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This article proposes a new refined definition of light, which makes it possible to harmonize the wave and corpuscular concepts of this object of matter and quantitative relations that describe the wave-corpuscular nature of the phenomena of interference, diffraction, dispersion, polarization, external and internal photoeffects as phenomena as well as such electroluminescence and photoluminescence associated with light.

In this paper, we study the transmission properties of light through the Family A of Generalized Thue–Morse [FAGTM(n)] aperiodic multilayers and find that for the normal incidence of light there exist three kinds of cases for propagation matrices and corresponding transmission coefficients: (1) when n is even, the former are two-circular and the latter are constant; (2) when n = 1, the former and the latter are all constant; (3) when n is odd but does not equal to 1, the former are all diagonal except the 1st-generation system. The two nonzero elements are countdowns for each other and decrease or improve rapidly with the increase of both the generation number l and the parameter n. The latter are constant when l≤2 and tend to be zero when l≥3. The analytic results are confirmed by numerical simulations.

Electromagnetic measurement technology is an important method for instrument parameters calibration, detection performance evaluation and complex system theory verification. In this paper, self-adaptive finite element method has been used to compute and analyze the weak electromagnetic wave signal, which is produced by changing electrode structure, transmitting frequency and antenna spacing of the through casing electromagnetic measurement tool. Numerical simulation results show that the detection depth of the tool can be influenced by the electrode structure can have the influence on, the resolution of high-resistivity and low-resistivity formation can be improved by transmitting frequency, the detection accuracy and detection depth of the through casing electromagnetic measurement tool can be influenced by the change of antenna spacing.

China accounts for more than 22% of the total energy consumption worldwide. Building energy consumption, among which consumption in public buildings was about 40% took the second place. With the problems of high energy waste, error rate and complexity of the control systems available, an indoor intelligent lighting system based on occupants’ location is proposed in this paper to improve the energy efficiency of the current lighting systems indoors. The transmission model of electromagnetic wave in free space is optimized in both aspects of reference signal strength and attenuation coefficient radiation in complex environment dynamically based on which occupants’ positions are obtained. The smart lighting system will turn on or off corresponding lights adaptively to provide a more energy efficient platform. Experimental results show that the proposed system is able to improve the energy efficiency of indoor lighting by at least 15%, with a lower error rate below 2% compared with the existing lighting systems based on voice control.

Bondi–Sachs (BS) framework is a powerful tool to analyze the asymptotical null structure of a spacetime. Based on Bondi’s outgoing boundary condition, the asymptotical null structure of an electro-vacuum spacetime without a cosmological constant has been constructed clearly. Recently more and more observations imply that the Einstein equation should be modified with an nonzero cosmological constant. It is interesting to investigate the asymptotical null structure of a spacetime with a cosmological constant. In this paper, we extend our previous result from vacuum case to electro-vacuum case. We find that the gravitational sector of the asymptotical null structure depends strongly on the boundary conditions, while the electrical sector is independent of the boundary condition.

Australia Helps Map Transcriptome of Mouse Genome.

Blood Cell Protein Mutation Slows Malaria.

Chinese Scientists Complete Detailed Rice Genome Map.

Three New Human Genes Discovered Among Chinese.

Abnormal Chromosomes Related to Habitual Abortion Found.

Rice Genome Sequencing by Japan-led Team Completed.

Study Shows Rats not Affected by Electromagnetic Wave.

Researchers Clone Monkey Embryos.

Folic Acid Reduces Heart Disease Risk.

NZ in International Brain Hemorrhage Study.

NTU and Sun Microsystems Collaborate on High Performance Computing for Life Sciences.

National Cheng Kung University Named as Bioinformatics Center of Excellence.

Carpal Tunnel Effectively Treated with Short-term Steroids.

Taiwan Scientists Clone Liver Cells.

Wide-band absorption with low density is essential for microwave absorbers. We fabricated a novel micro-fibrous Fe/C nanocomposite with bulk density of only 0.47 ± 0.03 g cm^-3 using carbonized cotton fibers as template. Monodisperse iron nanoparticles with diameter of about 100 nm covered on the fibers and significantly increased the complex permittivity and permeability, and therefore enhanced the reflection loss (RL) for electromagnetic waves. The optimum thickness for the nanocomposite is 1.5–1.8 mm, with maximum RL of -14 dB and bandwidth of RL < -5 dB from 10 to 18 GHz, similar to that of Fe/C nanocomposite without using carbonized cotton fibers. Because of its low density and broad bandwidth at thin matching thickness, micro-fibrous Fe/C nanocomposite is a promising light-weight microwave absorber.

With the gas ionization experiments (Section 1.7) we know that atoms and molecules are made of nuclei and electrons that revolve around them. In this chapter we give representations of these microscopic objects and show how certain atoms or molecular fragments form bonds between them. From the description of the hydrogen atom, the lightest atom in Nature since it contains only one proton and one electron, we will develop a simple model for the bonds between atoms in molecules stable at 25°C. Without making complicated calculations we will be able to predict which bonds between atoms are possible a priori and which structures the molecules containing them have. Atoms are the parts of a Lego® set that can be assembled to make a large number of constructions, but not just any construction (three-dimensional objects with predefined geometries). In Chapter 7, we will develop a slightly more advanced model of the chemical bond. We will examine why some bonds are weaker than others, i.e. which bonds are more or less easily broken by heating…

A fourth-order in time and space, finite-difference time-domain (FDTD) algorithm is applied to study the electromagnetic propagation in homogeneous, collision and warm plasma. The approach can significantly minimize the dispersion errors while still maintaining minimal memory requirement. For the problem of three-dimensional propagation, the scheme requires only three additional memory cells per Yee cell over and above that of the generic FDTD scheme. To investigate the validation of the fourth-order FDTD algorithm, the reflection coefficient of a slab of non-magnetized collision plasma is calculated. Comparisons between the accurate data and the results of second-order or fourth-order FDTD methods are discussed.

A fourth-order in time and space, finite-difference time-domain (FDTD) algorithm is applied to study the electromagnetic propagation in homogeneous, collision and warm plasma. The approach can significantly minimize the dispersion errors while still maintaining minimal memory requirement. For the problem of three-dimensional propagation, the scheme requires only three additional memory cells per Yee cell over and above that of the generic FDTD scheme. To investigate the validation of the fourth-order FDTD algorithm, the reflection coefficient of a slab of non-magnetized collision plasma is calculated. Comparisons between the accurate data and the results of second-order or fourth-order FDTD methods are discussed.