Roy, T. N. (Tribhuvan Nath) 1930
Overview
Works:  24 works in 49 publications in 1 language and 283 library holdings 

Genres:  Software 
Roles:  Author, Other 
Classifications:  DS485.G26, 934 
Publication Timeline
.
Most widely held works by
T. N Roy
The Ganges civilization : a critical archaeological study of the painted grey ware and northern black polished ware periods
of the Ganga Plains of India by
T. N Roy(
Book
)
12 editions published in 1983 in English and held by 93 WorldCat member libraries worldwide
12 editions published in 1983 in English and held by 93 WorldCat member libraries worldwide
Excavations at Rājghāt, 19571958, 19601965 by
A. K Narain(
Book
)
in English and held by 56 WorldCat member libraries worldwide
in English and held by 56 WorldCat member libraries worldwide
The excavations at Prahladpur, MarchApril 1963 by
A. K Narain(
Book
)
3 editions published in 1968 in English and held by 45 WorldCat member libraries worldwide
3 editions published in 1968 in English and held by 45 WorldCat member libraries worldwide
A study of northern black polished ware culture : an iron age culture of India by
T. N Roy(
Book
)
3 editions published in 1986 in English and held by 44 WorldCat member libraries worldwide
3 editions published in 1986 in English and held by 44 WorldCat member libraries worldwide
Excavations at Rājghāt : 1957  1958 ; 1960  1965 by
A. K Narain(
Book
)
5 editions published in 1977 in English and held by 6 WorldCat member libraries worldwide
5 editions published in 1977 in English and held by 6 WorldCat member libraries worldwide
Excavations at Rājghāt : 1957  1958 ; 1960  1965 by
A. K Narain(
Book
)
4 editions published in 1976 in English and held by 6 WorldCat member libraries worldwide
4 editions published in 1976 in English and held by 6 WorldCat member libraries worldwide
The organon modernised or the philosophy science and practice of the curative arts by
T. N Roy(
Book
)
1 edition published in 1926 in English and held by 3 WorldCat member libraries worldwide
1 edition published in 1926 in English and held by 3 WorldCat member libraries worldwide
HF (High Frequency) Maximum Usable Frequency (MUF) Model Uncertainty Assessment(
Book
)
2 editions published in 1987 in English and held by 2 WorldCat member libraries worldwide
A statistical analysis of observed oblique sounder median maximum observed frequencies (MOF) and predicted maximum usable frequencies (MUF) was used to assess the accuracy of highfrequency MUF prediction. A database of 13,054 hours of oblique sounder MOFs measured on 70 paths was compared with the predicted MUF values from MINIMUF3.5, MINIMUF 85, and an unrelated MUF model, the HF Broadcast WARC model (HFBC84). The data were screened into subsets to determine the effect of particular paths, path length and orientation, season, month, latitude, sunspot number, diurnal trends, geographic region, and sounder type. The accuracy of all three models was very close, with the MINIMUF3.5 model having the lowest RMS error of 4.44 MHz. MINIMUF 85 was next, with an RMS error of 4.58 MHz, and HFBC84 was last, with an error of 4.67 MHz, and MINIMUF 85 last, with 1.28 MHZ. Correlation was good for all three models. Correlation coefficients were .824, .819, and .827 for MINIMUF3.5, MINIMUF 85, and HFBC84, respectively. Future improvements to the MINIMUF model are discussed and current MUF computer algorithms are included in the appendices. Keywords include: HF propagation, MOF, Maximum observable frequency, MUF, Maximum usable frequency, and HF model, MINIMUF
2 editions published in 1987 in English and held by 2 WorldCat member libraries worldwide
A statistical analysis of observed oblique sounder median maximum observed frequencies (MOF) and predicted maximum usable frequencies (MUF) was used to assess the accuracy of highfrequency MUF prediction. A database of 13,054 hours of oblique sounder MOFs measured on 70 paths was compared with the predicted MUF values from MINIMUF3.5, MINIMUF 85, and an unrelated MUF model, the HF Broadcast WARC model (HFBC84). The data were screened into subsets to determine the effect of particular paths, path length and orientation, season, month, latitude, sunspot number, diurnal trends, geographic region, and sounder type. The accuracy of all three models was very close, with the MINIMUF3.5 model having the lowest RMS error of 4.44 MHz. MINIMUF 85 was next, with an RMS error of 4.58 MHz, and HFBC84 was last, with an error of 4.67 MHz, and MINIMUF 85 last, with 1.28 MHZ. Correlation was good for all three models. Correlation coefficients were .824, .819, and .827 for MINIMUF3.5, MINIMUF 85, and HFBC84, respectively. Future improvements to the MINIMUF model are discussed and current MUF computer algorithms are included in the appendices. Keywords include: HF propagation, MOF, Maximum observable frequency, MUF, Maximum usable frequency, and HF model, MINIMUF
Eastward ho! by
T. N Roy(
Book
)
1 edition published in 1947 in English and held by 2 WorldCat member libraries worldwide
1 edition published in 1947 in English and held by 2 WorldCat member libraries worldwide
Excavations at Rājghāt <19571958 ; 19601965> by
A. K Narain(
)
in Undetermined and held by 1 WorldCat member library worldwide
in Undetermined and held by 1 WorldCat member library worldwide
LUF (Lowest Usable Frequency) Model Uncertainty Assessment(
Book
)
1 edition published in 1987 in English and held by 1 WorldCat member library worldwide
The GROUNDWAVE model is compared to 84 surfacewave measurements made at frequencies of 20, 50, and 101.5 MHz for mountainous, hilly, and flat terrain. Surface wave transmission loss error is evaluated as a function of distance, frequency, terrain and receiving antenna height. The overall average measured transmission loss is 144 dB with an average interdecile range of 11 dB. The overall average calculated transmission loss is 141 dB, well within the interdecile range. When the model was tested as a function of terrain type, a trend toward understanding the transmission loss as the terrain became more irregular was apparent. GROUNDWAVE model error is evaluated as a function of input effective ground conductivity and effective ground relative dielectric constant also. By using constant values for these ground frequency, as is the usual practice, the possibility exists for substantial error in transmission loss calculations as a function of frequency. In the frequency range 2 to 20 MHz, results how the GROUNDWAVE model to underestimate transmission loss by an average of 13.1 dB for desert, mountainous, and hilly terrain. For the rich agricultural and marsh terrain, the GROUNDWAVE model overestimated the transmission loss by an average of only 1.9 dB. When the GROUNDWAVE model predicted transmission losses were compared to measured overocean data, it was found that the model severely overpredicted at frequencies greater than 18 MHz. This was attributed to the inability of the model to input nonstandard atmospheres
1 edition published in 1987 in English and held by 1 WorldCat member library worldwide
The GROUNDWAVE model is compared to 84 surfacewave measurements made at frequencies of 20, 50, and 101.5 MHz for mountainous, hilly, and flat terrain. Surface wave transmission loss error is evaluated as a function of distance, frequency, terrain and receiving antenna height. The overall average measured transmission loss is 144 dB with an average interdecile range of 11 dB. The overall average calculated transmission loss is 141 dB, well within the interdecile range. When the model was tested as a function of terrain type, a trend toward understanding the transmission loss as the terrain became more irregular was apparent. GROUNDWAVE model error is evaluated as a function of input effective ground conductivity and effective ground relative dielectric constant also. By using constant values for these ground frequency, as is the usual practice, the possibility exists for substantial error in transmission loss calculations as a function of frequency. In the frequency range 2 to 20 MHz, results how the GROUNDWAVE model to underestimate transmission loss by an average of 13.1 dB for desert, mountainous, and hilly terrain. For the rich agricultural and marsh terrain, the GROUNDWAVE model overestimated the transmission loss by an average of only 1.9 dB. When the GROUNDWAVE model predicted transmission losses were compared to measured overocean data, it was found that the model severely overpredicted at frequencies greater than 18 MHz. This was attributed to the inability of the model to input nonstandard atmospheres
Specification for HF Maximum Usable Frequency (MUF) Model(
Book
)
1 edition published in 1989 in English and held by 1 WorldCat member library worldwide
This report documents a highfrequency (HF) maximum usable frequency (MUF) model called MINIMUF85. Developed at the Naval Ocean Systems Center, this semiempirical model permits simplified HF propagation MUF predictions to be performed in nearrealtime. The model predicts the MUF for arbitrary input values of receiver/transmitter position, date, time (UT), and solar sunspot number. Several algorithms are contained in the model to describe the dependence of the MUF on solar activity, geomagnetic latitude, time of year, and time of day. An appendix contains the computer FORTRAN 77 code required to implement the fundamental features of this model. (RRH)
1 edition published in 1989 in English and held by 1 WorldCat member library worldwide
This report documents a highfrequency (HF) maximum usable frequency (MUF) model called MINIMUF85. Developed at the Naval Ocean Systems Center, this semiempirical model permits simplified HF propagation MUF predictions to be performed in nearrealtime. The model predicts the MUF for arbitrary input values of receiver/transmitter position, date, time (UT), and solar sunspot number. Several algorithms are contained in the model to describe the dependence of the MUF on solar activity, geomagnetic latitude, time of year, and time of day. An appendix contains the computer FORTRAN 77 code required to implement the fundamental features of this model. (RRH)
Excavations at Rājghāt 19571958, 19601965 P.1 by
Awadh K Narain(
Book
)
1 edition published in 1976 in Undetermined and held by 1 WorldCat member library worldwide
1 edition published in 1976 in Undetermined and held by 1 WorldCat member library worldwide
Sudden Ionospheric Disturbance Model Uncertainty Assessment(
Book
)
1 edition published in 1986 in English and held by 1 WorldCat member library worldwide
The impact of a sudden ionospheric disturbance (SID) on HF propagation is discussed. The development of an empirically derived relationship (SIDGRID) to model this impact is presented. The SIDGRID model compared to 198 observed sounder data points. For distances less than 1500 km, the shortrange prediction error was 0.5 MHz and in 95% of the tests the longrange prediction error was less than or equal to 2.0 MHz. Current FORTRAN and BASIC implementations of the model are given in Appendices C and D
1 edition published in 1986 in English and held by 1 WorldCat member library worldwide
The impact of a sudden ionospheric disturbance (SID) on HF propagation is discussed. The development of an empirically derived relationship (SIDGRID) to model this impact is presented. The SIDGRID model compared to 198 observed sounder data points. For distances less than 1500 km, the shortrange prediction error was 0.5 MHz and in 95% of the tests the longrange prediction error was less than or equal to 2.0 MHz. Current FORTRAN and BASIC implementations of the model are given in Appendices C and D
IONOPROP : an ionospheric propagation assessment program by
Herbert V Hitney(
Book
)
1 edition published in 1990 in Undetermined and held by 1 WorldCat member library worldwide
Offers an ionospheric propagation program which uses a combination of diurnal plot and world map to generate complicated propagation effects that vary in time and location
1 edition published in 1990 in Undetermined and held by 1 WorldCat member library worldwide
Offers an ionospheric propagation program which uses a combination of diurnal plot and world map to generate complicated propagation effects that vary in time and location
Science and Geeta by
T. N Roy(
Book
)
1 edition published in 1939 in English and held by 1 WorldCat member library worldwide
1 edition published in 1939 in English and held by 1 WorldCat member library worldwide
Airborne ManMade Radio Noise Assessment by
T. N Roy(
Book
)
2 editions published in 1981 in English and held by 1 WorldCat member library worldwide
An airborne manmade radio noise model has been developed and programmed on a graphics computer at the Naval Ocean Systems Center. This model provides a useful approximation to the geographical dependence of airborne man made radio noise in the continental United States. Radio noise maps produced from this model are used to evaluate the effect of manmade radio noise on the operation of meteor burst communication systems. Equations developed by Skomal (E.N. Skomal, ManMade Radio Noise, Van Nostrand Reinhold Co., New York, 1978) are used to construct the model. Two parametric equations are used to model the height gain of manmade radio noise as a function of distance, 0 to 150 miles, from the source. Coefficients for these equations are calculated from data measured over Seattle (W.E. Buehler and C.D. Lunden, IEEE Trans. Electromagnetic Compatibility, EMC8, 143152, 1966). Two hundred of the nation's largest cities and 62 of the largest counties and military installations are used as sources of radio noise in the computer program. Day and nighttime contours can be produced in the 25 to 75 MHz range for altitudes between 30 and 70 thousand feet
2 editions published in 1981 in English and held by 1 WorldCat member library worldwide
An airborne manmade radio noise model has been developed and programmed on a graphics computer at the Naval Ocean Systems Center. This model provides a useful approximation to the geographical dependence of airborne man made radio noise in the continental United States. Radio noise maps produced from this model are used to evaluate the effect of manmade radio noise on the operation of meteor burst communication systems. Equations developed by Skomal (E.N. Skomal, ManMade Radio Noise, Van Nostrand Reinhold Co., New York, 1978) are used to construct the model. Two parametric equations are used to model the height gain of manmade radio noise as a function of distance, 0 to 150 miles, from the source. Coefficients for these equations are calculated from data measured over Seattle (W.E. Buehler and C.D. Lunden, IEEE Trans. Electromagnetic Compatibility, EMC8, 143152, 1966). Two hundred of the nation's largest cities and 62 of the largest counties and military installations are used as sources of radio noise in the computer program. Day and nighttime contours can be produced in the 25 to 75 MHz range for altitudes between 30 and 70 thousand feet
Specification for HF Lowest Usable Frequency (LUF) Model(
Book
)
1 edition published in 1990 in English and held by 1 WorldCat member library worldwide
This report documents a high frequency (HF) lowest useable frequency (LUF) model called LUF. Developed at the Naval Ocean Systems Center, this semiempirical model permits simplified HF propagation predictions to be performed in nearrealtime. The model predicts the LUF for arbitrary input values of receiver/transmitter position, date, time (UT), Xray flux level, transmitter power, transmitter and receiver antenna type, transmitter and receiver antenna bearing, and required signaltonoise ratio. Several algorithms are contained in the model to describe the dependence of the LUF on these input parameters. An appendix contains the computer FORTRAN 77 code required to implement the fundamental features of this model. (rh)
1 edition published in 1990 in English and held by 1 WorldCat member library worldwide
This report documents a high frequency (HF) lowest useable frequency (LUF) model called LUF. Developed at the Naval Ocean Systems Center, this semiempirical model permits simplified HF propagation predictions to be performed in nearrealtime. The model predicts the LUF for arbitrary input values of receiver/transmitter position, date, time (UT), Xray flux level, transmitter power, transmitter and receiver antenna type, transmitter and receiver antenna bearing, and required signaltonoise ratio. Several algorithms are contained in the model to describe the dependence of the LUF on these input parameters. An appendix contains the computer FORTRAN 77 code required to implement the fundamental features of this model. (rh)
What the government has given and what it has taken back? Tuned to Development Mode: Impacts and performances of MNREGA down
the rural profile of India by
Balasubramaniam Swaminathan(
)
1 edition published in 2013 in English and held by 0 WorldCat member libraries worldwide
1 edition published in 2013 in English and held by 0 WorldCat member libraries worldwide
Airborne ManMade Radio Noise Assessment / T.N. Roy by
T. N Roy(
)
1 edition published in 1981 in Undetermined and held by 0 WorldCat member libraries worldwide
1 edition published in 1981 in Undetermined and held by 0 WorldCat member libraries worldwide
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Related Identities
 Narain, A. K. Other Author
 Singh, Purushottam 1940
 Agrawala, Prithvi Kumar
 NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA
 Banaras hindu university Department of ancient Indian history, culture and archaeology Editor
 Singh, Purushottam
 Sailors, D. B.
 Naval Ocean Systems Center (U.S.)
 Hitney, Herbert V. Author
 Moision, W. K.
Alternative Names
Roy, T.N. 1930
Roy, Tribhuvan Nath 1930
Tribhuvan Nath Roy
Tribhuvan Nath Roy 1930
Languages