Fully coupled thermohydraulic modelling of the sealing bulkheads and adjacent rock in a full-scale underground test

2005 ◽  
Vol 42 (5) ◽  
pp. 1318-1329 ◽  
Author(s):  
Ruiping Guo ◽  
Jason Martino ◽  
David Dixon
Keyword(s):  
Pore Pressure ◽  
The United States ◽  
Measured Data ◽  
Second Phase ◽  
Two Phase ◽  
Physical Test ◽  
Thermally Induced ◽  
The Difference ◽  
Entrapped Air ◽  
Adjacent Rock

The Tunnel Sealing Experiment (TSX) was a two-phase international project funded by Canada, Japan, France, and the United States. The first phase was pressurizing the TSX chamber to 4 MPa to investigate the ability of clay and concrete bulkheads to reduce hydraulic flows. The second phase involved circulating heated water through the chamber to evaluate the influence of elevated temperature on the performance of the bulkheads and adjacent rock. A numerical analysis to simulate thermohydraulic evolution of the bulkheads and surrounding rock of the TSX was conducted to help in understanding the physical test process and the interaction between heat and pore pressure evolutions. The simulated rock temperature matched the measured data quite well; however the simulated bulkhead temperatures were greater than the measured temperatures. The difference may have been caused by entrapped air or formation of microchannels in the chamber sand, which would decrease the amount of heat reaching the bulkheads. The simulated thermally induced pore pressure increase in the clay bulkhead reasonably matched the measured data for the saturated portion. The difference in magnitude between simulated and measured rock pore pressures indicates that thermo hy draulic simulation should be coupled with a mechanical component when the stiffness of the media is large and hydraulic conductivity is low.Key words: numerical modelling, Tunnel Sealing Experiment, nuclear waste management, hydraulic head, thermal conduction, thermal convection.

scholarly journals Validation of Sexological Worldview

SAGE Open ◽  
2012 ◽  
Vol 2 (1) ◽  
pp. 215824401243907 ◽  
Author(s):  
Justin A. Sitron ◽  
Donald A. Dyson
Keyword(s):  
Attitude Change ◽  
Service Provision ◽  
Perspective Transformation ◽  
The United States ◽  
Qualitative Approach ◽  
Second Phase ◽  
Two Phase ◽  
Convenience Sample ◽  
Developmental Characteristics ◽  
Definition Of

The authors originally posited that a new construct must be developed to measure the success of affective training for sexologists, particularly the Sexuality Attitudes Reassessment (SAR) modality. Couching their critique in studies that have been conducted to measure the SAR’s effectiveness as a method used to evoke perspective transformation and more sensitive and humanistic service provision, the authors argued that the development of a professional’s sexological worldview would be a more accurate construct than attitude change to measure when considering the outcomes of SAR training. This study in the United States used a two-phase qualitative approach to validate the proposed sexological worldview construct. In the first phase, they surveyed a panel of 16 sexologists regarding their original proposed definition of sexological worldview and refined it. In the second phase, they completed 30 one-on-one interviews with a convenience sample of sexologists and sexology students. Using an inductive content analysis of the interview transcripts, seven themes emerged in support of the proposed definition of sexological worldview, including its components and its developmental characteristics. The article concludes with a discussion of the implications for the use of the construct for the training of sexologists.

scholarly journals Petrography of the Mesozoic Alkaline Rocks of the Taezhniy Massif (South Yakutia, Aldan-Stanovoy Shield, Leglier Ore Cluster)

2021 ◽  
Vol 906 (1) ◽  
pp. 012115
Author(s):  
Michil Ivanov ◽  
Aleksey Ivanov ◽  
Anatolii Zhuravlev
Keyword(s):  
The Body ◽  
Second Phase ◽  
Optical Studies ◽  
Two Phase ◽  
Small Bodies ◽  
The Difference ◽  
Two Phases ◽  
Host Rocks ◽  
Late Stages ◽  
Syenite Porphyry

Abstract The article is concerned with the petrographie compositions of the Mesozoic alkaline igneous rocks of the Taezhniy massif and its small bodies (dikes). The Taezhniy massif is located in the central part of the Nimnyr block (Aldan-Stanovoy shield). According to our field observations, it was first determined that the Taezhniy massif has a two-phase structure, its rocks of contain syenite-porphyry and leucocratic syenites. The rocks of the massif intrude the Archean granites, and are themselves intruded by late dikes of bostonites and vogesites. Based on petrographic studies, we also identified two phases of intrusion in the Taezhniy massif – syenite-porphyry and leucocratic syenites. The difference of them is as follows: in the syenite-porphyry rocks, plagioclase predominates over K-feldspar, and the content of dark-colored minerals reaches 10%. The rocks of the second phase are characterized by the predominance of K-feldspar over plagioclase, with the content of dark-colored minerals up to 5%. The order of intrusion of the massif formations is determined by the presence of xenoliths of syenite-porphyry rocks in leucocratic syenites. The rocks of the bostonite dike cutting the massif are characterized by the absence of amphibole and an increased content of pyroxene. This is most likely due to the fact that, the rock contains xenoliths of the host rocks of biotite-pyroxene composition. The dikes also conyain xenoliths of the second phase rocks, which indicates a later age of this dike. The bostonite dike located in the immediate vicinity of the massif is almost identical to the dike found in the massif, except an amphibole in the composition of the rocks. The only dike of vogesites that intersects the body of the massif is characterized by the presence of two varieties of amphibole: common hornblende and a sufficient amount of barkevikite, which phenocrysts stand out clearly against the background of the total microcrystalline mass. Also, in the course of crystal-optical studies, it was noted that in the structure of the massif there is an increase in the leucocratic magmatism from the early phase to the late, but with a decrease in this indicator, taking into account the introduction of vogesite dikes at the late stages of magmatism development. Based on this, the conclusion is made about the antidromic development of the rocks of the Taezhniy massif. When comparing the evolution of magmatism of the Taezhniy massif with the Ryabinoviy massif, a possible gold-ore specialization of the studied object is suggested.

Recent Advances on the Deformation Behavior of Two-Phase α+β Titanium Alloys

2019 ◽  
Vol 950 ◽  
pp. 55-59 ◽  
Author(s):  
Sreeramamurthy Ankem ◽  
William J. Joost ◽  
Samuel C. Schwarm
Keyword(s):  
Deformation Behavior ◽  
Single Phase ◽  
Elastic Interaction ◽  
Deformation Mechanisms ◽  
Second Phase ◽  
General Will ◽  
Two Phase ◽  
Ti Alloys ◽  
The Difference ◽  
The Individual

Two-phase materials, such as α+β Titanium (Ti) alloys, are technologically important. A number of factors can affect deformation behavior, including the interaction stresses between phases, the crystallographic relationships between phases, and the morphology. As a result, the deformation mechanisms of two-phase alloys may be different from the individual single-phase materials. For example, twinning may not occur in a single phase material if the grain size is very small but twinning can occur in a very fine grained alloy if the second phase contributes to the interfacial stresses due to elastic interactions. Interaction stresses can result from the difference in the elastic properties of the two phases. In particular, these elastic interaction stresses can be quantified by the finite element method (FEM). In this paper recent developments regarding two-phase deformation mechanisms will be reviewed and the ramifications on mechanical behavior in regard to two-phase Ti alloys in particular and on two-phase metallic materials in general will be outlined.

CORNER-DRIVEN COUPLED SQUARE LOOP ANTENNAS

1959 ◽  
Vol 37 (12) ◽  
pp. 1407-1417
Author(s):  
Sheila Prasad
Keyword(s):  
The Self ◽  
Second Phase ◽  
Two Phase ◽  
Mutual Impedance ◽  
First Order ◽  
Phase Sequence ◽  
Four Corners ◽  
The Difference ◽  
Loop Antennas ◽  
Independent Integral

A theory for two identical square loop antennas driven in the zeroth-phase sequence (voltages in phase at all four corners) and the second-phase sequence (voltages in and out of phase at the corners) is formulated. Eight independent integral equations are obtained. They are solved individually by the method of iteration, and first-order formulas are obtained for the current distributions and driving point impedances. For each phase sequence, the sum of the symmetrical and antisymmetrical impedances gives the self-impedance and the difference between them gives the mutual impedance. Self and mutual impedances are also obtained for a superposition of the two phase sequences.

Heavy Burdens: Ethical Issues Faced by Military Nurses during a War

2019 ◽  
Vol 24 (3) ◽  
Author(s):  
Deborah Kenny ◽  
Patricia Kelley
Keyword(s):  
Ethical Issues ◽  
The United States ◽  
Service Members ◽  
Background Information ◽  
Second Phase ◽  
Two Phase ◽  
Military Nurses ◽  
Military Nursing ◽  
Comprehensive Picture ◽  
The Many

American nurses have faced hardship and challenges in every war period in the relatively short history of the United States. This study was an in-depth reanalysis of a two-phase larger study of uniformed service nurses caring for service members injured in the conflicts in Iraq and Afghanistan. In this second phase, a qualitative descriptive study, 235 nurses and 67 wounded service members were interviewed in face-to-face discussions about their caring and care experiences. The article offers background information, discussion of the study methods, and presents some of the ethical issues faced by deployed nurses who were caring for the injured service members and injured/ill civilians during conflicts in Iraq and Afghanistan. Study findings revealed six themes that emerged directly from the data, providing a comprehensive picture of the many issues faced by these nurses. The stories of the nurses are used to illustrate many of their ethical dilemmas. We offer discussion with implications and recommendations for training and subsequent post-deployment care of these nurses. This article adds to the growing body of literature in the field of military nursing ethics.

scholarly journals Misfit-induced changes of lattice parameters in two-phase systems: coherent/incoherent precipitates in a matrix

2016 ◽  
Vol 49 (1) ◽  
pp. 69-77 ◽  
Author(s):  
Maryam Akhlaghi ◽  
Tobias Steiner ◽  
Sai Ramudu Meka ◽  
Eric Jan Mittemeijer
Keyword(s):  
Lattice Parameter ◽  
Current Treatment ◽  
Second Phase ◽  
Two Phase ◽  
Thermally Induced ◽  
Second Phase Particles ◽  
The Matrix ◽  
Phase Systems ◽  
The Individual ◽  
Multi Phase

Elastic accommodation of precipitation-induced or thermally induced misfit leads to lattice-parameter changes in crystalline multi-phase systems. Formulae for calculation of such misfit-induced lattice-parameter changes are presented for the aggregate (matrix + second-phase particles) and for the individual matrix and second phase, recognizing the occurrence of either coherent or incoherent diffraction by the matrix and second-phase particles. An overview and an (re)interpretation on the above basis is presented of published lattice-parameter data, obtained by X-ray diffraction analyses of aggregates of matrix plus second-phase particles. Examples for three types of systems consisting of a matrix with misfitting second-phase particles are dealt with, which differ in the origin of the misfit (precipitation or thermally induced) and in the type of diffraction (coherent or incoherent diffraction of matrix plus second-phase particles). The experimental data are shown to be in good to very good agreement with predictions according to the current treatment.

A Comparison of Tem and Apfim to the Interpretation of Modulated Microstructures

1985 ◽  
Vol 43 ◽  
pp. 70-71
Author(s):  
M.G. Burke ◽  
M.K. Miller
Keyword(s):  
Low Temperature ◽  
Microstructural Characterization ◽  
Superlattice Reflection ◽  
High Volume ◽  
Atom Probe ◽  
Dark Field ◽  
Miscibility Gap ◽  
Second Phase ◽  
Two Phase ◽  
Probe Field

Interpretation of fine-scale microstructures containing high volume fractions of second phase is complex. In particular, microstructures developed through decomposition within low temperature miscibility gaps may be extremely fine. This paper compares the morphological interpretations of such complex microstructures by the high-resolution techniques of TEM and atom probe field-ion microscopy (APFIM).The Fe-25 at% Be alloy selected for this study was aged within the low temperature miscibility gap to form a <100> aligned two-phase microstructure. This triaxially modulated microstructure is composed of an Fe-rich ferrite phase and a B2-ordered Be-enriched phase. The microstructural characterization through conventional bright-field TEM is inadequate because of the many contributions to image contrast. The ordering reaction which accompanies spinodal decomposition in this alloy permits simplification of the image by the use of the centered dark field technique to image just one phase. A CDF image formed with a B2 superlattice reflection is shown in fig. 1. In this CDF micrograph, the the B2-ordered Be-enriched phase appears as bright regions in the darkly-imaging ferrite. By examining the specimen in a [001] orientation, the <100> nature of the modulations is evident.

THE DYNAMIC FRACTURE OF TWO PHASE ALLOYS WITH SECOND PHASE INCLUSIONS

1985 ◽  
Vol 46 (C5) ◽  
pp. C5-251-C5-255
Author(s):  
S. Pytel ◽  
L. Wojnar
Keyword(s):  
Dynamic Fracture ◽  
Second Phase ◽  
Two Phase

Behaviour of air injection nozzles in dissolved air flotation

1995 ◽  
Vol 31 (3-4) ◽  
pp. 25-35 ◽  
Author(s):  
E. M. Rykaart ◽  
J. Haarhoff
Keyword(s):  
Bubble Coalescence ◽  
Second Phase ◽  
Initial Growth ◽  
Two Phase ◽  
Dissolved Air Flotation ◽  
Nozzle Orifice ◽  
Pressure Release ◽  
Air Volume ◽  
Air Flotation ◽  
Dissolved Air

A simple two-phase conceptual model is postulated to explain the initial growth of microbubbles after pressure release in dissolved air flotation. During the first phase bubbles merely expand from existing nucleation centres as air precipitates from solution, without bubble coalescence. This phase ends when all excess air is transferred to the gas phase. During the second phase, the total air volume remains the same, but bubbles continue to grow due to bubble coalescence. This model is used to explain the results from experiments where three different nozzle variations were tested, namely a nozzle with an impinging surface immediately outside the nozzle orifice, a nozzle with a bend in the nozzle channel, and a nozzle with a tapering outlet immediately outside the nozzle orifice. From these experiments, it is inferred that the first phase of bubble growth is completed at approximately 1.7 ms after the start of pressure release.

scholarly journals A novel two-phase cycle algorithm for effective cyber intrusion detection in edge computing

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Yiguang Gong ◽  
Yunping Liu ◽  
Chuanyang Yin
Keyword(s):  
Intrusion Detection ◽  
Optimal Parameter ◽  
Edge Computing ◽  
Cloud Services ◽  
Second Phase ◽  
Pareto Optimal ◽  
Two Phase ◽  
Multi Objective ◽  
Phase Cycle ◽  
Positive Rate

AbstractEdge computing extends traditional cloud services to the edge of the network, closer to users, and is suitable for network services with low latency requirements. With the rise of edge computing, its security issues have also received increasing attention. In this paper, a novel two-phase cycle algorithm is proposed for effective cyber intrusion detection in edge computing based on a multi-objective genetic algorithm (MOGA) and modified back-propagation neural network (MBPNN), namely TPC-MOGA-MBPNN. In the first phase, the MOGA is employed to build a multi-objective optimization model that tries to find the Pareto optimal parameter set for MBPNN. The Pareto optimal parameter set is applied for simultaneous minimization of the average false positive rate (Avg FPR), mean squared error (MSE) and negative average true positive rate (Avg TPR) in the dataset. In the second phase, some MBPNNs are created based on the parameter set obtained by MOGA and are trained to search for a more optimal parameter set locally. The parameter set obtained in the second phase is used as the input of the first phase, and the training process is repeated until the termination criteria are reached. A benchmark dataset, KDD cup 1999, is used to demonstrate and validate the performance of the proposed approach for intrusion detection. The proposed approach can discover a pool of MBPNN-based solutions. Combining these MBPNN solutions can significantly improve detection performance, and a GA is used to find the optimal MBPNN combination. The results show that the proposed approach achieves an accuracy of 98.81% and a detection rate of 98.23% and outperform most systems of previous works found in the literature. In addition, the proposed approach is a generalized classification approach that is applicable to the problem of any field having multiple conflicting objectives.

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