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SIMULATION OF HYDRAULIC FRACTURE NETWORKS IN THREE DIMENSIONS
Full text linkABSTRACT Hydraulic fracturing has been an enabling technology for commercially stimulating fracture networks for over half of a century. It has become one of the most widespread technologies for engineering subsurface fracture systems. Despite the ubiquity of this technique in the field, understanding and prediction of the hydraulic induced propagation of the fracture network in realistic, heterogeneous reservoirs has been limited. Recent developments allowing the modeling of complex fracture propagation and advances in quantifying solution uncertainties, provide the possibility of capturing both the fracturing behavior and longer term permeability evolution of rock masses under hydraulic loading across both dynamic and viscosity dominated regimes. We present a framework for leveraging these advances in practical workflows for analyzing prospective and operating geothermal / hydrothermal sites. We will demonstrate the first phase of this effort through illustrations of fully three-dimensional, 2-way coupled hydromechanical simulations of hydraulically induced fracture network propagation and discuss preliminary results regarding the mechanisms by which fracture interactions and the accompanying changes to the stress field can lead to deleterious or beneficial changes to the fracture network
FREQUENCY AND LENGTH ADJUSTMENT OF A DUMBBELL FOR THE PEFP LOW-BETA SRF CAVITY*
Full text linkAbstract This paper describes a method to adjust the frequency and the length of a dumbbell used to fabricate the PEFP low-beta superconducting RF cavity. A tuning program is used to calculate the π mode frequency of each half-cell according to the resonant frequency of a TM010 passband and the perturbation frequency shifts of a dumbbell. According to the frequency difference between the two half cells and the frequency sensitivity coefficients, we can determine the tuning length in the axial direction or the trimming length at the equator to make the two half cells have the same frequency and length. In order to measure the frequency and to compensate for the length of a PEFP dumbbell for a stiffening-ring welding shrinkage, a frequency measurement set and length tuning set have been fabricated
THE ECTOMYCORRHIZAL FUNGUS TRICHOLOMA MATSUTAKE IS CAPABLE OF FACULTATIVE SAPROTROPHY
Full text linkABSTRACT We studied carbon acquisition in Tricholoma matsutake by combining morphological, chemical and enzymatic experiments conducted both in the laboratory and natural setting. Associations between host plants and isolates of T. matsutake from Finland (2) and Japan (1) were confirmed via in vitro formation of ectomycorrhizae (ECM). Chemical properties and enzyme-activity rates were determined for samples of mycelia-soil aggregation (shiro) collected from sites of sporocarp formation and nearby control spots. Annual growth and seasonal changes in tissue and ECM health were monitored in a natural population of matsutake. Finally, several organic substrates were evaluated as the sole carbon source for T. matsutake growing in vitro and according to the most active enzymes in the shiro. Matsutake formed typical ECM with the conifers Pinus sylvestris and Picea abies but did not form associations with Silver Birch (Betula pendula). Finnish isolates formed ECM on both conifers but the Japanese strain was less compatible, with only a partial Hartig net being observed in P. sylvestris. Saprotrophic feeding of the Japanese isolate was observed in culture with P. abies. Preferred organic carbon sources and enzyme activities in vitro corresponded to those observed in the shiro. Enzyme assays confirmed the presence and increased production of organic carbon degradation related enzymes during sporocarp formation, when ECM root tips were necrotic. Mycelial growth on culture media consisting of complex polysaccharides was similar to that composed of simple sugars (e.g., glucose). In addition to its typical life strategy as an ECM symbiont, results suggest that T. matsutake can exist as a saprotroph
DOES A LESS ACTIVE CENTRAL BANK LEAD TO GREATER ECONOMIC STABILITY? EVIDENCE FROM THE EUROPEAN MONETARY UNION
Full text linka Preferential Dopamine D 3 versus D 2 Receptor Antagonist and Potential Antipsychotic Agent. II. A Neurochemical, Electrophysiological and Behavioral Characterization in Vivo
Full text linkABSTRACT The novel benzopyranopyrrolidine, S33138 [N-[4-[2-[(3aS,9bR)-8-cyano-1,3a,4,9b-tetrahydro Article, publication date, and citation information can be found a
Epidemiology and Infection Additional services for Epidemiology and Infection: Email alerts: Click here Subscriptions: Click here Commercial reprints: Click here Terms of use : Click here First encounter of European bat lyssavirus type 2 (EBLV2) in a bat
No full textUnderstanding the physics of bungee jumping
Full text linkAbstract Changing mass phenomena like the motion of a falling chain, the behaviour of a falling elastic bar or spring, and the motion of a bungee jumper surprise many a physicist. In this article we discuss the first phase of bungee jumping, when the bungee jumper falls, but the bungee rope is still slack. In instructional material this phase is often considered a free fall, but when the mass of the bungee rope is taken into account, the bungee jumper reaches acceleration greater than g. This result is contrary to the usual experience with free falling objects and therefore hard to believe for many a person, even an experienced physicist. It is often a starting point for heated discussions about the quality of the experiments and the physics knowledge of the experimentalist, or it may even prompt complaints about the quality of current physics education. But experiments do reveal the truth and students can do them supported by information and communication technology (ICT) tools. We report on a research project done by secondary school students and use their work to discuss how measurements with sensors, video analysis of self-recorded high-speed video clips and computer modelling allow study of the physics of bungee jumping
Modeling Age-Friendly Environment, Active Aging, and Social Connectedness in an Emerging Asian Economy
Full text linkThis paper empirically tested eight key features of WHO guidelines to age-friendly community by surveying 211 informal caregivers and 402 self-care adults (aged 45 to 85 and above) in Malaysia. We examined the associations of these eight features with active aging and social connectedness through exploratory and confirmatory factor analyses. A structural model with satisfactory goodnessof-fit indices (CMIN/df = 1.11, RMSEA = 0.02, NFI = 0.97, TLI = 1.00, CFI = 1.00, and GFI = 0.96) indicates that transportation and housing, community support and health services, and outdoor spaces and buildings are statistically significant in creating an age-friendly environment. We found a statistically significant positive relationship between an age-friendly environment and active aging. This relationship is mediated by social connectedness. The results indicate that built environments such as accessible public transportations and housing, affordable and accessible healthcare services, and elderly friendly outdoor spaces and buildings have to be put into place before social environment in building an age-friendly environment. Otherwise, the structural barriers would hinder social interactions for the aged. The removal of the environmental barriers and improved public transportation services provide short-term solutions to meet the varied and growing needs of the older population
uallitative Reasoning at Multi
Full text linkAh §tI%Nt In this paper we describe an approach to unify the various quantity spaces that have been proposed in qualitative reasoning with numbers. We work in the domain of physical devices, such as electrical circuits using lumped parameter models. We show how changing the quantity space can be achieved in the course of analysis and how this is similar to dynamically changing the resolution in analysis. We demonstrate the utility of this approach with two examples in the domain of circuit analysis
Circuital and Numerical Modeling of Electrostatic Discharge Generators Spartaco Caniggia
Full text linkAbstract-The paper provides two accurate and efficient models of electrostatic discharge (ESD) generators which permit to reproduce the discharge current in the contact mode taking into account the load effect. The first model is based on a circuit approach and is suitable to be implemented in any commercial circuit simulator. The second model is based on the numerical solution of the field equations by using the commercial numerical code Microwave Studio (MWS) based on the finite integration technique. The validation of the proposed circuit and numerical models is carried out by comparison with measurements