Soft sensing of water depth in combined sewers using LSTM neural networks with missing observations

Information and communication technologies combined with in-situ sensors are increasingly being used in the management of urban drainage systems. The large amount of data collected in these systems can be used to train a data-driven soft sensor, which can supplement the physical sensor. Artificial Neural Networks have long been used for time series forecasting given their ability to recognize patterns in the data. Long Short-Term Memory (LSTM) neural networks are equipped with memory gates to help them learn time dependencies in a data series and have been proven to outperform other type of networks in predicting water levels in urban drainage systems. When used for soft sensing, neural networks typically receive antecedent observations as input, as these are good predictors of the current value. However, the antecedent observations may be missing due to transmission errors or deemed anomalous due to errors that are not easily explained. This study quantifies and compares the predictive accuracy of LSTM networks in scenarios of limited or missing antecedent observations. We applied these scenarios to an 11-month observation series from a combined sewer overflow chamber in Copenhagen, Denmark. We observed that i) LSTM predictions generally displayed large variability across training runs, which may be reduced by improving the selection of hyperparameters (non-trainable parameters); ii) when the most recent observations were known, adding information on the past did not improve the prediction accuracy; iii) when gaps were introduced in the antecedent water depth observations, LSTM networks were capable of compensating for the missing information with the other available input features (time of the day and rainfall intensity); iv) LSTM networks trained without antecedent water depth observations yielded larger prediction errors, but still comparable with other scenarios and captured both dry and wet weather behaviors. Therefore, we concluded that LSTM neural network may be trained to act as soft sensors in urban drainage systems even when observations from the physical sensors are missing.     

Variation in susceptibility to insecticides and synergistic effect of enzyme inhibitors in Pakistani strains of Trogoderma granarium

Trogoderma granarium is an important quarantine insect pest of economic importance worldwide. Insecticides are heavily used against this pest that can reduce its susceptibility levels, and if left unchecked, this could lead to misuse of insecticides. Here, the susceptibility of five field strains of T. granarium in comparison to a reference strain (Lab-TG) was determined against pirimiphos-methyl, permethrin and spinosad using dose-mortality bioassays. Based on lethal dose (LD₅₀ and LD₉₉) values, the Lab-TG strain was the most susceptible to all the insecticides in comparison to the field strains. In the case of field strains, LD₅₀ values varied from: 17.68–31.97 mg/kg for pirimiphos-methyl, 20.50–42.47 mg/kg for permethrin, and 1.34–5.00 mg/kg for spinosad. Whereas LD₉₉ values for pirimiphos-methyl, permethrin and spinosad of field strains varied from 409.07 to 730.24 mg/kg, 374.24–949.48 mg/kg, and 11.41–72.25 mg/kg, respectively. The resistance ratios (RR) at LD₅₀ and LD₉₉ levels were in the range of 13.71–24.78 and 39.33–70.21 fold for pirimiphos-methyl; 13.49–27.94 and 37.31–94.66 fold for permethrin; 2.35–8.77 and 3.37–21.31 fold for spinosad, respectively. Considering the overall results, spinosad proved to be the most toxic insecticide to the laboratory and field strains of T. granarium when compared with toxicity of pirimiphos-methyl or permethrin. Insecticidal bioassays implementing enzyme inhibitors revealed no effect on synergizing the toxicity of all the insecticides in the Lab-TG strain; however, enzyme inhibitors significantly synergized toxicity of pirimiphos-methyl in all the field strain suggesting the major involvement of metabolic mechanism associated with pirimiphos-methyl resistance. The study demonstrates variation in susceptibility to insecticides in T. granarium strains. The results might be helpful for monitoring future variation in susceptibility to insecticides in T. granarium and for setting field rates.     

Research on economic benefits of multi-city logistics development based on data-driven analysis

This study aims to measure the logistics economic efficiency of major first-tier cities in China and propose the interactive development plan of the green logistics industry based on the division of the urban agglomeration. In this study, the evaluation system for the logistics input and economic output of urban agglomerations is firstly established based on data-driven analytics, and a green logistics economic efficiency model using the dataset from 2008 to 2017 is constructed to estimate the input–output efficiency, development trend, and spatial differentiation of urban agglomerations comprehensively. Finally, the Shapley value method is adopted to obtain the specific distribution plan of logistics investment. The results show that the logistics economic efficiency of the 9 major urban agglomerations is all greater than 1 under the constant returns-to-scale (CRS) hypothesis while the average logistics economic efficiency of Pearl River Delta region, Chengdu-Chongqing region, and Shandong Peninsula region is significantly less than 1 under the medium returns-to-scale (MRS) hypothesis. The comprehensive input–output efficiency of five out of 9 major Chinese urban agglomerations showed a downward trend, with the highest declining rate of 5.9% in the Yangtze River Delta urban agglomeration. The urban agglomeration with the highest increase rate in input–output efficiency from 2013 to 2017 is the Chengdu-Chongqing region, which reached 3.97%.     

Crowdsourcing the perceived urban built environment via social media: The case of underutilized land

Crowdsourcing the public’s perceptions of the built environment in real time enables more responsive and agile infrastructure and land use planning. Social media has emerged to be an effective platform for citizens, engineers, and planners to communicate opinions and feelings transparently. However, a comprehensive terminological resource of the perceived built environment (BE) for consistent data collection and a specified analytical framework are still lacking, particularly for different underutilized land issues. To fill this knowledge gap, we demonstrate a BE-specific term construction and expansion method specifically for collecting Twitter data and propose a Geo-Topic-Sentiment analytical framework for retrieving and analyzing relevant tweets. We conduct a demonstrative study on un(der)utilized land-related BE terms across ten metropolitan statistical areas in the U.S. Findings reveal spatial variations in contents and sentiments about underutilized land environments, and more localized efforts may be required to address specific land use issues across different urban contexts. The research demonstrates Twitter as a useful platform in crowdsourcing perceived BE and sentiments at fine temporal and spatial scales in a timely manner. It contributes to engineering informatics by investigating the role of social media in environmental planning and proposing integrated domain-specific data analytic approaches for engineering practices.     

Impact of Lake Michigan water level rise on complex bidirectional flow in the Chicago Area Waterway System (CAWS)

In the past decade, continuously rising water levels in Lake Michigan have been threatening lakefront areas, especially in metropolitan regions like the Greater Chicago area. This provides the motivation to analyze the impact that high lake levels have on the Chicago Area Waterway System (CAWS). As the only primary free connection between the CAWS and Lake Michigan, the Calumet Area waterway subsystem plays a key and unique role. In this work, a numerical model covering the Calumet subsystem and having Lake Michigan as a boundary condition, is set up, calibrated, and validated using limited field observations. It is found that the Calumet subsystem has become bidirectional, where both discharge and flow directions are controlled by lake levels. When lake levels are below −0.15 m (-0.5 ft, Chicago City Datum, CCD), the discharge in the Grand Calumet River is around zero, with water flowing along its east branch towards Indiana. When lake levels are above +0.46 m (+1.5 ft, CCD), the flow reverses direction and drains west into Illinois. In 2020, the mean lake-level was at +1.07 m (+3.5 ft, CCD), and the base discharge in the Grand Calumet River was approximately 8.5 m³/s (300 ft³/s). The higher Lake Michigan’s level is, the larger the discharge would be into Illinois. Potential impact of this extra discharge on Lake Michigan Diversion Accounting (LMDA) of the State of Illinois and flood management in the Chicago Sanitary and Ship Canal (CSSC), is analyzed; while the nature of the bidirectional flows is characterized with the intent of shedding light on this complex phenomenon.     

A comparative assessment of local municipal food policy integration in the Netherlands

ABSTRACT

Local governments around the world increasingly engage in food governance, aiming to address food system challenges such as obesity, food waste, or food insecurity. However, the extent to which municipalities have actually integrated food across their policies remains unknown. This study addresses this question by conducting a medium-n systematic content analysis of local food policy outputs of 31 Dutch municipalities. Policy outputs were coded for the food goals and instruments adopted by local governments. Our analysis shows that most municipalities integrate food to a limited extent only, predominantly addressing health and local food production or consumption. Furthermore, municipalities seem hesitant to use coercive instruments and predominantly employ informative and organizational instruments. Nonetheless, a small number of municipalities have developed more holistic approaches to address food challenges. These cities may prove to be a leading group in the development of system-based approaches in Dutch local food policy.     

Building urban resilience with nature-based solutions: How can urban planning contribute?

Cities face increasing environmental, social and economic challenges that together threaten the resilience of urban areas and the residents who live and work there. These challenges include chronic stresses and acute shocks, amplified by climate change impacts. Nature-based solutions have emerged as a concept for integrating ecosystem-based approaches to address a range of societal challenges. Nature-based solutions directly address and contribute to increased urban resilience. However, implementing nature-based solutions is inherently complex, given the range of ecosystem services, their multi-functionality and the trade-offs between functions, and across temporal and spatial scales. Urban planning can play a substantial role to support the implementation of nature-based solutions and to manage trade-offs and conflicts, as well as how social equity dimensions are considered. This paper presents a framework that guides the application of urban planning to nature-based solutions’ implementation, by addressing key trade-offs across temporal, spatial, functional and social equity aspects. The framework highlights the key questions, and the supporting information required to address these questions, to underpin the inclusion of nature-based solutions for urban resilience. We find that while urban planning can contribute substantially, there are continuing gaps in how the inherently anthropocentric urban planning processes can give voice to non-human nature.     

河涌污染治理生态恢复技术的研究进展

随着经济的快速发展,大量污染物排入河涌导致河涌水体污染问题日趋严重。采取有效的技术措施治理河涌污染势在必行。结合近年来国内外河涌治理的研究成果,综述了河涌治理中生态恢复技术的原理和特点,并指出今后研究方向。     

新世纪之交的德国城市设计——百年思想的演进与更替

德国城市设计学科的发展对世界产生了广泛而深远的影响,本文对德国当代城市设计面临的挑战与对策进行了系统梳理。文章首先对现代城市设计早期德国的城市设计内涵的基本认识进行了总结,在此基础上回顾了现代主义兴起、东西德分裂条件下德国各个时期城市设计发展的基本特征。在此基础上,分三个方面对德国当代城市设计进行了梳理:1)重塑美学和历史在城市设计中的合法地位,帮助确立当代全新的城市设计范式;2)社会导向的福利国家模式应对全球化影响的多种城市设计举措;3)落实一系列可持续城市发展的策略。文章最后概括了德国城市设计发展经验对于我国的借鉴意义。     

移动定位大数据支持建成环境规划设计的途径和方法

移动定位大数据包括手机信令数 据、移动互联网LBS数据等类型,是表示个 体活动时空特征的轨迹数据。在移动定位 大数据中依据轨迹点的时空特征规律能识 别出个体活动的居住、工作、游憩等特征 点,计算上述活动的空间分布特征,进而获 得居住、工作、游憩等功能之间联系的流向 和流量特征,获得传统数据无法反映的城 市功能空间分布以及城市功能联系的时空 特征。由此,移动定位大数据支持建成环境 规划设计有密度出发和联系出发两种应用途 径。联系出发的途径能支持区域城市关联、 职住空间关系、城市中心体系、设施服务水 平等方向;密度出发的应用途径能支持城 市人口规模、街道活力分析等方向。移动定 位大数据测算居民活动特征还只是一种推 测,在应用方法上要避免“黑箱”方式,对移 动定位大数据测算结果一定要结合传统数 据进行校核,提高可靠性。