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Amid China's rapid economic expansion, the country's industrial solid waste (ISW) problem is escalating. As each sector generates distinct types of ISW, a multi-indicator assessment of each sector is essential to address China's New Solid Waste Policy. To investigate the ISW situation of each sector and perform a comprehensive assessment, we formulate an industrial solid waste ecological analysis framework based on ISW generation and ISW flow in the sector. Various indicators (i.e., solid waste utilization coefficient, solid waste threat coefficient, and solid waste threat intensity) are employed to assess the utilization of solid waste generated for each sector, as well as the threat of solid waste originating in each sector to society. Ecological network analysis probes the interrelationships between diverse sectors. Taking Shanghai in 2017 as an example, the study indicates that some sectors (e.g., production and supply of electric power and heat power (EH) and metal smelting and rolling processing sector (MS)) exhibit higher direct ISW generation and the direct industrial solid waste value-added coefficient (SVAC) for common industrial solid waste (CISW). Specifically, the direct CISW generation of EH and MS is 539.21Mt and 277.00Mt respectively. The direct SVAC of EH and MS is 157.06kg/103RMB and 126.27kg/103RMB respectively. These sectors should prioritize reducing emissions at the source. Additionally, the threats to society from various sectors are relatively insignificant for the CISW, while for the hazardous waste (HW), all sectors pose a considerable threat to Shanghai's society. Moreover, some sectors (e.g., mining industry) exhibit the highest mutualism relationships in the CISW and the HW. Enhancing mining sector technologies is a vital strategy for mitigating ISW sources. Specifically, MI has 9 pairs of mutualism relationships in the CISW and 8 pairs in the HW. These insights will provide empirical evidence for tackling the ISW problem in Shanghai. [ABSTRACT FROM AUTHOR]

Background: To investigate the prevalence and risk factors of refractive astigmatism (RA) and corneal astigmatism (CA) in preschool children and school-aged children in Shanghai, China. Methods: In this school-based, cross-sectional study, 4–15 years old children across three learning stages of kindergarten, primary school, and junior high school underwent noncycloplegic autorefraction and completed comprehensive questionnaires involving time spent on daily homework and outdoor activities. Data from the right eyes were analysed. Results: Overall, 7084 children (mean ± standard deviation (SD) of age: 8.08 ± 3.11 years) were included, and the prevalence rates of RA/CA (≤ − 1.0 D) in children were 15.8%/64% in kindergartens, 16.5%/65% in primary schools, and 32.8%/76.9% in junior high schools. The magnitude and prevalence of RA and CA all increased with age or with learning stage (all P < 0.001). The presence of RA was associated with more myopic spherical power (odds ratio (OR) 0.956, P = 0.021), junior high school (OR 1.973, P < 0.001), longer homework time on weekdays (OR 1.074, P = 0.029), and shorter outdoor activity time on weekends (odds ratio 0.929, P = 0.013). Conclusion: In the wide age range of 4 to 15 years, the magnitude and prevalence of RA and CA increased with the learning stage, and these increases mainly began at the primary school stage. Factors, including longer homework time and shorter outdoor time were correlated with the presence of RA. [ABSTRACT FROM AUTHOR]

This paper presents an analytical model to investigate backfill grout diffusion behind tunnel segmental lining, in which the backfill grout is taken as a Bingham fluid. The analytical model of grout diffusion is derived based on force–equilibrium principle, Darcy's law, and the law of momentum conservation of the grout. Time‐dependent grout diffusion pressure and distance are highlighted in the model. The proposed grout diffusion model is applied in two field cases: Metro Lines No. 9 and No. 4 in Shanghai City. The results show that the proposed model agrees well with the measured grout diffusion distance in the field. Parametric studies are then conducted, implying that grout diffusion distance along the radial direction of tunnel lining is proportional to either hydraulic conductivity or initial grout pressure, whereas it is in inverse proportion to the yield stress of backfill grout. The distributions of initial grout pressure exert key influences on the grout diffusion distance and grout diffusion pressure behind tunnel segment lining. [ABSTRACT FROM AUTHOR]

Due to its capability to reduce fuel consumption and increase energy efficiency, the combined cooling, heating, and power (CCHP) system has obtained great concern during the last decade. A large number of deterministic and stochastic optimization models were proposed for supporting the operation management of the CCHP system, but few studies noticed that users' demands in the real world may be subjected to twofold randomness with incomplete or uncertain information. In this study, a birandom chance-constrained linear programming (BCCLP) model is developed for identifying optimal operation strategies under random uncertainties. Compared with traditional stochastic programming models, the BCCLP model made the improvement through describing the energy demands as the birandom variables firstly, instead of traditional random variables. This way effectively avoided potential imbalance between energy supply and demand caused by oversimplified expression of uncertain parameters. A gas-fired CCHP system of a hotel in Shanghai, China, was used as a study case for demonstration. A variety of operation strategies are obtained under specific constraints-satisfaction conditions. It is concluded that the BCCLP model was capable of generating the cost-effective operation strategies and evaluating the tradeoffs between system economy and reliability. The influence imposed by some critical parameters on the system performance was examined through the sensitivity analysis, which provided the important guidance to the design and operational management of other similar CCHP systems in the future. [ABSTRACT FROM AUTHOR]

Flooding hazards caused by heavy rainfall in Shanghai have been reported extensively in the last 15 years. Geologically, Shanghai is sensitive to flooding hazards due to low-lying ground caused by land subsidence. Climatically, Shanghai is in the East Asia monsoon area and frequently experiences torrential rains. In this study, data from fifty-four pluvial flooding events between 2001 and 2015 were collected and analysed. The influence factors contributing to pluvial flooding are evaluated, and recommendations for protective measures are presented. The pluvial flooding prevention capacity in Shanghai is controlled by rain water storage and discharge capacity, which is associated with the sewer network, pumping stations and its sluice and pumping gates. Within the last three decades, the number of local torrential rainfall events and short-duration torrential rains has increased annually. However, the rain water storage capacity has decreased dramatically and the rain water discharge capacity has become limited during this period. In an extreme case, the discharge function of the sewer network was even temporarily lost because of flooding of the distributaries of the Huangpu River. Thus, in order to prevent flooding hazards caused by heavy rain, it is suggested that a large sluice and pumping station between the Huangpu River and the Yangtze River estuary is constructed in the near future, considering the continuous subsidence of the city and the ongoing rising sea levels. [ABSTRACT FROM AUTHOR]

The Quaternary deposits in Shanghai primarily consists of a phreatic aquifer group (Aq0) and five artesian aquifers (AqI-AqV) that are separated by six aquitards (AdI-AdVI). In the basin of the Huangpu River, the first artesian aquifer (AqI) is connected to the second artesian aquifer (AqII), forming a 50-m-thick artesian aquifer with a very high groundwater level. The highway tunnels under the Huangpu River of Shanghai are constructed at a maximum depth up to 45 m, within the artesian aquifer. These tunnels are lined with precast reinforced concrete segments without a second lining. Under high water pressure, it is difficult for the single shell linings to achieve water tightness. Different degrees of groundwater leakage have been observed in road tunnels under the Huangpu River. The tunnels constructed before the 1990s have had very serious groundwater leakage (e.g., >1 L/m/day), and the recently constructed tunnels have leaked less than 0.1 L/m/day. The factors influencing groundwater leakage include depth below groundwater level, differential settlement of the tunnel, and applied waterproof technologies. The increase in depth leads to a significant increase in groundwater leakage. The differential settlement causes gaps to open and offset between segments, as well as cracking of segments, which can also induce groundwater leakage. According to the analysis of recorded data, the number of leaking points tends to increase with the curvature of the settlement curve. In addition, inappropriate waterproofing materials and poor waterproofing design will also lead to groundwater leakage. Groundwater leakage causes deterioration of the structure, aging of the installations in the tunnels (e.g., facilities and pavements), as well as discomfort for users of the tunnels and adverse environmental impacts. Furthermore, groundwater leakage also causes structural deformation of the tunnel itself, leading to further leakage and hazards. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The quaternary deposit of Shanghai is composed of an alternated multi-aquifer-aquitard system (MAAS) consisting of a sequence of aquitards laid over aquifers one by one. In the MAAS, any drawdown of groundwater head in an aquifer may cause consolidation of the overburden aquitard. When underground structures penetrate those aquifers, groundwater seepage path changes and drawdown occurs at the side characterized by the lower hydraulic potential along the flow direction (hereafter refers as to the lower side). This drawdown may cause additional subsidence at the lower side and unbalanced load between the two sides of the underground structure. In order to evaluate the cutoff effect of an underground structure on groundwater seepage in a MAAS representative of the underground of the city of Shanghai, a numerical analysis based on a groundwater flow model has been carried out. The simulated results have shown that underground structures which cut off groundwater flow locally change both magnitude and direction of the flow velocity field. The induced changes in the groundwater field are highly sensitive to the penetration depth and width of the underground structure. Design recommendations for underground structures in aquifers belonging to a MAAS are also presented, which has not yet been considered in the engineering practice of Shanghai. [ABSTRACT FROM AUTHOR]

Since 1980, land subsidence has accelerated and groundwater levels have decreased in the centre of Shanghai, although the net withdrawn volume of groundwater has not increased. Theoretical analysis of the monitored data shows that the decrease in the groundwater level is the primary reason for the observed land subsidence. Meanwhile, the net withdrawn volume of groundwater in the urban centre of Shanghai has not increased during this period. Many underground structures have been constructed in the multi-aquifer-aquitard system of Shanghai since 1980. This paper discusses the factors related to the development of land subsidence during the process of urbanisation in Shanghai during the past 30 years. These factors include additional load during and after structure construction, the cut-off and/or partial cut-off effect of underground structures in aquifers, the decrease in the groundwater level due to leakage of underground structures and the reduction in recharge of groundwater from the surroundings. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a case history of an earth pressure balance (EPB) shield tunneling constructed in a close distance near constructed underground structures in soft deposit of Shanghai. In order to protect existing underground structures, field observation was carried out, including reinforcement stress of interior structure and lateral displacement of the diaphragm wall. Throughout the shield tunneling construction, various countermeasures were adopted based on field observation feedback to minimize adverse environmental influences. The maximum cumulative lateral displacement of the diaphragm wall is about 11mm. The maximum stress of reinforcement is 18.6MPa, much less than the design value of steel tensile strength. These results and countermeasures are useful for engineers and technicians to select serviceable machine operation parameters and reduce environmental impacts during shield tunneling construction. [Copyright &y& Elsevier]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Shanghai Administrative Region (SAR) is located on the deltaic deposit of the Yangtze River. The bed rock under SAR is generally buried in the depth of 200 m to 300 m except for several massifs, where the bed rock is exposed to the ground surface. The Quaternary deposit in Shanghai is soft sediment. The variation of palaeoclimate influenced the sea level and resulted in a very complicated sedimentary environment. The Quaternary deposit in SAR is composed of an alternated multi-aquifer-aquitard system (MAAS). The groundwater system is composed of one artesian aquifer and five confined aquifer layers with very high groundwater pressure head. The MAAS was formed mainly within the warm geological era updated to 2.6 million years ago. Between two aquifers, there is an aquitard which is composed of soft clayey soil formed mainly within the cold era. The aquitards are composed of very soft clayey silt with very high compressibility and humus content. The humus material was transformed into methane gas under a long-term geological process. With the development of economy, the infrastructures were (or are being) constructed in the top shallow soft clayey deposit, aquifer I and aquifer II. In SAR, the following geohazards occurred or possibly occur during the construction and maintenance of infrastructures: i) quicksand and piping hazards; ii) pumping-induced hazards and recharge-cutoff hazards; iii) long-term settlement due to the seasonal fluctuation of groundwater level; and iv) geohazards of methane gas. [Copyright &y& Elsevier]

[Display omitted] • The abnormal change in weather elements under climate change were identified. • The extreme value of user demand under extreme weather was estimated. • The damage to operation efficiency of gas turbine under climate change was examined. • The operation optimization strategies adapted to climate change were proposed. • It is expected to be a demonstration for rational operation of other CCHP systems. The operation optimization of a CCHP system of a hospital in Shanghai, China, was used as a study case for demonstrating the feasibility and applicability of the dynamic interactive model (as introduced in Part I of this article). This model comprehensively considered the impact of climate change on users' demand and power generation of equipment, coupling these aspects to the operational optimization of CCHP system. The obtained results demonstrated that the increase of temperature would pose a large influence on user demand and impair the operation efficiency of gas turbine. Moreover, the implementation of energy cascade utilization mechanism and tiered electricity price would also affect operation schedule of a CCHP system. Compared with traditional optimization model, the developed dynamic interactive model could effectively overcome the problem of insufficient cooling and excessive heating in both summer and winter seasons under climate change, and achieve stable energy supply. Overall, the proposed model could help improve system economy, realize efficient utilization of energy and enhance energy-supply stability, which is of high value for supporting long-term sustainable management of energy supply systems under climate change. [ABSTRACT FROM AUTHOR]

• Explore the relationship between industrial solid waste and socioeconomic. • Analyze the flow relationships among different sectors of industrial solid waste. • Determine the industrial solid waste discharge responsibility for each sector. • Identify the key sectors for industrial solid waste discharge. • Simulate industrial solid waste reduction measures. Rapid economic development inevitably leads to the discharge of a large amount of common industrial solid waste (CISW), which not only pollutes the environment but also restricts economic development in turn. In this study, a dynamic common industrial solid waste (DCISW) model is developed to analyze the retrospectively CISW development in Shanghai from 2000 to 2017 and simulate prospectively multi-perspective emission reduction measures. Specifically, the dynamic linkages between CISW and socio-economics are established at both the systematic and sectoral levels through input–output analysis, ecological network analysis, and related socio-economic indicators. Abatement measure simulations are conducted using RAS and other methods. The findings reveal that the growth of CISW in Shanghai is closely related to its fast-growing economy. The Others sector (OS) receives the most CISW from other sectors, while the Mining industry (MI) sends the most CISW to others. From production-based, consumption-based, and income-based perspectives, Chemical Products (CP) consistently remain the largest contributors. For the proposed waste generation intensity (WGI) indicator, the Mining industry (MI) is regarded as the main sector in all three perspectives. Moreover, the MI consistently emerges as the key sector of the system. CISW simulations indicate that improving the MI emission technology and increasing the MI output value will be top priorities for CISW emission reduction in Shanghai. This study is expected to provide scientific support to address the CISW problem in Shanghai and other similar fast-growing metropolises. [ABSTRACT FROM AUTHOR]

Land subsidence is a severe geo-hazard in coastal regions and represents a great threat to infrastructure. Based on long-term measurement data, including that for deep compaction from vertical multipoint extensometers, land subsidence and infrastructural settlement from leveling surveys, groundwater levels in multiple confined aquifers, and hydrogeological conditions, this study investigates the effects of groundwater exploitation and recharge on land subsidence and the settlement of infrastructure in Shanghai, China. Further, groundwater exploitation and the consequent responses of piezometric heads in the multiple confined aquifers of Shanghai soft deposits are discussed. Subsequently, regional land subsidence, local deep-soil deformation, and infrastructural settlement are analyzed in terms of groundwater exploitation. It is found that the subsidence pattern is related to the trend of groundwater exploitation and the variation of piezometric heads in the aquifers, which can be roughly divided into three phases. Subsidence funnels could occur, and could be interpreted according to the differences in groundwater exploitation intensity and the spatial variability of lithology. Since the towers of Nanpu Bridge are located within the area of the subsidence funnel, this could be the main reason for the differential settlement of the bridge. • Responses of piezometric-head to groundwater exploitation and recharge in deep confined aquifers are investigated. • Annual land subsidence is discussed in association with the piezometric-head in deep confined aquifers. • Pier settlements of the Nanpu Bridge in urban and suburban are comparatively analyzed. • Measured deep soil deformations are presented to interpret the land subsidence and infrastructure settlements. [ABSTRACT FROM AUTHOR]

Purpose: To compare the long-term refractive effects of small-incision lenticule extraction (SMILE) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) on the correction of high myopia and astigmatism. Setting: The Eye and ENT Hospital of Fudan University, Shanghai, China. Design: Retrospective case series. Methods: Patients had SMILE or FS-LASIK for high myopia. Subgroup analyses of high myopia (-6.00 to -8.75 diopters [D]) and extremely high myopia (>=-9.00 D) were performed. The main outcome measure was refractive predictability, compared between SMILE and FS-LASIK groups. Secondary outcomes included efficacy, safety, and residual astigmatism. Results: This study included 121 patients (121 eyes: 75 in the SMILE group and 46 in the FS-LASIK group). No differences were found in terms of refractive predictability between SMILE and FS-LASIK in eyes with high myopia: 56% vs 58.7% achieved +/- 0.50 D of attempted correction (P =.771) and 81.3% vs 76.1% achieved +/- 1.00 D of attempted correction (P =.489). Efficacy indices of the SMILE and FS-LASIK groups were 1.02 +/- 0.24 and 1.03 +/- 0.24 (P =.742), respectively; safety indices were 1.23 +/- 0.22 and 1.20 +/- 0.24 (P =.324), respectively. Logarithm of the minimum angle of resolution uncorrected distance visual acuity and spherical equivalent in the high myopia subgroup were better than in the extremely high myopia subgroup after both SMILE and FS-LASIK (P <.01). Conclusions: SMILE and FS-LASIK were both effective in correcting high myopia and myopic astigmatism. However, both techniques may require further nomogram adjustments when treating eyes with extremely high myopia. [ABSTRACT FROM AUTHOR]

This paper presents a laboratory evaluation on the strength behavior of cement–clay admixture improved by polypropylene fiber. Waste polymer textile bags are harmful to the environment and sustainable means to reuse them are urgently being sought. A novel method to recycle these waste polymer textile bags is applying them in soft soil improvement projects, such as compacted-pavement base/subbases. In order to verify the effectiveness of fiber bundles used in soil mixing, a series of laboratory investigation are conducted on fiber-reinforced cement-improved soft Shanghai clay. In the tests, two types of polymer fibers were employed; the first one is monofilament polypropylene fiber and the other is fiber bundles split from polymer textile bags. The tests were conducted using unconfined compressive strength (UCS) test after the specimen of fiber–soil–cement admixture were cured for some period. The results show that fiber additive can significantly improve the strength and ductility of the cement treated Shanghai clay. The UCS of fiber–soil–cement admixture is related to both content and length of fiber. Both two kinds of fiber-reinforced cement clay reached their peak strength at fiber content of 0.5%. UCS will slowly reverse if the fiber content continues to increase. Even though the polypropylene fiber works better than the fiber bundles, the difference is less than 5%. These results indicate that the fiber bundles split from polymer bags can be used as the reinforcement in soil mixing, thus providing a novel approach to treat waste polymer textile bags. [ABSTRACT FROM AUTHOR]