Top PDF Stability of Large Flexible Satellite

Stability of Large Flexible Satellite

Stability of Large Flexible Satellite

ABSTRACT The stability rigid body main Direct for elastic intent the large the well Previous stable at bring forth an equilibrium the as a versa, and angle always 3 0 between unstable eq[r]

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Nonlinear stability of flows over rigid and flexible boundaries

Nonlinear stability of flows over rigid and flexible boundaries

A nother im p o rta n t mode-class identified by Sen & A rora is the ‘resonant’ (R) class. Modes in th is class are periodic over four cycles o f arg < j>yf, generally exhibit large c, (> 0.7), and exist only for large values of \(j>y,\^ B ifu rcatio n to regular R modes occurs via various tran sition al modes, periodic over two or three cycles o f arg <j >^. These modes may exh ib it characteristics o f the regular modes over parts of th e ir cycles. The TS to R bifurcatio n appears to occur via a singularity, and Sen & A rora conjecture th a t the concepts o f ‘m odal coalescence’ and ‘static divergence’ (see Carpenter & G arrad 1985) may be related to the behaviour o f modes near to this singularity. The appropriateness o f the term ‘resonant’ is m anifested by back-calculation o f the free-wave speed on the w all, which as Sen & A rora dem onstrate is m im icked closely by c^. The authors conclude, in som ething o f a departure from previous workers, th a t the TS and R modes should both be avoided rather than any attem pt made to stabilise them . They suggest th a t sm all values o f free-wave speed and dam ping offer the best prospect (by way o f compromise) for flow stabilisation.
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A Simple and Flexible Alternative to the Stability and Growth Pact Deficit Ceilings. Is it at hand?

A Simple and Flexible Alternative to the Stability and Growth Pact Deficit Ceilings. Is it at hand?

Buiter and Grafe (2003), in the context of enlargement, point out that the Pact needs to be re- oriented towards fiscal sustainability. They suggest a ‘permanent balance rule’ for taxation which ensures government solvency, which can be augmented to target a particular debt-GDP ratio. Whilst this proposal is simple, in contrast to the analysis presented here, this simplicity is deceptive. It does not confront the problem of political distortions in fiscal policy-making, except through the implicit assumptions made by policymakers on the future paths of government spending and its components. Announcing a sequence of deficit targets, whilst apparently more complex, forces the fiscal authorities and the Euro-12 group to confront the underlying assumptions about macroeconomic shocks (and their persistence) and can accommodate the possibility of both short, sharp recessions, which will require large deficits which are quickly reversed, and shallow periods of stagnation with output below potential for a number of years, which require a more gradual adjustment. It combines flexibility with commitment.
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The Suaineadh Project : A stepping stone towards the deployment of large flexible structures in space

The Suaineadh Project : A stepping stone towards the deployment of large flexible structures in space

There are three quantities the sensors must measure: linear acceleration, angular velocity and stability of the web. This is done through two main instruments: an inertial measurement unit (IMU), and a camera. There are five IMUs onboard the experiment: one on each of the four daughter sections, and a fifth in the central hub. The IMUs must measure the linear acceleration and rotational velocity of the five points on the web. The data from the daughter IMUs will allow the team to verify and compare against the computer simulations for the controlled deployment of the web. In a perfect deployment, the acceleration vector should be in the radial direction (i.e. centrifugal), and the rotational axis should be normal to the plane of the web (which itself should be confined to a 2D plane). Any disturbances from these ideal values represent either out of plane motion and/or errors or delays in the control (see Fig. Mission Stage Components in use Power
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A Stability Criterion Model of Flexible Footbridges under Crowd-Induced Vertical Excitation

A Stability Criterion Model of Flexible Footbridges under Crowd-Induced Vertical Excitation

Abstract: The excessive vibration caused by crowds walking across footbridges has attracted great public concerns in the past few decades. This paper presents, from considering the dynamic characteristics of the bipedal crowd model, a new stability limit criterion based on the bipedal excitation model. The stability limit can be used to estimate the upper boundary of crowd size. In addition, the dynamic stable performances of a structure, under a certain walking crowd size, can be predicted by the stability criterion. This proposed mechanism provides an alternative comprehension how crowd excite the excessive sway motion with a large-span structure.
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Attitude Control of a Flexible Satellite by Using Robust Control Design Methods

Attitude Control of a Flexible Satellite by Using Robust Control Design Methods

Designing satellites with various missions such as cli- matic, military, geology and astrological missions will cause the payloads being increased and as a result, the increase of their dimensions, weight and consumed pow- er. So, for more energy absorption, the effective sec- tion surface of satellite should be increased to installing more solar panels. On the other side, the existent limita- tions on satellites’ launch will cause the restriction on their volume and weight. To decrease the volume of sat- el- lites, they are designed as a concentrated structure with some supplemental parts which are fastened before launch and are opened after settlement in orbit, and to decrease the weight of satellites, the light materials are used in designing structures. The whole of these factors; means light weight, low volume and large section surface will cause the flexibility of satellites’ structure. In this case, preserving correct direction of main body and flexi- ble parts encounter with many challenges. According to these realities, many theoretical researches have been
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Long-term stability of TES satellite radiance measurements

Long-term stability of TES satellite radiance measurements

The Tropospheric Emission Spectrometer (TES) is a Fourier Transform Spectrometer on board the NASA Aura platform (Beer et al., 2001; Beer, 2006; Schoeberl et al., 2006). TES has a number of observational modes (e.g. global survey, step-and-stare, transect). The high spectral resolution of the instrument makes it very useful for identifying and quanti- fying trace atmospheric gases, among which are ozone, car- bon monoxide, methane, and ammonia. The user community consists of researchers interested in global air quality and cli- mate change. This study utilizes observations in global sur- vey mode, where TES makes measurements along the satel- lite track with a spacing of ∼ 180 km. TES nadir spectra have 0.06 cm −1 unapodized spectral resolution with footprints of 8 × 5 km 2 resulting from the averages of 16 element detector arrays where each detector has a 0.5 × 5 km 2 nadir footprint. The TES spectral range is covered by four filters: 2B1 (650– 900 cm −1 ), 1B2 (920–1150 cm −1 ), 2A1 (1100–1340 cm −1 ) and 1A1 (1900–2250 cm −1 ). The noise characteristics for each band are taken from Worden et al. (2006), and are listed in Table 1. In general, bands 1B2 and 2A1 have the low- est Noise Equivalent Detector Temperature (NEDT) values, band 2B1 has a slightly higher value and band 1A1 is the most noisy. In an analysis such as this, with the assumption of pure white (Gaussian) noise, there should be no expec- tation of bias on the average results given the large number
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Bending stability of Cu0 4CrO2   A transparent p type conducting oxide for large area flexible electronics

Bending stability of Cu0 4CrO2 A transparent p type conducting oxide for large area flexible electronics

FIG. 3. (a) Resistance and normalised change in resistance ((R − R o )/R o ) for successive tensile strain bending cycles of a 25nm ( • ) and 90nm () thick Cu 0.4 CrO 2 film. The maximum applicable strain of 0.8% (r=5mm) was used. (b) (R − R o )/R o of 25nm ( • ) and 90nm (H) samples under equivalent compressive stress. The values for the compressive bending cycles saturate for the thicker sample at the operational limit of our electrical measurement system. (c) Scanning Electron Microscopy (SEM) of a 90nm sample on polyimide film after 2000 bending cycles. To expose potential cracking of the film the sample was mounted under equivalent tension; (d) Isolated delaminated area seen in a 25nm sample after 10 manual bending cycles (tension, 5mm). (e) Large scale (top) in SEM image of Cu 0.4 CrO 2 on polyimide film after a single compressive strain cycle; the magnified SEM image (bottom) of a crack seen above. (f) Schematic of the sample morphology. The thinner samples are more susceptible to delamination, as the film roughness is comparable to the thickness, thus creating isolated weak points (see arrow). (g) Schematic of different morphology of faults created under compression and tension.
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Optimal Load of Flexible Joint Mobile Robots Stability Approach

Optimal Load of Flexible Joint Mobile Robots Stability Approach

kinematically redundant manipulators. Korayem and Ghariblu [6] developed an algorithm for finding the DLCC on rigid mobile manipulators. In their work the stability and flexibility are not taken into account. Also, some researchers have studied the stability of mobile manipulators. Some of the earlier work discussed only the static stability [7-8] and some others were concerned with the dynamic stability [9-10]. Moreover, there is some research work on carrying heavy loads or application of large forces by mobile manipulators [11]. But, none of these works has considered the DLCC finding on mobile manipulators.
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Large-scale increases in vegetation productivity inferred from satellite data

Large-scale increases in vegetation productivity inferred from satellite data

climate and affecting food production. The characterization of large-scale increases in vegetation productivity will lead to a better understanding of the distribution and dynamics of carbon sources/sinks and climate change. In this dissertation, I examined the increases in vegetation productivity at multiple scales. First, I examined the increases in vegetation productivity and their associations with climate variability at the global scale over the period 1982 to 1998 using satellite data and ground-based climatology data. Temperature, and, in particular spring warming, was the primary climatic factor associated with greening in the northern high latitudes, Western Europe, U.S. Pacific Northwest, tropical and subtropical Africa, and eastern China. Precipitation was a strong correlate of greening in fragmented regions only. Globally, greening trends are a function of both climatic and non-climatic factors, such as forest regrowth, CO 2 enrichment,
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LARGE SCALE SATELLITE IMAGE PROCESSING USING HADOOP DISTRIBUTED SYSTEM

LARGE SCALE SATELLITE IMAGE PROCESSING USING HADOOP DISTRIBUTED SYSTEM

In the internet service data base is most important part in that database image are stored in the world large data of images so that handling is very difficult just like ,the duplication of image it’s increases the data size .We are all known about if that data was big the processing time also more With the proliferation of online photo storage and social media from websites such as Facebook and Picasa, the amount of image data available is larger than ever before and growing more rapidly every day . the billions of images available to us on the web. These images are improve, however, by the fact that users are supplying tags (of objects, faces, etc.), comments, titles and descriptions of this data for us. This information produces with an amazing amount of unprecedented context for images. The idea can be applied to a wider range of image features that allow us to examine and analyze images in a revolutionary way. The current processing of images goes through ordinary sequential ways to accomplish this job. The program loads image after image, The processing of data today is done by using oracle versions such as 9i,10G or by any another DBMS software. But with the increasing usage of internet all over the world the data on net is increasing rapidly. So, the processing of mass data is not possible by using any oracle software or any another existing DBMS software. the report generated after analysis will help the user to know about his usage. For analyzing the data & images we are going to use Hadoop technology.
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LARGE SCALE SATELLITE IMAGE PROCESSING USING HADOOP DISTRIBUTED SYSTEM

LARGE SCALE SATELLITE IMAGE PROCESSING USING HADOOP DISTRIBUTED SYSTEM

[9] A. Parulekar, R. Datta, J. Li, and J. Z. Wang. Large-scale satellite image browsing using automatic semantic categorization and content- based retrieval. In Proc. ICCV’2005 Workshop on Semantic Knowledge in Computer Vision , pages 1873–11880, Beijing, China, October 2005 [10] G. G. Wilkinson. Results and implications of a study of fifteen years of satellite image classification experiments. IEEE Trans. on Geoscience and Remote Sensing, 43(3):433– 440, 2005

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Quorum: Providing Flexible Quality of Service for Large-Scale Internet Services

Quorum: Providing Flexible Quality of Service for Large-Scale Internet Services

Both research and commercial Internet service com- munities have explored hardware-based and software- based approaches to meeting this QoS challenge. A sim- ple and effective hardware-based approach is to rely on an over-provisioning and physical partitioning of clus- ter nodes, each partition dedicated to a different class of service. Unfortunately, the necessity to handle large and unpredictable fluctuations in load cause these techniques to incur in potentially high cost (enough resource must be available in each partition to handle load spikes) and low resource utilization (the extra resources are idle be- tween spikes). Moreover, such a static approach does not offer much flexibility in the event services are added or upgraded, or more problematically, QoS guarantees are changed. A change in conditions frequently re- quires hardware reconfiguration, which may be expen- sive and/or error prone.
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Stability Analysis on Power System with Large  Power Source

Stability Analysis on Power System with Large Power Source

There are 8 generators in the base 5; a total of 4800MW active power is transmitted by four-loop transmission lines. When N-2 failure occurs within these transmission lines, the relay will remove the failure side of the line 0.09s after the fault and remove the other side of the same line as well as the other parallel line 0.01 s later. Because of the loss of two lines, large amount of power can’t be transmitted outside, which will lead to the con- tinuous accumulation of the generator kinetic energy and the transient energy will be spread to the external system. Because of the loss of two lines, a large amount of power can’t be transmitted outside, which lead to the continuous accumulation of the generator kinetic energy. The tran- sient energy will be spread to the external system. The system 3 is in the state of a large amount of power short- fall and in order to maintain the energy balance of system 3 a great quantity of power of system 5 will be forced to flow to the system 3. The voltage across line 6 continues to drop and eventually system 3 and system 5 will be disconnected when the low voltage disconnecting limit is reached.
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Maximum Allowable Dynamic Load of Flexible Manipulators Undergoing Large Deformation

Maximum Allowable Dynamic Load of Flexible Manipulators Undergoing Large Deformation

The dynamic analysis of high speed mechanisms, space robot arms and exible structures has received consid- erable attention in the past two decades. Most of the researchers, however, assume small deformation and use a linear strain displacement relationship. When accurate mathematical models are required, nonlin- ear elastic deformation in structures may have to be considered. Nonlinearities can arise out of nonlinear elastic, plastic and viscoelastic behavior, or there can be geometric nonlinearities arising out of large deformations.

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FlashFry: a fast and flexible tool for large-scale CRISPR target design

FlashFry: a fast and flexible tool for large-scale CRISPR target design

Results: Here, we introduce FlashFry, a fast and flexible command-line tool for characterizing large numbers of CRISPR target sequences. With FlashFry, users can specify an unconstrained number of mismatches to putative off- targets, richly annotate discovered sites, and tag potential guides with commonly used on-target and off-target scoring metrics. FlashFry runs at speeds comparable to commonly used genome-wide sequence aligners, and output is provided as an easy-to-manipulate text file.

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Improvement in Large Signal Stability Using PSO Algorithm

Improvement in Large Signal Stability Using PSO Algorithm

In this thesis, the performance of PSS and PSOPSS is compared and analyzed for Single machine infinite bus system (SMIB) and 3-machine system. The gain of the PSS is set by applying particle swarm optimization (PSO) optimization technique. This can enhance the angle stability and provide the voltage regulation at the generator terminals. Transient stability analysis is used to investigate the stability of a power system under sudden and large disturbances with PSS and PSOPSS

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Dynamic, scalable and flexible resource discovery for large-dimension many-core systems

Dynamic, scalable and flexible resource discovery for large-dimension many-core systems

The overhead starts to reduce after reaching the maximum due to the increasing number of remote directories that provide in- formation about other alternative resources and also the increase of the replication of the resources. Interestingly, in a second configuration that we have simulated for a congested network with 50 percent of the nodes as concurrent requesters, the results show a significant decrease in the discovery overhead. The rea- son for this overhead reduction is that when we perform several queries concurrently by di ff erent distributed RD components (i.e., resource requesters), the probability tables of intermediate directories (QMS nodes) would dynamically be updated accord- ing to each discovery result. This will improve the degree of resource awareness in the probability tables in the directories which would lead to the reduction of the discovery overhead (i.e., reducing the number of forwarding and query dissemination) compared to the first configuration. Moreover, implementation of the resource caching mechanism in the nodes of di ff erent types (either LN, AN or SN nodes) enables the general nodes to store the experience of successful queries for a specific period of time which facilitates the resolving of similar queries from other requesters with less overhead cost. In both configurations the overhead variations are reasonably small for large network sizes. Therefore the overhead should not be dependent on the network size which means that our RD solution is scalable.
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Rapid modelling of the large scale magnetospheric field from Swarm satellite data

Rapid modelling of the large scale magnetospheric field from Swarm satellite data

As part of the European Space Agency (ESA) Swarm mission, ESA has commissioned an independent scientific consortium known as the Swarm satellite Constellation Application and Research Facility (SCARF) to develop and operate the Level 2 Processor (L2PS). Its purpose is to derive high quality scientific products from the mission’s data. One such product is the Fast-Track Magnetospheric Model (FTMM), which is a model of the large scale vector magnetospheric field and its induced counterpart. This model is generated once per satellite orbit, in near real-time by a robust, autonomous algorithm. Its intended use is similar to that of the Disturbance storm time Index (Dst): characterising the rapidly varying magnetospheric field, as an input to other global field models, and for the space weather community. In this paper we describe in detail the FTMM algorithm and assess its ability to recover the magnetospheric component from the consortium’s test satellite data set as well as real data from the CHAMP satellite.
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NOBLE - Flexible concept recognition for large-scale biomedical natural language processing

NOBLE - Flexible concept recognition for large-scale biomedical natural language processing

Annotator (DLA), and cTAKES Fast Dictionary Lookup Annotator (FDLA). Because NOBLE Coder was origin- ally written to replace MMTx in our TIES system, we chose to evaluate MMTx rather than its Prolog analog, MetaMap. As described by its NLM developers [9], MMTx is a Java implementation of MetaMap, which produces only minor differences in comparison. These discrepancies result in large part from MMTx’s tokeniza- tion and lexicalization routines. MMTx continues to be widely used throughout the biomedical informatics com- munity, in part because of (1) its simpler installation using a single server and (2) its more flexible vocabulary building process.
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