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Application of fuzzy methods in tunnelling  [PDF]
?udmila Tréfová,Edita Lazarová,Ví?azoslav Krúpa
Acta Montanistica Slovaca , 2011,
Abstract: Full-face tunnelling machines were used for the tunnel construction in Slovakia for boring of the exploratory galleries of highwaytunnels Branisko and Vi ňové-Dubná skala. A monitoring system of boring process parameters was installed on the tunnelling machinesand the acquired outcomes were processed by several theoretical approaches. Method IKONA was developed for the determination ofchanges in the rock mass strength characteristics in the line of exploratory gallery. Individual geological sections were evaluated bythe descriptive statistics and the TBM performance was evaluated by the fuzzy method. The paper informs on the procedure of the designof fuzzy models and their verification.
Properties of Black Hole Radiation From Tunnelling  [PDF]
Timothy Clifton
Physics , 2008, DOI: 10.1088/0264-9381/25/17/175022
Abstract: We consider the space-time associated with the evaporation of a black hole by quantum mechanical tunnelling events. It is shown that the surface through which tunnelling occurs is distinct from the global event horizon, and that this has consequences for the radiation reaching future null infinity. A spherical collapse process is modelled, and the radiation expected to be observed at future null infinity is calculated. It is shown that external observers witness an evaporation process that begins as the tunnelling surface is exposed, and ends as the collapsing object passes behind its event horizon. The sensitivity of emitted radiation to the collapse process is illustrated.
Hawking Radiation as Tunnelling in Static Black Holes  [PDF]
Wenbiao Liu
Physics , 2005,
Abstract: Hawking radiation can usefully be viewed as a semi-classical tunnelling process that originates at the black hole horizon. The conservation of energy implies the effect of self-gravitation. For a static black hole, a generalized Painleve coordinate system is introduced, and Hawking radiation as tunnelling under the effect of self-gravitation is investigated. The corrected radiation is consistent with the underlying unitary theory.
Tunnelling Effect and Hawking Radiation from a Vaidya Black Hole
REN Jun,ZHANG Jing-Yi,ZHAO Zheng,
任军
,张靖仪,赵峥

中国物理快报 , 2006,
Abstract: We extend Parikh's study to the non-stationary black hole. As an example of the non-stationary black hole, we investigate the tunnelling effect and Hawking radiation from a Vaidya black hole whose Bondi mass is identical to its mass parameter. The Hawking radiation is considered as a tunnelling process across the event horizon and we calculate the tunnelling probability. It is found that the is the function of Bondi mass re(υ). result is different from Parikh's study because dr H/dυ
Hawking radiation via tunnelling from general stationary axisymmetric black holes
Zhang Jing-Yi,Fan Jun-Hui,
张靖仪
,樊军辉

中国物理 B , 2007,
Abstract: Hawking radiation is viewed as a tunnelling process. In this way the emission rates of massless particles and massive particles tunnelling across the event horizon of general stationary axisymmetric black holes are calculated, separately. The emission spectra of these two different kinds of outgoing particles have the same functional form and both are consistent with an underlying unitary theory.
Climate Smart Agriculture: Achievements and Prospects in Africa  [PDF]
Adornis D. Nciizah, Isaiah I. C. Wakindiki
Journal of Geoscience and Environment Protection (GEP) , 2015, DOI: 10.4236/gep.2015.36016
Abstract:

Smallholder agriculture is facing a myriad of challenges in the wake of a changing climate. To counter this, several measures have been suggested in attempts to reduce the vulnerability of smallholder farmers who are the worst affected by changes in climate. However, despite these interventions not much improvement in agricultural production has been realized by the smallholder farmers. This suggests the need for more alternative options for these resource poor farmers. One such intervention is climate smart agriculture (CSA), which is probably one of the most viable and sustainable options. It offers both mitigation and adaptation measures to climate changes. However, problems of its viability and sustainability have been raised by several authors who argue that there are barriers, limits and costs, which may hinder its adoption by farmers. This review discusses the achievements attained so far in improving the productivity of smallholder agricultural soils under changing climatic conditions. The review also looks at the prospect of CSA with regards to South African smallholder agriculture.

New Coordinates for BTZ Black Hole and Hawking Radiation via Tunnelling  [PDF]
Wenbiao Liu
Physics , 2005, DOI: 10.1016/j.physletb.2006.01.028
Abstract: Hawking radiation can usefully be viewed as a semi-classical tunnelling process that originates at the black hole horizon. For the stationary axisymmetric BTZ black hole, a generalized Painleve coordinate system (Painleve-BTZ coordinates) is introduced, and Hawking radiation as tunnelling under the effect of self-gravitation is investigated. The corrected radiation is obtained which is not precise thermal spectrum. The result is consistent with the underlying unitary theory. Moreover, Bekenstein-Hawking entropy of BTZ black hole is not necessarily corrected when we choose appropriate coordinate system to study the tunnelling effect.
Tunnelling Effect and Hawking Radiation from a Vaidya Black Hole  [PDF]
Jun Ren,Jingyi Zhang,Zheng Zhao
Physics , 2006, DOI: 10.1088/0256-307X/23/8/016
Abstract: In this paper, we extend Parikh' work to the non-stationary black hole. As an example of the non-stationary black hole, we study the tunnelling effect and Hawking radiation from a Vaidya black hole whose Bondi mass is identical to its mass parameter. We view Hawking radiation as a tunnelling process across the event horizon and calculate the tunnelling probability. We find that the result is different from Parikh's work because $\frac{dr_{H}}{dv}$ is the function of Bondi mass m(v).
NMR Based Quantum Information Processing: Achievements and Prospects  [PDF]
D. G. Cory,R. Laflamme,E. Knill,L. Viola,T. F. Havel,N. Boulant,G. Boutis,E. Fortunato,S. Lloyd,R. Martinez,C. Negrevergne,M. Pravia,Y. Sharf,G. Teklemariam,Y. S. Weinstein,W. H. Zurek
Physics , 2000, DOI: 10.1002/1521-3978(200009)48:9/11<875::AID-PROP875>3.0.CO;2-V
Abstract: Nuclear magnetic resonance (NMR) provides an experimental setting to explore physical implementations of quantum information processing (QIP). Here we introduce the basic background for understanding applications of NMR to QIP and explain their current successes, limitations and potential. NMR spectroscopy is well known for its wealth of diverse coherent manipulations of spin dynamics. Ideas and instrumentation from liquid state NMR spectroscopy have been used to experiment with QIP. This approach has carried the field to a complexity of about 10 qubits, a small number for quantum computation but large enough for observing and better understanding the complexity of the quantum world. While liquid state NMR is the only present-day technology about to reach this number of qubits, further increases in complexity will require new methods. We sketch one direction leading towards a scalable quantum computer using spin 1/2 particles. The next step of which is a solid state NMR-based QIP capable of reaching 10-30 qubits.
The relation between Hawking radiation via tunnelling and the laws of black hole thermodynamics  [PDF]
Yapeng Hu,Jingyi Zhang,Zheng Zhao
Physics , 2006,
Abstract: In Parikh and Wilczek's original works, the laws of black hole thermodynamics are not referred and it seems that there is no relation between Hawking radiation via tunnelling and the laws of black hole thermodynamics in their works. However, taking examples for the R-N black hole and the Kerr black hole, we find that they are correlated and even consistent if the tunnelling process is a reversible process.
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