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1.
This paper is the complete text of an address given at the IEEE meeting in New York on March 23, 1966, in ?Undersea Technology Session,? covering the U. S. Navy's furtherance of the development of Ocean Engineering and some plans for the future. The items covered include the deep submergence systems project, SEALAB III, salvage work packages circa 1967, and additions to the Marine Engineering Laboratory.  相似文献   

2.
This review assumes that many non-US readers may not be well-informed about the steps and work in radar development in the US after WW II to the present. Many know MIT by name and recall the famous Radiation Laboratory Series. But the more recent technical history has been less in the "public domain." In an attempt to correct this, one of the key institutions in the field, the MIT Lincoln Laboratory two years ago produced a special issue of their regular publication. Although the document currently at hand is not a book in the strict sense, the size, shape, and editorial comprehensiveness of the MIT Lincoln Laboratory Journal's Fifty-Year Anniversary Issue (12, 2, 2000) justifies calling this article being treated as a book review.  相似文献   

3.
The purpose of this paper is to describe the needs of the U.S. Army for silent portable power sources, both in the near and longer term future. As a means of doing this, the programs of the Power Sources Division of the Army Research Laboratory are discussed. In carrying out these programs, the personnel of the Power Sources Division work closely with the Battery Management Office of the Army Materiel Command, which is located in the Logistics and Readiness Directorate of the Communication-Electronics Command (CECOM). We are also closely integrated with the Army Research Office, and the fuel cell personnel of the CECOM Research Development and Engineering Center (RDEC), and the battery personnel of the RDECs for the Tank and Automotive Command and the Missile Command. The six program areas discussed in which the Power Sources Division is engaged are: primary batteries, rechargeable batteries, reserve/fuze batteries, pulse batteries and capacitors, fuel cells, and thermophotovoltaic power generation  相似文献   

4.
The commenter points out that a direct Global Positioning System (GPS) algorithm together with discussions on the existence and uniqueness of the solution appeared in his paper (J. Guidance, Control, and Dynamics, vol.9, p.715-17, Nov./Dec. 1986). Since the GPS solution is reduced to solving a quadratic equation, the existence and uniqueness can be easily tested. J.S. Abel and J.W. Chaffee, in the above-titled paper (ibid., vol.26, no.6, p.748-53, Sept. 1990), show that the GPS solution problem is similar to the hyperbolic-fix problem. The commenter notes that it can be inferred from his later work (ibid., vol.26. no.5, p.748-53, Sept. 1990) that the two solutions exist if and only if the four GPS satellites are coplanar, in which case the two solutions are mirror-symmetric with respect to the GPS plane  相似文献   

5.
Single stage Stirling coolers providing refrigeration at around 80 K have been developed for space use and are now being produced commercially. Development work is now concentrating on multistage coolers for temperatures below 30 K. This paper describes results from a two stage cooler built at the Rutherford Appleton Laboratory and preliminary tests on a closed cycle 4 K cooler.  相似文献   

6.
Junocam is a wide-angle camera designed to capture the unique polar perspective of Jupiter offered by Juno’s polar orbit. Junocam’s four-color images include the best spatial resolution ever acquired of Jupiter’s cloudtops. Junocam will look for convective clouds and lightning in thunderstorms and derive the heights of the clouds. Junocam will support Juno’s radiometer experiment by identifying any unusual atmospheric conditions such as hotspots. Junocam is on the spacecraft explicitly to reach out to the public and share the excitement of space exploration. The public is an essential part of our virtual team: amateur astronomers will supply ground-based images for use in planning, the public will weigh in on which images to acquire, and the amateur image processing community will help process the data.  相似文献   

7.
The commenters object to criticisms of their work that appeared in the above-titled paper (ibid., vol.25, no.5, p.590-601, Sept. 1989) and provide a defense of their results. The author presents further arguments to buttress his claims  相似文献   

8.
The author reminisces about the early days of radio. He describes the first radio sets and his entry into commercial radio in the 1920s. He discusses his work at GE, RCA, and Brunswich Balke Collender during the 1920s and military research he as involved in during the 1930s  相似文献   

9.
The Laser Communications Laboratory (LCL) of the Wright Laboratory Avionics Directorate is heavily involved in designing optical communications systems covering the full optical spectrum to meet our current and future military communications requirements. This paper summarizes the in-house designed and built solar blind ultraviolet communications system used in the LCL to investigate non-line-of-sight data and voice links. It also summarizes some of the previous DoD work accomplished to exploit free space communications via ultraviolet radiation. In addition, safety factors peculiar to ultraviolet radiation in a closed cockpit environment are addressed. An evaluation of the current electrodeless ultraviolet communications system and a synopsis of planned future projects to improve the system are included in the paper  相似文献   

10.
The extraordinary life and scientific achievements of Johannes Geiss span an almost impossible breadth of scientific topics, from the study of rocks to tenuous plasmas, from volcanoes to meteorites. But, his impact also extends way beyond the field of science. Professor Geiss is a well-known teacher and a highly successful science leader whose impact has been felt at the University of Bern, in Switzerland, and around the globe. We present here a brief summary of this highly successful career via a pictorial overview and a movie compiled by a former student who had the good luck to work with Professor Geiss during his years at the University of Bern. Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   

11.
柔韧性在运动中具有重要意义,它是有效改进技术的必要基础,也是保证提高运动技术水平的基本因素之一。针对大学生在常规的业余训练中加大柔韧性的练习,能有效提高体能训练的质量,从而达到训练目的,提高运动成绩。  相似文献   

12.
The mission goal of the 2009 Mars Science Laboratory is to assess the habitability of a region on Mars. This large rover incorporates an Analytical Laboratory that contributes to this mission objective by means of a detailed characterization of mineralogy and chemistry. The Sample Analysis at Mars instrument suite in the Analytical Laboratory provides the capability to analyze volatiles released from rocks and soils and gases directly sample from the atmosphere. A primary focus of this suite is the detection and identification of organic molecules. The protocols for the extraction and analysis of organics under development for this mission are described as are experiments carried out on Mars analog samples to evaluate these methods.  相似文献   

13.
The author takes a look at the very early days of the MIT Instruments Laboratory and its successor, the MIT Instrumentation Laboratory. The discussion ranges over some of the incidents and events as these early instrument developers groped with problems that others had already failed to solve, and for which current solutions were declared adequate  相似文献   

14.
15.
The goal of this research is to explore and prevent robust concepts for telerobotic support of space servicing, assembly, maintenance, and telescience tasks. This goal is being addressed through a program of coordinated work in artificial intelligence, robotics, and human factors. The general research objective is the fusion of robot sensing and manipulation, teleoperation, and human and machine cognitive skills into an effective architecture for supervised task automation. NASA is evaluating results of this research program in a ground laboratory telerobot testbed under development at the Jet Propulsion Laboratory. The testbed development activity includes integrated technology demonstrations. The demonstrations show telerobot capabilities to perform tasks of increasing complexity, and duration in increasingly unstructured environments. The first such demonstration is the ground-based grappling, docking, and servicing of a satellite taskboard. The author outlines this demonstration and briefly reports on some aspects of its implementation  相似文献   

16.
Many measurements of ionospheric temperature have been made during the last decade and have shown a considerable departure from thermal equilibrium there. Theoretical work has led to a general understanding of the processes which determine the energy balance of the charged particles, and most features of the experimental results are well understood in the F-region. The position in the E-region where different methods of measurement, known to agree fairly well at greater heights, appear to disagree is less clear, whilst in the D-region no direct observations of charged particle temperature exist. The theoretical expectation here is that, on account of the rapid exchange of energy amongst the particles by collisional processes, temperature equality will prevail.This review is based on material published up to January, 1970.On leave of absence from Mullard Space Science Laboratory, University College London.  相似文献   

17.
The theory and the design of propellers of minimum induced loss is treated. The pioneer analysis of this problem was presented more than half a century ago by Theodorsen, but obscurities in his treatment and inaccuracies and limited coverage in his tables of the Goldstein circulation function for helicoidal vortex sheets have not been remedied until the present work which clarifies and extends his work. The inverse problem, the prediction of the performance of a given propeller of arbitrary form, is also treated. The theory of propellers of minimum energy loss is dependent on considerations of a regular helicoidal trailing vortex sheet; consequently, a more detailed discussion of the dynamics of vortex sheets and the consequences of their instability and roll up is presented than is usually found in treatments of propeller aerodynamics. Complete and accurate tables of the circulation function are presented. Interference effects between a fuselage or a nacelle and the propeller are considered. The regimes of propeller, vortex ring, and windmill operation are characterized.  相似文献   

18.
Senator Glenn is interviewed about his experiences on Friendship 7 and the Shuttle Discovery, expectations of early astronauts, lunar missions, the International Space Station, international dimensions of space activities, public confidence in NASA, attracting young people to the aerospace industry, highlights of his career, and the future of flight.  相似文献   

19.
A major technology barrier to the application of pulse compression for the meteorological functions required by a next generation ATC radar is range/time sidelobes which mask and corrupt observations of weak phenomena occurring near areas of strong extended meteorological scatterers. Techniques for suppressing range sidelobes are well known but without prior knowledge of the scattering medium's velocity distribution their performance degrades rapidly in the presence of Doppler. Recent investigations have presented a “doppler tolerant” range sidelobe suppression technique. The thrust of the work described herein is the extension of previous simulations to actual transmitted dispersed/coded waveforms using the S-band surveillance radar located at Rome Laboratory Surveillance Facility. The objectives of the experiment are: 1) to extend the verification of the simulation of the Doppler tolerant technique; and 2) to demonstrate that the radar transmitter, waveform generator, and receiver imperfections do not significantly degrade resolution, performance or reliability of meteorological spectral moment estimates  相似文献   

20.
目前这本书是我在山东教育台十四集电视节目《道本管理——让心灵回家》的文字版,比起音像版来,这个文字版又增加和补充了一些全新的内容。这本书的主题和内容是我自1983年学习西方管理开始,经历了近三十年的实践、研究、学习和思考的历程之后的心得,是在对西方管理的崇尚和实践遭遇瓶颈之后的一次对管理思想和实践的突破,是对许多企业管理问题的重新思考与定位。上个世纪九十年代,在熟悉使用西方的管理方法之后,在实践中为了解决企业中的问题,更是把这套管理模式中的制度化、标准化、程序化做到了极致,以为管理中所有的问题都可以被囊括,都  相似文献   

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