2,968 research outputs found

    FURTHER INVESTIGATION ON MAGNETICALLY INDUCED SUBSEQUENT FAULT AND STUDY ON ELECTROMAGNETIC SCATTERING OF OBJECTS BURIED BELOW A RANDOM ROUGH SURFACE

    Get PDF
    This dissertation contains two subjects: further development of numerical technique for the analysis of magnetically induced subsequent fault (MISFault) in overhead power lines and its implementation into a software upgrade; and first-phase of study on the electromagnetic scattering from objects buried below a random rough surface making use of the multidomain pseudospectral time domain (PSTD) method and Monte-Carlo simulation. An initial electric fault can result in strong magnetic torque on the overhead power line conductors, which will make them swing and may bring them to close proximity or in contact with one another, causing a subsequent fault. In Chapter 2, Computer simulations for the analysis of the subsequent fault in transition spans, which are often required in power line topology, are developed. A dynamic analysis of swing movement of power line conductors subsequent to an initial fault is presented to track the smallest distance between the conductors. In Chapter 3, the simulation is implemented into the upgrade of the MISFault analysis software. Its functions are depicted in details. The MISFault software is being used by Duke Energy Company and is expected to be useful to a utility for eliminating the magnetically induced subsequent faults. The multidomain pseudospectral time domain (PSTD) method has been developed and successfully applied to solve a variety of electromagnetic scattering problems in the past decade. It is a novel algorithm with improvement over traditional FDTD method. In Chapter 4, a multidomain PSTD algorithm is developed to investigate the scattering from a 2-D cylinder in free space. Sample numerical results are presented and validated. Then, the theoretical derivations are extended for the analysis of scattering from 2-D objects buried below a random rough surface

    Bis{1-[(1H-benzotriazol-1-yl)meth­yl]-2-methyl-1H-imdazole-κN 3}dichlorido­zinc

    Get PDF
    In the mononuclear title compound, [ZnCl2(C11H11N5)2], the ZnII atom is coordinated by two Cl atoms and two imidazole N atoms in a distorted tetra­hedral geometry. Adjacent complex mol­ecules are stacked through aromatic π–π inter­actions; the closest distance between adjacent aromatic rings is 3.598 (2) Å

    The Main Body and Legal Basis of American Graduate Degree Awarding Authority

    Get PDF
    The right to confer postgraduate degrees is involved a key measure to universities and its students. Nations in the world pay a very high attention to postgraduate education and play it core role. As we known, U.S. has rich resources and great influences in the field of higher education worldwide. And there are many students from all over the world to enroll American universities to study for master or doctor degree. Although the degree is divided into curriculum and paper degree, the quality of both are strictly regulated and guaranteed in the United States. The main body has become different types of universities and diversity pattern in the course of developing. The right to award degree was struggled by universities in the development of history, and it is a part of its charter. In the process, the legitimacy of awarding degree gradually was established. As so far, it is known as an important measure for the development of universities and students. There are different bodies of the right to grant graduate degrees in American universities, and the methods of obtaining graduate degrees are also different. How to ensure that the right to confer university degrees is not affected by the government and its actions? This paper will explicit from the point view of legal basis

    Humanism in Medicine

    Get PDF
    Immobilizing antimicrobial substances onto biocompatible materials is an important approach for the design of novel, functionalized medical devices. By choosing antimicrobial substances from innate immune systems, the risk for development of resistance in pathogenic microbes is lower than if conventional antibiotics are used. Combining natural antimicrobial peptides and bactericidal enzymes with strong and elastic spider silk through recombinant protein technology would enable large-scale production of materials that could serve as functionalized wound dressings. Herein, fusion proteins with the engineered spider silk sequence 4RepCT and five different antimicrobial substances were constructed using two different strategies. In the first, the fusion proteins had a His-tag as well as a solubility-enhancing domain N-terminally to the antimicrobial agent during expression. The tags were cleaved and separated from the target protein during the purification process. The other approach provided a His-tag but no additional solubility domain. The antimicrobial agents included in the work were a charge engineered enzyme and four antimicrobial peptides herein called Peptide A, Peptide B, Peptide C and Peptide D. Four out of five fusion proteins could be expressed in Escherichia coli without exhibiting noticeable toxicity to the host. However, most target proteins were found in the non-soluble fraction. For D-4RepCT, neither soluble nor non-soluble proteins were identified. An operating strategy for expression and purification of antimicrobial spider silk proteins was developed, where the construct system providing the solubility-enhancing domain N-terminally to the antimicrobial sequence, and long time expression at low temperatures is a promising approach. The fusion proteins A-4RepCT and C-4RepCT could be produced in adequate amounts, and they proved to possess the ability to assemble into stable fibers. When incubating solutions of Escherichia coli on the functionalized silk material A-4RepCT, it showed to decrease the number of living bacteria in solution, in contrary to wild-type 4RepCT on which bacteria continued to proliferate. Initial studies of the viability of bacteria adhered to the surface of the functionalized spider silk are so far inconclusive. A larger sample size, complementary experiments and methodology optimization is needed for a proper assessment of antibacterial properties. However, preliminary results for the development of antimicrobial spider silk are positive, and the approach elaborated in this work is believed to be applicable for the construction of functional spider silk with a wide range of natural antimicrobial agents for future wound healing applications
    corecore