scholarly journals Precise Control of Beam Formation for Mobile Communication Satellites Based on On-board Measurements of the Shape of the Large Reflector Surface

2019 ◽  
Vol 17 (1) ◽  
pp. 33-38
Author(s):  
Maki AKIOKA ◽  
Amane MIURA ◽  
Teruaki ORIKASA ◽  
Hiroyuki TSUJI ◽  
Morio TOYOSHIMA ◽  
...  
Keyword(s):  
Mobile Communication ◽  
Precise Control ◽  
Beam Formation ◽  
Reflector Surface

scholarly journals Selective Mobile Communication within a Coverage Area Bounded by Radiating Cables

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Hatim Behairy ◽  
Waleed Alrobian ◽  
Adnan Alghammas ◽  
Amr Alasaad ◽  
Brian Suter ◽  
...  
Keyword(s):  
Mobile Phone ◽  
Mobile Devices ◽  
Mobile Phones ◽  
Mobile Communication ◽  
Mobile Services ◽  
Directional Antennas ◽  
Base Station ◽  
Coverage Area ◽  
Precise Control ◽  
Novel Technique

It is often desirable to control mobile phone services in areas where complete silence is either expected or mandatory, including schools, places of worship, hospitals, and prisons. In contrast to conventional techniques, such as jammers or Faraday cages, we present a novel technique to selectively control mobile phone services within a desired area. Our solution enables the area’s keeper to allow mobile phones on a whitelist to freely use mobile services without disruption while denying services to all other mobile phones that are within the boundaries of the desired area to be controlled. Our solution uses a base station controller to identify all mobile devices located within the area to be controlled, while an antenna is placed inside the area to attract all mobile devices in the area to connect to the base station controller. In previous work, we proposed a system that uses directional antennas for the attraction technique. In this work, we show that replacement of the directional antennas with a leaky feeder antenna enables more accurate control of mobile phone services in and around the area to be controlled. Simulations and experiments of the leaky feeder technique confirm its precise control of mobile phone services within the desired areas.

A New Best-Fit Method for Distorted Reflector Antenna Surface

2013 ◽  
Vol 336-338 ◽  
pp. 1857-1862
Author(s):  
Wen Wen Chang ◽  
Ai Li Yusup ◽  
Bin Bin Xiang
Keyword(s):  
Least Square Method ◽  
Element Model ◽  
Reflector Antenna ◽  
Least Square ◽  
Precise Control ◽  
Antenna Performance ◽  
Fitting Method ◽  
Reflector Surface ◽  
Best Fitting ◽  
Antenna Surface

Actual reflector antenna always has a deformation which has a serious influence on antenna performance. Establishing the equation of the distorted reflector surface is important for calculating antenna performance and precise control. A new best-fitting method based on least square method is submitted in this paper. This method depart from the ideal parabolic equation, and use the distance between the deformation point and the correspondent fitting point to establish the least square error condition equations, though which the six parameters can be got to determine the geometry position of the deformed parabolic accurately. Matrix operation can make the algorithm easy to realize in computer. Nan-shan 25m antennas finite element model is established in ANSYS program, and its result is analyzed compared with another method, confirmed the operability and accuracy of this algorithm.

A Novel Reconstitution Method for Inducing the Formation of Regular 2-Dimensional Arrays of Membrane Proteins and Lipids

1988 ◽  
Vol 46 ◽  
pp. 152-153 ◽  
Author(s):  
A. Engel ◽  
A. Holzenburg ◽  
K. Stauffer ◽  
J. Rosenbusch ◽  
U. Aebi
Keyword(s):  
Membrane Proteins ◽  
Flow Rate ◽  
Lipid Membranes ◽  
Functional Characterization ◽  
Dimensional Structure ◽  
Electron Crystallography ◽  
Peltier Element ◽  
Protein Ratio ◽  
Precise Control ◽  
3 Dimensional

Reconstitution of solubilized and purified membrane proteins in the presence of phospholipids into vesicles allows their functions to be studied by simple bulk measurements (e.g. diffusion of differently sized solutes) or by conductance measurements after transformation into planar membranes. On the other hand, reconstitution into regular protein-lipid arrays, usually forming at a specific lipid-to-protein ratio, provides the basis for determining the 3-dimensional structure of membrane proteins employing the tools of electron crystallography.To refine reconstitution conditions for reproducibly inducing formation of large and highly ordered protein-lipid membranes that are suitable for both electron crystallography and patch clamping experiments aimed at their functional characterization, we built a flow-dialysis device that allows precise control of temperature and flow-rate (Fig. 1). The flow rate is generated by a peristaltic pump and can be adjusted from 1 to 500 ml/h. The dialysis buffer is brought to a preselected temperature during its travel through a meandering path before it enters the dialysis reservoir. A Z-80 based computer controls a Peltier element allowing the temperature profile to be programmed as function of time.

Multiple-fracturing and viewing of the same frozen sample at different depths using a low temperature FESEM

1996 ◽  
Vol 54 ◽  
pp. 820-821
Author(s):  
M.V. Parthasarathy ◽  
C. Daugherty
Keyword(s):  
Temperature Field ◽  
Low Temperature ◽  
Field Emission ◽  
Multiple Fracture ◽  
Precise Control ◽  
Cold Stage ◽  
Different Depths ◽  
Transfer Device

The versatility of Low Temperature Field Emission SEM (LTFESEM) for viewing frozen-hydrated biological specimens, and the high resolutions that can be obtained with such instruments have been well documented. Studies done with LTFESEM have been usually limited to the viewing of small organisms, organs, cells, and organelles, or viewing such specimens after fracturing them.We use a Hitachi 4500 FESEM equipped with a recently developed BAL-TEC SCE 020 cryopreparation/transfer device for our LTFESEM studies. The SCE 020 is similar in design to the older SCU 020 except that instead of having a dedicated stage, the SCE 020 has a detachable cold stage that mounts on to the FESEM stage when needed. Since the SCE 020 has a precisely controlled lock manipulator for transferring the specimen table from the cryopreparation chamber to the cold stage in the FESEM, and also has a motor driven microtome for precise control of specimen fracture, we have explored the feasibility of using the LTFESEM for multiple-fracture studies of the same sample.

Mobile Communication Technologies, for Good and for Ill

PsycCRITIQUES ◽  
2009 ◽  
Vol 54 (19) ◽  
Author(s):  
Stuart Fischoff
Keyword(s):  
Mobile Communication ◽  
Communication Technologies

Pharmacokinetics and Haemostatic Status During Consecutive Infusions of Recom binant Tissue-Type Plasminogen Activator in Patients with Acute Myocardial Infarction

1989 ◽  
Vol 61 (03) ◽  
pp. 497-501 ◽  
Author(s):  
E Seifried ◽  
P Tanswell ◽  
D Ellbrück ◽  
W Haerer ◽  
A Schmidt
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Plasminogen Activator ◽  
Peak Plasma ◽  
Peak Plasma Concentration ◽  
Tissue Type ◽  
Tissue Type Plasminogen Activator ◽  
Precise Control ◽  
Type Plasminogen Activator

SummaryPharmacokinetics and systemic effects of recombinant tissue type plasminogen activator (rt-PA) were determined during coronary thrombolysis in 12 acute myocardial infarction patients using a consecutive intravenous infusion regimen. Ten mg rt-PA were infused in 2 minutes resulting in a peak plasma concentration (mean ±SD) of 3310±950 ng/ml, followed by 50 mg in 1 h and 30 mg in 1.5 h yielding steady state plasma levels of. 2210±470 nglml and 930±200 ng/ml, respectively. All patients received intravenous heparin. Total clearance of rt-PA was 380±74 ml/min, t,½α was 3.6±0.9 min and t,½β was 16±5.4 min.After 90 min, in plasma samples containing anti-rt-PA-IgG to inhibit in vitro effects, fibrinogen was decreased to 54%, plasminogen to 52%, α2-antiplasmin to 25%, α2-macroglobulin to 90% and antithrombin III to 85% of initial values. Coagulation times were prolonged and fibrin D-dimer concentrations increased from 0.40 to 2.7 μg/ml. It is concluded that pharmacokinetics of rt-PA show low interpatient variability and that its short mean residence time in plasma allows precise control of therapy. Apart from its moderate effect on the haemostatic system, rt-PA appears to lyse a fibrin pool in addition to the coronary thrombus.

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