摘要:

Isostatic reductions for gravity stations can be made with the aid of punched‐card methods. A discussion of the precision that is needed and of the results that can be obtained is included. The method may be applied to a large volume of data with a saving in time and cos

ISSN:0002-8606    

DOI:10.1029/TR028i006p00823

年代:1947

数据来源: WILEY

摘要:

This paper describes how the equivalent of a least‐squares adjustment of a level or traverse net may be obtained by electrical measurements in an analogous electrical net. The lengths of the survey lines are replaced by proportional electrical resistances; the survey closures are replaced by proportional small dc voltages; the adjustment corrections are read as electrical potentials at the various junction points. The resistances, power units, and junction jacks are mounted on a panel, and are interconnected by jumpers. The closure and correction voltages are read with a special type feed‐back voltme

ISSN:0002-8606    

DOI:10.1029/TR028i006p00831

年代:1947

数据来源: WILEY

摘要:

The envelope method of analysis of vibrations is described briefly; examples are given of its application to the main phase of teleseisms and to microseisms, where beating occurs. The importance of its use in the theoretical study of microseisms caused by storms is emphasized, as it readily separates the minor component of the resultant vibration from the major component; the minor component had a period about 14 per cent greater than that of the major and contributed about 45 per cent of the total maximum amplitude of the beat cycle, in the examples given. This component has been ignored heretofore.The application of the method to the study of traffic microseisms is mentioned.

ISSN:0002-8606    

DOI:10.1029/TR028i006p00838

年代:1947

数据来源: WILEY

摘要:

Applications of electric counters to anemometer circuits, to make frequent ascents of the instrument tower unnecessary, and to give indications in convenient form, suitable for recording or reporting with a minimum of preparatory computation, are here outlined.

ISSN:0002-8606    

DOI:10.1029/TR028i006p00840

年代:1947

数据来源: WILEY

摘要:

Climatological stations are of two kinds, those established for climatological purposes, and those set up as part of a network for short range forecasting. The closeness of network and choice of sites for stations is not the same in these two classes; in general, the networks for forecasting are closer than those required for climatology. Climatological networks may be most open for insolation, daily maximum temperature, precipitation, wind, and visibility and least open for dally minimum temperature, and snowfall. Temporary stations and climatic profiling tributary to a long established primary station may serve in lieu of many permanent stations within a climatically coherent region. Thus the number of permanent stations can be made as few as one for each zone of one or two degrees of latitude and each zone of 509 to 2000 feet altitude within a large coherent region, each serving some 2000 sq mi in rough or coastal terrain or some 200,000 sq mi in interior plains country. Each zone, however, would require climatic tables for the several types of topographic locations, and detailed maps for completeness. The primary stations would have to be maintained with great care, to guard against errors and changing conditions of exposure.

ISSN:0002-8606    

DOI:10.1029/TR028i006p00845

年代:1947

数据来源: WILEY

摘要:

This paper is a study of the relative importance of Alberta and Great Basin Highs in producing temperatures at or below freezing in Florida, and the frequency with which freezing temperatures have been preceded by the following types of Lows: Atlantic Coastal storms, waves from the Gulf of Mexico, LOWS moving through the Southeastern States; deep Lows in the Upper Mississippi Valley; and those moving through the Great Lakes Region. The most favorable situation for freezing temperatures in Florida is found to be one in which there is an intense HIGH over the Great Basin with an extension into Alberta and with a deep stationary or westward‐moving LOW in the Great Lakes‐James Bay a

ISSN:0002-8606    

DOI:10.1029/TR028i006p00847

年代:1947

数据来源: WILEY

摘要:

Two years' data from 16 atmospheric radio‐noise measurement stations show sufficient consistencies in the relationship of the noise level and the geographic location of the observing station to indicate that a linear latitude trend approaches a definition of that relationship. The data on 2.5 and 5 Mc during night hours show a fair agreement with the United States Army Signal Corps predictions (RPU‐140). An even closer agreement exists between the observed data and a linear latitude relationship for each frequency. The average noise level for the northern hemisphere exhibits a variation, seasonal sine wave with an amplitude of about three units, superposed on a general decreasing trend for the past two years at the rate of about four units per y

ISSN:0002-8606    

DOI:10.1029/TR028i006p00854

年代:1947

数据来源: WILEY

摘要:

The numerical solution of the large number of simultaneous partial differential equations used in the theoretical design of the Netherlands waterways has previously been done manually at enormous expense of time and money. This paper shows how the same ends may be accomplished by an electrical network analogy.

ISSN:0002-8606    

DOI:10.1029/TR028i006p00861

年代:1947

数据来源: WILEY

摘要:

When ocean waves, moving through deep still water, encounter a current, moving at an angle with the wave direction, the waves undergo a change in length, steepness, and direction of travel. A theoretical development is given for these factors in terms of initial wave length and direction, and the magnitude of the current. Discussion is given of the action of a coastal current in affording protection against short period waves.

ISSN:0002-8606    

DOI:10.1029/TR028i006p00867

年代:1947

数据来源: WILEY

摘要:

Measurements of pressure variations with time at or near the ocean bottom provide a convenient means for determination of wave heights and periods. The wave characteristics are obtained from the pressure measurements through application of theoretical relationships associated with oscillatory waves. Laboratory experiments made to investigate the reliability of the theoretically determined correction factors indicate that the theoretical values result in wave heights about ten percent lower than the corresponding measured values. A brief analysis of irregular waves is included.

ISSN:0002-8606    

DOI:10.1029/TR028i006p00875

年代:1947

数据来源: WILEY