Deep space exploration

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Overview of the Overall Technical Research of the Deep Space Exploration Antenna Array

Overview of the Overall Technical Research of the Deep Space Exploration Antenna Array

At present, the telemetry and communication tasks of deep space exploration are carried out by single large diameter antennas. As the antenna size increasing, its request of the mechanical structure, servo control, etc. are also to rise. The difficulty of the engineering design, processing and measuring technology is close to or reach the technical limit. In the process of antenna usage, the maintenance cost of the system will also increase exponentially. Therefore, it is very difficult to improve the antenna system performance by increasing the antenna aperture and to realize the task demand. As the bottleneck in the development of traditional large-aperture antenna technology, antenna array technology came into being as a new concept and technology, which greatly enhanced the future deep space exploration communications system through the formation of multiple small and medium-sized antennas ability. It will provide duplex communication capability and two-way ranging capabilities after the launch of the spacecraft, or at the point of intersection, and may be reconfigured to meet mission requirements during spacecraft flight to alleviate and resolve the ever-increasing antenna aperture System performance difficulties. Therefore, the antenna array technology will be a new and feasible solution to the problem of deep space exploration, which has traditionally been one of the new effective technological ways to pass the system detection capability and technical performance by continuously increasing the antenna aperture.
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The Design and Simulation Analysis of K Band Large Reflector Antenna System for Deep Space Exploration

The Design and Simulation Analysis of K Band Large Reflector Antenna System for Deep Space Exploration

Deep space communication is the communication between the communication entity on the earth and the aircraft leaving the earth satellite orbit into the solar system, the distance can reach hundreds of kilometers or thousands of kilometers, or even 100 million kilo- meters. Our country’s aerospace technology has been continuously making great advancement since the founding of People’s Republic of China from the ini- tial Dong Fang Hong earth orbiting satellite to the latest Tiangong-1 manned spacecraft, as well as the to-be-implemented deep space exploration for Mars. Its long distance (magnitude of 100 million kilometers) deep space exploration proposes higher requirements for the wireless communication between ground and deep space explorer: The antenna system should bear the features of high gain, high sensitivity and high bit rate [1] , for which purpose, radio frequency antenna or optical communication antenna could be used. Be- cause of the immaturity of current optical communica- tion technology for long distance purpose and rela- tively simple reflector shape, large reflector antenna is commonly used in deep space exploration ground stations home and abroad. There are many different reflector antennas of single-reflector, dual-reflectors and array-reflectors consisting of some smaller reflec-
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Does the worsening galactic cosmic radiation environment observed by CRaTER preclude future manned deep space exploration?

Does the worsening galactic cosmic radiation environment observed by CRaTER preclude future manned deep space exploration?

Ionizing radiation from galactic cosmic rays (GCRs) and solar energetic particles (SEPs) remains a significant challenge to long-duration crewed missions to deep space. Human beings face a variety of consequences ranging from acute effects (radiation sickness) to long-term effects including cancer induction [cf. NRC, 2008] and damage to organs including the heart and brain. The risk is a function of the effective dose, which is related both to energy per unit mass (expressed in Gy = J/kg) absorbed by tissue organs, and the biologi- cal effectiveness of the radiation. In this paper, we use recent measurements from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) [Spence et al., 2010] zenith-facing D1/D2 detectors to determine dose and dose equivalent rates (http://prediccs.sr.unh.edu/craterweb) on the Lunar Reconnaissance Orbiter (LRO). We also utilize measurements from the CRIS instrument [Stone et al., 1998] aboard the ACE space- craft to accurately quantify the levels of radiation exposure. We assume representative areal densities of 0.3 g/cm 2 , 10 g/cm 2 aluminum (Al), and 20 g/cm 2 shielding, corresponding to thin, intermediate, and
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Design Space Exploration for a Custom VLIW Architecture

Design Space Exploration for a Custom VLIW Architecture

The VEX C compiler is a derivation of the Lx/ST200 C compiler, itself a descendant of the Multiflow C compiler. It is a robust, ISO/C89 compiler that uses trace scheduling as its global scheduling engine. A very flexible programmable machine model determines the target architecture. For VEX, we selectively expose some of the parameters to allow architecture exploration by changing the number of clusters, execution units, issue width, and operation latencies without having to recompile the compiler. Hewlett-Packard Laboratories provide a toolchain [7] with the compiler.
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Towards Design Space Exploration for Biological Systems

Towards Design Space Exploration for Biological Systems

difficulty in engineering the cell to be more efficient when performing more elaborate tasks. This is where structured frameworks such as used in methods for design space exploration would come in useful. Whereas biological problems are traditionally tackled with a reverse engineer- ing approach, much can be said to, as an alternative, use a forward engineering approach such as used in design space exploration for computer systems engineering (Fig- ure 1). These methods are capable of evaluating design options quickly and formally on a larger (systems-) scale. We anticipate that methods from the domain of computer systems engineering may as such serve as an alterna- tive framework to formally evaluate design of biological systems [9], [16]. In this way, general principles that govern the structure and behavior of cellular systems may be discovered [9]. The application of methods for design space exploration to biological systems has not been attempted before. As proof-of-principle, we simulate a biological process to exemplify the use and benefit of such methods for biology. We take our ideas from the domain of computer systems engineering, with a special interest in embedded computer systems.
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The psychasthenia of deep space: evaluating the ‘reassertion of space in critical social theory’

The psychasthenia of deep space: evaluating the ‘reassertion of space in critical social theory’

Gibson himself describes Neuromancer as “a way of trying to come to terms with the awe and terror inspired in me by the world in which we live” [Gibson, quoted in Kellner, 1995]. We have charted this duality between ‘awe’ and ‘terror’ from the nineteenth century literature examined in the previous part (4.2) through the ‘modern’ literary responses to the city of contemporary authors. However, recently this duality has become more blurred as what Prendergast terms narratives of “end-time” (the dystopian view of imminent disaster) and of “playtime” (the jouissance or thrill of the urban) have moulded into one [Prendergast, 1992; p 207]. While affirming that “if apocalyptic imaginings and ludic fantasies have acquired pride of place among our postmodern urban shibboleths, they are less novel than we might think”, I would reject the continued distinction that Prendergast draws between these two narratives in the contemporary context in which “the fixative [of the collage-city is] no longer holding, as life speeds up more and more” [ibid.]. Rather, the two narratives of end-time and playtime, paralleled in Koolhaas’ reference to the theatres of the beginning and end of the world on Coney Island [see above p 58], have become fused, mirroring the duality of Nietzsche’s ‘rausch’. We see this transition in the move from the clean aspirational styling of Kubrick’s 2001: A Space Odyssey to “the more grimy, post-urban realism of Batman, Neuromancer and Bladerunner” [Rushkoff, 1994; p 17], in the apocalyptic arousal of Ballard’s Crash and Cocaine Nights [Ballard, 1995 and 1996] and in Fielder’s question, “Do those who imagine the end of the city, whether in fire or ice, wish it or dread it - or, like me, dread they wish it, wish they dreaded it?” [Fielder, 1981; p 120].
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The psychasthenia of deep space: evaluating the 'reassertion of space in critical social history'

The psychasthenia of deep space: evaluating the 'reassertion of space in critical social history'

might in fact form the basis for the reassertion of [material] space in critical social theory.. Finally, Tuan's confessional statement serves to introduce the importance of m[r]

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An Exploration of Word Embedding Initialization in Deep Learning Tasks

An Exploration of Word Embedding Initialization in Deep Learning Tasks

Word embeddings are the interface be- tween the world of discrete units of text processing and the continuous, differen- tiable world of neural networks. In this work, we examine various random and pretrained initialization methods for em- beddings used in deep networks and their effect on the performance on four NLP tasks with both recurrent and convolu- tional architectures. We confirm that pre- trained embeddings are a little better than random initialization, especially consider- ing the speed of learning. On the other hand, we do not see any significant dif- ference between various methods of ran- dom initialization, as long as the variance is kept reasonably low. High-variance ini- tialization prevents the network to use the space of embeddings and forces it to use other free parameters to accomplish the task. We support this hypothesis by ob- serving the performance in learning lexical relations and by the fact that the network can learn to perform reasonably in its task even with fixed random embeddings. 1 Introduction
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Space Exploration and Education using Virtual Reality

Space Exploration and Education using Virtual Reality

Neha Kenche, Abhishek Moghe, Tapan Auti, Kevin Dass, Geeta S. Navale, "Space Exploration and Education using Virtual Reality", International Journal of Scientific Research in Computer Science, Engineering and Information Technology (IJSRCSEIT), ISSN : 2456-3307, Volume 5 Issue 3, pp. 121-126, May-June 2019. Available at doi : https://doi.org/10.32628/CSEIT195348

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Nuclear Power Sources and Future Space Exploration

Nuclear Power Sources and Future Space Exploration

After the international legal regime, the United States's domestic regulatory and procedural structure is examined, with a discussion of an illustrative case in which [r]

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Support Vector Machines for Design Space Exploration

Support Vector Machines for Design Space Exploration

In the left diagram of Fig. 7 the result of the design space exploration after about 40 measurements is depicted. The approximated design space is a good representation of the actual one. It can be seen that the algorithm places the points closely around the design space border and only sparsely inside the design space, which constitutes an economical use of the available measurements. The reverse, and not desirable, behavior can be seen in the right diagram where a different candidate point placement strategy was used: the candidates were always placed at the inside of the current boundary. The center diagram shows the first step of this exploration run as an example.
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A Systematic Exploration of the Feature Space for Relation Extraction

A Systematic Exploration of the Feature Space for Relation Extraction

posed and defined a unified graphic representation of features for relation extraction, which serves as a general framework for systematically exploring fea- tures defined on natural language sentences. With this framework, we explored three different repre- sentations of sentences—sequences, syntactic parse trees, and dependency trees—which lead to three feature subspaces. In each subspace, starting with the basic unit features, we systematically explored features of different levels of complexity. The stud- ied feature space includes not only most of the ef- fective features explored in previous work, but also some features that have not been considered before. Our experiment results showed that using a set of basic unit features from each feature subspace, we can achieve reasonably good performance. When the three subspaces are combined, the performance can improve only slightly, which suggests that the sequence, syntactic and dependency relations have much overlap for the task of relation extraction. We also found that adding more complex features may not improve the performance much, and may even hurt the performance. A combination of features of different levels of complexity and from different sentence representations, coupled with task-oriented feature pruning, gives the best performance.
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High level synthesis for design space exploration

High level synthesis for design space exploration

The paper explores design space exploration using HLS techniques to determine the trade-off of the performance parameters of the architecture obtained. Systolic array is considered as the basic hardware type and the mapping methods with and without transformations are applied to implement a compute intensive DSP application. Pipelining and unrolling are the HLS transformations considered here and the target hardware is Xilinx Zynq- zynq_fpv6 xc7z015clg485-2.

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Pathological Evidence Exploration in Deep Retinal Image Diagnosis

Pathological Evidence Exploration in Deep Retinal Image Diagnosis

the activated neurons that directly related to the prediction. To visually illustrate the extracted pathologic descriptor, we followed the similar methodology of Koch’s Postulates that aim to identify the unknown pathogen. In addition, we pro- posed a GAN based visualization method to visualize the pathological descriptor into a fully controllable pathology retinal image from an unseen binary vessel segmentation. The retinal images we generated have shown medical plau- sible symptoms as the reference image. Since pathological descriptor is associated with individual lesion and spatial in- dependent, we could arbitrarily manipulate the position and quantity of the symptom. We verified the generated images with a group of licensed ophthalmologists and our result is shown to be both qualitatively and quantitatively supe- rior to state-of-the-art. The feedback of doctors shows our strategy has strengthened their understanding on how deep learning makes prediction. Not limited in interpreting med- ical imaging, we will extend our strategy to more general interpretability problem.
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A Unified View of Core Selection and Application Steering in Heterogeneous Chip Multiprocessors.

A Unified View of Core Selection and Application Steering in Heterogeneous Chip Multiprocessors.

The core design space consists of design points created by varying the clock period and the complexity (structure sizes and pipeline widths) of different pipeline stages of a superscalar processor. The design space is spanned by the independent design parameters enumerated in Table 5.2. The depth of a canonical pipeline stage for a given design point is the degree of sub-pipelining required so that a given complexity of the pipeline stage may fit in a given clock period. A cartesian product of all parameter values gives 3.3 million design points. Not all of these design points are valid. Firstly, as we are using the FabScalar [13] canonical template, a pipeline stage cannot be made arbitrarily deep. Secondly, for a canonical pipeline stage, only those design points are considered that have the largest-sized structure for a given width, depth, and frequency of that canonical pipeline stage. This helps in pruning the design space and retaining good design points. By performing this design space pruning, we are able to restrict it to 13,966 design points.
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ESSC News 4

ESSC News 4

This acronym stands for “Towards Human Exploration of Space: a EUropean Strategy”, and is a proposal for an EC Coordination and Support Action to be developed within the Space theme of the Commission’s 7 th Framework programme. The proposal consortium is coordinated by ESF-ESSC and comprises 5 other institutional partners: CNRS- IPHC (Strasbourg), DLR (Köln), MEDES (Toulouse), SCK-CEN (Mol), and the University of Sheffield. The objective of THESEUS is to develop an integrated life sciences research roadmap enabling European human space exploration in synergy with the ESA strategy, taking advantage of the expertise available in Europe and identifying the potential of non space applications and dual research and development. This should be achieved by (a) identifying disciplinary research priorities; (b) focussing on fields with high terrestrial application potential; and (c) building a European network as the core of this strategy.
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Space Journey: Encouraging astronomy education and space exploration through an interactive experiential design installation of an astronaut training program

Space Journey: Encouraging astronomy education and space exploration through an interactive experiential design installation of an astronaut training program

Before going into space, astronauts must endure many hours of training and preparation in which they learn about space, science and technology. Encouraging astronomy education in younger generations has the potential to improve the skills, motivation and knowledge to train like an astronaut. This could positively impact the world by inspiring new scientists and amateurs to keep exploring and researching the universe and, through them, science and technology could inevitably evolve. This project presents different mind and body challenges that teach and entertain the users on how to train like an astronaut. By playing these challenges, the users gain different skills that are useful for astronauts in space. While playing, the users explore the wonders of the universe, learning not only about astronauts but space in general.
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STATISTICAL VERIFICATION OF PERFORMANCE OF GENETIC ALGORITHM IN SCHEDULING

STATISTICAL VERIFICATION OF PERFORMANCE OF GENETIC ALGORITHM IN SCHEDULING

(iii) Mutation: This operator involves alteration of a single chromosome randomly chosen against a chosen probability. It explores the solution space to find the chance variations. The probability is chosen as 0.1 as a higher value will lead to unstable population and delayed convergence. The mutation applied here inverts the sequence of jobs in a randomly chosen chromosome at a randomly chosen operation level. The occasional mutations insure that useful genes not present in the current population get a chance to enter the population pool [Faulkener and Bouffouix, (1991)].

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Gay neo tribes : an exploration of space and travel behaviour

Gay neo tribes : an exploration of space and travel behaviour

There were no road signs, nor bright, vivid, pleading resort billboards along the highway. And all-knowing Siri seemed to be lost as well, off the grid, up here in Far North Queensland. As I drove the tiniest rental car up and down Captain Cook Highway, just me and my bright red Hyundai, I had no way to find my destination other than the brief, cryptic text message I received from the resort manager: ‘3km past Rex Lookout look for a M30 road sign and after 50m turn right’. I felt like I was trying to find Platform 9¾, except I was lost on the beach. Worse, there was barely any phone signal – every traveller’s nightmare. As I learned later, my idyllic and remote destination relies on a satellite phone system, and – cut off from the ease of modernity’s ubiquitous, unceasing connectivity – I abruptly felt as if I was adrift in time, as well as space. At the end of a journey of almost eight hours from Hobart, Tasmania, I finally reached my destination: the one and only gay and lesbian resort in Australia. As I entered the reception area I was greeted with a warm salutation: ‘Welcome to the family, we’ve been waiting for you’. Although the tiny building housing the reception desk, and its welcoming occupant, sat right behind the main hotel building towering above it, this space felt distinctly like an inviting gateway to a truly idyllic resort life. As I walked through the reception, and entered the main resort area – the bar, the restaurant, the ocean! – I noticed this space was filled with friendly gay men, all seemingly enjoying perfect relaxation. It felt immediately as though they had known each other for a long time. I soon discovered I was wrong. How do they know each other? I wondered. How did they find this place? Why, of everywhere on Earth, did they travel here?
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Suspension of presence : an exploration of the interconnectedness of the body, space and time

Suspension of presence : an exploration of the interconnectedness of the body, space and time

Consequently, the basis for this investigation 1s the manufacture of "space" Following the idea that space 1s not restricted to being "empty" air, but can be filled or formed by substanc[r]

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