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Review of peri-urban agriculture as a regional ecosystem service

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Geography and Sustainability 2023年第3期4卷 244-254页

作者： Setyardi Pratika Mulya Heru Purboyo Hidayat Putro Delik Hudalah urban and Regional Planning Study program School of ArchitecturePlanningand Policy DevelopmentBandung Institute of TechnologyBandung 40132Indonesia Department of Soil Science and Land Resources Faculty of AgricultureBogor Agricultural UniversityBogor 16680Indonesia

The peri-urban area possesses mixed characteristics of rural and urban areas,i.e.,agricultural,and built-up *** review explains various themes and concepts of peri-urban areas and the importance of peri-urban agriculture(PUA)as an ecosystem service(ES)for their surrounding *** methodological approach is a systematic literature search and explanatory review of books and journal *** focus of the discussion is as follows:(1)quantification of review results,(2)urbanization pressures,peri-urban,and governance,(3)two different concepts about the peri-urban area,(4)protection of PUA and their resilience,and(5)role of PUA in providing ESs to other *** review shows that PUA is more crucial in urban areas than in rural areas in terms of food supply,ecology and biodiversity preservation,disaster mitigation,and *** of the primary causes of PUA loss is massive urban expansion,which entails the conversion of agricultural land in peri-urban areas into built-up ***,we suggest that every country should develop a peri-urban management *** argue that sociocultural biases in PUA have resulted in many institutional constraints on peri-urban management being incorporated within existing political and regulatory frameworks,including planning practices and longstanding laws and regulations.

关键词： Farming Impact Regulation urbanization urban-rural interaction

The scarab gut： A potential bioreactor for bio-fuel production

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Insect Science 2010年第3期17卷 175-183页

作者： Sheng-Wei Huang Hong-Yu Zhang Sean Marshall Trevor A. Jackson State Key Laboratory of Agricultural Microbiology Institute of Urban and Horticultural Pests and Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and Technology Huazhong Agricultural University Wuhan China Biocontrol Biosecurity and Bioprocessing AgResearch Limited Christchurch New Zealand

Cellulose and hemicelluloses are the most prevalent sources of carbon in nature. Currently many approaches employ micro-organisms and their enzyme products to degrade plant feedstocks for production of bioenergy. Scarab larvae are one such model. They consume celluloses from a variety of sources including plant roots, soil organic matter and decaying wood, and are able to extract nutrients and energy from these sources. In this paper, we review the physicochemical properties of the scarab larval gut, the diversity and digestive role that microflora play in the scarab gut and discuss the potential for applying these digestive processes in bioreactors for improving bio-fuel production. Scarab larvae are characterised by their highly alkaline midgut which is dominated by serine proteinase enzymes, and a modified hindgut which harbors the majority of the intestinal microbiota under anaerobic conditions. Evidence suggests that digestion of recalcitrant organic matter in scarab larvae likely results from a combination of endogenous gut proteinases and cellulolytic enzymes produced by symbiotic micro-organisms. Most of the easily digestible proteins are mobilized and absorbed in the midgut by endogenous proteinases. The hindgut contents of scarab larvae are characterized by high concentrations of volatile fatty acids, the presence of fermenting bacteria, and typical anaerobic activities, such as methanogenesis. The hindgut typically contains a wide diversity of micro-organisms, some of which appear to be obligate symbionts with cellulolytic potential. As a result, the scarab larval gut can be regarded as a small bioreactor resembling the rumen of sheep or cattle, where solid food particles composed of cellulose, hemicellulose, pectin and polysaccharides are degraded through enzymatic and fermentation processes. Together these observations suggest scarab larvae have potential to assist the bio-fuel industry by providing new sources of （hemi）cellulolytic bacteria and bacteri

关键词： bio-fuel bioreactor cellulolytic enzymes microflora Scarabaeidae

Analysis of load and adaptability of disc cutters during shield tunneling in soft-hard varied strata

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Frontiers of Structural and Civil Engineering 2023年第4期17卷 533-545页

作者： Fengwei YANG Weilin SU Yi YANG Zhiguo CAO Yellow River Engineering Consulting Co. Ltd.Zhengzhou 450003China Key Laboratory of Water management and Water Security for Yellow River Basin Ministry of Water ResourcesZhengzhou 450003China Key Laboratory of urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China

The disc cutters of shield machines exhibit unsatisfactory adaptability and performance during the soft–hard varied strata tunneling *** analyze the rotation state,cutting performance,and adaptability of disc cutters during shield tunneling in soft–hard varied strata,the Holmquist Johnson Cook and Federal Highway Administration constitutive models are introduced to numerically simulate the failure process of materials on the excavation face and to calculate the load of disc ***,the parameters of the models are modified based on laboratory disc cutter excavation test *** results of numerical calculation can reflect the load level and the behavior of the disc cutters during *** tangential loads of the disc cutters during the cutting of four typical soft-strata excavation face models are numerically calculated,thus providing reference values for the starting torque of the disc cutters.A greater penetration is suggested for soft-strata tunneling to allow the disc cutters to rotate smoothly and continuously as well as to guarantee a better cutting *** disc cutters in the center of the cutterhead should be specified with a lower starting torque to prevent uneven wear,rotation stagnation,cutterhead clogging,and other adverse phenomena.

关键词： shield tunneling disc cutter load laboratory excavation test numerical calculation soft-hard varied strata

Size structure of urban agglomerations in China:rationality evaluation,patterns, and implications

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Chinese Journal of Population,Resources and Environment 2018年第4期16卷 329-342页

作者： Deli Wang Jinchuan Huang Qingshan Yang Shasha Lu Yi Chen Xingliang Guan Institute of Economics Beijing Academy of Social Sciences Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences College of Geographical Science Northeast Normal University School of Economics and management Beijing Forestry University School of Architecture and urban Planning Nanjing Tech University Institute of urban Development National Academy for Mayors of China

This paper establishes a diagnostic model for assessing the rationality of size structure of urban agglomerations(UAs) in China. The model is designed to determine from a three-dimensional index including size distribution index(SDI), size compactness index(SCI), and size efficiency index(SEI). The spatio-temporal pattern of size structure involving the studied 19 UAs and its implications are explored. The results indicate that size structure of China's UAs advanced from a low rationality development stage to a moderate rationality development stage in *** them, the SDI and SEI were reasonably high, and the SCI was relatively low. Spatially, the high rationality UAs were distributed across eastern China, while the low rationality UAs were located in western China. UAs with positive size structure possessed typically a dual-or multicenter urban structure, while UAs with negative size structure usually presented as a single-center structure. The evolutionary trajectories of rationality of size structure of UAs can be summarized as four different stages. Our findings suggest that, in addition to consolidating the status of national-level UAs, the development of regional-level UAs should be promoted. Also, the fostering focus and direction should be oriented toward an UA with dual-or multicenter spatial structure.

关键词： Size structure rationality evaluation size distribution index size compactness index size efficiency index urban agglomeration China

Evaluation and Influencing Factors of urban Renewal Efficiency Based on SBM Model:A Case Study of the First Batch of Pilot Cities for urban Renewal

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Journal of Landscape Research 2023年第5期15卷 28-34,40页

作者： LIU Shen’ao ZHOU Xia School of urban Economics and management Beijing University of Civil Engineering and ArchitectureBeijing 100044China

China is already in the second half of the urbanization process,which means that the urbanization path in China needs to shift from“large-scale expansion development”in the past to“comprehensive and refined operation”.To explore how to efficiently carry out urban renewal work,from the perspective of urban renewal efficiency,the first batch of pilot cities for urban renewal released by the Ministry of Housing and urban Development in 2021 are selected as the *** the SBM model and Malmquist index are used to calculate and analyze their urban renewal *** results indicate that among the 20 pilot cities,Beijing,Tangshan,Suzhou,Tongling,and Jingdezhen are of high grade,and Hohhot,Xiamen,Huangshi,and Yinchuan are of medium grade,while the rest of the cities are of low *** regression results of the Tobit model indicate that population density,real estate investment,and regional economic development level are the main influencing factors of urban ***,constructive suggestions are proposed for urban renewal from four aspects:concept,technology,real estate,and policy.

关键词： urban renewal SBM model urban renewal efficiency

Shifts in microbial community structure and diversity in a MBR combined with worm reactors treating synthetic wastewater

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Journal of Environmental Sciences 2017年第4期29卷 246-255页

作者： Jia Liu Wei Zuo Jun Zhang Hui Li Lipin Li Yu Tian State Key Laboratory of urban Water Resource and Environment(SKLUWRE) School of Municipal and Environmental EngineeringHarbin Institute of Technology

The chemical oxygen demand（COD） and NH3-N removal, membrane fouling, sludge characteristics and microbial community structure in a membrane bioreactor（MBR） coupled with worm reactors（SSBWR） were evaluated for 210 days. The obtained results were compared to those from a conventional MBR（C-MBR） operated in parallel. The results indicated that the combined MBR（S-MBR） achieved higher COD and NH3-N removal efficiency,slower increase in membrane fouling, better sludge settleability and higher activities of the related enzymes in the activated sludge. Denaturing gradient gel electrophoresis was used to analyze the microbial community structures in the C-MBR and the S-MBR. The microbial community structure in the S-MBR was more diverse than that in the C-MBR. Additionally, the slow-growing microbes such as Saprospiraceae, Actinomyces, Frankia, Clostridium, Comamonas,Pseudomonas, Dechloromonas and Flavobacterium were enriched in the S-MBR, further accounting for the sludge reduction, membrane fouling alleviation and wastewater treatment.

关键词： Membrane bioreactor(MBR) Enzyme activities Microbial community structure

DARTS-Drone and Artificial Intelligence Reconsolidated Technological Solution for Increasing the Oil and Gas Pipeline Resilience

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International Journal of Disaster Risk Science 2022年第5期13卷 810-821页

作者： Premkumar Ravishankar Seokyon Hwang Jing Zhang Ibrahim X.Khalilullah Berna Eren-Tokgoz Department of Industrial and Systems Engineering Lamar UniversityBeaumontTX 77710USA Construction management program Lamar UniversityBeaumontTX 77710USA Department of Computer Science Lamar UniversityBeaumontTX 77710USA

The need for safe operation and effective maintenance of pipelines grows as oil and gas demand ***,it is increasingly imperative to monitor and inspect the pipeline system,detect causes contributing to developing pipeline damage,and perform preventive maintenance in a timely ***,pipeline inspection is performed at pre-determined intervals of several months,which is not sufficiently robust in terms of *** research proposes a drone and artificial intelligence reconsolidated technological solution(DARTS) by integrating drone technology and deep learning *** solution is aimed to detect the targeted potential root problems-pipes out of alignment and deterioration of pipe support system-that can cause critical pipeline failures and predict the progress of the detected problems by collecting and analyzing image data *** test results show that DARTS can be effectively used to support decision making for preventive pipeline maintenance to increase pipeline system s afety and resilience.

关键词： Artifcial intelligence Asset management Drone application Midstream industry Pipeline resilience Predictive maintenance

China's Energy Consumption Forecasting by GMDH Based Auto-Regressive Model

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Journal of Systems Science & Complexity 2017年第6期30卷 1332-1349页

作者： XIE Ling XIAO Jin HU Yi ZHAO Hengjun XIAO Yi Business School Sichuan University School of Economics and management University of Chinese Academy of Sciences School of Economics and management Sichuan Radio and TV University School of Information management Central China Normal University

It is very significant for us to predict future energy consumption accurately. As for China's energy consumption annual time series, the sample size is relatively small. This paper combines the traditional auto-regressive model with group method of data handling(GMDH) suitable for small sample prediction, and proposes a novel GMDH based auto-regressive(GAR) model. This model can finish the modeling process in self-organized manner, including finding the optimal complexity model, determining the optimal auto-regressive order and estimating model parameters. Further, four different external criteria are proposed and the corresponding four GAR models are constructed. The authors conduct empirical analysis on three energy consumption time series, including the total energy consumption, the total petroleum consumption and the total gas consumption. The results show that AS-GAR model has the best forecasting performance among the four GAR models, and it outperforms ARIMA model, BP neural network model, support vector regression model and GM(1, 1) ***, the authors give the out of sample prediction of China's energy consumption from 2014 to 2020 by AS-GAR model.

关键词： Auto-regressive model energy demand prediction GMDH small sample forecasting

Establishment and analysis of global gridded Tm-Ts relationship model

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Geodesy and Geodynamics 2016年第2期7卷 101-107页

作者： Zeying Lan Bao Zhang Yichao Geng School of management Guangdong University of TechnologyGuangzhou 510630China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Guangzhou urban Planning&Design Institute Guangzhou 510060China

In ground-based GPS meteorology, Tm is a key parameter to calculate the conversion factor that can convert the zenith wet delay（ZWD） to precipitable water vapor（PWV）. It is generally acknowledged that Tm is in an approximate linear relationship with surface temperature Ts, and the relationship presents regional variation. This paper employed sliding average method to calculate correlation coefficients and linear regression coefficients between Tm and Ts at every 2°× 2.5° grid point using Ts data from European Centre for Medium-Range Weather Forecasts（ECMWF） and Tm data from ＂GGOS Atmosphere＂, yielding the grid and bilinear interpolation-based Tm Grid model. Tested by Tm and Ts grid data, Constellation Observation System of Meteorology, Ionosphere, and Climate（COSMIC） data and radiosonde data, the Tm Grid model shows a higher accuracy relative to the Bevis Tm-Ts relationship which is widely used nowadays. The Tm Grid model will be of certain practical value in high-precision PWV calculation.

关键词： Zenith wet delay Precipitable water vapor Ground-based GPS meteorology Weighted mean temperature Gridded Tm-Ts model