151,386 research outputs found
Enhanced lee in-building model
No full textThis paper provides a complete solution for building related propagation, starting by validating the Lee In-building model [1-3] for the single floor scenario. Then how the enhanced Lee In-building model performs in inter-floor and interbuilding cases are discussed. Measurement data were collected from 2.4G WLAN developed systems installed in many different floors in two different buildings which are connected with a corridor. The data are from multiple single floor measurements, inter floor measurement and inter building measurements. The FDTD and Ray Tracing models [4-9] was used to validate the measured with the Lee model. The results show that the Lee model outperforms the FDTD and Ray Tracing models in both speed and accuracy. The propagation environment is quite unique and challenging for this deployment. The Lee model was used to optimize the coverage and minimize the interference while fine tuning radio parameters (antenna types, ERP, down tilt) to improve system performances. The net results were continuous connectivity with smooth roaming and high throughput which provided a different experience for users. Copyright ? 2013 by the Institute of Electrical and Electronic Engineers, Inc.EI
Enhanced Lee model from rough terrain sampling data aspect
No full textThe Lee propagation prediction model has been well recognized by the wireless industry as one of the most accurate propagation prediction models. This paper discusses innovative approaches dealing with rough digital samples of terrain data and enhancements to the Lee model during the validation process. In general, the Lee model is composed of two parts, the impact of man-made structures and the impact of the natural terrain variation [1-6]. There are other papers discuss innovative algorithms on calculating effective antenna gain [7,8] and diffraction loss [7-9] as well as on enhancing the Lee model [12-14]. This paper focuses on the natural (terrain) factor. The new algorithm presented in this paper is quite different than others as it integrates both Line Of Site (LOS) and shadow loss calculation together for the Lee model. First, in the LOS scenario, it addresses the issue of big swing of effective antenna gain due to non-continuous terrain data. Second, in the non-LOS situation, the effective antenna gain is integrated with shadow loss. Both single knife edge and multiple knife edge scenarios are discussed. The new algorithm is developed based on the analysis of measured and predicted (the theoretical shadow loss and effective antenna gain) data. The new algorithm involves more calculation but it improves the accuracy of the predicted value. This algorithm was implemented and verified using field terrain and measurement data from a variety of different environments and different countries including Italy, US, Spain, Japan, South Korea, Taiwan and Romania. ?2010 IEEE.EI
Synthesis of Co(3)O(4) nanowire arrays supported on Ni foam for removal of volatile organic compounds
No full textCrystalline Co3O4 nanowire arrays freely supported on Ni foam are successfully synthesized using a template-free method. The effects of reaction time, concentration of reactants, and temperature on the morphology of the nanowires are studied. The results indicate that uniform Co3O4 nanowires could be synthesized at 90 degrees C, and a transformation of the samples' morphology from nanoparticles to nanowires to microrods is observed by controlling the concentration of the reactants. The well-ordered nanowires synthesized under the selected reaction conditions are composed of spinel Co3O4 with diameters of 500-580 nm and lengths of 6-8 microm. These nanowires show good catalytic activity for the ozone catalytic oxidation of toluene.Hui, K. N.; Yin, Cui-Lei; Hui, K. S.; Lee, J. Y.; Li, M.; Lee, S. K.; Tsui, K. L.; Chao, Christopher Y H; Kwong, C. W
Possible involvement of phospholipase A(2) in light signal transduction of guard cells of Commelina communis
No full textPolyunsaturated fatty acids induce stomatal opening (Y. Lee, H. Lee, R. C. Crain, A. Lee and S. J. Kern. 1994. Cell Signal. 6: 181-186), but it is not known whether they function as second messengers in guard cells exposed to signals that open stomata. To test the hypothesis that phospholipase A(2)(PLA(2)), which produces fatty acids and lysophospholipids, is involved in light signal transduction in guard cells, we treated epidermal peels of Commelina communis L. with PLA(2) inhibitors and followed the changes in stomatal apertures in response to light. Stomatal opening by white, blue, or red light was inhibited by 2-3 different PLA(2) inhibitors in concentration ranges that have bren reported to inhibit PLA(2) activity. However, the PLA(2), inhibitors could not block stomatal opening induced by a polyunsaturated fatty acid. These results suggest that PLA(2) functions as a signal transducer for both blue and red light in guard cells.X118sciescopu
The Study of Androgen Effects on LPA-induced VEGF-C Expression in Prostate Cancer Cell Lines
No full textCortical actin filaments in guard cells respond differently to abscisic acid in wild-type and abi1-1 mutant Arabidopsis
No full textCortical actin filaments in guard cells of Commelina communis L. show signal-specific organization during stomatal movements [S.-O. Fun and Y. Lee (1997) Plant Physiol 115: 1491-1498; S.-O. fun and Y. Lee (2000) Planta 210: 1014-1017]. To study the roles of actin in signal transduction, it is advantageous to use Arabidopsis thaliana (L.) Heynh., an excellent model plant with numerous well-characterized mutants. Using an immunolocalization technique, we found that actin deployments in guard cells of A. thaliana were basically identical to those in C. communis: actin proteins were assembled into radial filaments under illumination, and were disassembled by ABA. In addition, we examined actin organization in an ABA-insensitive mutant (abil-1) to test the involvement of protein phosphatase 2C (PP2C) in the control of actin structure. A clear difference was observed after ABA treatment, namely, neither stomatal closing nor depolymerization of actin filaments was observed in guard cells of the mutant. Our results indicate that PP2C participates in ABA-induced actin changes in guard cells.X1120sciescopu
A high IIP2 direct-conversion mixer using an even-harmonic reduction technique for cellular CDMA/PCS/GPS applications
No full textThe authors wish to acknowledge FCI Quality &
Product Engineering team for measurement support, Dr.
K. H. Lim and Dr. S. Han for technical advice, and T. H.
Lee and K. Kim for software assistance
Manning, C. Y. : Confederate Service Record.
No full textThis service record is an account of military actions during the American Civil War by veteran C. Y. Manning.1 leaf ; 2 pdf pages.All descriptive lists and service records in this United Confederate (Civil War) Veterans manuscript collection believed to be based out of Robert E. Lee Camp #158 of the United Confederate Veterans (Fort Worth, Tex.).
United Confederate Veterans. R.E. Lee Camp No. 158 (Fort Worth, Tex.)The Southwest Collection Manuscript Record can be accessed at the following URL: http://www.lib.utexas.edu/taro/ttusw/00119/tsw-00119.htm
Electrochemical Detection of High-Sensitivity C-Reactive Protein Based on Biomimic Design of Electroactive Nanoassembly Multilayers
No full textIn this study, the gold electrode was modified with a ferrocene-terminated alkanethiol and phospholipid complex layer, which is designed and fabricated to serve as a C-reactive protein sensor using electrochemical determination. The scope of this research is to know whether a ferrocene-terminated self-assembled monolayer and hydrogenated phosphocholine hybrid bilayer could be used to perform C-reactive protein detection or not. After a series of experiments, the result shows that mixed electroactive SAM can facilitate electrons transferring from the solution to the electrode. And after coating phospholipids, this phenomenon seems to be hindered from the electrode. But this provoked small electrical signal of the recognition layer still allows for further usage. According to the result, it can be used to measure C-reactive protein and its electrochemical property and the changes of the electrode's electron transfer ability are characterized by cyclic voltammetry. This study demonstrates self-assembled ferrocene-terminated alkanethiol and phospholipid complex structure has potential as a C-reactive protein sensor and is stable to detect in the aqueous phase.補正完
- …
