scholarly journals Mechanics Parameter Optimization and Evaluation of Curtain Grouting Material in Deep, Water-Rich Karst Tunnels

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Hai Shi ◽  
Mingzhou Bai ◽  
Shaochuan Xing
Keyword(s):  
Great Influence ◽  
Economic Losses ◽  
Wave Form ◽  
Engineering Construction ◽  
Grouting Material ◽  
Curtain Grouting ◽  
Speed Up ◽  
The Stability ◽  
Control Water

Mud and water often gush suddenly during the construction process of deep buried karst tunnels, which may cause serious accidents and result in major economic losses. Accordingly, for tunnels buried in deep rich water districts, discovering how to effectively control water gushing and ensure the stability of surrounding rock has great influence on the safety of engineering construction. The case study in this paper simulates the water-rich section of Dou-mo tunnel from Shanghai to Kunming of China. Numerical analysis was used to simulate the construction of the curtain grouting section and to evaluate the effects of the various curtain grouting parameters. The optimal grouting parameters were selected and then evaluated by applying them to the grouting method. The results show that (1) the grouting effect is the most notable one when the thickness of the grouting circle is outside the 4 m range of the tunnel contour. (2) In the same circle, the grouting quantity of the same ring is presented as a wave form. Therefore the number of the same ring grouting holes should reduce and increase the distance between the adjacent grouting holes appropriately to reduce the number of grouting holes and speed up the grouting progress.

Experimental Investigation on Dynamic Constitutive Model of Saturated Sandy Pebble Soil

2010 ◽  
Vol 160-162 ◽  
pp. 599-602
Author(s):  
Wen Guo ◽  
Ke Qi Liu ◽  
Hua Chuan Yao
Keyword(s):  
Experimental Investigation ◽  
Constitutive Model ◽  
Great Influence ◽  
Safety Evaluation ◽  
Response Analysis ◽  
Test Results ◽  
Seismic Response Analysis ◽  
Engineering Construction ◽  
The Stability ◽  
Earthquake Safety

The dynamic constitutive model could show the dynamic characteristics of soil, so it was essential in ground motion in earthquake safety evaluation and seismic response analysis of soil, and it had great influence on research and analysis of seismic performance of soil and the stability of the foundation. Sandy pebble soil distributed abroad in Sichuan, so it was widely used in engineering construction. Based on the test results of dynamic triaxial non-drain consolidation test，this paper studied the dynamic constitutive model of saturated sandy pebble soil to provide reference for the future use.

scholarly journals BIM AND GIS: WHEN PARAMETRIC MODELING MEETS GEOSPATIAL DATA

2017 ◽  
Vol IV-5/W1 ◽  
pp. 1-8 ◽  
Author(s):  
L. Barazzetti ◽  
F. Banfi
Keyword(s):  
Research Work ◽  
Parametric Modeling ◽  
Geospatial Data ◽  
Parametric Modelling ◽  
Engineering Construction ◽  
Combined Use ◽  
Speed Up ◽  
The Moment ◽  
Gis Software

Geospatial data have a crucial role in several projects related to infrastructures and land management. GIS software are able to perform advanced geospatial analyses, but they lack several instruments and tools for parametric modelling typically available in BIM. At the same time, BIM software designed for buildings have limited tools to handle geospatial data. As things stand at the moment, BIM and GIS could appear as complementary solutions, notwithstanding research work is currently under development to ensure a better level of interoperability, especially at the scale of the building. On the other hand, the transition from the local (building) scale to the infrastructure (where geospatial data cannot be neglected) has already demonstrated that parametric modelling integrated with geoinformation is a powerful tool to simplify and speed up some phases of the design workflow. This paper reviews such mixed approaches with both simulated and real examples, demonstrating that integration is already a reality at specific scales, which are not dominated by “pure” GIS or BIM. The paper will also demonstrate that some traditional operations carried out with GIS software are also available in parametric modelling software for BIM, such as transformation between reference systems, DEM generation, feature extraction, and geospatial queries. A real case study is illustrated and discussed to show the advantage of a combined use of both technologies. BIM and GIS integration can generate greater usage of geospatial data in the AECOO (Architecture, Engineering, Construction, Owner and Operator) industry, as well as new solutions for parametric modelling with additional geoinformation.

Visual-Neural Correlate of Speechreading Ability in Normal-Hearing Adults

1982 ◽  
Vol 25 (4) ◽  
pp. 521-527 ◽  
Author(s):  
David C. Shepherd
Keyword(s):  
Normal Hearing ◽  
Wave Form ◽  
Firing Time ◽  
Neural Firing ◽  
Neural Correlate ◽  
Retest Reliability ◽  
Repeated Word ◽  
Negative Peak ◽  
The Stability ◽  
Test Retest Reliability

In 1977, Shepherd and colleagues reported significant correlations (–.90, –.91) between speechreading scores and the latency of a selected negative peak (VN 130 measure) on the averaged visual electroencephalic wave form. The primary purpose of this current study was to examine the stability, or repeatability, of this relation between these cognitive and neurophysiologic measures over a period of several months and thus support its test-retest reliability. Repeated speechreading word and sentence scores were gathered during three test-retest sessions from each of 20 normal-hearing adults. An average of 56 days occurred from the end of one to the beginning of another speechreading sessions. During each of four other test-retest sessions, averaged visual electroencephalic responses (AVER s ) were evoked from each subject. An average of 49 clays intervened between AVER sessions. Product-moment correlations computed among repeated word scores and VN l30 measures ranged from –.61 to –.89. Based on these findings, it was concluded that the VN l30 measure of visual neural firing time is a reliable correlate of speech-reading in normal-hearing adults.

SEISMIC RISK AND RESILIENCE ASSESSMENT OF INDUSTRIAL FACILITIES: CASE STUDY ON A BLACK CARBON PLANT

2020 ◽  
Author(s):  
George Karagiannakis
Keyword(s):  
Seismic Risk ◽  
Numerical Models ◽  
Fragility Curves ◽  
Human Life ◽  
Mitigation Strategies ◽  
Economic Losses ◽  
Risk And Resilience ◽  
Industrial Plants ◽  
Plant Equipment

This paper deals with state of the art risk and resilience calculations for industrial plants. Resilience is a top priority issue on the agenda of societies due to climate change and the all-time demand for human life safety and financial robustness. Industrial plants are highly complex systems containing a considerable number of equipment such as steel storage tanks, pipe rack-piping systems, and other installations. Loss Of Containment (LOC) scenarios triggered by past earthquakes due to failure on critical components were followed by severe repercussions on the community, long recovery times and great economic losses. Hence, facility planners and emergency managers should be aware of possible seismic damages and should have already established recovery plans to maximize the resilience and minimize the losses. Seismic risk assessment is the first step of resilience calculations, as it establishes possible damage scenarios. In order to have an accurate risk analysis, the plant equipment vulnerability must be assessed; this is made feasible either from fragility databases in the literature that refer to customized equipment or through numerical calculations. Two different approaches to fragility assessment will be discussed in this paper: (i) code-based Fragility Curves (FCs); and (ii) fragility curves based on numerical models. A carbon black process plant is used as a case study in order to display the influence of various fragility curve realizations taking their effects on risk and resilience calculations into account. Additionally, a new way of representing the total resilience of industrial installations is proposed. More precisely, all possible scenarios will be endowed with their weighted recovery curves (according to their probability of occurrence) and summed together. The result is a concise graph that can help stakeholders to identify critical plant equipment and make decisions on seismic mitigation strategies for plant safety and efficiency. Finally, possible mitigation strategies, like structural health monitoring and metamaterial-based seismic shields are addressed, in order to show how future developments may enhance plant resilience. The work presented hereafter represents a highly condensed application of the research done during the XP-RESILIENCE project, while more detailed information is available on the project website https://r.unitn.it/en/dicam/xp-resilience.

Applications of random graphs

2017 ◽  
Author(s):  
A.C.C. Coolen ◽  
A. Annibale ◽  
E.S. Roberts
Keyword(s):  
Social Networks ◽  
Random Graphs ◽  
Interaction Network ◽  
Power Grids ◽  
Protein Protein Interaction ◽  
Topological Features ◽  
First Case ◽  
The Stability ◽  
Protein Protein Interaction Network

This chapter reviews graph generation techniques in the context of applications. The first case study is power grids, where proposed strategies to prevent blackouts have been tested on tailored random graphs. The second case study is in social networks. Applications of random graphs to social networks are extremely wide ranging – the particular aspect looked at here is modelling the spread of disease on a social network – and how a particular construction based on projecting from a bipartite graph successfully captures some of the clustering observed in real social networks. The third case study is on null models of food webs, discussing the specific constraints relevant to this application, and the topological features which may contribute to the stability of an ecosystem. The final case study is taken from molecular biology, discussing the importance of unbiased graph sampling when considering if motifs are over-represented in a protein–protein interaction network.

Supplier Development at LG Electronics

2020 ◽  
Author(s):  
Hyojin Kim ◽  
Daesik Hur ◽  
Tobias Schoenherr
Keyword(s):  
Management Practice ◽  
Digital Technologies ◽  
Supply Management ◽  
Future Research ◽  
Supplier Development ◽  
Environmentally Conscious ◽  
Competitive Capabilities ◽  
The Stability ◽  
Buyer Firm

Supplier development has been a critical supply management practice since the 1990s. In many instances, it has even become imperative for buyer firms to support and prepare their supply bases for uncertain economic and market environments, socially and environmentally conscious customers, advances in digital technologies, and increasing competition. Yet, research that approaches supplier development with the objective to advance all these dimensions in an integrated fashion is scarce. This study fills this void by exploring how a buyer firm may address these emerging challenges in its supply base. Specifically, an in-depth case study of LG Electronics explores how the firm designs and operates multidimensional supplier development activities to foster the stability and sustainability of its supply base while enhancing its core suppliers’ competitive capabilities. This chapter illustrates how supplier development can be taken to the next level, presents implications for managerial practice, and outlines promising future research avenues.

scholarly journals The application of environmental governance for sustainable watershed-based management

2021 ◽  
Author(s):  
Seiichi Kagaya ◽  
Tetsuya Wada
Keyword(s):  
Environmental Protection ◽  
River Basin ◽  
Watershed Management ◽  
Water Use ◽  
Flood Control ◽  
Environmental Governance ◽  
Planning Process ◽  
Environment Assessment ◽  
Control Water

AbstractIn recent years, it has become popular for some of countries and regions to adapt the system of governance to varied and complex issues concerned with regional development and the environment. Watershed management is possibly the best example of this. It involves flood control, water use management and river environment simultaneously. Therefore, comprehensive watershed-based management should be aimed at balancing those aims. The objectives of this study are to introduce the notion of environmental governance into the planning process, to establish a method for assessing the alternatives and to develop a procedure for determining the most appropriate plan for environmental governance. The planning process here is based on strategic environment assessment (SEA). To verify the hypothetical approach, the middle river basin in the Tokachi River, Japan was selected as a case study. In practice, after workshop discussions, it was found to have the appropriate degree of consensus based on the balance of flood control and environmental protection in the watershed.

Capturing Transformative Moments in a Participatory Values-Based Event

2021 ◽  
pp. 154134462199624
Author(s):  
Felix Okechukwu Dike ◽  
JohnBosco Chika Chukwuorji
Keyword(s):  
Transformative Learning ◽  
Learning Outcomes ◽  
Study Design ◽  
Present Moment ◽  
Case Study Design ◽  
Fresh Perspective ◽  
The Stability

The theory of transformative learning (TL) has been criticized secondhand for its lack of clarity in capturing and explaining in detail the processes undergone by learners who are going through TL experiences and their link to learning outcomes. Using a case study design, and carefully synthesized TL processes (TLPs) from Mezirow’s TL theory, we present—moment by moment—the TLPs linked to outcomes identified among a group of teachers who participated in a values-based workshop. Participants were followed through interviews for over 72 weeks to trace the stability of their TL outcome. TL processes identified were compared to Mezirow’s 10 processes. The article discusses ontological transformations gained and offers fresh perspective to identifying TLPs that can be linked to outcomes.

scholarly journals The effect of flexural–torsional buckling on the stability of timber members: a case study

2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Osama A. B. Hassan
Keyword(s):  
Axial Compression ◽  
Bending Moment ◽  
List Type ◽  
Torsional Buckling ◽  
Solution Methods ◽  
Simplified Solution ◽  
The Stability ◽  
Flexural Torsional Buckling ◽  
Building Engineering

Abstract This study investigates the stability of timber members subjected to simultaneously acting axial compression and bending moment, with possible risk for torsional and flexural–torsional buckling. This situation can occur in laterally supported members where one side of the member is braced but the other side is unbraced. In this case, the free side will buckle out of plane while the braced side will be prevented from torsional and flexural–torsional buckling. This problem can be evident for long members in timber-frame structures, which are subjected to high axial compression combined with bending moments in which the member is not sufficiently braced at both sides. This study is based on the design requirement stated in Eurocode 5. Solution methods discussed in this paper can be of interest within the framework of structural and building Engineering practices and education in which the stability of structural elements is investigated. Article Highlights This case study investigates some design situations where the timber member is not sufficiently braced. In this case, a stability problem associated with combined torsional buckling and flexural buckling can arise. The study shows that the torsional and/or flexural–torsional buckling of timber members can be important to control in order to fulfil the criteria of the stability of the member according to Eurocode 5 and help the structural engineer to achieve safer designs. The study investigates also a simplified solution to check the effect of flexural torsional buckling of laterally braced timber members.

scholarly journals Determinants of judges’ career choices and productivity: a Polish case study

2021 ◽  
Author(s):  
Przemysław Banasik ◽  
Katarzyna Metelska-Szaniawska ◽  
Małgorzata Godlewska ◽  
Sylwia Morawska
Keyword(s):  
Career Choices ◽  
Social Recognition ◽  
District Courts ◽  
Self Monitoring ◽  
Administrative Supervision ◽  
Judicial Efficiency ◽  
The Status ◽  
Service Mission ◽  
The Stability

AbstractThe goal of this paper is to identify factors which affect judges’ productivity and career choice motives with the view of increasing judicial efficiency. Specifically, the investigation focuses on such aspects as judges’ remuneration, promotion, threat of judgment revocation, service/mission, periodic assessment, the threat of a complaint about protracted proceedings or of disciplinary proceedings, the threat of destabilization of the employment relationship, status/prestige of the profession, power/authority, social recognition, leisure, as well as administrative supervision and self-monitoring. To this end, a survey was conducted among judges of three of the largest Polish regional courts and subordinate district courts. The descriptive and statistical analyses show that judges’ care for the number of cases resolved, proxying for their productivity, is significantly correlated with self-monitoring of their adjudication activity. The stability of employment, the status/prestige of the profession and a relatively high remuneration are the most important factors in terms of judges’ career choices. In their care for the number of cases resolved remuneration is, albeit, no longer a relevant factor. Judges monitor their productivity due to reasons other than remuneration, possibly the sense of service/mission and the threat of various adverse consequences, the evidence for which is, however, also rather weak.

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