Littérature scientifique sur le sujet « Mohr Site »
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Articles de revues sur le sujet "Mohr Site"
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Han, Feng Shan. « Estimation of Strength of Massive Jointed Rock Mass Based on Generalized Hoek-Brown Criterion ». Applied Mechanics and Materials 204-208 (octobre 2012) : 259–62. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.259.
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The strength of massive jointed rock mass can be estimated based on Mohr-Coulomb criterion and Hoek-Brown criterion without making expensive experiment of massive jointed rock mass in site. Only using regression analysis, through transformation，Mohr-Coulomb criterion is compared with Hoek-Brown criterion, the strength of jointed rock mass can be economically obtained. In this paper, based on Geological Strength Index GSI and parameter Jv(Joint/m3), the strength of massive jointed rock mass can be obtained. As an example of GSI 24 for massive jointed rock mass is taken, generalized Hoek-Brown criterion is analyzed linearly and approximately using regression analysis, strength of jointed rock mass can be economically obtained That provide economical and effective method for practical engineering analysis
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Xiong, Yi Bo, Lu Peng, Jin Xu et Liang Ma. « Triaxial Compressive Behavior of Two Types of Concrete with Curing Conditions of Construction Site ». Advanced Materials Research 261-263 (mai 2011) : 38–42. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.38.
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Based on an extensive experimental program under uniaxial and triaxial compression, this paper studies the mechanical behavior of two types of concrete with the same raw materials and the same curing conditions of the construction site. Stress-strain relations and strengths are obtained under triaxial compression with confining pressures from 10MPa to 120MPa. Material constants of different types of failure criterion are determined by the statistical method with the data from this study and public literature, including linear Mohr-Coulomb model, parabolic Willam-Warnke failure criterion and power functional Johnson-Holmquist model. The results indicate that the modulus of both types of concrete decrease as an exponential decay law with the increase of confining pressures in triaxial compression.
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Kjaer, K. W. « A mutation in the receptor binding site of GDF5 causes Mohr-Wriedt brachydactyly type A2 ». Journal of Medical Genetics 43, no 3 (23 août 2005) : 225–31. http://dx.doi.org/10.1136/jmg.2005.034058.
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Chaverdi, Alireza Askari. « Post-Achaemenid Legacy of the Persian Gulf Hinterland ». Ancient Civilizations from Scythia to Siberia 23, no 1 (13 juillet 2017) : 127–50. http://dx.doi.org/10.1163/15700577-12341312.
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The archaeological site of Tomb-e Bot, located in the Mohr County of southern Fars Province, is a major settlement of Arsacid and Sasanid date. The site was selected for detailed investigation from among the 76 sites recorded by the general survey of southern Fars region to provide answers to outstanding questions on ancient Iran, in particular during the period from the Achaemenids to the Sasanids. The survey team systematically collected all visible architectural remains, including capitals with volutes and addorsed animal protomes as well as surface ceramics and attempted to draw and register the whole assemblage of finds. Documenting and analyzing the assemblage revealed that centuries after the Achaemenid demise the Persepolis artistic legacy had run on at the site in religious beliefs and among the local groups, from the Seleucid and Arsacid periods up to the rise of the Sasanids.
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Afolayan, David Oluwasegun, Adelana Rasak Adetunji, Azikiwe Peter Onwualu, Oghenerume Ogolo et Richard Kwasi Amankwah. « Characterization of barite reserves in Nigeria for use as weighting agent in drilling fluid ». Journal of Petroleum Exploration and Production Technology 11, no 5 (29 avril 2021) : 2157–78. http://dx.doi.org/10.1007/s13202-021-01164-8.
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AbstractSuccessful drilling operations are dependent on the properties of the drilling fluid used to drill wells. Barite is used as a weighting agent during the preparation of drilling fluid. Over the years, oil and gas industry in Nigeria has been depending mainly on imported barite for drilling operations, whereas the country has huge deposits of barite. There is the need to assess the properties of the locally sourced barite for their suitability in drilling fluid formulation. This study presents the local processing methods of barite and examines the crude and on-the-site processed barite’s physio-chemical properties. These parameters were compared with American Petroleum Institute and Department of Petroleum Resources standards. XRD results show that on-the-site beneficiated barite has 87.79% BaSO4, 6.66% silica, 0.03% total soluble salt, 1.39% Fe2O3, and 1.603% heavy metals. Chemical analysis indicated that the pH, moisture content, metallic content such as Ca, Pb, Zn, Mg, Cu, and Cd minerals, and extractable carbonates were within the standard specified for usage as a drilling fluid weighting agent. The analysed crude barite samples were basic, within the pH of 8.3 and 8.6. Locally processed barite has lower Fe, Pb, Cd, and Cu content compared to industrially accepted barite. The specific gravity increased from 4.02 ± 0.07 to 4.15 ± 0.13, and the hardness reduced potentially from 5 Mohr to 3.5 Mohr on the hardness scale. The amount of impurities was sufficiently low, and the specific gravity of the samples improved to meet the needs of any drilling operation and compare favourably with industrially accepted barite.
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Shukla, Madhulekha, et Sunita Arya. « DETERMINATION OF CHLORIDE ION(Cl-) CONCENTRATION IN GANGA RIVER WATER BY MOHR METHOD AT KANPUR, INDIA ». Green Chemistry & ; Technology Letters 4, no 1 (28 mars 2018) : 06–08. http://dx.doi.org/10.18510/gctl.2018.412.
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Purpose of the study:The purpose of this present study was determine the concentration of chloride ion in water sample which collected different site and season of river Ganga.Chloride ions in the environment can come from sodium chloride or from other chloride salts such as potassium chloride, calcium chloride and magnesium chloride.
Methodology:Water sample was collected from different site(Bithor ghat, Siddnath ghat and Dhoni ghat) and different season(Pre monsoon, Monsoon and post monsoon) of river Ganga from Kanpur in 2016-2018 year. Mohr method (Argentometric method) was a very simple and highly selective method for the determination of chloride ion (Cl-) using silver nitrate as the titrant.
Main Findings: In both the years 2016 till 2018, chloride concentration was within the limit at testing sites.
Applications of this study:To create awareness among the people to maintain the Ganga river water at its highest quality and purity levels.
Originality: This project was done in the D G P G College C S J M University, Kanpur India.
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Pan, Xing Yu, et Hong Yuan Fu. « Numerical Prediction of Settlement Adjacent to Deep Excavation of Metro Station in Ju-Zi-Zhou Island, Changsha ». Applied Mechanics and Materials 204-208 (octobre 2012) : 1484–87. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.1484.
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It is of great significant to predict the influence of deep excavation in Ju-Zi-Zhou island, so that damage to adjacent ancient tree, and Xiang-jiang Bridge could be prevented. Based on analysis of site condition, geological profile, and strut design, the numerical model was generated in commercial available software package Flac3D, in which Mohr-Coulomb model was introduced. Then, the settlements at several key points on the ground were evaluated in each step of excavation. The calibrated results shows that, the calculated settlement agrees well with the measured. So it can be applied to predict completed state and provide a guidance for next construction.
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Choi, Pom-yong, Jacques Angelier, Jean-Paul Cadet, Jae-Ha Hwang et Choon Sunwoo. « Change of stress magnitudes during the polyphase tectonic history of the Cretaceous Gyeongsang basin, southeast Korea ». Bulletin de la Société Géologique de France 184, no 4-5 (1 juillet 2013) : 467–84. http://dx.doi.org/10.2113/gssgfbull.184.4-5.467.
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Abstract In order to evaluate the change of stress magnitudes in the Gyeongsang basin during its tectonic history, we analyzed multiple faulting episodes in the Barremian-Aptian Hasandong Formation at the Yusu site. As elsewhere in southeast Korea, the recorded sequence consists of a succession of more than fourteen faulting episodes, and the relative chronology shows that a strike-slip faulting episode usually coexisted with a coaxial extensional episode. Likewise, seven couples of synchronous coaxial episodes recognised in the Gyeongsang basin are assigned to seven tectonic events (T_1 to T_7 events). The friction line (in the sense of Byerlee) allows us to determine the ratios between principal stress magnitudes as well as the origin of the dimensionless Mohr diagram. This line can be deduced from tension fractures on fault planes affected by friction and from the lower limit of scattered distribution of the normal stresses vs. shear stresses of faults. Dimensionless failure envelopes drawn for coaxial strike-slip and extensional episodes are adjusted to the experimental Mohr failure envelope derived from rock mechanic tests to determine the complete stress tensors. The maximum principal stress magnitudes of strike-slip episodes show a transition from 169 MPa in the Barremian-Coniacian T_1 Event through 263 MPa and 246 MPa in the T_2 and T_4 events, respectively to 235 MPa in the Quaternary T_7 Event; additional horizontal extension (ΔσT) have changed from −6 MPa in the T_1 Event through −8 MPa in the T_2 Event to −17 MPa in the T_7 Event. Because the studied site is currently exposed, the determined overburden (1.9 km) for the T_7 Event seems to be important, indicating the presumable occurrence of this event during the early Quaternary rather than at the present day.
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Agraine, Hana, et Meriem Fakhreddine Bouali. « Numerical Modelling of Oedometer Test ». Selected Scientific Papers - Journal of Civil Engineering 15, no 2 (1 décembre 2020) : 127–36. http://dx.doi.org/10.1515/sspjce-2020-0025.
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Abstract The oedometric test is a test widely used in civil engineering. The main objective of this article has been to investigate the primary consolidation behaviour of the intact soil samples by comparing the results obtained from finite element analysis computations in PlAXIS2D with the experimental result of the soil samples obtained from the site of the Al-Ahdab oil field in the east of Iraq. Three different material models were utilized during the finite element analysis, comparing the performance of the more advanced constitutive Soft Soil material model against the modified Cam Clay and Mohr-Coulomb material models. Numerical results of Oedomter test show that the Soft Soil model behaviour is the most appropriate model to describe the observed behaviour.
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Zhou, Xiaojie, Qinghua Liang, Yueyu Zhang, Zhongxian Liu et Ying He. « Three-Dimensional Nonlinear Seismic Response of Immersed Tunnel in Horizontally Layered Site under Obliquely Incident SV Waves ». Shock and Vibration 2019 (24 juillet 2019) : 1–17. http://dx.doi.org/10.1155/2019/3131502.
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A three-dimensional (3D) detailed numerical model of an immersed tunnel in a horizontally layered site is established in this study. The 3D seismic response of the immersed tunnel in a horizontally layered site subjected to obliquely incident waves is analyzed based on the precise dynamic stiffness matrix of the soil layer and half-space via combined viscous-spring boundary and equivalent node stress methods. The nonlinear effects of external and internal site conditions on the whole model were determined by equivalent linearization algorithm and Mohr–Coulomb model, respectively. The proposed model was then applied to investigate the nonlinear seismic response of an immersed tunnel in the Haihe River subjected to seismic waves of oblique incidence. The dislocation (opening) of pipe joints in the immersed tunnel were analyzed to determine the response characteristics of the shear keys and overall displacement of the tunnel; the dynamic responses of the immersed tunnel subjected to obliquely incident seismic waves markedly differ from those of vertically incident seismic SV waves. The maximum stress value of shear keys and the maximum dislocation of the pipe joint appear as upon critical angle. The overall displacement of the tunnel increases as incident angle increases. Under severe earthquake conditions, both the pipe corners and midspan section of the roof and floor are likely to produce crack. These areas need careful consideration in the seismic design of immersed tunnel structures.
Thèses sur le sujet "Mohr Site"
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Glah-Donahue, Lisa Lynn. « The Role of Pottery in Shenks Ferry Mortuary Features at the Mohr Site ». Master's thesis, Temple University Libraries, 2010. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/104882.
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AnthropologyM.A.
Using the Mohr Site as a case study, this project examines the role of pottery in Shenks Ferry mortuary features. Following an analysis of the mortuary pottery, the resulting information is compared with pottery from the general site assemblage as well as with descriptions of pottery from other Shenks Ferry sites. In addition, an inventory of the Mohr Site grave good assemblage has been created. The assemblage at the Mohr site is especially rich and is particularly noteworthy given the nature and number of the burials discovered; no other current collection has as much variety or quantity as is seen at this site. The pottery recovered from Mohr exhibits characteristics typical of pottery found at other Shenks Ferry Sites and in other Shenks Ferry burials. The ceramic evidence challenges the traditional assumption that the Mohr site is a transitional Lancaster-Funk Phase site. Likewise, the length of time this site was occupied is also debatable. Mortuary vessels at Mohr are predominately associated with extended burials oriented to the east. There are also correlations between mortuary vessels types and age and sex. Possible connections between other grave goods and age, sex, and body position and between body position and season of interment are also discussed. Additional research employing methods such as residue analysis to compare information regarding the contents of the mortuary and non-mortuary Mohr Site pottery as well as further evidence produced by additional excavations or more in-depth analysis of current grave material collections will provide further insight into Shenks Ferry mortuary ritual and is necessary in order to fully understand this site and its place in the chronology of the Shenks Ferry Complex.
Temple University--Theses
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Zimmerli, Stephan. « Vegetation und Standort von Schwingrasen in der Schweiz = Vegetation and site condition of floating mats in Switzerland / ». Zürich : Geobotanisches Institut der ETH, 1988. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=8701.
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Mohr, Susanne [Verfasser], Joerg [Akademischer Betreuer] Libuda, Andreas [Gutachter] Görling et Joerg [Gutachter] Libuda. « In-situ IRAS Studies of Small Organic Molecules on Metal and Metal Oxide Surfaces / Susanne Mohr ; Gutachter : Andreas Görling, Joerg Libuda ; Betreuer : Joerg Libuda ». Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2019. http://d-nb.info/120214599X/34.
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Hjalmarsson, Marie, et Linda Jensen. « Kvinnors upplevelse av att separeras från sitt barn efter förlossningen då barnet behöver vård på en neonatalavdelning ». Thesis, Högskolan i Borås, Institutionen för Vårdvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-19858.
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Av de barn som föds i Sverige behöver cirka 10 % vård eller övervakning på en neonatalavdelning. Detta kan leda till försening i kontakten med modern och ett ömsesidigt samspel kan störas.Syftet med denna studie är att beskriva hur kvinnor upplever det att separeras från sitt barn efter förlossningen då barnet behöver vård på en neonatalavdelning. Sex stycken kvinnor har intervjuats. En kvalitativ metod har valts, inspirerad av fenomenologisk livsvärldsansats och analyserad med en kvalitativ innehållsanalys.Resultatet presenteras i fem kategorier som beskriver upplevelsen av att separeras från sitt barn efter förlossningen. Dessa kategorier är: Att inte vara medveten, Att sakna kraft, Rädsla och oro för barnets hälsa, Att lämna över sitt barn i någon annans händer samt Att inte få vara nära sitt barn.Då barnet behövde vård på en neonatalavdelning uttryckte kvinnorna i studien ett lidande som präglades av rädsla över barnets hälsa. Brist på information om barnets tillstånd gav begränsad insikt i situationen som ledde till känslor av maktlöshet. Då barnets tillstånd snabbt kunde förändras kastades kvinnorna mellan hopp och förtvivlan och kämpade därmed med anknytningsprocessen. De funderade på om den tidiga separationen med barnet skulle påverka anknytningen dem emellan. Att kunna amma sitt barn skänkte dock en tillfredställelse som gav kvinnorna hopp. Kvinnorna fick inte möjlighet att vårdas på samma avdelning som sina barn vilket fick dem att känna sig stressade och kraftlösa. Om avdelningarna varit placerade intill varandra uttryckte flera kvinnor att separationen hade upplevts mindre negativ.Kärnan i resultatet visar framför allt på den oro de nyblivna mammorna känner för sitt barns hälsa samt sorgen över att inte få ge barnet sin värme och närhet i den utsträckning hon skulle vilja.Program: Barnmorskeutbildning
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Okunomiya, Taro. « Generation of a MOR-CreER knock-in mouse line to study cells and neural circuits involved in mu opioid receptor signaling ». Kyoto University, 2020. http://hdl.handle.net/2433/253202.
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Kögler, Felix [Verfasser], Dirk [Akademischer Betreuer] Schulze-Makuch, Hakan [Akademischer Betreuer] Alkan, Nicole [Akademischer Betreuer] Dopffel, Foppe [Akademischer Betreuer] Visser, Dirk [Gutachter] Schulze-Makuch, Thomas [Gutachter] Neumann et Mohd [Gutachter] Amro. « Opportunities and challenges for in situ, fermentation-based microbial enhanced oil recovery (MEOR) in a high-salinity oilfield / Felix Kögler ; Gutachter : Dirk Schulze-Makuch, Thomas Neumann, Mohd Amro ; Dirk Schulze-Makuch, Hakan Alkan, Nicole Dopffel, Foppe Visser ». Berlin : Technische Universität Berlin, 2020. http://d-nb.info/121816008X/34.
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Wendel, Dirk. « Autogene Regenerationserscheinungen in erzgebirgischen Moorwäldern und deren Bedeutung für Schutz und Entwicklung der Moore ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-67943.
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- Ziele der Arbeit - Ziel vorliegender Arbeit ist, zu analysieren und zu beurteilen, in welchem Umfang autogene Moorregeneration nach anthropogenen Störungen auftritt, welche Voraussetzungen sie erfordert und welche Prozesse von Bedeutung sind. Forstliche und naturschutzfachliche Relevanz der Erkenntnisse sind zu prüfen. - Versuchsanlage und Methoden - Die Versuchsanlage umfasst verschiedene räumliche Skalenebenen und Zeitabschnitte. Im Untersuchungsraum sächsisches Erzgebirge befinden sich fünf Untersuchungsgebiete. Geschichtliche Aspekte werden auf Basis von Recherchen, der aktuelle Moorzustand anhand von Geländeerhebungen zu Vegetation und Standort analysiert. Langzeitbeobachtungen dienen dem Nachweis von Sukzessionsprozessen und den sie beeinflussenden Umweltfaktoren. Regenerationsprozesse werden anhand von Regenerationsmerkmalen, die eigens für diese Zwecke erarbeitet wurden, lokalisiert und im Kontext mit dem aktuellen Moorzustand und den Erfordernissen von Naturschutz und Forstwirtschaft interpretiert. - Ergebnisse und Schlussfolgerungen - - Das Aufnahmematerial lässt die Differenzierung von 28 Vegetationstypen zu, die anhand von Artengruppen und Zeigerwerten charakterisiert und als Kartiereinheiten zur Bewertung der Moore verwendet werden. Die Moorfläche im Untersuchungsraum wird auf 8.500 ha geschätzt. Jedes untersuchte Moor weist eine spezifische Kombination abiotischer sowie biotischer Merkmale auf und ist deshalb individuell zu bewerten. Entwässerungen und Torfstiche führen zu starker Degeneration, Dominanz von Wald, Seltenheit moortypischer Pflanzenarten, Offengesellschaften, nässegeprägter hydromorphologischer Strukturen sowie ökosystemrelevanter Schlüsselarten. Hinzu kommt eine Schädigung der Baum- und Moosschicht durch SO2-Immissionen bis in die 1990er Jahre und eine nachfolgende Regeneration. - Wiedervernässungen durch Graben- und Torfstichverlandung sind anhand von Zeitreihen und aktuellen Regenerationsmerkmalen nachweisbar. Autogene Moorregeneration kommt selbst in stark degenerierten Mooren vor. Regenerationsbereiche sind häufig, erreichen aber nur einen geringen Anteil an der Moorfläche (Untersuchungsraum: 1 %, Untersuchungsgebiete: 12 %). Sie haben meist mesotrophen Charakter. Eine erhöhte Regenerationsdisposition tritt u. a. bei konvergenten Wasserströmen und geringen Neigungen auf. Lokale Prozesse wie die Bildung von Fließhindernissen beeinflussen das Unwirksamwerden von Gräben. Die Etablierung torfbildender Vegetation nimmt eine Schlüsselstellung ein. Verschiedene Stufen eines diskontinuierlichen Regenerationsfortschritts sind zu unterscheiden und in bisher bekannte Prozessabläufe einzuordnen. Häufigkeit und Flächenverhältnis initialer und fortgeschrittener Regeration legen nahe, dass Regenerationsprozesse auf größerer Fläche ablaufen, jedoch nicht erkannt werden. Regeneration führt zu Standortsdrift und Ausbreitung moortypischer Arten. Das Regenerationspotenzial ist abiotisch vorgegeben. Irreversible Veränderungen der hydromorphologischen Struktur durch Entwässerung oder Torfabbau setzen der Regeneration Grenzen. Anthropogene Stoffeinträge und Mangel an Schlüsselarten bewirken weitere Einschränkungen. - Soweit eine rentable Holzproduktion Ziel ist, stellen autogen regenerierende Moore schwer bis nicht bewirtschaftbare Standorte dar, die aufgrund von Standortsdrift und teils Gehölzfeindlichkeit ein hohes Produktionsrisiko bergen. Naturschutzfachlich sind Regenerationsprozesse eine Chance und ein bedeutendes Schutzgut, da sie zu höherwertigeren Moorlebensräumen führen. Bei fortgeschrittener Regeneration erübrigen sich kostenintensive Eingriffe. Ein statischer Schutz wird dem Prozesscharakter nicht gerecht. Initialstadien und Bereiche, die noch nicht regenerieren, aber ein hohes Potenzial aufweisen, lassen sich effizient fördern. Die starke Degeneration der Moore im Untersuchungsraum begründet bei geringem Anteil aktueller Regenerationsbereiche einen hohen Handlungsbedarf, einschließlich eines abschirmenden Schutzes sowie effizienter Kontrollmechanismen. - Geeignete Datengrundlagen zur Lokalisierung von Flächen mit einem hohen Regenerationspotenzial fehlen weitgehend. Eine Behebung dieses Defizits ist möglich- Objectives - The objective of this work is to analyse and to assess to which extent autogenous peatland regeneration occurs after anthropogenic disturbances, what preconditions it requires and what processes are important. Relevance of the findings for forestry and nature conservation is to be examined. - Experimental set-up and methods - The experimental set-up comprises various spatial scale levels and time periods. Five study sites are located in the study area Saxon Erzgebirge Mountains. Historical aspects are analysed based on investigations, the actual condition of the peatland is determined by ground surveys focusing on the vegetation and the site. Long-term observations serve to prove succession processes and the environmental factors influencing them. Regeneration processes are localized by means of regeneration characteristics, which were elaborated just for this purpose, localized, and interpreted in the context of the actual peatland condition and of the requirements of nature conservation and forestry. - Results and conclusions - - The material under survey allows distinguishing between 28 vegetation types which are characterised by means of species groups and indicator values and which are used as mapping units for evaluating the peatlands. The peatland area in the study area comprises an estimated 8500 ha. Each investigated peatland has a specific combination of abiotic and biotic characteristics and therefore needs to be evaluated individually. Drainage and peat cuttings lead to strong degeneration, dominance of forest, rarity of plants species typical of peatland, open-land associations, wetness-coined hydromorphological structures as well as ecosystem-relevant key species. In addition, the tree and moss layer had been damaged by SO2-pollution up to the 1990ies and a succeeding regeneration. - Recurring wetting due to filling-up of ditches and peat cuttings by sedimentation are verifiable by time sequences and actual regeneration characteristics. Autogenous peatland regeneration occurs even in heavily degenerated peatlands. Regeneration areas are frequent, accounting, however, only for a small share at the peatland area (study area: 1 %, study sites: 12 %). Often they are of mesotrophic nature. An increased disposition to regeneration is found, among others, in case of convergent water flows and slight inclinations. Local processes like the formation of obstacles for the flowing may cause ditches to become ineffective. Establishing of peat-forming vegetation is a crucial phenomenon. Various stages of a discontinuous regeneration progress can be differentiated and allocated to the processes that are known so far. Frequency and the area ratio of initial and progressed regeneration suggest that regeneration processes take place on a larger area, but that they are not recognised. Regeneration leads to site drifting and the distribution of peatland species. The regeneration potential is given by abiotic conditions. Irreversible changes of the hydro-morphological structure due to drainage or peat cutting are limiting factors for the regeneration. Anthropogenic input of matter and lack of key species bring about other restrictions. - If a profitable timber production is aimed at, autogenously regenerated peatlands are sites difficult to manage or that cannot be managed at all, involving a high production risk due to site drifting and partly inadequacy for woody plants. For nature conservation, regeneration processes are a chance and an important asset worth of protection, as they lead to high-grade peatland habitats. In the case of advanced regeneration cost-intensive operations are not necessary. A protection of static nature is inadequate for the process character. Initial stages and zones not yet under regeneration, implying, however, a high potential, can be promoted efficiently. Heavy degeneration of the peatlands in the study area, given a low proportion of actual regeneration zones, justifies a strong call for action, including a shielding protection as well as efficient control mechanisms. - An appropriate data basis for localisation of areas, having a high regeneration potential, is largely missing. Remedying this deficit is possible
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Pache, Gilles. « Les humus forestiers du massif de la Chartreuse : de l'approche macro-écologique à l'approche micro-écologique ». Université Joseph Fourier (Grenoble ; 1971-2015), 1998. http://www.theses.fr/1998GRE10122.
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Le type d'humus que l'on peut observer sous foret resulte d'interactions nombreuses et complexes entre les conditions abiotiques (facteurs physiques et chimiques de l'environnement) et les facteurs biotiques (communautes vegetales, animales, fongiques et microbiennes). C'est en milieu montagnard (massif de la chartreuse), ou ces interactions sont mal connues, que nous avons etudies le determinisme et le fonctionnement des differents types d'humus a deux echelles de perception. A petite echelle (approche stationnelle), on observe un lien etroit entre la morphologie des humus et la repartition des especes vegetales. Cette morphologie est surtout dependante des facteurs physiques de l'environnement (bilan hydrique, aeration). A grande echelle, une etude du fonctionnement de quatre humus (deux mulls, un mor, et un tangel), correspondant a deux niveaux d'activite biologique tranches et a deux contextes edaphiques chimiques varies (acide et neutre), a ete menee. Le microclimat au sol des deux mulls differe de ceux du mor et du tangel par une xericite moindre, ceci etant essentiellement du a la vegetation herbacee tres differente. L'humidite edaphique est egalement plus elevee dans les deux humus de type mull (notamment grace a des apports par ruissellement). L'activite biologique (essentiellement lombricienne), tres superieure dans les deux mull, temoigne des conditions physiques favorables dans les deux mull, la xericite dans le tangel, et l'anoxie dans le mor, limitant cette activite.
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Simonsson, Rakel, et Marcus Söderberg. « Att överleva sitt barn : Upplevelser av psykisk hälsa hos föräldrar vars barn genomfört suicid : ett systematiskt litteraturstudium ». Thesis, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34678.
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SAMMANFATTNING Bakgrund: Enligt WHO begås årligen cirka 800 000 självmord av människor världen över. I Sverige år 2012 begick 1151 personer suicid. Att förlora ett barn kan medföra en försämrad psykisk hälsa som följd. Studien har vårdvetenskapen som teoretisk referensram med fokus på hälsa, lidande och människan både som individ och del av en helhet. Syfte: Syftet är att beskriva upplevelsen av psykisk hälsa hos föräldrar vars barn genomfört suicid. Metod: Systematisk litteraturstudium med latent innehållsanalys av sex kvalitativa och två kvantitativa artiklar. Resultat: Resultatet presenteras i tre teman: Den utlämnade människan, den lidande människan och den förnyande människan. Frekvent förekom känslor av skuld, maktlöshet, utanförskap och svårigheter att gå vidare i livet, självdestruktiva tankar och handlingar, ångest, depression och sorg. Även glimtar där föräldrar lyckats finna hopp, tröst och stöd återfinns i resultatet. Konklusion: Föräldrar som förlorat ett barn genom suicid upplever i stor utsträckning försämrad psykisk hälsa. Resultatet visade att över tid förbättrades den psykiska hälsan hos flera föräldrar. Somliga hjälps av att ha stöd av andra, andra av att ge stöd medan ytterligare andra behövde stillhet och avskildhet. Den stora variation som resultatet uppvisar indikerar att ett individbaserat bemötande behöver praktiseras.
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Wendel, Dirk. « Autogene Regenerationserscheinungen in erzgebirgischen Moorwäldern und deren Bedeutung für Schutz und Entwicklung der Moore ». Doctoral thesis, 2010. https://tud.qucosa.de/id/qucosa%3A25564.
Texte intégralRésumé :
- Ziele der Arbeit -
Ziel vorliegender Arbeit ist, zu analysieren und zu beurteilen, in welchem Umfang autogene Moorregeneration nach anthropogenen Störungen auftritt, welche Voraussetzungen sie erfordert und welche Prozesse von Bedeutung sind. Forstliche und naturschutzfachliche Relevanz der Erkenntnisse sind zu prüfen.
- Versuchsanlage und Methoden -
Die Versuchsanlage umfasst verschiedene räumliche Skalenebenen und Zeitabschnitte. Im Untersuchungsraum sächsisches Erzgebirge befinden sich fünf Untersuchungsgebiete. Geschichtliche Aspekte werden auf Basis von Recherchen, der aktuelle Moorzustand anhand von Geländeerhebungen zu Vegetation und Standort analysiert. Langzeitbeobachtungen dienen dem Nachweis von Sukzessionsprozessen und den sie beeinflussenden Umweltfaktoren. Regenerationsprozesse werden anhand von Regenerationsmerkmalen, die eigens für diese Zwecke erarbeitet wurden, lokalisiert und im Kontext mit dem aktuellen Moorzustand und den Erfordernissen von Naturschutz und Forstwirtschaft interpretiert.
- Ergebnisse und Schlussfolgerungen -
- Das Aufnahmematerial lässt die Differenzierung von 28 Vegetationstypen zu, die anhand von Artengruppen und Zeigerwerten charakterisiert und als Kartiereinheiten zur Bewertung der Moore verwendet werden. Die Moorfläche im Untersuchungsraum wird auf 8.500 ha geschätzt. Jedes untersuchte Moor weist eine spezifische Kombination abiotischer sowie biotischer Merkmale auf und ist deshalb individuell zu bewerten. Entwässerungen und Torfstiche führen zu starker Degeneration, Dominanz von Wald, Seltenheit moortypischer Pflanzenarten, Offengesellschaften, nässegeprägter hydromorphologischer Strukturen sowie ökosystemrelevanter Schlüsselarten. Hinzu kommt eine Schädigung der Baum- und Moosschicht durch SO2-Immissionen bis in die 1990er Jahre und eine nachfolgende Regeneration.
- Wiedervernässungen durch Graben- und Torfstichverlandung sind anhand von Zeitreihen und aktuellen Regenerationsmerkmalen nachweisbar. Autogene Moorregeneration kommt selbst in stark degenerierten Mooren vor. Regenerationsbereiche sind häufig, erreichen aber nur einen geringen Anteil an der Moorfläche (Untersuchungsraum: 1 %, Untersuchungsgebiete: 12 %). Sie haben meist mesotrophen Charakter. Eine erhöhte Regenerationsdisposition tritt u. a. bei konvergenten Wasserströmen und geringen Neigungen auf. Lokale Prozesse wie die Bildung von Fließhindernissen beeinflussen das Unwirksamwerden von Gräben. Die Etablierung torfbildender Vegetation nimmt eine Schlüsselstellung ein. Verschiedene Stufen eines diskontinuierlichen Regenerationsfortschritts sind zu unterscheiden und in bisher bekannte Prozessabläufe einzuordnen. Häufigkeit und Flächenverhältnis initialer und fortgeschrittener Regeration legen nahe, dass Regenerationsprozesse auf größerer Fläche ablaufen, jedoch nicht erkannt werden. Regeneration führt zu Standortsdrift und Ausbreitung moortypischer Arten. Das Regenerationspotenzial ist abiotisch vorgegeben. Irreversible Veränderungen der hydromorphologischen Struktur durch Entwässerung oder Torfabbau setzen der Regeneration Grenzen. Anthropogene Stoffeinträge und Mangel an Schlüsselarten bewirken weitere Einschränkungen.
- Soweit eine rentable Holzproduktion Ziel ist, stellen autogen regenerierende Moore schwer bis nicht bewirtschaftbare Standorte dar, die aufgrund von Standortsdrift und teils Gehölzfeindlichkeit ein hohes Produktionsrisiko bergen. Naturschutzfachlich sind Regenerationsprozesse eine Chance und ein bedeutendes Schutzgut, da sie zu höherwertigeren Moorlebensräumen führen. Bei fortgeschrittener Regeneration erübrigen sich kostenintensive Eingriffe. Ein statischer Schutz wird dem Prozesscharakter nicht gerecht. Initialstadien und Bereiche, die noch nicht regenerieren, aber ein hohes Potenzial aufweisen, lassen sich effizient fördern. Die starke Degeneration der Moore im Untersuchungsraum begründet bei geringem Anteil aktueller Regenerationsbereiche einen hohen Handlungsbedarf, einschließlich eines abschirmenden Schutzes sowie effizienter Kontrollmechanismen.
- Geeignete Datengrundlagen zur Lokalisierung von Flächen mit einem hohen Regenerationspotenzial fehlen weitgehend. Eine Behebung dieses Defizits ist möglich.- Objectives - The objective of this work is to analyse and to assess to which extent autogenous peatland regeneration occurs after anthropogenic disturbances, what preconditions it requires and what processes are important. Relevance of the findings for forestry and nature conservation is to be examined. - Experimental set-up and methods - The experimental set-up comprises various spatial scale levels and time periods. Five study sites are located in the study area Saxon Erzgebirge Mountains. Historical aspects are analysed based on investigations, the actual condition of the peatland is determined by ground surveys focusing on the vegetation and the site. Long-term observations serve to prove succession processes and the environmental factors influencing them. Regeneration processes are localized by means of regeneration characteristics, which were elaborated just for this purpose, localized, and interpreted in the context of the actual peatland condition and of the requirements of nature conservation and forestry. - Results and conclusions - - The material under survey allows distinguishing between 28 vegetation types which are characterised by means of species groups and indicator values and which are used as mapping units for evaluating the peatlands. The peatland area in the study area comprises an estimated 8500 ha. Each investigated peatland has a specific combination of abiotic and biotic characteristics and therefore needs to be evaluated individually. Drainage and peat cuttings lead to strong degeneration, dominance of forest, rarity of plants species typical of peatland, open-land associations, wetness-coined hydromorphological structures as well as ecosystem-relevant key species. In addition, the tree and moss layer had been damaged by SO2-pollution up to the 1990ies and a succeeding regeneration. - Recurring wetting due to filling-up of ditches and peat cuttings by sedimentation are verifiable by time sequences and actual regeneration characteristics. Autogenous peatland regeneration occurs even in heavily degenerated peatlands. Regeneration areas are frequent, accounting, however, only for a small share at the peatland area (study area: 1 %, study sites: 12 %). Often they are of mesotrophic nature. An increased disposition to regeneration is found, among others, in case of convergent water flows and slight inclinations. Local processes like the formation of obstacles for the flowing may cause ditches to become ineffective. Establishing of peat-forming vegetation is a crucial phenomenon. Various stages of a discontinuous regeneration progress can be differentiated and allocated to the processes that are known so far. Frequency and the area ratio of initial and progressed regeneration suggest that regeneration processes take place on a larger area, but that they are not recognised. Regeneration leads to site drifting and the distribution of peatland species. The regeneration potential is given by abiotic conditions. Irreversible changes of the hydro-morphological structure due to drainage or peat cutting are limiting factors for the regeneration. Anthropogenic input of matter and lack of key species bring about other restrictions. - If a profitable timber production is aimed at, autogenously regenerated peatlands are sites difficult to manage or that cannot be managed at all, involving a high production risk due to site drifting and partly inadequacy for woody plants. For nature conservation, regeneration processes are a chance and an important asset worth of protection, as they lead to high-grade peatland habitats. In the case of advanced regeneration cost-intensive operations are not necessary. A protection of static nature is inadequate for the process character. Initial stages and zones not yet under regeneration, implying, however, a high potential, can be promoted efficiently. Heavy degeneration of the peatlands in the study area, given a low proportion of actual regeneration zones, justifies a strong call for action, including a shielding protection as well as efficient control mechanisms. - An appropriate data basis for localisation of areas, having a high regeneration potential, is largely missing. Remedying this deficit is possible.
Livres sur le sujet "Mohr Site"
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Zimmerli, Stephan. Vegetation und Standort von Schwingrasen in der Schweiz = : Vegetation and site conditions of floating mats in Switzerland. [Zürich : Geobotanisches Institut der ETH, Stiftung Rübel,], 1988.
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Melaka, Universiti Teknikal Malaysia. Citra dua hati satu inspirasi : Tun Dr. Mahathir Mohamad & Tun Dr. Siti Hasmah Mohd. Ali. Melaka, Malaysia : Universiti Teknikal Malaysia Melaka, 2009.
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C, Bergen, Niekus, M. J. L. Th., Vilsteren V. T. van et Provinciaal Museum van Drenthe, dir. Der Tempel im Moor. 2e éd. Zwolle : Waanders, 2002.
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Jejak seorang pemimpin sejarah lisan Tun Dr. Siti Hasmah Mohd Ali. Petaling Jaya, Selangor, Malaysia : MPH Group Publishing Sdn Bhd, 2014.
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Johnson, Nicholas, Desmond Bonney et Peter Rose. Bodmin Moor Vol. 2 : An Archaeological Survey. Historic England Publishing, 2008.
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Parker, A. An Assessment of the Extent of Contamination by Mustard at a Site on Bowes Moor, Co. Durham. AEA Technology Plc, 1987.
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Andreas, Bauerochse, Hassmann Henning et Püschel Klaus, dir. "Moora" - das Mädchen aus dem Uchter Moor : Eine Moorleiche der Eisenzeit aus Niedersachsen. Rahden, Westf : Verlag Marie Leidorf, 2008.
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James, David. The designation of areas as Sites of Special Scientific Interest - some problems with particular reference to Flitwick Moor. 1986.
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Majlis konvokesyen komemoratif : Sempena penganugerahan ijazah kehormat doktor ekonomi kepada Yang Amat Berbahagia Tun Dr. Mahathir bin Mohamad dan ijazah kehormat doktor falsafah (pembangunan sosial) kepada Yang Amat Berbahagia Tun Dr. Siti Hasmah bte Mohd. Ali. Kota Kinabalu : Universiti Malaysia Sabah, 2004.
Trouver le texte intégralChapitres de livres sur le sujet "Mohr Site"
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McLeod, Michael P., Katlein França, Sonal Choudhary, Yasser A. Alqubaisy et Keyvan Nouri. « Side to Side Closure After Mohs Surgery ». Dans Mohs Micrographic Surgery, 443–46. London : Springer London, 2011. http://dx.doi.org/10.1007/978-1-4471-2152-7_35.
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Chan, Lawrence S. « Mohs Micrographic Surgery sine Microscopy ». Dans New Technologies in Dermatological Science and Practice, 107–18. Boca Raton : CRC Press, 2021. http://dx.doi.org/10.1201/9781003121275-11.
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Kunishige, Joy, et John Zitelli. « Mohs Surgery for Melanoma In Situ ». Dans Melanoma, 323–35. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-78310-9_18.
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Aasi, Sumaira Z., David J. Leffell et Rossitza Z. Lazova. « Squamous Cell Carcinoma In Situ and Actinic Keratoses ». Dans Atlas of Practical Mohs Histopathology, 153–78. New York, NY : Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-5161-7_9.
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Jiménez García, Marilisa. « Nicholasa Mohr Writes Back ». Dans Side by Side, 109–45. University Press of Mississippi, 2021. http://dx.doi.org/10.14325/mississippi/9781496832474.003.0004.
Texte intégralRésumé :
This chapter analyzes Nicholasa Mohr as a voice for those children of the Puerto Rican diaspora, born and raised in New York, who felt increasingly out of touch with the island described in Belpré’s folklore. Mohr underlines children’s literature as of utmost importance in terms of searching for representation in an imagined literary landscape. Here, through readings of Nilda (1973) and El Bronx Remembered (1975), this chapter shows how Mohr resists established Puerto Rican and Anglo iconography which had been established in children’s literature by the 1970s.
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« NICHOLASA MOHR WRITES BACK : ». Dans Side by Side, 109–45. University Press of Mississippi, 2021. http://dx.doi.org/10.2307/j.ctv1j55h06.8.
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« Mohs Scale ». Dans Size Reduction of Divided Solids, 169–71. Elsevier, 2016. http://dx.doi.org/10.1016/b978-1-78548-185-7.50010-2.
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Brontë, Charlotte. « Chapter IV ». Dans Jane Eyre. Oxford University Press, 2019. http://dx.doi.org/10.1093/owc/9780198804970.003.0034.
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The more I knew of the inmates of Moor House, the better I liked them. In a few days I had so far recovered my health that I could sit up all day, and walk out sometimes. I could join with Diana and Mary...
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Mohd Nazri Wan Abdul Rahman, Wan, Nur Sakinah Mohamed Tamat, Nor Yuziah Mohd Yunus et Jamaludin Kasim. « Size Effect of Core Strands on the Major Physical and Mechanical Properties of Oriented Strand Boards from Fast Growing Tropical Species ». Dans Engineered Wood Products for Construction [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99953.
Texte intégralRésumé :
Oriented strand board (OSB) is generally used for sheathing in residential walls, floors, and roofs. Because of its low pricing and utilisation of tiny diameter logs from fast-growing trees and thinning logs as raw materials, OSB is anticipated to gain popularity. In chapter, board properties of OSB using smaller strand size of Leucaena leucocephala as core layer had been studied. Small strand size of S3 (length = 75 mm, width = 3.2 to 6.3 mm) was located in the middle layer of the board while bigger strand sizes of S1 (length = 75 mm, width = 12.7 to 19.0 mm) and S2 (length = 75 mm, width = 6.3 to 12.7 mm) were located at the face and back layers. Utilization of smaller strands (S3) in the middle layers may yield boards that have better physical and mechanical properties. Except for MOR in the minor axis, board density and resin content were shown to have a substantial impact on physical and mechanical properties. Except for MOR in the major axis, strand size had little affected on physical and mechanical properties. The effects of board density on mechanical properties were discovered to affect significantly different. With a positive correlation, board density had a significant effect on thickness swelling. Between S1+S3 and S2+S3 strand size, there is no significant effect on bending properties, internal bond strength and thickness swelling. The effect of resin content on bending properties revealed a significant difference of MOR in major axis, as well as MOE values in both major and minor axes. Even when the resin content was as low as 5%, all treatments of OSB passed the general requirement of general purpose OSB.
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Rassios, Anne Ewing, Dina Ghikas, Anna Batsi, Petros Koutsovitis, Evangelos Tzamos et Yildirim Dilek. « Internal lithospheric rotation at the initiation of intra-oceanic rift-drift : An example of proto-transform tectonics from the Vourinos Ophiolite, Greece ». Dans Plate Tectonics, Ophiolites, and Societal Significance of Geology : A Celebration of the Career of Eldridge Moores. Geological Society of America, 2021. http://dx.doi.org/10.1130/2021.2552(04).
Texte intégralRésumé :
ABSTRACT The “petrological Moho” recognized in the Jurassic Vourinos Ophiolite (northern Greece) was the first “crust-mantle” boundary described within a fossil oceanic lithosphere. Early observations suggested a Cenozoic brittle-field block rotation of the petrological Moho transition area resulting in an oblique clockwise rotation of ∼100°, but a brittle fault system responsible for the mechanism of this rotation was never located. A modern interpretation of research dating from the 1960s to the present documents the occurrence of a diverse set of ductile structures overprinting this primary intra-oceanic feature. The following observations from our original “Moho” studies in the Vourinos complex are still pertinent: the contact between the upper mantle units and the magmatic crustal sequence is in situ and intrusional in nature; high-temperature intragranular ductile deformation (mantle creep at temperatures from around 1200 °C down to ∼900 °C) fabrics terminate at the crust-mantle boundary; the overlying oceanic crustal rocks display geochemical fractionation patterns analogous to crustal rocks in the in situ oceanic lithosphere. Since these original studies, however, understanding the mechanisms of ductile deformation and ridge crest processes have advanced, and hence we can now interpret the older data and recent observations in a new paradigm of oceanic lithosphere formation. Our major interpretational breakthrough includes the following phenomena: lower temperature, intergranular deformation of ∼900 °C to 700 °C extends from the upper mantle tectonites up into the lower crustal cumulate section; the origin of mineral lineations within adcumulate crustal rocks as remnants of ductile deformation during early phases of magmatic crystallization; syn-magmatic folding and rotation of the cumulate section; the tectonic significance of flaser gabbro and late gabbroic intrusions in the crustal sequence; and the relevance and significance of a cumulate troctolite unit within the crustal sequence. These observations collectively point to an important process of a ductile-field, syn-magmatic rotation of the Moho transition area. The most plausible mechanism explaining such a rotation is proto-transform faulting deformation near the ridge crest. By recognizing and distinguishing structures that resulted from such initial rotational deformation in the upper mantle peridotites of ophiolites, future field-based structural, petrographic, and petrological studies can better document the mode of the initiation of oceanic transform faults.
Actes de conférences sur le sujet "Mohr Site"
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Gharabaghi, A. R. M., A. Arablouei, A. Ghalandarzadeh et K. Abedi. « The Dynamic Response of Gravity Type Quay Wall During Earthquake Including Soil-Sea-Structure Interaction ». Dans 25th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/omae2006-92313.
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The dynamic response of gravity type quay wall during earthquake including soil-sea-structure interaction is calculated using ADINA finite element techniques. The main objective of this study is to investigate the effects of fluid-structure interaction on the residual displacement of wall after a real earthquake. A direct symmetric coupled formulation based on the fluid velocity potential is used to calculate the nonlinear hydrodynamic pressure of sea water acting on the wall. The doubly asymptotic approximation (DAA) is used to account for the effects of outer fluid on the inner region. The non-associated Mohr-Coulomb material behavior is applied to model the failure of soil. The full nonlinear effective stress analysis is performed in this study and the soil-pore fluid interaction effects are modeled using porous media formulation. Viscous boundary condition is implemented to model the artificial boundary in direct method analysis of soil-structure interaction system and sliding contact condition was modeled in the interface of wall and surrounding soil. A typical configuration of gravity quay wall is used for analysis and three real earthquakes excitation are applied as base acceleration. The results show that influence of fluid-structure interaction effects on the permanent displacement of a gravity quay wall constructed on relatively non-liquefiable site is not considerable.
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Qiu, Gang, Ju¨rgen Grabe, Nikolai Kukolka et Hans-Werner Vollstedt. « Numerical Studies of Installation and Extraction Processes of Jack-Up Ships ». Dans ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49928.
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New Jack-up ships are built to transport offshore wind turbines from harbor and assemble them with the help of cranes on the ship at the site of installation. Every ship has four stilts, which can be lowered to seabed and jack the ship up. However, penetration and extraction the stilts at the harbor area could jeopardize the existing quay wall construction. In this paper two conceptual designs of foundations, which are used to improve the strength of the seabed in front of the quay wall, are investigated using numerical methods. Through soil exchange in open-ended cylinder or bucket foundation the strength of the seabed should be improved so that jack-up ships can dock directly at the quay wall and lower the stilts into the foundations. Three dimensional finite element analysis using a coupled Eulerian-Lagrangian method (CEL) are carried out to simulate penetration and extraction process. A hypoplastic constitutive model and the Mohr-Coulomb constitutive model are used to describe the filling. The studies of influences of geometry of foundations as well as the soil parameters on the bearing capacity of stilts and failure mechanism in foundations are carried out as the design basis of the foundations.
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Chen, Pengchao, Shibin Zhang, Shimei Yang, Zhengbin Li et Yanguang Ren. « Pipeline Material Strain Monitoring System in Permafrost of MoHe-DaQing Pipeline ». Dans 2012 9th International Pipeline Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ipc2012-90293.
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Mohe-Daqing pipeline is the first pipeline to be buried, passing through the permafrost regions of North China where the temperature in winter is about minus thirty degrees Celsius. This pipeline has been transporting large quantities of crude oil per day to northern markets of China since January 1st, 2011. It’s a significant cooperation for both Russia and China. This paper reviews the design, construction, and operational challenges of the first pipeline buried in the permafrost regions of North China. The pipeline is in so complicated geography environment that many kinds of geotechnical disaster could happen easily, including frost heave, thaw settlement, slope instabilities, and collapse and so on. Monitoring pipeline material strain in specific region is important and significant. Ground movement of the pipeline induces sufficiently large strains to the pipeline, which would cause wrinkling on the compression side of the pipe, or alternatively tensile fracture on the tensile side of the pipe. Brag fiber sensors have been located and composed on the surface of the pipe, which were used to monitor material strain real-time data at any time. Finite element pipe soil interaction and ground movement models in specific sites have been developed according to the monitoring data. Whether the generated pipeline strain is exceeded the strain capacity or not could be estimated by comparing with the strain capacity of the pipeline, which can help us to make decision for pipeline safety management and prevent pipeline damage from geotechnical disaster.
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Xing, Haoyuan, Gagan Agrawal et Rajiv Ramnath. « MoHA : A Composable System for Efficient In-Situ Analytics on Heterogeneous HPC Systems ». Dans SC20 : International Conference for High Performance Computing, Networking, Storage and Analysis. IEEE, 2020. http://dx.doi.org/10.1109/sc41405.2020.00086.
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Sheng, Feng, et Dan Jiao. « A Minimal Order Model From Zero to High Frequencies for Finite-Element Based Analysis of General 3-D Electromagnetic Problems ». Dans ASME 2013 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ipack2013-73177.
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Modern integrated circuits (IC) and package design has scaled into the deep submicron regime and the nanometer regime. Fast and broadband frequency-domain electromagnetic analysis has become increasingly important. The large problem size encountered in the analysis of ICs and packages is a major challenge especially for a finite element method (FEM) based electromagnetic analysis. To reduce the computational cost for large-scale electromagnetic analysis, model order reduction (MOR) methods have been developed to preprocess the huge linear system into reduced order models. However, in order to meet the modeling and simulation challenges arising from the IC and package design, existing MOR methods still have to overcome the following shortcomings. First, many existing MOR methods lack a closed-form error bound. Given an accuracy requirement, the model generated from existing methods may not be compact enough. Second, most of the existing reduced order models depend on frequency and right hand side. They lose efficiency when analyzing frequency-dependent problems with a large number of right hand sides. Last but not least, many existing MOR methods suffer from low frequency breakdown problem. Additional models have to be built if low frequency solutions, including DC solution, are required. This paper proposes a minimal order model for any prescribed accuracy for the finite element based solution of general 3-D problems having arbitrary lossless/lossy structures and inhomogeneous materials. This model entails no theoretical approximations. It is frequency and right hand side independent, and hence can be employed for both fast frequency and right hand side sweep. Moreover, the model does not suffer from low-frequency breakdown and is accurate from zero to high frequencies. To facilitate the application of such a minimal order model, we have also developed an efficient algorithm to generate this model. Numerical experiments have demonstrated the accuracy and efficiency of the proposed method. In addition to frequency-domain analysis, the proposed model can also be used for fast time-domain analysis.
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Kaneshima, Takuma, Fuqiao Bai et Nobuo Morita. « Comprehensive Analysis of Borehole Stability with Temperature, Swelling, and Pore Pressure Change for Layered and Orthotropic Formations ». Dans SPE/IADC International Drilling Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204068-ms.
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Abstract Borehole stability depends on various parameters such as rock strength, rock deformations, in-situ stress, borehole trajectory, shale swelling, pore pressure change due to osmosis, overbalance mud weight and temperature. The objective of this work is to construct analytical and numerical equations to predict borehole failure including all these parameters, and to comprehensively propose a methodology to improve the borehole stability. Analytical solutions are developed for inclined wells with respect to in-situ stress, shale swelling, pore pressure change due to osmosis, overbalance mud weight and temperature. A numerical model is developed for 3D inclined wells with orthotropic formation and layered formation. Using the analytical and the numerical models, stress state around inclined wells are evaluated. The breakout angle is predicted based on Mohr-Coulomb, Mogi, Lade and Drucker-Prager failure theories. Polar diagrams of mud weights are compared to judge the effect of each parameter and the magnitude predicted by the different failure theories. Shale swelling and pore pressure change due to osmosis are the most difficult to estimate among above-mentioned parameters. The laboratory measured swelling of cores obtained from various formations showed that the magnitude to induce breakouts caused by swelling was the largest comparing with other parameters. Therefore, when shale stability problems occur, we need to estimate the magnitude of shale swelling and osmosis due to water potential difference. Then, to overcome the shale stability problem, we evaluated the sensitivity of human controllable parameters on borehole stability. The parameters which can be controlled by drilling engineers are overbalance, type of mud, borehole temperature and borehole trajectory. If the shale swelling is small, the borehole stability is improved by the mud weight. However, from the swelling tests from the cores of Nankai-Trough, we estimated unless we used a swelling inhibitor to reduce the swelling less than 0.1%, the well was not possible to drill through. Actually, the well was abandoned due to instability after trying side track several times. Unlike previous works, this paper uses all important parameters (swelling, temperature, pore pressure, orthotropic formation, layered formation) to estimate the stresses around inclined wells with the same formation conditions for quantitative analysis. Failure analysis include Mohr, Mogi, Lade and Drucker-Prager. Finally, the polar diagrams of critical mud weight are used to judge whether we can choose well trajectory, orientation with respect to bedding planes, mud weight, shale inhibitor, and temperature to stabilize the borehole.
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Namba, Yasuhiro, Masanori Kyo et Eigo Miyazaki. « Technical Challenges for Mantle Drilling ». Dans ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-78217.
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Mantle drilling, in which the oceanic crust is penetrated across the Moho to retrieve mantle samples, is one of the most challenging scientific projects of this century. This paper presents a literature survey on the development of mantle drilling, provides a brief introduction to mantle drilling, and introduces three drilling site candidates. Obstacles to mantle drilling are then presented, along with current R&D activities, plans, and considerations for solving those problems. For the purposes of this paper, significant contributions in mantle drilling research have been classified into the following categories: ultra-deep water, deep penetration, hard rocks, and high temperature. Necessary future research directions for mantle drilling are also described.
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Roy, Kshama, Bipul Hawlader, Shawn Kenny et Ian Moore. « A Comparative Study Between Lateral and Upward Anchor-Soil and Pipe-Soil Interaction in Dense Sand ». Dans 2016 11th International Pipeline Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ipc2016-64546.
Texte intégralRésumé :
Buried pipelines are extensively used in onshore and offshore environments for transportation of hydrocarbons. On the other hand, buried anchors have been used for many years to stabilize various structures. In the development of design guidelines for pipelines, theoretical and experimental studies on buried anchors are sometimes used assuming that pipeline-soil and anchor-soil interaction are similar. In the present study, finite element (FE) modeling is performed to simulate the response of pipeline and anchor buried in dense sand subjected to lateral and uplift forces. The similarities and differences between the responses of these two types of structures are examined to justify the application of anchor theory to pipeline behaviour. The stress-strain behaviour of dense sand is modeled using a Modified Mohr-Coulomb (MMC) model, which considers the pre-peak hardening, post-peak softening, density and confining pressure dependent friction and dilation angles. A considerable difference is found between the lateral resistance of pipeline and vertical strip anchor of similar size. Progressive development of shear bands (shear strain concentrated zone) can explain the load-displacement behaviour for both lateral and upward loading.
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Lin, Meng, Yong Li, Mohammad Salem, J. J. Roger Cheng, Samer Adeeb et Muntaseer Kainat. « A Parametric Study of Variable Crack Initiation Criterion in XFEM on Pipeline Steel ». Dans ASME 2020 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/pvp2020-21664.
Texte intégralRésumé :
Abstract The integrity decisions for cracked pipelines can be made based on the conventional Finite Element Method (FEM). However, it is extremely time-consuming due to the requirement of remeshing to continuously conform to the geometric discontinuities as the crack propagates. The more recently developed Extended Finite Element Method (XFEM) provides a more robust approach in which a crack can propagate through the finite element analysis mesh and thus alleviates the requirement for remeshing. However, the current criteria for crack initiation and propagation in XFEM framework have not been calibrated to pipeline steels. The current built-in criterion in Abaqus assumes a fixed value as the damage strain. Crack initiation occurs after this strain is exceeded. However, the accuracy of numerical crack propagating path is questionable, especially in a side-grooved single edge notched tension (SENT) model. Faster crack initiation at specimen side over the center conflicts with the actual crack propagating path obtained from a physical test. This paper develops a new crack initiation criterion which defines a variable damage strain as a function of the stress configuration at the crack tip. The criterion is modified from the Mohr-Coulomb fracture criterion as a function of stress triaxiality and Lode angle parameters. The damage strain exponentially decreases as the stress triaxiality increases. This paper presents a parametric study on the effects of material parameters considered in the criterion on the development of damage strain locus. The new crack initiation criterion is applied to a side-grooved SENT model, in which the corresponding failure mechanism is defined by the user’s subroutine UDMGINI in Abaqus.
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Yu, Long, Hui Zhou, Wen Gao, Jun Liu et Yuxia Hu. « Spudcan Penetration in Clay-Sand-Clay Soils ». Dans ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49316.
Texte intégralRésumé :
Multi-layered soil conditions often exist in offshore practice. In some sites a thin layer of medium dense sand lays between firm to stiff clay layers. In these cases the ultimate bearing capacity of foundations can be increased due to the strong sand layer by comparing with foundations in uniform clay. However, there is also a potential of reduction in foundation capacity when the foundation punches through the sand layer. The punch-through failure can occur during either pre-loading or storm loading. In this study, the continuous penetration of spudcan foundations on clay-sand-clay soils was investigated by large deformation finite element analysis. The numerical simulation was carried out using Remeshing and Interpolation Technique with Small Strain (RITSS) model. The clays obey Tresca failure criterion for undrained analysis and the sands obey Mohr-Coulomb yield criterion for drained analysis. The friction angle of the sand was taken as φ = 32° and 40° with its dilation angle ψ = 2° and 10° respectively. The effects of the relative height of the top soft clay and the relative thickness of the middle sand layer on the load-displacement responses were investigated. The soil flow mechanisms at various penetration depths were also discussed.