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101.
Douglas A. Vakoch 《Acta Astronautica》2011,68(3-4):451-458
Throughout the history of the Search for Extraterrestrial Intelligence (SETI), there has been widespread recognition of the profound societal implications of detecting intelligence beyond Earth. At the SETI Institute, interstellar message construction serves as the focus of a multidisciplinary attempt to prepare for the cultural impact of signal detection and the critical events that would follow. Interstellar message construction at the SETI Institute builds upon the recommendations of the 1991–1992 Workshops on the Cultural Aspects of SETI, while also exploring opportunities for multidisciplinary contributions on new topics. Through a series of international workshops in Toulouse, Paris, Zagreb, Washington, and Bremen, the SETI Institute and partner organizations have fostered broad-based discussion about some of the most important decisions that would follow detection of extraterrestrial intelligence, including “should we reply?” and if so, “what should we say, and how might we say it?”. Several of the themes addressed at these workshops will be highlighted, including the relationship between art and science in designing messages, the value of interactive messages, and the importance of better understanding the nature of language. 相似文献
102.
Douglas A. Vakoch 《Acta Astronautica》2011,68(3-4):476-488
The Search for Extraterrestrial Intelligence (SETI) typically presupposes contact with extraterrestrial civilizations much longer lived than humanity. Many have argued that given humanity's “youth,” the burden of transmitting should be placed on the extraterrestrial civilizations, which presumably possess more advanced technologies. These assumptions have contributed to the current emphasis on Passive SETI. Complementing this existing stress on Passive SETI with an additional commitment to Active SETI, in which humankind transmits messages to other civilizations, would have several advantages, including (1) addressing the reality that regardless of whether older civilizations should be transmitting, they may not be transmitting; (2) placing the burden of decoding and interpreting messages on advanced extraterrestrials, which may facilitate mutual comprehension; and (3) signaling a move toward an intergenerational model of science with a long-term vision for benefiting other civilizations as well as future generations of humans. Technological requirements for Active SETI are considered, and a case is made for Active SETI as a means for experimentally testing variants of the Zoo Hypothesis. Recommendations are provided for sustaining Passive and Active SETI and the communities that conduct these searches. 相似文献
103.
104.
A Dialogic Model of constructing a unified reply message is suggested in which differences between perspectives are valued, rather than minimized. In this model, a diversity of views is seen as a virtue. Consensus in the broad sense of agreeing to include multiple perspectives is encouraged, while consensus in the narrow sense of everyone agreeing about all parts of the message is seen as overly restrictive, if not impossible. In the Dialogic Model, even perspectives that are irreconcilable with one another might be included in a single reply. Drawing upon multiple perspectives allows us to expand beyond our own preconceptions, gives extraterrestrials several ways to understand our views of the world, and portrays the breadth of human concerns.Seven benefits of beginning work on a reply message immediately are identified: (1) concretely understanding the challenge of creating an adequate reply; (2) helping decode messages from extraterrestrials; (3) creating interstellar compositions as a new form of art; (4) having a reply ready in case we receive a message; (5) providing a sense of concrete accomplishment; (6) preparing for an active search strategy; and (7) gaining public support for SETI. 相似文献
105.
In this paper we revisit the topic of how to formulate error terms for estimation problems that involve rotational state variables. We present a first-principles linearization approach that yields multiplicative error terms for unit-length quaternion representations of rotations, as well as for canonical rotation matrices. Quaternion algebra is employed throughout our derivations. We show the utility of our approach through two examples: (i) linearizing a sun sensor measurement error term, and (ii) weighted-least-squares point-cloud alignment. 相似文献
106.
James A. Abrahamson 《Space Policy》1985,1(2):118-121
This article outlines the objectives of the Strategic Defense Initiative (SDI) Program and describes the new technologies being considered by the Program. The author puts forward the view that the SDI will yield great benefits beyond the military goals, in terms of important technological advances, stimulation of the US economy and increased national security. 相似文献
107.
Boerner Wolfgang-M. Cole James B. Goddard William R. Tarnawecky Michael Z. Shafai Lotfallah Hall Donald H. 《Space Science Reviews》1983,36(2):195-205
A sensitive search for pulsars inside a sample of gamma-ray source error boxes has been carried out using the Arecibo and Parkes radiotelescopes. The paper describes the motivation of this search and the characteristics of the experiments used. As a preliminary result, new pulsars have been discovered and some of them are possibly candidates to be the counterparts of the gamma-ray sources. 相似文献
108.
Microwave Landing System Area Navigation 总被引:1,自引:0,他引:1
The International Civil Aviation Organization (ICAO) Standards and Recommended Practices (SARPS) states that the Time Reference Scanning Beam (TRSB) Microwave Landing System will supplant the existing Instrument Landing System (ILS) as the recognized international standard as early as 1995. The MLS provides the ability to determine the aircraft's position in three dimensional space over a large coverage volume in the airport terminal area. This affords the capability to navigate and execute approaches throughout this volume of coverage. This technique is known as Microwave Landing System Area Navigation (MLS RNAV). In order to assess and further develop the potential capabilities of MLS RNAV, the FAA Technical Center has undertaken the tasks of performing analytical studies, as well as the development of a prototype MLS RNAV system. 相似文献
109.
James J. Rotter 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(11):163-167
The use of large plastic balloons as a research tool has increased dramatically since the developmental work of the early 1950's. The continuing demand by the scientific community for higher float altitudes, heavier payloads, and longer flight durations has severely challenged current design and analysis procedures. Previous simplifying assumptions concerning the balloon shape and stress must be reassessed in order to develop better analytical design and stress analysis procedures. A brief history of balloon stress analysis procedures and accompanying assumptions are presented. The limitations of old methods and recent improvements by Smalley, Alexander, Rand, and others are examined and compared. Finite difference and finite element techniques offer promise for more accuracy with fewer over-simplifying assumptions. Available methods are examined for potential use in various stress analysis requirements. 相似文献
110.
Maurer RH Roth DR Kinnison JD Goldsten JO Gold RE Fainchtein R 《Acta Astronautica》2003,52(2-6):405-410
We describe the instrument design and detector development for MANES which has been selected to fly on the Mars 2003 Lander. Section 1 explains the need for the spectrometer in determining the increased risk of carcinogenesis for astronauts. Section 2 presents the instrument design including an outline drawing, a cross-sectional view and a detailed block diagram. Sections 3 and 4 describe the low and high energy detector components of the spectrometer and present responses to monoenergetic neutron beams. Sections 5 and 6 explain the design approaches to charged particle discrimination and instrument transfer function modeling. 相似文献