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Paul, C. K.

Publications and source records attributed to Paul, C. K..

Remote sensing of environmental impact of land use activities

The capability to monitor land cover, associated in the past with aerial film cameras and radar systems, was discussed in regard to aircraft and spacecraft multispectral scanning sensors. A proposed thematic mapper with greater spectral and spatial resolutions for the fourth LANDSAT is expected to usher in new environmental monitoring capability. In addition, continuing improvements in image classification by supervised and unsupervised computer techniques are being operationally verified for discriminating environmental impacts of human activities on the land. The benefits of employing remote sensing for this discrimination was shown to far outweigh the incremental costs of converting to an aircraft-satellite multistage system.

Paul, C. K.

Remote sensing, land use, and demography - A look at people through their effects on the land

Relevant causes of failure by the remote sensing community in the urban scene are analyzed. The reasons for the insignificant role of remote sensing in urban land use data collection are called the law of realism, the incompatibility of remote sensing and urban management system data formats is termed the law of nominal/ordinal systems compatibility, and the land use/population correlation dilemma is referred to as the law of missing persons. The study summarizes the three laws of urban land use information for which violations, avoidance, or ignorance have caused the decline of present remote sensing research. Particular attention is given to the rationale for urban land use information and for remote sensing. It is shown that remote sensing of urban land uses compatible with the three laws can be effectively developed by realizing the 10 percent contribution of remote sensing to urban land use planning data collection.

Paul, C. K.

LUMIS: A Land Use Management Information System for urban planning

The Land Use Management Information System (LUMIS) consists of a methodology of compiling land use maps by means of air photo interpretation techniques, digitizing these and other maps into machine-readable form, and numerically overlaying these various maps in two computer software routines to provide land use and natural resource data files referenced to the individual census block. The two computer routines are the Polygon Intersection Overlay System (PIOS) and an interactive graphics APL program. A block referenced file of land use, natural resources, geology, elevation, slope, and fault-line items has been created and supplied to the Los Angeles Department of City Planning for the City's portion of the Santa Monica Mountains. In addition, the interactive system contains one hundred and seventy-three socio-economic data items created by merging the Third Count U.S. Census Bureau tapes and the Los Angeles County Secured Assessor File. This data can be graphically displayed for each and every block, block group, or tract for six test tracts in Woodland Hills, California. Other benefits of LUMIS are the knowledge of air photo availability, flight pattern coverage and frequencies, and private photogrammetry companies flying Southern California, as well as a formal Delphi study of relevant land use informational needs in the Santa Monicas.

Paul, C. K.

Results of phase one of land use information Delphi study

The Land Use Management Information System (LUMIS) is being developed for the city portion of the Santa Monica mountains. LUMIS incorporates data developed from maps and aerial photos as well as traditional land based data associated with routine city and county record keeping activities and traditional census data. To achieve the merging of natural resource data with governmental data LUMIS is being designed in accordance with restrictions associated with two other land use information systems currently being constructed by Los Angeles city staff. The two city systems are LUPAMS (Land Use Planning and Management System) which is based on data recorded by the County Assessor's office for each individual parcel of land in the city, and Geo-BEDS, a geographically based environmental data system.

Paul, C. K.

Remote sensing applications for urban planning - The LUMIS project

The Santa Monica mountains of Los Angeles consist primarily of complexly folded sedimentary marine strata with igneous and metamorphic rocks at the eastern end of the mountains. With the increased development of the Santa Monicas, a study was conducted to determine the critical land use data items in the mountains. Two information systems developed in parallel are described. One capitalizes on the City's present computer line printer system, and the second utilizes map overlay techniques on an interactive computer terminal. Results concerning population, housing, and land improvement illustrate the successful linking of ordinal and nominal data files in the interactive system.-

Paul, C. K.

Outer planet mission guidance and navigation for spinning spacecraft

The orbit determination accuracies, maneuver results, and navigation system specification for spinning Pioneer planetary probe missions are analyzed to aid in determining the feasibility of deploying probes into the atmospheres of the outer planets. Radio-only navigation suffices for a direct Saturn mission and the Jupiter flyby of a Jupiter/Uranus mission. Saturn ephemeris errors (1000 km) plus rigid entry constraints at Uranus result in very high velocity requirements (140 m/sec) on the final legs of the Saturn/Uranus and Jupiter/Uranus missions if only Earth-based tracking is employed. The capabilities of a conceptual V-slit sensor are assessed to supplement radio tracking by star/satellite observations. By processing the optical measurements with a batch filter, entry conditions at Uranus can be controlled to acceptable mission-defined levels (+ or - 3 deg) and the Saturn-Uranus leg velocity requirements can be reduced by a factor of 6 (from 139 to 23 m/sec) if nominal specified accuracies of the sensor can be realized.

Paul, C. K.

Advanced Pioneer guidance and navigation requirements for outer planet missions

Three advanced Pioneer missions to the outer planets are analyzed to assess midcourse velocity and navigation requirements. Selecting the results of the Saturn/Uranus mission as representative values for the three missions, the Earth-Saturn midcourse mean plus 3-sigma velocity correction is 80 m/sec. Earth-based radio-only tracking results in a navigational error of 2000 km at Saturn which in turn requires a mean plus 3-sigma velocity correction of 140 m/sec on the Saturn-Uranus leg to nullify this error mapped to Uranus. In contrast to these figures, if a proposed optical V-slit sensor is incorporated into the spacecraft navigational system, a Saturn B-plane error of only 350 km results with a corresponding required mean plus 3-sigma post-Saturn velocity correction of 23.2 m/sec. An 8000 km miss at Uranus results from radio-only tracking at Saturn which can be considerably reduced to 1400 km by utilizing the optical sensor during the Saturn flyby.

Paul, C. K.

The effects of trajectory characteristics on scientific objectives for major planetary orbiters.

Outline of specific solutions in the areas of attitude control, interplanetary trajectory parameters, and orbital configurations of major planetary spacecraft. It is shown that inertia wheel supplementation to a three-axis, stabilized attitude control system will substantially reduce propellant weight and attitude jet firings, especially when considering three-year orbital lifetimes as well as interplanetary trip times of several years. Eight interplanetary trajectory parameters including the earth injection energy and the declination of the launch asymptote are shown for a 1980 earth launch mission to Jupiter. The effects of the interplanetary trajectory parameters on the deboost velocities and resulting orbits about Jupiter are summarized. Orbital mode and science interfaces are defined, and a celestial mechanics experiment independent of earth tracking is briefly outlined.

Paul, C. K.