of a firm, and support its growth. This study aims at analyzing the impact of a sustainability strategy, measured by means of a sustainability maturity index (SMI), on the financial performance of a company. Since the SMI is strictly correlated to resilience capabilities, the performed analysis represents a first level integration of the sustainability and resilience indicators in a common framework. A data sample from 53 organizations was collected through structured interviews and analyzed to identify possible relationships between the SMI and the financial performance indexes. The analysis does not support commonly reported arguments: we show that profitability does not show a significant relationship with sustainable strategic intent. Interestingly, firm country of origin, size of the organization, and market focus, likewise, do not have a significant relationship with SMI. Arguably, multi-dimensional company performance, including both financial and non-financial measures, should be considered to assess the impact of sustainability practices. Moreover, further investigations are needed to capture firms’ nonfinancial indicators of performance that are related to sustainability and resilience, for building up a unified framework enabling trade-off analysis.
  • Understanding Rural Water Services as a Complex System: An Assessment of Key Factors as Potential Leverage Points for Improved Service Sustainability

    Nicholas Valcourt; Jeffrey Walters; Amy Javernick-Will; Karl Linden; Betelhem Hailegiorgis (MDPI AG, 2020-02-01)
    Rural water supply services worldwide consistently fail to deliver full public health impacts as intended due to a low service sustainability. This failure is increasingly attributed to weak local systems composed of social, financial and environmental factors. Current approaches in the water, sanitation and hygiene (WASH) sector for understanding and improving these systems typically focus on the strength and capacity of these factors, but not the interactions between them. We contend that these approaches overlook the inherent complexity and context-specific nature of each local system. To assess this complexity, we conducted four participatory factor mapping workshops with local stakeholders across multiple rural water contexts to identify the factors and interactions that support service sustainability. We then evaluate the potential for factors to act as strategic leverage points based on influence, dependence and feedback metrics that arise from their interactions with other factors. We find that while participants across the contexts tend to identify a common set of factors, the interactions amongst those factors and their individual ability to influence service sustainability varies considerably across contexts. These findings suggest that a more intentional focus on factor interactions in WASH systems could lead to more effective strategies for improving service sustainability.
  • Analyze the Surplus Power Entropy of Water Supply Network after an Earthquake Based on the Pressure Drive Demand (PDD) Model

    Zhuo Song; Wei Wang; Zhao Han; Donghui Ma (MDPI AG, 2020-02-01)
    It is necessary to evaluate the reliability of the water supply network, when the water supply network is damaged by an earthquake. Therefore, this paper researched the feasibility and characteristics of the surplus power entropy as the reliability index of the water supply network, and established a scheme framework for optimizing and improving the reliability of the water supply network. This paper developed a reliability evaluation model for the water supply network after an earthquake. Combined with the Monte Carlo stochastic simulation hydraulic analysis, this model is also based on the pressure-driven nodes water demand model. In the case study, the surplus power entropy method was applied to test the reliability of the model. The statistical curves of the surplus power entropy of nodes and pipe networks, the distribution of the surplus power entropy with different intensities in pipe networks, and the comparison results of three reliability improvement schemes, before and after, were obtained. The influence factors of the surplus power entropy were obtained from the data analysis. The high consistency between the surplus power entropy and flow entropy verifies the feasibility of the surplus power entropy as a reliability index. The three schemes show that the surplus power entropy index can be used as a beneficial supplement to the reliability evaluation index of the pipe network.
  • Commuting Pattern Recognition Using a Systematic Cluster Framework

    Rongrong Hong; Wenming Rao; Dong Zhou; Chengchuan An; Zhenbo Lu; Jingxin Xia (MDPI AG, 2020-02-01)
    Identifying commuting patterns for an urban network is important for various traffic applications (e.g., traffic demand management). Some studies, such as the gravity models, urban-system-model, K-means clustering, have provided insights into the investigation of commuting pattern recognition. However, commuters’ route feature is not fully considered or not accurately characterized. In this study, a systematic framework considering the route feature for commuting pattern recognition was developed for urban road networks. Three modules are included in the proposed framework. These modules were proposed based on automatic license plate recognition (ALPR) data. First, the temporal and spatial features of individual vehicles were extracted based on the trips detected by ALPR sensors, then a hierarchical clustering technique was applied to classify the detected vehicles and the ratio of commuting trips was derived. Based on the ratio of commuting trips, the temporal and spatial commuting patterns were investigated, respectively. The proposed method was finally implemented in a ring expressway of Kunshan, China. The results showed that the method can accurately extract the commuting patterns. Further investigations revealed the dynamic temporal-spatial features of commuting patterns. The findings of this study demonstrate the effectiveness of the proposed method in mining commuting patterns at urban traffic networks.
  • National-Scale Built-Environment Exposure to 100-Year Extreme Sea Levels and Sea-Level Rise

    Ryan Paulik; Scott A. Stephens; Robert G. Bell; Sanjay Wadhwa; Ben Popovich (MDPI AG, 2020-02-01)
    Coastal flooding from extreme sea levels will increase in frequency and magnitude as global climate change forces sea-level rise (SLR). Extreme sea-level events, rare in the recent past (i.e., once per century), are projected to occur at least once per year by 2050 along many of the world’s coastlines. Information showing where and how built-environment exposure increases with SLR, enables timely adaptation before damaging thresholds are reached. This study presents a first national-scale assessment of New Zealand’s built-environment exposure to future coastal flooding. We use an analytical risk model framework, “RiskScape”, to enumerate land, buildings and infrastructure exposed to a present and future 100-year extreme sea-level flood event (ESL<sub>100</sub>). We used high-resolution topographic data to assess incremental exposure to 0.1 m SLR increases. This approach detects variable rates in the potential magnitude and timing of future flood exposure in response to SLR over decadal scales. National built-land and asset exposure to ESL<sub>100</sub> flooding doubles with less than 1 m SLR, indicating low-lying areas are likely to experience rapid exposure increases from modest increases in SLR expected within the next few decades. This highlights an urgent need for national and regional actions to anticipate and adaptively plan to reduce future socio-economic impacts arising from flood exposure to extreme sea-levels and SLR.
  • Study on the Influence of Air Tightness of the Building Envelope on Indoor Particle Concentration

    Liang Yu; Kang Ning; Weikuan Wang; Huiyu Guo; Jia Ji (MDPI AG, 2020-02-01)
    In order to grasp the building palisade structure tightness of indoor particulate matter mass concentration based on the particle penetration mechanism and settlement characteristics, this article analyzes the measurements of two different types of building air tightness of a Shenyang university office building in terms of indoor and outdoor particulate matter mass concentration levels from 2016-1-09 to 1-22, 2016-7-18 to 8-03, and 2017-2-28 to 3-13. The building outside the closed window that had no indoor source condition, the indoor office building and outdoor particle mass concentration, and the aperture size and shape of the envelope were analyzed to carry on the numerical simulation research by Fluent software, which was then analyzed; the results reveal that the measuring point of the I/O ratio is less than point B of the I/O ratio, measurement points of A linear regression fitting degree is lower than the fit of the measuring point B, and the causes for the measuring point A tightness (level 8) is superior to the measuring point B (level 4). When the gap height h is greater than 0.5 mm, the penetration rate of particles within the range of 0.25−2.5 μm particle size is close to 1. In different gap depths, the penetration rate of particles within the range of 0.1−1 μm particle size was close to 1. In diverse pressure difference, the 0.25−2.5 μm particles within the scope of penetration rate<i> P </i>is close to 1, the gap on both sides of the differential value ΔP; the greater the particle, the higher penetration rate. The larger the right-angle number of gap n, the lower the penetration rate of particles. The L-shaped gap and U-shaped gap have significantly better barrier effects in larger and smaller particles than the rectangular gap. The research results in this paper can help people understand and effectively control the influence of outdoor particles on the indoor air quality and provide reference data for the prediction of indoor particle mass concentration in buildings, which has theoretical basis and practical significance.
  • Does the Revised <i>Hukou</i> System Facilitate or Restrain the Short-Term Labor Inflows into Chinese Cities?

    Hao Cui; Joonmo Cho (MDPI AG, 2020-02-01)
    According to previous studies, the Chinese revised Hukou system has not been proven to be effective in the short-term movement of the rural labor force or in controlling urban populations. In this study, we address and analyze the self-selection problem from the perspective of inflows of short-term migration from the rural labor force and the endogeneity problem in the adoption of the revised <i>Hukou</i> system, based on the data from China Family Panel Studies (CFPS). The study shows that the revised <i>Hukou</i> system adopted by Chinese local governments was significantly efficient and harmed the short-term migration decisions of the rural labor force.

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