摘要:

AbstractEarlyTRIESTE IandII* navigation problems, equipments, and results will be discussed for background information because our nation had no other operating manned deep submergence vehicle until 1965.** Search operations for the lost submarine THRESHER in 1963 and 1964 highlighted the necessity for navigational accuracy on the bottom of the ocean. Pioneer procedures, prototype equipment and instrumentation created a foundation for some modern and possibly future applications.

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00014.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00015.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractAtomic clocks did reacha perfection during the last years that it becomes likely to have position fixing by such clocks in the near future. Theoretically this was proposed sometimes in the past decades.Now we have two systems used for navigational purposes, the McDonnell Collision Avoidance System, well known to air navigation experts, using crystal clocks, and a geophysical surveying system, ANA,* developed by the “Gesellschaft für praktische Lagerstättenforschung”, Hannover, using Rubidium atomic clocks. Two ground stations are equipped with such clocks, a third is installed in an aircraft for time comparison with the ground‐based clocks. The difficulty to use the mentioned systems over longer periods as it would be necessary for maritime use, consists in the synchronization. There exist some proposals, till now not realistic and rather complicated, which would render possible to extend both methods to a general use for aircraft and ships. The further development of atomic clocks seems to be very pr

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00016.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractThe vessel characteristicsof ocean shipping‐have undergone rapid change in recent years. Panama Canal traffic has also been subject to a substantial growth in number and size of transit. These factors, together with the restrictive size of the existing canal, have provided need to consider modernization of the canal or replacement by a sea‐level canal.In 1965, President Johnson appointed a five‐man commission, designated as the Atlantic‐Pacific Interoceanic Canal Study Commission, to investigate the possibility of the construction of a sea‐level canal. An important area of this investigation is the establishment of economical and safe channel criteria. The trend to increase the size of ships with equal or somewhat less maneuverability complicates the problem. This paper presents results of studies to optimize design operation criteria, considering the maneuverability of ships which are anticipated to use the new facility during its useful life, say between the years 1990

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00017.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00018.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractError equations are derivedfor a self‐contained aircraft navigation system comprised of (a) a Janus‐mixed doppler radar ground velocity sensor (b) a three‐axis gyroscopic reference platform, used as an artificial horizon and untorqued directional gyro, and (c) a computer. Except for dynamic inaccuracies in the indication of the local vertical, the navigation system is dynamically exact. Propagation of error is dependent on aircraft velocity and latitude, and for northerly flight (in the northern hemisphere) the system becomes unstable. However, for flights of short duration and/or at low speeds the system remains u

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00019.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractAsignificantly improved conceptand technique of sonar ranging has been developed by the Deep Tow group of the Marine Physical Laboratory. This OFFSET technique resolves the multiple sweep ambiguity encountered in precision sonar ranging with graphic recorders by the temporary use of a small relative change of sweep rate. Using the OFFSET technique, high resolution and precision are maintained during the gross range measurement. These are obtained and displayed permanently with one recorder. Compared with conventional methods and their limitations, the advantages of OFFSET, as well as its simplicity of operation, make it a worthwhile, easily implemented extension of the graphic recorder. Echo sounding and acoustic transponder data taken at sea substantiate the usefulness and applicability of the OFFSET method to echo sounding and acoustic navigation problems.

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00020.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractSince july1968, oceanographers aboard USNS CHARLES H. DAVIS (T‐AGOR 5) have been utilizing Navy TRANSIT satellites and the ITTFL 4007AB satellite receiver with a PDP‐8/S general purpose computer to acquire position data at sea. The system has been operated without a specially trained technician, and with a high degree of reliability. The authors, with no formal background, and only modest practical experience in computer technology and electronics, have been able to acquire excellent navigational data to support their scientific progr

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00021.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractNavigation and mapping techniquesdeveloped for surface ships are not optimum for accurate sub‐surface navigation of submersible vehicles. The long‐range acoustic transponder techniques which have been developed for use by towed vehicles in deep water are also not suitable for use in relatively shallow depths (200 fathoms or less). For these reasons, the Marine Physical Laboratory has undertaken a series of experiments to develop techniques using equipment compatible with that which could be installed on submersible vehicles having limited payload capability. These techniques allow the use of side‐looking sonar to map a patch of sea floor (about 5 sq mi) without reliance on surface‐acquired information, and with confidence that there is continuous coverage of the area. Mapping techniques can be selected to cope with the two extreme cases of a continuous distribution of targets, and an essential absence of

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00022.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractTrilateration computationsof radar measurements made between surface ship‐based interrogator‐responsors and shore‐based transponders can be used to obtain better than two‐foot positional accuracy at line‐of‐sight ranges of the order of five miles. Use of nanosecond pulses provides elimination of the usual range errors caused by multipath reflections from sea surface and ship's superstructure. A description of currently available hardware to accomplish these positional accuracies i

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1970.tb00023.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY