인공고관절의 세라믹 볼 헤드의 기계적 안정성 평가를 위한 3 차원 유한요소 해석

第12次 아시아ㆍ太平洋 矯政局長會議 參加記

13. 벼잎선충의 약제처리 방법별 방제 효과

Optical Waveguide Theory

PREFACE The advantages which have been derived from the caution with which hypothetical statements are admitted, are in no instance more obvious than in those sciences which more particularly belong to the healing art. It therefore is necessary, that some conciliatory explanation should be offered for the present publication: in which, it is acknowledged, that mere conjecture takes the place of experiment; and, that analogy is the substitute for anatomical examination, the only sure foundation for pathological knowledge. When, however, the nature of the subject, and the circumstances under which it has been here taken up, are considered, it is hoped that the offering of the following pages to the attention of the medical public, will not be severely censured. The disease, respecting which the present inquiry is made, is of a nature highly afflictive. Notwithstanding which, it has not yet obtained a place in the classification of nosologists; some have regarded its characteristic symptoms as distinct and different diseases, and others have given its name to diseases differing essentially from it; whilst the unhappy sufferer has considered it as an evil, from the domination of which he had no prospect of escape. The disease is of long duration: to connect, therefore, the symptoms which occur in its later stages with those which mark its commencement, requires a continuance of observation of the same case, or at least a correct history of its symptoms, even for several years. Of both these advantages the writer has had the opportunities of availing himself, and has hence been led particularly to observe several other cases in which the disease existed in different stages of its progress. By these repeated observations, he hoped that he had been led to a probable conjecture as to the nature of the malady, and that analogy had suggested such means as might be productive of relief, and perhaps even of cure, if employed before the disease had been too long established. He therefore considered it to be a duty to submit his opinions to the examination of others, even in their present state of immaturity and imperfection. To delay their publication did not, indeed, appear to be warrantable. The disease had escaped particular notice; and the task of ascertaining its nature and cause by anatomical investigation, did not seem likely to be taken up by those who, from their abilities and opportunities, were most likely to accomplish it. That these friends to humanity and medical science, who have already unveiled to us many of the morbid processes by which health and life is abridged, might be excited to extend their researches to this malady, was much desired; and it was hoped, that this might be procured by the publication of these remarks. Should the necessary information be thus obtained, the writer will repine at no censurewhich the precipitate publication of mere conjectural suggestions may incur: but shall think himself fully rewarded by having excited the attention of those, who may point out the most appropriate means of relieving a tedious and most distressing malady.

An Essay on the Shaking Palsy

We describe a reproducible method of fabricating adiabatic tapers with 3–4μm diameter. The method is based on a heat-and-pull rig, whereby a CO2 laser is continuously scanned across a length of fiber that is being pulled synchronously. Our system relies on a CO2 mirror mounted on a geared stepper motor in order to scan the laser beam across the taper region. We show that this system offers a reliable alternative to more traditional rigs incorporating galvanometer scanners. We have routinely obtained transmission losses between 0.1 and 0.3dB indicating the satisfactory production of adiabatic tapers. The operation of the rig is described in detail and an analysis on the produced tapers is provided. The flexibility of the rig is demonstrated by fabricating prolate dielectric microresonators using a microtapering technique. Such a rig is of interest to a range of fields that require tapered fiber fabrication such as microcavity-taper coupling, atom guiding along a tapered fiber, optical fiber sensing, and the fabrication of fused biconical tapered couplers.

Heat-and-pull rig for fiber taper fabrication

Subwavelength features in conjunction with light-guiding structures have gained significant interest in recent decades due to their wide range of applications to particle and atom trapping. Lately, the focus of particle trapping has shifted from the microscale to the nanoscale. This few orders of magnitude change is driven, in part, by the needs of life scientists who wish to better manipulate smaller biological samples. Devices with subwavelength features are excellent platforms for shaping local electric fields for this purpose. A major factor that inhibits the manipulation of submicrometer particles is the diffraction-limited spot size of free-space laser beams. As a result, technologies that can circumvent this limit are highly desirable. This review covers some of the more significant advances in the field, from the earliest attempts at trapping using focused Gaussian beams, to more sophisticated hybrid plasmonic/metamaterial structures. In particular, examples of emerging optical trapping configurations are presented.

Optical trapping and manipulation of micrometer and submicrometer particles

A single-input whispering gallery optical microbubble resonator is presented. Spherical microbubbles with diameters less than 100 μm, micrometer-sized wall thicknesses, and a single opening or input were fabricated by heating the tapered tip of a pressurized glass capillary using a CO2 laser. Optical whispering gallery modes with Q factors of ∼105 were obtained. The bubbles were filled with water and mode shifts of ∼20 GHz were observed. Fano-type resonances were detected when the coupling optical fiber diameter was less than 1μm, causing the microresonator to switch from being a band-stop filter to a bandpass filter. Larger bubbles with submicrometer wall thickness were also fabricated.

Single input Spherical Microbubble Resonator

The ability of metallic nanostructures to confine light at the sub-wavelength scale enables new perspectives and opportunities in the field of nanotechnology. Making use of this unique advantage, nano-optical trapping techniques have been developed to tackle new challenges in a wide range of areas from biology to quantum optics. In this work, starting from basic theories, we present a review of research progress in near-field optical manipulation techniques based on metallic nanostructures, with an emphasis on some of the most promising advances in molecular technology, such as the precise control of single-biomolecules. We also provide an overview of possible future research directions of nano-manipulation techniques.

/pdf/plasmonic-optical-tweezers-based-on-nanostructures-2qj26g80jj.pdf

Síle Nic Chormaic

Papers

Heat-and-pull rig for fiber taper fabrication

Optical trapping and manipulation of micrometer and submicrometer particles

Single input Spherical Microbubble Resonator

Plasmonic optical tweezers based on nanostructures: fundamentals, advances and prospects

Higher order mode propagation in an optical nanofiber