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Appendix 1
Abstract Samples
Abstract Sample 1
Vincent D Blondel, Guillaume, J. L. & Lambiotte R. (2008, October 9). Fast unfolding of communities in large networks. Journal of Statistical Mechanics: Theory and Experiment . Retrieved December 1,2017 from http://iopscience.iop.org/article/10.1088/1742-5468/2008/10/P10008/pdf
Abstract.
We propose a simple method to extract the community structure of large networks. Our method is a heuristic method that is based on modularity optimization. It is shown to outperform all other known community detection methods in terms of computation time. Moreover, the quality of the communities detected is very good, as measured by the so-called modularity. This is shown first by identifying language communities in a Belgian mobile phone network of 2 million customers and by analyzing a web graph of 118 million nodes and more than one billion links. The accuracy of our algorithm is also verified on ad hoc modular networks.
Keywords.
Random graphs; Networks new applications of statistical mechanics.
Abstract Sample 2
Froidevaux, D. & Mitsou, V. A. (2009). Experimental prospects at the Large Hadron Collider. Journal of Physics:Conference Series ,171(1). Retrieved December 1, 2017 from http://iopscience.iop.org/article/10.1088/1742-6596/171/1/012021/pdf
Abstract .
This review focuses on the expected performance of the ATLAS and CMS detectors at the CERN Large Hadron Collider (LHC), together with some of the highlights of the global commissioning work done in 2008 with basically fully operational detectors. A selection of early physics measurements, expected to be performed with the data taken in 2009/2010 is included for completion, together with a brief reminder of the ultimate physics potential of the LHC.
Abstract Sample 3
Chepel, V. & Araújo, H. (2013, April 8). Liquid noble gas detectors for low energy particle physic. Journal of Instrumentation , 8. Retrieved December 1, 2017 from https://arxiv.org/pdf/1207.2292
Abstract .
We review the current status of liquid noble gas radiation detectors with energy threshold in the keV range, which are of interest for direct dark matter searches, measurement of coherent neutrino scattering and other low energy particle physics experiments. Emphasis is given to the operation principles and the most important instrumentation aspects of these detectors, principally of those operated in the double-phase mode. Recent technological advances and relevant developments in photon detection and charge readout are discussed in the context of their applicability to those experiments.
Keywords.
Neutrino detectors; Noble-liquid detectors (scintillation, ionization two-phase, Dark Matter detectors (WIMPs, axions, etc.); Charge transport, multiplication and electroluminescence in rare gases and liquids.
Abstract Sample 4
Beeman, J. W., Bellini, F., Casali, N. et al . (2013, July 30).Characterization of bolometric light detectors for rare event searches. Journal of Instrumentation,8. Retrieved December 1, 2017 from http://iopscience.iop.org/article/10.1088/1748-0221/8/07/P07021/pdf
Abstract .
Bolometers have proven to be very good detectors to search for rare processes thanks to their excellent energy resolution and their low intrinsic background. Further active background rejection can be obtained by the simultaneous readout of the heat and light signals produced by particles interacting in scintillating bolometers, as proposed by the LUCIFER experiment. In this framework, the choice of the light detector and the optimization of its working conditions play a crucial role. In this paper, we report a study of the performances of a Germanium bolometric light detector in terms of signal amplitude, energy resolution and signal time development. The impact of various operational parameters on the detector performances is discussed.
Keywords.
Solid state detectors; Gamma detectors (scintillators, CZT, HPG, HgI etc, X-ray detectors; Cryogenic detectors.
Abstract Sample 5
Hodgkinson, J., & Tatam, R. P.( 2012, November 28). Optical gas sensing: a review. Measurement Science and Technology , 24(1). Retrieved December 1, 2017 from http://iopscience.iop.org/article/10.1088/0957-0233/24/1/012004/meta
Topical Review: The detection and measurement of gas concentrations using the characteristic optical absorption of the gas species is important for both understanding and monitoring a variety of phenomena from industrial processes to environmental change. This study reviews the field, covering several individual gas detection techniques including non-dispersive infrared, spectrophotometry, tunable diode laser spectroscopy and photoacoustic spectroscopy. We present the basis for each technique, recent developments in methods and performance limitations. The technology available to support this field, in terms of key components such as light sources and gas cells, has advanced rapidly in recent years and we discuss these new developments. Finally, we present a performance comparison of different techniques, taking data reported over the preceding decade, and draw conclusions from this benchmarking.
Abstract Sample 6
Zhao, B. & Yang, J. (2013, July 10). New effects in an ultracompact Young's double nanoslit with plasmon hybridization. New Journal of Physics (New J. Phys.), 15. Retrieved December 1, 2017 from http://adsabs.harvard.edu/abs/2013NJPh...15g3024Z
Abstract
We present a theoretical study on the anomalous transmission of an asymmetric Young's double metallic nanoslit with an ultrathin interval. The slit–slit interactions show exotic optical properties, particularly strong suppression of light transmission with narrow bandwidth and red/blue shifting of transmission peaks from individual slits, in contrast to currently well-developed subwavelength optical structures. Dip transmission is also observed to gradually decay with increasing interval distance. Analysis results reveal that such a phenomenon physically lies in the hybridized cross-talking of surface modes within two slits throughout the interval film in between. Depending on the plasmon hybridization type, either symmetric or antisymmetric, the newly induced optical phase retardation between the two slits can decrease and increase, respectively. This investigation suggests a potential way of nonlinearly bonding metallic waveguides and consequently aiding in the design of new plasmonic devices.
General Scientific Summary
Introduction and background. The emerging field of nano optics addresses the ability to manipulate light at the nanoscale in a metal through the use of surface plasmons, whose astonishing optical properties can lead to enhanced light transmission. In the current research on nanoslit structures, slits are usually distanced by many optical wavelengths, making the energy transfer within each element independent. Their interactions are primarily mediated by the output–interface phase matching of fields out of individual slits. Unfortunately, it is challenging to scale down the system separation to less than half the wavelength, which holds great potential for the miniaturization of integrated devices.
Main results. In this paper, we present a nanophotonic structure built from a pair of ultrathin spaced asymmetric metal slits, in which surface modes confined within two slits are physically linked through the between interval to allow cross-talking interactions. Therefore, the energy transfer within two slits becomes coherent to create the unique set of collective excitation modes. By a numerical study of the transmission spectrum and electromagnetic field evolution of the structure, we demonstrate the occurrence of exotic light suppressions, and discuss the possible mechanisms and conditions required to observe them.
Wider implications. The presented system exploits plasmon hybridization of nano-spaced metal slits and stimulates further understanding of the intriguing physics to effectively control the light signals on integrated nanophotonic devices, for example by developing the tunable high-resolution spectral filter, by designing the directional color router and coupler, or by optimizing waveguide positions to prevent their plasmonic cross talkings.
Abstract Sample7
Schulze, C., Dudley, A., Flamm, D. et al.( 2013, July 10). Measurement of the orbital angular momentum density of light by modal decomposition. New Journal of Physics (New J. Phys.), 15. Retrieved December 1, 2017 from http://iopscience.iop.org/article/10.1088/1367-2630/15/7/073025/pdf
Abstract
We demonstrate a versatile method for the measurement of the orbital angular momentum (OAM) density of an optical field. By performing a modal decomposition with digital holograms, we reconstruct the full optical field from a small set of single-point intensity measurements, from which optical vortices, global OAM and OAM density can be derived. We validate the method on defined OAM-carrying beams yielding fidelities in the OAM density measurement of up to 99%, and subsequently apply the technique to unknown fields from optical fibers.
General Scientific Summary
Introduction and background. Light carries both linear and angular momentum mechanical properties, which can be transferred to physical particles. Where the linear momentum is related to the light beam's wavelength, the angular momentum is an integer multiple of the reduced Planck constant per photon. Only some 20 years ago, it was realized that the orbital angular momentum (OAM) component was related to the spatial distribution of the light, namely to an azimuthal phase distribution, which, in the following, has accelerated research in this area due to the ease of generation of such light fields with holographic methods.
Main results. In this paper, we provide a novel measurement tool for the determination of the total orbital angular momentum and orbital angular momentum density of an arbitrary light field. We show that by modally decomposing the beam into an appropriate basis using a digital hologram, one can infer from only a few single-point intensity measurements the modal weightings and phases of any superposition, from which the OAM properties of the beam are directly accessible.
Wider implications. Such a tool is ideally suited to classical light fields where many photons exist, and in particular to modal demultiplexing of OAM states in optical communication applications, either in free-space or in fibers, and is considered to be of great significance in the fields of novel imaging and particle manipulation studies.
Abstract Sample 8
Tahir-Kheli, J. (2013, July 9). Resistance of high-temperature cuprate superconductors. New Journal of Physics (New J. Phys.), 15. Retrieved December 1, 2017 from http://iopscience.iop.org/article/10.1088/1367-2630/15/7/073020/pd
Abstract
Cuprate superconductors have many different atoms per unit cell. A large fraction of cells (5–25%) must be modified ('doped') before the material superconducts. Thus it is not surprising that there is little consensus on the superconducting mechanism, despite almost 200 000 papers (Mann 2011 Nature 475 280). Most astonishing is that for the simplest electrical property, the resistance, 'despite sustained theoretical efforts over the past two decades, its origin and its relation to the superconducting mechanism remain a profound, unsolved mystery' (Hussey et al 2011 Phil. Trans. R. Soc. A 369 1626). Currently, model parameters used to fit normal state properties are experiment specific and vary arbitrarily from one doping to the other. Here, we provide a quantitative explanation for the temperature and doping dependence of the resistivity in one self-consistent model by showing that cuprates are intrinsically inhomogeneous with a percolating metallic region and insulating regions. Using simple counting of dopant-induced plaquettes, we show that the superconducting pairing and resistivity are due to phonons.
General Scientific Summary
Introduction and background. Resistance is the simplest electrical property, yet 27 years after the discovery of high temperature cuprate superconductors, its origin in the normal state remains unexplained. While cuprates and ordinary metals both have a high temperature resistance that is linear in temperature, cuprates are atypical in three ways: (1) the resistance is strongly doping dependent, (2) it has a linear temperature component at very low temperatures, and (3) the low and high temperature slopes are different. Fundamentally, electron scattering causes resistance in the normal state while leading to electron pairing and superconductivity at lower temperatures. Therefore, cuprate superconductivity cannot be understood without an understanding of its normal state resistance.
Main results. We propose that doping leads to atomic-scale inhomogeneity. Thus cuprates are comprised of a percolating metallic region and surrounding insulating regions. The metallic region is formed from square plaquettes made from four corner copper atoms with a dopant atom over the middle. By simple counting of the number of non-overlapping and overlapping plaquettes as a function of doping, we explain the resistivity and show that it is due to electron scattering with phonons.
Wider implications. These results shed light on phonon scattering in the normal state and suggest which phonons are responsible for the Cooper pairing of electrons responsible for superconductivity. The resistivity thus yields parameters that determine the transition temperature. We conclude that, by controlling the arrangement of dopant atoms in cuprates, we may be able to engineer superconducting materials with higher transition temperatures.
Abstract Sample 9
Adhikari, A., Bourgade,T. & Asundi, A. (2016) Residual stress measurement for injection molded components. Theoretical and Applied Mechanics Letters , 6(4), 152-156.
Abstract
Residual stress induced during manufacturing of injection molded components such as polymethyl methacrylate (PMMA) affects the mechanical and optical properties of these components. These residual stresses can be visualized and quantified by measuring their birefringence. In this paper, a low birefringence polariscope (LBP) is used to measure the whole-field residual stress distribution of these injection molded specimens. Detailed analytical and experimental study is conducted to quantify the residual stress measurement in these materials. A commercial birefringence measurement system was used to validate the results obtained to our measurement system. This study can help in material diagnosis for quality and manufacturing purpose and be useful for understanding of residual stress in imaging or other applications.
Keywords
Photoelasticity; Birefringence; Residual stress; Polymethyl methacrylate
Abstract Sample 10
Zhou, Q., Wang, W. & Pang, Y. (2015) . Temporal and spatial distribution characteristics of water resources in Guangdong Province based on a cloud model. Water Science and Engineering, 8(4), 263-272.
Abstract
With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distribution characteristics of water resources in Guangdong Province from 1956 to 2000 based on a cloud model. [topic] The spatial variation of the temporal distribution characteristics and the temporal variation of the spatial distribution characteristics were both analyzed. In addition, the relationships between the numerical characteristics of the cloud model of temporal and spatial distributions of water resources and precipitation were also studied. The results show that, using a cloud model, it is possible to intuitively describe the temporal and spatial distribution characteristics of water resources in cloud images. Water resources in Guangdong Province and their temporal and spatial distribution characteristics are differentiated by their geographic locations. Downstream and coastal areas have a larger amount of water resources with greater uniformity and stronger stability in terms of temporal distribution. Regions with more precipitation possess larger amounts of water resources, and years with more precipitation show greater nonuniformity in the spatial distribution of water resources. The correlation between the nonuniformity of the temporal distribution and local precipitation is small, and no correlation is found between the stability of the nonuniformity of the temporal and spatial distributions of water resources and precipitation. The amount of water resources in Guangdong Province shows an increasing trend from 1956 to 2000, the nonuniformity of the spatial distribution of water resources declines, and the stability of the nonuniformity of the spatial distribution of water resources is enhanced.
Keywords
Water resources; Temporal and spatial distribution characteristics; Cloud model; Guangdong Province
Abstract Sample 11
Sillmann, J., Thorarinsdottir, T. & Keenlyside , N. (2017, November 4). Understanding, modeling and predicting weather and climate extremes: Challenges and opportunities. Weather and Climate Extremes . Retrieved November 26, 2017, from https://doi.org/10.1016/j.wace.2017.10.003Get rights and content
Abstract
Weather and climate extremes are identified as major areas necessitating further progress in climate research and have thus been selected as one of the World Climate Research Programme (WCRP) Grand Challenges. Here, we provide an overview of current challenges and opportunities for scientific progress and cross-community collaboration on the topic of understanding, modeling and predicting extreme events based on an expert workshop organized as part of the implementation of the WCRP Grand Challenge on Weather and Climate Extremes. In general, the development of an extreme event depends on a favorable initial state, the presence of large-scale drivers, and positive local feedbacks, as well as stochastic processes. We, therefore, elaborate on the scientific challenges related to large-scale drivers and local-to-regional feedback processes leading to extreme events. A better understanding of the drivers and processes will improve the prediction of extremes and will support process-based evaluation of the representation of weather and climate extremes in climate model simulations. Further, we discuss how to address these challenges by focusing on short-duration (less than three days) and long-duration (weeks to months) extreme events, their underlying mechanisms and approaches for their evaluation and prediction.
Abstract Sample 12
Yang, H., Xie, S. & Secq, J.(2017). Experimental study and modeling of hydromechanical behavior of concrete fracture. Water Science and Engineering . 10(2), 97-1-6.
Abstract
In this study, the hydromechanical behavior of a concrete fracture under coupled compressive and shear stresses was investigated. A special experimental device was designed to create a planar fracture in a cylindrical sample and to carry out different kinds of hydromechanical tests on the fracture. Four series of laboratory tests were performed on an ordinary concrete sample. Hydrostatic compression tests were first conducted to characterize the normal compressibility of the fracture. In the second series, direct shear tests were conducted on the fracture under different normal stresses. The maximal shear stress of the fracture was determined as a function of the normal stress. In the third series, fluid flow tests were carried out in view of characterizing the overall hydraulic conductivity of the fracture as a function of its opening and closure. Shear tests with a constant fluid pressure were finally performed to investigate the influence of fluid pressure on the deformation behavior of concrete fractures. Based on the experimental investigation, an elastoplastic model is proposed. This model takes into account the nonlinear elastic behavior of a fracture under normal compression and the plastic deformation and failure due to shear stress. The model was coupled with the classical Darcy's law to describe the fluid flow along the fracture by considering the variation of permeability with fracture aperture. Numerical results agree with experimental data from various laboratory tests.
Keywords
Concrete fracture; Direct shear; Hydromechanical coupling; Hydraulic conductivity; Elastoplastic model
Abstract Sample 13
Yang, J. L. (2016). ) Criticism to Universal Big Bang. J Astrophys Aerospace Technol, 4(1), 129-133.
Abstract
This paper defends Dialectical materialism's world outlook, and in detail criticizes idealism's finite space-time to use modern scientific theory and observed facts from different ways and points of view, and reveals the absurdity and radical mistakes of universal big bang, the expansion and contraction of universe are proved to circulate repeatedly, the singular point of big bang didn’t exist, more reasonably explain cosmic microwave background radiation, and in the same time recommend a new steady state model of universal evolution, which corresponds with infinite space-time, give out the mechanism of formation and evolution of galaxies and celestial bodies based on the continuous generation of matter, and prove galaxies and celestial are growing up with the expansion of universe, and besides, the earth dynamics is taken in the framework of cosmology, earthquake proves the performance of the earth growing up, rather than so-called plate collision.
Keywords
Big bang theory of universe; Microwave background; Radiation; Formation of earth
Abstract Sample 14
Ghazaw, Y. M.(2011). Design and analysis of a canal section for minimum water loss. Alexandria Engineering Journal , 50(4), 337-344
Abstract
Seepage and evaporation are the most serious forms of water loss in an irrigation canal network. Seepage loss depends on the channel geometry, while evaporation loss is proportional to the area of free surface. In this paper, a methodology to determine the optimal canal dimensions for a particular discharge is developed. The nonlinear water loss function, for the canal, which comprises seepage and evaporation loss, was derived. Two constraints (minimum permissible velocity as a limit for sedimentation and maximum permissible velocity as a limit for erosion of canal) have been taken into consideration in the canal design procedure. Using Lagrange’s method of undetermined multipliers, the optimal canal dimensions were obtained for minimum water loss. A computer program was developed to carry out design calculation for the optimal canal dimensions. The results are plotted in form of a set of design charts. The proposed charts facilitate easy design of the optimal canal dimensions guaranteeing minimum water loss. Water loss from the canal section can be estimated from these charts without going through the conventional and cumbersome trial and error method. Sensitivity analysis had been included to demonstrate the impact of important parameters.
Keywords
Design charts; Canal design; Optimal dimensions; Seepage loss; Evaporation loss
Abstract Sample 15
He, L., Du, P. & Chen, Y. (2017). Advances in microbial fuel cells for wastewater treatment. Renewable and Sustainable Energy Reviews , 71, 388-403.
Abstract
Resources scarcity and electricity demand have been dramatically increasing. Wastewater is recognized as one of resources for water, energy and plant fertilizing nutrients. Nevertheless, current wastewater treatment technologies have limitations due principally to their energy- and cost-intensive for achieving the conversion target of wastewater recovery. It is desired to develop a new technology to generate alternatives to conventional energy sources in a sustainable manner. An innovative technology based on the use of microbial fuel cells (MFCs) has been proved as a critical pathway for bioconversion processes towards electricity generation, then for addressing energy and environmental problems. Three special features including energy saving, less sludge production and less energy production make MFCs outstanding compared with the existing technologies. Multiform wastewaters could be efficiently degraded through advancing MFCs alone or integrating MFCs with other processing units. However, the low power density and the high operating cost of MFCs have greatly limited their applications on large-scale problems, and then result in some debates and doubts about their development and applications. Therefore, this paper objectively discussed the problems and applications of MFCs in wastewater treatment. Moreover, the integration of MFCs with other treatment processes was presented to verify the practicality and effectiveness of MFCs in contaminants removal.[results] Furthermore, the primary challenges and opportunities for scaling-up and future applications of MFCs in wastewater were analyzed.[wider implications].
Keywords
Electricity; Wastewater treatment; Microbial fuel cell; Energy Contaminants removal
Abstract Sample 15
Moharram, K.A., Abd-Elhady, M.S. & Kandil, H.A.(2013). Enhancing the performance of photovoltaic panels by water cooling. Ain Shams Engineering Journal , 4(4), 869-877
Abstract
The objective of the research is to minimize the amount of water and electrical energy needed for cooling of the solar panels, especially in hot arid regions, e.g., desert areas in Egypt. [objective] A cooling system has been developed based on water spraying of PV panels. A mathematical model has been used to determine when to start cooling of the PV panels as the temperature of the panels reaches the maximum allowable temperature (MAT). A cooling model has been developed to determine how long it takes to cool down the PV panels to its normal operating temperature, i.e., 35 °C, based on the proposed cooling system. Both models, the heating rate model and the cooling rate model, are validated experimentally.[results] Based on the heating and cooling rate models, it is found that the PV panels yield the highest output energy if cooling of the panels starts when the temperature of the PV panels reaches a maximum allowable temperature (MAT) of 45 °C. The MAT is a compromise temperature between the output energy from the PV panels and the energy needed for cooling.[conclusions]
Keywords
Photovoltaic; Cooling; Overheating
Appendix 2
Дата: 2019-03-05, просмотров: 227.