AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS
Overview
Works:  1,472 works in 1,501 publications in 1 language and 1,534 library holdings 

Genres:  Bibliography 
Classifications:  Z688.5, 025.02 
Publication Timeline
.
Most widely held works by
AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS
Pulse sounding with closely spaced receivers as a tool for measuring atmospheric motions and fine structure in the ionosphere(
Book
)
1 edition published in 1968 in English and held by 8 WorldCat member libraries worldwide
The objectives as well as the details of the conventional type of correlation analysis are critically examined and deficiencies are pointed out with suggestions for possible improvement. A new technique for measuring amplitude and phase fluctuations is then described, preliminary results are presented and the advantage of combining amplitude and phase information is emphasized. (Author)
1 edition published in 1968 in English and held by 8 WorldCat member libraries worldwide
The objectives as well as the details of the conventional type of correlation analysis are critically examined and deficiencies are pointed out with suggestions for possible improvement. A new technique for measuring amplitude and phase fluctuations is then described, preliminary results are presented and the advantage of combining amplitude and phase information is emphasized. (Author)
Correlations of temperature, pressure, and density, to 30 kilometers by Allen E Cole(
Book
)
1 edition published in 1965 in English and held by 4 WorldCat member libraries worldwide
Arrays of means and standard deviations of temperature and density for 2km intervals of altitude up to 30 km, together with inter and intralevel coefficients of correlation of density with density, temperature with temperature, and temperature with density, are presented for midseason months at four locations. Temperature and density at the same level are, in general, negatively correlated at altitudes below 30 km. A level of minimum seasonal and latitudinal temperature variability occurs between 12 and 14 km. Seasonal temperature variability is largest near the earth's surface, and the latitudinal variability is greatest between 14 and 17 km. Density variability is least near 8 km, the isopycnic level. A level of maximum seasonal and latitudinal density variability occurs between 12 and 14 km. Means and standard deviations of surface pressure and coefficients of correlation between surface pressure and temperatures at levels up to 30 km are presented and discussed. An examination of the relationship between the standard deviation of surface pressure and the coefficients of variation of density at the level of maximum variability indicates that the variation of surface pressure is not a good index of variations in the vertical density distribution. (Author)
1 edition published in 1965 in English and held by 4 WorldCat member libraries worldwide
Arrays of means and standard deviations of temperature and density for 2km intervals of altitude up to 30 km, together with inter and intralevel coefficients of correlation of density with density, temperature with temperature, and temperature with density, are presented for midseason months at four locations. Temperature and density at the same level are, in general, negatively correlated at altitudes below 30 km. A level of minimum seasonal and latitudinal temperature variability occurs between 12 and 14 km. Seasonal temperature variability is largest near the earth's surface, and the latitudinal variability is greatest between 14 and 17 km. Density variability is least near 8 km, the isopycnic level. A level of maximum seasonal and latitudinal density variability occurs between 12 and 14 km. Means and standard deviations of surface pressure and coefficients of correlation between surface pressure and temperatures at levels up to 30 km are presented and discussed. An examination of the relationship between the standard deviation of surface pressure and the coefficients of variation of density at the level of maximum variability indicates that the variation of surface pressure is not a good index of variations in the vertical density distribution. (Author)
Acoustic Surface Wave Diffraction and Beam Steering(
Book
)
1 edition published in 1973 in English and held by 3 WorldCat member libraries worldwide
The report contains a detailed description of diffraction in acoustic surface wave devices. This source of loss is highly important in the design and realization of bandpass filters, long time delay lines and other devices for electronic sensors and communications systems. A complete review of acoustic surface wave diffraction on anisotropic substrates is presented. Full experimental verification of theory is provided. Complete computer program listings and descriptions are provided. The limits of applicability of the parabolic velocity surface theory are quantitatively delineated. Universal diffraction loss design curves are given for all parabolic materials. A limitation in the use of the exact angular spectrum of waves theory occurs for materials having a power flow angle slope approximately  1 unless the velocity surfaces are very accurately known. Both YZ LiNbO3 and 161/2 degree double rotated LiNbO3 fall in this category. Approximate diffraction loss design curves are given for YZ LiNbO3. A complete tabular summary of all important material properties affecting acoustic surface wave device design is included. (Author)
1 edition published in 1973 in English and held by 3 WorldCat member libraries worldwide
The report contains a detailed description of diffraction in acoustic surface wave devices. This source of loss is highly important in the design and realization of bandpass filters, long time delay lines and other devices for electronic sensors and communications systems. A complete review of acoustic surface wave diffraction on anisotropic substrates is presented. Full experimental verification of theory is provided. Complete computer program listings and descriptions are provided. The limits of applicability of the parabolic velocity surface theory are quantitatively delineated. Universal diffraction loss design curves are given for all parabolic materials. A limitation in the use of the exact angular spectrum of waves theory occurs for materials having a power flow angle slope approximately  1 unless the velocity surfaces are very accurately known. Both YZ LiNbO3 and 161/2 degree double rotated LiNbO3 fall in this category. Approximate diffraction loss design curves are given for YZ LiNbO3. A complete tabular summary of all important material properties affecting acoustic surface wave device design is included. (Author)
Simulation experiments in twoway controlled carrier transmission(
Book
)
3 editions published in 1963 in English and held by 3 WorldCat member libraries worldwide
A controlled carrier system, the power reductions due to controlled carrier transmission, and the results of an analog computer simulation demonstrating various aspects of controlled carrier operation are discussed. In addition, communication performance improvements in tropospheric scatter systems that may be obtained through the use of controlled carrier are cited, and related to corresponding improvements obtained with diversity and coding. (Author)
3 editions published in 1963 in English and held by 3 WorldCat member libraries worldwide
A controlled carrier system, the power reductions due to controlled carrier transmission, and the results of an analog computer simulation demonstrating various aspects of controlled carrier operation are discussed. In addition, communication performance improvements in tropospheric scatter systems that may be obtained through the use of controlled carrier are cited, and related to corresponding improvements obtained with diversity and coding. (Author)
Research directed toward the study of the radiation damage thresholds of the elements(
Book
)
3 editions published in 1962 in English and held by 3 WorldCat member libraries worldwide
The changes in residual electrical resistance produced by bombardment with high energy electrons were measured for a number of metals as a function of electron energy in the range from 0.5 to 1.5 Mev. The irradiations were performed at 20 K and lower and recovery measurements were made up to 300 K. The production curves were analyzed using simple displacement theory and the following values were found for the average threshold energies: Al32 ev; Augreater than 40 ev; Ag28 ev; Cu22 ev; Fe24 ev; Mo37 ev; Ni24 ev; Ti29 ev; and W greater than 35 ev. Approximate values for the resistivities of Frenkel pairs (in units of microhms cm per atomic per cent) were also obtained as follows: Al3.4; Ag1.4; Cu1.3; Fe12.5; Mo4.5; Ni3.2, and Ti42. In the case of Al it was necessary to take secondary defect production into account; and a number of representative theoretical curves, based on different assumptions concerning the process of secondary defect production, are included. The behavior of Zn was anomalous in that the added resistivity was not a linear function of electron dose at 20 K. (Author)
3 editions published in 1962 in English and held by 3 WorldCat member libraries worldwide
The changes in residual electrical resistance produced by bombardment with high energy electrons were measured for a number of metals as a function of electron energy in the range from 0.5 to 1.5 Mev. The irradiations were performed at 20 K and lower and recovery measurements were made up to 300 K. The production curves were analyzed using simple displacement theory and the following values were found for the average threshold energies: Al32 ev; Augreater than 40 ev; Ag28 ev; Cu22 ev; Fe24 ev; Mo37 ev; Ni24 ev; Ti29 ev; and W greater than 35 ev. Approximate values for the resistivities of Frenkel pairs (in units of microhms cm per atomic per cent) were also obtained as follows: Al3.4; Ag1.4; Cu1.3; Fe12.5; Mo4.5; Ni3.2, and Ti42. In the case of Al it was necessary to take secondary defect production into account; and a number of representative theoretical curves, based on different assumptions concerning the process of secondary defect production, are included. The behavior of Zn was anomalous in that the added resistivity was not a linear function of electron dose at 20 K. (Author)
Bibliography of lunar and planetary research : supplement no. 4, 1968 by
Air Force Cambridge Research Laboratories (U.S.)(
Book
)
3 editions published between 1961 and 1969 in English and held by 3 WorldCat member libraries worldwide
A bibliography of lunar and planetary research articles published in 1962 is presented with both subject and author entries. The subject listings, which are abstracted, fall into the following major categories: astrobiology, comets, exploration programs and probes, meteorite craters and cratering effects, meteors and meteorites, the moon, origin of the solar system, the planets, and tektites. (Author)
3 editions published between 1961 and 1969 in English and held by 3 WorldCat member libraries worldwide
A bibliography of lunar and planetary research articles published in 1962 is presented with both subject and author entries. The subject listings, which are abstracted, fall into the following major categories: astrobiology, comets, exploration programs and probes, meteorite craters and cratering effects, meteors and meteorites, the moon, origin of the solar system, the planets, and tektites. (Author)
New methods of solving algebraic equations(
Book
)
1 edition published in 1963 in English and held by 3 WorldCat member libraries worldwide
The main problem of solving an algebraic equation which is of higher degree is that of factorizing the polynomial in a product of polynomial factors of Degrees 1 and 2. A class of linear factors can be found with the aid of a power table. When these evident real roots are eliminated, the residue polynomial can be factorized in quadratic polynomial factors. A 'Table Method' is devised by which coefficient approximations can easily be found, and methods are shown for use when solving a quartic equation and when solving a sextic equation. (Author)
1 edition published in 1963 in English and held by 3 WorldCat member libraries worldwide
The main problem of solving an algebraic equation which is of higher degree is that of factorizing the polynomial in a product of polynomial factors of Degrees 1 and 2. A class of linear factors can be found with the aid of a power table. When these evident real roots are eliminated, the residue polynomial can be factorized in quadratic polynomial factors. A 'Table Method' is devised by which coefficient approximations can easily be found, and methods are shown for use when solving a quartic equation and when solving a sextic equation. (Author)
Investigation of various activator  refractory substrate combinations by John H Affleck(
Book
)
3 editions published between 1961 and 1962 in English and held by 3 WorldCat member libraries worldwide
A number of dispenser cathodes were tested in this investigation that exhibit the low work functions necessary for highcurrent density cathodes. Precautions may be taken to keep the evaporation rate at an acceptable level. These results suggest that a wide choice is possible in the materials capable of producing a barium dispenser cathode. (Author)
3 editions published between 1961 and 1962 in English and held by 3 WorldCat member libraries worldwide
A number of dispenser cathodes were tested in this investigation that exhibit the low work functions necessary for highcurrent density cathodes. Precautions may be taken to keep the evaporation rate at an acceptable level. These results suggest that a wide choice is possible in the materials capable of producing a barium dispenser cathode. (Author)
The Design of a more complex building block for digital systems by
W. F King(
Book
)
1 edition published in 1967 in English and held by 2 WorldCat member libraries worldwide
Design techniques for a complex building block for digital systems are developed in this paper. Of particular interest are building blocks that are applicable to the nonstandard portions of digital systemsfor example, the control circuitry of a computer. It is shown that a complex block for these applications must have considerable interconnection internal to the integrated circuit chip and multipurpose or multifunction capabilities. A multipurpose logic block (MLB) is proposed as the complex building block based on these constraints. The block has r signal or data inputs and s control inputs and can realize any one of a set of Boolean functions, depending on how the control inputs are connected. The control inputs can be connected to ground, to the supply voltage, or to signal inputs. An algorithm is presented with which an MLB can be designed to realize a specific number of functions. In one example, an MLB is developed for obtaining certain functions of three variables; the functions are sum, majority, equivalence, NOR, and AND. A working demonstration model is designed and constructed from the example. (Author)
1 edition published in 1967 in English and held by 2 WorldCat member libraries worldwide
Design techniques for a complex building block for digital systems are developed in this paper. Of particular interest are building blocks that are applicable to the nonstandard portions of digital systemsfor example, the control circuitry of a computer. It is shown that a complex block for these applications must have considerable interconnection internal to the integrated circuit chip and multipurpose or multifunction capabilities. A multipurpose logic block (MLB) is proposed as the complex building block based on these constraints. The block has r signal or data inputs and s control inputs and can realize any one of a set of Boolean functions, depending on how the control inputs are connected. The control inputs can be connected to ground, to the supply voltage, or to signal inputs. An algorithm is presented with which an MLB can be designed to realize a specific number of functions. In one example, an MLB is developed for obtaining certain functions of three variables; the functions are sum, majority, equivalence, NOR, and AND. A working demonstration model is designed and constructed from the example. (Author)
A study of the far infrared properties of crystals(
Book
)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
A study was made of a far infrared spectrometer for studying the properties of crystals. The frequency distributions for a diatomic linear chain of Na23Cl35.5 were compared with those of a mix crystal of NaCl35 and NaCl37. Eigenfrequencies of NaCl at room temperature and 2K were calculated. Tests were made to enhance the harmonic output of the 3J31 magnetron
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
A study was made of a far infrared spectrometer for studying the properties of crystals. The frequency distributions for a diatomic linear chain of Na23Cl35.5 were compared with those of a mix crystal of NaCl35 and NaCl37. Eigenfrequencies of NaCl at room temperature and 2K were calculated. Tests were made to enhance the harmonic output of the 3J31 magnetron
The volume density of radar echoes from meteor trails, in the case of uniform distribution of the heliocentric radiants(
Book
)
2 editions published in 1961 in English and held by 2 WorldCat member libraries worldwide
General formulas are derived, which express the volume density of the reflection points of the meteor trails, as well as the volume density of the echoes revealed by a radar, in terms of the heliocentric velocity distribution. Then, as an application, the volume density of the reflection points is evaluated, in the case of uniform distribution of heliocentric radiants. The expression of the volume density of the readar echoes is presented. (Author)
2 editions published in 1961 in English and held by 2 WorldCat member libraries worldwide
General formulas are derived, which express the volume density of the reflection points of the meteor trails, as well as the volume density of the echoes revealed by a radar, in terms of the heliocentric velocity distribution. Then, as an application, the volume density of the reflection points is evaluated, in the case of uniform distribution of heliocentric radiants. The expression of the volume density of the readar echoes is presented. (Author)
A bibliography of the electrically exploded conductor phenomenon by
William George Chace(
Book
)
2 editions published between 1962 and 1965 in English and held by 2 WorldCat member libraries worldwide
The bibliography includes abstracts of reports on the exploding conductor (exploding wire) phenomenon published from 1774 through 1966. There is also some coverage of important papers in adjacent areas of spectroscopy and instrumentation. Arrangement is by subject group, alphabetically by authors
2 editions published between 1962 and 1965 in English and held by 2 WorldCat member libraries worldwide
The bibliography includes abstracts of reports on the exploding conductor (exploding wire) phenomenon published from 1774 through 1966. There is also some coverage of important papers in adjacent areas of spectroscopy and instrumentation. Arrangement is by subject group, alphabetically by authors
Semantic interpretation of deep structure for naturallanguage computer input by Sara Regina Murphey(
Book
)
1 edition published in 1960 in English and held by 2 WorldCat member libraries worldwide
The theory of transformational grammars represents the linguists' most elaborate attempt to date to formalize the syntactic structure of English. The result of analyzing a sentence according to a transformational grammar is a socalled 'deep structure, ' which expresses various information about the constituent portions of the sentence in a treelike form. In view of the relatively high state of development of the transformational theory, it is natural to use it as the basis for the 'front end' of an Englishunderstanding program. The system discussed in the report provides a general method of interpretation of transformationally parsed sentences for use in questionanswering. It is based on a general scheme for using the information contained in the deep structures to interrogate a data base. The primary effort is aimed at handling a wide variety of complex syntactic structures, with particular concern for the problem of embedded structures. The system provides a general facility for handling syntactic sturctures, to which a user can add routines corresponding to the specific nouns, verbs, and adjectives he wants to use. The present implementation includes a vocabulary suitable for dealing with sets; the noun, verb, and adjective routines for this area of discourse constitute about 10% of the entire program. (Author)
1 edition published in 1960 in English and held by 2 WorldCat member libraries worldwide
The theory of transformational grammars represents the linguists' most elaborate attempt to date to formalize the syntactic structure of English. The result of analyzing a sentence according to a transformational grammar is a socalled 'deep structure, ' which expresses various information about the constituent portions of the sentence in a treelike form. In view of the relatively high state of development of the transformational theory, it is natural to use it as the basis for the 'front end' of an Englishunderstanding program. The system discussed in the report provides a general method of interpretation of transformationally parsed sentences for use in questionanswering. It is based on a general scheme for using the information contained in the deep structures to interrogate a data base. The primary effort is aimed at handling a wide variety of complex syntactic structures, with particular concern for the problem of embedded structures. The system provides a general facility for handling syntactic sturctures, to which a user can add routines corresponding to the specific nouns, verbs, and adjectives he wants to use. The present implementation includes a vocabulary suitable for dealing with sets; the noun, verb, and adjective routines for this area of discourse constitute about 10% of the entire program. (Author)
SEMICONDUCTOR MATERIALS by
A. D Johnson(
Book
)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
The future materials problems should see increased efforts on techniques for tailormaking semiconductors for certain desir prop r ies. Mixi g of miscible compounds appears promising in this respect. Epit xi l vapor grow h techniques also warrant further exploitation. Other approaches for specific applications are expected to be emphasized, such as mixed valency semiconductors for high temp rature thermoelectric elements. Theoretical a vances are expected in terms of nergy band structure based on cyclotron resonance and related measurements. Investiga ions will continue to be based on the role of imp rf ctions i e icon uctor uthor)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
The future materials problems should see increased efforts on techniques for tailormaking semiconductors for certain desir prop r ies. Mixi g of miscible compounds appears promising in this respect. Epit xi l vapor grow h techniques also warrant further exploitation. Other approaches for specific applications are expected to be emphasized, such as mixed valency semiconductors for high temp rature thermoelectric elements. Theoretical a vances are expected in terms of nergy band structure based on cyclotron resonance and related measurements. Investiga ions will continue to be based on the role of imp rf ctions i e icon uctor uthor)
Evaluation of an Arctic icefree land site and results of C130 aircraft test landings, Polaris Promontory, North Greenland
19581959 by
Stanley M Needleman(
Book
)
1 edition published in 1961 in English and held by 2 WorldCat member libraries worldwide
Fiel investigations of an icefree land area at Polaris Promontory, Hall Land in northwest Greenland were undertaken to determine if this area could support austere military aircraft operations. Detailed scientific observations of the geology, meteorology, and natural terrain features of the area were made, thorough investigations of the soil features and bearing strength were conducted, and an airstrip was prepared and marked. Successful test landings by a C130 aircraft were made on the airstrip. Possible alternate airstrip sites were studied and conclusions drawn on the usability of such icefree land sites for military activities. The selection of specific sites in such areas by lowaltitude aerial reconnaissance and applied photogeologic interpretation methods is feasible and practical. Such techniques, when employed by professionals with considerable field experience in the Arctic regions, are reliable, rapid, and inexpensive. (Author)
1 edition published in 1961 in English and held by 2 WorldCat member libraries worldwide
Fiel investigations of an icefree land area at Polaris Promontory, Hall Land in northwest Greenland were undertaken to determine if this area could support austere military aircraft operations. Detailed scientific observations of the geology, meteorology, and natural terrain features of the area were made, thorough investigations of the soil features and bearing strength were conducted, and an airstrip was prepared and marked. Successful test landings by a C130 aircraft were made on the airstrip. Possible alternate airstrip sites were studied and conclusions drawn on the usability of such icefree land sites for military activities. The selection of specific sites in such areas by lowaltitude aerial reconnaissance and applied photogeologic interpretation methods is feasible and practical. Such techniques, when employed by professionals with considerable field experience in the Arctic regions, are reliable, rapid, and inexpensive. (Author)
An investigation of anomalous transhorizon radiowave propagation over irregular terrain(
Book
)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
The anomalous nighttime propagation of radio waves was studied at frequencies of 9100, 2800, and 840 Mc/s observed on the 108km path from Rochester to Ithaca, New York. Previously proposed theories that explain anomalous propagation by ducting, reflection, or diffraction fail to explain the irregular behavior studied. Further radio measurements in the form of (1) sampling the 9100Mc/s signal at 15 sites located along the propagation path, (2) heightgain measurements at 9100 Mc/s at the receiver site, and (3) swinging the 2800Mc/s antennas 2 deg off the great circle path were undertaken in order to arrive at an explanation of the phenomenon. Finally, a theory based on the formation of elevated superrefractive layers situated over two lakes crossing the path is proposed to explain the anomalous propagation. (Author)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
The anomalous nighttime propagation of radio waves was studied at frequencies of 9100, 2800, and 840 Mc/s observed on the 108km path from Rochester to Ithaca, New York. Previously proposed theories that explain anomalous propagation by ducting, reflection, or diffraction fail to explain the irregular behavior studied. Further radio measurements in the form of (1) sampling the 9100Mc/s signal at 15 sites located along the propagation path, (2) heightgain measurements at 9100 Mc/s at the receiver site, and (3) swinging the 2800Mc/s antennas 2 deg off the great circle path were undertaken in order to arrive at an explanation of the phenomenon. Finally, a theory based on the formation of elevated superrefractive layers situated over two lakes crossing the path is proposed to explain the anomalous propagation. (Author)
LUNAR REFLECTION STUDY by Brian H Claxton(
Book
)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
The effective bandwidth of the lunar reflection path was determined. Doppler shift, signal strength, and amplitude fading of CW signals were measured, and the results analyzed and compared to theoretical predictions. Double sideband suppressed carrier transmissions centered at 915 Mc, with audio frequency modulation to produce two signals separated in frequency by a small amount, were re lected from the moon and received. The amplitudes of the two sidebands were separately recorded, and their correlation coefficient computed to give a measure of the quality of the circuit. Fortyfive determinations of the correlation coefficient for 500 cps sideband separation gave a value of .26! .07, showing that the coherent bandwidth of the moon reflection path is extremely narrow. A standard word list was transmitted as a test on the actual quality to be expected of a voice circuit using relatively unsophisticated terminal equipment. A panel of listeners correctly ascertained 74% of the moonreflected words, whereas 95% o the words on a similar list presented without distortion but in the same signal/white noise environment, were correctly judged. The difference is attributed to fading more than to distortion of the moonreflected words. (Author)
2 editions published in 1962 in English and held by 2 WorldCat member libraries worldwide
The effective bandwidth of the lunar reflection path was determined. Doppler shift, signal strength, and amplitude fading of CW signals were measured, and the results analyzed and compared to theoretical predictions. Double sideband suppressed carrier transmissions centered at 915 Mc, with audio frequency modulation to produce two signals separated in frequency by a small amount, were re lected from the moon and received. The amplitudes of the two sidebands were separately recorded, and their correlation coefficient computed to give a measure of the quality of the circuit. Fortyfive determinations of the correlation coefficient for 500 cps sideband separation gave a value of .26! .07, showing that the coherent bandwidth of the moon reflection path is extremely narrow. A standard word list was transmitted as a test on the actual quality to be expected of a voice circuit using relatively unsophisticated terminal equipment. A panel of listeners correctly ascertained 74% of the moonreflected words, whereas 95% o the words on a similar list presented without distortion but in the same signal/white noise environment, were correctly judged. The difference is attributed to fading more than to distortion of the moonreflected words. (Author)
DURATION AND UNUSUAL EXTREMES OF COLD(
Book
)
2 editions published between 1970 and 1972 in English and held by 2 WorldCat member libraries worldwide
The study supplements 'Duration and Unusual Extremes of Cold, AD710 611 dated 26 June 1970. It presents revised values of lowtemperature extremes that correspond to recently modified guidance on acceptable risk. A low temperature of 50 degrees F corresponds to the value that equipment will encounter with a 50 percent probability when it is exposed in small recordmaking cold basins of Siberia during the coldest month. The 50 percent probability level is now applicable to operation of equipment. Associated with this extreme is a 1month cycle of temperatures that are characteristic of the complete thermal regime in which a minimum of 50 degrees F is imbedded. When not in operation, equipment must be able to withstand temperatures in the 81 to 88 degree F range for 1 hour, and below 29 degrees F for 32 days. (Author Modified Abstract)
2 editions published between 1970 and 1972 in English and held by 2 WorldCat member libraries worldwide
The study supplements 'Duration and Unusual Extremes of Cold, AD710 611 dated 26 June 1970. It presents revised values of lowtemperature extremes that correspond to recently modified guidance on acceptable risk. A low temperature of 50 degrees F corresponds to the value that equipment will encounter with a 50 percent probability when it is exposed in small recordmaking cold basins of Siberia during the coldest month. The 50 percent probability level is now applicable to operation of equipment. Associated with this extreme is a 1month cycle of temperatures that are characteristic of the complete thermal regime in which a minimum of 50 degrees F is imbedded. When not in operation, equipment must be able to withstand temperatures in the 81 to 88 degree F range for 1 hour, and below 29 degrees F for 32 days. (Author Modified Abstract)
Automated routines in technical services by
Patricia T Sievers(
Book
)
2 editions published in 1964 in English and held by 1 WorldCat member library worldwide
This paper discusses the approach to automation taken by the AFCRL Research Library, applicable to libraries in general. A brief review of the current market of equipments and techniques is followed by guidelines this library will use in order to effect total systems automation. The AFCRL Research Library monograph processing system is discussed as an application of the techniques described. It covers the preliminary search routines using an MP3 Polaroid camera, the cataloging routines making use of various machinegenerated authority lists, the bibliographic encoding and catalogcard generation using tape typewriters, and the specialpurpose dataprocessing device, the Itek Crossfiler, developed for this library. (Author)
2 editions published in 1964 in English and held by 1 WorldCat member library worldwide
This paper discusses the approach to automation taken by the AFCRL Research Library, applicable to libraries in general. A brief review of the current market of equipments and techniques is followed by guidelines this library will use in order to effect total systems automation. The AFCRL Research Library monograph processing system is discussed as an application of the techniques described. It covers the preliminary search routines using an MP3 Polaroid camera, the cataloging routines making use of various machinegenerated authority lists, the bibliographic encoding and catalogcard generation using tape typewriters, and the specialpurpose dataprocessing device, the Itek Crossfiler, developed for this library. (Author)
On the transfer function for a radio scatter channel by Harry Elmer Hardebeck(
Book
)
2 editions published in 1962 in English and held by 1 WorldCat member library worldwide
The formal proof that the components of a signal produced by the scattering of a monochromatic wave by random irregularities of refractive index are independently and normally distributed cannot be made with existing mcependent central limit theorems. What is needed is a theorem that sets forth the maximum rate at which random variables may become more correlated as their number increases and yet allows the distribution function of their sum to approach the normal distribution. The theorem should be extendable to the case of random vectors of finite dimension. Further, the assumption of a correlation function for the fluctuation structure cannot produce the probability distribution function for H(omega sub i, t sub j) . One can, however, calculate the power spectrum of the scattered wave from this correlation function. Assuming an isotropic exponential correlation function in both space and time, the power spectrum of y(t) was found for a monochromatic x(t). The result is not unreasonable compared to some experimental results. A correlation function in frequency was also computed. Unfortunately, sweep frequency experiments have not produced enough data as yet to make it possible to compare the data with the computed correlation function. (Author)
2 editions published in 1962 in English and held by 1 WorldCat member library worldwide
The formal proof that the components of a signal produced by the scattering of a monochromatic wave by random irregularities of refractive index are independently and normally distributed cannot be made with existing mcependent central limit theorems. What is needed is a theorem that sets forth the maximum rate at which random variables may become more correlated as their number increases and yet allows the distribution function of their sum to approach the normal distribution. The theorem should be extendable to the case of random vectors of finite dimension. Further, the assumption of a correlation function for the fluctuation structure cannot produce the probability distribution function for H(omega sub i, t sub j) . One can, however, calculate the power spectrum of the scattered wave from this correlation function. Assuming an isotropic exponential correlation function in both space and time, the power spectrum of y(t) was found for a monochromatic x(t). The result is not unreasonable compared to some experimental results. A correlation function in frequency was also computed. Unfortunately, sweep frequency experiments have not produced enough data as yet to make it possible to compare the data with the computed correlation function. (Author)
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Atmospheric circulation Atmospheric density Atmospheric temperature Correlation (Statistics) Doppler effect Electric currents Electronic data processing Exploding wire phenomena Grammar, Comparative and generalSyntax Greenland Hercules (Turboprop transports) Humanmachine systems Integrated circuits IonosphereMeasurement LibrariesAutomation Logic circuits Lunar exploration Lunar surface radio communication Moon Planets Plasma (Ionized gases) Programming languages (Electronic computers) Radio frequency RadioTransmitters and transmission Radio waves Runways (Aeronautics) Semantics Semiconductors Space sciences Switching circuits Technical services (Libraries)
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