Launch Location Research Articles

Calculation of the main operational characteristics of a tethered high-altitude ship-based system

Objectives. Currently, UAVs are actively used in many military and civilian fields such as object surveillance, telecommunications, radar, photography, video recording, and mapping, etc. The main disadvantage of autonomous UAVs is their limited operating time. The long-term operation of UAVs on ships can be ensured by tethered high-altitude systems in which the power supply of engines and equipment is provided from the onboard energy source through a thin cable tether. This paper aims to select and justify the appearance of such system, as well as to calculate the required performance characteristics.Methods. The study used methods of systemic and functional analysis of tethered system parameters, as well as methods and models of the theory of relations and measurement.Results. The issues of design and implementation of new generation tethered high-altitude ship-based systems were considered. A rational type of aerodynamic design for unmanned aerial vehicles was determined based on existing tethered platforms. The optimal architecture of the tethered system was defined and justified. The paper presents the appearance and solution for placement onboard the ship, and describes its operation. The main initial parameters for designing high-altitude systems such as take-off weight, optimal lift altitude, maximum power required for operation, structure of the energy transfer system, as well as deployment and lift time to the design altitude were selected and calculated.Conclusions. The methodology for calculating the necessary characteristics described in the paper can be used for developing and evaluating tethered high-altitude systems. These systems are capable of performing a wide range of tasks, without requiring a separate storage and launch location, which is especially important in the ship environment. The system presented herein possesses significant advantages over well-known analogues.

Fireworks: A Potential Artificial Source for Imaging Near-Surface Structures

Abstract Seismic waves induced by incident acoustic waves from air disturbances can be used to image near-surface structures. In this article, we analyze seismic waveforms recorded by a dense array on the Xishancun landside in Li County, Sichuan Province, southwest China during the Lunar New Year’s Eve (27 January 2017). A total of eight event clusters have been identified as a result of firework explosions. For each cluster, which comprises dozens of individual events with high similarity, we manually pick arrival times of the first event recorded by the array and locate it with a grid-search method. We then rotate three-component waveforms of all events from the east, north, and vertical coordinate system to the local LQT coordinates (L, positive direction perpendicular to the landslide surface and pointing downwards; Q, positive direction is from the launch location of firework to the station along the landslide surface; T, perpendicular to the plane formed by the L and Q directions, and the selected positive direction of the T axis makes LQT form the left-hand coordinate system), and stack the LQT components for those events with cross-correlation values CC ≥ 0.8 with respect to the first event. Characteristics of the stacked LQT components are also examined. The particle motions at each station are retrograde ellipse in the frequency range of ∼5–50 Hz, suggesting air-coupled Rayleigh waves generated by the firework explosions. Spectrograms of the Rayleigh waves also show clear dispersions, which might be used to image near-surface velocity structures. Although we cannot directly extract the phase velocities due to the limitation of the seismic array, our study shows that the fireworks might provide a low-cost and easy-to-use seismic source for imaging near-surface structures.

Branched flows of flexural elastic waves in non-uniform cylindrical shells.

Propagation of elastic waves along the axis of cylindrical shells is of great current interest due to their ubiquitous presence and technological importance. Geometric imperfections and spatial variations of properties are inevitable in such structures. Here we report the existence of branched flows of flexural waves in such waveguides. The location of high amplitude motion, away from the launch location, scales as a power law with respect to the variance, and linearly with respect to the correlation length of the spatial variation in the bending stiffness. These scaling laws are then theoretically derived from the ray equations. Numerical integration of the ray equations also exhibit this behaviour-consistent with finite element numerical simulations as well as the theoretically derived scaling. There appears to be a universality for the exponents in the scaling with respect to similar observations in the past for waves in other physical contexts, as well as dispersive flexural waves in elastic plates.

A logic-based Benders decomposition method for the multi-trip traveling repairman problem with drones

This paper considers the problem of delivering a certain number of packages to a set of customers using multiple drones dispatched from a single truck. Once a drone delivers a package, it returns to the truck to pick up another package while the truck waits at the launch location. The aim is to determine the truck route and the sequence of drone trips from the truck such that all the customer demands are served, either by the truck or drones, to minimize the sum of customer waiting times. We propose a new formulation of this problem based on an extended graph network representation. A new logic-based Benders decomposition method enhanced with relaxations is also developed and evaluated on several benchmark instances. The numerical results show that the proposed exact method obtains optimal solutions to the majority of the problem instances within the time limit of one hour.

User Acceptance Test for Kaaba Buku Saku Application

As one of the countries with a big Muslim population in the world, opportunity of growing an Islamic business in Indonesia has swiftly gained. It is proved by the growth of 95% market share in manufacture, service, and technology areas. This will give a chance for entrepreneurs to follow the wave. One of the entrepreneurs that utilized the opportunity is the developer of Kaaba Buku Saku application. They are releasing solutions for Muslims in a form of mobile applications. Since the launching of this application, Kaaba Buku Saku generates only 30% active user from the total downloader. By using Binary Logistic Regression, it is known that Facilitating Conditions was a significant variable that means the customer would prefer to adopt the application when they have a sufficient resources and knowledge to adopt it. From the customer journey map, it is known that the improvements that should be made by the developer are equipped the prayer time feature with automatically locate feature, adjust the highlight content to be more understandable, launch live location feature for Hajj and Umrah users, give a step by step guidance for the first use, give notification to calibrate the phone for Qibla feature, and the last is launch their iOS version application.
 Keywords: Muslim-based mobile application, Kaaba buku saku, binary logistic regression, customer journey map

Joint optimization of customer location clustering and drone-based routing for last-mile deliveries

With growing consumer demand and expectations, companies are attempting to achieve cost-efficient and faster delivery operations. The integration of autonomous vehicles, such as drones, in the last-mile network design can curtail many operational challenges and provide a competitive advantage. This paper deals with the problem of delivering orders to a set of customer locations using multiple drones that operate in conjunction with a single truck. To take advantage of the drone fleet, the delivery tasks are parallelized by concurrently dispatching the drones from a truck parked at a focal point (ideal drone launch location) to the nearby customer locations. Hence, the key decisions to be optimized are the partitioning of delivery locations into small clusters, identifying a focal point per cluster, and routing the truck through all focal points such that the customer orders in each cluster are fulfilled either by a drone or truck. In contrast to prior studies that tackle this problem using multi-phase sequential procedures, this paper presents mathematical programming models to jointly optimize all the decisions involved. We also consider two polices for choosing a cluster focal point - (i) restricting it to one of the customer locations, and (ii) allowing it to be anywhere in the delivery area (i.e., a customer or non-customer location). Since the models considering unrestricted focal points are computationally expensive, an unsupervised machine learning-based heuristic algorithm is proposed to accelerate the solution time. Initially, we treat the problem as a single objective by independently minimizing either the total cost or delivery completion time. Subsequently, the two conflicting objectives are considered together for obtaining the set of best trade-off solutions. An extensive computational study is conducted to investigate the impacts of restricting the focal points, and the influence of adopting a joint optimization method instead of a sequential approach. Finally, several key insights are obtained to aid the logistics practitioners in decision making.

Impacts of Convergence on Structure Functions from Surface Drifters in the Gulf of Mexico

AbstractThere are limitations in approximating Eulerian statistics from surface drifters, due to biases from surface convergences. By contrasting second- and third-order Eulerian and surface drifter structure functions obtained from a model of the Gulf of Mexico, the consequences of the semi-Lagrangian nature of observations during the summer Grand Lagrangian Deployment (GLAD) and winter Lagrangian Submesoscale Experiment (LASER) are estimated. By varying launch pattern and location, the robustness and sensitivity of these statistics are evaluated. Over scales less than 10 km, second-order structure functions of surface drifters consistently have shallower slopes (~r2/3) than Eulerian statistics (~r), suggesting that surface drifter structure functions differ systematically and do not reproduce the scalings of the Eulerian fields. Medians of Eulerian and cluster release second-order statistics are also significantly different across all scales. Synthetic cluster release statistics depend on launch location and weakly on launch pattern. The observations suggest little seasonal difference in the second-order statistics, but the LASER third-order structure function shows a sign change around 1 km, while GLAD and the synthetic cluster releases show a third-order structure function sign change around 10 km. Further, synthetic surface drifter cluster releases (and therefore likely the GLAD observations) show robust biases in the negative third-order structure functions, which may lead to significant overestimation of the spectral energy flux and underestimation of the transition scale to a forward energy cascade. The Helmholtz decomposition, and curl and divergence statistics, of Eulerian and cluster releases differ, particularly on scales less than 10 km, in agreement with observations of drifters preferentially sampling convergences in coherent structures.

Efficiency in Carrying Cargo to Earth Orbits: Spaceports Repositioning

Space flights are in these days not any more question of technology, but more question of costs. One way how to decrease cost of launch is change of home spaceport. Change of home spaceport for different rockets is a way to achieve more efficient launches to space. The reason is different acceleration achieved from Earth rotation. We added several mathematical calculations of missions to Low Earth Orbit and Geostationary Earth Orbit to show bonuses from Earth rotation and effect of atmospheric drag on specific rockets used these days. We discussed only already used space vessels. Namely Arianne 5, Delta 4 heavy, Proton-M, Zenit and Falcon9. For reaching GEO we discuss possibility of using Hohmman transfer, because none of aforementioned vessels is available for direct GEO entry. As possible place for launch we discussed spaceports Baikonur, Kennedy Space center, Guyana Space center and Sea Launch platform. We present results in form of additional acceleration for each spaceport, and we also project this additional acceleration in means payload increase. In conclusion we find important differences between vessel effectivity based on spaceport used for launch. Change of launch location may bring significant cost decrease for operators.

Influences of initial launch conditions on flight performance of high altitude balloon ascending process

Influences of initial launch conditions on flight performance are addressed for the high altitude balloon ascending process. A novel dynamic model was established to describe thermodynamic and kinetic characteristics of balloon which consists of atmospheric, thermal and dynamic submodels. Based on the model, ascending processes of a high altitude balloon under different initial launch conditions were simulated. The initial launch conditions were classified into three types: inflating quantity, launch time and launch position. The ascending velocity and the differential pressure were defined and used as evaluation parameters of flight performance. Results showed that the inflating quantity is the most effective factor for ascending process, and the upper and lower limits were also proposed separately from safety and performance perspectives. For both launch time and launch location conditions, different solar radiation is the main effect approach during ascending process. Specifically, the influence mechanism of launch time in one day and launch longitude are completely identical due to the Earth’s rotation. Results also showed that the sunset process is the optimal selection for safety of balloon and efficient utilization of solar energy. Due to the Earth’s revolution, the influence mechanism of launch date and launch latitude are identical and the effects are more seasonal and less effective. Launch time and location should be considered comprehensively in practical operation of ballooning.

Infrasonic energy from orbital launch vehicles

Large, heavy-lift rockets have significant acoustic and infrasonic energy that can often be detected from a considerable distance. These sounds, under certain environmental conditions, can propagate hundreds of kilometers from the launch location. Thus, ground-based infrasound arrays can be used to monitor the low frequencies emitted by these large rocket launches. Multiple launches and static engine tests have been successfully recorded over many years using small infrasound arrays at various distances from the launch location. Infrasonic measurements using a 20 m array and parabolic equation modeling of a recent launch of an Aries V rocket at Wallops Island, Virginia, will be discussed.

Observing System Simulation Experiments of cross-layer Lagrangian data assimilation

We conduct Observing System Simulation Experiments (OSSEs) with Lagrangian data assimilation (LaDA) in two-layer point-vortex systems, where the trajectories of passive tracers (drifters or floats) are observed on one layer that is coupled to another layer with different dynamics. Depending on the initial position of the observed tracers, the model studied here can exhibit nonlinear features that cause the standard Kalman filter and its variants to fail. For this reason, we adopt a Monte Carlo approach known as particle filtering, which takes the nonlinear dynamics into account. The main objective of this paper is to understand the effects of drifter placement and layer coupling on the precision skill of assimilating Lagrangian data into multi-layered models. Therefore, we analyze the quality of the assimilated vortex estimates by assimilating path data from passive tracers launched at different locations, on different layers and in systems with various coupling strengths between layers. We consider two cases: vortices placed on different layers (heton) and on the same layer (non-heton). In both cases we find that launch location, launch layer and coupling strength all play a significant role in assimilation precision skill. However, the specifics of the interplay of these three factors are quite different for the heton case versus the non-heton case.

Laser guide star wavefront sensing for ground-layer adaptive optics on extremely large telescopes

We propose ground-layer adaptive optics (GLAO) to improve the seeing on the 42 m European Extremely Large Telescope. Shack-Hartmann wavefront sensors (WFSs) with laser guide stars (LGSs) will experience significant spot elongation due to off-axis observation. This spot elongation influences the design of the laser launch location, laser power, WFS detector, and centroiding algorithm for LGS GLAO on an extremely large telescope. We show, using end-to-end numerical simulations, that with a noise-weighted matrix-vector-multiply reconstructor, the performance in terms of 50% ensquared energy (EE) of the side and central launch of the lasers is equivalent, the matched filter and weighted center of gravity centroiding algorithms are the most promising, and approximately 10×10 undersampled pixels are optimal. Significant improvement in the 50% EE can be observed with a few tens of photons/subaperture/frame, and no significant gain is seen by adding more than 200 photons/subaperture/frame. The LGS GLAO is not particularly sensitive to the sodium profile present in the mesosphere nor to a short-timescale (less than 100 s) evolution of the sodium profile. The performance of LGS GLAO is, however, sensitive to the atmospheric turbulence profile.

A new ball launching system with controlled flight parameters for catching experiments

Systematic investigations of sensorimotor control of interceptive actions in naturalistic conditions, such as catching or hitting a ball moving in three-dimensional space, requires precise control of the projectile flight parameters and of the associated visual stimuli. Such control is challenging when air drag cannot be neglected because the mapping of launch parameters into flight parameters cannot be computed analytically. We designed, calibrated, and experimentally validated an actuated launching apparatus that can control the average spatial position and flight duration of a ball at a given distance from a fixed launch location. The apparatus was constructed by mounting a ball launching machine with adjustable delivery speed on an actuated structure capable of changing the spatial orientation of the launch axis while projecting balls through a hole in a screen hiding the apparatus. The calibration procedure relied on tracking the balls with a motion capture system and on approximating the mapping of launch parameters into flight parameters by means of polynomials functions. Polynomials were also used to estimate the variability of the flight parameters. The coefficients of these polynomials were obtained using the launch and flight parameters of 660 launches with 65 different initial conditions. The relative accuracy and precision of the apparatus were larger than 98% for flight times and larger than 96% for ball heights at a distance of 6 m from the screen. Such novel apparatus, by reliably and automatically controlling desired ball flight characteristics without neglecting air drag, allows for a systematic investigation of naturalistic interceptive tasks.

Lagrangian predictability assessed in the East China Sea

A group of 30 surface drifters, launched over a 4 day period as part of a US Navy exercise in early October 2007, are used to assess the predictability of trajectories in a confined geographic region at the northwestern edge of the Kuroshio north of Taiwan. Model trajectories were computed from archives of hourly hindcast velocities from the US Navy East Asian Seas (EAS16) model with 1/16° horizontal resolution. Three metrics are defined for comparing observed and modeled trajectories. All three metrics indicated that model trajectories separated from observations by roughly 15 km after the first 24 h on average. Because of the unique launch strategy for these drifters, with six repetitions of launches from four locations, the dependence of predictability on both launch time and launch location could be assessed separately. Predictive skill displayed only modest dependence on launch time, likely influenced by the passage of a typhoon near the experiment area a few days prior to the first drifter launch. Launch location was a much more reliable indicator of predictive skill, with trajectories for launches closest to the edge of the Kuroshio typically hardest to predict, and those for launches on the shelf, where currents tended to be weaker, predicted more accurately. Comparisons of skill metric statistics for modeled trajectories from hindcasts with and without tides suggested that tidal currents have only a small impact on predictive skill. The influence of archive time and space resolution was also studied using sets of model trajectories computed from hindcast archives that were systematically subsampled separately in space and time. Coarsening by up to a factor of eight in either space or time had little impact on predictive skill. Further coarsening degraded trajectory predictions, particularly when coarsening in time leads to an archive time step too large to adequately resolve the tides. While accurate trajectory predictions remain challenging for ocean models, skill assessments like the one presented here are important for developing error estimates for users of trajectory forecasts and for gaining new insight into potential sources of model errors.

Impact of laser launch location on the performance of laser tomography and multiconjugate adaptive optics for extremely large telescopes

Laser tomography and multiconjugate adaptive optics are under development for ground-based extremely large telescopes. Continuous wave sodium guide star lasers are planned for these systems, but their use raises some difficulties due to the extended nature of the beacons generated in the mesosphere and their spatiotemporal variability. We describe a performance analysis on the impact of laser launch telescope (LLT) location for the Thirty Meter Telescope (TMT) multiconjugate adaptive optics system. A semianalytical first-order noise propagation calculation is presented, supplemented by end-to-end Monte Carlo physical optics simulations. The principal conclusion of the study is that modestly superior performance is achieved with multiple LLT locations around the primary mirror, compared to a single central LLT behind the secondary mirror, but the largest value of any of these improvements is of the order of 20 nm rms for the expected wavefront sensor noise levels, suggesting that the final choice of geometry should depend primarily on the cost and complexity of implementation trade-off. This conclusion is also fully supported by the fact that, for the TMT 70 arcsec laser guide star (LGS) asterism, the fratricide effect reduces the performance of the central launch geometry by only a small amount. The reduction ranges from only a few nm rms at zenith to a few tens of nm at a 45° zenith angle in the worst case that the effect cannot be calibrated.

Simulation of ECCD optimization for neoclassical tearing mode suppression in KSTAR

In high confinement discharges of KSTAR, onset of neoclassical tearing modes (NTMs) by helically perturbed local bootstrap current will be inevitable and significantly degrade plasma confinement. For the suppression of NTMs in KSTAR, high power, long pulse 170 GHz electron cyclotron current drive (ECCD) system will be implemented to compensate the missing bootstrap current. A ray tracing analysis using TORAY-GA is performed to optimize the location of EC wave launch and to predict the performance of the current drive. From the optimization simulation, it is found that the launch location should be at − 30 cm below the midplane to maximize the profile figure of merit which enables more efficient NTM suppression in itself. The profile figure of merits on q = 3 / 2 and 2/1 resonant surfaces are estimated to be about 13.5 MA/rho 2 and 14.0 MA/rho 2, respectively, in the case of optimal profiles with 1 MW ECCD unit power. The 110 GHz ECCD as an alternative method with higher current drive efficiency shows larger driven currents than 170 GHz ECCD, but the profile figure of merit is not much improved due to its broader profile.

Boost-Phase Identification of Theater Ballistic Missiles Using Radar Measurements

This paper addresses the problem of identification of theater ballistic missiles during boost phase using radar measurements. Based on the use of the Wald sequential probability ratio test (SPRT), three identification algorithms are presented, corresponding to scenarios of increasing uncertainty. The use of the SPRT allows meeting specified false-alarm and missed-detection probabilities, while minimizing identification time. When the missiles' dynamic models and launch initial conditions (location and time) are completely and accurately known, the SPRT works directly with the raw radar measurements. In other scenarios, including a case where the launch location and launch time are unknown, two extended Kalman filters are used to generate the innovations sequences driving the SPRT. An extensive Monte Carlo simulation study is used to demonstrate the performance of the proposed procedures. Although the identification times and actual error probabilities depend, to some degree, on proper filter tuning, it is shown that reasonable mean identification times can be attained, corresponding to acceptable false-alarm and missed-detection rates, even in the presence of model uncertainties. This performance renders the proposed algorithms viable for the difficult problem considered.

Launch Detection Satellite System Engineering Error Analysis

Abstract : An orbiting detector of infrared (IR) energy may be used to detect the rocket plumes generated by ballistic missiles during the powered segment of their trajectory. By measuring angular directions of the detections over several observations, the trajectory properties, launch location, and impact area may be estimated using a nonlinear least-squares iteration procedure. observations from two or more sensors may be combined to form stereoscopic lines of sight (LOS), increasing the accuracy of the estimation algorithm. The focus of this research has been to develop a computer-model of an estimation algorithm, and determine what parameter, or combination of parameters will significantly affect on the error of the tactical parameter estimation. This model is coded in MATLAB, and generates observation data, and produces an estimate for time, position, and heading at launch, at burnout, and calculates an impact time and position. The effects of time errors, LOS measurement errors, and satellite position errors upon the estimation accuracy were then determined using analytical and Monte Carlo simulation techniques.

Erosion and Ejecta Reaccretion on 243 Ida and Its Moon

Galileo images of Asteroid 243 Ida and its satellite Dactyl show surfaces which are dominantly shaped by impact cratering. A number of observations suggest that ejecta from hypervelocity impacts on Ida can be distributed far and wide across the Ida system, following trajectories substantially affected by the low gravity, nonspherical shape, and rapid rotation of the asteroid. We explore the processes of reaccretion and escape of ejecta on Ida and Dactyl using three-dimensional numerical simulations which allow us to compare the theoretical effects of orbital dynamics with observations of surface morphology.The effects of rotation, launch location, and initial launch speed are first examined for the case of an ideal triaxial ellipsoid with Ida's approximate shape and density. Ejecta launched at low speeds (V⪡Vesc) reimpact near the source craters, forming well-defined ejecta blankets which are asymmetric in morphology between leading and trailing rotational surfaces. The net effect of cratering at low ejecta launch velocities is to produce a thick regolith which is evenly distributed across the surface of the asteroid. In contrast, no clearly defined ejecta blankets are formed when ejecta is launched at higher initial velocities (V∼Vesc). Most of the ejecta escapes, while that which is retained is preferentially derived from the rotational trailing surfaces. These particles spend a significant time in temporary orbit around the asteroid, in comparison to the asteroid's rotation period, and tend to be swept up onto rotational leading surfaces upon reimpact. The net effect of impact cratering with high ejecta launch velocities is to produce a thinner and less uniform soil cover, with concentrations on the asteroids' rotational leading surfaces.Using a realistic model for the shape of Ida (P. Thomas, J.Veverka, B. Carcich, M. J. S. Belton, R. Sullivan, and M. Davies 1996,Icarus120, 000–000), we find that an extensive color/albedo unit which dominates the northern and western hemispheres of the asteroid can be explained as the result of reaccretion of impact ejecta from the large and evidently recent crater “Azzurra.” Initial ejection speeds required to match the color observations are on the order of a few meters per second, consistent with models (e.g., M. C. Nolan, E. Asphaug, H. J. Melosh, and R. Greenberg 1996,Icarus, submitted; E. Asphaug, J. Moore, D. Morrison, W. Benz, and R. Sullivan 1996,Icarus120, 158–184) that multikilometer craters on Ida form in the gravity-dominated regime and are net producers of locally retained regolith. Azzurra ejecta launched in the direction of rotation at speeds near 10 m/sec are lofted over the asteroid and swept up onto the rotational leading surface on the opposite side. The landing locations of these particles closely match the distribution of large ejecta blocks observed in high resolution images of Ida (P. Lee, J. Veverka, P. Thomas, P. Helfstein, M. J. S. Belton, C. Chapman, R. Greeley, R. Pappalardo, R. Sullivan, and J. W. Head 1996,Icarus120, 87–105).Ida's shape and rotation allow escape of ejecta launched at speeds far below the escape velocity of a nonrotating sphere of Ida's volume and presumed density. While little ejecta from Ida is captured by Dactyl, about half of the mass ejected from Dactyl at speeds of up to 20 m/sec eventually falls on Ida. Particles launched at speeds just barely exceeding Dactyl's escape velocity can enter relatively long-term orbit around Ida, but few are ultimately reaccreted by the satellite. Because of its low gravity, erosion of Dactyl would take place on exceedingly short time scales if unconsolidated materials compose the satellite and crater formation is in the gravity regime. If Dactyl is a solid rock, then its shape has evolved from a presumably irregular initial fragment to its present remarkably rounded figure by collision with a population of impactors too small to be detected by counting visible craters. As the smallest solar system object yet imaged by a spacecraft, the morphology of Dactyl is an important clue to the asteroid population at the smallest sizes.

Space-based tactical ballistic missile launch parameter estimation

The author explores the influence of a priori uncertainties in launch time and trajectory fly-out profiles, along with sensor angle measurement errors, on the estimation of missile launch location and heading angle. An error model is developed to compute the statistics of the estimation errors using a single pair of angle measurements, one from each of two satellites, or both from the same satellite platform. The measurements and estimation methods are described, followed by a derivation of the estimation errors for the hypothetical case of perfect knowledge of trajectory and launch time. Using the ideal case as a framework, the errors are generalized to include trajectory and launch time uncertainties. The results are discussed with the aid of graphics which were run parametrically to highlight important dependencies and sensitivities.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>