Fragile Locations Research Articles

Seismic behavior of piles-supported pier-superstructure to liquefaction-induced lateral spreading considering variability of soil permeability

This study characterizes the effect on different engineering demand parameters owing to lateral spreading caused by liquefaction. 1 g large-scale shaking table experiments were conducted along with efficient numerical simulations of the piles-supported pier-superstructure system response to strong earthquakes. An integrated nonlinear numerical method was established and evaluated with the results of the shake table experiments, and the seismic response characteristics of the system was discussed by combining the experimental and numerical results. The influence of the initial soil hydraulic conductivity on soil liquefaction was evaluated and the inertia and kinematic effects were evaluated employing cross-correlation analyses. The results indicated that soil softening diminished as the permeability coefficient increased, and consequently the lateral displacements of soil and superstructure decreased, and the superstructure acceleration demand increased. Increased permeability coefficient shifted the fragile location of the piles-supported pier-superstructure from the liquefiable soil bottom to the pier bottom. Finally, the inertial effect increased on pile curvature near pile head while the kinematic effect decreased as the permeability coefficient increased.

Tourism and the Environmental Components Coexisting in the Himalayas: A Trade-Off Between the Two

ABSTRACT Resource intensiveness diminishes ecological services and future eco-benefits, increasing poverty and inequality. The pursuit threshold is planning and managing resources, which can jeopardize or help fragile locations, depending on the management strategy. This study attempted to evaluate the trade-off between tourism and the environment using a conceptual modeling approach involving stakeholders. The Environmental Impact Assessment (EIA), a technique with the Leopold Matrix, was used for evaluating the magnitude and importance between tourism activities and environmental components. We identified 14 major tourist activities that can affect six different environmental components with other potential consequences and how the environmental components are important to tourism activities. In consultation with the stakeholders, the Delphi Survey with Content Validation Ratio (CVR) was used to determine the list of tourism activities, environmental factors, and potential consequences. The severity, magnitude, and importance were estimated based on the perceived information from experts. In conclusion, the Environmental Impact Assessment (EIA) is an invaluable tool for evaluating, monitoring and mitigating the adverse effects of tourism. Its use holds significant potential in the pursuit of sustainable tourism management.

In-situ EBSD investigation of plastic damage in a 316 austenitic stainless steel and its molecular dynamics (MD) simulations

The damage evolution process in 316 austenitic stainless steel at the plastic stage were investigated in this paper by using the in-situ EBSD technique and MD simulation in combination. The damage mechanisms of 316 steel are typified by an intergranular and intragranular mixed mode. The in-situ EBSD results showed that the intergranular damage was the defects formation at the GBs, and the twin-GB intersections and the triple GB are the preferred damage sites. While the intragranular damage was manifested by the mixing of lattice orientation change, intragranular flaws appearance, and twin degradation; The MD simulation results manifested that the initial lattice structure changed after the plastic strain, and the continues increase of the atom displacement resulted in the defect formation. The simulation results also verified that the twin-GB intersection site could be a fragile location, the void preferentially appeared here, and the disorder degree of atoms over here were great. In addition, the defects also generated at the triple GB, which indicated that the triple GB could also be a weak location.

Exploring prosocial and environmental motivations of frontier tourists: implications for sustainable space tourism

While there are plans for spacecraft to take private travellers to the edge of space, we are yet to see this occur beyond a few individuals. Before this happens in larger numbers, research is needed about the sustainability of private space flight, including potential travellers’ awareness of and views about the environmental implications of their spaceflight. This article aims to address this gap by examining the travel motivations of frontier tourists – those individuals who seek to visit some of the most fragile locations on and off the planet, including outer space – connected to the environmental sustainability of this travel. Given space tourism is a subset of frontier tourism, studying the latter might help us to understand the behaviour of the nascent space tourist. Qualitative interviews with frontier tourists were conducted and analysed using grounded theory techniques. While participants referred to the unspoilt characteristics of places, untainted by human activity, as an integral part of their travel experience, many did not see the paradox inherent in this travel. Some who did referred to prosocial motivations connected to environmental causes and saw themselves as ambassadors for conservation. The article concludes with the implications of these findings for sustainable space tourism.

Evaluation Method for Cohesive Crack Propagation in Fragile Locations of RCC Dam Using XFEM

Roller compacted concrete (RCC) dams own a large number of horizontal construction layers, which can easily lead to weak joints among layers and generate interlayer joints with different scales to reduce the dam bearing capacity. In this study, extended finite element method (XFEM) is used to simulate crack propagation, the finite element description is first taken on the strong discontinuity. Subsequently, the displacement function of the crack-tip in the quadrilateral element and the geometric determination method of the crack-tip strengthening region are established. Afterwards, the discrete form of the governing equation is derived and the XFEM increment discretization method of the cohesive crack with the crack-tip reinforcement is proposed using the virtual node method to represent the discontinuity of the fracture element. These methods are validated through simulating mixed-mode cracking of one-sided notched asymmetric four-point bending beam. Eventually, the proposed methods are applied to RCC gravity dam to study the development rule and propagation path of the interlayer joints, so as to evaluate the effect of different lengths of the interlayer joints on the dam structural performance. The estimated critical values of dam deformation are helpful to prevent the dam failure during long term operation.

Seismic analysis and retrofitting countermeasure for 1315 kV capacitor with multi-column posts

A number of power substations and converter stations are inevitably built in high earthquake intensity regions. There are many types of electrical equipment with multi-column posts in power substations and converter stations. The PLC/RI capacitor with high seismic vulnerability is a typical electrical equipment with multi-column posts. A 1315 kV PLC/RI capacitor was modeled and analyzed using finite element technique. The modal analysis results show that the primary frequency of the capacitor is close to the earthquake dominant frequency. Additionally, the 2nd, 3rd and 4th order frequencies are within the range of the flat segment of the seismic response spectrum. After performing seismic analysis, the most fragile location was identified, that is the porcelain insulator at the bottom of the capacitor. The stress safety factor of the porcelain insulator is 0.71, which indicates the capacitor does not meet the seismic requirement for peak ground acceleration (PGA) = 0.3 g. To improve the seismic performance of capacitor with multi-column posts, enhancing connection stiffness of the structure is proposed. Based on this countermeasure, the thickness of the connecting plate between the upper hollow composite insulators and the porcelain insulators at the bottom of capacitor was increased from 20 mm to 50 mm. After the optimization, the 1315kV PLC/RI capacitor satisfies the seismic requirement for PGA value of 0.3 g.

What Is Still Necessary for Supporting the SDG7 in the Most Vulnerable Contexts?

The common agreement of the United Nation members pushes the 2030 Agenda ahead to alleviate poverty and ensure wellbeing for all, recognizing energy as a crucial pathway to achieving this goal under three core dimensions: human development, sustainable economic growth, and environmental sustainability. Affordable and clean energy is represented by the Sustainable Development Goal 7 (SDG7). This great scope represents a multifaceted challenge for all countries, especially for the most disadvantaged environments such as small islands and rural areas from developing countries. Both small islands and rural areas experience a scarcity of goods and services such as energy and are isolated from markets, have lack of human resources, difficulties in deploying economies of scale, and other issues that affect their development. Along the same line, their energy security is limited by their dependence on imported fuels, increasing electricity prices or making it infeasible to access electricity. This research builds the state of the art of off-grid energy systems for both contexts based on an extensive review of literature. The evidence shows that moving sustainable energy systems forward requires getting more people involved, the application of several business models, prevalent technological innovations, and the application of technical quality procedures. This perspective would really help to address the vulnerabilities of fragile locations. Here, auctions, the Energy Service Company, community, and Pay-As-You-Go (PAYG) models and renewable energy projects based on mature technology present a great opportunity for a sustainable future, powering a nexus among energy, environment, and society.

Borderline innovation, marginalized communities: universities and inclusive development in ecologically fragile locations

ABSTRACTWhere do the notional boundaries of the concept of innovation lie, and what does this mean for the study of innovation in socially marginalized settings, where changes are localized, incremental, informal, and social? How can this help us understand new aspects of innovation and inclusive development? To explore these questions, we draw on an evidence base describing university interactions with highly marginalized communities in South Africa, Uganda, and Botswana. These universities have established interface structures through which participative knowledge-building has led to new processes and social structures that have helped communities to address their livelihoods challenges. At the same time, universities have benefitted from the interaction, gaining from the communities’ local knowledge. This paper explores the characteristics of these interactions in order to open up a new empirical frontier, and also to reflect on the utility of innovation systems theory for understanding borderline cases of innovation that take place in informal settings and marginalized communities.

Urban Settlement Spatial Analysis in Permanent Preservation Area of M’boicy Watershed River, Foz do Iguaçu City in Brazil

Irregular urban settlement increases environmental impacts, especially when these occupations occur in fragile location, as the environmental preservation areas. In these areas, also defined as Permanent Preservation Area (PPA), the presence of watersheds is common, which is the factor that increases the need of protecting them from anthropic actions. Those actions deteriorate the environment and mainly the watercourses. This research objective is to identify and estimate the environmental risks of M’Boyci watershed River PPA occupied areas by urban population. The risk analysis approach, at this PPA in Foz do Iguacu City in Brazil, is able to support public interventions in order to reestablish the PPA natural conditions. To reach this goal, it was necessary to use cartographical representation images, generated from digital orthophotos analyzed through free geographical information systems. The overlap and the contrast of geographical data related to preservation in urban areas show that urban occupation reaches almost 40% of the permanent preservation area. Complementarily, it is evidenced that the development of a risk map identifies PPA areas characterized by a greater concentration of irregular settlement, contributing to the planning process of residents, relocation actions and recovery of degraded areas.

Cold Hard Cache: The Arctic Drilling Controversy

On 27 May 2010, with crude oil gushing into the Gulf of Mexico after the explosion of BP’s Deepwater Horizon oil rig, the Obama administration announced it would pause offshore drilling plans in the Arctic Ocean, one of the planet’s most pristine ecosystems.1 Hailed by environmental groups, the decision was a major setback to the oil industry, which was gearing up to tap what’s expected to be vast amounts of oil and gas lying under the Arctic’s treacherous waters, wher e sustained winds blow at 30 to 50 miles per hour, and menacing chunks of floating “pack ice,” some hundreds of feet wide and dozens of feet thick, threaten marine traffic. With shallow-water, near-shore reserves increasingly tapped out in the Gulf of Mexico, oil companies are being forced into more challenging terrain to sustain domestic energy production. That means pushing into much deeper geology in the Gulf of Mexico—much of it more than a mile underwater—and also into ecologically fragile locations off the coast of Alaska. In decades past, oil companies didn’t prioritize the offshore Arctic for development because drilling there was too expensive. Oil prices simply weren’t high enough to sustain production windows limited to just a few months in summer, when thawing seas make drilling possible, explains Layla Hughes, an attorney and senior program officer for Arctic oil, gas, and shipping policy at the WWF in Juneau. But as economies in China, India, and Brazil have grown, global fuel demands have risen accordingly,2 driving prices higher and making offshore Arctic development economically viable. “Prices started going up in the late nineties, and they’re projected to stay high,” Hughes says. Oil companies now have to prove they can extract those resources safely, without compromising an ecosystem that might never recover from the effects of a large blowout. Dana Wetzel, an ecotoxicologist at Mote Marine Laboratory with 10 years’ research experience in the Arctic, says oil degradation depends largely on temperature. When exposed to frigid water, oil turns quickly into a thick, tarry substance that microbes can’t easily degrade. The 1989 Exxon Valdez spill, which occurred roughly 400 miles south of the Arctic Circle, likely underestimates the full environmental impact of a blowout even farther to the north. “The Valdez was a horrible spill in a rich marine ecosystem, but you didn’t have the oiling of the sea ice,” Wetzel says. “If you taint sea ice with oil, you’re never going to get rid of it. And those ice floes are home to walruses, seals, and polar bears. Many people survive up there by subsistence hunting, and to contaminate their food is one of the worst moral blows you can deliver to those communities.”3

液晶ディスプレイの故障解析へのＦＩＢ／ＴＥＭの応用

The fragile locations of process-induced defects in hydrogenated amorphous silicon thin-film transistors (a-Si : H TFTs), which are used as elements of active-matrix liquid crystal displays, are investigated by combining focused ion beam (FIB) techniques with cross-sectional transmission electron microscopy (X-TEM). This article also describes how an array can be characterized by using a TFT array tester and a scanning force microscope that can detect, accurately locate, and identify pixel faults. The rapid FIB technique is applied to TFT failure analysis problems which require very localized etching without inducing mechanical stress. We demonstrate how these techniques are used to characterize TFT defects such as portions of the TFT multilayer damaged by micro-scratch and foreign materials. These layers cause short-circuit failures. These observations lead to identification of the fault and analysis of its cause, which in turn lead to a marked yield improvement.

Transmission electron microscopy of thin-film transistors on glass substrates

The recent attention paid to sample preparation of multilayered structure on glass substrates indicates that cross-sectional transmission electron microscopy (X-TEM) are of considerable interest for their potential effectiveness in thin-film transistor liquid crystal display (TFT-LCD) application. We describe the significant features of our failure analysis problem which involves some difficulties: fragile location, anomalous, and rare defect. An application of focused ion beam (FIB) etching to specimen preparation for X-TEM observation is introduced. We demonstrated that the FIB technique, which allows very localized etching without inducing mechanical stress to thin TEM sample, is very convenient for this delicate location. We also demonstrate that our FIB etching technique is capable of high thinning rates, which allows rapid production of high-quality TEM specimen. Finally, we demonstrate how faulty TFTs including long and fragile protrusions such as whiskers, can be characterized by means of FIB and X-TEM combination.

Cross-Sectional Tem Sample Preparation Method Using Fib Etching for Thin-Film Transistor

AbstractA rapid and precise sample preparation method using focused ion beam (FIB) etching was developed for cross-sectional transmission electron microscopy (X-TEM) analysis of a thin-film transistor (TFT) fabricated on a glass substrate. Gallium (Ga) ions accelerated at 30 kV and at various incident beam angles were applied during FIB etching to create a uniform thin wall. We successfully prepared X-TEM specimens of long and fragile aluminum (Al) whiskers formed on thin Al films in TFT metallization, where a strong charge is built up during FIB etching. The effect of ion-beam-assisted tungsten deposition prior to FIB etching is discussed. A whisker having a length not exceeding approximately 10 #x00B5;m can be successfully etched to a thickness of 200 nm while keeping its original shape. The performance of this technique is demonstrated in applications to etching at other fragile locations related to TFTs.