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Very Small Size (very + small_size)
Selected AbstractsVery small size printed monopole with embedded chip inductor for 2.4/5.2/5.8 GHz WLAN laptop computer antennaMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2010Ting-Wei Kang Abstract A very small size planar two-strip monopole printed on a thin (0.4 mm) FR4 substrate for 2.4/5.2/5.8 GHz triple-band WLAN operation in the laptop computer is presented. With the aid of an embedded chip inductor of 5.6 nH in the longer strip of the printed monopole, a much reduced strip length for obtaining the resonant mode at about 2.4 GHz is obtained, thereby leading to a much reduced size of the antenna for the desired WLAN operation. When the antenna is mounted along the top edge of the display ground, it shows a height of 9 mm and a length of 6 mm only, which is about the smallest among the triple-band WLAN laptop computer antennas that have been reported. Details of the proposed antenna are described. Results of the fabricated prototype, including the user's hand effects on the antenna performances, are presented. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 171,177, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24843 [source] High abundance of larval rockfish over Cobb Seamount, an isolated seamount in the Northeast PacificFISHERIES OCEANOGRAPHY, Issue 3 2001John F. Dower The larval fish community in the region of Cobb Seamount (500 km west of Oregon) is dominated by myctophid species commonly encountered in the subarctic North Pacific. However, during a survey in June 1992, the ichthyoplankton community within 30 km of the seamount summit was almost completely dominated by larvae of various rockfish (Sebastes) species. Given their very small size (and hence very young age) and the fact that they occurred only rarely in samples collected > 30 km from the seamount summit, we conclude that these Sebastes larvae were produced locally over Cobb Seamount. Previous studies have shown that the Cobb fish fauna is dominated by various Sebastes spp. and that, unlike other fish present on the seamount, the rockfish populations may be self-recruiting. We suggest that a persistent clockwise (i.e. downwelling) eddy, consistent with a stratified Taylor cone, plays a critical role in retaining larval rockfish over Cobb Seamount and may contribute to the process of self-recruitment. The key to the success of rockfish on Cobb and other shallow Northeast Pacific seamounts seems to be linked to their viviparous life history. [source] A two-grid fictitious domain method for direct simulation of flows involving non-interacting particles of a very small sizeINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 11 2010A. Dechaume Abstract The full resolution of flows involving particles whose scale is hundreds or thousands of times smaller than the size of the flow domain is a challenging problem. A naive approach would require a tremendous number of degrees of freedom in order to bridge the gap between the two spatial scales involved. The approach used in the present study employs two grids whose grid size fits the two different scales involved, one of them (the micro-scale grid) being embedded into the other (the macro-scale grid). Then resolving first the larger scale on the macro-scale grid, we transfer the so obtained data to the boundary of the micro-scale grid and solve the smaller size problem. Since the particle is moving throughout the macro-scale domain, the micro-scale grid is fixed at the centroid of the moving particle and therefore moves with it. In this study we combine such an approach with a fictitious domain formulation of the problem resulting in a very efficient algorithm that is also easy to implement in an existing CFD code. We validate the method against existing experimental data for a sedimenting sphere, as well as analytical results for motion of an inertia-less ellipsoid in a shear flow. Finally, we apply the method to the flow of a high aspect ratio ellipsoid in a model of a human lung airway bifurcation. Copyright © 2009 John Wiley & Sons, Ltd. [source] Extra small virus-like particles (XSV) and nodavirus associated with whitish muscle disease in the giant freshwater prawn, Macrobrachium rosenbergiiJOURNAL OF FISH DISEASES, Issue 9 2003D Qian Abstract A disease of Macrobrachium rosenbergii, the giant freshwater prawn, farmed in China was recently recorded in Zhejiang, Jiangsu, Shanghai, Guangxi and Guangdong provinces. The clinical sign of the disease, which develops in post-larvae (PL), is a whitish appearance of the muscles, particularly noticeable in the abdomen. Mortalities may reach 100% in some hatcheries. Investigations by transmission electron microscopy after negative staining of diseased PL homogenates showed the presence of two types of viral particles: one, unenveloped, icosahedral in shape, 26,27 nm in diameter, the second, much smaller, about 14,16 nm in diameter, designated extra small virus particle (XSV). The large virus has a genome with two pieces of ssRNA (RNA-1 and RNA-2), of 3 and 1.2 kb, respectively. Hybridization tests confirmed that this large virus is closely related to M. rosenbergii nodavirus (MrNV) which was isolated from diseased prawns in a hatchery in the French West Indies. Its very small size and hypothesized biochemical and biological characteristics suggest XSV is a new type of crustacean virus. As XSV has always been found associated with the larger virus (nodavirus) and is located in muscle and connective cells of diseased animals, it could be an autonomous virus, a helper-type virus or a satellite-like virus. [source] The ,frameless' intrauterine system for long-term, reversible contraception: A review of 15 years of clinical experienceJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 3 2003Dirk Wildemeersch Abstract Aim:, The development of the ,frameless' intrauterine system (IUS) is a response to the growing need to develop high-performing, long-acting, reversible, and acceptable contraceptives with a high continuation of use. Methods:, This is a review of 15 years of clinical experience in randomized controlled and non-randomized clinical trials. Results:, The IUS has a similar failure rate as the TCu380A Intrauterine device (IUD), considered the ,golden standard' IUD, which is attributed to the optimal target delivery of the copper ions in the upper part of the uterine cavity. Its performance is further optimized by the atraumatic design, which reduces partial and total expulsion and minimizes the side-effects and discomforts experienced with conventional ,framed' IUDs. The mini IUS is likely to further reduce the menstrual blood loss due to the very small size. The safety of the anchoring concept is beyond doubt as was demonstrated in all clinical studies covering 15 000 woman-years experience. Conclusions:, Young nulliparous/nulligravid and parous women may significantly benefit from the advantages the ,frameless' IUS, which could be strategically important to help in reducing the increasing number of unintended pregnancies and induced abortions worldwide. Furthermore, the ,frameless' IUS has been shown to be highly effective for emergency contraception and for immediate postabortal insertion. The long lifespan of the IUS could constitute a cost-effective reversible alternative to irreversible female sterilization. [source] Efficient electrically small loop antenna using SRR structure on the ground planeMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009Joong-Kwan Kim Abstract In this article, an electrically small loop antenna using capacitive loading is proposed. The loop antenna acts as an inductive element and the gap between two lines of SRR in the ground plane acts as a capacitive element; hence the combined system with these two elements is operated as a LC resonator. The equivalent circuit model of the antenna structure is applied to analyze and qualify the design correctness. Although the proposed antenna has a very small size, it shows a good performance. The measured maximum gain and radiation efficiency of the fabricated antenna at the frequency of 2.04 GHz are 3.6 dBi and 81.02%, respectively. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 201,204, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24016 [source] | |||||||||||||