Digital Commons Network^™

On The Prospects Of Turning Pressure Pulsation To Good Account For Intensification Of Heat Exchange In The Coolers Of Reciprocating Compressors, M. Luszczycki, J. Kowalski

International Compressor Engineering Conference

No abstract provided.

Some Considerations In Refrigerant Compressor Valve Structural Reliability And Failure Mechanisms, J. S. Laub

International Compressor Engineering Conference

No abstract provided.

Influence Of Seat Positioning And Seat Design On Valve Fatigue Performance, R. Dusil, B. Johansson

International Compressor Engineering Conference

No abstract provided.

Impact Stresses In Flapper Valves - A Finite Element Analysis, J. O. Nilsson, L. Nilsson, M. Oldenburg

International Compressor Engineering Conference

No abstract provided.

Analysis Of Cavity Resonance In 5 Hp Hermetic Reciprocating Compressor With Elliptical Shell, T. Matsuzaka, T. Hayashi, H. Shinto

International Compressor Engineering Conference

No abstract provided.

Gas Forces On Disc Valves, J. Fleming, J. Brown, R. Davidson

International Compressor Engineering Conference

No abstract provided.

Performance Of Automatic Compressor Valves, J. Brown, R. Davidson, J. Fleming

International Compressor Engineering Conference

No abstract provided.

Measurement Of Tube Bundle Coolers Under Working Conditions, A. Liska

International Compressor Engineering Conference

No abstract provided.

Analytical Model Of An Oil-Free Screw Compressor, J. Brablik

International Compressor Engineering Conference

No abstract provided.

Correlation Of Spectral Classes Derived From Landsat Mss Data To Soil Series And Soil Conditions For Jasper County, Indiana, E. J. Hinzel, R. A. Weismiller, F. R. Kirschner

LARS Symposia

The process of soil survey has been an on-going program in the United States since the early 1930's with aerial photography greatly increasing the speed and accuracy of the survey. Recent innovations in remote sensing techniques have offered the soil scientist a tool to aid in surveying the soils of this country and the world.

Recent work utilizing computer-aided analysis of Landsat MSS data resulted in a spectral soils map of Jasper County, Indiana. This map displayed fifty-two spectral classes which represented the soils found within six distinct parent material areas.

A correlation of the spectral classes with the soils …

Future Global Information Needs For Land Resources, Rudy Dudal

LARS Symposia

No abstract provided.

Application Of Multispectral Data In Developing A Detailed Soil Survey Of Ford County, Illinois, L. M. Kiefer, E. E. Voss, F. R. Kirschner, R. A. Weismiller, S. J. Kristof, L. J. Lund

LARS Symposia

A soil survey program was initiated in Ford County, Illinois in October 1979 with a scheduled completion date of September 1984. The soils of this county are Mollisols (>95%) with dominant drainage classes (>90%) being poorly and somewhat poorly drained. The area has <5% woodland and a minimum of other permanent vegetation. With the initiation of the survey it was decided to use spectral maps as an aid in field mapping.

Spectral maps have been developed by computer-aided digital analysis of Landsat data covering Ford County. The classification maps were developed using a layered classifier technique with the initial decision in the decision tree being related to parent material boundaries that were applied to the data set after field investigations. The parent materials of this area …

Application Of Multispectral Reflectance Studies Of Soils: Pre-Landsat, S. J. Kristof, M. F. Baumgardner, R. A. Weismiller, Shirley Davis

LARS Symposia

It was recognized in the 1960's that measuring the spectral, spatial and temporal variation of electromagnetic fields reflected and emitted from the Earth's surface had many potential applications in the field of agriculture. As a result, computer-implemented pattern recognition techniques were used to analyze multispectral data for the purpose of delineating soil differences. Spectral data were obtained (1) in the laboratory by scanning soil samples with a double-beam spectrophotometer (Beckman DK-2A) and (2) in the field by scanning large areas of soils with an airborne multispectral scanner.

The results obtained through this early research clearly illustrated relationships between the reflected …

Nasa's Applications Data Service, Jan Heuser

LARS Symposia

Applications are evolving in the 80's from an era of exploration and inventory into an era of "exploitation". Atmospheric and earth scientists are collecting data to develop models and an understanding of natural phenomena. These models will be applied to research for nationwide problems such as pollution monitoring and control, water resources management, energy resources exploration and allocation, or natural disaster warning/alleviation. This means that discipline scientists i n agriculture, oceans, atmospheres and others are tackling applications which require the timely access and integration of data from a dozen or more sources.

To meet these data access and integration challenges, …

Lineament Mapping In Northern Sweden From Landsat Images Using Orthogonal Image Transforms, Christer L. Andersson, Hans Hauska

LARS Symposia

The emphasis of this paper is put on mapping of geological linear structures, and in particular the correlation between these structures orientation and geological or geophysical data. It is also the intention of the authors to present a method to map these structures more objectively than up to now.

Comparison Of Landsat-2 And Field Spectrometer Reflectance Signatures Of South Texas Rangeland Plant Communities, Arthur J. Richardson, David E. Escobar, Harold W. Gausman, James H. Everitt

LARS Symposia

We tested the accuracy of an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the Earth Resource Technology (LANDSAT) satellite multispectral scanner (MSS) and a ground-based Exotech Model 20 spectroradiometer. The rangeland plant reflectance produced by the two sensors were correlated with no significant deviation of the slope from unity or of the intercept from zero. These results indicated that the atmospheric correction produced LANDSAT HSS estimates of rangeland plant reflectances that areas accurate as the …

Correction Of Atmospheric Effects On Landsat Data, Miguel Medina, Federico Vazquez

LARS Symposia

The Mexican Ministry of Agricultural and Water Resources, by means of the National Water Planning Commission, has applied remote sensing since 1972 to inventory land use in Mexico. The purpose of this work has been to develop the techniques which permit to eliminate the atmospheric influence on LANDSAT data and reduce them to values related with intrinsic properties of the objects of interest on earth. The result was an algorithm (SIADATM) incorporated to SIADIS system, a system of automatic interpretation of satellite images, which works in a PDP 11/70 computer. SIADATM is based on an energy conservation equation and the …

Computer Aided Hydrologic Land Use Mapping Using Satellite And Aircraft Sensed Data: Indian Case Studies, S. Thiruvengadachari

LARS Symposia

This paper presents the results of two studies on computer analysis of Landsat-derived and aircraft based multispectral scanner data towards hydrologic land use mapping, necessary for effective water resources planning and management. The analyses were performed on the interactive Multispectral Data Analysis system (MDAS) at the National Remote Sensing Agency (NRSA) headquarters in Hyderabad, India.

The first study involved automated generation of hydrologic land use information to support regional ground water exploration programmes in the Semiarid Southern parts of Tamil Nadu State in India. The accuracy of computer categorisation was estimated through stratified random sampling techniques to be around 70 …

Determination Of Potentially Arable Land And Measurements Of Non-Agricultural Uses For Nine Selected Areas In Africa, Irvin A. Goldblatt, Richard F. Hyde

LARS Symposia

The purpose of this study was to determine the percentage of total potentially arable land currently committed to non-agricultural human settlement uses in selected African agro-climatic zones.

Nine study areas equal in size to Landsat scenes, were selected by climatic zones as specified by the Food and Agriculture Organization, Rome, Italy. Soils information were fundamental to this project and were combined with climatic and crop suitability information for each study area. This information was manually converted to digital form for input to a computer-aided geographic information system, thereby creating nine independent data bases.

Landsat CCT data for these study areas …

State Of The Art Of Landsat Classification Accuracy Assessment, Russell G. Congalton, Roy A. Mead

LARS Symposia

Methods of assessing Landsat classification accuracy are necessary in order for any classification to be evaluated and improved. Continuous improvement of the ways to assess accuracy is an important key to the further use of Landsat data. Employed methods of accuracy determination and analysis will assist investigators in developing applications of Landsat imagery. The most common mans of expressing accuracy is a percentage based on the number of correctly classified pixels divided Sap the total number tallied from ground truth. This assessment is usually done as an afterthought without much regard for statistical correctness. As a result, there are no …

Multitemporal And Multispectral Remote Sensing Of Soils In Cultured Landscapes Of North Germany, J. Eckardt, J. A. Jakob, J. Lamp, V. Wittje

LARS Symposia

Different techniques have been tested since 1974 to meet the difficult task of soil remote sensing in intensively cultured and small-parcelled landscapes of North Germany.

Conventional stereo - interpretation of physiographic elements and patterns of landscapes by pan, color and infrared air photographs lowers the necessary number of soil borings and the cost of survey appreciably as well as increasing the information content and accuracy of soil maps. Especially, man-induced soil erosion and accumulation of hilly young moraines, position of sand dunes and old river beds on outwash terraces and appearance of periglacial polygon soils on flattened old moraines, only …

Inventory Estimation On The Massively Parallel Processor, Peter D. Argentiero, James P. Strong, David W. Koch

LARS Symposia

This paper describes algorithms for efficiently computing inventory estimates from satellite based images. The algorithms incorporate a one dimensional feature extraction which optimizes the pairwise sum of Fisher distances. Biases are eliminated with a premultiplication by the inverse of the analytically derived error matrix. The technique is demonstrated with a numerical example using statistics obtained from an actual LANDSAT scene.

Attention was given to implementation of the Massively Parallel processor (MPP). A timing analysis demonstrates that the inventory estimation can be performed an order of magnitude faster on the MPP than on a conventional serial machine.

Quantitative Use Of Ancillary Data In Pixel Labeling, J. A. Richards, D. A. Landgrebe, P. H. Swain

LARS Symposia

Ancillary data such as elevation, slope, rainfall, crop planting date, etc., have been recognized for some time as containing useful information for improving data analysis accuracy. However, means for incorporating data of this sort into the analysis process have seen only limited development. For example, ancillary data have been used in a more or less subjective manner in the class definition and training process and in partitioning class sets into mutually exclusive subsets. The purpose of the work reported here is to find more objective and quantitative means for using this ancillary information.

Relaxation techniques are a class of iterative …

Bulk Processing Techniques For Very Large Areas: Landsat Classification Of California, Willard Newland, David Peterson, Susan Norman

LARS Symposia

The passage of California forestry bill AB452 created a need to assess and analyze multiresource forest data on a statewide basis. The California Department of Forestry (CDF), in responding to part of this need, formed a cooperative effort with Ames Research Center (ARC) and the Jet Propulsion Laboratory (JPL) to prepare a land-cover map of the entire state, emphasizing forest types. This map was produced in less than 1 year, as required, by combining the latest techniques in digital image mosaicking at JPL with the high-speed processing capability available on the ILLIAC IV parallel processor and other computer systems at …

Remote Sensing And Land Use Planning, Paul S. T. Lee

LARS Symposia

Concern for the availability of agricultural land has prompted many states, counties and local communities to initiate programs aimed at stopping the conversion of agricultural land to other uses. Sound land use planning efforts and management programs rely upon adequate information.

In responding to the needs of timely and detailed information on changes in Land use, the U.S. Department of Agriculture and the U.S. Geological Survey have been engaged in monitoring and inventory of Land use for selected areas. In this paper, a methodological framework for monitoring changes in land use that is timely, relatively inexpensive, and appropriate for widely …

Soil Moisture Sensing With Microwave Radiometers, Thomas Schmugge

LARS Symposia

The large difference between the dielectric constant of water and dry soils produces a strong dependence of the dielectric properties, and thus emissivity, of wet soils on their moisture content in the microwave (50 > X > 1 cm) region of the electromagnetic spectrum. This change in emissivity with soil moisture content can be measured remotely with microwave radiometers. The variation of emissivity with soil moisture is dependent on the wavelength (A) of observation, soil type, surface roughness and vegetative cover. These dependencies are discussed both theoretically and experimentally. Results obtained from aircraft and spacecraft platforms are presented which give a positive …

Variability Of Reflectance Measurements With Sensor Altitude And Canopy Type, V. J. Pollara, C. S. T. Daughtry, V. C. Vanderbilt, B. F. Robinson

LARS Symposia

Reliance on portable, ground-based sensors for measuring crop reflectance has created a need for comparable and reliable measurement procedures capable of providing calibrated and reproducible canopy reflectance data. Acquisition of reproducible data is assured in part if the field of view (FOV) of the measuring sensor contains a representative sample of the canopy. The particular portion of the canopy in the sensor FOV changes with the altitude of the sensor above the canopy. For example, readings taken at low altitudes might tend to be erratic because a single leaf might fill the sensor FOV, biasing the measurements. As the sensor …

A Model Of Plant Canopy Polarization Response, V. C. Vanderbllt

LARS Technical Reports

Sensors to remotely measure the linear solarization of ground scenes have been proposed for the Multispectral Resource Sampler (MRS), a satellite sensor system proposed to compliment the Thematic Mapper. At present justification for a Sensor on MRS to measure scene polarization is limited. This paper discusses a model for the amount of linearly polarized light reflected by the shiny leaves of such crops as wheat, corn, and sorghum. The theory demonstrates that, potentially, measurements of the linearly polarized light from a crop canopy may be used as an additional feature to discriminate between crops. Examination of the model suggests that, …

Remote Sensing Of Soil Moisture Over Bare And Vegetated Fields By Microwave Radiometers, J. R. Wang, J. C. Shiue, T. J. Schmugge

LARS Symposia

Remote measurements of soil moisture contents over bare fields and fields covered with grass and soybeans were made during October 1979 with 1.4 GHz and 5 GHz microwave radiometers mounted on a mobile truck. The radiometric measurements of microwave brightness temperature TB, covered the range of incidence angles from 10° to 70° in 10° steps. The system operation was controlled by a Hewlett Packard 9835 minicomputer which also provided real-time and post-measurement data processing. Ground truth on soil moisture content, ambient air and soil temperatures was acquired concurrently with the radiometric measurements. The biomass of the vegetation was sampled about …

The Preparation Of Land Use, Land Cover, And Prime Agricultural Land Maps For Rappahannock County, Virginia, V. Cheeseman

LARS Symposia

Rural areas are now receiving more attention from planners and natural resource researchers. As existing suburban areas and new towns (including boom towns) spread across the countryside it becomes important to conduct a survey of existing land conditions. The purpose of this research was to supply geographic and statistical data on USDA defined prime farmland in an area undergoing physical development pressures.

A county-wide land use and land cover, and prime farmland inventory was performed in Rappahannock County, Virginia to study agriculturally critical areas. Individual prime farmland soil series were delineated and mapped. The objectives were to measure six characteristics …