Large scale filed experiment on the landslide dam breaching

2021 ◽  
Author(s):  
Wei Huang ◽  
Wengang Duan
Keyword(s):  
Large Scale ◽  
Landslide Dam ◽  
Frequency Of Occurrence ◽  
Mountain River ◽  
Dam Breach ◽  
Dam Breaks ◽  
Extreme Flood ◽  
Dam Breaching ◽  
Diversion Channel ◽  
The One

<p>Landslide dam breaching is the one of focus topics in the geophysical flows. The frequency of occurrence of landslide dam increases due to earthquake, climate change and mans activities in recent years. Once the dam breaks, it would trigger extreme flood downstream. A field experiment on landslide dam breach has been carried out on a small mountain river in Mianzhu, Sichuan Province, China from 23 November to 29 December, which aims to reveal impact of different diversion channel types on the dam breaching process as well as the resulting flood. The dam is of 4m high, 10~15m wide. the length of the dam crest is 5m, upstream downstream slopes of the dam are 1:2 and 1:5. Results show division channel can reduce the peak flood discharge obviously. The pilot vertical fall can trigger earlier back erosion and thus peak discharge appears earlier with smaller magnitude.</p>

scholarly journals Influences of Spillway Section Morphologies on Landslide Dam Breaching

2021 ◽  
Vol 9 ◽  
Author(s):  
Meng Yang ◽  
Qiming Zhong ◽  
Shengyao Mei ◽  
Yibo Shan
Keyword(s):  
Cross Section ◽  
Landslide Dam ◽  
Longitudinal Section ◽  
Disaster Mitigation ◽  
Slope Ratio ◽  
Dam Breach ◽  
Time To Peak ◽  
Dam Breaching ◽  
Bottom Width ◽  
The Cross

Spillway excavation is often adopted as a precautionary engineering measure for disaster mitigation before landslide dam breaching. Based on the landslide dam breach mechanisms, this paper focuses on developing a numerical model to comprehensively discuss the issue based on three documented landslide dam failures, such as Tangjiashan, Xiaogangjian, and Baige landslide dams. The spillway cross section morphologies were modeled with different sizes under common shape (i.e., an inverted trapezoid) and slope conditions. The influence of cross section on dam breach processes was analyzed under conditions of different depth, bottom width, slope ratio in the cross and longitudinal sections, with/without spillway. The following conclusions can be drawn: 1) excavation of a spillway can effectively reduce the peak breach flow, therefore delay the time to peak; 2) the peak breach flow dramatically decreases and the time to peak delays as the spillway depth increases; 3) the peak breach flow changes little and the time to peak occurs earlier with the increment in spillway bottom width; 4) the peak breach flow decreases and the time to peak delays with the decrease of slope ratio in cross section in the spillway; 5) the slope ratio in the longitudinal section has little influence on the breach process. Hence, if conditions permit, the spillway with large spillway depth, small bottom width, and gentle slope ratio in the cross section is the preferable section morphology for the emergency disposal of the landslide dam.

Large-scale field model tests of landslide dam breaching

2021 ◽  
pp. 106322
Author(s):  
Jie-yuan Zhang ◽  
Gang Fan ◽  
Hai-bo Li ◽  
Jia-wen Zhou ◽  
Xing-guo Yang
Keyword(s):  
Large Scale ◽  
Field Model ◽  
Landslide Dam ◽  
Model Tests ◽  
Dam Breaching ◽  
Scale Field ◽  
Large Scale Field

scholarly journals Effects of Grain Size Distribution on Landslide Dam Breaching—Insights From Recent Cases in China

2021 ◽  
Vol 9 ◽  
Author(s):  
Shengyao Mei ◽  
Shengshui Chen ◽  
Qiming Zhong ◽  
Yibo Shan
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Emergency Response ◽  
Landslide Dam ◽  
Dam Breach ◽  
Response Planning ◽  
Landslide Dams ◽  
Emergency Response Planning ◽  
Dam Breaching

Landslide dams are common geological features in mountainous areas, which may have serious consequences due to sudden breaching of the dam. An effective emergency response requires rapid and accurate forecasts regarding the landslide dam breach process. However, most existing models use physical, mechanical, and erosion properties of the mean or characteristic grain sizes to represent the landslide deposits. The grain size distribution and variations in soil erodibility with the depth in the landslide dam are not considered, resulting in an incorrect estimation of the breach flow hydrograph. In this paper, a simplified landslide dam classification is presented based on the formation mechanism and grain size distribution of landslide dams. Additionally, the influences of grain size distribution on the residual dam height and breach process of landslide dams are analyzed. This paper proposes a numerical method to rapidly obtain the breach hydrographs and breach morphology evolution of landslide dams. The new method can quickly classify landslide dams according to geological survey data and predict the landslide dam breach process. Three types of representative landslide dams in China are simulated to validate the proposed method. The breach flow discharge is significantly affected by spillway excavation. This contribution can provide rapid prediction of the landslide dam breach process and can be used for the emergency response planning before dam breaching.

First grammar books in the Habsburg Monarchy: individual initiative and regulatory interference by the state (1760s–1770s)

2020 ◽  
Vol 2019 (2 (11)) ◽  
pp. 137-157
Author(s):  
Olga V. Khavanova ◽  
Keyword(s):  
Eighteenth Century ◽  
State Policy ◽  
Large Scale ◽  
Language Use ◽  
Linguistic Diversity ◽  
Mother Tongue ◽  
German Language ◽  
Habsburg Monarchy ◽  
Private Initiative ◽  
The One

The second half of the eighteenth century in the lands under the sceptre of the House of Austria was a period of development of a language policy addressing the ethno-linguistic diversity of the monarchy’s subjects. On the one hand, the sphere of use of the German language was becoming wider, embracing more and more segments of administration, education, and culture. On the other hand, the authorities were perfectly aware of the fact that communication in the languages and vernaculars of the nationalities living in the Austrian Monarchy was one of the principal instruments of spreading decrees and announcements from the central and local authorities to the less-educated strata of the population. Consequently, a large-scale reform of primary education was launched, aimed at making the whole population literate, regardless of social status, nationality (mother tongue), or confession. In parallel with the centrally coordinated state policy of education and language-use, subjects-both language experts and amateur polyglots-joined the process of writing grammar books, which were intended to ease communication between the different nationalities of the Habsburg lands. This article considers some examples of such editions with primary attention given to the correlation between private initiative and governmental policies, mechanisms of verifying the textbooks to be published, their content, and their potential readers. This paper demonstrates that for grammar-book authors, it was very important to be integrated into the patronage networks at the court and in administrative bodies and stresses that the Vienna court controlled the process of selection and financing of grammar books to be published depending on their quality and ability to satisfy the aims and goals of state policy.

The Green New Deal

2019 ◽  
Author(s):  
Robert C. Hockett
Keyword(s):  
New Deal ◽  
Large Scale ◽  
Public Investment ◽  
Climate Science ◽  
Time Frame ◽  
White Paper ◽  
Good News ◽  
Carbon Neutrality ◽  
The One ◽  
In Virtue Of

This white paper lays out the guiding vision behind the Green New Deal Resolution proposed to the U.S. Congress by Representative Alexandria Ocasio-Cortez and Senator Bill Markey in February of 2019. It explains the senses in which the Green New Deal is 'green' on the one hand, and a new 'New Deal' on the other hand. It also 'makes the case' for a shamelessly ambitious, not a low-ball or slow-walked, Green New Deal agenda. At the core of the paper's argument lies the observation that only a true national mobilization on the scale of those associated with the original New Deal and the Second World War will be up to the task of comprehensively revitalizing the nation's economy, justly growing our middle class, and expeditiously achieving carbon-neutrality within the twelve-year time-frame that climate science tells us we have before reaching an environmental 'tipping point.' But this is actually good news, the paper argues. For, paradoxically, an ambitious Green New Deal also will be the most 'affordable' Green New Deal, in virtue of the enormous productivity, widespread prosperity, and attendant public revenue benefits that large-scale public investment will bring. In effect, the Green New Deal will amount to that very transformative stimulus which the nation has awaited since the crash of 2008 and its debt-deflationary sequel.

“Community Interests” and the Role of International Law in the Creation of a Global Market for Agricultural Land

2018 ◽  
Author(s):  
Jochen von Bernstorff
Keyword(s):  
International Law ◽  
Large Scale ◽  
Agricultural Land ◽  
Food Sovereignty ◽  
Global Market ◽  
Negative Consequences ◽  
Cultural Rights ◽  
Land Grab ◽  
Large Scale Land ◽  
The One

The chapter explores the notion of “community interests” with regard to the global “land-grab” phenomenon. Over the last decade, a dramatic increase of foreign investment in agricultural land could be observed. Bilateral investment treaties protect around 75 per cent of these large-scale land acquisitions, many of which came with associated social problems, such as displaced local populations and negative consequences for food security in Third World countries receiving these large-scale foreign investments. Hence, two potentially conflicting areas of international law are relevant in this context: Economic, social, and cultural rights and the principles of permanent sovereignty over natural resources and “food sovereignty” challenging large-scale investments on the one hand, and specific norms of international economic law stabilizing them on the other. The contribution discusses the usefulness of the concept of “community interests” in cases where the two colliding sets of norms are both considered to protect such interests.

scholarly journals Geomorphic effects of recurrent outburst superfloods in the Yigong River on the southeastern margin of Tibet

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kaiheng Hu ◽  
Chaohua Wu ◽  
Li Wei ◽  
Xiaopeng Zhang ◽  
Qiyuan Zhang ◽  
...  
Keyword(s):  
Landslide Dam ◽  
Upstream Migration ◽  
One Dimensional ◽  
Landform Evolution ◽  
Outburst Floods ◽  
Stepwise Method ◽  
Large Landslide ◽  
Southeastern Margin ◽  
Channel Slope ◽  
The One

AbstractLandslide dam outburst floods have a significant impact on landform evolution in high mountainous areas. Historic landslide dams on the Yigong River, southeastern Tibet, generated two outburst superfloods > 105 m3/s in 1902 and 2000 AD. One of the slackwater deposits, which was newly found immediately downstream of the historic dams, has been dated to 7 ka BP. The one-dimensional backwater stepwise method gives an estimate of 225,000 m3/s for the peak flow related to the paleo-stage indicator of 7 ka BP. The recurrence of at least three large landslide dam impoundments and super-outburst floods at the exit of Yigong Lake during the Holocene greatly changed the morphology of the Yigong River. More than 0.26 billion m3 of sediment has been aggraded in the dammed lake while the landslide sediment doubles the channel slope behind the dam. Repeated landslide damming may be a persistent source of outburst floods and impede the upstream migration of river knickpoints in the southeastern margin of Tibet.

scholarly journals State Management for Cloud-Native Applications

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 423
Author(s):  
Márk Szalay ◽  
Péter Mátray ◽  
László Toka
Keyword(s):  
Large Scale ◽  
Distributed Databases ◽  
Access Time ◽  
Replica Placement ◽  
State Management ◽  
Placement Decisions ◽  
Dynamic Replication ◽  
Cloud Databases ◽  
Placement Algorithm ◽  
The One

The stateless cloud-native design improves the elasticity and reliability of applications running in the cloud. The design decouples the life-cycle of application states from that of application instances; states are written to and read from cloud databases, and deployed close to the application code to ensure low latency bounds on state access. However, the scalability of applications brings the well-known limitations of distributed databases, in which the states are stored. In this paper, we propose a full-fledged state layer that supports the stateless cloud application design. In order to minimize the inter-host communication due to state externalization, we propose, on the one hand, a system design jointly with a data placement algorithm that places functions’ states across the hosts of a data center. On the other hand, we design a dynamic replication module that decides the proper number of copies for each state to ensure a sweet spot in short state-access time and low network traffic. We evaluate the proposed methods across realistic scenarios. We show that our solution yields state-access delays close to the optimal, and ensures fast replica placement decisions in large-scale settings.

scholarly journals Constructing Large-Scale Genetic Maps Using an Evolutionary Strategy Algorithm

Genetics ◽  
2003 ◽  
Vol 165 (4) ◽  
pp. 2269-2282
Author(s):  
D Mester ◽  
Y Ronin ◽  
D Minkov ◽  
E Nevo ◽  
A Korol
Keyword(s):  
Discrete Optimization ◽  
High Performance ◽  
Large Scale ◽  
Simulated Data ◽  
Real Data ◽  
Genetic Maps ◽  
Chromosome 1 ◽  
Evolutionary Strategy ◽  
Group A ◽  
The One

Abstract This article is devoted to the problem of ordering in linkage groups with many dozens or even hundreds of markers. The ordering problem belongs to the field of discrete optimization on a set of all possible orders, amounting to n!/2 for n loci; hence it is considered an NP-hard problem. Several authors attempted to employ the methods developed in the well-known traveling salesman problem (TSP) for multilocus ordering, using the assumption that for a set of linked loci the true order will be the one that minimizes the total length of the linkage group. A novel, fast, and reliable algorithm developed for the TSP and based on evolution-strategy discrete optimization was applied in this study for multilocus ordering on the basis of pairwise recombination frequencies. The quality of derived maps under various complications (dominant vs. codominant markers, marker misclassification, negative and positive interference, and missing data) was analyzed using simulated data with ∼50-400 markers. High performance of the employed algorithm allows systematic treatment of the problem of verification of the obtained multilocus orders on the basis of computing-intensive bootstrap and/or jackknife approaches for detecting and removing questionable marker scores, thereby stabilizing the resulting maps. Parallel calculation technology can easily be adopted for further acceleration of the proposed algorithm. Real data analysis (on maize chromosome 1 with 230 markers) is provided to illustrate the proposed methodology.

Global Reaction Model to Describe the Kinetics of Catalytic Pyrolysis of Coffee Grounds Waste

2017 ◽  
Vol 899 ◽  
pp. 173-178 ◽  
Author(s):  
Ronydes Batista Jr. ◽  
Bruna Sene Alves Araújo ◽  
Pedro Ivo Brandão e Melo Franco ◽  
Beatriz Cristina Silvério ◽  
Sandra Cristina Danta ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Large Scale ◽  
Catalytic Pyrolysis ◽  
Petroleum Products ◽  
Reaction Model ◽  
Heating Rates ◽  
Coffee Grounds ◽  
One Step ◽  
Global Reaction ◽  
The One

In view of the constant search for new sources of renewable energy, the particulate agro-industrial waste reuse emerges as an advantageous alternative. However, despite the advantages of using the biomass as an energy source, there is still strong resistance as the large-scale replacement of petroleum products due to the lack of scientifically proven efficient conversion technologies. In this context, the pyrolysis is presented as one of the most widely used thermal decomposition processes. The knowledge of aspects of chemical kinetics, thermodynamics these will, heat and mass transfer, are so important, since influence the quality of the product. This paper presents a kinetic study of slow pyrolysis of coffee grounds waste from dynamic thermogravimetric experiments (TG), using different powder catalysts. The primary thermal decomposition was described by the one-step reaction model, which considers a single global reaction. The kinetic parameters were estimated using nonlinear regression and the differential evolution method. The coffee ground waste was dried at 105°C for 24 hours. The sample in nature was analyzed at different heating rates, being 10, 15, 20, 30 and 50 K/min. In the catalytic pyrolysis, about 5% (w/w) of catalyst were added to the sample, at a heating rate of 30 K/min. The results show that the one-step model does not accurately represent the data of weight loss (TG) and its derivative (DTG), but can do an estimative of the activation energy reaction, and can show the differences caused by the catalysts. Although no one can say anything about the products formed with the addition of the catalyst, it would be necessary to micro-pyrolysis analysis, we can say the influence of the catalyst in the samples, based on the data obtained in thermogravimetric tests.

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