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The problem is effect of electromagnetic wave. When electromagnetic wave obliquely transmitted through two different medias ,electromagnetic wave undergoes reflection and refraction at the interface and inside the media. Computation of electromagnetic wave is well known by Maxwell`s equation. There are two cases solving questions. One is constant of £g¡B£`¡B£m.Another is variable of £g¡B£`¡B£m. In case one, use D`Alembertian equation and Helmholtz equation transforming Maxwell`s equation. And solve by ILHI`s(incomplete Lips-chitz-Hankel integrals) and FFT(fast Fourier transform). In case two,if £g¡B£`¡B£m are variables ,we can simplify Maxwell`s equation. It is similar to wave equation with source. We use Finite Element Method(FEM) getting Numerical solution by setting absorbing boundary and mesh. Using results by ILHI`s would get exact solution obliquely incident on two medias. Proof numerical solution by exact solution.

京都大学 / 0048 / 新制・論文博士 / 博士(工学) / 乙第12984号 / 論工博第4131号 / 新制||工||1637(附属図書館) / 32454 / 京都大学大学院工学研究科電子物性工学専攻 / (主査)教授 北野 正雄, 教授 竹内 繁樹, 准教授 久門 尚史 / 学位規則第4条第2項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Approved for public release; distribution is unlimited / Variability of the MABL and its effect on the electromagnetic (EM) refractive structure around the Greenland Sea marginal ice zone were examined. Rawinsonde profiles and surface observations collected from 3 ships during MIZEX-87(20 March-11 April) served as the data set. A program, developed to calculate the refractivity at each vertical level of the rawinsonde profiles, also identified the levels at which trapping, superrefraction and subrefraction occurred. Temporal studies showed that a higher incidence of anomalous refractive layers occurred during periods when the region was under the influence of high pressure. More than 50% of the time, trapping and super-refractive layers were attributed to development of a capping inversion just above the MABL during these periods. Spatial studies showed that the refractive structure varied relative to distance from the ice edge as did the depth of the MABL. An upward slope in refractive layer heights was observed from the ice toward the open water. Significant spatial inhomogeneity was observed over horizontal ranges of less than 100 km. This was attributed to both the large-scale synoptic forcing affecting the region and to variations in the surface fluxes of heat and moisture over the ice and over the water. A range-dependent ray trace model developed at the Naval Ocean Systems Center was used to show how the ray paths of EM waves vary with a changing refractive structures. Keywords: Air water interactions, Greenland Sea, Atmospheric refraction, Electromagnetic wave propagation, Heat flux, Sea ice. Theses. (EDC) / http://archive.org/details/temporalspatialv00grot / Lieutenant, United States Navy

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In the early 90s¡¦, the government of the Republic of China, Taiwan (ROC) declared the end of martial law. Taiwanese society has moved toward multi-dimensional development, which includes the greater liberal awareness of the public, as well as gradually forming various but unique social cultures. Among these cultural changes is the right to public dispute. In the past two decades, several public disputes have occurred; from the dispute against environmental pollution by the petrochemical industry, including the Chinese Petroleum Corporation, followed by the establishment of a Du Pont chemical factory, the rejection of garbage disposal plant & incinerator building, the anti-construction of nuclear power plants & the Mei Nong reservoir. To attract more customers and to pre¡Vdominate the potential market, competitors in the telecommunication industry have implemented strategies to build excess mobile base station to enhance the quality of the signal reception. From recent scientific research, there is no clear evidence to prove that electromagnetic wave signals from mobile telecommunications have any direct impact on human health. In the Year 2000, the Executive Environmental Department in Taiwan has officially announced that electromagnetic wave signals from mobile telecommunications were not a source of pollutants. However, the objection of anti-establishing mobile base station has gradually become one of the leading issues of public dispute. The dispute approaches have tended to be radical and irrational, which has lead to strong violence. In the mean time, the government and the telecommunication industry are not able to respond to and resolve the current situation. These issues not only threaten the ability for the mobile telecommunication industry to survive, but cost an incredible amount of the social resource which it is also a great concern for the similar conditions in future society. The research motivations were developed by considering the special cultural backgrounds mentioned above. The literature review includes the following research areas: conflict management; the crises interventional communication; negotiating skills; legislation process study; and the theory of outsourcing study. Furthermore, surveys on professional groups were completed to seek expertise and feedback to help resolve public radical situations. Interviews were also conducted on some key radical and irrational people to increase the public awareness about the severity of disputes. In this study, the author also investigates reasons behind public disputes and what the public has experienced and learned. To summarize, the findings of this study: 1. In the current stage, the managerial approach only resolves a radical situation as it happens; a long term and systematic methodology is still unavailable and yet to be developed. Even though the short term resolution allows authorities to accumulate precious experiences in managing public pressure, the current methodology can not effectively prevent and avoid public disputes occurrence. 2. The fundamental idea from authorities is still in favor of ¡§technical educations¡¨ which permits technicians to take major responsibilities in implementing the idea of ¡§technical skill demonstrations¡¨ to communicate and lead the agenda. However, the outcomes do not appear to be effective to those irrational and radical disputes. 3. Political power interventions mean the government is unable to provide a stable environment for industrial developments. There are politicians¡¦ interventions from different parties; public threatens and violence might also be the reasons that cause immobilized feedbacks from the government. Based on the investigation on the pros and cons of disputes on excess mobile base station and possible dispute modes, long term and short term solutions were developed. The solutions include: 1. Possible long term solutions: (1) Develop long term strategic plans, which enable the prevention of future dispute. The practical plans include media operations, professional propaganda planning, management for united industrial unions on public disputes and offers of technical and general product propagandas to the public. (2) Organizational structure justifications, traditional conceptual changes in public disputes and formations of special negotiation teams: the authority should initiate with its negotiation process based on public opinions rather than listed contents with technical issues. Professional teams should have the ability to implement the law, the public relationship and technology to the public. (3) A liberal and a specific budget support for individual projects. (4) Mobile base station embellishments and joint venture with the industrial union. (5) Provide outsourcing to professionalism. (6) Seeking for political assistances: Through democratic operations, the government should maximize its ability in public authority monitoring and the law execution. This also ensures and protects legal welfares for the mobile telecommunication industry. 2. Possible short term solutions: (1) General strategies in station selection issues. (2) New tactics formations. (3) Training professional negotiators. (4) Holding regular conferences, exchanging ideas which draw upon useful opinions, and editing ¡§Irrational mobile base station dispute management¡¨ reference handbook. (5) Educate the public to understand and obey the law. Using the law to protect and maintain basic rights for the mobile telecommunication industry. The final discussions conclude with some proposed solutions to manage public disputes. The future research recommendations to the mobile telecommunication industry, the professional team, and the governmental organizations are also included. The aim is to establish a rational and peaceful future society and provide a stable business environment for the mobile telecommunication industry.

Calculation of electromagnetic wave propagation over irregular terrain is an important problem in many applications such as coverage calculations for radars or communication links. Many different approaches to this problem may be found in the literature. One of the most commonly used methods to solve electromagnetic boundary value problems is the Method of Moments (MoM). However, especially at high frequencies, the very large number of unknows required in the MoM formulation, limits the applicability of this method, since the memory requirement and the operation count increases by O(N2) and O(N3), respectively, where N is the number of the unknowns. Several approaches have been proposed in the literature to reduce the memory requirement and the operation count of the MoM. These approaches rely on the special structure of the impedance matrix generated by the MoM. The Conjugate Gradient (CG) method is a non stationary iterative technique that can be used to solve general asymmetric/non-Hermitian systems with an operational cost of O(N2) per iteration. Furthermore, the computational time can be improved by the Fast Fourier Transform (FFT) algorithm to perform the matrix vector multiplication that appear in any iterative technique. This approach has been successfully used in the literature to solve scattering from electrically large objects and it has been shown that the computational cost and memory requirement can be reduced to O(KNlogN) with K being the number of iterations. In this thesis, CG method accelerated with Fast Fourier Transform (CG FFT) method is applied to the problem of electromagnetic propagation over irregular terrain. Applications for electrically large rough terrain profiles are presented. The accuracy of the method is compared to the direct solution of the MoM, CG method and Free Space model with recoveries by Hata model or multiple knife-edge diffraction and reflection. The solution works on quasi-planar surfaces and profiles with small deviation like little breezy sea surface properly.

This master thesis is focused on description and research of electromagnetic waves in plasma state. Some simple cases of no-loss mode distribution of electromagnetic waves in plasma are known, for example around the coaxial cable. In other words, the properties of superconducting state in materials are shown. This view of plasma properties can significantly help to clarify observed phenomena in experimental plasma research or to outline new trends in plasma usage in this mode. The introduction and the theoretical parts describe the known theory related to the propagation of electromagnetic waves in a non-homogeneous or anisotropic environment, in the next parts of the thesis the mathematical model of the solved problem of wave propagation in plasma is mentioned and the design and realization of the experiment is followed. The model includes processing of Maxwell's reduced equations in Haeviside notation for the state of matter referred to as plasma, the design of a model for numerical modeling and analysis, and the design of a simple experiment to verify numerically analyzed results.

La transformation d'espace (TE) a été développée par J. B. Pendry et U. Leonhardt en 2006 et suscite un énorme intérêt depuis la démonstration expérimentale de la première cape d'invisibilité en micro-ondes. Cette technique permet de contrôler la propagation des ondes en modifiant les propriétés électromagnétiques de l'espace. Malgré quelques limitations liées à la bande passante ou aux pertes consécutives à l'utilisation de métamatériaux pour les dispositifs TE, cette technique a attiré l'attention de nombreux domaines (optique, microondes, acoustique, etc). L'objectif de cette thèse est de développer des applications de la TE dans le domaine antennaire à l'aide de matériaux conventionnels lorsque cela est possible et aussi d'ouvrir de nouvelles voies dans le contrôle du rayonnement des antennes. Trois applications ont été étudiées: le réflecteur « parabolique plat »; un superstrat tout diélectrique pour contrôler l'ouverture angulaire d'une antenne patch; et finalement un superstrat permettant de modifier drastiquement le rayonnement d'une antenne. Ce travail a été financé par les agences de défense du Royaume Uni et de la France (DSTL et DGA respectivement), dans le cadre du projet MIMiCRA (Metamaterial Inspired Microwave Conformai Radar Antennas). / Transformation Electromagnetics technique was introduced by J. B. Pendry and U. Leonahrdt in 2006 and it has become an emerging research field in physics and engineering in the last few years after the concept was validated experimentally with a invisibility cloak in microwave regime. This technique claims the possibility of an unprecedented technique to control electromagnetic waves interaction with engineered materials to achieve exotic electromagnetic behaviour. Despite some issues about narrow bandwidth or excessive dispersive losses related to the use of metamaterials for realization of TE devices, this technique caught the attention in many research fields (optics microwave, acoustics, etc). The final purpose of this these is to explore and propose applications of Transformation Electromagnetics in the antenna design field by using standard materials with the purpose of controlling the radiation pattern of an antenna. More precisely, three applications were explored : a fiat "parabolic reflector", an all-dielectric superstrate to control the half power beamwidth of a patch antenna and finally a superstrate that allows to control drastically the radiation pattern of a planar antenna This work was funded by France and UK defence agencies (DSTL and DGA respectively), within the framework of MIMiCRA project (Metamateriallnspired Microwave Conformai Radar Antennas).

La détermination des propriétés des matériaux soumis à des chocs est un enjeu essentiel dans de nombreux domaines industriels. L’objectif de cette thèse est de proposer une nouvelle méthode fondée sur l’interrogation en bande millimétrique d’un solide soumis à un choc. Deux paramètres doivent être mesurés simultanément, la vitesse du choc et la vitesse matérielle associée afin de pouvoir construire la polaire de choc du matériau d’étude. Dans un premier temps, un état de l’art des techniques de mesure existantes est réalisé pour cibler les performances et limites de l’existant. Dans un second temps, on s’intéresse à la modélisation de la propagation des ondes électromagnétiques dans des milieux à plusieurs interfaces en mouvement et avec un gradient d’indice pour représenter des cas de choc soutenu et non soutenu. Enfin, des campagnes expérimentales d’impact plan sont présentées sur différents matériaux, inertes et explosifs, pour confronter la théorie développée aux résultats de mesure. Pour le cas des chocs soutenus, les résultats sont en très bon accord et permettent de valider le modèle. Le cas des chocs non soutenus est plus complexe. Une approche par réseau de neurones est envisagée pour permettre de remonter aux vitesses et aux indices de réfraction. Enfin, des mesures de la permittivité complexe de nombreux explosifs sont présentées. / The mechanical properties of solids under shock wave loading are a key factor in many industrial applications. This work aims at defining a new approach for the simultaneous measurement of shock wave and particle velocity during a shock event, using millimeter wave interrogation. With the two determined parameters, the shock polar of any material can be derived. First, a review of the classical methods to determine these quantities is presented, to identify the advantages and limits of such techniques. A modelization work is then performed to understand the propagation of electromagnetic waves in a stratified mediumwith moving interfaces and different refractive index in each of the layers. Such a configuration can be used to describe both steady and unsteady shocks on solids. Last, experimental results of plane impact tests on both inert and reactive materials are presented and analyzed to comfort the modelization. For steady shocks, the results are in very good agreement and prove the developed model to be adequate. The case of unsteady shocks is more complex, and a neural network approach is described to solve the problem. Finally, new data on the permittivity of high explosives and a new setup are described.