scholarly journals Intelligent Risk Assessment for Dewatering of Metro-Tunnel Deep Excavations

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
X. W. Ye ◽  
L. Ran ◽  
T. H. Yi ◽  
X. B. Dong

In recent years, China has been undergoing a metro railway construction boom in order to alleviate the urban traffic congestion problem resulting from the rapid urbanization and population growth in many metropolises. In the construction of metro systems, deep excavations and continuous dewatering for construction of the metro tunnels and stations remain a challenging and high risk task in densely populated urban areas. Intelligent computational methods and techniques have exhibited the exceptional talent in dealing with the complicated problems inherent in the deep excavation and dewatering practice. In this paper, an intelligent risk assessment system for deep excavation dewatering is developed and has been applied in the project of Hangzhou Metro Line 1 which is the first metro line of the urban rapid rail transit system in Hangzhou, China. The specific characteristics and great challenges in deep excavation dewatering of the metro-tunnel airshaft of Hangzhou Metro Line 1 are addressed. A novel design method based on the coupled three-dimensional flow theory for dewatering of the deep excavation is introduced. The modularly designed system for excavation dewatering risk assessment is described, and the field observations in dewatering risk assessment of the airshaft excavation of Hangzhou Metro Line 1 are also presented.

2015 ◽  
Vol 40 (4) ◽  
pp. 50-54
Author(s):  
Yin Pan ◽  
Tiejun Zhou

Due to the rapid urbanization in China, the living environment in urban areas improves considerably, while that in rural settlements does not improve remarkably, or even worsens. The purpose of the research is to propose an organizational approach to the improvement of the living environment in the poverty-stricken rural settlements and an architectural design pattern under a variety of requirements in the context of China’s rapid urbanization and socio-economic development in the redevelopment of rural settlements in Yongsheng Village, Lizhuang Town, Yibin City of Sichuan Province in Southwest China. In this redevelopment project, the architects, as the important third party, are not just architects in the traditional sense in that they are involved in the organizational process and architectural design throughout the whole project. The redevelopment project has been completed, and is aimed at providing a scientific redevelopment model and a design method for other rural residents by guiding them in the improvement of their living environment under a variety of restrictions.


2015 ◽  
Vol 12 (8) ◽  
pp. 8005-8033 ◽  
Author(s):  
X. Jiang ◽  
H. Tatano

Abstract. Information about the spatial distribution of flood risk is important for integrated urban flood risk management. Focusing on urban areas, spatial flood risk assessment must reflect all risk information derived from multiple flood sources: rivers, drainage, coastal flooding etc. that may affect the area. However, conventional flood risk assessment deals with each flood source independently, which leads to an underestimation of flood risk in the floodplain. Even in floodplains that have no risk from coastal flooding, flooding from river channels and inundation caused by insufficient drainage capacity should be considered simultaneously. For integrated flood risk management, it is necessary to establish a methodology to estimate flood risk distribution across a floodplain. In this paper, a rainfall design method for spatial flood risk assessment, which considers the joint effects of multiple flood sources, is proposed. The concept of critical rainfall duration determined by the concentration time of flooding is introduced to connect response characteristics of different flood sources with rainfall. A copula method is then adopted to capture the correlation of rainfall amount with different critical rainfall durations. Rainfall events are designed taking advantage of the copula structure of correlation and marginal distribution of rainfall amounts within different critical rainfall durations. A case study in the Otsu River Basin, Osaka prefecture, Japan was conducted to demonstrate this methodology.


Author(s):  
Chenxi Li ◽  
Zenglei Xi

Scholars have paid much attention to the problems existing in the land expropriation risk assessment system and the sound countermeasures from a qualitative perspective. Empirical research on land expropriation social stability risk assessment from the micro-level perspective is limited. This study analyzed the Chinese social stability risk assessment system of land expropriation though a case study of a land expropriation project in China. The current social stability risk assessment system of land expropriation, which includes the assessment purposes, principles, contents, methods, and results, was analyzed. We concluded with lessons and deficiencies from the current social stability risk assessment system. The research findings show that: (1) the current land expropriation risk assessment system mostly takes the land administration department as the main body of responsibility, identifies the risks by means of seminars, visits, letters, and visits, and takes the opinion of the masses or experts as the risk assessment result. (2) The current land expropriation risk assessment system should be standardized in terms of defining the risk assessment of land expropriation, improving the land expropriation risk assessment system and optimizing land expropriation assessment procedures. This paper provides a reference for the sustainable development of land use in rural and urban areas in China.


Agronomie ◽  
2003 ◽  
Vol 23 (1) ◽  
pp. 75-84 ◽  
Author(s):  
Andy Hart ◽  
Colin D. Brown ◽  
Kathy A. Lewis ◽  
John Tzilivakis

2007 ◽  
Vol 7 ◽  
pp. 113 ◽  
Author(s):  
Raj Man Shrestha

The increase of population in Kathmandu valley is bringing a considerable change in cropping system. Rapid urbanization and introduction of new agriculture technology have encouraged the valley’s farmers to change their cropping patterns from traditional (low value crops) to new crops (high value crops). According to numerous studies made in Nepal, the change is seen considerably in winter crops than in summer crops and the land under cultivation of green leafy vegetables is increasing rapidly in the urban and semi-urban areas. An average growth of population at 3 % in the valley during the period 1951-2001 has resulted in the rapid expansion of area under urban coverage (24.6 % growth per year from 1984 - 2000) has made agriculture land of Katmandu valley to decline per year by 2.04 % (836.27 ha per year). If this trend of decline in agriculture land in Kathmandu valley continues in future too, it is expected that there will be no agriculture land left over by two and half decades in the valley. The planners should take note of this fact that if fertile land of Katmandu valley is to be preserved for agriculture necessary planning is urgently needed. <i>Nepal Journal of Science and Technology</i> Vol. 7, 2006


2019 ◽  
Vol 1 (2) ◽  
pp. 144-156
Author(s):  
Indri Handayani ◽  
Erick Febriyanto ◽  
Andrew Jethro

The lecture support system in Higher Education has information about student identity in each system, such as profile photos, names, NIM (Student Registration Number) and according to system requirements. An assessment on the public viewboard is an Online Assessment System aimed at improving services at Raharja University. However, in the multiplication flow system still has 3 disadvantages, namely, students do not yet have the facility to see the allocation value between friends in one class in one course to be able to improve the results of lecture grades with classmates and also between classes. In class design Popular writers also do five methods, namely the method of analysis, method of literature review, observation method, design method, and then implemented. With the existence of this study, there are 3 Benefits, namely, students can see the value determined by classmates, can improve the value, and lecturers can ensure the value given must be recognized by students.    


Author(s):  
Bogdan Korniyenko ◽  
Lilia Galata

In this article, the research of information system protection by ana­ ly­ zing the risks for identifying threats for information security is considered. Information risk analysis is periodically conducted to identify information security threats and test the information security system. Currently, various information risk analysis techni­ ques exist and are being used, the main difference being the quantitative or qualitative risk assessment scales. On the basis of the existing methods of testing and evaluation of the vulnerabilities for the automated system, their advantages and disadvantages, for the possibility of further comparison of the spent resources and the security of the information system, the conclusion was made regarding the deter­ mi­ nation of the optimal method of testing the information security system in the context of the simulated polygon for the protection of critical information resources. A simula­ tion ground for the protection of critical information resources based on GNS3 application software has been developed and implemented. Among the considered methods of testing and risk analysis of the automated system, the optimal iRisk methodology was identified for testing the information security system on the basis of the simulated. The quantitative method Risk for security estimation is considered. Generalized iRisk risk assessment is calculated taking into account the following parameters: Vulnerabili­ ty  — vulnerability assessment, Threat — threat assessment, Control — assessment of security measures. The methodology includes a common CVSS vul­ nerability assessment system, which allows you to use constantly relevant coefficients for the calculation of vulnerabilities, as well as have a list of all major vulnerabilities that are associated with all modern software products that can be used in the automated system. The known software and hardware vulnerabilities of the ground are considered and the resistance of the built network to specific threats by the iRisk method is calculated.


Aerospace ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 54
Author(s):  
Julia A. Cole ◽  
Lauren Rajauski ◽  
Andrew Loughran ◽  
Alexander Karpowicz ◽  
Stefanie Salinger

There is currently interest in the design of small electric vertical take-off and landing aircraft to alleviate ground traffic and congestion in major urban areas. To support progress in this area, a conceptual design method for single-main-rotor and lift-augmented compound electric helicopters has been developed. The design method was used to investigate the feasible design space for electric helicopters based on varying mission profiles and technology assumptions. Within the feasible design space, it was found that a crossover boundary exists as a function of cruise distance and hover time where the most efficient configuration changes from a single-main-rotor helicopter to a lift-augmented compound helicopter. In general, for longer cruise distances and shorter hover times, the lift-augmented compound helicopter is the more efficient configuration. An additional study was conducted to investigate the potential benefits of decoupling the main rotor from the tail rotor. This study showed that decoupling the main rotor and tail rotor has the potential to reduce the total mission energy required in all cases, allowing for increases in mission distances and hover times on the order of 5% for a given battery size.


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