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1

Microwave landing system autoland system analysis  

NASA Technical Reports Server (NTRS)

The objective was to investigate the ability of present day aircraft equipped with automatic flight control systems to fly advanced Microwave Landing Systems (MLS) approaches. The tactical approach used to achieve this objective included reviewing the design and autoland operation of the MD-80 aircraft, simulating the MLS approaches using a batch computer program, and assessing the performance of the autoland system from computer generated data. The results showed changes were required to present Instrument Landing System (ILS) procedures to accommodate the new MLS curved paths. It was also shown that in some cases, changes to the digital flight guidance systems would be required so that an autoland could be performed.

Feather, J. B.; Craven, B. K.

1991-01-01

2

Entry, Descent and Landing Systems Analysis Study: Phase 1 Report  

NASA Technical Reports Server (NTRS)

NASA senior management commissioned the Entry, Descent and Landing Systems Analysis (EDL-SA) Study in 2008 to identify and roadmap the Entry, Descent and Landing (EDL) technology investments that the agency needed to make in order to successfully land large payloads at Mars for both robotic and human-scale missions. This paper summarizes the motivation, approach and top-level results from Year 1 of the study, which focused on landing 10-50 mt on Mars, but also included a trade study of the best advanced parachute design for increasing the landed payloads within the EDL architecture of the Mars Science Laboratory (MSL) mission

DwyerCianciolo, Alicia M.; Davis, Jody L.; Komar, David R.; Munk, Michelle M.; Samareh, Jamshid A.; Powell, Richard W.; Shidner, Jeremy D.; Stanley, Douglas O.; Wilhite, Alan W.; Kinney, David J.; McGuire, M. Kathleen; Arnold, James O.; Howard, Austin R.; Sostaric, Ronald R.; Studak, Joseph W.; Zumwalt, Carlie H.; Llama, Eduardo G.; Casoliva, Jordi; Ivanov, Mark C.; Clark, Ian; Sengupta, Anita

2010-01-01

3

An economic systems analysis of land mobile radio telephone services  

Microsoft Academic Search

This paper deals with the economic interaction of the terrestrial and satellite land-mobile radio service systems. The cellular, trunked and satellite land-mobile systems are described. Parametric equations are formulated to allow examination of necessary user thresholds and growth rates as functions of system costs. Conversely, first order allowable systems costs are found as a function of user thresholds and growth

B. E. Leroy; S. M. Stevenson

1980-01-01

4

Data-Analysis System for Entry, Descent, and Landing  

NASA Technical Reports Server (NTRS)

A report describes the Entry Descent Landing Data Analysis (EDA), which is a system of signal-processing software and computer hardware for acquiring status data conveyed by multiple-frequency-shift-keying tone signals transmitted by a spacecraft during descent to the surface of a remote planet. The design of the EDA meets the challenge of processing weak, fluctuating signals that are Doppler-shifted by amounts that are only partly predictable. The software supports both real-time and post processing. The software performs fast-Fourier-transform integration, parallel frequency tracking with prediction, and mapping of detected tones to specific events. The use of backtrack and refinement parallel-processing threads helps to minimize data gaps. The design affords flexibility to enable division of a descent track into segments, within each of which the EDA is configured optimally for processing in the face of signal conditions and uncertainties. A dynamic-lock-state feature enables the detection of signals using minimum required computing power less when signals are steadily detected, more when signals fluctuate. At present, the hardware comprises eight dual-processor personal-computer modules and a server. The hardware is modular, making it possible to increase computing power by adding computers.

Pham, Timothy; Chang, Christine; Sartorius, Edgar; Finley, Susan; White, Leslie; Estabrook, Polly; Fort, David

2005-01-01

5

LAS - LAND ANALYSIS SYSTEM, VERSION 5.0  

NASA Technical Reports Server (NTRS)

The Land Analysis System (LAS) is an image analysis system designed to manipulate and analyze digital data in raster format and provide the user with a wide spectrum of functions and statistical tools for analysis. LAS offers these features under VMS with optional image display capabilities for IVAS and other display devices as well as the X-Windows environment. LAS provides a flexible framework for algorithm development as well as for the processing and analysis of image data. Users may choose between mouse-driven commands or the traditional command line input mode. LAS functions include supervised and unsupervised image classification, film product generation, geometric registration, image repair, radiometric correction and image statistical analysis. Data files accepted by LAS include formats such as Multi-Spectral Scanner (MSS), Thematic Mapper (TM) and Advanced Very High Resolution Radiometer (AVHRR). The enhanced geometric registration package now includes both image to image and map to map transformations. The over 200 LAS functions fall into image processing scenario categories which include: arithmetic and logical functions, data transformations, fourier transforms, geometric registration, hard copy output, image restoration, intensity transformation, multispectral and statistical analysis, file transfer, tape profiling and file management among others. Internal improvements to the LAS code have eliminated the VAX VMS dependencies and improved overall system performance. The maximum LAS image size has been increased to 20,000 lines by 20,000 samples with a maximum of 256 bands per image. The catalog management system used in earlier versions of LAS has been replaced by a more streamlined and maintenance-free method of file management. This system is not dependent on VAX/VMS and relies on file naming conventions alone to allow the use of identical LAS file names on different operating systems. While the LAS code has been improved, the original capabilities of the system have been preserved. These include maintaining associated image history, session logging, and batch, asynchronous and interactive mode of operation. The LAS application programs are integrated under version 4.1 of an interface called the Transportable Applications Executive (TAE). TAE 4.1 has four modes of user interaction: menu, direct command, tutor (or help), and dynamic tutor. In addition TAE 4.1 allows the operation of LAS functions using mouse-driven commands under the TAE-Facelift environment provided with TAE 4.1. These modes of operation allow users, from the beginner to the expert, to exercise specific application options. LAS is written in C-language and FORTRAN 77 for use with DEC VAX computers running VMS with approximately 16Mb of physical memory. This program runs under TAE 4.1. Since TAE 4.1 is not a current version of TAE, TAE 4.1 is included within the LAS distribution. Approximately 130,000 blocks (65Mb) of disk storage space are necessary to store the source code and files generated by the installation procedure for LAS and 44,000 blocks (22Mb) of disk storage space are necessary for TAE 4.1 installation. The only other dependencies for LAS are the subroutine libraries for the specific display device(s) that will be used with LAS/DMS (e.g. X-Windows and/or IVAS). The standard distribution medium for LAS is a set of two 9track 6250 BPI magnetic tapes in DEC VAX BACKUP format. It is also available on a set of two TK50 tape cartridges in DEC VAX BACKUP format. This program was developed in 1986 and last updated in 1992.

Pease, P. B.

1994-01-01

6

Overview of the NASA Entry, Descent and Landing Systems Analysis Study  

NASA Technical Reports Server (NTRS)

NASA senior management commissioned the Entry, Descent and Landing Systems Analysis (EDL-SA) Study in 2008 to identify and roadmap the Entry, Descent and Landing (EDL) technology investments that the agency needed to make in order to successfully land large payloads at Mars for both robotic and human-scale missions. This paper summarizes the approach and top-level results from Year 1 of the Study, which focused on landing 10-50 mt on Mars, but also included a trade study of the best advanced parachute design for increasing the landed payloads within the EDL architecture of the Mars Science Laboratory (MSL) mission.

Zang, Thomas A.; Dwyer-Cianciolo, Alicia M.; Kinney, David J.; Howard, Austin R.; Chen, George T.; Ivanov, Mark C.; Sostaric, Ronald R.; Westhelle, Carlos H.

2010-01-01

7

An economics systems analysis of land mobile radio telephone services  

NASA Technical Reports Server (NTRS)

The economic interaction of the terrestrial and satellite systems is considered. Parametric equations are formulated to allow examination of necessary user thresholds and growth rates as a function of system costs. Conversely, first order allowable systems costs are found as a function of user thresholds and growth rates. Transitions between satellite and terrestrial service systems are examined. User growth rate density (user/year/sq km) is shown to be a key parameter in the analysis of systems compatibility. The concept of system design matching the price/demand curves is introduced and examples are given. The role of satellite systems is critically examined and the economic conditions necessary for the introduction of satellite service are identified.

Leroy, B. E.; Stevenson, S. M.

1980-01-01

8

Entry, Descent and Landing Systems Analysis: Exploration Class Simulation Overview and Results  

NASA Technical Reports Server (NTRS)

NASA senior management commissioned the Entry, Descent and Landing Systems Analysis (EDL-SA) Study in 2008 to identify and roadmap the Entry, Descent and Landing (EDL) technology investments that the agency needed to make in order to successfully land large payloads at Mars for both robotic and exploration or human-scale missions. The year one exploration class mission activity considered technologies capable of delivering a 40-mt payload. This paper provides an overview of the exploration class mission study, including technologies considered, models developed and initial simulation results from the EDL-SA year one effort.

DwyerCianciolo, Alicia M.; Davis, Jody L.; Shidner, Jeremy D.; Powell, Richard W.

2010-01-01

9

Heave-pitch-roll analysis and testing of air cushion landing systems  

NASA Technical Reports Server (NTRS)

The analytical tools (analysis and computer simulation) needed to explain and predict the dynamic operation of air cushion landing systems (ACLS) is described. The following tasks were performed: the development of improved analytical models for the fan and the trunk; formulation of a heave pitch roll analysis for the complete ACLS; development of a general purpose computer simulation to evaluate landing and taxi performance of an ACLS equipped aircraft; and the verification and refinement of the analysis by comparison with test data obtained through lab testing of a prototype cushion. Demonstration of simulation capabilities through typical landing and taxi simulation of an ACLS aircraft are given. Initial results show that fan dynamics have a major effect on system performance. Comparison with lab test data (zero forward speed) indicates that the analysis can predict most of the key static and dynamic parameters (pressure, deflection, acceleration, etc.) within a margin of a 10 to 25 percent.

Boghani, A. B.; Captain, K. M.; Wormley, D. N.

1978-01-01

10

An economics systems analysis of land mobile radio telephone services  

Microsoft Academic Search

The economic interaction of the terrestrial and satellite systems is considered. Parametric equations are formulated to allow examination of necessary user thresholds and growth rates as a function of system costs. Conversely, first order allowable systems costs are found as a function of user thresholds and growth rates. Transitions between satellite and terrestrial service systems are examined. User growth rate

B. E. Leroy; S. M. Stevenson

1980-01-01

11

Functional Analysis of the Land-use System in Urban Residential Areas  

Microsoft Academic Search

According to Maslow's hierarchy of needs, the Sustainable Development Theory and the Theory of Urban Growth, this article which is based on the theoretical analysis of the function of the land-use system in urban residential areas has sorted out the function of it by using FAST technology and has preliminarily studied the calculation method of the functional level. This article

Liu Ling; Tan Shu-kui

2010-01-01

12

Autonomous Landing Guidance Systems  

Microsoft Academic Search

All weather tactical aircraft recovery and high sortie generation rates from forward, possibly battle damaged landing areas will reqire autonomous landing guidance systems which are independent of ground-based cooperative aids. A recently completed study has examined the operational requirements and assessed current and near term technology for an answer to this need. The Landing Systems Requirements\\/Synthesis Study has defined the

Edmond F. Roy; John W. Davison

1986-01-01

13

Land Cover Change Community-based Processing and Analysis System (LC-ComPS): Lessons Learned from Technology Infusion  

Microsoft Academic Search

The Land Cover Change Community-based Processing and Analysis System (LC-ComPS) combines grid technology, existing science modules, and dynamic workflows to enable users to complete advanced land data processing on data available from local and distributed archives. Changes in land cover represent a direct link between human activities and the global environment, and in turn affect Earth's climate. Thus characterizing land

J. Masek; A. Rao; F. Gao; P. Davis; G. Jackson; C. Huang; B. Weinstein

2008-01-01

14

Using a similarity-based algorithm within NASA Land Information System (LIS) framework for regional land surface parameter analysis over Amazonia  

Microsoft Academic Search

NASA Land Information Systems (LIS) is a framework for sophisticated land surface models capable to ingest remotely sensed and ground-based observations, such as parameters, atmospheric forcing, and data for assimilation. It produces enhanced fields of land surface states and fluxes. It has been successfully employed on land data assimilation studies LDAS (Land Data Assimilation System) at global GLDAS (Global LDAS)

L. de Goncalves; E. Rosero; L. Bastidas

2008-01-01

15

Using geographic information systems and regression analysis to evaluate relationships between land use and fecal coliform bacterial pollution  

Microsoft Academic Search

Geographic Information Systems (GIS) and regression modeling techniques were used to evaluate relationships between land use and fecal pollution in Murrells Inlet, a small, urbanized, high-salinity estuary located between Myrtle Beach and Georgetown, SC. GIS techniques were used to identify and calculate land use and spatial variables to be used in a regression model. The regression analysis was performed to

H. Kelsey; D. E. Porter; G. Scott; M. Neet; D. White

2004-01-01

16

Interfacing geographic information systems and remote sensing for rural land-use analysis  

NASA Technical Reports Server (NTRS)

Recent advances in computer-based geographic information systems (GISs) are briefly reviewed, with an emphasis on the incorporation of remote-sensing data in GISs for rural applications. Topics addressed include sampling procedures for rural land-use analyses; GIS-based mapping of agricultural land use and productivity; remote sensing of land use and agricultural, forest, rangeland, and water resources; monitoring the dynamics of irrigation agriculture; GIS methods for detecting changes in land use over time; and the development of land-use modeling strategies.

Nellis, M. Duane; Lulla, Kamlesh; Jensen, John

1990-01-01

17

Uncertainty Analysis in the Decadal Survey Era: A Hydrologic Application using the Land Information System (LIS)  

NASA Astrophysics Data System (ADS)

Computing and algorithmic advancements are making possible a more complete accounting of errors and uncertainties in earth science modeling. Knowledge of uncertainty can be critical in many application areas and can help to guide scientific research efforts. Here, we describe a plan and progress to date for a fuller accounting of hydrologic modeling uncertainties that addresses the challenges posed by decadal survey missions. These challenges include the need to account for a wide range of error sources (e.g., model error, stochastically varying inputs, observational error, downscaling) and uncertainties (model parameters, error parameters, model selection). In addition, there is a need to incorporate into an assessment all available data, which for decadal survey missions includes the wealth of data from ground, air and satellite observing systems. Our core tool is NASA’s Land Information System (LIS), a high-resolution, high-performance, land surface modeling and data assimilation system that supports a wide range of land surface research and applications. Support for parameter and uncertainty estimation was recently incorporated into the software architecture, and to date three optimization algorithms (Levenberg-Marquardt, Genetic Algorithm, and SCE-UA) and two Markov chain Monte Carlo algorithms for Bayesian analysis (random walk, Differential Evolution-Monte Carlo) have been added. Results and discussion center on a case study that was the focus of Santanello et al. (2007) who demonstrated the use of remotely sensed soil moisture for hydrologic parameter estimation in the Walnut Gulch Experimental Watershed. We contrast results from uncertainty estimation to those from parameter estimation alone. We demonstrate considerable but not complete uncertainty reduction. From this analysis, we identify remaining challenges to a more complete accounting of uncertainties.

Harrison, K.; Kumar, S.; Peters-Lidard, C. D.; Santanello, J. A.

2010-12-01

18

Decision analysis and risk models for land development affecting infrastructure systems.  

PubMed

Coordination and layering of models to identify risks in complex systems such as large-scale infrastructure of energy, water, and transportation is of current interest across application domains. Such infrastructures are increasingly vulnerable to adjacent commercial and residential land development. Land development can compromise the performance of essential infrastructure systems and increase the costs of maintaining or increasing performance. A risk-informed approach to this topic would be useful to avoid surprise, regret, and the need for costly remedies. This article develops a layering and coordination of models for risk management of land development affecting infrastructure systems. The layers are: system identification, expert elicitation, predictive modeling, comparison of investment alternatives, and implications of current decisions for future options. The modeling layers share a focus on observable factors that most contribute to volatility of land development and land use. The relevant data and expert evidence include current and forecasted growth in population and employment, conservation and preservation rules, land topography and geometries, real estate assessments, market and economic conditions, and other factors. The approach integrates to a decision framework of strategic considerations based on assessing risk, cost, and opportunity in order to prioritize needs and potential remedies that mitigate impacts of land development to the infrastructure systems. The approach is demonstrated for a 5,700-mile multimodal transportation system adjacent to 60,000 tracts of potential land development. PMID:22050390

Thekdi, Shital A; Lambert, James H

2012-07-01

19

Land system change and food security: towards multi-scale land system solutions?  

PubMed Central

Land system changes are central to the food security challenge. Land system science can contribute to sustainable solutions by an integrated analysis of land availability and the assessment of the tradeoffs associated with agricultural expansion and land use intensification. A land system perspective requires local studies of production systems to be contextualised in a regional and global context, while global assessments should be confronted with local realities. Understanding of land governance structures will help to support the development of land use policies and tenure systems that assist in designing more sustainable ways of intensification. Novel land systems should be designed that are adapted to the local context and framed within the global socio-ecological system. Such land systems should explicitly account for the role of land governance as a primary driver of land system change and food production. PMID:24143158

Verburg, Peter H; Mertz, Ole; Erb, Karl-Heinz; Haberl, Helmut; Wu, Wenbin

2013-01-01

20

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Investigation of problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars has been undertaken. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks have been under study: vehicle model design, mathematical modeling of a dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer sybsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

21

Mars Exploration Rovers Landing Dispersion Analysis  

NASA Technical Reports Server (NTRS)

Landing dispersion estimates for the Mars Exploration Rover missions were key elements in the site targeting process and in the evaluation of landing risk. This paper addresses the process and results of the landing dispersion analyses performed for both Spirit and Opportunity. The several contributors to landing dispersions (navigation and atmospheric uncertainties, spacecraft modeling, winds, and margins) are discussed, as are the analysis tools used. JPL's MarsLS program, a MATLAB-based landing dispersion visualization and statistical analysis tool, was used to calculate the probability of landing within hazardous areas. By convolving this with the probability of landing within flight system limits (in-spec landing) for each hazard area, a single overall measure of landing risk was calculated for each landing ellipse. In-spec probability contours were also generated, allowing a more synoptic view of site risks, illustrating the sensitivity to changes in landing location, and quantifying the possible consequences of anomalies such as incomplete maneuvers. Data and products required to support these analyses are described, including the landing footprints calculated by NASA Langley's POST program and JPL's AEPL program, cartographically registered base maps and hazard maps, and flight system estimates of in-spec landing probabilities for each hazard terrain type. Various factors encountered during operations, including evolving navigation estimates and changing atmospheric models, are discussed and final landing points are compared with approach estimates.

Knocke, Philip C.; Wawrzyniak, Geoffrey G.; Kennedy, Brian M.; Desai, Prasun N.; Parker, TImothy J.; Golombek, Matthew P.; Duxbury, Thomas C.; Kass, David M.

2004-01-01

22

Revised Land Use Characteristic Dataset for Asia and Southwest Asia for the Navy Aerosol Analysis and Prediction System (NAAPS)  

Microsoft Academic Search

Presently, the Navy Aerosol Analysis and Prediction System (NAAPS) uses the U.S. Geological Survey (USGS) land use characteristic dataset to determine global dust emission areas. The USGS dataset was developed from Advanced Very High-Resolution Radiometer 1-km data from April 1992 to March 1993. In the past decade drastic changes in land and water use in Asia and Southwest Asia have

A. L. Walker; K. Richardson; D. L. Westphal

2002-01-01

23

LandCaRe DSS--an interactive decision support system for climate change impact assessment and the analysis of potential agricultural land use adaptation strategies.  

PubMed

Decision support to develop viable climate change adaptation strategies for agriculture and regional land use management encompasses a wide range of options and issues. Up to now, only a few suitable tools and methods have existed for farmers and regional stakeholders that support the process of decision-making in this field. The interactive model-based spatial information and decision support system LandCaRe DSS attempts to close the existing methodical gap. This system supports interactive spatial scenario simulations, multi-ensemble and multi-model simulations at the regional scale, as well as the complex impact assessment of potential land use adaptation strategies at the local scale. The system is connected to a local geo-database and via the internet to a climate data server. LandCaRe DSS uses a multitude of scale-specific ecological impact models, which are linked in various ways. At the local scale (farm scale), biophysical models are directly coupled with a farm economy calculator. New or alternative simulation models can easily be added, thanks to the innovative architecture and design of the DSS. Scenario simulations can be conducted with a reasonable amount of effort. The interactive LandCaRe DSS prototype also offers a variety of data analysis and visualisation tools, a help system for users and a farmer information system for climate adaptation in agriculture. This paper presents the theoretical background, the conceptual framework, and the structure and methodology behind LandCaRe DSS. Scenario studies at the regional and local scale for the two Eastern German regions of Uckermark (dry lowlands, 2600 km(2)) and Weißeritz (humid mountain area, 400 km(2)) were conducted in close cooperation with stakeholders to test the functionality of the DSS prototype. The system is gradually being transformed into a web version (http://www.landcare-dss.de) to ensure the broadest possible distribution of LandCaRe DSS to the public. The system will be continuously developed, updated and used in different research projects and as a learning and knowledge-sharing tool for students. The main objective of LandCaRe DSS is to provide information on the complex long-term impacts of climate change and on potential management options for adaptation by answering "what-if" type questions. PMID:23582740

Wenkel, Karl-Otto; Berg, Michael; Mirschel, Wilfried; Wieland, Ralf; Nendel, Claas; Köstner, Barbara

2013-09-01

24

Analysis of Summer Thunderstorms in Central Alabama Using the NASA Land Information System  

NASA Technical Reports Server (NTRS)

Forecasters have difficulty predicting "random" afternoon thunderstorms during the summer months. Differences in soil characteristics could be a contributing factor for storms. The NASA Land Information System (LIS) may assist forecasters in predicting summer convection by identifying boundaries in land characteristics. This project identified case dates during the summer of 2009 by analyzing synoptic weather maps, radar, and satellite data to look for weak atmospheric forcing and disorganized convective development. Boundaries in land characteristics that may have lead to convective initiation in central Alabama were then identified using LIS.

James, Robert; Case, Jonathan; Molthan, Andrew; Jedloved, Gary

2010-01-01

25

Landing System Reliability and Safety Model.  

National Technical Information Service (NTIS)

A total systems analysis procedure for identifying the safety hazards and risks associated with the use of a defined flight control system for low visibility approach and landing (Category III) was developed. The analysis includes the ground transmitting ...

L. Fudge, L. Gephart, G. Yingling

1979-01-01

26

Space shuttle post-entry and landing analysis. Volume 1: Candidate system evaluations  

NASA Technical Reports Server (NTRS)

The general purpose of this study is to aid in the evaluation and design of multi-sensor navigation schemes proposed for the orbiter. The scope of the effort is limited to the post-entry, energy management, and approach and landing mission phases. One candidate system based on conventional navigation aids is illustrated including two DME (Distance Measuring Equipment) stations and ILS (Instrument Landing System) glide slope and localizer antennas. Some key elements of the system not shown are the onboard IMUs (Inertial Measurement Units), altimeters, and a computer. The latter is programmed to mix together (filter) the IMU data and the externally-derived data. A completely automatic, all-weather landing capability is required. Since no air-breathing engines will be carried on orbital flights, there will be no chance to go around and try again following a missed approach.

Crawford, B. S.; Duiven, E. M.

1973-01-01

27

Analysis of Summertime Convective Initiation in Central Alabama Using the Land Information System  

NASA Technical Reports Server (NTRS)

During the summer months in the southeastern United States, convective initiation presents a frequent challenge to operational forecasters. Thunderstorm development has traditionally been referred to as random due to their disorganized, sporadic appearance and lack of atmospheric forcing. Horizontal variations in land surface characteristics such as soil moisture, soil type, land and vegetation cover could possibly be a focus mechanism for afternoon convection during the summer months. The NASA Land Information System (LIS) provides a stand-alone land surface modeling framework that incorporates these varying soil and vegetation properties, antecedent precipitation, and atmospheric forcing to represent the soil state at high resolution. The use of LIS as a diagnostic tool may help forecasters to identify boundaries in land surface characteristics that could correlate to favored regions of convection initiation. The NASA Shortterm Prediction Research and Transition (SPoRT) team has been collaborating with the National Weather Service Office in Birmingham, AL to help incorporate LIS products into their operational forecasting methods. This paper highlights selected convective case dates from summer 2009 when synoptic forcing was weak, and identifies any boundaries in land surface characteristics that may have contributed to convective initiation. The LIS output depicts the effects of increased sensible heat flux from urban areas on the development of convection, as well as convection along gradients in land surface characteristics and surface sensible and latent heat fluxes. These features may promote mesoscale circulations and/or feedback processes that can either enhance or inhibit convection. With this output previously unavailable to operational forecasters, LIS provides a new tool to forecasters in order to help eliminate the randomness of summertime convective initiation.

James, Robert S.; Case, Jonathan L.; Molthan, Andrew L.; Jedlovec, Gary J.

2011-01-01

28

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

The following tasks related to the design, construction, and evaluation of a mobile planetary vehicle for unmanned exploration of Mars are discussed: (1) design and construction of a 0.5 scale dynamic vehicle; (2) mathematical modeling of vehicle dynamics; (3) experimental 0.4 scale vehicle dynamics measurements and interpretation; (4) vehicle electro-mechanical control systems; (5) remote control systems; (6) collapsibility and deployment concepts and hardware; (7) design, construction and evaluation of a wheel with increased lateral stiffness, (8) system design optimization; (9) design of an on-board computer; (10) design and construction of a laser range finder; (11) measurement of reflectivity of terrain surfaces; (12) obstacle perception by edge detection; (13) terrain modeling based on gradients; (14) laser scan systems; (15) path selection system simulation and evaluation; (16) gas chromatograph system concepts; (17) experimental chromatograph separation measurements and chromatograph model improvement and evaluation.

Frederick, D. K.; Lashmet, P. K.; Moyer, W. R.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1973-01-01

29

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Problems related to an unmanned exploration of the planet Mars by means of an autonomous roving planetary vehicle are investigated. These problems include: design, construction and evaluation of the vehicle itself and its control and operating systems. More specifically, vehicle configuration, dynamics, control, propulsion, hazard detection systems, terrain sensing and modelling, obstacle detection concepts, path selection, decision-making systems, and chemical analyses of samples are studied. Emphasis is placed on development of a vehicle capable of gathering specimens and data for an Augmented Viking Mission or to provide the basis for a Sample Return Mission.

Gisser, D. G.; Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Yerazunis, S. Y.

1975-01-01

30

Sensitivity Analysis of Land Unit Suitability for Conservation Using a Knowledge-Based System  

NASA Astrophysics Data System (ADS)

The availability of spatially continuous data layers can have a strong impact on selection of land units for conservation purposes. The suitability of ecological conditions for sustaining the targets of conservation is an important consideration in evaluating candidate conservation sites. We constructed two fuzzy logic-based knowledge bases to determine the conservation suitability of land units in the interior Columbia River basin using NetWeaver software in the Ecosystem Management Decision Support application framework. Our objective was to assess the sensitivity of suitability ratings, derived from evaluating the knowledge bases, to fuzzy logic function parameters and to the removal of data layers (land use condition, road density, disturbance regime change index, vegetation change index, land unit size, cover type size, and cover type change index). The amount and geographic distribution of suitable land polygons was most strongly altered by the removal of land use condition, road density, and land polygon size. Removal of land use condition changed suitability primarily on private or intensively-used public land. Removal of either road density or land polygon size most strongly affected suitability on higher-elevation US Forest Service land containing small-area biophysical environments. Data layers with the greatest influence differed in rank between the two knowledge bases. Our results reinforce the importance of including both biophysical and socio-economic attributes to determine the suitability of land units for conservation. The sensitivity tests provided information about knowledge base structuring and parameterization as well as prioritization for future data needs.

Humphries, Hope C.; Bourgeron, Patrick S.; Reynolds, Keith M.

2010-08-01

31

NASA Low Visibility Landing and Surface Operations (LVLASO) Atlanta Demonstration: Surveillance Systems Performance Analysis  

NASA Technical Reports Server (NTRS)

NASA conducted a series of flight experiments at Hartsfield Atlanta International Airport as part of the Low Visibility Landing and Surface Operations (LVLASO) Program. LVLASO is one of the subelements of the NASA Terminal Area Productivity (TAP) Program, which is focused on providing technology and operating procedures for achieving clear-weather airport capacity in instrument-weather conditions, while also improving safety. LVLASO is investigating various technologies to be applied to airport surface operations, including advanced flight deck displays and surveillance systems. The purpose of this report is to document the performance of the surveillance systems tested as part of the LVLASO flight experiment. There were three surveillance sensors tested: primary radar using Airport Surface Detection Equipment (ASDE-3) and the Airport Movement Area Safety System (AMASS), Multilateration using the Airport Surface Target Identification System (ATIDS), and Automatic Dependent Surveillance - Broadcast (ADS-B) operating at 1090 MHz. The performance was compared to the draft requirements of the ICAO Advanced Surface Movement Guidance and Control System (A-SMGCS). Performance parameters evaluated included coverage, position accuracy, and update rate. Each of the sensors was evaluated as a stand alone surveillance system.

Cassell, Rick; Evers, Carl; Hicok, Dan; Lee, Derrick

1999-01-01

32

Using a similarity-based algorithm within NASA Land Information System (LIS) framework for regional land surface parameter analysis over Amazonia  

NASA Astrophysics Data System (ADS)

NASA Land Information Systems (LIS) is a framework for sophisticated land surface models capable to ingest remotely sensed and ground-based observations, such as parameters, atmospheric forcing, and data for assimilation. It produces enhanced fields of land surface states and fluxes. It has been successfully employed on land data assimilation studies LDAS (Land Data Assimilation System) at global GLDAS (Global LDAS) and regional, NLDAS (North American LDAS) scales, including regions with sparse observations i.e. SALDAS (South American LDAS). Although modeling of the land surface responses to atmospheric forcing and terrain characteristics is an important tool for climate and hydrological assessment, the regional heterogeneities associated with soil and vegetation properties as well as the temporal and spatial variability of the atmospheric variables makes the applicability of such physically-based models limited. The work presented here uses LIS as a framework to improve the values of sensitive land-surface model parameters. By evaluating output using a single, multidimensional, distance-based metric, the Hausdorff norm, several fields of predictions are compared simultaneously in time and space. The metric allows us to identify parameterizations that maximize the similarity between predictions and observations. We present results of a synthetic experiment in the Large Biosphere- Atmosphere (LBA) experiment region. We show that parameter sensitivities vary within the Amazon region and that ascribing parameters based on functional groups is an effective way to address the distributed calibration problem. Additionally we discuss the issue of computational constraints in sensitivity studies and parameter estimation endeavors.

de Goncalves, L.; Rosero, E.; Bastidas, L.

2008-05-01

33

Advanced Land Imager Assessment System  

NASA Technical Reports Server (NTRS)

The Advanced Land Imager Assessment System (ALIAS) supports radiometric and geometric image processing for the Advanced Land Imager (ALI) instrument onboard NASA s Earth Observing-1 (EO-1) satellite. ALIAS consists of two processing subsystems for radiometric and geometric processing of the ALI s multispectral imagery. The radiometric processing subsystem characterizes and corrects, where possible, radiometric qualities including: coherent, impulse; and random noise; signal-to-noise ratios (SNRs); detector operability; gain; bias; saturation levels; striping and banding; and the stability of detector performance. The geometric processing subsystem and analysis capabilities support sensor alignment calibrations, sensor chip assembly (SCA)-to-SCA alignments and band-to-band alignment; and perform geodetic accuracy assessments, modulation transfer function (MTF) characterizations, and image-to-image characterizations. ALIAS also characterizes and corrects band-toband registration, and performs systematic precision and terrain correction of ALI images. This system can geometrically correct, and automatically mosaic, the SCA image strips into a seamless, map-projected image. This system provides a large database, which enables bulk trending for all ALI image data and significant instrument telemetry. Bulk trending consists of two functions: Housekeeping Processing and Bulk Radiometric Processing. The Housekeeping function pulls telemetry and temperature information from the instrument housekeeping files and writes this information to a database for trending. The Bulk Radiometric Processing function writes statistical information from the dark data acquired before and after the Earth imagery and the lamp data to the database for trending. This allows for multi-scene statistical analyses.

Chander, Gyanesh; Choate, Mike; Christopherson, Jon; Hollaren, Doug; Morfitt, Ron; Nelson, Jim; Nelson, Shar; Storey, James; Helder, Dennis; Ruggles, Tim; Kaita, Ed; Levy, Raviv; Ong, Lawrence; Markham, Brian; Schweiss, Robert

2008-01-01

34

Revised Land Use Characteristic Dataset for Asia and Southwest Asia for the Navy Aerosol Analysis and Prediction System (NAAPS)  

NASA Astrophysics Data System (ADS)

Presently, the Navy Aerosol Analysis and Prediction System (NAAPS) uses the U.S. Geological Survey (USGS) land use characteristic dataset to determine global dust emission areas. The USGS dataset was developed from Advanced Very High-Resolution Radiometer 1-km data from April 1992 to March 1993. In the past decade drastic changes in land and water use in Asia and Southwest Asia have quickly outdated this dataset. In China and Mongolia, age-old practices of farming and animal husbandry have been abandoned. Herders have too many animals in one location allowing the grassland to be eaten away and leaving vast areas of topsoil exposed and primed for removal by the wind. In the case of Southwest Asia, a four-year drought is in progress. Many of the wetlands and marshes in the river deltas are drying up from the lack of water runoff. To compound the problem several new dams were and are being built along the major watersheds. In particular, Iraq's dam building in the 1990's and politically driven draining of the Mesopotamian marshes between the Tigris and Euphrates rivers has lead to the near disappearance of this historical marshland. To incorporate these changes we are updating the USGS land use characteristic dataset using GIS-like software named ENVI (Environment for Visualizing Images), 1 km National Geophysical Data Center (NGDC) global topographical data, satellite imagery, and recently released governmental maps and reports. (For example, within the last two years the Chinese and Mongolian governments have released land degradation and desertification maps to satisfy the requirements set forth by United Nations Convention to Combat Desertification.) The steps taken to create the new land use characteristic database will be described in detail. Before (non-dust producing areas) and after (dust producing areas) examples will be shown.

Walker, A. L.; Richardson, K.; Westphal, D. L.

2002-12-01

35

Agricultural drought analysis and famine early warning with the FEWS NET land data assimilation system  

NASA Astrophysics Data System (ADS)

Global and regional changes related to water resources and agriculture affect food and fresh water security. To mitigate and adapt to these changes it is important to quantify how climate variability and change has impacted agricultural production and water resources. This research examines trends in supply and demand for moisture availability in rain-fed agro-pastoral regions. With a focus on the Sahel region of Africa we ask the following two questions: (1) Do land surface models, forced with remotely sensed data, detect the spatio-temporal patterns of agricultural drought over the past 30 years? (2) How have these trends impacted agricultural productivity and food security? To explore implications of hydro-climatic (e.g. precipitation and potential evapotranspiration (PET)) change on agriculture, we use the Famine Early Warning Systems Network Land Data Assimilation System (FLDAS) forced with rainfall from the University of California Santa Barbara Climate Hazards Infrared-Precipitation with Stations (CHIRPS) dataset (1981-present) and 10 km meteorological data (wind, temperature, radiation, humidity) from Cheney and Sheffield, released in 2012, for continental Africa north of 10S (1979-2008). We examine trends in model outputs (e.g. soil moisture and evapotranspiration (ET)), as well as composite indices, such at the evapotranspiration-rainfall ratio and water requirement satisfaction index (WRSI). We compare these results to the Normalized Difference Vegetation Index (NDVI) and microwave soil moisture. Finally, we examine how the different model outputs and composite indices relate to reported trends in agricultural production. Preliminary results show that the FLDAS Noah3.2 and geoWRSI models accurately estimate near surface (0-40cm) soil moisture anomalies as defined by microwave and in-situ observations across the Sahel. With respect to ET, the literature reports that vegetation biomass, as indicated by NDVI, has increased in conjunction with rainfall (i.e. ';re-greening' of the Sahel). However, at least one study has reported a downward trend in modeled ET in the Sahel. Preliminary results indicate that the spatial and temporal patterns of transpiration in Noah3.2 and geoWRSI are highly sensitive to their respective vegetation parameterizations. Our model runs explore the timing and magnitude of ';crop' vegetation parameters, such as LAI and green vegetation fraction, to assess agricultural drought trends and confirm findings from previous work.

McNally, A.; Shukla, S.; Funk, C. C.; Husak, G. J.; Arsenault, K. R.; Peters-Lidard, C. D.; Verdin, J. P.

2013-12-01

36

Dual Heat Pulse, Dual Layer Thermal Protection System Sizing Analysis and Trade Studies for Human Mars Entry Descent and Landing  

NASA Technical Reports Server (NTRS)

NASA has been recently updating design reference missions for the human exploration of Mars and evaluating the technology investments required to do so. The first of these started in January 2007 and developed the Mars Design Reference Architecture 5.0 (DRA5). As part of DRA5, Thermal Protection System (TPS) sizing analysis was performed on a mid L/D rigid aeroshell undergoing a dual heat pulse (aerocapture and atmospheric entry) trajectory. The DRA5 TPS subteam determined that using traditional monolithic ablator systems would be mass expensive. They proposed a new dual-layer TPS concept utilizing an ablator atop a low thermal conductivity insulative substrate to address the issue. Using existing thermal response models for an ablator and insulative tile, preliminary hand analysis of the dual layer concept at a few key heating points indicated that the concept showed potential to reduce TPS masses and warranted further study. In FY09, the followon Entry, Descent and Landing Systems Analysis (EDL-SA) project continued by focusing on Exploration-class cargo or crewed missions requiring 10 to 50 metric tons of landed payload. The TPS subteam advanced the preliminary dual-layer TPS analysis by developing a new process and updated TPS sizing code to rapidly evaluate mass-optimized, full body sizing for a dual layer TPS that is capable of dual heat pulse performance. This paper describes the process and presents the results of the EDL-SA FY09 dual-layer TPS analyses on the rigid mid L/D aeroshell. Additionally, several trade studies were conducted with the sizing code to evaluate the impact of various design factors, assumptions and margins.

McGuire, Mary Kathleen

2011-01-01

37

The Land Gini Coefficient and Its Application for Land Use Structure Analysis in China  

PubMed Central

We introduce the Gini coefficient to assess the rationality of land use structure. The rapid transformation of land use in China provides a typical case for land use structure analysis. In this study, a land Gini coefficient (LGC) analysis tool was developed. The land use structure rationality was analyzed and evaluated based on statistical data for China between 1996 and 2008. The results show: (1)The LGC of three major land use types–farmland, built-up land and unused land–was smaller when the four economic districts were considered as assessment units instead of the provinces. Therefore, the LGC is spatially dependent; if the calculation unit expands, then the LGC decreases, and this relationship does not change with time. Additionally, land use activities in different provinces of a single district differed greatly. (2) At the national level, the LGC of the three main land use types indicated that during the 13 years analyzed, the farmland and unused land were evenly distributed across China. However, the built-up land distribution was relatively or absolutely unequal and highlights the rapid urbanization in China. (3) Trends in the distribution of the three major land use types are very different. At the national level, when using a district as the calculation unit, the LGC of the three main land use types increased, and their distribution became increasingly concentrated. However, when a province was used as the calculation unit, the LGC of the farmland increased, while the LGC of the built-up and unused land decreased. These findings indicate that the distribution of the farmland became increasingly concentrated, while the built-up land and unused land became increasingly uniform. (4) The LGC analysis method of land use structure based on geographic information systems (GIS) is flexible and convenient. PMID:24130764

Zheng, Xinqi; Xia, Tian; Yang, Xin; Yuan, Tao; Hu, Yecui

2013-01-01

38

Information analysis of a spatial database for ecological land classification  

NASA Technical Reports Server (NTRS)

An ecological land classification was developed for a complex region in southern California using geographic information system techniques of map overlay and contingency table analysis. Land classes were identified by mutual information analysis of vegetation pattern in relation to other mapped environmental variables. The analysis was weakened by map errors, especially errors in the digital elevation data. Nevertheless, the resulting land classification was ecologically reasonable and performed well when tested with higher quality data from the region.

Davis, Frank W.; Dozier, Jeff

1990-01-01

39

The Global Land Data Assimilation System  

Microsoft Academic Search

A Global Land Data Assimilation System (GLDAS) has been developed. Its purpose is to ingest satellite- and ground-based observational data products, using advanced land surface modeling and data assimilation techniques, in order to generate optimal fields of land surface states and fluxes. GLDAS is unique in that it is an uncoupled land surface modeling system that drives multiple models, integrates

M. Rodell; U. Jambor; J. Gottschalck; K. Mitchell; C.-J. Meng; K. Arsenault; B. Cosgrove; J. Radakovich; M. Bosilovich; J. K. Entin; J. P. Walker; D. Lohmann; D. Toll

2004-01-01

40

A SYSTEMIC APPROACH TO MITIGATING URBAN STORM WATER RUNOFF VIA DEVELOPMENT PLANS BASED ON LAND SUITABILITY ANALYSIS  

EPA Science Inventory

We advocate an approach to reduce the anticipated increase in stormwater runoff from conventional development by demonstrating a low-impact development that incorporates hydrologic factors into an expanded land suitability analysis. This methodology was applied to a 3 hectare exp...

41

LAND USE, COVER AND FORMS CLASSIFICATION SYSTEM  

E-print Network

FLORIDA LAND USE, COVER AND FORMS CLASSIFICATION SYSTEM HANDBOOK JANUARY 1999 DEPARTMENT CLASSIFICATION SYSTEM FLORIDA DEPARTMENT OF TRANSPORTATION SURVEYING AND MAPPING OFFICE GEOGRPAHIC MAPPING LAND USE, COVER AND FORMS CLASSIFICATION SYSTEM ABOUT THIS EDITION: This is an updated FLORIDA LAND USE

Binford, Michael W.

42

Autonomous landing guidance system validation  

NASA Astrophysics Data System (ADS)

ALG is a combination of raster imaging sensor, head-up displays, flight guidance and procedures which allow pilots to perform hand flown aircraft maneuvers in adverse weather, at night, or in low visibility conditions at facilities with minimal or no ground aids. Maneuvers in the context of ALG relate to takeoff, landing, rollout, taxi and terminal parking. Commercial needs are driven by potential revenue savings since today only 43 Type III and 80 Type II instrumented landing system (ILS) runway ends in the United States are equipped for lower minimum flight operations. Additionally, most of these ILS facilities are clustered at major gateway airports which further impacts on dispatch authority and general ATC regional delays. Infrastructure consists to upgrade additional runways must not only account for the high integrity ground instrumentation, but also the installation of lights and markers mandated for Cat III operations. The military services ability to train under realistic battlefield conditions, to project power globally in support of national interests, while providing humanitarian aid, is significantly impaired by the inability to conduct precision approaches and landings in low visibility conditions to either instrumented runways or to a more tactical environment with operations into and out of unprepared landing strips, particularly when time does not permit deployment of ground aids and the verification of their integrity. Recently, Lear Astronics, in cooperation with Consortium members of the ALG Program, concluded a flight test program which evaluated the utility of the ALG system in meeting both civil and military needs. Those results are the subject of this paper.

Bui, Long Q.; Franklin, Michael R.; Taylor, Christopher; Neilson, Graham

1997-06-01

43

Land mobile satellite system requirements  

NASA Technical Reports Server (NTRS)

A Land Mobile Satellite System (LMSS) provides voice, data and related communications services to moving vehicles and persons. Communications between the mobiles and satellite are in the 806-890 MHz band. The satellite translates these signals to a ""fixed services band'' such as 14/12 GHz band (Ku-band), and communicates in this band with fixed terminals called gateways. The gateways are located at convenient places such as telephone switches (which provide entry into the national telephone system), dispatcher headquarters, computer centers, etc. Communications are therefore principally mobile to fixed. A third communications link, also at Ku-band, is needed between the satellite and a single fixed ground station. This link provides satellite command, telemetry and ranging and also provides a network control function. The latter, through a common signalling system, receives requests and assigns channel slots, and otherwise controls, monitors and polices the network and collects billing information.

Kiesling, J. D.

1983-01-01

44

Land mobile satellite system requirements  

NASA Astrophysics Data System (ADS)

A Land Mobile Satellite System (LMSS) provides voice, data and related communications services to moving vehicles and persons. Communications between the mobiles and satellite are in the 806-890 MHz band. The satellite translates these signals to a ""fixed services band'' such as 14/12 GHz band (Ku-band), and communicates in this band with fixed terminals called gateways. The gateways are located at convenient places such as telephone switches (which provide entry into the national telephone system), dispatcher headquarters, computer centers, etc. Communications are therefore principally mobile to fixed. A third communications link, also at Ku-band, is needed between the satellite and a single fixed ground station. This link provides satellite command, telemetry and ranging and also provides a network control function. The latter, through a common signalling system, receives requests and assigns channel slots, and otherwise controls, monitors and polices the network and collects billing information.

Kiesling, J. D.

1983-05-01

45

Analysis of Landing-Gear Behavior  

NASA Technical Reports Server (NTRS)

This report presents a theoretical study of the behavior of the conventional type of oleo-pneumatic landing gear during the process of landing impact. The basic analysis is presented in a general form and treats the motions of the landing gear prior to and subsequent to the beginning of shock-strut deflection. The applicability of the analysis to actual landing gears has been investigated for the particular case of a vertical landing gear in the absence of drag loads by comparing calculated results with experimental drop-test data for impacts with and without tire bottoming. The calculated behavior of the landing gear was found to be in good agreement with the drop-test data.

Milwitzky, Benjamin; Cook, Francis E

1953-01-01

46

MOLDOVA LAND TENURE SYSTEM Carlton A Brown  

E-print Network

MOLDOVA LAND TENURE SYSTEM Carlton A Brown May 2002 1. Introduction 1.1. The Moldova land tenure are encountered. A compromise between both agencies and the government of Moldova has created a cadastral system of Moldova as well as a discussion of the USAID cadastral system and the World Bank cadastral system. Next

Onsrud, Harlan J.

47

Sensitivity Analysis in Agent-Based Models of Socio-Ecological Systems: An Example in Agricultural Land Conservation for Lake Water Quality Improvement  

NASA Astrophysics Data System (ADS)

Socio-ecological systems are dynamic and nonlinear. To account for this complexity, we employ agent-based models (ABMs) to study macro-scale phenomena resulting from micro-scale interactions among system components. Because ABMs typically have many parameters, it is challenging to identify which parameters contribute to the emerging macro-scale patterns. In this paper, we address the following question: What is the extent of participation in agricultural land conservation programs given heterogeneous landscape, economic, social, and individual decision making criteria in complex lakesheds? To answer this question, we: [1] built an ABM for our model system; [2] simulated land use change resulting from agent decision making, [3] estimated the uncertainty of the model output, decomposed it and apportioned it to each of the parameters in the model. Our model system is a freshwater socio-ecological system - that of farmland and lake water quality within a region containing a large number of lakes and high proportions of agricultural lands. Our study focuses on examining how agricultural land conversion from active to fallow reduces freshwater nutrient loading and improves water quality. Consequently, our ABM is composed of farmer agents who make decisions related to participation in a government-sponsored Conservation Reserve Program (CRP) managed by the Farm Service Agency (FSA). We also include an FSA agent, who selects enrollment offers made by farmers and announces the signup results leading to land use change. The model is executed in a Monte Carlo simulation framework to generate a distribution of maps of fallow lands that are used for calculating nutrient loading to lakes. What follows is a variance-based sensitivity analysis of the results. We compute sensitivity indices for individual parameters and their combinations, allowing for identification of the most influential as well as the insignificant inputs. In the case study, we observe that farmland conservation is first and foremost driven by the FSA signup choices. Environmental criteria used in FSA offer selection play a secondary role in farmland-to-fallow-land conversion. Farmer decision making is mainly influenced by the willingness to reduce the potential annual rental payments. As the case study demonstrates, our approach leads to ABM simplification without the loss of outcome variability. It also shows how to represent the magnitude of ABM complexity and isolate the effects of the interconnected explanatory variables on the simulated emergent phenomena. More importantly, the results of our research indicate that some of the parameters exert influence on model outcomes only if analyzed in combination with other parameters. Without evaluating the interaction effects among inputs, we risk losing important functional relationships among ABM components and, consequently, we potentially reduce its explanatory power.

Ligmann-Zielinska, A.; Kramer, D. B.; Spence Cheruvelil, K.; Soranno, P.

2012-12-01

48

Application of tire dynamics to aircraft landing gear design analysis  

NASA Technical Reports Server (NTRS)

The tire plays a key part in many analyses used for design of aircraft landing gear. Examples include structural design of wheels, landing gear shimmy, brake whirl, chatter and squeal, complex combination of chatter and shimmy on main landing gear (MLG) systems, anti-skid performance, gear walk, and rough terrain loads and performance. Tire parameters needed in the various analyses are discussed. Two tire models are discussed for shimmy analysis, the modified Moreland approach and the von Schlippe-Dietrich approach. It is shown that the Moreland model can be derived from the Von Schlippe-Dietrich model by certain approximations. The remaining analysis areas are discussed in general terms and the tire parameters needed for each are identified. Accurate tire data allows more accurate design analysis and the correct prediction of dynamic performance of aircraft landing gear.

Black, R. J.

1983-01-01

49

Techniques of UAV system land use changes detection application  

NASA Astrophysics Data System (ADS)

The unmanned aerial vehicle( UAV) was able to acquire remote sensing images with low cost, precise and high spatial resolution information needed by management of Land use at desired time. The aim of this paper was to present an overview of the ongoing research on the potential and techniques of low-altitude UAV system for land use applications. The development of crucial subsystems consisting of the UAV platforms, multiple camera system, camera calibration and photogrammetric production, was introduced together. A procedure of images acquisition and photogrammetric processing was proposed. To detect land use changes, methods based on DSMs and DLG were discussed and adopted in this paper. Finally, analysis of land use research based UAVs was realized on real flight experiments of two study areas. The results of this study show that UAVs can be used successfully for land use change detection.

Zhang, Youying; Cui, Hongxia

2011-02-01

50

Flight test evaluation of the E-systems Differential GPS category 3 automatic landing system  

NASA Technical Reports Server (NTRS)

Test flights were conducted to evaluate the capability of Differential Global Positioning System (DGPS) to provide the accuracy and integrity required for International Civil Aviation Organization (ICAO) Category (CAT) III precision approach and landings. These test flights were part of a Federal Aviation Administration (FAA) program to evaluate the technical feasibility of using DGPS based technology for CAT III precision approach and landing applications. An IAI Westwind 1124 aircraft (N24RH) was equipped with DGPS receiving equipment and additional computing capability provided by E-Systems. The test flights were conducted at NASA Ames Research Center's Crows Landing Flight Facility, Crows Landing, California. The flight test evaluation was based on completing 100 approaches and landings. The navigation sensor error accuracy requirements were based on ICAO requirements for the Microwave Landing System (MLS). All of the approaches and landings were evaluated against ground truth reference data provided by a laser tracker. Analysis of these approaches and landings shows that the E-Systems DGPS system met the navigation sensor error requirements for a successful approach and landing 98 out of 100 approaches and landings, based on the requirements specified in the FAA CAT III Level 2 Flight Test Plan. In addition, the E-Systems DGPS system met the integrity requirements for a successful approach and landing or stationary trial for all 100 approaches and landings and all ten stationary trials, based on the requirements specified in the FAA CAT III Level 2 Flight Test Plan.

Kaufmann, David N.; Mcnally, B. David

1995-01-01

51

A land based radar polarimeter processing system  

E-print Network

A LAND BASED RADAR POLARIMETER PROCESSING SYSTEM A Thesis by CHESTER WILLIAM KRONKE Submitted to the Graduate College of Texas AAM University in Partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1984 Major... Member M. J. McFarland Member W. B. Jones Head of Department May 1984 ABSTRACT A Land Based Radar Polarimeter Processor System. (May 1984) Chester William Kronke, B. S. , Texas ABM University Chairman of Advisory Committee: Dr. A. J. Blanchard...

Kronke, Chester William

2012-06-07

52

An analysis of Milwaukee county land use  

NASA Technical Reports Server (NTRS)

The identification and classification of urban and suburban phenomena through analysis of remotely-acquired sensor data can provide information of great potential value to many regional analysts. Such classifications, particularly those using spectral data obtained from satellites such as the first Earth Resources Technology Satellite (ERTS-1) orbited by NASA, allow rapid frequent and accurate general land use inventories that are of value in many types of spatial analyses. In this study, Milwaukee County, Wisconsin was classified into several broad land use categories on the basis of computer analysis of four bands of ERTS spectral data (ERTS Frame Number E1017-16093). Categories identified were: (1) road-central business district, (2) grass (green vegetation), (3) suburban, (4) wooded suburb, (5) heavy industry, (6) inner city, and (7) water. Overall, 90 percent accuracy was attained in classification of these urban land use categories.

Todd, W. J.; Mausel, P. E.

1973-01-01

53

Crew procedures for microwave landing system operations  

NASA Technical Reports Server (NTRS)

The objective of this study was to identify crew procedures involved in Microwave Landing System (MLS) operations and to obtain a preliminary assessment of crew workload. The crew procedures were identified for three different complements of airborne equipment coupled to an autopilot. Using these three equipment complements, crew tasks were identified for MLS approaches and precision departures and compared to an ILS approach and a normal departure. Workload comparisons between the approaches and departures were made by using a task-timeline analysis program that obtained workload indexes, i.e., the radio of time required to complete the tasks to the time available. The results showed an increase in workload for the MLS scenario for one of the equipment complements. However, even this workload was within the capacity of two crew members.

Summers, Leland G.

1987-01-01

54

78 FR 23491 - National Forest System Land Management Planning; Correction  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land Management Planning; Correction AGENCY: Forest...revising, and monitoring land management plans (the planning rule). The National Forest...National Forest System Land Management Planning Rule Final...

2013-04-19

55

An Interpretation System for Land Register Maps  

Microsoft Academic Search

A system for the automatic acquisition of land register maps is described. The system converts paper-based documents into digital form for integration into an existing database. Processing a map begins with its digitization by a scanning device. A key step in the system is the conversion from raster format to graph representation, a special binary image format suitable for processing

Luca Boatto; Vincenzo Consorti; Monica Del Buono; Silvano Di Zenzo; Vincenzo Eramo; Alessandra Esposito; Francesco Melcarne; Marco Mosciatti; Andrea Morelli; Stefano Scarci; Marco Tucci

1992-01-01

56

Title : "SMALL Savannah: An Information System for the integrated analysis of land use change in the Far North Cameroon"  

E-print Network

integrated, participatory and trans-disciplinary approach to reduce land degradation, biodiversity loss productivity and loss of biodiversity. With increasing population, climate change risk and regular human in this thesis indicates that the accessibility to the main urban centre of the region, soil suitability

Hille, Sander

57

Inertial navigation system for mobile land vehicles  

Microsoft Academic Search

This paper describes a prototype of an inertial navigation system for use in mobile land vehicles, such as cars or mobile robots. The complete system is composed by sensors, their mechanical mount and cabling, these connect to a PC card with local processing and memory, based on a Intel 80C196KC microcontroller. The sensors used were a piezoelectric vibrating gyroscope, two

Jorge Lobo; Paulo Lucas; Jorge Dias; A. Traca de Almeida

1995-01-01

58

A comparative analysis of the Global Land Cover 2000 and MODIS land cover data sets  

USGS Publications Warehouse

Accurate and up-to-date global land cover data sets are necessary for various global change research studies including climate change, biodiversity conservation, ecosystem assessment, and environmental modeling. In recent years, substantial advancement has been achieved in generating such data products. Yet, we are far from producing geospatially consistent high-quality data at an operational level. We compared the recently available Global Land Cover 2000 (GLC-2000) and MODerate resolution Imaging Spectrometer (MODIS) global land cover data to evaluate the similarities and differences in methodologies and results, and to identify areas of spatial agreement and disagreement. These two global land cover data sets were prepared using different data sources, classification systems, and methodologies, but using the same spatial resolution (i.e., 1 km) satellite data. Our analysis shows a general agreement at the class aggregate level except for savannas/shrublands, and wetlands. The disagreement, however, increases when comparing detailed land cover classes. Similarly, percent agreement between the two data sets was found to be highly variable among biomes. The identified areas of spatial agreement and disagreement will be useful for both data producers and users. Data producers may use the areas of spatial agreement for training area selection and pay special attention to areas of disagreement for further improvement in future land cover characterization and mapping. Users can conveniently use the findings in the areas of agreement, whereas users might need to verify the informaiton in the areas of disagreement with the help of secondary information. Learning from past experience and building on the existing infrastructure (e.g., regional networks), further research is necessary to (1) reduce ambiguity in land cover definitions, (2) increase availability of improved spatial, spectral, radiometric, and geometric resolution satellite data, and (3) develop advanced classification algorithms. ?? 2004 Elsevier Inc. All rights reserved.

Giri, C.; Zhu, Z.; Reed, B.

2005-01-01

59

Validation and Verification of Operational Land Analysis Activities at the Air Force Weather Agency  

NASA Technical Reports Server (NTRS)

The NASA developed Land Information System (LIS) is the Air Force Weather Agency's (AFWA) operational Land Data Assimilation System (LDAS) combining real time precipitation observations and analyses, global forecast model data, vegetation, terrain, and soil parameters with the community Noah land surface model, along with other hydrology module options, to generate profile analyses of global soil moisture, soil temperature, and other important land surface characteristics. (1) A range of satellite data products and surface observations used to generate the land analysis products (2) Global, 1/4 deg spatial resolution (3) Model analysis generated at 3 hours

Shaw, Michael; Kumar, Sujay V.; Peters-Lidard, Christa D.; Cetola, Jeffrey

2011-01-01

60

Apollo experience report: Earth landing system  

NASA Technical Reports Server (NTRS)

A brief discussion of the development of the Apollo earth landing system and a functional description of the system are presented in this report. The more significant problems that were encountered during the program, the solutions, and, in general, the knowledge that was gained are discussed in detail. Two appendixes presenting a detailed description of the various system components and a summary of the development and the qualification test programs are included.

West, R. B.

1973-01-01

61

Spectroradiometric considerations for advanced land observing systems  

NASA Technical Reports Server (NTRS)

Research aimed at improving the inflight absolute radiometric calibration of advanced land observing systems was initiated. Emphasis was on the satellite sensor calibration program at White Sands. Topics addressed include: absolute radiometric calibration of advanced remote sensing; atmospheric effects on reflected radiation; inflight radiometric calibration; field radiometric methods for reflectance and atmospheric measurement; and calibration of field relectance radiometers.

Slater, P. N.

1986-01-01

62

Research priorities in land use and land-cover change for the Earth system and integrated assessment modelling  

E-print Network

). Copyright ? 2010 Royal Meteorological Society and Crown Copyright. KEY WORDS land use; land cover; Earth system models; integrated assessment models; research priorities Received 12 January 2009; Revised 9 March 2010; Accepted 14 March 2010 1. Introduction 1... biogeophysical, socio- economic and human decision-making perspectives. The Earth System Modeling (ESM) and the Integrated Assessment Modeling (IAM) communities play an impor- tant role in understanding and quantifying Earth system analysis and, specifically...

Hibbard, Kathy; Janetos, Anthony; van Vuuren, Detlef P.; Pongtatz, Julia; Rose, Steven K.; Betts, Richard; Herold, Martin; Feddema, Johannes J.

2010-01-01

63

LAND SYSTEMS AS SURROGATES FOR BIODIVERSITY IN CONSERVATION PLANNING  

Microsoft Academic Search

Environmental surrogates (land classes) for the distribution of biodiversity are increasingly being used for conservation planning. However, data that demonstrate coincident patterns in land classes and biodiversity are limited. We ask the overall question, ''Are land systems effective surrogates for the spatial configuration of biodiversity for conservation planning?'' and we address three specific questions: (1) Do different land systems represent

Ian Oliver; Andrew Holmes; J. Mark Dangerfield; Michael Gillings; Anthony J. Pik; David R. Britton; Marita Holley; Margaret E. Montgomery; Madeline Raison; Vicki Logan; Robert L. Pressey; Andrew J. Beattie

2004-01-01

64

Biofuels, land and water : a systems approach to sustainability.  

SciTech Connect

There is a strong societal need to evaluate and understand the sustainability of biofuels, especially because of the significant increases in production mandated by many countries, including the United States. Sustainability will be a strong factor in the regulatory environment and investments in biofuels. Biomass feedstock production is an important contributor to environmental, social, and economic impacts from biofuels. This study presents a systems approach where the agricultural, energy, and environmental sectors are considered as components of a single system, and environmental liabilities are used as recoverable resources for biomass feedstock production. We focus on efficient use of land and water resources. We conducted a spatial analysis evaluating marginal land and degraded water resources to improve feedstock productivity with concomitant environmental restoration for the state of Nebraska. Results indicate that utilizing marginal land resources such as riparian and roadway buffer strips, brownfield sites, and marginal agricultural land could produce enough feedstocks to meet a maximum of 22% of the energy requirements of the state compared to the current supply of 2%. Degraded water resources such as nitrate-contaminated groundwater and wastewater were evaluated as sources of nutrients and water to improve feedstock productivity. Spatial overlap between degraded water and marginal land resources was found to be as high as 96% and could maintain sustainable feedstock production on marginal lands. Other benefits of implementing this strategy include feedstock intensification to decrease biomass transportation costs, restoration of contaminated water resources, and mitigation of greenhouse gas emissions.

Gopalakrishnan, G.; Negri, M. C.; Wang, M.; Wu, M.; Snyder, S. W.; LaFreniere, L.

2009-08-01

65

A land mobile satellite data system  

NASA Technical Reports Server (NTRS)

The Telesat Mobile Incorporated (TMI) Mobile Data System (MDS) was developed to apply satellite technology to the transportation industry's requirement for a fleet management system. It will provide two-way messaging and automatic position reporting capabilities between dispatch centers and customers' fleets of trucks. The design was based on the Inmarsat L-Band space segment with system link parameters and margins adjusted to meet the land mobile satellite channel characteristics. The system interfaces with the Teleglobe Des Laurentides earth station at Weir, Quebec. The signaling protocols were derived from the Inmarsat Standard C packet signalling system with unique trucking requirements incorporated where necessary.

Kent, John D. B.

1990-01-01

66

The Sand Land Soil System and Society  

NASA Astrophysics Data System (ADS)

Worldwide arid soils such as Latterites from African Savannas to the Xeralfs and Xererts of the Mediterranean Basin Ortents and Orthids of Asian Deserts are uniquely different in their strategic roles for utilizing the land in places where a delicate balance between annual climatic cycles and general trends toward desertification predominate Arid lands cover 1 3 of global land surface and contain irreplaceable natural resources with potential productivity of meeting the demands of more than two billion people and serving as sources and sinks of atmospheric CO2 to combat global warming The soil system in these arid areas are being degraded underutilized and kept in a stage of obliviousness due to inadequate public literacy and most importantly in-sufficient scientific evaluations based on pedology and soil taxonomy standards Implementation of food security projects and sustainable development programs on randomly selected sites and assessment of land degradation worldwide by powerful computers and satellite imagery techniques without field work and identification of Representative Soil Units are data producing and grant attracting but counter productive We live in a world in which there is an order out there and things are precisely measured and categorized for efficient utilization Why not the soils mainly in arid areas How we could generalize the world of soils under our feet by concept of soils are the same Expansion of educational programs quantification of multiple ecosystems within the arid regions through detailed and correlated

Mahjoory, R. A.

67

Video guidance, landing, and imaging systems  

NASA Technical Reports Server (NTRS)

The adaptive potential of video guidance technology for earth orbital and interplanetary missions was explored. The application of video acquisition, pointing, tracking, and navigation technology was considered to three primary missions: planetary landing, earth resources satellite, and spacecraft rendezvous and docking. It was found that an imaging system can be mechanized to provide a spacecraft or satellite with a considerable amount of adaptability with respect to its environment. It also provides a level of autonomy essential to many future missions and enhances their data gathering ability. The feasibility of an autonomous video guidance system capable of observing a planetary surface during terminal descent and selecting the most acceptable landing site was successfully demonstrated in the laboratory. The techniques developed for acquisition, pointing, and tracking show promise for recognizing and tracking coastlines, rivers, and other constituents of interest. Routines were written and checked for rendezvous, docking, and station-keeping functions.

Schappell, R. T.; Knickerbocker, R. L.; Tietz, J. C.; Grant, C.; Rice, R. B.; Moog, R. D.

1975-01-01

68

Landing Characteristics of a Re-entry Vehicle with a Passive Landing System for Impact Alleviation  

NASA Technical Reports Server (NTRS)

Landing Characteristics of a Re-entry Vehicle with a Passive Landing System for Impact Alleviation. An experimental investigation was made to determine the landing characteristics of a 1/8-scale dynamic model of a reentry vehicle using a passive landing system to alleviate the landing-impact loads. The passive landing system consisted of a flexible heat shield with a small section of aluminum honeycomb placed between the heat shield and the crew compartment at the point that would be the first to contact the landing surface. The model was landed on concrete and sand landing surfaces at parachute letdown velocities. The investigations simulated a vertical velocity of 30 ft/sec (full scale), horizontal velocities of 0, 15, 30, 40, and 50 ft/sec (full scale), and landing attitudes ranging from -30 degrees to 20 degrees. The model investigation indicated that stable landings could be made on a concrete surface at horizontal velocities up to about 30 ft/sec, but the stable landing-attitude range at these speeds was small. The aluminum honeycomb bottomed occasionally during landings on concrete. When bottoming did not occur, maximum normal and longitudinal accelerations at the center of gravity of the vehicle were approximately 50g and 30g, respectively. [Entire movie available on DVD from CASI as Doc ID 20070030981. Contact help@sti.nasa.gov

1963-01-01

69

Land value tax in the context of sustainable urban development and assessment. Part i ? policy analysis and conceptual model for the taxation system on real property  

Microsoft Academic Search

This article on issues related to real property taxes has two parts. Part One deliberates the concept of sustainable development as well as Lithuania's real property taxation system and possible ways to improve it. Part Two analyses various methods of land assessment. The objectives of this paper are to analyze the importance of a tax on real property within the

Saulius Raslanas; Edmundas Kazimieras Zavadskas; Art?ras Kaklauskas

2010-01-01

70

Guide to NASA's Pilot Land Data System (PLDS).  

National Technical Information Service (NTIS)

NASA's Pilot Land Data System (PLDS) is a distributed information management system designed to support NASA's land science community. The PLDS provides a wide range of services including management of information about scientific data, access to a librar...

1991-01-01

71

Feasibility Analysis of Aircraft Landing Scheduling for Non-Controlled Airports  

E-print Network

airports Air traffic control automation system development Trajectory analysis Aircraft landing schedulingFeasibility Analysis of Aircraft Landing Scheduling for Non-Controlled Airports AIAA-2004-5241 Yuanyuan Ding, Jie Rong, and John Valasek Aerospace Engineering AIAA Guidance, Navigation, and Control

Valasek, John

72

The Auto-Tuned Land Data Assimilation System (ATLAS)  

NASA Astrophysics Data System (ADS)

Land data assimilation systems are commonly tasked with merging remotely sensed surface soil moisture retrievals with information derived from a soil water balance model driven by observed rainfall. The performance of such systems can be degraded by the incorrect specification of parameters describing modeling and observation errors. Here the Auto-Tuned Land Data Assimilation System (ATLAS) is introduced to simultaneously solve for all parameters required for the application of a simple land data assimilation system to integrate satellite-based rainfall and soil moisture retrievals for drought monitoring applications. The approach is based on combining a triple collocation (TC) strategy with the statistical analysis of filtering innovations and designed to leverage the simultaneous availability of satellite-based soil moisture products acquired from both active and passive microwave remote sensing. A number of variants of the ATLAS approach—each based on a different strategy for leveraging TC and innovation analysis within an adaptive filtering framework—are derived and evaluated through a synthetic twin experiment. In addition, a preliminary real data analysis is conducted using actual satellite-based products and evaluated against independent ground-based observations. Results illustrate the potential of ATLAS to improve the analysis of soil moisture anomalies using data products derived from the Global Precipitation Measurement (GPM) and the NASA Soil Moisture Active/Passive missions.

Crow, W. T.; Yilmaz, M. Tugrul

2014-01-01

73

Spatiotemporal analysis of land use and land cover change in the Brazilian Amazon  

PubMed Central

This paper provides a comparative analysis of land use and land cover (LULC) changes among three study areas with different biophysical environments in the Brazilian Amazon at multiple scales, from per-pixel, polygon, census sector, to study area. Landsat images acquired in the years of 1990/1991, 1999/2000, and 2008/2010 were used to examine LULC change trajectories with the post-classification comparison approach. A classification system composed of six classes – forest, savanna, other-vegetation (secondary succession and plantations), agro-pasture, impervious surface, and water, was designed for this study. A hierarchical-based classification method was used to classify Landsat images into thematic maps. This research shows different spatiotemporal change patterns, composition and rates among the three study areas and indicates the importance of analyzing LULC change at multiple scales. The LULC change analysis over time for entire study areas provides an overall picture of change trends, but detailed change trajectories and their spatial distributions can be better examined at a per-pixel scale. The LULC change at the polygon scale provides the information of the changes in patch sizes over time, while the LULC change at census sector scale gives new insights on how human-induced activities (e.g., urban expansion, roads, and land use history) affect LULC change patterns and rates. This research indicates the necessity to implement change detection at multiple scales for better understanding the mechanisms of LULC change patterns and rates. PMID:24127130

Li, Guiying; Moran, Emilio; Hetrick, Scott

2013-01-01

74

Human Planetary Landing System (HPLS) Capability Roadmap NRC Progress Review  

NASA Technical Reports Server (NTRS)

Capability Roadmap Team. Capability Description, Scope and Capability Breakdown Structure. Benefits of the HPLS. Roadmap Process and Approach. Current State-of-the-Art, Assumptions and Key Requirements. Top Level HPLS Roadmap. Capability Presentations by Leads. Mission Drivers Requirements. "AEDL" System Engineering. Communication & Navigation Systems. Hypersonic Systems. Super to Subsonic Decelerator Systems. Terminal Descent and Landing Systems. A Priori In-Situ Mars Observations. AEDL Analysis, Test and Validation Infrastructure. Capability Technical Challenges. Capability Connection Points to other Roadmaps/Crosswalks. Summary of Top Level Capability. Forward Work.

Manning, Rob; Schmitt, Harrison H.; Graves, Claude

2005-01-01

75

Louisiana comprehensive planning information system. [computerized land use mapping system  

NASA Technical Reports Server (NTRS)

A statewide computerized land use mapping system is reported that uses polygons to identify inventories from aerial photography by employing the USGS classification system. In addition, the system provides soil, population, and housing census data as well as economic indicators that can be useful in relating to the overall system.

Ryan, P. W.; Schwertz, E.

1975-01-01

76

Valuing agricultural land standard prices based on agricultural land gradation and evaluation information system (ALGEIS)  

NASA Astrophysics Data System (ADS)

Agriculture land is the most fundamental material of production, and is man's indispensable living condition for existence. Agricultural land prices reflect not only the uses of agricultural land, but the potential uses as well. This paper reviews the valuation on agricultural land prices in western developed countries and the development courses of agricultural land appraisal, especially valuation on agricultural land standard prices in China. The problems in the valuation at present are analyzed. According to the thinking of "first gradating and then evaluating," "Agriculture Land Gradation and Evaluation Information System" (ALGEIS) based on Geographical Information Systems (GIS) is developed. As a case study, the proposed method is applied to value agricultural land standard prices in Yunan County, Guangdong Province, China. The case study shows that the proposed method is a practical and satisfactory one. The applications of achievements of valuation on agricultural land prices are discussed, which effectively promote the reform and development of land resources administration. Developing agriculture land gradation and evaluation information system based on GIS, can satisfy spatial, dynamic, quantitive and comprehensive requests in valuation on agriculture land.

Liu, Yaolin; Wang, Kun; Liu, Yanfang; Deng, Nianchao; Liu, Yang

2008-10-01

77

Land use changes and its impact on land surface temperature of Yancheng City from 2000 to 2009 analysis  

NASA Astrophysics Data System (ADS)

In the paper, based on the technology of remote sensing and geographic information system, and according to the Landsat TM images obtained the land use database and land surface temperature of Yancheng city in the year of 2000 and 2009. Five land use types were identified, namely: farmland, building site, forest and grassland, water, and beach wetland. And then analysis of the urban expansion model based on the Defense Meteorological satellite data. The results show that: (1) In the five kinds of land use types, the largest rate of land use change is beach wetland, which is -8.23, followed by water as -5.17, forest and grassland is 3.27, building site is 2.24, farmland is 0.69. (2) During the 2000-2009, the towns of Yancheng city continuous outward expansion. In the old town, the expansion model is similar to the concentric circles spread to the periphery, but in the new district, which mainly concentrated in the northeast and southeast, the expansion model is re-planning, development and construction. (3) The land use structure change, especially the changes of beach wetland have a largest influence on the land surface temperature of Yancheng city. Among them, the average land surface temperature has increased over 8 degrees. However, the farmland change due to the overall land surface temperature decreased. And the increase of building site, making the urban heat island effect has been enhanced, while the town where the land surface temperature increases in value added in 0 to 5 degrees. At the same time, the water changes, this due to the land surface temperature increases and the added value in the range of 5 to 8 degrees.

Wang, Xinghan

2014-02-01

78

AGFATL- ACTIVE GEAR FLEXIBLE AIRCRAFT TAKEOFF AND LANDING ANALYSIS  

NASA Technical Reports Server (NTRS)

The Active Gear, Flexible Aircraft Takeoff and Landing Analysis program, AGFATL, was developed to provide a complete simulation of the aircraft takeoff and landing dynamics problem. AGFATL can represent an airplane either as a rigid body with six degrees of freedom or as a flexible body with multiple degrees of freedom. The airframe flexibility is represented by the superposition of up to twenty free vibration modes on the rigid-body motions. The analysis includes maneuver logic and autopilots programmed to control the aircraft during glide slope, flare, landing, and takeoff. The program is modular so that performance of the aircraft in flight and during landing and ground maneuvers can be studied separately or in combination. A program restart capability is included in AGFATL. Effects simulated in the AGFATL program include: (1) flexible aircraft control and performance during glide slope, flare, landing roll, and takeoff roll under conditions of changing winds, engine failures, brake failures, control system failures, strut failures, restrictions due to runway length, and control variable limits and time lags; (2) landing gear loads and dynamics for up to five gears; (3) single and multiple engines (maximum of four) including selective engine reversing and failure; (4) drag chute and spoiler effects; (5) wheel braking (including skid-control) and selective brake failure; (6) aerodynamic ground effects; (7) aircraft carrier operations; (8) inclined runways and runway perturbations; (9) flexible or rigid airframes; 10) rudder and nose gear steering; and 11) actively controlled landing gear shock struts. Input to the AGFATL program includes data which describe runway roughness; vehicle geometry, flexibility and aerodynamic characteristics; landing gear(s); propulsion; and initial conditions such as attitude, attitude change rates, and velocities. AGFATL performs a time integration of the equations of motion and outputs comprehensive information on the airframe, state-of-maneuver logic, autopilots, control response, and aircraft loads from impact, runway roll-out, and ground operations. Flexible-body and total (elastic plus rigid-body) displacements, velocities, and accelerations are also output in the flexible-body option for up to twenty points on the aircraft. The AGFATL program is written in FORTRAN IV for batch execution and has been implemented on a CDC CYBER 170 series computer with an overlayed central memory requirement of approximately 141 (octal) of 60 bit words. The AGFATL program was last updated in 1984.

Mcgehee, J. R.

1994-01-01

79

Analysis of land use and land cover change in a coastal area of Rio de Janeiro using  

E-print Network

opportunities, but require intensive resource management and environmental protection. Land use and land cover interaction areas between the land and the ocean, suffer from intense human activity and can quickly become1 Analysis of land use and land cover change in a coastal area of Rio de Janeiro using high

80

Analysis of Land Suitable for Algae State of Hawaii  

E-print Network

. Increased demand for biofuels has increased interest in growing algae in Hawaii for biofuels. An analysisAnalysis of Land Suitable for Algae Production State of Hawaii Prepared for the U.S. Department agency thereof. #12;Analysis of Land Suitable for Algae Production State of Hawaii Prepared by Mele

81

Airplane takeoff and landing performance monitoring system  

NASA Technical Reports Server (NTRS)

The invention is a real-time takeoff and landing performance monitoring system for an aircraft which provides a pilot with graphic and metric information to assist in decisions related to achieving rotation speed (VR) within the safe zone of a runway, or stopping the aircraft on the runway after landing or take-off abort. The system processes information in two segments: a pretakeoff segment and a real-time segment. One-time inputs of ambient conditions and airplane configuration information are used in the pretakeoff segment to generate scheduled performance data. The real-time segment uses the scheduled performance data, runway length data and transducer measured parameters to monitor the performance of the airplane throughout the takeoff roll. Airplane acceleration and engine-performance anomalies are detected and annunciated. A novel and important feature of this segment is that it updates the estimated runway rolling friction coefficient. Airplane performance predictions also reflect changes in head wind occurring as the takeoff roll progresses. The system provides a head-down display and a head-up display. The head-up display is projected onto a partially reflective transparent surface through which the pilot views the runway. By comparing the present performance of the airplane with a continually predicted nominal performance based upon given conditions, performance deficiencies are detected by the system and conveyed to pilot in form of both elemental information and integrated information.

Middleton, David B. (inventor); Srivatsan, Raghavachari (inventor); Person, Lee H., Jr. (inventor)

1994-01-01

82

Inferring Land Surface Model Parameters for the Assimilation of Satellite-Based L-Band Brightness Temperature Observations into a Soil Moisture Analysis System  

NASA Technical Reports Server (NTRS)

The Soil Moisture and Ocean Salinity (SMOS) satellite mission provides global measurements of L-band brightness temperatures at horizontal and vertical polarization and a variety of incidence angles that are sensitive to moisture and temperature conditions in the top few centimeters of the soil. These L-band observations can therefore be assimilated into a land surface model to obtain surface and root zone soil moisture estimates. As part of the observation operator, such an assimilation system requires a radiative transfer model (RTM) that converts geophysical fields (including soil moisture and soil temperature) into modeled L-band brightness temperatures. At the global scale, the RTM parameters and the climatological soil moisture conditions are still poorly known. Using look-up tables from the literature to estimate the RTM parameters usually results in modeled L-band brightness temperatures that are strongly biased against the SMOS observations, with biases varying regionally and seasonally. Such biases must be addressed within the land data assimilation system. In this presentation, the estimation of the RTM parameters is discussed for the NASA GEOS-5 land data assimilation system, which is based on the ensemble Kalman filter (EnKF) and the Catchment land surface model. In the GEOS-5 land data assimilation system, soil moisture and brightness temperature biases are addressed in three stages. First, the global soil properties and soil hydraulic parameters that are used in the Catchment model were revised to minimize the bias in the modeled soil moisture, as verified against available in situ soil moisture measurements. Second, key parameters of the "tau-omega" RTM were calibrated prior to data assimilation using an objective function that minimizes the climatological differences between the modeled L-band brightness temperatures and the corresponding SMOS observations. Calibrated parameters include soil roughness parameters, vegetation structure parameters, and the single scattering albedo. After this climatological calibration, the modeling system can provide L-band brightness temperatures with a global mean absolute bias of less than 10K against SMOS observations, across multiple incidence angles and for horizontal and vertical polarization. Third, seasonal and regional variations in the residual biases are addressed by estimating the vegetation optical depth through state augmentation during the assimilation of the L-band brightness temperatures. This strategy, tested here with SMOS data, is part of the baseline approach for the Level 4 Surface and Root Zone Soil Moisture data product from the planned Soil Moisture Active Passive (SMAP) satellite mission.

Reichle, Rolf H.; De Lannoy, Gabrielle J. M.

2012-01-01

83

Comparison analysis of agricultural land gradation evaluation based on different weight making methods  

NASA Astrophysics Data System (ADS)

Agricultural land gradation links land classification and land appraisal. It indicates the difference in agricultural productivity resulted from differences in land's natural characteristics and/or the effectiveness and efficiency of agricultural production at present and in the future. Technically, agricultural land is graded based on the sum of weighted indices and further classified by equal-distance, or axis, or sum frequency curve. It is critical to define the system of weights in this process. In practice, a single or mixed weight system has been widely applied in agricultural land gradation. However, few studies put efforts in comparing outcomes in applying different systems of weights for a specific area. This research applied several popular systems of weights, such as AHP, factor analysis, grey relation analysis, entropy method, and etc., in gradating agricultural land in Jintan, Jiangsu province. Outcomes resulted from different systems of weights were compared. The result did illustrate the obvious differences among these outcomes, which in turn stood for differences among systems of weights. Considering biases inherent in different systems of weights, a system of combined weights is highly recommended for the general practice in agricultural land gradation.

Jin, Xiaobin; Zhang, Honghui; Zhou, Yinkang

2008-10-01

84

Constellation Program (CxP) Crew Exploration Vehicle (CEV) Project Integrated Landing System  

NASA Technical Reports Server (NTRS)

Crew Exploration Vehicle (CEV) Chief Engineer requested a risk comparison of the Integrated Landing System design developed by NASA and the design developed by Contractor- referred to as the LM 604 baseline. Based on the results of this risk comparison, the CEV Chief engineer requested that the NESC evaluate identified risks and develop strategies for their reduction or mitigation. The assessment progressed in two phases. A brief Phase I analysis was performed by the Water versus Land-Landing Team to compare the CEV Integrated Landing System proposed by the Contractor against the NASA TS-LRS001 baseline with respect to risk. A phase II effort examined the areas of critical importance to the overall landing risk, evaluating risk to the crew and to the CEV Crew Module (CM) during a nominal land-landing. The findings of the assessment are contained in this report.

Baker, John D.; Yuchnovicz, Daniel E.; Eisenman, David J.; Peer, Scott G.; Fasanella, Edward L.; Lawrence, Charles

2009-01-01

85

77 FR 2563 - Public Land Order No. 7787; Withdrawal of Public and National Forest System Lands in the Grand...  

Federal Register 2010, 2011, 2012, 2013

...DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLAZ91000.L14300000.ET0000.LXSIURAM0000, AZA 35138] Public Land Order No. 7787; Withdrawal of Public and National Forest System Lands in the Grand Canyon Watershed;...

2012-01-18

86

Validation and Verification of Operational Land Analysis Activities at the Air Force Weather Agency  

NASA Technical Reports Server (NTRS)

The NASA developed Land Information System (LIS) is the Air Force Weather Agency's (AFWA) operational Land Data Assimilation System (LDAS) combining real time precipitation observations and analyses, global forecast model data, vegetation, terrain, and soil parameters with the community Noah land surface model, along with other hydrology module options, to generate profile analyses of global soil moisture, soil temperature, and other important land surface characteristics. (1) A range of satellite data products and surface observations used to generate the land analysis products (2) Global, 1/4 deg spatial resolution (3) Model analysis generated at 3 hours. AFWA recognizes the importance of operational benchmarking and uncertainty characterization for land surface modeling and is developing standard methods, software, and metrics to verify and/or validate LIS output products. To facilitate this and other needs for land analysis activities at AFWA, the Model Evaluation Toolkit (MET) -- a joint product of the National Center for Atmospheric Research Developmental Testbed Center (NCAR DTC), AFWA, and the user community -- and the Land surface Verification Toolkit (LVT), developed at the Goddard Space Flight Center (GSFC), have been adapted to operational benchmarking needs of AFWA's land characterization activities.

Shaw, Michael; Kumar, Sujay V.; Peters-Lidard, Christa D.; Cetola, Jeffrey

2012-01-01

87

Extensible Modular Landing Systems for Human Moon and Mars Exploration  

E-print Network

Extensible Modular Landing Systems for Human Moon and Mars Exploration by Wilfried Hofstetter and Proposed Moon and Mars Exploration System architectures...... 27 2.1.1 The Apollo System...................................................................................... 54 3. Moon and Mars System Architectures Point Designs

de Weck, Olivier L.

88

Mars Exploration Rovers Entry, Descent, and Landing Trajectory Analysis  

NASA Technical Reports Server (NTRS)

The Mars Exploration Rover mission successfully landed two rovers "Spirit" and "Opportunity" on Mars on January 4th and 25th of 2004, respectively. The trajectory analysis performed to define the entry, descent, and landing (EDL) scenario is described. The entry requirements and constraints are presented, as well as uncertainties used in a Monte Carlo dispersion analysis to statistically assess the robustness of the entry design to off-nominal conditions. In the analysis, six-degree-of-freedom and three-degree-of-freedom trajectory results are compared to assess the entry characteristics of the capsule. Comparison of the preentry results to preliminary post-landing reconstruction data shows that all EDL parameters were within the requirements. In addition, the final landing position for both "Spirit" and "Opportunity" were within 15 km of the predicted landing location.

Desai, Prasun N.; Knocke, Philip C.

2004-01-01

89

Land Cover Analysis of Temperate Asia  

NASA Technical Reports Server (NTRS)

Satellite data from the advanced very high resolution radiometer (AVHRR) instrument were used to produce a general land cover distribution of temperate Asia (referred to hence as Central Asia) from 1982, starting with the NOAA-7 satellite, and continuing through 1991, ending with the NOAA-11 satellite. Emphasis was placed upon delineating the and and semi-arid zones of Central Asia (largely Mongolia and adjacent areas), mapping broad categories of aggregated land cover, and upon studying photosynthetic capacity increases in Central Asia from 1982 to 1991.

Justice, Chris

1998-01-01

90

Policy implications in developing a land use management information systems  

NASA Technical Reports Server (NTRS)

The current land use map for the city of Los Angeles was developed by the guesstimation process and provides single stage information for each level in the critical geographical hierarchy for land use planning management. Processing and incorporation of LANDSAT data in the land use information system requires special funding; however, computergraphic maps are able to provide a viable information system for city planning and management.

Landini, A. J.

1975-01-01

91

The effects of war on land-use/land-cover change: An analysis of Landsat imagery for northeast Bosnia  

NASA Astrophysics Data System (ADS)

The use of satellite technology by military planners has a relatively long history as a tool of warfare, but little research has used satellite technology to study the effects of war. This research addresses this gap by applying satellite remote sensing imagery to study the effects of war on land-use/land-cover change in northeast Bosnia. The war in Bosnia, 1992-1995, resulted in over 100,000 deaths, many more wounded, and the mass displacement of nearly half the population of 4.2 million. When combined with the destruction of much of the transportation infrastructure and housing stock, widespread mine placement, and loss of agricultural machinery, the impacts to both the people and land were dramatic. Though the most severe war impacts are visible at local scales (e.g. destroyed buildings), this study focuses on impacts to agricultural land, a larger scale visible to satellite sensors. Multispectral Landsat Thematic Mapper (TM) data (30m pixels) from before and during the war in addition to recent imagery from 2004/05 were used to detect abandoned agricultural land. The satellite images were co-registered to enable a perpixel analysis of changes based on the statistical properties of the pixels using multiple change detection methods. Ground reference data were collected in May of 2006 at survey sites selected using a stratified random sampling approach based on the derived map of abandoned agricultural land. Fine resolution (60cm) Quickbird imagery was also used to verify the accuracy of the classification. The remote sensing analysis results were then used to test two hypotheses related to war outcomes: (a) land abandonment is due to wartime minefields and (b) land abandonment is greater in pre-war Croat areas and areas where ethnic cleansing was heaviest. The effects of minefields on land abandonment was first tested in a geographic information system (GIS), and then by using multiple regression models that account for spatial autocorrelation among observations. The spatial regression analysis was conducted at the opstina (county) areal unit and used minefield locations, refugee returns and population change data as predictors of abandoned agricultural land. Results from these analyses show that a supervised classification of the Landsat TM data identified abandoned agricultural land with an overall accuracy of 82.5%. The GIS and spatial regression analysis of how war affects agricultural land showed that the presence of minefields and population declines are both associated with abandoned agricultural land. This research holds significance for both the remote sensing and civil war research communities. The use of freely available Quickbird imagery both as training data for the supervised classifier and as supplementary ground reference data suggest these methods are applicable to other civil wars (e.g. Darfur region of Sudan and the Horn of Africa) that may still be too dangerous for researchers to conduct field work in. By extending these methods to other war zones, comparisons of similarities and differences between such studies can then be made to draw broader conclusions of war impacts to land use and land cover.

Witmer, Frank D. W.

92

Analysis, Suppression of Land Clutter Characteristics Reported.  

National Technical Information Service (NTIS)

The properties of land clutter and target echo of the ground combat surveillance radar are presented. The mathematical model for the clutter power spectrum and the relationship between the cutoff frequency of the clutter spectrum and the wind speed are ob...

F. Wang, X. Zhang

1987-01-01

93

Analysis of the densification of reclaimed surface mined land  

E-print Network

ANALYSIS OF THE DENSIFICATION OF RECLAIMED SURFACE MINED LAND A Thesis by WILLIAM JOSEPH SCHNEIDER Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May... 1977 Major Subject: Geology ANALYSIS OF THE DENSIFICATION OF RECLAIMED SURFACED MINED LAND A Thesis WILLIAM JOSEPH SCHNEIDER Approved as to style and content by: (Chairman of Committee) (Head of Department) (Member) Member) May 1977 cgQ$ 7'g...

Schneider, William Joseph

2012-06-07

94

Flight tests of the Digital Integrated Automatic Landing System (DIALS)  

NASA Technical Reports Server (NTRS)

The design, development, implementation and flight tests of the Digital Integrated Automatic Landing System (DIALS) are discussed. The system was implemented and flight tested on the Transport Systems Research Vehicle (TSRV), a Boeing 737-100. The design uses modern optimal control methods. The direct digital design obtained uses a 10 Hz rate for the sampling of sensors and the control commands. The basic structure of the control law consists of a steady state Kalman filter followed by a control gain matrix. The sensor information used includes Microwave Landing System (MLS) position, attitude, calibrated airspeed, and body accelerations. The phases of the final approach considered are localized and steep glideslope capture (which may be performed simultaneously or independently), localizer and glideslope track, crab/decrab, and flare to touchdown. The system can capture, track, and flare from conventional, as well as steep, glideslopes ranging from 2.5 deg to 5.5 deg. All of the modes of the control law including the Kalman filters were implemented on the TSRV flight computers which use fixed point arithmetic with 16 bit words. The implementation considerations are described as well as an analysis of the flight test results.

Halyo, N.

1984-01-01

95

Analysis of land use and cover change in Sichuan province, China  

NASA Astrophysics Data System (ADS)

A series of environmental policies in Sichuan province was executed to restore the grassland and forestland on some degraded lands after 2000. But the effectiveness on land use and cover change (LUCC) has not yet been systematically investigated. We undertook a detailed analysis about land use and cover change between 2000 and 2005 in Sichuan province. Our study mainly utilized remotely sensed data of 2005 China-Brazil Earth Resources Satellite II (CBERS II) and 2000 Landsat 5 thematic mapper (TM) data. Land use and cover change between 2000 and 2005 was visually interpreted by CBERS II with ArcInfo Workstation based on land use and cover database interpreted from TM. Then LUCC was validated by ground truth with global positioning system receivers. Our analysis illustrates that the conservation policies to restore the grassland and forestland were successful to a lesser extent. But more measures to restore the grassland and forestland of Sichuan province have to be taken further in the future.

Zheng, Zezhong; Yang, Wunian; Zhou, Guoqing; Wang, Xiaoting

2012-01-01

96

Sustainable Eco-Systems under Land Retirement  

E-print Network

the soil water salinity also affects the leaching efficiencysoil water salinity as a result of land retirement and or annual leachingsoil water retention increased, thereby decreasing the amount of water available for leaching.

Wallender, Wesley W.

2009-01-01

97

REMOTE SENSING ANALYSIS OF LAND COVER CHANGE  

Microsoft Academic Search

In Australia, remotely sensed Landsat data is routinely used for mapping and monitoring changes in the extent of woody perennial vegetation. Time series remotely sensed satellite imagery and ground information is used to form multi-temporal classifications of presence\\/absence of woody cover. Two broad-scale operational land cover change and monitoring projects are based on a series of algorithms and methods developed

X. Wu; P. Caccetta; S. Furby; J. Wallace; M. Zhu; WG VII

98

Impacts of Current and Previous Land Use on Greenhouse Gas Fluxes for Biofuel Cropping Systems  

NASA Astrophysics Data System (ADS)

Biofuel cropping systems are both a source and sink of greenhouse gases (GHG). Fertilizer and pesticide manufacture and transport, farm machinery operation, and processing of biomass into fuel all lead to carbon dioxide (CO2) emissions, but the largest GHG sources for biofuel systems are often soil nitrous oxide (N2O) emissions and loss of organic carbon as a result of land use change. However, improved land management can increase soil carbon levels and decrease N2O emissions, thus complementing the CO2 sink from displaced fossil fuel combustion. Previously cropped land, grazed land, and Conservation Reserve Program (CRP) land is being converted to biofuel cropping. We report results for the central US because most of the land used for biofuel cropping is in the central region of the country (corn/soy belt). The primary tool for this analysis is the DAYCENT ecosystem model. The ability of the model to simulate soil GHG fluxes and crop yields is demonstrated and results from simulations of different land management scenarios are presented. Our analyses suggest that conversion of CRP or grazed land to corn ethanol cropping under conventional management leads to a net source of GHG, but that converting these lands to perennial cellulosic biofuel cropping results in a GHG sink. Previously cropped land converted to corn ethanol under conventional management is a small GHG sink, but improved management and conversion to cellulosic based crops can greatly increase this sink strength.

Del Grosso, S.; Parton, W.; Adler, P.; Ogle, S.; West, T.

2008-12-01

99

A Meta-Analysis of Global Urban Land Expansion  

PubMed Central

The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km2 from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km2 and 12,568,000 km2, with an estimate of 1,527,000 km2 more likely. PMID:21876770

Seto, Karen C.; Fragkias, Michail; Guneralp, Burak; Reilly, Michael K.

2011-01-01

100

Analysis of human spatial perception during lunar landing  

E-print Network

Crewed lunar landings require astronauts to interact with automated systems to identify a location that is level and free of hazards and to guide the vehicle to the lunar surface through a controlled descent. However, ...

Clark, Torin K.

101

LanguageLand : a multimodal conversational spoken language learning system  

E-print Network

LanguageLand is a multimodal conversational spoken language learning system whose purpose is to help native English users learn Mandarin Chinese. The system is centered on a game that involves navigation on a simulated ...

Lee, Vivienne C. (Vivienne Catherine)

2004-01-01

102

Shipboard Operational Evaluation of Carrier Landing Aid Stabilization System.  

National Technical Information Service (NTIS)

A prototype Carrier Landing Aid Stabilization System (CLASS) has undergone two shipboard operational evaluations. CLASS operation was compared to the current FLOLS MK6 Mod 1 Stabilization system. Review of the test data reveals CLASS provides significantl...

W. F. Davis

1971-01-01

103

SANITARY SEWER SYSTEMS - LAND APPLICATION AREAS, NEUSE RIVER WATERSHED, NC  

EPA Science Inventory

The North Carolina Rural Economic Development Center (NCREDC) in conjunction with Hobbs, Upchurch & Associates developed the digital Sewer system land applications as mapped by individual system owners as required by contract. The data collected will facilitate planning, siting a...

104

Pollution sources identification in the "land-sea" system.  

PubMed

It is our opinion that the new scientific thinking and education in the 21st century will increase the significance of the multidisciplinary nature knowledge. The nature of the marine sediments as well as the biochemical features of the littoral organisms appear to be in close relation to the geochemical impact of the coastal onshore. The biogeochemical analysis of the terrestrial and marine biocenosis is still fragmental, without balance between the casual and sequential relationships. Along the Bulgarian Black Sea coast the latter necessitates the geological pattern clarification of the areas south of Bourgas. Even a superficial overview of the geological features of the region highlights the impact of the geochemical anomalies related to Rosen and Zidarovo volcanic apparatuses and intrusions, other ore deposits south and south-west as well. However, the intensive anthropogenic impact on the geochemical haloes should be pointed out in the complex of ecological damage to the coast. Through complementary geoecological studies a significant updating of the knowledge is suggested. The geoecological mapping is needed to present the ratio of the lands saturated with geonoxes, and anthropogenically polluted ones. The new methodology recommended was applied to make the distinction of such lands in the regions of Pirdop and Kardjali. Another key element appears to be the ecological-economic characteristics in the offshore-onshore balance. The marine resources will be studied in the alternative context: benefit-damage from the onshore polluters, and the biogeochemical characteristics of the littoral zone. The coastal area's environmental status should make a distinction between the environmentally undamaged, environmentally damaged by nature, anthropogenically damaged and complex damaged lands. Each ecological study or analysis presenting the ecological condition of the environment in a status quo (at a certain moment and at a certain location) is described in this work as a Status Geoecological System. For environmental management and protection of the Black Sea we refer to an indispensable Data File representing the Dynamic Geoecological System. PMID:12420965

Dachev, D; Zlatanova, S

2002-01-01

105

Biologically inspired enhanced vision system (EVS) for aircraft landing guidance  

Microsoft Academic Search

A useful enhanced vision system (EVS) for aircraft landing guidance not only has to provide the pilots a reliable image of the scene by fusing several sensor images in real time, but should also give them additional information such as attitude, navigation and hazard signals for safe landing in all weather conditions. Here, a biologically inspired EVS is proposed. The

Chiu Hung Luk; Changjian Gao; Dan Hammerstrom; M. Pavel; D. Kerr

2004-01-01

106

GEOGRAPHIC INFORMATION SYSTEMS CENTER FOR ENVIRONMENTAL MANAGEMENT OF MILITARY LANDS  

E-print Network

GEOGRAPHIC INFORMATION SYSTEMS CENTER FOR ENVIRONMENTAL MANAGEMENT OF MILITARY LANDS CEMML | 1490 and efficient decision making, planning, and management of military training lands. GIS provides a spatial be customized for an installation to incorporate its military mission objectives, address operational scheduling

107

Designing a System for Land Change Science Meta-Study  

E-print Network

Designing a System for Land Change Science Meta-Study Abstract In this work-in-progress paper, we to support meta- analyses of global environmental change. Using data from a workshop on the state-of-the-art of meta-study in the land change science research community, we highlight the limitations of current

Ellis, Erle C.

108

Land use planning and early warning systems for limiting drought  

E-print Network

Land use planning and early warning systems for limiting drought impacts and promoting recovery J-term agroecological potential? 3a. Land use plans: what/how to produce + drought response plan 1a. Soil + climate maps 2b. What is current status relative to potential (ecosystem health/soil quality)? 4. Drought

109

Post2 End-to-End Descent and Landing Simulation for ALHAT Design Analysis Cycle 2  

NASA Technical Reports Server (NTRS)

The ALHAT project is an agency-level program involving NASA centers, academia, and industry, with a primary goal to develop a safe, autonomous, precision-landing system for robotic and crew-piloted lunar and planetary descent vehicles. POST2 is used as the 6DOF descent and landing trajectory simulation for determining integrated system performance of ALHAT landing-system models and lunar environment models. This paper presents updates in the development of the ALHAT POST2 simulation, as well as preliminary system performance analysis for ALDAC-2 used for the testing and assessment of ALHAT system models. The ALDAC-2 POST2 Monte Carlo simulation results have been generated and focus on HRN model performance with the fully integrated system, as well performance improvements of AGNC and TSAR model since the previous design analysis cycle

Davis, Jody L.; Striepe, Scott A.; Maddock, Robert W.; Johnson, Andrew E.; Paschall, Stephen C., II

2010-01-01

110

Online Time Series Analysis of Land Products over Asia Monsoon Region via Giovanni  

NASA Technical Reports Server (NTRS)

Time series analysis is critical to the study of land cover/land use changes and climate. Time series studies at local-to-regional scales require higher spatial resolution, such as 1km or less, data. MODIS land products of 250m to 1km resolution enable such studies. However, such MODIS land data files are distributed in 10ox10o tiles, due to large data volumes. Conducting a time series study requires downloading all tiles that include the study area for the time period of interest, and mosaicking the tiles spatially. This can be an extremely time-consuming process. In support of the Monsoon Asia Integrated Regional Study (MAIRS) program, NASA GES DISC (Goddard Earth Sciences Data and Information Services Center) has processed MODIS land products at 1 km resolution over the Asia monsoon region (0o-60oN, 60o-150oE) with a common data structure and format. The processed data have been integrated into the Giovanni system (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) that enables users to explore, analyze, and download data over an area and time period of interest easily. Currently, the following regional MODIS land products are available in Giovanni: 8-day 1km land surface temperature and active fire, monthly 1km vegetation index, and yearly 0.05o, 500m land cover types. More data will be added in the near future. By combining atmospheric and oceanic data products in the Giovanni system, it is possible to do further analyses of environmental and climate changes associated with the land, ocean, and atmosphere. This presentation demonstrates exploring land products in the Giovanni system with sample case scenarios.

Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina

2011-01-01

111

Preliminary analysis of knee stress in Full Extension Landing  

PubMed Central

OBJECTIVE: This study provides an experimental and finite element analysis of knee-joint structure during extended-knee landing based on the extracted impact force, and it numerically identifies the contact pressure, stress distribution and possibility of bone-to-bone contact when a subject lands from a safe height. METHODS: The impact time and loads were measured via inverse dynamic analysis of free landing without knee flexion from three different heights (25, 50 and 75 cm), using five subjects with an average body mass index of 18.8. Three-dimensional data were developed from computed tomography scans and were reprocessed with modeling software before being imported and analyzed by finite element analysis software. The whole leg was considered to be a fixed middle-hinged structure, while impact loads were applied to the femur in an upward direction. RESULTS: Straight landing exerted an enormous amount of pressure on the knee joint as a result of the body's inability to utilize the lower extremity muscles, thereby maximizing the threat of injury when the load exceeds the height-safety threshold. CONCLUSIONS: The researchers conclude that extended-knee landing results in serious deformation of the meniscus and cartilage and increases the risk of bone-to-bone contact and serious knee injury when the load exceeds the threshold safety height. This risk is considerably greater than the risk of injury associated with walking downhill or flexion landing activities. PMID:24141832

Makinejad, Majid Davoodi; Abu Osman, Noor Azuan; Wan Abas, Wan Abu Bakar; Bayat, Mehdi

2013-01-01

112

Development of a dynamic strategy planning theory and system for sustainable river basin land use management.  

PubMed

Land use management is central to government planning for sustainable development. The main purpose of this study is to develop a novel strategy planning theory and system to assist responsible authorities in obtaining alternatives of sustainable top river basin land use management. The concepts and theory of system analysis, driving force-state-response (DSR) framework, and system dynamics are used to establish the DSR dynamic strategy planning procedure in this work. The integrated management of the land, water, and air resources of a river basin system is considered in the procedure. Two modified land use management procedures combined with the DSR dynamic strategy planning procedure are developed in this work. Based on the DSR dynamic strategy planning procedure, the sustainable river basin land use management DSR dynamic decision support system (SRBLUM-DSRD-DSS) is developed by using the Vensim, MS Excel, ArcView, and Visual Basic software. The concepts of object-orientation are used to develop the system dynamic optimization and simulation models of SRBLUM-DSRD-DSS. Based on the modified land use management procedures, SRBLUM-DSRD-DSS is used to assist decision makers in generating the land use plans of the Nankan river basin in Taoyuan County of Taiwan. Since the decisions of land, water and air resources management are still made at different agencies, the land use management system should be modified based on the innovational procedure to implement the management strategy developed in this work. The results show that the modified land use management procedures can be a guidance for the governments in modifying the systems and regulation of urban and regional plans in Taiwan. PMID:15993679

Chen, Ching-Ho; Liu, Wei-Lin; Liaw, Shu-Liang; Yu, Chien-Hwa

2005-06-15

113

Multi-Scale Hydrometeorological Modeling, Land Data Assimilation and Parameter Estimation with the Land Information System  

NASA Technical Reports Server (NTRS)

The Land Information System (LIS; http://lis.gsfc.nasa.gov; Kumar et al., 2006; Peters- Lidard et al.,2007) is a flexible land surface modeling framework that has been developed with the goal of integrating satellite- and ground-based observational data products and advanced land surface modeling techniques to produce optimal fields of land surface states and fluxes. As such, LIS represents a step towards the next generation land component of an integrated Earth system model. In recognition of LIS object-oriented software design, use and impact in the land surface and hydrometeorological modeling community, the LIS software was selected ase co-winner of NASA's 2005 Software of the Year award. LIS facilitates the integration of observations from Earth-observing systems and predictions and forecasts from Earth System and Earth science models into the decision-making processes of partnering agency and national organizations. Due to its flexible software design, LIS can serve both as a Problem Solving Environment (PSE) for hydrologic research to enable accurate global water and energy cycle predictions, and as a Decision Support System (DSS) to generate useful information for application areas including disaster management, water resources management, agricultural management, numerical weather prediction, air quality and military mobility assessment. LIS has evolved from two earlier efforts North American Land Data Assimilation System (NLDAS; Mitchell et al. 2004) and Global Land Data Assimilation System (GLDAS; Rodell al. 2004) that focused primarily on improving numerical weather prediction skills by improving the characterization of the land surface conditions. Both of GLDAS and NLDAS now use specific configurations of the LIS software in their current implementations. In addition, LIS was recently transitioned into operations at the US Air Force Weather Agency (AFWA) to ultimately replace their Agricultural Meteorology (AGRMET) system, and is also used routinely by NOAA's National Centers for Environmental Prediction (NCEP)/Environmental Modeling Center (EMC) for their land data assimilation systems to support weather and climate modeling. LIS not only consolidates the capabilities of these two systems, but also enables a much larger variety of configurations with respect to horizontal spatial resolution, input datasets and choice of land surface model through "plugins,". As described in Kumar et al., 2007, and demonstrated in Case et al., 2008, and Santanello et al., 2009, LIS has been coupled to the Weather Research and Forecasting (WRF) model to support studies of land-atmosphere coupling the enabling ensembles of land surface states to be tested against multiple representations of the atmospheric boundary layer. LIS has also been demonstrated for parameter estimation as described in Peters-Lidard et al. (2008) and Santanello et al. (2007), who showed that the use of sequential remotely sensed soil moisture products can be used to derive soil hydraulic and texture properties given a sufficient dynamic range in the soil moisture retrievals and accurate precipitation inputs. LIS has also recently been demonstrated for multi-model data assimilation (Kumar et al., 2008) using an Ensemble Kalman Filter for sequential assimilation of soil moisture, snow, and temperature. Ongoing work has demonstrated the value of bias correction as part of the filter, and also that of joint calibration and assimilation. Examples and case studies demonstrating the capabilities and impacts of LIS for hydrometeoroogical modeling, assimilation and parameter estimation will be presented as advancements towards the next generation of integrated observation and modeling systems.

Peters-Lidard, Christa D.; Kumar, Sujay V.; Santanello, Joseph A., Jr.; Reichle, Rolf H.

2009-01-01

114

Analysis-test correlation of airbag impact for Mars landing  

SciTech Connect

The NASA Mars Pathfinder mission is intended to demonstrate key low cost technologies for use in future science missions to Mars. Among these technologies is the landing system. Upon entering in Martian atmosphere at about 7000 m/sec., the spacecraft will deploy a series of breaking devices (parachute and solid rockets) to slow down its speed to less than 20 m/sec. as it impacts with the Martian ground. To cushion science instruments form the landing impact, an airbag system is inflated to surround the lander approximately five seconds before impact. After multiple bounces, the lander/airbags comes to rest, the airbags are deflated and retracted, and the lander opens up its petals to allow a microrover to begin exploration. Of interest here, is the final landing phase. Specifically, this paper will focus on the methodology used to simulate the nonlinear dynamics of lander/airbags landing impact, and how this simulation correlates with initial tests.

Salama, M.; Davis, G.; Kuo, C.P. [and others

1994-12-31

115

Analysis of Land Suitable for Algae State of Hawaii  

E-print Network

of Hawaii at Manoa August 2011 #12;i Executive Summary Algae are considered to be a viable crop for biofuel for biofuels has increased interest in growing algae in Hawaii for biofuels. An analysis of algae productionAnalysis of Land Suitable for Algae Production State of Hawaii Prepared by Mele Chillingworth Scott

116

Cost benefit analysis of the location of new forest land  

Microsoft Academic Search

In this paper we show how cost-benefit analysis can be used as a decision support mechanism for the location of new (urban) forest land, starting from the multifunctional role of these new forests. We start with a simple presentation of the cost-benefit analysis (CBA) technique. Key features of this evaluation technique are that (i) all - both positive and negative

Ellen Moons

2002-01-01

117

Urbanization suitability maps: a dynamic spatial decision support system for sustainable land use  

NASA Astrophysics Data System (ADS)

Recent developments in land consumption assessment identify the need to implement integrated evaluation approaches, with particular attention to the development of multidimensional tools for guiding and managing sustainable land use. Land use policy decisions are implemented mostly through spatial planning and its related zoning. This involves trade-offs between many sectorial interests and conflicting challenges seeking win-win solutions. In order to identify a decision-making process for land use allocation, this paper proposes a methodological approach for developing a Dynamic Spatial Decision Support System (DSDSS), denominated Integrated Spatial Assessment (ISA), supported by Geographical Information Systems (GIS) combined with the Analytic Hierarchy Process (AHP). Through empirical investigation in an operative case study, an integrated evaluation approach implemented in a DSDSS helps produce "urbanization suitability maps" in which spatial analysis combined with multi-criteria evaluation methods proved to be useful for both facing the main issues relating to land consumption as well as minimizing environmental impacts of spatial planning.

Cerreta, M.; De Toro, P.

2012-11-01

118

Assessing land-atmosphere coupling using soil moisture from the Global Land Data Assimilation System and observational precipitation  

NASA Astrophysics Data System (ADS)

Precipitation analysis and soil moisture from the Global Land Data Assimilation System (GLDAS) are used to assess the land-atmosphere coupling in boreal summer. Correlations between antecedent soil moisture and precipitation suggest that regions of strong land-atmosphere coupling lie mainly in arid to semiarid transition zones or in semihumid forest to grassland transition zones. They consist of central Eurasia, the region from Mongolia to northern China, southwest China, the Sahel, the northern continental United States, and southern Europe. It is found that over these regions, positive soil moisture feedback accounts for typically 10-20% of the variance of monthly precipitation anomalies with the feedback efficiency of the order of 0.3-0.9 mm month-1 (0.1 standardized soil moisture)-1. While soil moisture feedback is dominated by the positive sign, negative feedback may exist in some areas, such as India and the western part and Quebec province of Canada. Generally, the land-atmosphere coupling strength estimated from the GLDAS data agrees well with those from the observational soil moisture in Illinois and the European Centre for Medium-Range Weather Forecasts 40-year reanalysis (ERA-40) soil moisture product. Physical mechanisms responsible for the findings are further discussed. This study provides a Northern Hemisphere distribution of the land-atmosphere coupling strength, which can be used to test the model simulations on monthly to seasonal time scales.

Zhang, Jingyong; Wang, Wei-Chyung; Wei, Jiangfeng

2008-09-01

119

Spatial Different Analysis of Land Use/Landcover Change And Human Impact In Typical Oasisin Arid Land  

NASA Astrophysics Data System (ADS)

With the current problem of population,resources and environment becoming increasingly intense day by day,the land use/land cover change (LUCC) is one of the core topics on the Present World Change Study.And with the worsening of the global environment,the exhausting of energy and the population explosion,the controversy between the development of oasis economy and the environment has become more and more sharp,which has formed a serious threat to the sustainable development the oasis economy.As a result,the reasonable,coordinate and continuous development is the experimental topic with great theoretical and practical significance in the world.Land use/land cover (LUCC) change has vital significance in environmental variation and the ecology monitoring in the arid and semi-arid areas.This article selects the typical oasis of Awat oasis,which is located in the upstream of Tarim River, where is a typical ecological fragile zone and environmental critical zone.Many effects are caused by the utilization of land and water resources.Along with further development and utilization,great changes of LUCC have been taken place.Based on the research on oasis-desert ecosystem,with the frontier theory of physical geography,LUCC of Awat oasis from 1990 to 2002 are analyzed through the technological train of 3S and statistics,and established the human impact index.Its influencing factors are also identified.First we take the farmland,the wood land,lawn,water,resident,wetland,salt alkali,sand land and naked land as a classification system.Based on the detailed analysis and pretreatment to the remote sensing imagery,we obtained reatively high precision classification result.By the quantification research of human impact to LUCC in Awat,it can be divided into the high human impact area and the low human impact area.The research shows that the changes of pattern are notable and human impact is continuously enhanced,and which is important for the sustainable development of Awat oasis.This research presents the evidence for harmonizing the relations between the land resource and the human activity and provides some methods and experiences for further study of LUCC in aridregion.

Wang, Hongwei; Tiyip, Tash Polat; Ding, Jianli; Luo, Jiangyan

120

A guide to NASA's Pilot Land Data System (PLDS)  

NASA Technical Reports Server (NTRS)

NASA's Pilot Land Data System (PLDS) is a distributed information management system designed to support NASA's land science community. The PLDS provides a wide range of services including management of information about scientific data, access to a library of scientific data, a data ordering capability, communications, connection to data analysis facilities, and electronic mail. The PLDS provides these services by offering the scientist the capability to search for and order data, and to communicate electronically with other scientists and computers. Three functions enable scientists to find what data are available and where they reside. The first two, Find data summaries and Read detailed descriptions give summary and detailed descriptions about data sets or groups of related data sets, science, projects, and institutions which archive land data. The third, gives information about specific pieces of data. This last function has two components, Search systemwide inventory and Search local inventory. The first component enables the user to find data elements (images, geological samples, transects, maps, etc.) that exist anywhere in the PLDS while the second has only information about data at the local site. The first enables the user to find pieces of data from several different data sets with the same temporal and spatial coverage and other elements common to most data sets, while the second allows the user to select a data set based on these descriptors and on those that are unique to a data set. The PLDS provides capabilities that enable electronic file transfers, intercomputer connection, and electronic mail. Both TCP/IP and DECnet protocols are supported via the NASA Science Internet (NIS). Access is also available through Telenet.

1991-01-01

121

23 CFR 971.212 - Federal lands safety management system (SMS).  

...2014-04-01 false Federal lands safety management system (SMS). 971.212 Section 971.212...LANDS HIGHWAYS FOREST SERVICE MANAGEMENT SYSTEMS Forest Highway Program Management Systems § 971.212 Federal lands safety...

2014-04-01

122

78 FR 68811 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land Management Planning Rule AGENCY: Forest Service...National Forest System Land Management Planning Rule will meet in Arlington...National Forest System Land Management Planning Rule. The purpose of...

2013-11-15

123

78 FR 46565 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land Management Planning Rule AGENCY: Forest Service...National Forest System Land Management Planning Rule will meet in West Valley...National Forest System Land Management Planning Rule. The purpose of...

2013-08-01

124

High-performance Earth system modeling with NASA\\/GSFC's Land Information System  

Microsoft Academic Search

The Land Information System software (LIS; http:\\/\\/lis.gsfc.nasa.gov\\/, 2006) has been developed to support high-performance\\u000a land surface modeling and data assimilation. LIS integrates parallel and distributed computing technologies with modern land\\u000a surface modeling capabilities, and establishes a framework for easy interchange of subcomponents, such as land surface physics,\\u000a input\\/output conventions, and data assimilation routines. The software includes multiple land surface models

Christa D. Peters-lidard; P. R. Houser; Y. Tian; S. V. Kumar; J. Geiger; S. Olden; L. Lighty; B. Doty; P. Dirmeyer; J. Adams; K. Mitchell; E. F. Wood; J. Sheffield

2007-01-01

125

Land-use suitability analysis for urban development in Beijing.  

PubMed

Land-use suitability analyses are of considerable use in the planning of mega-cities. An Urban Development Land-use Suitability Mapping (UDLSM) approach has been constructed, based on opportunity and constraint criteria. Two Multi-criteria Evaluation (MCE) methods, the Ideal Point Method (IPM) and Ordered Weighted Averaging (OWA), were used to generate the opportunity map. The protection map was obtained by means of constraint criteria, utilizing the Boolean union operator. A suitability map was then generated by overlaying the opportunity and protection maps. By applying the UDLSM approach to Beijing, its urban development land-use suitability was mapped, and a sensitivity analysis undertaken to examine the robustness of the proposed approach. Indirect validation was achieved by mutual comparisons of suitability maps resulting from the two MCE methods, where the overall agreement of 91% and kappa coefficient of 0.78 indicated that both methods provide very similar spatial land-use suitability distributions. The suitability level decreases from central Beijing to its periphery, and the area classed as suitable amounts to 28% of the total area. Leading attributes of each opportunity factor for suitability were revealed, with 2256 km(2), i.e. 70%, of existing development land being overlaid by suitable areas in Beijing. Conflicting parcels of land were identified by overlaying the resultant map with two previous development blueprints for Beijing. The paper includes several recommendations aimed at improving the long-term urban development plans for Beijing. PMID:25036557

Liu, Renzhi; Zhang, Ke; Zhang, Zhijiao; Borthwick, Alistair G L

2014-12-01

126

Control systems for platform landings cushioned by air bags  

NASA Astrophysics Data System (ADS)

This report presents an exploratory mathematical study of control systems for airdrop platform landings cushioned by airbags. The basic theory of airbags is reviewed and solutions to special cases are noted. A computer program is presented, which calculates the time-dependence of the principal variables during a landing under the action of various control systems. Two existing control systems of open-loop type are compared with a conceptual feedback (closed-loop) system for a fairly typical set of landing conditions. The feedback controller is shown to have performance much superior to the other systems. The feedback system undergoes an interesting oscillation not present in the other systems, the source of which is investigated. Recommendations for future work are included.

Ross, Edward W.

1987-07-01

127

Land-surface atmosphere coupling in an earth system model  

NASA Astrophysics Data System (ADS)

The interaction between the atmosphere and the strongly heterogeneous land surface is one of the central scientific topics within Earth system sciences and especially climate research. Many processes, such as vegetation dynamics and the development of spatial patterns in the Subtropics and permafrost regions, take place on scales much below the scale of model resolution. Thus, it is an important scientific challenge to consider the influence of sub-scale heterogeneity on the vertical near-surface fluxes of energy and water. Most climate models do not take into account the actual scale of surface heterogeneities. When coupling a heterogeneous surface to the atmosphere often coupling methods are employed, which include the underlying assumption that the horizontal extent of the individual heterogeneity is so small that the turbulent vertical fluxes stemming from the different surface heterogeneities within one grid-box have mixed horizontally below the lowest model level of the atmosphere. This assumption allows a comparatively simple land-surface-atmosphere coupling with a horizontally homogeneous state of the atmosphere, but it may also be the source of significant errors. In order to access the extent of error introduced we designed an experiment in which the results of three different coupling schemes were compared. The first one is a parameter-aggregation scheme, the second a flux-aggregation scheme based on the assumption of a horizontally homogeneous atmosphere on the lowest atmospheric model level and the third one is a coupling scheme which allows, up to a given height, for the atmosphere to be horizontally heterogeneous within a grid-box. These coupling methods were implemented in the land-surface model JSBACH which was then coupled to the general circulation model ECHAM6, both part of the Max Planck Institute for Meteorology's earth system model MPI-ESM. In a first step sensitivity studies are being carried out to gain process understanding and to disentangle the direct effects of the land-surface-atmosphere coupling and the atmospheric response. To evaluate the overall impact, of a given coupling scheme, 20-year-AMIP-type simulations were performed. First analysis indicates that the results obtained with the three coupling schemes do significantly differ. These differences are not only visible on a sub-grid scale e.g. the sub-grid fluxes, but also on the grid-scale the choice of the coupling scheme significantly affects the simulated global climate and large-scale patterns. Furthermore the difference in the simulated climate between using the improved and the standard flux-aggregation scheme are in the same order of magnitude as those between the parameter aggregation scheme and the standard flux-aggregation scheme.

de Vrese, Philipp; Hagemann, Stefan

2014-05-01

128

Continental-scale water and energy flux analysis and validation for the North American Land Data Assimilation System project phase 2 (NLDAS-2): 1. Intercomparison and application of model products  

NASA Astrophysics Data System (ADS)

Results are presented from the second phase of the multiinstitution North American Land Data Assimilation System (NLDAS-2) research partnership. In NLDAS, the Noah, Variable Infiltration Capacity, Sacramento Soil Moisture Accounting, and Mosaic land surface models (LSMs) are executed over the conterminous U.S. (CONUS) in realtime and retrospective modes. These runs support the drought analysis, monitoring and forecasting activities of the National Integrated Drought Information System, as well as efforts to monitor large-scale floods. NLDAS-2 builds upon the framework of the first phase of NLDAS (NLDAS-1) by increasing the accuracy and consistency of the surface forcing data, upgrading the land surface model code and parameters, and extending the study from a 3-year (1997-1999) to a 30-year (1979-2008) time window. As the first of two parts, this paper details the configuration of NLDAS-2, describes the upgrades to the forcing, parameters, and code of the four LSMs, and explores overall model-to-model comparisons of land surface water and energy flux and state variables over the CONUS. Focusing on model output rather than on observations, this study seeks to highlight the similarities and differences between models, and to assess changes in output from that seen in NLDAS-1. The second part of the two-part article focuses on the validation of model-simulated streamflow and evaporation against observations. The results depict a higher level of agreement among the four models over much of the CONUS than was found in the first phase of NLDAS. This is due, in part, to recent improvements in the parameters, code, and forcing of the NLDAS-2 LSMs that were initiated following NLDAS-1. However, large inter-model differences still exist in the northeast, Lake Superior, and western mountainous regions of the CONUS, which are associated with cold season processes. In addition, variations in the representation of sub-surface hydrology in the four LSMs lead to large differences in modeled evaporation and subsurface runoff. These issues are important targets for future research by the land surface modeling community. Finally, improvement from NLDAS-1 to NLDAS-2 is summarized by comparing the streamflow measured from U.S. Geological Survey stream gauges with that simulated by four NLDAS models over 961 small basins.

Xia, Youlong; Mitchell, Kenneth; Ek, Michael; Sheffield, Justin; Cosgrove, Brian; Wood, Eric; Luo, Lifeng; Alonge, Charles; Wei, Helin; Meng, Jesse; Livneh, Ben; Lettenmaier, Dennis; Koren, Victor; Duan, Qingyun; Mo, Kingtse; Fan, Yun; Mocko, David

2012-02-01

129

Land-use/land-cover change detection using change-vector analysis in posterior probability space  

NASA Astrophysics Data System (ADS)

Land use/land cover change is an important field in global environmental change research. Remote sensing is a valuable data source from which land use/land cover change information can be extracted efficiently. A number of techniques for accomplishing change detection using satellite imagery have been formulated, applied, and evaluated, which can be generally grouped into two types. (1) Those based on spectral classification of the input data such as post-classification comparison and direct two-date classification; and (2) those based on radiometric change between different acquisition dates. The shortage of type 1 is cumulative error in image classification of an individual date. However, radiometric change approaches has a strict requirement for reliable image radiometry. In light of the above mentioned drawbacks of those two types of change detection methods, this paper presents a new method named change vector analysis in posterior probability space (CVAPS). Change-vector analysis (CVA) is one of the most successful radiometric change-based approaches. CVAPS approach incorporates post-classification comparison method and CVA approach, which is expected to inherit the advantages of two traditional methods and avoid their defects at the same time. CVAPS includes the following four steps. (1) Images in different periods are classified by certain classifier which can provide posterior probability output. Then, the posterior probability can be treated as a vector, the dimension of which is equal to the number of classes. (2) A procedure similar with CVA is employed. Compared with traditional CVA, new method analyzes the change vector in posterior probability space instead of spectral feature space. (3) A semiautomatic method, named Double-Window Flexible Pace Search (DFPS), is employed to determine the threshold of change magnitude. (4) Change category is discriminated by cosines of the change vectors. CVAPS approach was applied and validated by a case study of land use change detection in urban area of Shenzhen, China using multi-temporal TM data. Kappa coefficients of "change/no-change" detection and "from-to" types of change detection were employed for accuracy assessment. The experimental results show that CVAPS outperform than post-classification comparison method and can avoid cumulative error effectively. Besides, radiometric correction is not needed in this method compared with traditional CVA. Therefore, it is indicated that CVAPS is potentially useful in land-use/land-cover change detection.

Chen, Xuehong; Chen, Jin; Shen, Miaogen; Yang, Wei

2008-10-01

130

78 FR 23219 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land Management Planning Rule AGENCY: Forest Service...National Forest System Land Management Planning Rule will meet in Fort Collins...Secretary on the Proposed Land Management Planning Directives. DATES: The...

2013-04-18

131

78 FR 34034 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land Management Planning Rule AGENCY: Forest Service...National Forest System Land Management Planning Rule will meet in Salt Lake...Secretary on the Proposed Land Management Planning Directives. The meeting...

2013-06-06

132

Task Analysis of Shuttle Entry and Landing Activities  

NASA Technical Reports Server (NTRS)

The Task Analysis of Shuttle Entry and Landing (E/L) Activities documents all tasks required to land the Orbiter following an STS mission. In addition to analysis of tasks performed, task conditions are described, including estimated time for completion, altitude, relative velocity, normal and lateral acceleration, location of controls operated or monitored, and level of g's experienced. This analysis precedes further investigations into potential effects of zero g on piloting capabilities for landing the Orbiter following long-duration missions. This includes, but is not limited to, researching the effects of extended duration missions on piloting capabilities. Four primary constraints of the analysis must be clarified: (1) the analysis depicts E/L in a static manner--the actual process is dynamic; (2) the task analysis was limited to a paper analysis, since it was not feasible to conduct research in the actual setting (i.e., observing or filming duration an actual E/L); (3) the tasks included are those required for E/L during nominal, daylight conditions; and (4) certain E/L tasks will vary according to the flying style of each commander.

Holland, Albert W.; Vanderark, Stephen T.

1993-01-01

133

Preliminary Design and Analysis for China Mars Landing Exploration Mission  

NASA Astrophysics Data System (ADS)

China's first Mars probe, "Yinghuo-1", is expected to be launched using Russia's carrier rocket in the year 2011. After that, china will carry out an independent Mars landing exploration activities. This paper address the preliminary design and analysis for China Mars landing exploration mission. First of all, the aim of mission and science object are proposed; then, the various proper scientific instruments are suggested; next, the optimal Eath-Mars transfer trajectories are analyzed according to C3 contours. Finally, the innovative EDL navigation and guidance scheme is also developed.

Li, Shuang; Peng, Yuming

134

Automated Loads Analysis System (ATLAS)  

NASA Technical Reports Server (NTRS)

ATLAS is a generalized solution that can be used for launch vehicles. ATLAS is used to produce modal transient analysis and quasi-static analysis results (i.e., accelerations, displacements, and forces) for the payload math models on a specific Shuttle Transport System (STS) flight using the shuttle math model and associated forcing functions. This innovation solves the problem of coupling of payload math models into a shuttle math model. It performs a transient loads analysis simulating liftoff, landing, and all flight events between liftoff and landing. ATLAS utilizes efficient and numerically stable algorithms available in MSC/NASTRAN.

Gardner, Stephen; Frere, Scot; O’Reilly, Patrick

2013-01-01

135

Land degradation analysis based on the land use changes and land degradation evaluation in the Huan Beijing area  

NASA Astrophysics Data System (ADS)

Using remote sensing data of TM and ETM+ in 1992 and 2002, land degradation based on land use changes, especially sand changes were analyzed and land degradation status in 2002 was evaluated in the Huan Beijing Area. The area of sand in 2002 is 6669.6 km2, increased 716.2 km2 compared to that in 1991, and most of the newly-produced sand came from grassland. Land degradation status in 2002 was evaluated by the combination of vegetation, soil and topography information and the region was divided by 1km ×1km cell as the evaluation unit by the application of the GIS. The indicators of land degradation evaluation included soil organic, soil depth, vegetation cover (NDVI) and slope. Land degradation index (DI) was computed, considering the contribution of different indicators to land degradation. The land degradation status was divided into four types according to DI, no-degradation (DI > = 55), slight degradation (50 = < DI < 55), moderate degradation (40 = < DI < 50) and severe degradation (DI < 40). The results showed that the area of degraded land is 132900 km2, which occupied the percent 58.2 of the whole Huan Beijing Area and the proportion of slightly-degraded land to degraded land is about 0.47. The political county taken as an evaluation unit, the partition of land degradation in this area was also analyzed based on land degradation area proportion and degree. Six types of land degradation partition were got.

Guo, Xudong; Wang, Jing; Xie, Junqi; He, Ting; Lian, Gang; Lv, Chunyan

2005-10-01

136

US army land condition-trend analysis (LCTA) program  

Microsoft Academic Search

The US Army Land Condition-Trend Analysis (LCTA) program is a standardized method of data collection, analysis, and reporting\\u000a designed to meet multiple goals and objectives. The method utilizes vascular plant inventories, permanent field plot data,\\u000a and wildlife inventories. Vascular plant inventories are used for environmental documentation, training of personnel, species\\u000a identification during LCTA implementation, and as a survey for state

Victor E. Diersing; Robert B. Shaw; David J. Tazik

1992-01-01

137

Improved inflatable landing systems for low cost planetary landers  

NASA Astrophysics Data System (ADS)

Inflatable landing systems have been traditionally perceived as a cost-effective solution to the problem of landing a spacecraft on a planetary surface. To date, the systems used have all employed the approach of surrounding the lander with non-vented airbags where the lander on impact bounces a number of times until the impact energy is dissipated. However, the reliability record of such systems is not at all good. This paper examines the problems involved in the use of non-vented airbags, and how these problems have been overcome by the use of vented airbags in terrestrial systems. Using a specific case study, it is shown that even the basic passive type of venting can give significant mass reductions. It is also shown that actively controlling the venting based on the landing scenario can further enhance the performance of vented airbags.

Northey, Dave; Morgan, Chris

2006-10-01

138

Improved inflatable landing systems for low cost planetary landers  

NASA Astrophysics Data System (ADS)

Inflatable landing systems have been traditionally perceived as a cost-effective solution to the problem of landing a spacecraft on a planetary surface. To date the systems used have all employed the approach of surrounding the lander with non-vented airbags where the lander bounces on impact a number of times until the impact energy is dissipated. However the reliability record of such systems is not at all good. This paper examines the problems involved in the use of non-vented airbags, and how these problems have been overcome by the use of vented airbags in terrestrial systems. Using a specific case study, it is shown that even the basic passive type of venting can give significant mass reductions. It is also shown that actively controlling the venting based on the landing scenario can further enhance the performance of vented airbags.

Northey, Dave; Morgan, Chris

2003-11-01

139

Validation of an Active Gear, Flexible Aircraft Take-off and Landing analysis (AGFATL)  

NASA Technical Reports Server (NTRS)

The results of an analytical investigation using a computer program for active gear, flexible aircraft take off and landing analysis (AGFATL) are compared with experimental data from shaker tests, drop tests, and simulated landing tests to validate the AGFATL computer program. Comparison of experimental and analytical responses for both passive and active gears indicates good agreement for shaker tests and drop tests. For the simulated landing tests, the passive and active gears were influenced by large strut binding friction forces. The inclusion of these undefined forces in the analytical simulations was difficult, and consequently only fair to good agreement was obtained. An assessment of the results from the investigation indicates that the AGFATL computer program is a valid tool for the study and initial design of series hydraulic active control landing gear systems.

Mcgehee, J. R.

1984-01-01

140

Mars Science Laboratory Entry, Descent, and Landing System Overview  

NASA Technical Reports Server (NTRS)

In 2010, the Mars Science Laboratory (MSL) mission will pioneer the next generation of robotic Entry, Descent, and Landing (EDL) systems by delivering the largest and most capable rover to date to the surface of Mars. In addition to landing more mass than prior missions to Mars, MSL will offer access to regions of Mars that have been previously unreachable. The MSL EDL sequence is a result of a more stringent requirement set than any of its predecessors. Notable among these requirements is landing a 900 kg rover in a landing ellipse much smaller than that of any previous Mars lander. In meeting these requirements, MSL is extending the limits of the EDL technologies qualified by the Mars Viking, Mars Pathfinder, and Mars Exploration Rover missions.

Prakash, Ravi; Burkhart, P. Dan; Chen, Allen; Comeaux, Keith A.; Guernsey, Carl S.; Devin, M. Kipp; Mendeck, Gavin F.; Powell, Richard W.; Rivellini, Tommaso P.; San Martin, A. Miguel; Sell, Steven W.; Steltzner, Adam D.; Way, David W.

2008-01-01

141

An analysis of metropolitan land-use by machine processing of earth resources technology satellite data  

NASA Technical Reports Server (NTRS)

A successful application of state-of-the-art remote sensing technology in classifying an urban area into its broad land use classes is reported. This research proves that numerous urban features are amenable to classification using ERTS multispectral data automatically processed by computer. Furthermore, such automatic data processing (ADP) techniques permit areal analysis on an unprecedented scale with a minimum expenditure of time. Also, classification results obtained using ADP procedures are consistent, comparable, and replicable. The results of classification are compared with the proposed U. S. G. S. land use classification system in order to determine the level of classification that is feasible to obtain through ERTS analysis of metropolitan areas.

Mausel, P. W.; Todd, W. J.; Baumgardner, M. F.

1976-01-01

142

Research priorities in land use and land-cover change for the Earth system and integrated assessment modelling  

SciTech Connect

This special issue has highlighted recent and innovative methods and results that integrate observations and AQ3 modelling analyses of regional to global aspect of biophysical and biogeochemical interactions of land-cover change with the climate system. Both the Earth System and the Integrated Assessment modeling communities recognize the importance of an accurate representation of land use and land-cover change to understand and quantify the interactions and feedbacks with the climate and socio-economic systems, respectively. To date, cooperation between these communities has been limited. Based on common interests, this work discusses research priorities in representing land use and land-cover change for improved collaboration across modelling, observing and measurement communities. Major research topics in land use and land-cover change are those that help us better understand (1) the interaction of land use and land cover with the climate system (e.g. carbon cycle feedbacks), (2) the provision of goods and ecosystem services by terrestrial (natural and anthropogenic) land-cover types (e.g. food production), (3) land use and management decisions and (4) opportunities and limitations for managing climate change (for both mitigation and adaptation strategies).

Hibbard, Kathleen A.; Janetos, Anthony C.; Van Vuuren, Detlef; Pongratz, Julia; Rose, Steven K.; Betts, Richard; Herold, Martin; Feddema, Johannes J.

2010-11-15

143

An analysis of landing rates and separations at the Dallas/Fort Worth International Airport  

NASA Technical Reports Server (NTRS)

Advanced air traffic management systems such as the Center/TRACON Automation System (CTAS) should yield a wide range of benefits, including reduced aircraft delays and controller workload. To determine the traffic-flow benefits achievable from future terminal airspace automation, live radar information was used to perform an analysis of current aircraft landing rates and separations at the Dallas/Fort Worth International Airport. Separation statistics that result when controllers balance complex control procedural constraints in order to maintain high landing rates are presented. In addition, the analysis estimates the potential for airport capacity improvements by determining the unused landing opportunities that occur during rush traffic periods. Results suggest a large potential for improving the accuracy and consistency of spacing between arrivals on final approach, and they support earlier simulation findings that improved air traffic management would increase capacity and reduce delays.

Ballin, Mark G.; Erzberger, Heinz

1996-01-01

144

The KamLAND full-volume calibration system  

Microsoft Academic Search

We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result,

B. E. Berger; J. Busenitz; T. Classen; M. P. Decowski; D. A. Dwyer; G. Elor; A. Frank; S. J. Freedman; B. K. Fujikawa; M. Galloway; F. Gray; K. M. Heeger; L. Hsu; K. Ichimura; R. Kadel; G. Keefer; C. Lendvai; D. McKee; T. O'Donnell; A. Piepke; H. M. Steiner; D. Syversrud; J. Wallig; L. A. Winslow; T. Ebihara; S. Enomoto; K. Furuno; Y. Gando; H. Ikeda; K. Inoue; Y. Kishimoto; M. Koga; Y. Minekawa; T. Mitsui; K. Nakajima; K. Nakamura; K. Owada; I. Shimizu; Y. Shimizu; J. Shirai; F. Suekane; A. Suzuki; K. Tamae; S. Yoshida; A. Kozlov; H. Murayama; C. Grant; D. S. Leonard; K.-B. Luk; C. Jillings; C. Mauger; R. D. McKeown; C. Zhang; J. Maricic; T. Miletic; M. Batygov; J. G. Learned; S. Matsuno; S. Pakvasa; J. Foster; G. A. Horton-Smith; A. Tang; S. Dazeley; K. E. Downum; G. Gratta; K. Tolich; W. Bugg; Y. Efremenko; Y. Kamyshkov; O. Perevozchikov; H. J. Karwowski; D. M. Markoff; W. Tornow; F. Piquemal; J.-S. Ricol

2009-01-01

145

Subsurface drip systems for land application of residential wastewater  

E-print Network

'Hanis, Texas and the other in Stephenville, Texas. The land application systems are comprised of a filtration system and two subsurface drip application areas. One application area contains 4.0 L/h (1.08 gal/h) emitter rate drip tubing and the other area...

Neal, Byron Anthony

2012-06-07

146

RITD - Adapting Mars Entry, Descent and Landing System for Earth  

NASA Astrophysics Data System (ADS)

A new generation of inflatable Entry, Descent and Landing System (EDLS) for Mars has been developed. It is used in both the initial atmospheric entry and atmospheric descent before the semi-hard impact of the penetrator into Martian surface. The EDLS applicability to Earth's atmosphere is studied by the EU/RITD [1] project. Project focuses to the analysis and tests of the transonic behaviour of this compact and light weight payload entry system at the Earth re-entry. 1. EDLS for Earth The dynamical stability of the craft is analysed, concentrating on the most critical part of the atmospheric re-entry, the transonic phase. In Martian atmosphere the MetNet vehicle stability during the transonic phase is understood. However, in the more dense Earth's atmosphere, the transonic phase is shorter and turbulence more violent. Therefore, the EDLS has to be sufficiently dynamically stable to overcome the forces tending to deflect the craft from its nominal trajectory and attitude. The preliminary design of the inflatable EDLS for Earth will be commenced once the scaling of the re-entry system and the dynamical stability analysis have been performed. The RITD-project concentrates on mission and applications achievable with the current MetNet-type (i.e. 'Mini-1' category) of lander, and on requirements posed by other type Earth re-entry concepts. 2. Entry Angle Determination for Mini-1 - lander For successful Earth landing, the suitable re-entry angle and velocity with specific descent vehicle (DV) mass and heat flux parameters need to be determined. These key parameters in determining the Earth re-entry for DV are: qmax (kW/m2): maximal specific heat flux, Q (MJ/m2): specific integral heat flux to DV front shield, m (kg): descent vehicle (DV) mass, V (m/s): re-entry velocity and ? (deg.): flight-path angle at Earth re-entry For Earth re-entry, the calculation results in the optimal value of entry velocity for MetNet ('Mini-1' category) -type lander, with mass of 22kg, being VSOL = 5268 m/s. Using the basic pre-defined parameters for MetNet-type of lander in Earth atmosphere, we get the optimal angle of ? = -3.06 degrees for Earth re-entry. 3. Payload Mass for Earth Entry DV One of the key elements in Earth entry lander is the amount of available payload mass. The payload mass depends on, e.g., the lander size, landing type (soil or water), heat shield durability and additional landing gear. The payload mass will have an impact to the center of gravity of the lander. The payload with a 'low' CoG (compared the the lander structure) has a larger tolerance than the payload with 'high' CoG. In cases where payload CoG causes instability, the extra balance mass can be used to adjust CoG. This balance mass will reduce the available payload mass. A major limitation for payload mass is the heat shielding. Acknowledgements The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 263255. References [1] http://ritd.fmi.fi

Heilimo, Jyri; Harri, Ari-Matti; Aleksashkin, Sergey; Koryanov, Vsevolod; Arruego, Ignacio; Schmidt, Walter; Haukka, Harri; Finchenko, Valery; Martynov, Maxim; Ostresko, Boris; Ponomarenko, Andrey; Kazakovtsev, Viktor; Martin, Susanna; Siili, Tero

2014-05-01

147

RITD - Adapting Mars Entry, Descent and Landing System for Earth  

NASA Astrophysics Data System (ADS)

Abstract A new generation of in?atable Entry, Descent and Landing System (EDLS) or Mars has been developed. It is used in both the initial atmospheric entry and atmospheric descent before the semi-hard impact of the penetrator into Martian surface. The EDLS applicability to Earth’s atmosphere is studied by the EU/RITD [1] project. Project focuses to the analysis and tests of the transonic behaviour of this compact and light weight payload entry system at the Earth re-entry 1. EDLS for Earth The dynamical stability of the craft is analysed, concentrating on the most critical part of the atmospheric re-entry, the transonic phase. In Martian atmosphere the MetNet vehicle stability during the transonic phase is understood. However, in the more dense Earth’s atmosphere, the transonic phase is shorter and turbulence more violent. Therefore, the EDLS has to be sufficiently dynamically stable to overcome the forces tending to deflect the craft from its nominal trajectory and attitude. The preliminary design of the inflatable EDLS for Earth will be commenced once the scaling of the re-entry system and the dynamical stability analysis have been performed. The RITD-project concentrates on mission and applications achievable with the current MetNet-type (i.e. “Mini-1” category) of lander, and on requirements posed by other type Earth re-entry concepts. 2. Entry Angle Determination for Mini-1 - lander For successful Earth landing, the suitable re-entry angle and velocity with specific descent vehicle (DV) mass and heat flux parameters need to be determined. These key parameters in determining the Earth re-entry for DV are: - qmax (kW/m2): maximal specific heat flux, - Q (MJ/m2): specific integral heat flux to DV front shield, - m (kg): descent vehicle (DV) mass, - V (m/s): re-entry velocity and - theta(deg.): flight-path angle at Earth re-entry For Earth re-entry, the calculation results in the optimal value of entry velocity for MetNet (“Mini-1” category) -type lander, with mass of 22kg, being VSOL = 5268 m/s. Using the basic pre-defined parameters for MetNet-type of lander in Earth atmosphere, we get the optimal angle of = -3.06 degrees for Earth re-entry. 3. Payload Mass for Earth Entry DV One of the key elements in Earth entry lander is the amount of available payload mass. The payload mass depends on, e.g., the lander size, landing type (soil or water), heat shield durability and additional landing gear. The payload mass will have an impact to the center of gravity of the lander. The payload with a “low” CoG (compared the the lander structure) has a larger tolerance than the payload with “high” CoG. In cases where payload CoG causes instability, the extra balance mass can be used to adjust CoG. This balance mass will reduce the available payload mass. A major limitation for payload mass is the heat shielding. Acknowledgements The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 263255. References [1] http://ritd.fmi.fi

Heilimo, Jyri; Aleksashkin, Sergey; Martynov, Maxim; Schmidt, Walter; Harri, Ari-Matti; Vsevolod Koryanov, D.; Kazakovtcev, Victor; Haukka, Harri; Arruego, Ignacio; Finchenko, Valery; Ostresko, Boris; Ponomarenko, Andrei; Martin, Susanna; Siili, Tero

148

Visualization and Analysis of Multi-scale Land Surface Products via Giovanni Portals  

NASA Technical Reports Server (NTRS)

Large volumes of MODIS land data products at multiple spatial resolutions have been integrated into the Giovanni online analysis system to support studies on land cover and land use changes,focused on the Northern Eurasia and Monsoon Asia regions through the LCLUC program. Giovanni (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) is a Web-based application developed by the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC), providing a simple and intuitive way to visualize, analyze, and access Earth science remotely-sensed and modeled data.Customized Giovanni Web portals (Giovanni-NEESPI andGiovanni-MAIRS) have been created to integrate land, atmospheric,cryospheric, and societal products, enabling researchers to do quick exploration and basic analyses of land surface changes, and their relationships to climate, at global and regional scales. This presentation shows a sample Giovanni portal page, lists selected data products in the system, and illustrates potential analyses with imagesand time-series at global and regional scales, focusing on climatology and anomaly analysis. More information is available at the GES DISCMAIRS data support project portal: http:disc.sci.gsfc.nasa.govmairs.

Shen, Suhung; Kempler, Steven J.; Gerasimov, Irina V.

2013-01-01

149

Using Geo-informational System for determining land degradation processes  

NASA Astrophysics Data System (ADS)

The largest part of agricultural lands of the Republic of Moldova is concentrated in the arid zone Frequent droughts once in 2-4 years inflict vital causalities to agriculture of the Republic of Moldova However droughts influence doesn t only limit itself to forming production Drought after-effect is highly ruinous for water reserves industrial enterprises functioning rhythm and human health Droughts make for the drying up and crumbling of soil which is subject to excessive human influence and result in land degradation desertification Term desertification means land degradation in the droughty zones It is necessary to mention that the droughty ecosystems are extremely fragile and sensitive overexploitation Nowadays in the Republic of Moldova 33-37 of agricultural lands is eroded Republic of Moldova joined the United Nations Convention to Combat Desertification on December 24 1998 The Government of the Republic of Moldova ratified the National Action Plan to Combat Desertification in 2000 Within the framework of executing the National Action Plan by National Committee to Combat Desertification Geo-informational System on arid questions was organized In addition a lot of indexes corresponding to international standards were used for the evaluation of drought of the territory and land degradation processes Mostly this information is presented in maps erosion landslides aridity water resources A rich experience of using satellite information for determining land degradation demonstrates high effectiveness of this method Satellite

Mangul, I.; Mangul, S.

150

Systemic change increases forecast uncertainty of land use change models  

NASA Astrophysics Data System (ADS)

Cellular Automaton (CA) models of land use change are based on the assumption that the relationship between land use change and its explanatory processes is stationary. This means that model structure and parameterization are usually kept constant over time, ignoring potential systemic changes in this relationship resulting from societal changes, thereby overlooking a source of uncertainty. Evaluation of the stationarity of the relationship between land use and a set of spatial attributes has been done by others (e.g., Bakker and Veldkamp, 2012). These studies, however, use logistic regression, separate from the land use change model. Therefore, they do not gain information on how to implement the spatial attributes into the model. In addition, they often compare observations for only two points in time and do not check whether the change is statistically significant. To overcome these restrictions, we assimilate a time series of observations of real land use into a land use change CA (Verstegen et al., 2012), using a Bayesian data assimilation technique, the particle filter. The particle filter was used to update the prior knowledge about the parameterization and model structure, i.e. the selection and relative importance of the drivers of location of land use change. In a case study of sugar cane expansion in Brazil, optimal model structure and parameterization were determined for each point in time for which observations were available (all years from 2004 to 2012). A systemic change, i.e. a statistically significant deviation in model structure, was detected for the period 2006 to 2008. In this period the influence on the location of sugar cane expansion of the driver sugar cane in the neighborhood doubled, while the influence of slope and potential yield decreased by 75% and 25% respectively. Allowing these systemic changes to occur in our CA in the future (up to 2022) resulted in an increase in model forecast uncertainty by a factor two compared to the assumption of a stationary system. This means that the assumption of a constant model structure is not adequate and largely underestimates uncertainty in the forecast. Non-stationarity in land use change projections is challenging to model, because it is difficult to determine when the system will change and how. We believe that, in sight of these findings, land use change modelers should be more aware, and communicate more clearly, that what they try to project is at the limits, and perhaps beyond the limits, of what is still projectable. References Bakker, M., Veldkamp, A., 2012. Changing relationships between land use and environmental characteristics and their consequences for spatially explicit land-use change prediction. Journal of Land Use Science 7, 407-424. Verstegen, J.A., Karssenberg, D., van der Hilst, F., Faaij, A.P.C., 2012. Spatio-Temporal Uncertainty in Spatial Decision Support Systems: a Case Study of Changing Land Availability for Bioenergy Crops in Mozambique. Computers , Environment and Urban Systems 36, 30-42.

Verstegen, J. A.; Karssenberg, D.; van der Hilst, F.; Faaij, A.

2013-12-01

151

TOXIC ORGANIC VOLATILIZATION FROM LAND TREATMENT SYSTEMS  

EPA Science Inventory

Methodology was evaluated for estimating volatilization of toxic organic chemicals from unsaturated soils. Projections were compared with laboratory data for simulated rapid infiltration wastewater treatment systems receiving primary municipal wastewater spiked with a suite of 18...

152

Pattern analysis and intensity evaluation of urban land use in east peral river dleta, China  

Microsoft Academic Search

Using four classified Landsat images and two vector land use map that covered the study area, the change of urban land use, urban land patterns, and urban land intensity were quantized. After urban expansion analysis, changes of landscape pattern were then quantified by a series of landscape metrics. Additionally, two indices, IULU and LOE, were proposed by us to evaluate

Zhi-qiang Lv

2010-01-01

153

Research on Decision-Making Support of Chineserural Land Tenure Information System  

NASA Astrophysics Data System (ADS)

Since 1949, the information of land tenure has a positive effect on defining the scope of collective land and state-owned land, implementing the system of cultivated land protection and land use control, designing general land use planning, etc. But as the economic and social development, the existing land tenure information is not appropriate anymore and results in many problems. The emphasis in the near future should be placed on establishing rural land tenure information system including cadastral management system, the uniform property registration system and cadastral management information system, defining the scope and content of various collective land ownership, securing peasants' land tenure rights, shortening the gap between urban and rural areas, all of which will guarantee the effective use of information of land tenure for the government's decision-making.

Tan, Jun; Su, Hongyou

154

North American Land Change Monitoring System: Current Status and Future Development  

NASA Astrophysics Data System (ADS)

At the Land Cover Summit meeting held in Washington, DC in September 2006 the North American Land Change Monitoring System (NLCMS) project was initiated between representatives from the US Geological Survey (USGS), the National Institute of Geographic Statistics and Information of Mexico (INEGI) and the Canada Centre for Remote Sensing (CCRS). The objective of the NALCMS is a joint effort to create a harmonized system for multi-scale and multi-temporal monitoring and reporting of North American land cover change. The proposed system couples 250m and 30m resolutions, offering products relevant at both spatial scales. The two spatial resolutions will provide users with investigation, confirmation, calibration, and assessment of 250m change products with 30m product support. This combination of spatial resolutions offers a valuable increase in temporal frequency, context, and strategic prioritization for 30m products. In due course these land change products can provide continental, national, and regional consistency to land cover and land cover change analysis.

Pouliot, D.; Homer, C.; Ressl, R.; Takaki, F.; Meneses, C.; Latifovic, R.; Giri, C.; Colditz, R.; Jimenez, F.; Orozco, R.; Hossain, N.; Lopez, G.; Palafox, R.; Díaz, P.

2009-05-01

155

Evolution of public land mobile telephone systems in Europe  

NASA Astrophysics Data System (ADS)

Public land mobile systems in service or planned in Europe, and the requirements and characteristics envisaged for the European Mobile Communication System are described. These include use of the 900 MHz band mobile stations in all participating countries, public services and data networks, no significant modification of the fixed telephone networks, and an internationally standardized signalling system for the interconnection of the mobile switching centers.

Failli, R.

1983-06-01

156

Satellite Power System (SPS) resource requirements (critical materials, energy and land)  

NASA Technical Reports Server (NTRS)

The resource impacts of the proposed satellite power system are evaluated. Three classes of resource impacts are considered separately: critical materials, energy, and land use. The analysis focuses on the requirements associated with the annual development of two five-gigawatt satellites and the associated receiving facilities.

Kotin, A. D.

1978-01-01

157

NATIONAL FOREST SYSTEM LAND MANAGEMENT PLANNING RULE NATIONAL SCIENCE PANEL  

E-print Network

1 NATIONAL FOREST SYSTEM LAND MANAGEMENT PLANNING RULE NATIONAL SCIENCE PANEL Washington, D, 2010 to provide comments on particular topics regarding the development of the new planning rule. I of the planning rule. In addition to writing a new rule, lawmakers and the USFS should convene a National Forest

Nie, Martin

158

STATIC INITIAL AZIMUTH UPDATE METHOD IN LAND NAVIGATION SYSTEMS  

Microsoft Academic Search

The paper presents a method for the initial azimuth selection in Land Navigation Systems (LNS), applying the ZUPT (Zero-velocity UPdaTe) technique. This technique is understood as a correction of the initial setting achieve the best accuracy of the navigation. The case of the inaccurate initial azimuth during stopping of the vehicle (after short drive) in order to setting is considered.

Jacek Szymanowski

159

A DEMONSTRATION PROJECT OF NGH LAND TRANSPORTATION SYSTEM  

Microsoft Academic Search

Joint project by Chugoku Electric Power Co., Inc. (CEP) and Mitsui Engineering & Shipbuilding Co. Ltd. (MES) has focused on a demonstration of land transportation system of Natural Gas Hydrate (NGH). The project started in summer of 2006 supported by New Energy and Industrial Technology Development Organization (NEDO). The construction of production plant is scheduled to be completed in spring

Shigeru Watanabe; Shinji Takahashi; Hiroshi Mizubayashi; Shinji Murata; Hideyuki Murakami

160

TOXIC AND PRIORITY ORGANICS IN MUNICIPAL SLUDGE LAND TREATMENT SYSTEMS  

EPA Science Inventory

The goal of the research reported herein was to begin a methodical investigation of organic priority pollutants applied to plant-soil systems at rates characteristic of municipal sludge land treatment. A single chemical was applied at rates of 0.1, 10, and 100-fold of the expecte...

161

FIELD AND LABORATORY EVALUATION OF PETROLEUM LAND TREATMENT SYSTEM CLOSURE  

EPA Science Inventory

The objectives of the research were to measure and interpret the surface soil changes in relation to the quality of runoff water from petroleum refinery land treatment (LT) systems undergoing simulated closure. Waste/soils from four LT sites were studied for chemical transformati...

162

Land reclamation information system of mining area based on GIS  

NASA Astrophysics Data System (ADS)

Land reclamation of mining area is an interdisciplinary. The data to be dealt with involves the fields of mining, geology, geography, soil, agriculture and forest, biology, society, economy, etc, with the characteristic of plenty of data and complicated relationship. The traditional data processing cannot meet the demand of land reclamation. The research is based on the result of prevenient scholars to further study the application of GIS. In the paper, the connotation and functions of Land reclamation system is mainly explained, and data organizing pattern is systematically analyzed based on MapX and Oracle Spatial, then a new method based on GIS and CA is putting forward to simulate the distribution of digging area and filling area on the condition of the earthwork balance, finally a reclamation land use mode of rational proportion and layout is set up based on analyzing methods of GIS and the optimizing method of GA. The research can provide a useful tool for land reclamation management and decision-making.

Chen, Quiji; Hu, Zhenqi; Liu, Chuanghua; Gu, Jianghua; Wang, Yongping

2007-06-01

163

Mars Science Laboratory Entry, Descent, and Landing System Overview  

NASA Technical Reports Server (NTRS)

In 2012, the Mars Science Laboratory (MSL) mission will pioneer the next generation of robotic Entry, Descent, and Landing (EDL) systems by delivering the largest and most capable rover to date to the surface of Mars. In addition to landing more mass than prior missions to Mars, MSL will offer access to regions of Mars that have been previously unreachable. The MSL EDL sequence is a result of a more stringent requirement set than any of its predecessors. Notable among these requirements is landing a 900 kg rover in a landing ellipse much smaller than that of any previous Mars lander. In meeting these requirements, MSL is extending the limits of the EDL technologies qualified by the Mars Viking, Mars Pathfinder, and Mars Exploration Rover missions. Thus, there are many design challenges that must be solved for the mission to be successful. Several pieces of the EDL design are technological firsts, such as guided entry and precision landing on another planet, as well as the entire Sky Crane maneuver. This paper discusses the MSL EDL architecture and discusses some of the challenges faced in delivering an unprecedented rover payload to the surface of Mars.

Steltzner, Adam D.; Burkhart, P. Dan; Chen, Allen; Comeaux, Keith A.; Guernsey, Carl S.; Kipp, Devin M.; Lorenzoni, Leila V.; Mendeck, Gavin F.; Powell, Richard W.; Rivellini, Tommaso P.; San Martin, A. Miguel; Sell, Steven W.; Prakash, Ravi; Way, David W.

2010-01-01

164

A robust signalling system for land mobile satellite services  

NASA Technical Reports Server (NTRS)

Presented here is a signalling system optimized to ensure expedient call set-up for satellite telephony services in a land mobile environment. In a land mobile environment, the satellite to mobile link is subject to impairments from multipath and shadowing phenomena, which result in signal amplitude and phase variations. Multipath, caused by signal scattering and reflections, results in sufficient link margin to compensate for these variations. Direct signal attenuation caused by shadowing due to buildings and vegetation may result in attenuation values in excess of 10 dB and commonly up to 20 dB. It is not practical to provide a link with sufficient margin to enable communication when the signal is blocked. When a moving vehicle passes these obstacles, the link will experience rapid changes in signal strength due to shadowing. Using statistical models of attenuation as a function of distance travelled, a communication strategy has been defined for the land mobile environment.

Irish, Dale; Shmith, Gary; Hart, Nick; Wines, Marie

1989-01-01

165

Commercialization of the land remote sensing system: An examination of mechanisms and issues  

NASA Technical Reports Server (NTRS)

In September 1982 the Secretary of Commerce was authorized (by Title II of H.R. 5890 of the 97th Congress) to plan and provide for the management and operation of the civil land remote sensing satellite systems, to provide for user fees, and to plan for the transfer of the ownership and operation of future civil operational land remote sensing satellite systems to the private sector. As part of the planning for transfer, a number of approaches were to be compared including wholly private ownership and operation of the system by an entity competitively selected, mixed government/private ownership and operation, and a legislatively-chartered privately-owned corporation. The results of an analysis and comparison of a limited number of financial and organizational approaches for either transfer of the ownership and operation of the civil operational land remote sensing program to the private sector or government retention are presented.

Cauley, J. K.; Gaelick, C.; Greenberg, J. S.; Logsdon, J.; Monk, T.

1983-01-01

166

Selecting landing sites for lunar lander missions using spatial analysis  

NASA Astrophysics Data System (ADS)

Russian Federal Space Agency (Roscosmos) is planning to launch two spacecrafts to the Moon with lander missions in 2015 and 2017. [1] Here, we present an approach to create a method of landing sites selection. We researched the physical features of the Moon using spatial analysis techniques presented in ArcGIS Desktop Software in accordance with its suitability for automatic landing. Hence we analyzed Russian lunar program and received the technical characteristics of the spacecrafts and scientific goals that they should meet [1]. Thus we identified the criteria of surface suitability for landing. We divided them into two groups: scientific criteria (the hydrogen content of the regolith [2] and day and night sur-face temperature [3]) and safety criteria (surface slopes and roughness, sky view factor, the Earth altitude, presence of polar permanently shadowed regions). In conformity with some investigations it is believed that the south polar region of the Moon is the most promising territory where water ice can be found (finding water ice is the main goal for Russian lunar missions [1]). According to the selected criteria and selected area of research we used remote sensing data from LRO (Lunar Reconnaissance Orbiter) [4] as basic data, because it is the most actual and easily available. The data was processed and analyzed using spatial analysis techniques of ArcGIS Desktop Software, so we created a number of maps depicting the criteria and then combined and overlaid them. As a result of overlay process we received five territories where the landing will be safe and the scientific goals will have being met. It should be noted that our analysis is only the first order assessment and the results cannot be used as actual landing sites for the lunar missions in 2015 and 2017, since a number of factors, which can only be analyzed in a very large scale, was not taken into account. However, an area of researching is narrowed to five territories, what can make the future research much easier. The analysis of these five areas in a large scale will be the subject of further research. References: [1] Mitrofanov I. G. et al. (2011) LPS XLII, Abstract #1798 [2] Mitrofanov I. G., et al. Hydrogen Mapping of the Lunar South Pole Using the LRO Neutron Detector Experiment LEND // Science vol. 330 2010, pp. 483-486 [3] Paige D.A. et al. (2011) LPS XLII, Abstract #2544 [4] Zuber M.T. et al. (2010) Space Sci. Rev., 150, 63-80

Djachkova, Maia; Lazarev, Evgeniy

167

Land-mobile satellite communication system  

NASA Technical Reports Server (NTRS)

A satellite communications system includes an orbiting communications satellite for relaying communications to and from a plurality of ground stations, and a network management center for making connections via the satellite between the ground stations in response to connection requests received via the satellite from the ground stations, the network management center being configured to provide both open-end service and closed-end service. The network management center of one embodiment is configured to provides both types of service according to a predefined channel access protocol that enables the ground stations to request the type of service desired. The channel access protocol may be configured to adaptively allocate channels to open-end service and closed-end service according to changes in the traffic pattern and include a free-access tree algorithm that coordinates collision resolution among the ground stations.

Yan, Tsun-Yee (Inventor); Rafferty, William (Inventor); Dessouky, Khaled I. (Inventor); Wang, Charles C. (Inventor); Cheng, Unjeng (Inventor)

1993-01-01

168

The KamLAND Full-Volume Calibration System  

SciTech Connect

We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.

KamLAND Collaboration; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A.; Elor, G.; Frank, A.; Freedman, S. J.; Fujikawa, B. K.; Galloway, M.; Gray, F.; Heeger, K. M.; Hsu, L.; Ichimura, K.; Kadel, R.; Keefer, G.; Lendvai, C.; McKee, D.; O'Donnell, T.; Piepke, A.; Steiner, H. M.; Syversrud, D.; Wallig, J.; Winslow, L. A.; Ebihara, T.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Owada, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Tamae, K.; Yoshida, S.; Kozlov, A.; Murayama, H.; Grant, C.; Leonard, D. S.; Luk, K.-B.; Jillings, C.; Mauger, C.; McKeown, R. D.; Zhang, C.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Piquemal, F.; Ricol, J.-S.

2009-03-05

169

Overview of the Phoenix Entry, Descent and Landing System Architecture  

NASA Technical Reports Server (NTRS)

NASA s Phoenix Mars Lander began its journey to Mars from Cape Canaveral, Florida in August 2007, but its journey to the launch pad began many years earlier in 1997 as NASA s Mars Surveyor Program 2001 Lander. In the intervening years, the entry, descent and landing (EDL) system architecture went through a series of changes, resulting in the system flown to the surface of Mars on May 25th, 2008. Some changes, such as entry velocity and landing site elevation, were the result of differences in mission design. Other changes, including the removal of hypersonic guidance, the reformulation of the parachute deployment algorithm, and the addition of the backshell avoidance maneuver, were driven by constant efforts to augment system robustness. An overview of the Phoenix EDL system architecture is presented along with rationales driving these architectural changes.

Grover, Myron R., III; Cichy, Benjamin D.; Desai, Prasun N.

2008-01-01

170

Intersects between Land, Energy, Water and the Climate System  

NASA Astrophysics Data System (ADS)

Climate change affects water, and land resources, and with growing human activity, each of these sectors relies increasingly on the others for critical resources. Events such as drought across the South Central U.S. during 2011 demonstrate that climatic impacts within each of these sectors can cascade through interactions between sectors. Energy, water, and land resources are each vulnerable to impacts on either of the other two sectors. For example, energy systems inherently require land and water. Increased electricity demands to contend with climate change can impose additional burdens on overly subscribed water resources. Within this environment, energy systems compete for water with agriculture, human consumption, and other needs. In turn, climate driven changes in landscape attributes and land use affect water quality and availability as well as energy demands. Diminishing water quality and availability impose additional demands for energy to access and purify water, and for land to store and distribute water. In some situations, interactions between water, energy, and land resources make options for reducing greenhouse gas emissions vulnerable to climate change. Energy options such as solar power or biofuel use can reduce net greenhouse gas emissions as well as U.S. dependence on foreign resources. As a result, the U.S. is expanding renewable energy systems. Advanced technology such as carbon dioxide capture with biofuels may offer a means of removing CO2 from the atmosphere. But as with fossil fuels, renewable energy sources can impose significant demands for water and land. For example, solar power mayrequire significant land to site facilities and water for cooling or to produce steam. Raising crops to produce biofuels uses arable land and water that might otherwise be available for food production. Thus, warmer and drier climate can compromise these renewable energy resources, and drought can stress water supplies creating competition between energy production and agriculture. These kinds of stresses often initiate innovated technological developments, such as dry cooling to reduce water demands in the U.S. Southwest for utility-scalesolar development, however, the need for large areas of land remain, and often, large land tracts in this region are under Federal ownership and used as conservation or wildlife refuges. Conflicting stakeholder views, institutional commitments, and international concerns can constrain options for reducing vulnerability to climate change, and interactions among water, energy, and land resource sectors can intensify such constraints. While management decisions may focus primarily on one of these resource sectors, where the three sectors are tightly coupled, options for mitigating or adapting to climate change may be limited more than expected. For example, the Columbia River Treaty between Canada and the U.S. emphasizes hydroelectric power and flood control, but with warmer temperatures and drier summers projected for the Northwest, diminishing water supplies will result in increased pumping for resource production (i.e., deeper groundwater) and transmission. Finally, coordinated water management for agriculture, ecosystem services, and hydropower will be an important aspect of adaptation not necessarily accommodated by the Treaty.

Hibbard, K. A.; Skaggs, R.; Wilson, T.

2012-12-01

171

Contextualising land grabbing: contemporary land deals, the global subsistence crisis and the world food system  

Microsoft Academic Search

This article analytically contextualises the spate of contemporary land deals popularly known as ‘land grabbing’ by locating such deals within the processes that simultaneously underpin the capitalist restructuring of global agriculture and deepen the global subsistence crisis. The article situates contemporary land deals within the context of recent rises in food prices, offers a precise definition of land grabbing and

A. Haroon Akram-Lodhi

2012-01-01

172

Systems Analysis Systems Integration  

E-print Network

to H2 not straightforward Exploratory research is essential Extensive R&D needed Issues: Economic any previously undertaken by DOE in civilian energy Systems Analysis essential guidance / perspective include coal liquids, shale oil & biomass. #12;7 OPTIONS FOR FUTURE U.S. ENERGY - MY VIEW Coal

173

VITS-A Vision System for Autonomous Land Vehicle Navigation  

Microsoft Academic Search

A description is given of VITS (for vision task sequencer), the vision system for the autonomous land vehicle (ALV) Alvin, addressing in particular the task of road-following. The ALV vision system builds symbolic descriptions of road and obstacle boundaries using both video and range sensors. The authors discuss various road segmentation methods for video-based road-following, along with approaches to boundary

MATTHEW A. TURK; David G. Morgenthaler; Keith D. Gremban; Martin Marra

1988-01-01

174

Video Guidance, Landing, and Imaging system (VGLIS) for space missions  

NASA Technical Reports Server (NTRS)

The feasibility of an autonomous video guidance system that is capable of observing a planetary surface during terminal descent and selecting the most acceptable landing site was demonstrated. The system was breadboarded and "flown" on a physical simulator consisting of a control panel and monitor, a dynamic simulator, and a PDP-9 computer. The breadboard VGLIS consisted of an image dissector camera and the appropriate processing logic. Results are reported.

Schappell, R. T.; Knickerbocker, R. L.; Tietz, J. C.; Grant, C.; Flemming, J. C.

1975-01-01

175

23 CFR 970.214 - Federal lands congestion management system (CMS).  

...false Federal lands congestion management system (CMS). 970.214 Section 970.214...HIGHWAYS NATIONAL PARK SERVICE MANAGEMENT SYSTEMS National Park Service Management Systems § 970.214 Federal lands congestion...

2014-04-01

176

23 CFR 973.208 - Indian lands pavement management system (PMS).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Indian lands pavement management system (PMS). 973.208...Systems § 973.208 Indian lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.” 1 1...

2012-04-01

177

23 CFR 970.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Federal lands pavement management system (PMS). 970.208...Systems § 970.208 Federal lands pavement management system (PMS). In addition... (i) An inventory of the physical pavement features including the number of...

2012-04-01

178

23 CFR 971.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Federal lands pavement management system (PMS). 971.208...Systems § 971.208 Federal lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.” 1 1...

2013-04-01

179

23 CFR 970.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Federal lands pavement management system (PMS). 970.208...Systems § 970.208 Federal lands pavement management system (PMS). In addition... (i) An inventory of the physical pavement features including the number of...

2013-04-01

180

23 CFR 971.208 - Federal lands pavement management system (PMS).  

...2014-04-01 false Federal lands pavement management system (PMS). 971.208...Systems § 971.208 Federal lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.” 1 1...

2014-04-01

181

23 CFR 970.208 - Federal lands pavement management system (PMS).  

...2014-04-01 false Federal lands pavement management system (PMS). 970.208...Systems § 970.208 Federal lands pavement management system (PMS). In addition... (i) An inventory of the physical pavement features including the number of...

2014-04-01

182

23 CFR 972.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Federal lands pavement management system (PMS). 972.208...Systems § 972.208 Federal lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.”2 2...

2013-04-01

183

23 CFR 973.208 - Indian lands pavement management system (PMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Indian lands pavement management system (PMS). 973.208...Systems § 973.208 Indian lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.” 1 1...

2013-04-01

184

23 CFR 972.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Federal lands pavement management system (PMS). 972.208...Systems § 972.208 Federal lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.”2 2...

2012-04-01

185

23 CFR 972.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Federal lands pavement management system (PMS). 972.208...Systems § 972.208 Federal lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.”2 2...

2011-04-01

186

23 CFR 973.208 - Indian lands pavement management system (PMS).  

...2014-04-01 false Indian lands pavement management system (PMS). 973.208...Systems § 973.208 Indian lands pavement management system (PMS). In addition...concepts described in the AASHTO's “Pavement Management Guide.” 1 1...

2014-04-01

187

23 CFR 970.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Federal lands pavement management system (PMS). 970.208...Systems § 970.208 Federal lands pavement management system (PMS). In addition... (i) An inventory of the physical pavement features including the number of...

2011-04-01

188

23 CFR 972.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Federal lands bridge management system (BMS). 972.210...Systems § 972.210 Federal lands bridge management system (BMS). In addition... (a) The FWS shall have a BMS for bridges which are under the FWS...

2012-04-01

189

23 CFR 972.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Federal lands bridge management system (BMS). 972.210...Systems § 972.210 Federal lands bridge management system (BMS). In addition... (a) The FWS shall have a BMS for bridges which are under the FWS...

2011-04-01

190

23 CFR 972.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Federal lands bridge management system (BMS). 972.210...Systems § 972.210 Federal lands bridge management system (BMS). In addition... (a) The FWS shall have a BMS for bridges which are under the FWS...

2013-04-01

191

23 CFR 973.212 - Indian lands safety management system (SMS).  

Code of Federal Regulations, 2012 CFR

...false Indian lands safety management system (SMS). 973.212 Section... FEDERAL LANDS HIGHWAYS MANAGEMENT SYSTEMS PERTAINING TO THE BUREAU OF... Bureau of Indian Affairs Management Systems § 973.212 Indian...

2012-04-01

192

23 CFR 973.212 - Indian lands safety management system (SMS).  

Code of Federal Regulations, 2013 CFR

...false Indian lands safety management system (SMS). 973.212 Section... FEDERAL LANDS HIGHWAYS MANAGEMENT SYSTEMS PERTAINING TO THE BUREAU OF... Bureau of Indian Affairs Management Systems § 973.212 Indian...

2013-04-01

193

CURENT LAND USE/LAND COVER ANALYSIS FOR COASTAL ALABAMA MX974176  

EPA Science Inventory

The project entails land use/land cover and classification of current LandSat 7 satellite imagery. The final products will include digital files for the classified imagery, an attributed vector polygon GIS coverage of classified areas in Arcview export and Arcview shapefile form...

194

Videometric terminal guidance method and system for UAV accurate landing  

NASA Astrophysics Data System (ADS)

We present a videometric method and system to implement terminal guidance for Unmanned Aerial Vehicle(UAV) accurate landing. In the videometric system, two calibrated cameras attached to the ground are used, and a calibration method in which at least 5 control points are applied is developed to calibrate the inner and exterior parameters of the cameras. Cameras with 850nm spectral filter are used to recognize a 850nm LED target fixed on the UAV which can highlight itself in images with complicated background. NNLOG (normalized negative laplacian of gaussian) operator is developed for automatic target detection and tracking. Finally, 3-D position of the UAV with high accuracy can be calculated and transfered to control system to direct UAV accurate landing. The videometric system can work in the rate of 50Hz. Many real flight and static accuracy experiments demonstrate the correctness and veracity of the method proposed in this paper, and they also indicate the reliability and robustness of the system proposed in this paper. The static accuracy experiment results show that the deviation is less-than 10cm when target is far from the cameras and lessthan 2cm in 100m region. The real flight experiment results show that the deviation from DGPS is less-than 20cm. The system implement in this paper won the first prize in the AVIC Cup-International UAV Innovation Grand Prix, and it is the only one that achieved UAV accurate landing without GPS or DGPS.

Zhou, Xiang; Lei, Zhihui; Yu, Qifeng; Zhang, Hongliang; Shang, Yang; Du, Jing; Gui, Yang; Guo, Pengyu

2012-06-01

195

Propeller modulation effects on a scanning beam microwave landing system  

NASA Technical Reports Server (NTRS)

An investigation to assess the modulation effects on microwave signals transmitted through rotating propeller blades. Interruption of the antenna line-of-sight signal by the rotating propeller causes a variation of path loss, which produces essentially an amplitude modulation of the received signal. This interruption or blockage effect is generally only partial because of edge diffraction around the particular interfering propeller blade. Signals reflected from the rotating propeller will also cause Doppler frequency shifts to be present in the received signals. A scanning beam microwave landing system (MLS) known as MODILS (modular instrument landing system) was used to process the received signals for display. The effects of propeller modulation were studied by varying the following parameters: (1) spacing between propeller and receiving antenna, (2) propeller dimensions, (3) propeller speed (rpm), (4) number of propeller blades, (5) system data rate, (6) receiver response time, and (7) receiver antenna aperture.

Pope, J. M.; Staehle, W. H.

1974-01-01

196

Modeling and Simulation of the Second-Generation Orion Crew Module Air Bag Landing System  

NASA Technical Reports Server (NTRS)

Air bags were evaluated as the landing attenuation system for earth landing of the Orion Crew Module (CM). An important element of the air bag system design process is proper modeling of the proposed configuration to determine if the resulting performance meets requirements. Analysis conducted to date shows that airbags are capable of providing a graceful landing of the CM in nominal and off-nominal conditions such as parachute failure, high horizontal winds, and unfavorable vehicle/ground angle combinations. The efforts presented here surround a second generation of the airbag design developed by ILC Dover, and is based on previous design, analysis, and testing efforts. In order to fully evaluate the second generation air bag design and correlate the dynamic simulations, a series of drop tests were carried out at NASA Langley's Landing and Impact Research (LandIR) facility. The tests consisted of a full-scale set of air bags attached to a full-scale test article representing the Orion Crew Module. The techniques used to collect experimental data, construct the simulations, and make comparisons to experimental data are discussed.

Timmers, Richard B.; Welch, Joseph V.; Hardy, Robin C.

2009-01-01

197

Development of a total landed cost and risk analysis model for global strategic sourcing  

E-print Network

Total landed cost and supply chain risk analysis are methods that many companies use to assess strategic sourcing decisions. For this project, landed cost is defined as those costs associated with material movement from a ...

Feller, Brian (Brian C.)

2008-01-01

198

Autonomous rendezvous, docking, and landing system using cruise missile technologies  

NASA Astrophysics Data System (ADS)

General Dynamics has been developing an Autonomous Rendezvous Docking and Landing (ARD&L) system that utilizes cruise missile technologies. In November 1990 the Autonomous Rendezvous and Docking (AR&D) system was first demonstrated for members of NASA's Strategic Avionics Technology Working Group (SATWG). This simulation utilized prototype hardware from the Cruise Missile and Advanced Centaur Avionics systems. The objective was to show that all the accuracy, reliability, and operational requirements established for a spacecraft to dock with Space Station Freedom could be met by the proposed system. Rapid prototyping techniques were used to evaluate the proposed system in a real time, hardware in the loop simulation of the rendezvous and docking reference mission. The simulation is currently being upgraded to test an Autonomous Approach and Landing (AA&L) system. Both systems use inertial guidance and control systems supplemented by the Global Positioning System (GPS) and an Image Processing System (IPS), for target recognition and tracking. The IPS includes a general purpose multiprocessor computer and a selected suite of sensors that will provide the required relative position and orientation data. Graphic displays can provide the astronaut/operator with realtime guidance and navigation data with enhanced video or sensor imagery.

Jones, Ruel E.

1992-07-01

199

Olive production systems on sloping land: prospects and scenarios.  

PubMed

The ultimate objective of the EU Olivero project was to improve the quality of life of the rural population and to assure the sustainable use of the natural resources of land and water in the sloping and mountainous olive production systems (SMOPS) areas in Southern Europe. One specific objective was to develop, with end-users, alternative future scenarios for olive orchards in the five Olivero target areas. This paper discusses the development of these scenarios, and their socio-economic and environmental effects. After presenting the different production systems (SMOPS) and their strengths, weaknesses, opportunities and threats, a general overview is given of the medium- and long-term prospects. These have been validated by experts from the olive sector and foresee changes towards abandonment, intensification and organic production. On balance, the changes could lead to lower production of some target areas in future. An analysis of major external factors affecting the future development of SMOPS indicates there will be labour shortages and increased wage rates, reduced subsidies and constant or rising olive oil prices. On the basis of these assumptions, four future scenarios are developed for the five target areas, with the help of a Linear Programming simulation model. The results are presented for two target areas. For the Trás-os-Montes target area in Portugal, three of the four tested scenarios point to a high level of abandonment, while in the most positive scenario the areas under semi-intensive low input and organic SMOPS increase. In the Granada and Jaen target area in Spain, all scenarios hint at intensification, and only the orchards on the steepest slopes are likely to be abandoned. The direction and extent of environmental effects (erosion, fire risk, pollution, water use and biodiversity) differ per scenario, as do the extent of cross-compliance and agri-environmental measures. PMID:17913332

de Graaff, Jan; Duran Zuazo, Victor-Hugo; Jones, Nádia; Fleskens, Luuk

2008-11-01

200

Pervasive transition of the Brazilian land-use system  

NASA Astrophysics Data System (ADS)

Agriculture, deforestation, greenhouse gas emissions and local/regional climate change have been closely intertwined in Brazil. Recent studies show that this relationship has been changing since the mid 2000s, with the burgeoning intensification and commoditization of Brazilian agriculture. On one hand, this accrues considerable environmental dividends including a pronounced reduction in deforestation (which is becoming decoupled from agricultural production), resulting in a decrease of ~40% in nationwide greenhouse gas emissions since 2005, and a potential cooling of the climate at the local scale. On the other hand, these changes in the land-use system further reinforce the long-established inequality in land ownership, contributing to rural-urban migration that ultimately fuels haphazard expansion of urban areas. We argue that strong enforcement of sector-oriented policies and solving long-standing land tenure problems, rather than simply waiting for market self-regulation, are key steps to buffer the detrimental effects of agricultural intensification at the forefront of a sustainable pathway for land use in Brazil.

Lapola, David M.; Martinelli, Luiz A.; Peres, Carlos A.; Ometto, Jean P. H. B.; Ferreira, Manuel E.; Nobre, Carlos A.; Aguiar, Ana Paula D.; Bustamante, Mercedes M. C.; Cardoso, Manoel F.; Costa, Marcos H.; Joly, Carlos A.; Leite, Christiane C.; Moutinho, Paulo; Sampaio, Gilvan; Strassburg, Bernardo B. N.; Vieira, Ima C. G.

2014-01-01

201

Assessing land-use impacts on biodiversity using an expert systems tool  

USGS Publications Warehouse

Habitat alteration, in the form of land-use development, is a leading cause of biodiversity loss in the U.S. and elsewhere. Although statutes in the U.S. may require consideration of biodiversity in local land-use planning and regulation, local governments lack the data, resources, and expertise to routinely consider biotic impacts that result from permitted land uses. We hypothesized that decision support systems could aid solution of this problem. We developed a pilot biodiversity expert systems tool (BEST) to test that hypothesis and learn what additional scientific and technological advancements are required for broad implementation of such a system. BEST uses data from the U.S. Geological Survey's Gap Analysis Program (GAP) and other data in a desktop GIS environment. The system provides predictions of conflict between proposed land uses and biotic elements and is intended for use at the start of the development review process. Key challenges were the development of categorization systems that relate named land-use types to ecological impacts, and relate sensitivities of biota to ecological impact levels. Although the advent of GAP and sophisticated desktop GIS make such a system feasible for broad implementation, considerable ongoing research is required to make the results of such a system scientifically sound, informative, and reliable for the regulatory process. We define a role for local government involvement in biodiversity impact assessment, the need for a biodiversity decision support system, the development of a prototype system, and scientific needs for broad implementation of a robust and reliable system.

Crist, P. J.; Kohley, T. W.; Oakleaf, J.

2000-01-01

202

Airborne antenna polarization study for the microwave landing system  

NASA Technical Reports Server (NTRS)

The feasibility of the microwave landing system (MLS) airborne antenna pattern coverage requirements are investigated for a large commercial aircraft using a single omnidirectional antenna. Omnidirectional antennas having vertical and horizontal polarizations were evaluated at several different station locations on a one-eleventh scale model Boeing 737 aircraft. The results obtained during this experimental program are presented which include principal plane antenna patterns and complete volumetric coverage plots.

Gilreath, M. C.

1976-01-01

203

23 CFR 972.210 - Federal lands bridge management system (BMS).  

...Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems § 972.210 Federal lands bridge management...

2014-04-01

204

23 CFR 972.212 - Federal lands safety management system (SMS).  

...Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems § 972.212 Federal lands safety management...

2014-04-01

205

23 CFR 972.208 - Federal lands pavement management system (PMS).  

...Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems § 972.208 Federal lands pavement management...

2014-04-01

206

23 CFR 972.214 - Federal lands congestion management system (CMS).  

...Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems § 972.214 Federal lands congestion management...

2014-04-01

207

A Global Land System Framework for Integrated Climate-Change Assessments  

E-print Network

Land ecosystems play a major role in the global cycles of energy, water, carbon and nutrients. A Global Land System (GLS) framework has been developed for the Integrated Global Systems Model Version 2 (IGSM2) to simulate ...

Schlosser, C. Adam

208

29 CFR 1915.507 - Land-side fire protection systems.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Land-side fire protection systems. 1915.507 Section...HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Fire Protection in Shipyard Employment § 1915.507 Land-side fire protection systems. (a) Employer...

2013-07-01

209

29 CFR 1915.507 - Land-side fire protection systems.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Land-side fire protection systems. 1915.507 Section...HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Fire Protection in Shipyard Employment § 1915.507 Land-side fire protection systems. (a) Employer...

2012-07-01

210

29 CFR 1915.507 - Land-side fire protection systems.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Land-side fire protection systems. 1915.507 Section...HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Fire Protection in Shipyard Employment § 1915.507 Land-side fire protection systems. (a) Employer...

2011-07-01

211

77 FR 50985 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...Implementation of the National Forest System Land Management Planning Rule AGENCY: Forest Service, USDA. ACTION: Notice...Implementation of the National Forest System Land Management Planning Rule will meet in Washington, DC. The...

2012-08-23

212

78 FR 9883 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...Implementation of the National Forest System Land Management Planning Rule AGENCY: Forest Service, USDA. ACTION: Notice...Implementation of the National Forest System Land Management Planning Rule will meet in Albuquerque, NM. The...

2013-02-12

213

75 FR 52713 - Nationwide Aerial Application of Fire Retardant on National Forest System Lands  

Federal Register 2010, 2011, 2012, 2013

...Service Nationwide Aerial Application of Fire Retardant on National Forest System Lands...continued nationwide aerial application of fire retardant on National Forest System lands...The Forest Service is working to restore fire-adapted ecosystems through...

2010-08-27

214

Theoretical analysis of the global land carbon cycle: what determines the trajectory of future carbon uptake?  

NASA Astrophysics Data System (ADS)

The global land surface has taken up about 29% of anthropogenic CO2 emissions since preindustrial times. Yet it remains uncertain whether this significant buffer to the effects of anthropogenic climate change will continue in future. Some models predict that the global land biosphere will remain a carbon sink by the end of this century, but others predict it to become a major source. It is therefore important to understand what causes this divergence in predictions. In this presentation, we combined numerical and mathematical analysis to reveal general behaviour of global land models. Our analysis is based on the recognition that the terrestrial carbon cycle generally can be mathematically expressed by a system of first-order linear ordinary differential equations subject to an initial condition as follows: dC/dt = x(t)AC+BU(t) with C(t=0)=C0 where C(t) is the C pool size, A is the C transfer matrix, U is the photosynthetic input, B is a vector of partitioning coefficients, C0 is the initial value of the C pool, and x is an environmental scalar. In this equation, the linear carbon transfer among pools within one ecosystem is represented by matrix A and vector B, and the nonlinearity of environmental influences is represented by environmental scalar x(t) on carbon transfer and U(t) for carbon influx. We investigate how important variation in parameters controlling terrestrial carbon cycling are for three key predictions of the dynamics of future land carbon: the maximum carbon uptake, Fmax, the number of years it takes to reach Fmax, tmax, and the year in which the land biosphere changes from a carbon sink to a source, t1 (if it happens). The parameters included the sensitivity of net primary production to atmospheric [CO2], ?, the temperature sensitivity of soil carbon decomposition, Q10, and the sensitivity of global mean land surface to atmospheric [CO2],?. Our theoretical analyses reveal that a theoretical maximal amount carbon accumulated by land biosphere can be estimated from Fmax and the residence times of the different carbon pools, and that an estimate on the time it takes for the system to approach its new equilibrium can be obtained from the residence time of the slowest pool. Our numerical analyses reveal that a 3-D parameter space can bound the range of land carbon uptake trajectories from 1850 to 2100 predicted by all Earth System Models for the 5th assessment report of the IPCC. The maximal amount of carbon accumulated, tmax and t1 increases with ? and decreases with Q10 and ?. The sensitivities of all three model predictions to ? and Q10 increase with ? .

Wang, Y.; Smith, M. J.; Luo, Y.; Leite, M.; Agusto, F.; Chen, B.; Hoffman, F. M.; Medlyn, B. E.; Rasmussen, M.

2013-12-01

215

Vision-Aided Inertial Navigation for Precise Planetary Landing: Analysis and Experiments  

Microsoft Academic Search

In this paper, we present the analysis and experi- mental validation of a vision-aided inertial navigation algorithm for planetary landing applications. The system employs tight integration of inertial and visual feature measurements to com- pute accurate estimates of the lander's terrain-relative position, attitude, and velocity in real time. Two types of features are considered: mapped landmarks, i.e., features whose global

Anastasios I. Mourikis; Nikolas Trawny; Stergios I. Roumeliotis; Andrew Johnson; Larry Matthies

2007-01-01

216

Modeling and Simulation of the Second-Generation Orion Crew Module Air Bag Landing System  

NASA Technical Reports Server (NTRS)

Air bags were evaluated as the landing attenuation system for earth landing of the Orion Crew Module (CM). Analysis conducted to date shows that airbags are capable of providing a graceful landing of the CM in nominal and off-nominal conditions such as parachute failure, high horizontal winds, and unfavorable vehicle/ground angle combinations, while meeting crew and vehicle safety requirements. The analyses and associated testing presented here surround a second generation of the airbag design developed by ILC Dover, building off of relevant first-generation design, analysis, and testing efforts. In order to fully evaluate the second generation air bag design and correlate the dynamic simulations, a series of drop tests were carried out at NASA Langley s Landing and Impact Research (LandIR) facility in Hampton, Virginia. The tests consisted of a full-scale set of air bags attached to a full-scale test article representing the Orion Crew Module. The techniques used to collect experimental data, develop the simulations, and make comparisons to experimental data are discussed.

Timmers, Richard B.; Hardy, Robin C.; Willey, Cliff E.; Welch, Joseph V.

2009-01-01

217

Interior Secretary Formally Designates BLM Lands the National System of Public Lands  

Microsoft Academic Search

He also said that the designation will emphasize the interconnectedness and interdependence of the public lands and all who benefit from them; better convey the diversity of interests and values associated with the public lands and how these are served through balanced, comprehensive, management; and increase the critical importance of enlightened citizen stewardship to the preservation of these lands and

Frank Quimby

2009-01-01

218

Improved Modeling of Land-Atmosphere Interactions using a Coupled Version of WRF with the Land Information System  

NASA Technical Reports Server (NTRS)

The exchange of energy and moisture between the Earth's surface and the atmospheric boundary layer plays a critical role in many hydrometeorological processes. Accurate and high-resolution representations of surface properties such as sea-surface temperature (SST), vegetation, soil temperature and moisture content, and ground fluxes are necessary to better understand the Earth-atmosphere interactions and improve numerical predictions of weather and climate phenomena. The NASA/NWS Short-term Prediction Research and Transition (SPORT) Center is currently investigating the potential benefits of assimilating high-resolution datasets derived from the NASA moderate resolution imaging spectroradiometer (MODIS) instruments using the Weather Research and Forecasting (WRF) model and the Goddard Space Flight Center Land Information System (LIS). The LIS is a software framework that integrates satellite and ground-based observational and modeled data along with multiple land surface models (LSMs) and advanced computing tools to accurately characterize land surface states and fluxes. The LIS can be run uncoupled to provide a high-resolution land surface initial condition, and can also be run in a coupled mode with WRF to integrate surface and soil quantities using any of the LSMs available in LIS. The LIS also includes the ability to optimize the initialization of surface and soil variables by tuning the spin-up time period and atmospheric forcing parameters, which cannot be done in the standard WRF. Among the datasets available from MODIS, a leaf-area index field and composite SST analysis are used to improve the lower boundary and initial conditions to the LIS/WRF coupled model over both land and water. Experiments will be conducted to measure the potential benefits from using the coupled LIS/WRF model over the Florida peninsula during May 2004. This month experienced relatively benign weather conditions, which will allow the experiments to focus on the local and mesoscale impacts of the high-resolution MODIS datasets and optimized soil and surface initial conditions. Follow-on experiments will examine the utility of such an optimized WRF configuration for more complex weather scenarios such as convective initiation. This paper will provide an overview of the experiment design and present preliminary results from selected cases in May 2004.

Case, Jonathan L.; LaCasse, Katherine M.; Santanello, Joseph A., Jr.; Lapenta, William M.; Petars-Lidard, Christa D.

2007-01-01

219

Continental-scale water and energy flux analysis and validation for North American Land Data Assimilation System project phase 2 (NLDAS-2): 2. Validation of model-simulated streamflow  

NASA Astrophysics Data System (ADS)

This is the second part of a study on continental-scale water and energy flux analysis and validation conducted in phase 2 of the North American Land Data Assimilation System project (NLDAS-2). The first part concentrates on a model-by-model comparison of mean annual and monthly water fluxes, energy fluxes and state variables. In this second part, the focus is on the validation of simulated streamflow from four land surface models (Noah, Mosaic, Sacramento Soil Moisture Accounting (SAC-SMA), and Variable Infiltration Capacity (VIC) models) and their ensemble mean. Comparisons are made against 28-years (1 October 1979-30 September 2007) of United States Geological Survey observed streamflow for 961 small basins and 8 major basins over the conterminous United States (CONUS). Relative bias, anomaly correlation and Nash-Sutcliffe Efficiency (NSE) statistics at daily to annual time scales are used to assess model-simulated streamflow. The Noah (the Mosaic) model overestimates (underestimates) mean annual runoff and underestimates (overestimates) mean annual evapotranspiration. The SAC-SMA and VIC models simulate the mean annual runoff and evapotranspiration well when compared with the observations. The ensemble mean is closer to the mean annual observed streamflow for both the 961 small basins and the 8 major basins than is the mean from any individual model. All of the models, as well as the ensemble mean, have large daily, weekly, monthly, and annual streamflow anomaly correlations for most basins over the CONUS, implying strong simulation skill. However, the daily, weekly, and monthly NSE analysis results are not necessarily encouraging, in particular for daily streamflow. The Noah and Mosaic models are useful (NSE > 0.4) only for about 10% of the 961 small basins, the SAC-SMA and VIC models are useful for about 30% of the 961 small basins, and the ensemble mean is useful for about 42% of the 961 small basins. As the time scale increases, the NSE increases as expected. However, even for monthly streamflow, the ensemble mean is useful for only 75% of the 961 small basins.

Xia, Youlong; Mitchell, Kenneth; Ek, Michael; Cosgrove, Brian; Sheffield, Justin; Luo, Lifeng; Alonge, Charles; Wei, Helin; Meng, Jesse; Livneh, Ben; Duan, Qingyun; Lohmann, Dag

2012-02-01

220

Unmanned Aircraft Systems for Monitoring Department of the Interior Lands  

NASA Astrophysics Data System (ADS)

Unmanned Aircraft Systems (UAS) technology is quickly evolving and will have a significant impact on Earth science research. The U.S. Geological Survey (USGS) is conducting an operational test and evaluation of UAS to see how this technology supports the mission of the Department of the Interior (DOI). Over the last 4 years, the USGS, working with many partners, has been actively conducting proof of concept UAS operations, which are designed to evaluate the potential of UAS technology to support the mandated DOI scientific, resource and land management missions. UAS technology is being made available to monitor environmental conditions, analyze the impacts of climate change, respond to natural hazards, understand landscape change rates and consequences, conduct wildlife inventories and support related land management and law enforcement missions. Using small UAS (sUAS), the USGS is able to tailor solutions to meet project requirements by obtaining very high resolution video data, acquiring thermal imagery, detecting chemical plumes, and generating digital terrain models at a fraction of the cost of conventional surveying methods. UAS technology is providing a mechanism to collect timely remote sensing data at a low cost and at low risk over DOI lands that can be difficult to monitor and consequently enhances our ability to provide unbiased scientific information to better enable decision makers to make informed decisions. This presentation describes the UAS technology and infrastructure being employed, the application projects already accomplished, lessons learned and future of UAS within the DOI. We fully expect that by 2020 UAS will emerge as a primary platform for all DOI remote sensing applications. Much like the use of Internet technology, Geographic Information Systems (GIS) and Global Positioning Systems (GPS), UAS have the potential of enabling the DOI to be better stewards of the land.

Hutt, M. E.; Quirk, B.

2013-12-01

221

77 FR 8895 - Public Land Order No. 7788; Withdrawal of National Forest System Land for the Red Cloud...  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land for the Red Cloud Campground; New Mexico AGENCY: Bureau...historical interpretive integrity of the Red Cloud Campground within the Cibola National Forest...investment expended to develop the Red Cloud Campground facility and the unique...

2012-02-15

222

23 CFR 973.210 - Indian lands bridge management system (BMS).  

Code of Federal Regulations, 2010 CFR

... Indian lands bridge management system (BMS). In...Guidelines for Bridge Management Systems.” 2 2 “Guidelines for Bridge Management Systems,” AASHTO...procedure for applying network level analytical...

2010-04-01

223

Microwave landing system modeling with application to air traffic control  

NASA Technical Reports Server (NTRS)

Compared to the current instrument landing system, the microwave landing system (MLS), which is in the advanced stage of implementation, can potentially provide significant fuel and time savings as well as more flexibility in approach and landing functions. However, the expanded coverage and increased accuracy requirements of the MLS make it more susceptible to the features of the site in which it is located. An analytical approach is presented for evaluating the multipath effects of scatterers that are commonly found in airport environments. The approach combines a multiplane model with a ray-tracing technique and a formulation for estimating the electromagnetic fields caused by the antenna array in the presence of scatterers. The model is applied to several airport scenarios. The reduced computational burden enables the scattering effects on MLS position information to be evaluated in near real time. Evaluation in near real time would permit the incorporation of the modeling scheme into air traffic control automation; it would adaptively delineate zones of reduced accuracy within the MLS coverage volume, and help establish safe approach and takeoff trajectories in the presence of uneven terrain and other scatterers.

Poulose, M. M.

1991-01-01

224

A long-term forecast analysis on worldwide land uses.  

PubMed

More and more lands worldwide are being cultivated for food production while forests are disappearing at an unprecedented rate. This paper aims to make a long-term forecast on land uses worldwide and provide the public, researchers, and government officials with a clear profile for land uses in the future. Data of land uses since 1961 were used to fit historical trajectories and make the forecast. The results show that trajectories of land areas can be well fitted with univariate linear regressions. The forecasts of land uses during the coming 25 years were given in detail. Areas of agricultural land, arable land, and permanent pasture land worldwide would increase by 6.6%, 7.2%, and 6.3% respectively in the year 2030 as compared to the current areas. Permanent crops land area all over the world is forecasted to increase 0.64% by 2030. By the year 2030 the areas of forests and woodland, nonarable and nonpermanent land worldwide would decrease by 2.4% and 0.9% against the current areas. All other land area in the world would dramatically decline by 6.4% by the year 2030. Overall the land area related to agriculture would tend to decrease in developed countries, industrialized countries, Europe, and North and Central America. The agriculture related land area would considerably increase in developing countries, least developed countries, low-income countries, Asia, Africa, South America, etc. Developing countries hold larger total land area than developed countries. Dramatic and continuous growth in agricultural land area of developing countries would largely contribute to the expected growth of world agricultural land area in the coming years. Population explosion, food shortage and poverty in the world, especially in developing countries, together caused the excessive cultivation of land for agricultural uses in the past years. Increasing agricultural land area exacerbates the climate changes and degradation of environment. How to limit the growth of human population is a key problem for reducing agricultural land expansion. Development and use of high-yielding and high-quality crop and animal varieties, diversification of human food sources, and technical and financial assistance to developing countries from developed countries, should also be implemented and strengthened in the future in order to slow down or even reverse the increase trend of agricultural land area. Sustainable agriculture is the effective way to stabilize the agricultural land area without food shortage. Through various techniques and measures, sustainable agriculture may meet the food production goals with minimum environmental risk. Public awareness and interest in sustainable agriculture will help realize and ease the increasing stress from agricultural land expansion. PMID:16741808

Zhang, Wenjun; Qi, Yanhong; Zhang, Zhiguo

2006-08-01

225

Evolution of INMARSAT systems and applications: The land mobile experience  

NASA Technical Reports Server (NTRS)

Inmarsat has provided mobile satellite communication services for land mobile applications for well over a decade. Having started with the Inmarsat-A voice and telex system, Inmarsat is committed to the evolution of services towards a global personal, handheld satellite communicator. Over the years, users have benefitted from the evolution of technologies, increased user friendliness and portability of terminals and ever decreasing cost of operations. This paper describes the various present systems, their characteristics and applications, and outlines their contributions in the evolution towards the personal global communicator.

Staffa, Eugene; Subramaniam, Ram

1993-01-01

226

Precipitation, Recycling, and Land Memory: An Integrated Analysis  

E-print Network

A synthesis of several approaches to quantifying land–atmosphere interactions is presented. These approaches use data from observations or atmospheric reanalyses applied to atmospheric tracer models and stand-alone land ...

Dirmeyer, Paul A.

227

Applying a Model to Predict the Location of Land Drained by Subsurface Drainage Systems in Central Minnesota  

Microsoft Academic Search

Agricultural drain tile systems are a significant influence on the condition of wetlands and waterways. The influence of these systems is often difficult to determine since installation records are incomplete or were never kept. Using a modified decision class tree and raster analysis in ArcGIS, a model for predicting the location of land drained by subsurface systems was evaluated. The

Derrick Chip Brown

228

Using the Nordic Geodetic Observing System for land uplift studies  

NASA Astrophysics Data System (ADS)

Geodetic observing systems have been planned and developed during the last decade. An ideal observing system consists of a network of geodetic observing stations with several techniques at the same site, publicly accessible databases, and as a product delivers data time series, combination of techniques or some other results obtained from the data sets. Globally, there is the International Association of Geodesy (IAG) Global Geodetic Observing System (GGOS), and there are ongoing attempts to create also regional observing systems. In this paper we introduce one regional system, the Nordic Geodetic Observing System (NGOS) hosted by the Nordic Geodetic Commission (NKG). Data availability and accessibility are one of the major issues today. We discuss in general data-related topics, and introduce a pilot database project of NGOS. As a demonstration of the use of such a database, we apply it for postglacial rebound studies in the Fennoscandian area. We compare land uplift values from three techniques, GNSS, tide gauges and absolute gravity, with the Nordic Geodetic Commission NKG2005LU land uplift model for Fennoscandia. The purpose is to evaluate the data obtained from different techniques and different sources and get the most reliable values for the uplift using publicly available data. The primary aim of observing systems will be to produce data and other products needed by multidisciplinary projects, such as Upper Mantle Dynamics and Quaternary Climate in Cratonic Areas (DynaQlim) or the European Plate Observing System (EPOS), but their needs may currently exceed the scope of an existing observing system. We discuss what requirements the projects pose to observing systems and their development. To make comparisons between different studies possible and reliable, the researcher should document what they have in detail, either in appendixes, supplementary material or some other available format.

Nordman, M.; Poutanen, M.; Kairus, A.; Virtanen, J.

2014-07-01

229

Developing Lunar Landing Vehicle Display Requirements through Content Analysis of Apollo Lunar Landing Voice Communications  

E-print Network

The lengthy period since the Apollo landings limits present-day engineers attempting to draw from the experiences of veteran Apollo engineers and astronauts in the design of a new lunar lander. In order to circumvent these ...

Smith, C. A.

2008-01-01

230

Development of land based radar polarimeter processor system  

NASA Astrophysics Data System (ADS)

The processing subsystem of a land based radar polarimeter was designed and constructed. This subsystem is labeled the remote data acquisition and distribution system (RDADS). The radar polarimeter, an experimental remote sensor, incorporates the RDADS to control all operations of the sensor. The RDADS uses industrial standard components including an 8-bit microprocessor based single board computer, analog input/output boards, a dynamic random access memory board, and power supplis. A high-speed digital electronics board was specially designed and constructed to control range-gating for the radar. A complete system of software programs was developed to operate the RDADS. The software uses a powerful real time, multi-tasking, executive package as an operating system. The hardware and software used in the RDADS are detailed. Future system improvements are recommended.

Kronke, C. W.; Blanchard, A. J.

1983-09-01

231

Carbon balances during land conversion in early bioenergy systems  

NASA Astrophysics Data System (ADS)

In this study, we established a field experiment and deployed seven eddy-covariance towers to quantify the roles of land use change and the subsequent carbon (C) balances of three different bioenergy systems (corn, switchgrass, and mixed prairie species) that were developed from two historical land use types: monocultural grasslands dominated by smooth brome (Bromus inermis Leyss) and lands in the Conservation Reserve Program (CRP). Three CRP fields and three cropland fields were converted to soybean in 2009 (conversion year) before establishing the cellulosic biofuel cropping systems in 2010 (establishment year). A CRP perennial grassland site was kept undisturbed as a reference. Conversion of CRP to soybean induced net C emissions during the conversion year (134 -262 g C m-2 yr-1), while in the same year the net C balance at the CRP grassland reference was -35 g C m-2 yr-1 (i.e., net C sequestration). The establishment of switchgrass and mixed prairie induced a cumulative C balance of -113 g C m-2 (switchgrass from CRP), 250 g C m-2 (switchgrass from cropland), 706 g C m-2 (mixed prairie from CRP), and 59 g C m-2 (mixed prairie from cropland) over the three-year study period. The cumulative three-year C balance of corn converted from CRP and from cropland was -151 g C m-2 and -183 g C m-2, respectively. Eddy flux measurements during cellulosic biofuel crop establishment reveal annual changes in C balance that cannot be detected using conventional mass balance approaches. When end-use of harvested biomass was considered, the C balances for all studied systems, except the reference site, exhibited large C emissions ranging from 150 to 990 g C m-2 over the three-year conversion phase.

Zenone, T.; Chen, J.; Gelfand, I.; Robertson, G. P.; Hamilton, S. K.

2012-12-01

232

Land-use change analysis in Yulin prefecture, northwestern China using remote sensing and GIS  

Microsoft Academic Search

Rapid land-use change has taken place in many arid and semi-arid regions of China such as Yulin prefecture over the last decade due to rehabilitation measures. In this paper, land-use change dynamics were investigated by the combined use of satellite remote sensing and geographical information systems (GIS). Our objectives were to determine land-use transition rates among land-use types in Yulin

Z. Li; X. Li; Y. Wang; A. Ma; J. Wang

2004-01-01

233

Entry descent and landing systems for future missions  

NASA Astrophysics Data System (ADS)

In 2005, the Huygens probe, designed by Thales Alenia Space, France, successfully completed its entry and descent in Titan's atmosphere. In the frame of the Aurora Exploration Program, ESA has initiated industrial studies for the ExoMars mission. The Thales Alenia Space France-led consortium was awarded the contract for the design, development and manufacturing of the Entry and Descent System under Thales Alenia Space—Italy mission prime. Huygens and ExoMars constitute major European milestones in the field of atmospheric entry and descent. Eight out of the ten bodies larger than Mercury in the Solar System have a significant atmosphere to descent in, either to reach a solid surface, or to explore the atmosphere itself. The gained experience in Entry Descent and Landing design will enhance European industry capability to contribute to future planetary exploration missions. This paper assesses the different environments and conditions that Entry Descent and Landing Systems will meet. It discusses how Europe's Huygens and ExoMars experience will apply in such environments and identifies the critical technologies needed to complement it. It concludes on the elements of a roadmap for the related technological development.

Poncy, J.; Lebleu, D.; Arfi, P.; Schipper, A. M.

2010-07-01

234

Simulated final approach path captures using the microwave landing system  

NASA Technical Reports Server (NTRS)

Computer simulation results are presented for intercepting final approach paths using various Microwave Landing System (MLS) path capture concepts. This study, conducted under the Advanced Transport Operating System (ATOPS) program, simulated these captures using the MD-80 aircraft as the study model. Several different capture concepts were investigated. Systems that could be retrofitted into existing aircraft with minimum hardware and software changes were considered. An enhanced ILS look-alike capture provided improved tracking performance over conventional ILS without using a full-up path computer. The other concepts used waypoint databases and path computers to provide smart captures. These captures included lateral path intercepts as well as vertical path control. Winds, turbulence, and MLS noise were included in the simulation. In all cases, acceptable tracking errors were obtained during transition to the final approach path.

Feather, J. B.

1988-01-01

235

Surface Hydrology in Global River Basins in the Off-Line Land-Surface GEOS Assimilation (OLGA) System  

NASA Technical Reports Server (NTRS)

Land surface hydrology for the Off-line Land-surface GEOS Analysis (OLGA) system and Goddard Earth Observing System (GEOS-1) Data Assimilation System (DAS) has been examined using a river routing model. The GEOS-1 DAS land-surface parameterization is very simple, using an energy balance prediction of surface temperature and prescribed soil water. OLGA uses near-surface atmospheric data from the GEOS-1 DAS to drive a more comprehensive parameterization of the land-surface physics. The two global systems are evaluated using a global river routing model. The river routing model uses climatologic surface runoff from each system to simulate the river discharge from global river basins, which can be compared to climatologic river discharge. Due to the soil hydrology, the OLGA system shows a general improvement in the simulation of river discharge compared to the GEOS-1 DAS. Snowmelt processes included in OLGA also have a positive effect on the annual cycle of river discharge and source runoff. Preliminary tests of a coupled land-atmosphere model indicate improvements to the hydrologic cycle compared to the uncoupled system. The river routing model has provided a useful tool in the evaluation of the GCM hydrologic cycle, and has helped quantify the influence of the more advanced land surface model.

Bosilovich, Michael G.; Yang, Runhua; Houser, Paul R.

1998-01-01

236

LINEAR COVARIANCE ANALYSIS FOR LUNAR POWERED DESCENT AND LANDING NAVIGATION  

Microsoft Academic Search

Linear covariance analysis is a statistical analysis tool that produces Monte Carlo-like results in a fraction of the time. Because of its speed, it is often the tool of choice when there are many options and trades to be considered in the early design phases of a GN&C system. In this analysis, a baseline sensor suite consisting of a star-camera,

D. Geller

237

Carbon-Structural Analysis of Global Land Models (C-SALM)  

NASA Astrophysics Data System (ADS)

Abstract Better understanding of terrestrial carbon cycle is taking an increased scientific attention in the present era of climate change. Representation of the global carbon cycle is increasingly becoming complex in land models which results in large uncertainties in modeled outputs. Therefore, it is urgent to promote methods for quantitative and critical assessment of the models. Here we apply a systematic computational framework for Carbon-Structural Analysis of Global Land Model (C-SALM). The models used in this study are NCAR's Community Land Models (versions CLM3.5, CLM4.0 and CLM4.5) present in Community Earth System Model (CESM), Australian Community Atmosphere Biosphere Land Exchange (CABLE) and Common Land Model (CoLM) of China. The framework applied in this study facilitates the effective model comparison by decomposing a complex land model into traceable components based on fundamental properties of biogeochemical processes implemented in these models. The framework defines ecosystem carbon storage capacity (Xss) as a product of net primary productivity (NPP) and ecosystem residence time (?E). The ?E is determined by (i) baseline carbon residence times (??E), (ii) environmental scalars (?), and (iii) environmental forcings (Xia et al., 2013). The ??E can be further traced by partitioning coefficients (called vector B) and transfer coefficients (called A & C matrices) of NPP. To compare land models, the steady state annual average outputs were computed using 1990 forcing data at 1x1o resolution. The carbon storage capacity of each model was found to be determined differently which are due to differences present in carbon residence time and environmental scalars. The dependency of ? was assessed based on temperature (?T) and water (?W) scalars. This study explains the carbon model pool structure for each model and identifies the A, B and C elements at each carbon pool. The C-SALM study also evaluates models at major plant functional types (PFTs) level and traces major differences in terms of ?E, ??E and ? in each model. Climate forcings which control decomposition rates were found to be different at PFT level for each model. The approximation errors raised due to temporal variations of A, B, C and ? were evaluated at PFT level for each model. Information from C-SALM is helpful in enhancing the understanding of land model performance and reducing uncertainty in model output. Furthermore, this study has a range of implications for future model development and inter-comparison. Reference: Xia J, Luo Y, Wang YP, Hararuk O (2013) Traceable components of terrestrial carbon storage capacity in biogeochemical models. Global Change Biology, 19, 2104-2116.

Rafique, R.; Xia, J.; Hararuk, O.; Luo, Y.; Dai, Y.; Macaulay, C.

2013-12-01

238

Nitrogen leaching losses from a wastewater land application system.  

PubMed

Potential contamination of groundwater because of nitrogen leaching has been an important concern in municipal wastewater land application systems; however, few efforts have made to measure nitrogen leaching (total N, NO(3-)-N, and NH(4+)-N) under field conditions. This research successfully developed a conceptual nitrogen mass balance model and quantified its components at a wastewater land application system located at the City of Littlefield, Texas, from October 2005 to September 2007. The concentrations of total nitrogen and nitrate-nitrogen in the leachate were significantly less than 10 mg/L, therefore, there was no potential nitrogen contamination to groundwater found at this site during the research period. Linear regression models were analyzed and resulted in R2 values of 0.918, 0.966, and 0.833 between cumulative applied total nitrogen mass and cumulative leached total nitrogen mass, cumulative applied nitrate-nitrogen mass and cumulative leached nitrate-nitrogen mass, and cumulative applied ammonia-nitrogen mass and cumulative leached ammonia-nitrogen mass, respectively. The nitrogen mass balance design approach for this site resulted in significant nitrogen removal. Organic nitrogen may leach with other forms of nitrogen, and denitrification plays an important role in nitrogen removal during the winter and spring seasons when the grass is dry. PMID:20369566

Duan, Runbin; Fedler, Clifford B; Sheppard, Christopher D

2010-03-01

239

Air traffic control using a microwave landing system  

NASA Technical Reports Server (NTRS)

The performance of air traffic controllers using a simulated microwave landing system to control the landing of STOL aircraft is investigated. In a series of two experiments, controllers were asked to achieve a 60-sec separation between targets at the missed approach point when only two targets were on the simulated radar scope, and in the presence of 25 targets, with up to 10 on the screen at any one time. In both experiments, the presence of a ground wind is found to degrade separation performance, and an increased work load results in even greater separation variability, as the controllers did not have time to convert aircraft distances into times. In addition, curved courses are found to have an effect on performance. It is thus recommended that in order to create a practical air traffic control system with separation standards based on time, as in the MLS, controller work loads should be reduced and aircraft positions should be displayed with respect to time rather than distance.

Gershzohn, G.

1980-01-01

240

Navigation for space shuttle approach and landing using an inertial navigation system augmented by data from a precision ranging system or a microwave scan beam landing guidance system  

NASA Technical Reports Server (NTRS)

A preliminary study has been made of the navigation performance which might be achieved for the high cross-range space shuttle orbiter during final approach and landing by using an optimally augmented inertial navigation system. Computed navigation accuracies are presented for an on-board inertial navigation system augmented (by means of an optimal filter algorithm) with data from two different ground navigation aids; a precision ranging system and a microwave scanning beam landing guidance system. These results show that augmentation with either type of ground navigation aid is capable of providing a navigation performance at touchdown which should be adequate for the space shuttle. In addition, adequate navigation performance for space shuttle landing is obtainable from the precision ranging system even with a complete dropout of precision range measurements as much as 100 seconds before touchdown.

Mcgee, L. A.; Smith, G. L.; Hegarty, D. M.; Merrick, R. B.; Carson, T. M.; Schmidt, S. F.

1970-01-01

241

BAE systems brownout landing aid system technology (BLAST) system overview and flight test results  

NASA Astrophysics Data System (ADS)

Rotary wing aircraft continue to experience mishaps caused by the loss of visual situational awareness and spatial disorientation due to brownout or whiteout in dusty, sandy or snowy conditions as the downwash of the rotor blades creates obscurant clouds that completely engulf the helicopter during approaches to land. BAE Systems has developed a "see-through" brownout landing aid system technology (BLAST) based on a small and light weight 94GHz radar with proven ability to penetrate dust, coupled with proprietary antenna tracking, signal processing and digital terrain morphing algorithms to produce a cognitive real-time 3D synthetic image of the ground and proximate surface hazards in and around the landing zone. A series of ground and flight tests have been conducted at the United States Army's Yuma Proving Ground in Arizona that reflect operational scenarios in relevant environments to progressively mature the technology. A description of the BLAST solution developed by BAE Systems and results from recent flight tests is provided.

Sykora, Brian

2012-06-01

242

Spectral behavior of the coupled land-atmosphere system  

E-print Network

The main objective of this thesis is to understand the daily cycle of the energy coupling between the land and the atmosphere in response to a forcing of incoming radiation at their common boundary, the land surface. This ...

Gentine, Pierre

2010-01-01

243

A land surface soil moisture data assimilation system based on the dual-UKF method and the Community Land Model  

E-print Network

A land surface soil moisture data assimilation system based on the dual-UKF method system for assimilating satellite observations of soil moisture. Experiments for two sites in north-based methods in reproducing the temporal evolution of daily soil moisture, especially under freezing conditions

Dai, Aiguo

244

Use of South American Land Data Assimilation System (SALDAS) to Assess Impacts of Biofuel Expansion on Water Resources in Brazil  

NASA Astrophysics Data System (ADS)

Large scale expansion of sugarcane production in Brazil is very positive in terms of biofuels and greenhouse gases; however, potential impacts on water resources are uncertain. The objective of this analysis is to assess potential impacts of biofuel expansion in Central South Brazil on water resources using the South American Land Data Assimilation System (SALDAS). SALDAS is driven by 3 hourly atmospheric forcing. Limited surface observations have resulted in use of remotely sensed data merged with surface observations to calculate precipitation and shortwave radiation fields. SALDAS simulates partitioning of water and energy in response to spatiotemporal variability in climate forcing and land use change related to biofuel expansion. The impacts of land use changes related to biofuel expansion will be examined by evaluating water and energy fluxes in areas of different land use and substituting space for time. Output from SALDAS will be compared with coarser resolution Global Land Data Assimilation System (GLDAS) and other more traditional modeling approaches, such as CROPWAT, to estimate changes in water use from biofuel expansion. Land surface models provide an excellent reconnaissance tool to better understand the hydrology of regional systems in response to climate and land use in data constrained regions.

Goncalves, L.; De Mattos, J. Z.; Scarpare, F.; Galdos, M. V.; Scanlon, B.; Long, D.

2013-12-01

245

Land-Based Mobile Laser Scanning Systems: a Review  

NASA Astrophysics Data System (ADS)

Mobile mapping has been using various photogrammetric techniques for many years. In recent years, there has been an increase in the number of mobile mapping systems using laser scanners available in the market, partially because of the improvement in GNSS/INS performance for direct georeferencing. In this article, some of the most important land-based mobile laser scanning (MLS) systems are reviewed. Firstly, the main characteristics of MLS systems vs. airborne (ALS) and terrestrial laser scanning (TLS) systems are compared. Secondly, a short overview of the mobile mapping technology is also provided so that the reader can fully grasp the complexity and operation of these devices. As we put forward in this paper, a comparison of different systems is briefly carried out regarding specifications provided by the manufacturers. Focuses on the current research are also addressed with emphasis on the practical applications of these systems. Most of them have been utilized for data collection on road infrastructures or building façades. This article shows that MLS technology is nowadays well established and proven, since the demand has grown to the point that there are several systems suppliers offering their products to satisfy this particular market.

Puente, I.; González-Jorge, H.; Arias, P.; Armesto, J.

2011-09-01

246

Geospatial Analysis of Renewable Energy Technical Potential on Tribal Lands  

SciTech Connect

This technical report uses an established geospatial methodology to estimate the technical potential for renewable energy on tribal lands for the purpose of allowing Tribes to prioritize the development of renewable energy resources either for community scale on-tribal land use or for revenue generating electricity sales.

Doris, E.; Lopez, A.; Beckley, D.

2013-02-01

247

A Summary of the Development of a Nominal Land Landing Airbag Impact Attenuation System for the Orion Crew Module  

NASA Technical Reports Server (NTRS)

Airborne Systems North America (formally Irvin Aerospace Inc) has developed an Airbag Landing System for the Orion Crew Module of the Crew Exploration Vehicle. This work is in support of the NASA Langley Research Center Landing System Advanced Development Project. Orion is part of the Constellation Program to send human explorers back to the moon, and then onwards to Mars and other destinations in the Solar System. A component of the Vision for Space Exploration, Orion is being developed to also enable access to space following the retirement of the Space Shuttle in the next decade. This paper documents the development of a conceptual design, fabrication of prototype assemblies, component level testing and two generations of airbag landing system testing. The airbag system has been designed and analyzed using the transient dynamic finite element code LS-DYNA(RegisteredTradeMark). The landing system consists of six airbag assemblies; each assembly comprising a primary impact venting airbag and a non-venting anti-bottoming airbag. The anti-bottoming airbag provides ground clearance following the initial impact attenuation sequence. Incorporated into each primary impact airbag is an active vent that allows the entrapped gas to exit the control volume. The size of the vent is tailored to control the flow-rate of the exiting gas. An internal shaping structure is utilized to control the shape of the primary or main airbags prior to ground impact; this significantly improves stroke efficiency and performance.

Tutt, Ben; Gill, Susannah; Wilson, Aaron; Johnson, Keith

2009-01-01

248

Application of Calspan pitch rate control system to the Space Shuttle for approach and landing  

NASA Technical Reports Server (NTRS)

A pitch rate control system designed for use in the shuttle during approach and landing was analyzed and compared with a revised control system developed by NASA and the existing OFT control system. The design concept control system uses filtered pitch rate feedback with proportional plus integral paths in the forward loop. Control system parameters were designed as a function of flight configuration. Analysis included time and frequency domain techniques. Results indicate that both the Calspan and NASA systems significantly improve the flying qualities of the shuttle over the OFT. Better attitude and flight path control and less time delay are the primary reasons. The Calspan system is preferred because of reduced time delay and simpler mechanization. Further testing of the improved flight control systems in an in-flight simulator is recommended.

Weingarten, N. C.; Chalk, C. R.

1983-01-01

249

Analysis of Land Use/Land Cover Changes Using Remote Sensing Data and GIS at an Urban Area, Tirupati, India  

PubMed Central

Land use/land cover (LU/LC) changes were determined in an urban area, Tirupati, from 1976 to 2003 by using Geographical Information Systems (GISs) and remote sensing technology. These studies were employed by using the Survey of India topographic map 57 O/6 and the remote sensing data of LISS III and PAN of IRS ID of 2003. The study area was classified into eight categories on the basis of field study, geographical conditions, and remote sensing data. The comparison of LU/LC in 1976 and 2003 derived from toposheet and satellite imagery interpretation indicates that there is a significant increase in built-up area, open forest, plantation, and other lands. It is also noted that substantial amount of agriculture land, water spread area, and dense forest area vanished during the period of study which may be due to rapid urbanization of the study area. No mining activities were found in the study area in 1976, but a small addition of mining land was found in 2003. PMID:23781152

Mallupattu, Praveen Kumar; Sreenivasula Reddy, Jayarama Reddy

2013-01-01

250

Analysis of coastal change in Marie Byrd Land and Ellsworth Land, West Antarctica, using Landsat imagery  

USGS Publications Warehouse

The U.S. Geological Survey is using Landsat imagery from the early 1970s and mid- to late 1980s/early 1990s to analyze glaciological features, compile a glacier inventory, measure surface velocities of outlet glaciers, ice streams and ice shelves, determine coastline change and calculate the area and volume of iceberg calving in Antarctica. Ice-surface velocities in Marie Byrd and Ellsworth Lands, West Antarctica, range from the fast-moving Thwaites, Pine Island, Land and DeVicq Glaciers to the slower-moving ice shelves. The average ice-front velocity during the time interval of Landsat imagery, for the faster-moving outlet glaciers, was 2.9 km a-1 for Thwaites Glacier, 2.4 km a-1 for Pine Island Glacier, 2.0 km a-1 for Land Glacier and 1.4 km a-1 for DeVicq Glacier. Evaluation of coastal change from the early 1970s to the early 1990s shows advance of the floating ice front in some coastal areas and recession in others, with an overall small average advance in the entire coastal study area, but no major trend towards advance or retreat. Comparison of average ice-surface velocities with changes in the ice front has yielded estimates of iceberg calving. The total iceberg calving from the Marie Byrd Land and Ellsworth Land coasts during the study period was greater than 8500 km2 (estimated volume of about 2400 km3) or an average of about 550 km2 a-1 (more than 150 km3 a-1). Almost 70% of this discharge is contributed by Thwaites and Pine Island Glaciers.

Ferrigno, J.G.; Williams, R.S., Jr.; Rosanova, C.E.; Lucchitta, B.K.; Swithinbank, C.

1998-01-01

251

Orion Crew Module Landing System Simulation and Verification  

NASA Technical Reports Server (NTRS)

NASA Langley Research Center (LaRC) has developed a comprehensive test and analysis program to evaluate the ability of LS-DYNA to model the materials and the phenomena involved in soil and water landing impacts of the Orion crew module. Elemental, scale boilerplate, and full-scale prototype testing is being conducted in support of the simulation verification and validation approach. Aspects of the simulations evaluated against test data include soil constitutive properties, water equations of state, and contact algorithms. Subsystems tested include airbags, crushable energy absorbing honeycomb materials, and energy absorbing seat support struts. The procedures, instrumentation, and general observations from each test series are presented. Plans for a series of swing tests of a full-scale boilerplate into a purpose-built water basin are described. Further plans for swing tests of flight-like prototypes into the water basin are noted.

Vassilakos, Gregory J.; Stegall, David E.; Hardy, Robin C.; Boitnott, Richard L.; Reaves, Mercedes; Mark, Stephen D.; Annett, Martin S.

2011-01-01

252

Simulation Framework for Rapid Entry, Descent, and Landing (EDL) Analysis, Phase 2 Results  

NASA Technical Reports Server (NTRS)

The NASA Engineering and Safety Center (NESC) was requested to establish the Simulation Framework for Rapid Entry, Descent, and Landing (EDL) Analysis assessment, which involved development of an enhanced simulation architecture using the Program to Optimize Simulated Trajectories II simulation tool. The assessment was requested to enhance the capability of the Agency to provide rapid evaluation of EDL characteristics in systems analysis studies, preliminary design, mission development and execution, and time-critical assessments. Many of the new simulation framework capabilities were developed to support the Agency EDL-Systems Analysis (SA) team that is conducting studies of the technologies and architectures that are required to enable human and higher mass robotic missions to Mars. The findings, observations, and recommendations from the NESC are provided in this report.

Murri, Daniel G.

2011-01-01

253

Integrated land-use systems: Assessment of promising agroforest and alternative land-use practices to enhance carbon conservation and sequestration  

Microsoft Academic Search

Degraded or sub-standard soils and marginal lands occupy a significant proportion of boreal, temperate and tropical biomes. Management of these lands with a wide range of existing, site-specific, integrated, agroforest systems represents a significant global opportunity to reduce the accumulation of greenhouse gases in the atmosphere. Establishment of extensive agricultural, agroforest, and alternative land-use systems on marginal or degraded lands

Robert K. Dixon; Jack K. Winjum; Kenneth J. Andrasko; Jeffrey J. Lee; Paul E. Schroeder

1994-01-01

254

Application of scenario analysis and multiagent technique in land-use planning: a case study on Sanjiang wetlands.  

PubMed

Land-use planning has triggered debates on social and environmental values, in which two key questions will be faced: one is how to see different planning simulation results instantaneously and apply the results back to interactively assist planning work; the other is how to ensure that the planning simulation result is scientific and accurate. To answer these questions, the objective of this paper is to analyze whether and how a bridge can be built between qualitative and quantitative approaches for land-use planning work and to find out a way to overcome the gap that exists between the ability to construct computer simulation models to aid integrated land-use plan making and the demand for them by planning professionals. The study presented a theoretical framework of land-use planning based on scenario analysis (SA) method and multiagent system (MAS) simulation integration and selected freshwater wetlands in the Sanjiang Plain of China as a case study area. Study results showed that MAS simulation technique emphasizing quantitative process effectively compensated for the SA method emphasizing qualitative process, which realized the organic combination of qualitative and quantitative land-use planning work, and then provided a new idea and method for the land-use planning and sustainable managements of land resources. PMID:23818816

Yu, Huan; Ni, Shi-Jun; Kong, Bo; He, Zheng-Wei; Zhang, Cheng-Jiang; Zhang, Shu-Qing; Pan, Xin; Xia, Chao-Xu; Li, Xuan-Qiong

2013-01-01

255

Land cover analysis of James City County, Virginia  

NASA Technical Reports Server (NTRS)

The approach used to obtain reliable countywide forest resource data, including statistics and a forest cover distribution map from LANDSAT data is described. Comparison of results of the LANDSAT anlysis and U.S. Forestry Survey data is presented in a table. Pine, oak/pine, and oak/hickory accounted for 22.3%, 32.6% and 45.2% respectively of the total forest area in the LANDSAT analysis, compared to 22.8%, 30.1%. and 47.1% in the Forest Survey. The corresponding figures for each forest type differ at most 2.5% for the mixed forest. The total county area in forest land measured using LANDSAT was underestimated by 1,409 acres, a 2.2% error based on the Forest Survey statistics. However, the estimate of 61,242 acres fell well within the known 4% uncertainty of the estimate for the Forest Survey figures (62,651 acres + or - 2,544 acres).

Copony, J. A.; Middleton, E. M.; Bly, B. G.

1981-01-01

256

Drivers of land use change and household determinants of sustainability in smallholder farming systems of Eastern Uganda  

PubMed Central

Smallholder farming systems in sub-Saharan Africa have undergone changes in land use, productivity and sustainability. Understanding of the drivers that have led to changes in land use in these systems and factors that influence the systems’ sustainability is useful to guide appropriate targeting of intervention strategies for improvement. We studied low input Teso farming systems in eastern Uganda from 1960 to 2001 in a place-based analysis combined with a comparative analysis of similar low input systems in southern Mali. This study showed that policy-institutional factors next to population growth have driven land use changes in the Teso systems, and that nutrient balances of farm households are useful indicators to identify their sustainability. During the period of analysis, the fraction of land under cultivation increased from 46 to 78%, and communal grazing lands nearly completely disappeared. Cropping diversified over time; cassava overtook cotton and millet in importance, and rice emerged as an alternative cash crop. Impacts of political instability, such as the collapse of cotton marketing and land management institutions, of communal labour arrangements and aggravation of cattle rustling were linked to the changes. Crop productivity in the farming systems is poor and nutrient balances differed between farm types. Balances of N, P and K were all positive for larger farms (LF) that had more cattle and derived a larger proportion of their income from off-farm activities, whereas on the medium farms (MF), small farms with cattle (SF1) and without cattle (SF2) balances were mostly negative. Sustainability of the farming system is driven by livestock, crop production, labour and access to off-farm income. Building private public partnerships around market-oriented crops can be an entry point for encouraging investment in use of external nutrient inputs to boost productivity in such African farming systems. However, intervention strategies should recognise the diversity and heterogeneity between farms to ensure efficient use of these external inputs. PMID:20628448

de Ridder, Nico; de Jager, Andre; Delve, Robert J.; Bekunda, Mateete A.; Giller, Ken E.

2010-01-01

257

Activities of the Pilot Land Data System project  

NASA Technical Reports Server (NTRS)

The University of Maryland's Remote Sensing Systems Laboratory submitted to NASA/Goddard an interim progress report on the work being conducted within its Pilot Land Data System IPLDS project. The Remote Sensing Systems Laboratory addressed the following tasks: (1) identify data types and data sources needed to describe the selected test sites in collaboration with Goddard's Hydrological Sciences Branch; (2) define the procedures necessary to access/acquire this data; (3) conduct meetings with the PLDS Systems Engineering Group to identify functional specification priorities for PLDS development; (4) assemble documentation on historical remotely sensed imagery and transfer of such information to the PLDS Data Management Group; (5) collect data identified by Goodard's Hydrological Sciences Branch for data set inventory in PLD; (6) develop a Workstation-PLDS system interface over high speed lines, (7) develop and test through a Phase 1 demonstration of a micro workstation to access PLDS; and (8) establish interdepartmental agreement of development of computer link for electronic access of water resources data from USGS.

Sircar, J. K. (principal investigator)

1985-01-01

258

Land use and land cover classification, changes and analysis in gum Arabic belt in North Kordofan, Sudan  

NASA Astrophysics Data System (ADS)

The gum arabic belt in Sudan plays a significant role in environmental, social and economical aspects. This research was conducted in North Kordofan State, which is affected by modifications in conditions and composition of vegetation cover trends in the gum arabic belt as in the rest of the Sahelian Sudan zone. The objective of the paper is to study the classification, changes and analysis of the land use and land cover in the gum arabic belt in North Kordofan State in Sudan. The study used imageries from different satellites (Landsat and ASTER) and multi-temporal dates (MSS 1972, TM 1985, ETM+ 1999 and ASTER 2007) acquired in dry season. The imageries were geo-referenced and radiometrically corrected by using ENVI-FLAASH software. Image classification (pixel-based) and accuracy assessment were applied. Application of multi-temporal remote sensing data demonstrated successfully the identification and mapping of land use and land cover into five main classes. Forest dominated by Acacia senegal class was separated covering an area of 21% in the year 2007. The obvious changes and reciprocal conversions in the land use and land cover structure indicate the trends and conditions caused by the human interventions as well as ecological impacts on Acacia senegal trees. Also the study revealed that a drastic loss of forest resources occurred in the gum arabic belt in North Kordofan during 1972 to 2007 (25% for Acacia senegal trees). The study concluded that, using of traditional Acacia senegal-based agro-forestry as one of the most successful form in the gum belt.

Adam, Hassan E.; Csaplovics, Elmar; Elhaja, Mohamed E.; El Abbas, Mustafa M.

2013-10-01

259

Elimination of background clutter in airports for instrument landing systems  

NASA Astrophysics Data System (ADS)

Specular reflection from airport buildings interferes with instrument landing systems. It is possible to eliminate these specular reflections by periodic strip grating techniques. These metallic strips, when painted over a dielectric sheet, are found to eliminate the specular reflections from a plane metallic surface and the surface behaves as a `non reflecting conducting surface.' These inexpensive surfaces are lightweight and have the added advantage of ease in fabrication. It is easy to apply metallic paint in a regularly spaced strip pattern. By a suitable choice of the period `d' and the thickness of the dielectric medium (the wall), it is possible to eliminate reflections at any desired angle. It may also be possible to eliminate the reflections from other targets like cylinders and corner reflectors.

Jose, K. A.; Varadan, Vijay K.; Varadan, Vasundara V.

1994-05-01

260

23 CFR 970.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2010 CFR

...HIGHWAYS NATIONAL PARK SERVICE MANAGEMENT SYSTEMS National Park Service Management Systems § 970.210 Federal lands bridge management system (BMS). In addition... (2) A system for applying network level analytical...

2010-04-01

261

23 CFR 971.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2010 CFR

... Federal lands bridge management system (BMS). In...Guidelines for Bridge Management Systems.” 2 2 “Guidelines for Bridge Management Systems,” AASHTO...A system for applying network level analytical...

2010-04-01

262

Assessing sustainable land-use practices using geographic information systems  

NASA Astrophysics Data System (ADS)

Many prominent scientists have claimed that we need to develop environmentally sustainable practices otherwise societies may collapse. The use of Geographic Information Systems allows detailed studies that can cross disciplinary boundaries and lead to quantifiable statements as to the change of land use practices that took place in the past and those that may occur in the future. This dissertation focuses on two research topics. One that attempts to quantify the environmental consequences of parking lots located in the Midwest, USA. The other research topic focuses on the land area needed to support ethanol in the United States. In Tippecanoe County, Indiana, it was determined that parking lots occupied approximately 6.6% of the urban areas, that the area devoted to parking lots exceeded the area devoted to urban parks by a factor of 3, and that these parking lots contributed to increased runoff of pollutants. The parking lots of Tippecanoe County were estimated to be responsible for 46.5 thousand pounds of oil and grease released annually in runoff, as well as an increase of 240.6 thousand pounds of suspended solids, and 65.7 pounds of lead released when compared to pre-development conditions. A method that scales up the county wide study was also developed to determine the areal footprint of parking lots with the states of Illinois, Indiana, Michigan and Wisconsin. It was estimated that these four states allocate approximately 1260 square km of their land to parking lots and that this accounts for 4.97% of urban land use and over 43 million parking spaces, whereas the number of individuals in age of driving (adults over 18 years old) amounted to just over 25 million. Within the four states studied, states where urban sprawl was considered more prevalent were also states that had a higher proportion of their urban land devoted to parking lots. The second dissertation topic focused on using GIS to locate suitable sites for corn or cellulosic based ethanol production facilities. Since a valuable byproduct of corn ethanol production is Distiller's Grain Solubles (DGS), siting of ethanol plants was considered with regard to both corn production by county within the conterminous United States and head of cattle available to use this output as feed. We found that many counties outside the Midwest could sustain smaller sized ethanol plants, especially when considering that most large production facilities need to redistribute their DGS in dried form sometimes as far as California which has negative impacts on the Net Energy Value of corn based ethanol. The future of ethanol expansion however lies with cellulosic feedstock which is bulkier and thus more costly to transport than corn. Our results indicate that cellulosic ethanol plants should be smaller in capacity, especially when compared to corn ethanol plants where 100 million gallons a year (mgy) plants are more the norm. Only 7 out of 3109 counties in the conterminous United States contain enough wood, switchgrass or crop residue feedstock to sustain plants that produce greater than 40 mgy of biofuel, meaning that larger plants would need to import feedstock from considerable distances and thus incur greater feedstock transport costs. The last section explored co-location options for siting lignocellulosic ethanol plant production facilities.

Davis, Amelie Y.

263

Detection of land use/land cover changes through the comparative analysis of NDVI-MODIS phenological clusters  

NASA Astrophysics Data System (ADS)

The use of satellite time series provides precious information to understand vegetation dynamics. In particular, they can be profitably used for studying magnitudo and spatial extent of the Earth's land cover alterations, which affect directly biodiversity, can contribute to land degradation, and are linked to climate change by feedback mechanisms. In the framework of PRO-LAND project (PO-FESR Basilicata 2007-2013), we used NDVI-MODIS satellite time series (250 m), available as 16-day composite from the NASA LPDAAC dataset, to analyze land cover changes occurred in Basilicata region (Southern Italy) during the period 2000-2010. We performed a phenological clustering for the years 2000 and 2010 by means of the unsupervised classification fuzzy k-means which is able to identify gradual differences among phenological patterns. The time domain considered is from April to October in order to reduce disturbances due to the presence of clouds, which can distort actual vegetation phenological profiles. The optimal number of clusters to capture the heterogeneity of the examined area was fixed at ten, because it seemed to be a good trade-off between the need of an efficient representation of ecosystems and the ability to detect local fragmentation effects. Results show that the temporal patterns of the ten clusters can be organised in a continuum of phenological curves. They can be sorted unambiguously according to increasing percentage of man-made areas (decreasing percentage of natural areas) and allow us to well discriminate different land cover compositions by looking not only at differences in mean NDVI values but also at differences in the seasonal timing. The cluster sequence for both the examined years mostly follows the spatial arrangement of the land cover classes, and the complex orography of the investigated region. In general, results show that a slight variability characterize the arrangement of cluster cores, particularly for the clusters with a dominance of natural or anthropic covers, whereas a slightly higher variability appears at the cluster borders (especially for clusters where anthropic and natural covers are mixed). Overall, this study puts into evidence a fair decrease in the number of patches (~ -10%) accompanied by the increase of the mean patch area (~ +10%), which means that there is a tendency to compaction of the areas that are classified in the same phenological cluster. This phenomenon is particularly interesting for mountainous natural areas. A coupled analysis of meteo-climatic conditions and implemented land cover management policies can enable to identify the causes behind the observed phenomena, allowing for a more complete picture and a better interpretation of the occurred land cover changes.

Simoniello, Tiziana; Imbrenda, Vito; Lanfredi, Maria

2013-04-01

264

Green Infrastructure & Sustainable Urban Land Use Decision Analysis Workshop  

EPA Science Inventory

Introduce green infrastructure, concepts and land use alternatives, to City of Cleveland operations staff. Discuss potential of green alternatives to impact daily operations and routine maintenance activities. Tie in sustainability concepts to long-term City planning and discu...

265

23 CFR 971.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2010 CFR

... Federal lands pavement management system (PMS). In addition...the AASHTO's “Pavement Management Guide.” 1 1 “Pavement Management Guide,” AASHTO...nature of the transportation network. These different...

2010-04-01

266

78 FR 58555 - Public Land Order No. 7821; Withdrawal of National Forest System Land for Steamboat Rock Picnic...  

Federal Register 2010, 2011, 2012, 2013

...National Forest System Land for Steamboat Rock Picnic Grounds; South Dakota AGENCY...uses and improvements at the Steamboat Rock Picnic Grounds within the Black Hills National...uses and improvements within the Steamboat Rock Picnic Grounds. Order By virtue of...

2013-09-24

267

Detecting land-use/land-cover change in rural-urban fringe areas using extended change-vector analysis  

NASA Astrophysics Data System (ADS)

Detecting land-use/land-cover (LULC) changes in rural-urban fringe areas (RUFAs) timely and accurately using satellite imagery is essential for land-use planning and management in China. Although traditional spectral-based change-vector analysis (CVA) can effectively detect LULC change in many cases, it encounters difficulties in RUFAs because of deficiencies in the spectral information of satellite images. To detect LULC changes in RUFAs effectively, this paper proposes an extended CVA approach that incorporates textural change information into the traditional spectral-based CVA. The extended CVA was applied to three different pilot RUFAs in China with different remotely sensed data, including Landsat Thematic Mapper (TM), China-Brazil Earth Resources Satellite (CBERS) and Advanced Land Observing Satellite (ALOS) images. The results demonstrated the improvement of the extended CVA compared to the traditional spectral-based CVA with the overall accuracy increased between 4.66% and 8.00% and the kappa coefficient increased between 0.10 and 0.15, respectively. The advantage of the extended CVA lies in its integration of both spectral and textural change information to detect LULC changes, allowing for effective discrimination of LULC changes that are spectrally similar but texturally different in RUFAs. The extended CVA has great potential to be widely used for LULC-change detection in RUFAs, which are often heterogeneous and fragmental in nature, with rich textural information.

He, Chunyang; Wei, Anni; Shi, Peijun; Zhang, Qiaofeng; Zhao, Yuanyuan

2011-08-01

268

A Land-Use Modelling System for Environmental Impact Assessment  

Microsoft Academic Search

Changes in land use may have important implications for nature, environment and water management. Thus, insights into future\\u000a land-use patterns are needed for explorations of the future state of the environment and subsequent policy making. The Netherlands\\u000a Environmental Assessment Agency, in co-operation with other partners, funded a consortium with the aim to invest in further\\u000a development of the Land Use

J. Borsboom-van Beurden; A. Bakema; H. Tijbosch

269

23 CFR 971.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Federal lands bridge management system (BMS). 971.210...Systems § 971.210 Federal lands bridge management system (BMS). In addition...partnership shall have a BMS for the FH bridges funded under the FLHP and required...

2013-04-01

270

23 CFR 970.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Federal lands bridge management system (BMS). 970.210...Systems § 970.210 Federal lands bridge management system (BMS). In addition...a) The NPS shall have a BMS for the bridges which are under the NPS...

2012-04-01

271

23 CFR 970.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Federal lands bridge management system (BMS). 970.210...Systems § 970.210 Federal lands bridge management system (BMS). In addition...a) The NPS shall have a BMS for the bridges which are under the NPS...

2011-04-01

272

23 CFR 970.210 - Federal lands bridge management system (BMS).  

...2014-04-01 false Federal lands bridge management system (BMS). 970.210...Systems § 970.210 Federal lands bridge management system (BMS). In addition...a) The NPS shall have a BMS for the bridges which are under the NPS...

2014-04-01

273

23 CFR 970.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Federal lands bridge management system (BMS). 970.210...Systems § 970.210 Federal lands bridge management system (BMS). In addition...a) The NPS shall have a BMS for the bridges which are under the NPS...

2013-04-01

274

23 CFR 973.210 - Indian lands bridge management system (BMS).  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Indian lands bridge management system (BMS). 973.210...Management Systems § 973.210 Indian lands bridge management system (BMS). In addition...for the federally and tribally owned IRR bridges that are funded under the FLHP and...

2011-04-01

275

23 CFR 971.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Federal lands bridge management system (BMS). 971.210...Systems § 971.210 Federal lands bridge management system (BMS). In addition...partnership shall have a BMS for the FH bridges funded under the FLHP and required...

2012-04-01

276

23 CFR 973.210 - Indian lands bridge management system (BMS).  

... 2014-04-01 false Indian lands bridge management system (BMS). 973.210...Management Systems § 973.210 Indian lands bridge management system (BMS). In addition...for the federally and tribally owned IRR bridges that are funded under the FLHP and...

2014-04-01

277

23 CFR 971.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Federal lands bridge management system (BMS). 971.210...Systems § 971.210 Federal lands bridge management system (BMS). In addition...partnership shall have a BMS for the FH bridges funded under the FLHP and required...

2011-04-01

278

23 CFR 971.210 - Federal lands bridge management system (BMS).  

...2014-04-01 false Federal lands bridge management system (BMS). 971.210...Systems § 971.210 Federal lands bridge management system (BMS). In addition...partnership shall have a BMS for the FH bridges funded under the FLHP and required...

2014-04-01

279

23 CFR 973.210 - Indian lands bridge management system (BMS).  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 false Indian lands bridge management system (BMS). 973.210...Management Systems § 973.210 Indian lands bridge management system (BMS). In addition...for the federally and tribally owned IRR bridges that are funded under the FLHP and...

2012-04-01

280

23 CFR 973.210 - Indian lands bridge management system (BMS).  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Indian lands bridge management system (BMS). 973.210...Management Systems § 973.210 Indian lands bridge management system (BMS). In addition...for the federally and tribally owned IRR bridges that are funded under the FLHP and...

2013-04-01

281

Land Application of Wastes: An Educational Program. Costing Land Application Systems - Module 10.  

ERIC Educational Resources Information Center

This module expands on the concepts of cost estimation and comparison of costs among various treatment alternatives which were presented in a previous module. The need for useful published cost data is stressed. Criteria for selecting cost references are presented, and examples of charts and graphs from several of these are used in comparing land

Clarkson, W. W.; And Others

282

A prototype Global Drought Information System based on multiple land surface models  

NASA Astrophysics Data System (ADS)

Droughts are pervasive natural hazards, which cause large economic losses and human suffering. While the absolute magnitude of these losses is greatest in the developed world, the relative impact is much higher in the developing world. Nonetheless, our ability to monitor and predict the development and occurrence of droughts at a global scale in near real-time is limited. This ability is of particular importance in estimating regional crop production and thus current and future prices of agricultural commodities, as well as the implementation of emergency measures in areas where the effects of drought threaten lives and livelihoods. We describe the implementation of a multi-model drought monitoring system, which provides near real-time estimates of soil moisture conditions for the global land areas between 50S and 50N with a latency of about one day. The system is an extension of similar systems developed by both the University of Washington and the National Centers for Environmental Prediction for use in the U.S. Drought Monitor. Global application of the protocols used in the U.S. systems poses new challenges, particularly with respect to the generation of meteorological forcings with which to drive the land surface models used in such a system. The global system we describe uses satellite-based precipitation (as contrasted with gridded station data in the U.S. systems) as well as temperature estimates based on global weather model analysis fields to track the evolution of soil moisture in near real-time at a spatial resolution of 0.5 degree using multiple land surface models. By comparing the modeled, near real-time soil moisture values with the results from long-term retrospective simulations, the model estimates can be placed in historic context (as soil moisture percentiles) and used to monitor the development of droughts around the world. We evaluate the performance of our system for historic droughts, and compare with other drought analyses and analytical data.

Nijssen, Bart; Shukla, Shrad; Lin, Chi-Yu; Lettenmaier, Dennis

2013-04-01

283

Analysis on the spatio-temporal changes of sustainable land use in Tibet  

Microsoft Academic Search

By constructing evaluation indicator system of sustainable land use of Tibet from three aspects of ecological environment,\\u000a economic development, resources and social advancement, this article studies the following contents respectively in two dimensions\\u000a of time and space: the changes of sustainable land use of Tibet in recent 20 years and spatial characteristics of sustainable\\u000a land use of Tibet in 2002.

Gu Shixian; Xu Xia; Liu Shuzhen

2006-01-01

284

Runway landing safety analysis: a case study of Atlanta Hartsfield airport  

Microsoft Academic Search

According to historical data, aircraft are subject to a higher accident risk during the landing phase than during other flight phases. With the growth in air traffic volume evaluating safety during the landing phase is an important problem. This paper presents an analysis and estimate of two safety metrics at ATL airport: probability of a simultaneous runway occupancy by two

Yue Xie; John Shortle; George Donohue

2003-01-01

285

Scale and accessibility: Implications for the analysis of land use–travel interaction  

Microsoft Academic Search

An important methodological issue in accessibility research is how the results are affected by geographical scale. Understanding the scale effect and the associated modifiable areal unit problem (MAUP) is also important for the analysis of land use–travel interaction. Using a distinct type of accessibility measures, namely space–time measures, this study examines whether the relationships among accessibility, land use, and personal

Mei-Po Kwan; Joe Weber

2008-01-01

286

Soil Moisture Memory in AGCM Simulations: Analysis of Global LandAtmosphere Coupling Experiment (GLACE) Data  

E-print Network

Soil Moisture Memory in AGCM Simulations: Analysis of Global Land­Atmosphere Coupling Experiment 2006) ABSTRACT Soil moisture memory is a key aspect of land­atmosphere interaction and has major implications for seasonal forecasting. Because of a severe lack of soil moisture observations on most

Haak, Hein

287

Restriction Analysis of Residual Capacity of Intersection on Land Development Intensity  

Microsoft Academic Search

At present, the common existing problem of Traffic Impact Analysis (TIA) is that there is no control on land development intensity on the stage of approval. This paper evaluates the restriction of residual capacity of intersection on land development intensity. Intersection is frequently a bottleneck of urban road network. With estimation of the proportion of turning flow and consideration of

Zhiqiang LIU; Jie CHEN; Jie NI; Li ZHANG

2011-01-01

288

On the Impact of Future Land Use Assumptions on Risk Analysis for Superfund Sites  

Microsoft Academic Search

In this paper, assumptions regarding future land use as a key uncertainty is considered and its impact on risk analysis for contaminated sites is assessed. Risks are assessed for two land use scenarios (current-use industrial and future-use residential) using probabilistic models that incorporate uncertainty and variability in the exposure parameters. Residual risks are calculated for both industrial and residential cleanup

Peter T. Katsumata; William E. Kastenberg

1997-01-01

289

Concrete evidence & geographically weighted regression: A regional analysis of wealth and the land cover in Massachusetts  

Microsoft Academic Search

Several studies indicate that there is a positive relationship between green vegetation land cover and wealthy socio-economic conditions in urban areas. The purpose of this research is to test for and explore spatial variation in the relationship between socio-economic and green vegetation land cover across urban, suburban, and rural areas, using geographically weighted regression (GWR). The analysis was conducted at

Yelena Ogneva-Himmelberger; Hamil Pearsall; Rahul Rakshit

2009-01-01

290

Manifesting Destiny: A Land Education Analysis of Settler Colonialism in Jamestown, Virginia, USA  

ERIC Educational Resources Information Center

Globally, colonization has been and continues to be enacted in the take-over of Indigenous land and the subsequent conversion of agriculture from diverse food and useful crops to large-scale monoculture and cash crops. This article uses a land education analysis to map the rise of the ideology and practices of Manifest Destiny in Virginia.…

McCoy, Kate

2014-01-01

291

Landing and Population Hazard Analysis for Stardust Entry in Operations and Entry Planning  

NASA Technical Reports Server (NTRS)

Stardust is a comet sample return mission that successfully returned to Earth on January 15, 2006. Stardust's targeted landing area was the Utah Test and Training Range in the Northwest corner of Utah. Requirements for the risks associated with landing were levied on Stardust by the Utah Test and Training Range and NASA. This paper describes the analysis to verify that these requirements were met and and includes calculation of debris survivability, generation of landing site selection plots, and identification of keep-out zones, as well as appropriate selection of the landing site. Operationally the risk requirements were all met for both of the GOMO-GO polls, so entry was authorized.

Tooley, Jeffrey; Desai, Prasun N.; Lynos, Daniel T.; Hirst, Edward A.; Wahl, Tom E.; Wawrzyniak, Georffery G.

2006-01-01

292

Estimating impacts of land use on groundwater quality using trilinear analysis.  

PubMed

Groundwater is connected to the landscape above and is thus affected by the overlaying land uses. This study evaluated the impacts of land uses upon groundwater quality using trilinear analysis. Trilinear analysis is a display of experimental data in a triangular graph. Groundwater quality data collected from agricultural, septic tank, forest, and wastewater land uses for a 6-year period were used for the analysis. Results showed that among the three nitrogen species (i.e., nitrate and nitrite (NO(x)), dissolved organic nitrogen (DON), and total organic nitrogen (TON)), NO(x) had a high percentage and was a dominant species in the groundwater beneath the septic tank lands, whereas TON was a major species in groundwater beneath the forest lands. Among the three phosphorus species, namely the particulate phosphorus (PP), dissolved ortho phosphorus (PO4(3-)) and dissolved organic phosphorus (DOP), there was a high percentage of PP in the groundwater beneath the septic tank, forest, and agricultural lands. In general, Ca was a dominant cation in the groundwater beneath the septic tank lands, whereas Na was a dominant cation in the groundwater beneath the forest lands. For the three major anions (i.e., F(-), Cl(-), and SO4(2-)), F(-) accounted for <1% of the total anions in the groundwater beneath the forest, wastewater, and agricultural lands. Impacts of land uses on groundwater Cd and Cr distributions were not profound. This study suggests that trilinear analysis is a useful technique to characterize the relationship between land use and groundwater quality. PMID:24802588

Ouyang, Ying; Zhang, Jia En; Cui, Lihua

2014-09-01

293

An automated land-use mapping comparison of the Bayesian maximum likelihood and linear discriminant analysis algorithms  

NASA Technical Reports Server (NTRS)

The Bayesian maximum likelihood parametric classifier has been tested against the data-based formulation designated 'linear discrimination analysis', using the 'GLIKE' decision and "CLASSIFY' classification algorithms in the Landsat Mapping System. Identical supervised training sets, USGS land use/land cover classes, and various combinations of Landsat image and ancilliary geodata variables, were used to compare the algorithms' thematic mapping accuracy on a single-date summer subscene, with a cellularized USGS land use map of the same time frame furnishing the ground truth reference. CLASSIFY, which accepts a priori class probabilities, is found to be more accurate than GLIKE, which assumes equal class occurrences, for all three mapping variable sets and both levels of detail. These results may be generalized to direct accuracy, time, cost, and flexibility advantages of linear discriminant analysis over Bayesian methods.

Tom, C. H.; Miller, L. D.

1984-01-01

294

Land Cover and Landscape Diversity Analysis in the West Polesie Biosphere Reserve  

NASA Astrophysics Data System (ADS)

The aim of this research was to present the land cover structure and landscape diversity in the West Polesie Biosphere Reserve. The land cover classification was performed using Object Based Image Analysis in Trimble eCognition Developer 8 software. The retrospective land cover changes analysis in 3 lake catchments (Kleszczów, Moszne, Bia³eW³odawskie Lakes)was performed on the basis of archival aerial photos taken in 1952, 1971, 1984, 1992, 2007 and one satellite scene from 2003 (IKONOS).On the basis of land cover map structure, Shannon diversity index was estimated with the moving window approach enabled in Fragstats software. The conducted research has shown that the land cover structure of the West Polesie Biosphere Reserve is diverse and can be simply described by selected landscape metrics. The highest level of land cover diversity, as showed by Shannon Diversity Index, was identified in the western part of the West Polesie Biosphere Reserve, which is closely related to the agricultural character of land cover structure in those regions. The examples of three regional retrospective land cover analyses demonstrated that the character of land cover structure has changed dramatically over the last 40 years.

Chmielewski, Szymon; Chmielewski, Tadeusz J.; Tompalski, Piotr

2014-04-01

295

Analysis of Renewable Energy Potential on U. S. National Forest Lands  

SciTech Connect

In 2005, the National Renewable Energy Laboratory (NREL) completed an assessment of the potential for solar and wind energy development on National Forest System (NFS) public lands managed by the US Department of Agriculture, U.S. Forest Service (USFS). This report provides an update of the analysis in the NREL report, and extends the analysis with additional siting factors for solar and wind energy. It also expands the scope to biomass and geothermal energy resources. Hydropower is acknowledged as another major renewable energy source on NFS lands; however, it was not analyzed in this project primarily because of the substantially different analysis that would be needed to identify suitable locations. Details about each renewable energy production technology included in the study are provided following the report introduction, including how each resource is converted to electrical power, and examples of existing power plants. The analysis approach was to use current and available Geographic Information System (GIS) data to map the distribution of the subject renewable energy resources, major siting factors, and NFS lands. For each major category of renewable energy power production, a set of siting factors were determined, including minimum levels for the renewable energy resources, and details for each of the other siting factors. Phase 1 of the analysis focused on replicating and updating the 2005 NREL analysis, and Phase 2 introduced additional siting factors and energy resources. Source data were converted to a cell?based format that helped create composite maps of locations meeting all the siting criteria. Acreages and potential power production levels for NFS units were tabulated and are presented throughout this report and the accompanying files. NFS units in the southwest United States were found to have the most potentially suitable land for concentrating solar power (CSP), especially in Arizona and New Mexico. In total, about 136,032 acres of NFS lands were found potentially suitable for CSP development, potentially yielding as much as 13,603 megawatts (MW) of electricity, assuming 10 acres per MW. For photovoltaic solar power (PV), the top NFS units were more widely distributed than CSP. Notably, more than 150,000 acres in Comanche National Grassland in Colorado were found to be potentially suitable for PV development, accounting for more than 25% of the potentially suitable NFS lands combined. In total, about 564,698 acres of NFS lands were found potentially suitable for PV development, potentially yielding as much as 56,469 MW of electricity, assuming 10 acres per MW. NFS units most suitable for wind power are concentrated in the northern Great Plains. In total, about 3,357,792 acres of NFS lands were found potentially suitable for wind development, potentially yielding as much as 67,156 MW of electricity, assuming 50 acres per MW. Of that area, 571,431 acres (11,429 MW) are located within the Bankhead?Jones Farm Tenant Act Land in Montana. NFS lands in Alaska have considerable wind resources, but other siting factors eliminated almost the entire area. The southwest coast of Chugach National Forest, near Seward, Alaska, maintains the majority of the remaining acreage. NFS units with highly suitable biomass resources are located from Idaho to Louisiana. In total, about 13,967,077 acres of NFS lands are potentially highly suitable for biomass from logging and thinning residue development. Of that, 1,542,247 acres is located in Fremont?Winema National Forest in Oregon. Not surprisingly, most NFS units have at least some level of potentially suitable biomass resources. In general, biomass resources such as these could significantly offset consumption of coal and petroleum?based fuels. NFS units deemed potentially highly suitable for enhanced geothermal system (EGS) development were distributed widely from California to Virginia, accounting for some 6,475,459 acres. Mark Twain National Forest in Missouri has the largest area of all the NFS units, with 900,637 acres. While more rigorous studies are needed

Zvolanek, E. [Environmental Science Division] [Environmental Science Division; Kuiper, J. [Environmental Science Division] [Environmental Science Division; Carr, A. [Environmental Science Division] [Environmental Science Division; Hlava, K.

2013-12-13

296

23 CFR 971.214 - Federal lands congestion management system (CMS).  

Code of Federal Regulations, 2010 CFR

...HIGHWAYS FOREST SERVICE MANAGEMENT SYSTEMS Forest Highway Program Management Systems § 971.214 Federal lands congestion management system (CMS). ...interference. For portions of the FH network outside the boundaries...

2010-04-01

297

23 CFR 972.210 - Federal lands bridge management system (BMS).  

Code of Federal Regulations, 2010 CFR

...AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems § 972.210 Federal lands bridge management system (BMS). In addition to...shall be designed to fit the FWS goals, policies, criteria,...

2010-04-01

298

Experimental and analytical studies of advanced air cushion landing systems  

NASA Technical Reports Server (NTRS)

Several concepts are developed for air cushion landing systems (ACLS) which have the potential for improving performance characteristics (roll stiffness, heave damping, and trunk flutter), and reducing fabrication cost and complexity. After an initial screening, the following five concepts were evaluated in detail: damped trunk, filled trunk, compartmented trunk, segmented trunk, and roll feedback control. The evaluation was based on tests performed on scale models. An ACLS dynamic simulation developed earlier is updated so that it can be used to predict the performance of full-scale ACLS incorporating these refinements. The simulation was validated through scale-model tests. A full-scale ACLS based on the segmented trunk concept was fabricated and installed on the NASA ACLS test vehicle, where it is used to support advanced system development. A geometrically-scaled model (one third full scale) of the NASA test vehicle was fabricated and tested. This model, evaluated by means of a series of static and dynamic tests, is used to investigate scaling relationships between reduced and full-scale models. The analytical model developed earlier is applied to simulate both the one third scale and the full scale response.

Lee, E. G. S.; Boghani, A. B.; Captain, K. M.; Rutishauser, H. J.; Farley, H. L.; Fish, R. B.; Jeffcoat, R. L.

1981-01-01

299

Definition and testing of the hydrologic component of the pilot land data system  

NASA Technical Reports Server (NTRS)

The specific aim was to develop within the Pilot Land Data System (PLDS) software design environment, an easily implementable and user friendly geometric correction procedure to readily enable the georeferencing of imagery data from the Advanced Very High Resolution Radiometer (AVHRR) onboard the NOAA series spacecraft. A software subsystem was developed within the guidelines set by the PLDS development environment utilizing NASA Goddard Space Flight Center (GSFC) Image Analysis Facility's (IAF's) Land Analysis Software (LAS) coding standards. The IAS current program development environment, the Transportable Applications Executive (TAE), operates under a VAX VMS operating system and was used as the user interface. A brief overview of the ICARUS algorithm that was implemented in the set of functions developed, is provided. The functional specifications decription is provided, and a list of the individual programs and directory names containing the source and executables installed in the IAF system are listed. A user guide is provided for the LAS system documentation format for the three functions developed.

Ragan, Robert M.; Sircar, Jayanta K.

1987-01-01

300

Flight test evaluation of the Stanford University/United Airlines differential GPS Category 3 automatic landing system  

NASA Technical Reports Server (NTRS)

Test flights were conducted to evaluate the capability of Differential Global Positioning System (DGPS) to provide the accuracy and integrity required for International Civil Aviation Organization (ICAO) Category (CAT) 3 precision approach and landings. These test flights were part of a Federal Aviation Administration (FAA) program to evaluate the technical feasibility of using DGPS based technology for CAT 3 precision approach and landing applications. A United Airlines Boeing 737-300 (N304UA) was equipped with DGPS receiving equipment and additional computing capability provided by Stanford University. The test flights were conducted at NASA Ames Research Center's Crows Landing Flight Facility, Crows Landing, California. The flight test evaluation was based on completing 100 approaches and autolandings; 90 touch and go, and 10 terminating with a full stop. Two types of accuracy requirements were evaluated: 1) Total system error, based on the Required Navigation Performance (RNP), and 2) Navigation sensor error, based on ICAO requirements for the Microwave Landing System (MLS). All of the approaches and autolandings were evaluated against ground truth reference data provided by a laser tracker. Analysis of these approaches and autolandings shows that the Stanford University/United Airlines system met the requirements for a successful approach and autolanding 98 out of 100 approaches and autolandings, based on the total system error requirements as specified in the FAA CAT 3 Level 2 Flight Test Plan.

Kaufmann, David N.; Ncnally, B. David

1995-01-01

301

Landing Characteristics of the Apollo Spacecraft with Deployed Heat Shield Impact Attenuation System  

NASA Technical Reports Server (NTRS)

Landing Characteristics of the Apollo Spacecraft with Deployed Heat Shield Impact Attenuation Systems. An experimental investigation was made to determine the landing characteristics of a 1/4-scale dynamic model of the Apollo spacecraft command module using two different active (heat shield deployed prior to landing) landing systems for impact attenuation. One landing system (configuration 1) consisted of six hydraulic struts and eight crushable honeycomb struts. The other landing system (configuration 2), consisted of four hydraulic struts and six strain straps. Tests made on water and the hard clay-gravel composite landing surfaces simulated parachute letdown (vertical) velocities of 23 ft/sec (7.0 m/s) (full scale). Landings made on the sand landing surface simulated vertical velocities of 30 ft/sec (9.1 m/s). Horizontal velocities of from 0 to 50 ft/sec (15 m/s) were simulated. Landing attitudes ranged from -30'degrees to 20 degrees, and the roll attitudes were O degrees, 90 degrees, and 180 degrees. For configuration 1, maximum normal accelerations at the vehicle center of gravity for landings on water, sand, and the hard clay-gravel composite surface were 9g, 20g, and 18g, respectively. The maximum normal center-of-gravity acceleration for configuration 2 which was landed only on the hard clay-gravel landing surface was approximately 19g. Accelerations for configuration 2 were generally equal to or lower than accelerations for configuration 1 and normal. [Entire movie available on DVD from CASI as Doc ID 20070030975. Contact help@sti.nasa.gov

1965-01-01

302

Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model  

Microsoft Academic Search

Modeling land use scenario changes and its potential impact on the ecosystem structure and functioning in typical region are helpful to understand the reciprocal mechanism between land use system and ecosystem. A land use scenario dynamics model (LUSD) by the integration of system dynamics (SD) model and cellular automata (CA) model is developed with land use scenario changes in China

Chunyang He; Yaozhong Pan; Peijun Shi; Xiaobing Li; Jin Chen; Yuechen Li; Jinggang Li

2004-01-01

303

Modular Building Blocks for Manned Spacecraft: A Case Study for Moon and Mars Landing Systems  

E-print Network

Modular Building Blocks for Manned Spacecraft: A Case Study for Moon and Mars Landing Systems modular building blocks for platforming of manned Moon and Mars landing systems employing modularity. The motivation for platforming is the need to reduce overall Moon and Mars exploration architecture lifecycle

de Weck, Olivier L.

304

LUBBOCK LAND TREATMENT SYSTEM RESEARCH AND DEMONSTRATION PROJECT. VOLUME 1. DEMONSTRATION/HYDROGEOLOGIC STUDY  

EPA Science Inventory

The Lubbock Land Treatment System Research and Demonstration Project, funded by Congress in 1978 (H.R. 9375), was designed to address the various issues concerning the use of slow rate land application of municipal wastewater. Information provided in the volume details the system...

305

Participatory modeling of endangered wildlife systems: Simulating the sage-grouse and land use in  

E-print Network

METHODS Participatory modeling of endangered wildlife systems: Simulating the sage-grouse and land 2008 The Greater sage-grouse (Centrocercus urophasianus) occupies the sage brush habitats of Western for system dynamics to synthesize known sage-grouse dynamics and local land use patterns to support

Ford, Andrew

306

GEOGRAPHICAL INFORMATION SYSTEMS AND REMOTE SENSING: TOWARDS THE BETTER INTEGRATION OF DATA FOR LAND RESOURCE MANAGEMENT  

Microsoft Academic Search

The value of geographical information systems and remote sensing as tools for land and resource management is now widely recognised and their application well documented. Better integration of the technologies offers the potential, however, for developing more powerful and useful tools for land and resource management. This paper focuses on the integration of image data with geographical information systems and

Q. Zhou; B. J. Garner

1990-01-01

307

A Terminal Descent Sensor Trade Study Overview for the Orion Landing and Recovery System  

NASA Technical Reports Server (NTRS)

This trade study was conducted as a part of the Orion Landing System Advanced Development Project to determine possible Terminal Descent Sensor (TDS) architectures that could be used for a rocket assisted landing system. Several technologies were considered for the Orion TDS including radar, lidar, GPS applications, mechanical sensors, and gamma ray altimetry.

Dunn, Catherine; Prakash, Ravi

2008-01-01

308

Cross-Site Comparison of Land-Use Decision-Making and Its Consequences across Land Systems with a Generalized Agent-Based Model  

PubMed Central

Local changes in land use result from the decisions and actions of land-users within land systems, which are structured by local and global environmental, economic, political, and cultural contexts. Such cross-scale causation presents a major challenge for developing a general understanding of how local decision-making shapes land-use changes at the global scale. This paper implements a generalized agent-based model (ABM) as a virtual laboratory to explore how global and local processes influence the land-use and livelihood decisions of local land-users, operationalized as settlement-level agents, across the landscapes of six real-world test sites. Test sites were chosen in USA, Laos, and China to capture globally-significant variation in population density, market influence, and environmental conditions, with land systems ranging from swidden to commercial agriculture. Publicly available global data were integrated into the ABM to model cross-scale effects of economic globalization on local land-use decisions. A suite of statistics was developed to assess the accuracy of model-predicted land-use outcomes relative to observed and random (i.e. null model) landscapes. At four of six sites, where environmental and demographic forces were important constraints on land-use choices, modeled land-use outcomes were more similar to those observed across sites than the null model. At the two sites in which market forces significantly influenced land-use and livelihood decisions, the model was a poorer predictor of land-use outcomes than the null model. Model successes and failures in simulating real-world land-use patterns enabled the testing of hypotheses on land-use decision-making and yielded insights on the importance of missing mechanisms. The virtual laboratory approach provides a practical framework for systematic improvement of both theory and predictive skill in land change science based on a continual process of experimentation and model enhancement. PMID:24489696

Magliocca, Nicholas R.; Brown, Daniel G.; Ellis, Erle C.

2014-01-01

309

Cross-site comparison of land-use decision-making and its consequences across land systems with a generalized agent-based model.  

PubMed

Local changes in land use result from the decisions and actions of land-users within land systems, which are structured by local and global environmental, economic, political, and cultural contexts. Such cross-scale causation presents a major challenge for developing a general understanding of how local decision-making shapes land-use changes at the global scale. This paper implements a generalized agent-based model (ABM) as a virtual laboratory to explore how global and local processes influence the land-use and livelihood decisions of local land-users, operationalized as settlement-level agents, across the landscapes of six real-world test sites. Test sites were chosen in USA, Laos, and China to capture globally-significant variation in population density, market influence, and environmental conditions, with land systems ranging from swidden to commercial agriculture. Publicly available global data were integrated into the ABM to model cross-scale effects of economic globalization on local land-use decisions. A suite of statistics was developed to assess the accuracy of model-predicted land-use outcomes relative to observed and random (i.e. null model) landscapes. At four of six sites, where environmental and demographic forces were important constraints on land-use choices, modeled land-use outcomes were more similar to those observed across sites than the null model. At the two sites in which market forces significantly influenced land-use and livelihood decisions, the model was a poorer predictor of land-use outcomes than the null model. Model successes and failures in simulating real-world land-use patterns enabled the testing of hypotheses on land-use decision-making and yielded insights on the importance of missing mechanisms. The virtual laboratory approach provides a practical framework for systematic improvement of both theory and predictive skill in land change science based on a continual process of experimentation and model enhancement. PMID:24489696

Magliocca, Nicholas R; Brown, Daniel G; Ellis, Erle C

2014-01-01

310

Oil Price Effects on Land Use Competition – An Empirical Analysis  

Microsoft Academic Search

The increasing use of food commodities for biofuel production has substantial impact on prices and quantities of these and other food commodities. It is therefore likely that this trend also intensifies the competition for arable land. However, evidence for this hypothesis is generated by calibrated models while empirical evidence is rare. In this paper we analyze the effects of crude

Matthias Diermeier; Torsten Schmidt

2012-01-01

311

Exploitation of GeoEye-1 Data for Land Use/Land Cover Analysis Using Object-Based Image Analysis in the Eastern Nile Basin of Sudan  

NASA Astrophysics Data System (ADS)

Recently, object-oriented classification techniques based on image segmentation approaches are being studied using high-resolution satellite images to extract various thematic information. In this study different types of land use/land cover (LULC) types were analysed by employing object-based image analysis approach to GeoEye-1 data at the Eastern Nile Basin of Sudan. For that purpose, multi-resolution segmentation (MRS) of the Definiens software was used for creating the image objects. Using the feature space optimisation (FSO) tool the attributes of the GeoEye-1 image were optimised in order to obtain the best separability among classes for the LULC mapping. The best separation distance of the tested spectral, shape and textural features showed different variations among the discriminated LULC classes. An overall accuracy of 94 % with a kappa value 0.92 was resulted from the classification scheme, while accuracy differences among the classes were kept minimal. Finally, the results highlighted the importance of using very high-resolution satellite images for delineating the complex land use cover in the dry lands of the Eastern Nile Basin. Key Words: Multi-resolution segmentation; feature space optimisation; land use/land cover mapping; Eastern Nile Basin

Guma Biro Turk, Khalid; Pradhan, Biswajeet

312

A land use and environmental impact analysis of the Norfolk-Portsmouth SMSA  

NASA Technical Reports Server (NTRS)

The feasibility of using remote sensing techniques for land use and environmental assessment in the Norfolk-Portsmouth area is discussed. Data cover the use of high altitude aircraft and satellite remote sensing data for: (1) identifying various heirarchial levels of land use, (2) monitoring land use changes for repetitive basis, (3) assessing the impact of competing land uses, and (4) identifying areas of potential environmental deterioration. High altitude aircraft photographs (scale 1:120,000) acquired in 1959, 1970, and 1972, plus Earth Resources Technology Satellite (ERTS-1) color composite images acquired in 1972 were used for the land use and environmental assessments. The high altitude aircraft photography, as expected, was successfully used to map Level 1, Level 2, as well as some urban Level 3 land use categories. However, the detail of land use analysis obtainable from the ERTS imagery exceeded the expectations for the U.S. Geological Survey's land use classification scheme. Study results are consistent with the initial investigation which determined Level 1 land use change to be 16.7 square km per year.

Mitchel, W. B.; Berlin, G. L.

1973-01-01

313

Coal systems analysis  

Microsoft Academic Search

This collection of papers provides an introduction to the concept of coal systems analysis and contains examples of how coal systems analysis can be used to understand, characterize, and evaluate coal and coal gas resources. Chapter are: Coal systems analysis: A new approach to the understanding of coal formation, coal quality and environmental considerations, and coal as a source rock

2005-01-01

314

Application of spatial features to satellite land-use analysis. [spectral signature variations  

NASA Technical Reports Server (NTRS)

A Level I land-use analysis of selected training areas of the Colorado Front Range was carried out using digital ERTS-A satellite imagery. Level I land-use categories included urban, agriculture (irrigated and dryland farming), rangeland, and forests. The spatial variations in spectral response for these land-use classes were analyzed using discrete two-dimensional Fourier transforms to isolate and extract spatial features. Analysis was performed on ERTS frame 1352-17134 (July 10, 1973) and frame number 1388-17131 (August 15, 1973). On training sets, spatial features yielded 80 to 100 percent classification accuracies with commission errors ranging from 0 to 20 percent.

Smith, J.; Hornung, R.; Berry, J.

1975-01-01

315

Demand Analysis Concerning the Promised Land White and Chocolate Milk Brands in Texas  

E-print Network

of respondents who purchased Promised Land were included, while minimizing the number of zero observations. The Tobit model (Tobin 1958) was used on the analysis due to the 11 presence of a large number of zero observations (a censored sample of observations... correlated with each other. As a result, collinearity was not an issue. Consequently, the white milk price variables used in the analysis were: Borden, Oak Farms, Poinsettia, Promised Land, Horizon Organic, Schepps, and private label brands (see table 3...

Bingham, David Eldon

2013-05-03

316

Anticipating Forest and Range Land Development in Central Oregon (USA) for Landscape Analysis, with an Example Application Involving Mule Deer  

NASA Astrophysics Data System (ADS)

Forest policymakers, public lands managers, and scientists in the Pacific Northwest (USA) seek ways to evaluate the landscape-level effects of policies and management through the multidisciplinary development and application of spatially explicit methods and models. The Interagency Mapping and Analysis Project (IMAP) is an ongoing effort to generate landscape-wide vegetation data and models to evaluate the integrated effects of disturbances and management activities on natural resource conditions in Oregon and Washington (USA). In this initial analysis, we characterized the spatial distribution of forest and range land development in a four-county pilot study region in central Oregon. The empirical model describes the spatial distribution of buildings and new building construction as a function of population growth, existing development, topography, land-use zoning, and other factors. We used the model to create geographic information system maps of likely future development based on human population projections to inform complementary landscape analyses underway involving vegetation, habitat, and wildfire interactions. In an example application, we use the model and resulting maps to show the potential impacts of future forest and range land development on mule deer ( Odocoileus hemionus) winter range. Results indicate significant development encroachment and habitat loss already in 2000 with development located along key migration routes and increasing through the projection period to 2040. The example application illustrates a simple way for policymakers and public lands managers to combine existing data and preliminary model outputs to begin to consider the potential effects of development on future landscape conditions.

Kline, Jeffrey D.; Moses, Alissa; Burcsu, Theresa

2010-05-01

317

Anticipating forest and range land development in central Oregon (USA) for landscape analysis, with an example application involving mule deer.  

PubMed

Forest policymakers, public lands managers, and scientists in the Pacific Northwest (USA) seek ways to evaluate the landscape-level effects of policies and management through the multidisciplinary development and application of spatially explicit methods and models. The Interagency Mapping and Analysis Project (IMAP) is an ongoing effort to generate landscape-wide vegetation data and models to evaluate the integrated effects of disturbances and management activities on natural resource conditions in Oregon and Washington (USA). In this initial analysis, we characterized the spatial distribution of forest and range land development in a four-county pilot study region in central Oregon. The empirical model describes the spatial distribution of buildings and new building construction as a function of population growth, existing development, topography, land-use zoning, and other factors. We used the model to create geographic information system maps of likely future development based on human population projections to inform complementary landscape analyses underway involving vegetation, habitat, and wildfire interactions. In an example application, we use the model and resulting maps to show the potential impacts of future forest and range land development on mule deer (Odocoileus hemionus) winter range. Results indicate significant development encroachment and habitat loss already in 2000 with development located along key migration routes and increasing through the projection period to 2040. The example application illustrates a simple way for policymakers and public lands managers to combine existing data and preliminary model outputs to begin to consider the potential effects of development on future landscape conditions. PMID:20300934

Kline, Jeffrey D; Moses, Alissa; Burcsu, Theresa

2010-05-01

318

Multi-Terrain Earth Landing Systems Applicable for Manned Space Capsules  

NASA Technical Reports Server (NTRS)

A key element of the President's Vision for Space Exploration is the development of a new space transportation system to replace Shuttle that will enable manned exploration of the moon, Mars, and beyond. NASA has tasked the Constellation Program with the development of this architecture, which includes the Ares launch vehicle and Orion manned spacecraft. The Orion spacecraft must carry six astronauts and its primary structure should be reusable, if practical. These requirements led the Constellation Program to consider a baseline land landing on return to earth. To assess the landing system options for Orion, a review of current operational parachute landing systems such as those used for the F-111 escape module and the Soyuz is performed. In particular, landing systems with airbags and retrorockets that would enable reusability of the Orion capsule are investigated. In addition, Apollo tests and analyses conducted in the 1960's for both water and land landings are reviewed. Finally, tests and dynamic finite element simulations to understand land landings for the Orion spacecraft are also presented.

Fasanella, Edwin L.

2008-01-01

319

Multi-Terrain Earth Landing Systems Applicable for Manned Space Capsules  

NASA Technical Reports Server (NTRS)

A key element of the President's Vision for Space Exploration is the development of a new space transportation system to replace the Shuttle that will enable manned exploration of the moon, Mars, and beyond. NASA has tasked the Constellation Program with the development of this architecture, which includes the Ares launch vehicle and Orion manned spacecraft. The Orion spacecraft must carry six astronauts and its primary structure should be reusable, if practical. These requirements led the Constellation Program to consider a baseline land landing on return to earth. To assess the landing system options for Orion, a review of current operational parachute landing systems such as those used for the F-111 escape module and the Soyuz is performed. In particular, landing systems with airbags and retrorockets that would enable reusability of the Orion capsule are investigated. In addition, Apollo tests and analyses conducted in the 1960's for both water and land landings are reviewed. Finally, tests and dynamic finite element simulations to understand land landings for the Orion spacecraft are also presented.

Fasanella, Edwin L.

2008-01-01

320

Off-Axis Calibration of KamLAND and Modeling of the ``FourPi'' Calibration System  

NASA Astrophysics Data System (ADS)

KamLAND is 1000-ton liquid scintillator detector which uses the prompt and delayed signals from inverse beta decay to detect electron anti-neutrinos produced in nuclear reactors. KamLAND has made the first observation of the disappearance of reactor electron anti-neutrinos. The largest contribution to the systematic uncertainty in KamLAND is the fiducial volume uncertainty (4.7 % out of a total 6.5 % ). Until now the detector has been calibrated using gamma-ray sources of known energy deployed along the detector's vertical axis. A new 4? calibration system allows for off-axis source deployment throughout the entire fiducial volume. The 4 ? system is expected to reduce the fiducial volume uncertainty from 4.7 % to ˜ 1-2 % , and improve KamLAND's sensitivity in the determination of the mass-difference parameter ?m12^2 . The 4? system is currently in the initial stages of off-axis deployment. An off-line calculation is used to predict the location of the gamma-ray sources within the detector. The calculation takes into account the systems geometry, buoyancy effects in the liquid scintillator, and gravitational deflection of the 4? pole from its neutral axis (deflection correction incorporates both a theoretical model, and survey data). Comparison of the predicted source location with the vertex reconstructed using the KamLAND analysis software, allows for an investigation of the biases in the reconstruction procedure.

Elor, Gilly

2006-10-01

321

AGROFORESTRY SYSTEMS: INTEGRATED LAND USE TO STORE AND CONSERVE CARBON  

EPA Science Inventory

Agroforestry is a promising land use practice to maintain or increase agricultural productivity while preserving or improving fertility. n extensive literature survey was conducted to evaluate the carbon dynamics of agroforestry practices and to assess their potential to store ca...

322

Integrated dynamic landscape analysis and modeling system (IDLAMS) : programmer's manual.  

SciTech Connect

The Integrated Dynamic Landscape Analysis and Modeling System (IDLAMS) is a prototype, integrated land management technology developed through a joint effort between Argonne National Laboratory (ANL) and the US Army Corps of Engineers Construction Engineering Research Laboratories (USACERL). Dr. Ronald C. Sundell, Ms. Pamela J. Sydelko, and Ms. Kimberly A. Majerus were the principal investigators (PIs) for this project. Dr. Zhian Li was the primary software developer. Dr. Jeffrey M. Keisler, Mr. Christopher M. Klaus, and Mr. Michael C. Vogt developed the decision analysis component of this project. It was developed with funding support from the Strategic Environmental Research and Development Program (SERDP), a land/environmental stewardship research program with participation from the US Department of Defense (DoD), the US Department of Energy (DOE), and the US Environmental Protection Agency (EPA). IDLAMS predicts land conditions (e.g., vegetation, wildlife habitats, and erosion status) by simulating changes in military land ecosystems for given training intensities and land management practices. It can be used by military land managers to help predict the future ecological condition for a given land use based on land management scenarios of various levels of training intensity. It also can be used as a tool to help land managers compare different land management practices and further determine a set of land management activities and prescriptions that best suit the needs of a specific military installation.

Klaus, C. M.; Li, Z.; Majerus, K. A.; Sundell, R. C.; Sydelko, P. J.; Vogt, M. C.

1999-02-24

323

Classification of urban land cover based on expert systems, object models and texture  

Microsoft Academic Search

The application of intelligent systems within the field of remote sensing is reviewed with special reference to urban land cover mapping from digital satellite imagery. Urban areas constitute spectrally heterogenous land-cover classes and call for the application of intelligent, texture-based image processing methods. The appearance of an urban land-cover class in a digital image generated by remote sensing is closely

Lasse Moller-Jensen

1997-01-01

324

System architecture and market aspects of an European Land Mobile Satellite System via EMS  

NASA Astrophysics Data System (ADS)

The paper describes an implementation scenario of a Land Mobile Satellite System via the EMS (European Mobile System) payload embarked on Italsat F-2. Some emphasis is given on market issues aiming at singling out business niches of Land Mobile Satellite Services (LMSS) in Europe. Other crucial issues exist such as: the alternate/competitive systems, the problems of interworking with other existing and/or planned systems, the definition of network architecture that better fits the user requirements, the marketing strategy and, last but not least, the financial evaluation of the project. The paper, on the basis of a study performed by Telespazio on behalf of ESA, discusses some of these issues with emphasis on competitive market aspects.

Ananasso, F.; Mistretta, I.

1992-03-01

325

Preliminary Analysis of the efficacy of Artificial neural Network (ANN) and Cellular Automaton (CA) based Land Use Models in Urban Land-Use Planning  

NASA Astrophysics Data System (ADS)

This research provides an opportunity of collaboration between urban planners and modellers by providing a clear theoretical foundations on the two most widely used urban land use models, and assessing the effectiveness of applying the models in urban planning context. Understanding urban land cover change is an essential element for sustainable urban development as it affects ecological functioning in urban ecosystem. Rapid urbanization due to growing inclination of people to settle in urban areas has increased the complexities in predicting that at what shape and size cities will grow. The dynamic changes in the spatial pattern of urban landscapes has exposed the policy makers and environmental scientists to great challenge. But geographic science has grown in symmetry to the advancements in computer science. Models and tools are developed to support urban planning by analyzing the causes and consequences of land use changes and project the future. Of all the different types of land use models available in recent days, it has been found by researchers that the most frequently used models are Cellular Automaton (CA) and Artificial Neural Networks (ANN) models. But studies have demonstrated that the existing land use models have not been able to meet the needs of planners and policy makers. There are two primary causes identified behind this prologue. First, there is inadequate understanding of the fundamental theories and application of the models in urban planning context i.e., there is a gap in communication between modellers and urban planners. Second, the existing models exclude many key drivers in the process of simplification of the complex urban system that guide urban spatial pattern. Thus the models end up being effective in assessing the impacts of certain land use policies, but cannot contribute in new policy formulation. This paper is an attempt to increase the knowledge base of planners on the most frequently used land use model and also assess the relative effectiveness of the two models, ANN and CA, in urban planning. The questions that are addressed in this research are: a) What makes ANN models different from CA models?; b) Which model has higher accuracy in predicting future urban land use change?; and c) Are the models effective enough in guiding urban land use policies and strategies? The models that are used for this research are Multilayer Perceptron (MLP) and CA model, available in IDRISI Taiga. Since, the objective is to perform a comparative analysis and draw general inferences irrespective of specific urban policies, the availability of data was given more emphasis over the selection of particular location. Urban area in Massachusetts was chosen to conduct the study due to data availability. Extensive literature review was performed to understand the functionality of the two models. The models were applied to predict future changes and the accuracy assessment was performed using standard matrix. Inferences were drawn about the applicability of the models in urban planning context along with recommendations. This research will not only develop understanding of land use models among urban planners, but also will create an environment of coupled research between planners and modellers.

Harun, R.

2013-05-01

326

Development and Flight Testing of an Autonomous Landing Gear Health-Monitoring System  

NASA Technical Reports Server (NTRS)

Development and testing of an adaptable vehicle health-monitoring architecture is presented. The architecture is being developed for a fleet of vehicles. It has three operational levels: one or more remote data acquisition units located throughout the vehicle; a command and control unit located within the vehicle; and, a terminal collection unit to collect analysis results from all vehicles. Each level is capable of performing autonomous analysis with a trained expert system. Communication between all levels is done with wireless radio frequency interfaces. The remote data acquisition unit has an eight channel programmable digital interface that allows the user discretion for choosing type of sensors; number of sensors, sensor sampling rate and sampling duration for each sensor. The architecture provides framework for a tributary analysis. All measurements at the lowest operational level are reduced to provide analysis results necessary to gauge changes from established baselines. These are then collected at the next level to identify any global trends or common features from the prior level. This process is repeated until the results are reduced at the highest operational level. In the framework, only analysis results are forwarded to the next level to reduce telemetry congestion. The system's remote data acquisition hardware and non-analysis software have been flight tested on the NASA Langley B757's main landing gear. The flight tests were performed to validate the following: the wireless radio frequency communication capabilities of the system, the hardware design, command and control; software operation; and, data acquisition, storage and retrieval.

Woodard, Stanley E.; Coffey, Neil C.; Gonzalez, Guillermo A.; Taylor, B. Douglas; Brett, Rube R.; Woodman, Keith L.; Weathered, Brenton W.; Rollins, Courtney H.

2003-01-01

327

23 CFR 972.212 - Federal lands safety management system (SMS).  

Code of Federal Regulations, 2011 CFR

...LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems...responsible for the roadway, human, and vehicle safety elements...and countermeasures which affect safety on the FWS...

2011-04-01

328

23 CFR 972.212 - Federal lands safety management system (SMS).  

Code of Federal Regulations, 2013 CFR

...LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems...responsible for the roadway, human, and vehicle safety elements...and countermeasures which affect safety on the FWS...

2013-04-01

329

23 CFR 972.212 - Federal lands safety management system (SMS).  

Code of Federal Regulations, 2012 CFR

...LANDS HIGHWAYS FISH AND WILDLIFE SERVICE MANAGEMENT SYSTEMS Fish and Wildlife Service Management Systems...responsible for the roadway, human, and vehicle safety elements...and countermeasures which affect safety on the FWS...

2012-04-01

330

77 FR 472 - National Advisory Committee for Implementation of the National Forest System Land Management...  

Federal Register 2010, 2011, 2012, 2013

...Implementation of the National Forest System Land Management Planning Rule; Correction AGENCY: USDA Forest Service...Forest Service, National Forest System, Ecosystem Management Coordination; telephone: (202) 205-0830,...

2012-01-05

331

Agent-based Housing Market Microsimulation for Integrated Land Use, Transportation, Environment Model System  

E-print Network

The Housing Market Evolutionary System (HoMES) is the updated housing market module for the Integrated Land Use, Transportation, Environment (ILUTE) model system. HoMES is a disaggregate, agent-based microsimulation of the ...

Rosenfield, Adam

332

Towards decision-based global land use models for improved understanding of the Earth system  

NASA Astrophysics Data System (ADS)

A primary goal of Earth system modelling is to improve understanding of the interactions and feedbacks between human decision making and biophysical processes. The nexus of land use and land cover change (LULCC) and the climate system is an important example. LULCC contributes to global and regional climate change, while climate affects the functioning of terrestrial ecosystems and LULCC. However, at present, LULCC is poorly represented in Global Circulation Models (GCMs). LULCC models that are explicit about human behaviour and decision making processes have been developed at local to regional scales, but the principles of these approaches have not yet been applied to the global scale level in ways that deal adequately with both direct and indirect feedbacks from the climate system. In this article, we explore current knowledge about LULCC modelling and the interactions between LULCC, GCMs and Dynamic Global Vegetation Models (DGVMs). In doing so, we propose new ways forward for improving LULCC representations in Earth System Models. We conclude that LULCC models need to better conceptualise the alternatives for up-scaling from the local to global. This involves better representation of human agency, including processes such as learning, adaptation and agent evolution, formalising the role and emergence of governance structures, institutional arrangements and policy as endogenous processes and better theorising about the role of tele-connections and connectivity across global networks. Our analysis underlines the importance of observational data in global scale assessments and the need for coordination in synthesising and assimilating available data.

Rounsevell, M. D. A.; Arneth, A.; Alexander, P.; Brown, D. G.; de Noblet-Ducoudré, N.; Ellis, E.; Finnigan, J.; Galvin, K.; Grigg, N.; Harman, I.; Lennox, J.; Magliocca, N.; Parker, D.; O'Neill, B. C.; Verburg, P. H.; Young, O.

2013-08-01

333

Towards decision-based global land use models for improved understanding of the Earth system  

NASA Astrophysics Data System (ADS)

A primary goal of Earth system modelling is to improve understanding of the interactions and feedbacks between human decision making and biophysical processes. The nexus of land use and land cover change (LULCC) and the climate system is an important example. LULCC contributes to global and regional climate change, while climate affects the functioning of terrestrial ecosystems and LULCC. However, at present, LULCC is poorly represented in global circulation models (GCMs). LULCC models that are explicit about human behaviour and decision-making processes have been developed at local to regional scales, but the principles of these approaches have not yet been applied to the global scale level in ways that deal adequately with both direct and indirect feedbacks from the climate system. In this article, we explore current knowledge about LULCC modelling and the interactions between LULCC, GCMs and dynamic global vegetation models (DGVMs). In doing so, we propose new ways forward for improving LULCC representations in Earth system models. We conclude that LULCC models need to better conceptualise the alternatives for upscaling from the local to global scale. This involves better representation of human agency, including processes such as learning, adaptation and agent evolution, formalising the role and emergence of governance structures, institutional arrangements and policy as endogenous processes and better theorising about the role of teleconnections and connectivity across global networks. Our analysis underlines the importance of observational data in global-scale assessments and the need for coordination in synthesising and assimilating available data.

Rounsevell, M. D. A.; Arneth, A.; Alexander, P.; Brown, D. G.; de Noblet-Ducoudré, N.; Ellis, E.; Finnigan, J.; Galvin, K.; Grigg, N.; Harman, I.; Lennox, J.; Magliocca, N.; Parker, D.; O'Neill, B. C.; Verburg, P. H.; Young, O.

2014-02-01

334

Modeling the influences of land reclamation on groundwater systems: A case study in Shekou peninsula, Shenzhen, China  

E-print Network

Modeling the influences of land reclamation on groundwater systems: A case study in Shekou form 16 February 2010 Accepted 18 April 2010 Available online 24 April 2010 Keywords: Land reclamation of land has been reclaimed around the Shekou peninsula, Shenzhen, China. Land reclamation may have

Jiao, Jiu Jimmy

335

Message handling system concepts and services in a land mobile satellite system  

NASA Technical Reports Server (NTRS)

A network architecture containing the capabilities offered by the Message Handling System (MHS) to the PRODAT Land Mobile Satellite System (LMSS) is described taking into account the constraints of a preexisting satellite system which is going to become operational. The mapping between MHS services and PRODAT requirements is also reported and shows that the supplied performance can be significantly enhanced to both fixed and mobile users. The impact of the insertion of additional features on the system structure, especially on the centralized control unit, are also addressed.

Barberis, S.; Settimo, F.; Giralda, A.; Mistretta, I.; Loisy, C.; Parmentier, J. L.

1990-01-01

336

Measures to Enhance Trust in Land Administration Systems and Engender their Proper Use  

Microsoft Academic Search

SUMMARY Land administration systems (LAS) carry out a number of tasks, including land registration, maintaining cadastral records, granting spatial planning consents, real estate taxation, and valuation. These are not ends in themselves but means to an end. The argument put forward in this paper is that, whilst markets are not perfect, they are the most efficient means of allocating resources

Richard GROVER

337

Decision Support Systems (DSSs) For Contaminated Land Management - Gaps And Challenges  

EPA Science Inventory

A plethora of information is available when considering decision support systems for risk-based management of contaminated land. Broad issues of what is contaminated land, what is a brownfield, and what is remediation are discussed in EU countries and the U.S. Making decisions ...

338

RECONSTRUCTION OF LAND ADMINISTRATION SYSTEM IN NANGGROE ACEH DARUSSALAM (NAD) AND NIAS  

Microsoft Academic Search

SUMMARY: Indeed the earthquakes and tsunami that thoroughly shattered part of Aceh and Nias in North Sumatra brought particular damage to property rights marks and to the land administration system in general. Land rights recovery and protection, therefore, are necessary and should be recovered as soon as soon as possible. In this situation the role of BPN, as an organization

Joyo WINOTO

339

A global observing system for the validation of space-borne land observations  

Microsoft Academic Search

Under NASA's Earth Observing System (EOS) framework, EOS instrument science teams share responsibility with independently selected scientists for the validation of EOS land products. In 1997, these groups began developing the infrastructure and resources for a global effort of systematic measurements under the leadership of the MODIS Land Science Team. The project is anchored by 25 Core Sites for which

J. Privette; J. Morisette; C. Justice

2002-01-01

340

REPRESENTATION OF HETEROGENEITY EFFECTS IN EARTH SYSTEM MODELING: EXPERIENCE FROM LAND SURFACE MODELING  

Microsoft Academic Search

The land surface is characterized by pro- nounced spatial heterogeneity that spans a wide range of scales. This heterogeneity affects the surface energy and water budgets, as well as the land-atmosphere exchanges of momentum, heat, water and other constituents, through a number of highly nonlinear processes. The resolution of present-day Earth (or climate) system models is still too coarse to

Filippo Giorgi

341

Representation of heterogeneity effects in earth system modeling: Experience from land surface modeling  

Microsoft Academic Search

The land surface is characterized by pronounced spatial heterogeneity that spans a wide range of scales. This heterogeneity affects the surface energy and water budgets, as well as the land-atmosphere exchanges of momentum, heat, water and other constituents, through a number of highly nonlinear processes. The resolution of present-day Earth (or climate) system models is still too coarse to explicitly

Filippo Giorgi; Roni Avissar

1997-01-01

342

Representation of heterogeneity effects in Earth system modeling: Experience from land surface modeling  

Microsoft Academic Search

The land surface is characterized by pronounced spatial heterogeneity that spans a wide range of scales. This heterogeneity affects the surface energy and water budgets, as well as the land-atmosphere exchanges of momentum, heat, water and other constituents, through a number of highly nonlinear processes. The resolution of present-day Earth (or climate) system models is still too coarse to explicitly

Filippo Giorgi; Roni Avissar

1997-01-01

343

LUBBOCK LAND TREATMENT SYSTEM RESEARCH AND DEMONSTRATION PROJECT. VOLUME 3. AGRICULTURAL RESEARCH STUDY  

EPA Science Inventory

The Lubbock Land Treatment System Research and Demonstration Project, funded by Congress in 1978 (H.R. 9375), was designed to address the various issues concerning the use of slow rate land application of municipal wastewater. The volume details the agricultural research program ...

344

Assessment of snow modeling in the North American land data assimilation system (NLDAS)  

Microsoft Academic Search

This study assesses the cold season process modeling in the North American Land Data Assimilation System (NLDAS). Simulations from the four land surface models (Noah, MOSAIC, SAC and VIC) in the NLDAS are compared with observational data for a 3-year retrospective period over the USA. Observed snow cover extent data are from the IMS (Interactive Multisensor Snow and Ice Mapping

M. Pan

2003-01-01

345

Spatio-temporal variations of soil nutrients influenced by an altered land tenure system in China  

E-print Network

Spatio-temporal variations of soil nutrients influenced by an altered land tenure system in China Key Lab of Subtropical Soil Science and Plant Nutrition, Institute of Soil and Water Resources and Environmental Science, Zhejiang University, Hangzhou 310029, China b Department of Land Management, Zhejiang

Zhang, Minghua

346

FORT HOOD LAND MANAGEMENT SYSTEM (LMS) MILITARY FIELD APPLICATION SITE FY99 IN-PROGRESS REVIEW  

EPA Science Inventory

The purpose of the Land Management System (LMS) is to provide relevant science, tools, and information to land and water resource managers and decision makers with the goal of enhancing their ability to understand and communicate past, current, and potential impacts of management...

347

Closed loop analysis of manual flare and landing. [aircraft maneuvers simulation  

NASA Technical Reports Server (NTRS)

This paper describes an approach to analyzing the manual flare and landing of an airplane. The basis of this approach is a mathematical model of the flare maneuver which is derived from manual landings of both real and simulated aircraft. This flare model in turn lends itself to a linear closed loop system description of the combined pilot/vehicle. Furthermore, simple Laplace transform methods can be used to map flare performance as functions of the flare maneuver. Having this link between flare maneuver and landing performance, we can estimate the pilot's ease in achieving desired levels of landing performance. Examples of this approach will be given using the results of a STOL airplane approach and landing simulation.

Heffley, R. K.

1974-01-01

348

Spatio-temporal analysis of changes in land use through remotely sensed imagery  

NASA Astrophysics Data System (ADS)

Over the last decades Spanish rural and littoral areas have undergone a significant transformation. This process, affecting the use of land mainly, is even more obvious in periurban areas. It is along these areas where the process of urban expansion makes it difficult to combine the use of land in these regions, which, being basically agricultural in nature, become deeply influenced by neighbouring urban spaces. Remote sensing appears as an invaluable resource in this context of territory transformation processes. Monitoring techniques based on multispectral satellite-acquired data have demonstrated potential as a means to detect, identify, and map changes in land use. We have developed a methodology to map and monitor land cover change using multitemporal Landsat Thematic Mapper (TM) data in the are of Granada for 1998 and 2002. Various types of techniques have been used, both quantitative and of image comparison: difference between images, multitemporal quotients, main component analysis (MCA), multitemporal vectors, and multitemporal analysis of classified images. The results quantify the land cover change patterns in the metropolitan area and demonstrate the potential of multitemporal Landsat data to provide an accurate, economical means to map and analyze changes in land cover over time that can be used as inputs to land management and policy decisions.

Rodríguez-Galiano, Víctor; Chica-Olmo, Mario; Garcia-Soldado, Maria José

349

Dust in the Earth system: the biogeochemical linking of land, air and sea.  

PubMed

Understanding the response of the Earth's climate system to anthropogenic perturbation has been a pressing priority for society since the late 1980s. However, recent years have seen a major paradigm shift in how such an understanding can be reached. Climate change demands analysis within an integrated 'Earth-system' framework, taken to encompass the suite of interacting physical, chemical, biological and human processes that, in transporting and transforming materials and energy, jointly determine the conditions for life on the whole planet. This is a highly complex system, characterized by multiple nonlinear responses and thresholds, with linkages often between apparently disparate components. The interconnected nature of the Earth system is wonderfully illustrated by the diverse roles played by atmospheric transport of mineral 'dust', particularly in its capacity as a key pathway for the delivery of nutrients essential to plant growth, not only on land, but perhaps more importantly, in the ocean. Dust therefore biogeochemically links land, air and sea. This paper reviews the biogeochemical role of mineral dust in the Earth system and its interaction with climate, and, in particular, the potential importance of both past and possible future changes in aeolian delivery of the micro-nutrient iron to the ocean. For instance, if, in the future, there was to be a widespread stabilization of soils for the purpose of carbon sequestration on land, a reduction in aeolian iron supply to the open ocean would occur. The resultant weakening of the oceanic carbon sink could potentially offset much of the carbon sequestered on land. In contrast, during glacial times, enhanced dust supply to the ocean could have 'fertilized' the biota and driven atmospheric CO(2) lower. Dust might even play an active role in driving climatic change; since changes in dust supply may affect climate, and changes in climate, in turn, influence dust, a 'feedback loop' is formed. Possible feedback mechanisms are identified, recognition of whose operation could be crucial to our understanding of major climatic transitions over the past few million years. PMID:12626273

Ridgwell, Andy J

2002-12-15

350

Space shuttle navigation analysis. Volume 2: Baseline system navigation  

NASA Technical Reports Server (NTRS)

Studies related to the baseline navigation system for the orbiter are presented. The baseline navigation system studies include a covariance analysis of the Inertial Measurement Unit calibration and alignment procedures, postflight IMU error recovery for the approach and landing phases, on-orbit calibration of IMU instrument biases, and a covariance analysis of entry and prelaunch navigation system performance.

Jones, H. L.; Luders, G.; Matchett, G. A.; Rains, R. G.

1980-01-01

351

Atmosphere, ocean, and land: Critical gaps in Earth system models  

NASA Technical Reports Server (NTRS)

We briefly review current knowledge and pinpoint some of the major areas of uncertainty for the following fundamental processes: (1) convection, condensation nuclei, and cloud formation; (2) oceanic circulation and its coupling to the atmosphere and cryosphere; (3) land surface hydrology and hydrology-vegetation coupling; (4) biogeochemistry of greenhouse gases; and (5) upper atmospheric chemistry and circulation.

Prinn, Ronald G.; Hartley, Dana

1992-01-01

352

Application of learning management system (LMS) to the learning of land evaluation  

NASA Astrophysics Data System (ADS)

The adaptation of the Universities to European Higher Education Area (EHEA) is producing changes in the learning system. One of the new learning system is the use of Moodle which is an Open Source Course Management System (CMS), also known as a Learning Management System (LMS) or a Virtual Learning Environment (VLE). It has become very popular among educators around the world as a tool for creating online dynamic web sites for their students. Professors of Soil Science Department of Universidad Politécnica de Madrid are introducing the use of moodle combined with the portfolio development in the learning of the subject of Land Evaluation. The objective of this subject is the application of the land capability system to the land evaluation of an specific area. The aim of this work is to evaluate the influence of the application of LMS in the teaching of Land Evaluation at University level.

Gascó, G.; Guerrero, F.; Gallardo, J.; Gascó, J. M.; Saa, A.

2010-05-01

353

Landscape level analysis of the spatial and temporal complexity of land-use change  

NASA Astrophysics Data System (ADS)

For understanding the causes and effects of changes in land use it is critical to study the interaction between the temporal dynamics and the spatial pattern of land use. Interactions arise from feedbacks in the human-environment system, heterogeneity in the biophysical and human environment and the influence of land-use history. Land-use simulation models can serve as a tool to understand these dynamics in more detail and assess the impact on ecosystem functioning. This chapter presents a spatially explicit modelling approach to explore the spatial and temporal changes in land-use patterns as a function of the specific characteristics of cropping systems and feedbacks between land use and the environment. A case study for Bac Kan province in northern Vietnam is used to test and illustrate the capacity of the model. The results indicate that the model can be used to assess changes in land-use pressure and pattern under different development pathways or scenario conditions. The potential of further developing this approach is discussed.

Verburg, Peter H.; Veldkamp, A.; Willemen, Louise; Overmars, Koen P.; Castella, Jean-Christophe

354

Direct Sensor Orientation of a Land-Based Mobile Mapping System  

PubMed Central

A land-based mobile mapping system (MMS) is flexible and useful for the acquisition of road environment geospatial information. It integrates a set of imaging sensors and a position and orientation system (POS). The positioning quality of such systems is highly dependent on the accuracy of the utilized POS. This limitation is the major drawback due to the elevated cost associated with high-end GPS/INS units, particularly the inertial system. The potential accuracy of the direct sensor orientation depends on the architecture and quality of the GPS/INS integration process as well as the validity of the system calibration (i.e., calibration of the individual sensors as well as the system mounting parameters). In this paper, a novel single-step procedure using integrated sensor orientation with relative orientation constraint for the estimation of the mounting parameters is introduced. A comparative analysis between the proposed single-step and the traditional two-step procedure is carried out. Moreover, the estimated mounting parameters using the different methods are used in a direct geo-referencing procedure to evaluate their performance and the feasibility of the implemented system. Experimental results show that the proposed system using single-step system calibration method can achieve high 3D positioning accuracy. PMID:22164015

Rau, Jiann-Yeou; Habib, Ayman F.; Kersting, Ana P.; Chiang, Kai-Wei; Bang, Ki-In; Tseng, Yi-Hsing; Li, Yu-Hua

2011-01-01

355

An econometric analysis of changes in arable land utilization using multinomial logit model in Pinggu district, Beijing, China.  

PubMed

Arable land in China has been decreasing as a result of rapid population growth and economic development as well as urban expansion, especially in developed regions around cities where quality farmland quickly disappears. This paper analyzed changes in arable land utilization during 1993-2008 in the Pinggu district, Beijing, China, developed a multinomial logit (MNL) model to determine spatial driving factors influencing arable land-use change, and simulated arable land transition probabilities. Land-use maps, as well as social-economic and geographical data were used in the study. The results indicated that arable land decreased significantly between 1993 and 2008. Lost arable land shifted into orchard, forestland, settlement, and transportation land. Significant differences existed for arable land transitions among different landform areas. Slope, elevation, population density, urbanization rate, distance to settlements, and distance to roadways were strong drivers influencing arable land transition to other uses. The MNL model was proved effective for predicting transition probabilities in land use from arable land to other land-use types, thus can be used for scenario analysis to develop land-use policies and land-management measures in this metropolitan area. PMID:23774750

Xu, Yueqing; McNamara, Paul; Wu, Yanfang; Dong, Yue

2013-10-15

356

Land use information extraction and spatio-temporal variation analysis of Poyang Lake Basin based on remote sensing  

NASA Astrophysics Data System (ADS)

Poyang Lake Basin is the biggest freshwater lake in China and a significant wetland of the world. The study of the land use changes on there is a great significance for regional sustainable development. In this paper, using the RS image as the main data source, the study area was divided into six land use types. With the acquired land use data of three periods, the spatio-temporal dynamic variation characteristics were analyzed with the area changes and land use dynamic index (LUDI). The analysis shows that the largest land use type is woodland, followed by cultivated land and grassland, and area of the rest types all account for less than 10%. Through the analysis of the area transfer matrix of LUCC, it shows that woodland and construction land increased in each period while cultivated land reduced. Unused land increased a lot during 1990 to 2000 before decreased dramatically during 2000 to 2008, grassland and water experienced a significant increase after an obvious decline and came out to increase finally. The analysis of LUDI indicates that construction land changed the most quickly, followed by unused land and cultivated land, yet the other land use types changed slowly.

Liu, Hai; Xia, Huiqiong; Zhou, Bo

2013-10-01

357

An economic analysis of land use alternatives on CRP land trees after the CRP contracts expire in east Texas  

E-print Network

trees to produce sawlogs or pulpwood and reverting land to crops, corn, cotton, sorghum and wheat. A generic theoretical framework is formulated to compare various land use alternatives. Several scenarios are formulated to incorporate the changing...

Arekere, Marigowda Dhananjaya

2012-06-07

358

Mars Exploration Rovers Entry, Descent, and Landing Trajectory Analysis  

NASA Technical Reports Server (NTRS)

In this study we present a novel method of land surface classification using surface-reflected GPS signals in combination with digital imagery. Two GPS-derived classification features are merged with visible image data to create terrain-moisture (TM) classes, defined here as visibly identifiable terrain or landcover classes containing a surface/soil moisture component. As compared to using surface imagery alone, classification accuracy is significantly improved for a number of visible classes when adding the GPS-based signal features. Since the strength of the reflected GPS signal is proportional to the amount of moisture in the surface, use of these GPS features provides information about the surface that is not obtainable using visible wavelengths alone. Application areas include hydrology, precision agriculture, and wetlands mapping.

Desai, Prasun N.; Knocke, Philip C.

2007-01-01

359

Enhanced Flight Vision Systems and Synthetic Vision Systems for NextGen Approach and Landing Operations  

NASA Technical Reports Server (NTRS)

Synthetic Vision Systems and Enhanced Flight Vision System (SVS/EFVS) technologies have the potential to provide additional margins of safety for aircrew performance and enable operational improvements for low visibility operations in the terminal area environment with equivalent efficiency as visual operations. To meet this potential, research is needed for effective technology development and implementation of regulatory standards and design guidance to support introduction and use of SVS/EFVS advanced cockpit vision technologies in Next Generation Air Transportation System (NextGen) operations. A fixed-base pilot-in-the-loop simulation test was conducted at NASA Langley Research Center that evaluated the use of SVS/EFVS in NextGen low visibility approach and landing operations. Twelve crews flew approach and landing operations in a simulated NextGen Chicago O'Hare environment. Various scenarios tested the potential for using EFVS to conduct approach, landing, and roll-out operations in visibility as low as 1000 feet runway visual range (RVR). Also, SVS was tested to evaluate the potential for lowering decision heights (DH) on certain instrument approach procedures below what can be flown today. Expanding the portion of the visual segment in which EFVS can be used in lieu of natural vision from 100 feet above the touchdown zone elevation to touchdown and rollout in visibilities as low as 1000 feet RVR appears to be viable as touchdown performance was acceptable without any apparent workload penalties. A lower DH of 150 feet and/or possibly reduced visibility minima using SVS appears to be viable when implemented on a Head-Up Display, but the landing data suggests further study for head-down implementations.

Kramer, Lynda J.; Bailey, Randall E.; Ellis, Kyle K. E.; Williams, Steven P.; Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Shelton, Kevin J.

2013-01-01

360

Land degradation and Poverty in maize producing areas of Kenya - Development of an interdisciplinary analysis framework using GIS and remote sensing  

NASA Astrophysics Data System (ADS)

Land degradation causes poverty and vice versa. But both processes are highly complex, hard to predict and to mitigate, and need insights from different perspectives. Therefore an interdisciplinary framework for the understanding of land degradation processes by linking biophysical data with socio-economic trends is necessary. Agricultural systems in Kenya are affected by land degradation and especially recent developments such as agricultural innovations including the use of hybrid seeds and chemical fertilizer have an impact on the environment. Vegetation analysis, used as a proxy indicator for the status of land is carried out to monitor environmental changes in maize producing areas of western Kenya. One of the methods used in this study includes time series analysis of vegetation data from 2001 to 2010 based on MODIS NDVI data with 250m and 500m resolution. Occurring trends are linked to rainfall estimation data and annually classified land use cover data with 500m resolution based on MODIS within the same time period. Analysis of significant trends in combination with land cover information show recent land change dynamics. As these changes are not solely biophysically driven, socio-economic variables representing marginality - defined as the root cause of poverty- are also considered. The most poor are primarily facing the most vulnerable and thereby less fertile soils. Moreover they are lacking access to information to eventually use existing potential. This makes the analysis of changing environmental processes and household characteristics in the interplay important to understand in order to highlight the most influencing variables. Within the new interdisciplinary analysis framework the concept of marginality includes different dimensions referring to certain livelihood characteristics such as health and education which describe a more diverse picture of poverty than the known economic perspective. Household surveys and census data from different time periods allow the analysis of socio-economic trends and link this information to biophysical factors. If relationships between certain variables are understood, adapted land management strategies can be developed. This study aims at linking pixel-level information with established remote sensing methods to the socio-economic concept of marginality based on household surveys and census data on administrative levels. Besides remote sensing and statistical analysis of socio-economic data a GIS is used for geospatial analysis. As most studies on land degradation focus on biophysical aspects such as vegetation or soil degradation this study uses an innovative approach by integrating biophysical analysis without neglecting a human oriented approach which plays a key role in environmental systems nowadays. This interdisciplinary research helps to get closer to the right and adapted policies and land management strategies as land degradation processes do not stick to administrative boundaries but policy advice does.

Graw, Valerie; Nkonya, Ephraim; Menz, Gunter

2014-05-01

361

Hispanic-serving land-grant colleges: Analysis and plan for an educational policy initiative  

Microsoft Academic Search

Hispanics and other minority Americans are denied access to higher education by a system that needs structural reform. The purpose of the research was to determine whether creating Hispanic-serving land-grant colleges, similar to the Morrill land-grant colleges serving Black and Native Americans, might be an effective strategy to increase the access of Hispanic students to quality higher education. In addition

Clifford Wayne Young

2001-01-01

362

23 CFR 972.208 - Federal lands pavement management system (PMS).  

Code of Federal Regulations, 2010 CFR

... Federal lands pavement management system (PMS). In addition...the AASHTO's “Pavement Management Guide.”2 2 “Pavement Management Guide,” AASHTO...the nature of the pavement network. These different...

2010-04-01

363

Design of an Automatic Landing System for the Meridian UAV using Fuzzy Logic  

E-print Network

This document describes the design of an automatic landing system for the Meridian unmanned aerial vehicle (UAV) in development for glacial ice research. The Center for Remote Sensing of Ice Sheets (CReSIS), established by the National Science...

Royer, David Andrew

2010-04-22

364

Mars science laboratory entry descent and landing system verification and validation program  

NASA Technical Reports Server (NTRS)

This paper discusses how system validation challenges influenced the design of the EDL architecture and highlights how some of the remaining challenges will be addressed to assure a successful landing of this unprecedented rover on Mars.

Mitcheltree, Robert; Steltzner, Adam; Chen, Allen; San Martin, Miguel; Rivellini, Tomasso

2006-01-01

365

Hydration of the lower stratosphere by ice crystal geysers over land convective systems  

E-print Network

The possible impact of deep convective overshooting over land has been explored by six simultaneous soundings of water vapour, particles and ozone in the lower stratosphere next to Mesoscale Convective Systems (MCSs) during ...

Khaykin, S.

366

Development of a satellite land and cloud data assimilation system coupled with WRF  

NASA Astrophysics Data System (ADS)

To obtain the satellite observations of cloud over the land and to assimilate them into the model are effective for rain prediction. However it cannot be easily achieved, because emissivity of clouds is weaker than that of land surface. In order to observe cloud over the land, we have to adequately represent the heterogeneity of land state, especially soil moisture distribution, which has large effect on emissivity of the land, and estimate the surface emissivity, then remove it as background information for cloud observation. For this purpose, we developed a satellite-based land and cloud data assimilation system coupled with the Weather Research and Forecasting Model (CALDAS-WRF), based on the Coupled Land and Atmosphere Data Assimilation System (CALDAS) (Rasmy et al. 2012). The CALDAS-WRF includes Simple Biosphere model version 2 (SiB2) as a land surface driver, radiative transfer models for surface soil layer and atmosphere as observation operators, and Ensemble Kalman Filter (EnKF) and 1DVAR as assimilation algorithms for land and cloud, respectively. The CALDAS-WRF first assimilates the soil moisture heterogeneity, using passive microwave brightness temperature (Tb) at lower frequency, which has a high sensitivity to soil moisture, and then assimilates cloud and water vapor, using Tb at higher frequency and optimized emissivity of land as a background information. To evaluate this system, the CALDAS-WRF was applied to a mesoscale region in the Tibetan Plateau. The experimental results show that the CALDAS-WRF effectively assimilated information of clouds contained in higher frequency microwave data and improved the representation of cloud distribution compared with satellite observation.

Seto, R.; Rasmy, M.; Koike, T.

2013-12-01

367

BATSE spectroscopy analysis system  

NASA Technical Reports Server (NTRS)

The Burst and Transient Source Experiment (BATSE) Spectroscopy Analysis System (BSAS) is the software system which is the primary tool for the analysis of spectral data from BATSE. As such, Guest Investigators and the community as a whole need to know its basic properties and characteristics. Described here are the characteristics of the BATSE spectroscopy detectors and the BSAS.

Schaefer, Bradley E.; Bansal, Sandhia; Basu, Anju; Brisco, Phil; Cline, Thomas L.; Friend, Elliott; Laubenthal, Nancy; Panduranga, E. S.; Parkar, Nuru; Rust, Brad

1992-01-01

368

Marine algae and land plants share conserved phytochrome signaling systems  

PubMed Central

Phytochrome photosensors control a vast gene network in streptophyte plants, acting as master regulators of diverse growth and developmental processes throughout the life cycle. In contrast with their absence in known chlorophyte algal genomes and most sequenced prasinophyte algal genomes, a phytochrome is found in Micromonas pusilla, a widely distributed marine picoprasinophyte (<2 µm cell diameter). Together with phytochromes identified from other prasinophyte lineages, we establish that prasinophyte and streptophyte phytochromes share core light-input and signaling-output domain architectures except for the loss of C-terminal response regulator receiver domains in the streptophyte phytochrome lineage. Phylogenetic reconstructions robustly support the presence of phytochrome in the common progenitor of green algae and land plants. These analyses reveal a monophyletic clade containing streptophyte, prasinophyte, cryptophyte, and glaucophyte phytochromes implying an origin in the eukaryotic ancestor of the Archaeplastida. Transcriptomic measurements reveal diurnal regulation of phytochrome and bilin chromophore biosynthetic genes in Micromonas. Expression of these genes precedes both light-mediated phytochrome redistribution from the cytoplasm to the nucleus and increased expression of photosynthesis-associated genes. Prasinophyte phytochromes perceive wavelengths of light transmitted farther through seawater than the red/far-red light sensed by land plant phytochromes. Prasinophyte phytochromes also retain light-regulated histidine kinase activity lost in the streptophyte phytochrome lineage. Our studies demonstrate that light-mediated nuclear translocation of phytochrome predates the emergence of land plants and likely represents a widespread signaling mechanism in unicellular algae. PMID:25267653

Duanmu, Deqiang; Bachy, Charles; Sudek, Sebastian; Wong, Chee-Hong; Jimenez, Valeria; Rockwell, Nathan C.; Martin, Shelley S.; Ngan, Chew Yee; Reistetter, Emily N.; van Baren, Marijke J.; Price, Dana C.; Wei, Chia-Lin; Reyes-Prieto, Adrian; Lagarias, J. Clark; Worden, Alexandra Z.

2014-01-01

369

Marine algae and land plants share conserved phytochrome signaling systems.  

PubMed

Phytochrome photosensors control a vast gene network in streptophyte plants, acting as master regulators of diverse growth and developmental processes throughout the life cycle. In contrast with their absence in known chlorophyte algal genomes and most sequenced prasinophyte algal genomes, a phytochrome is found in Micromonas pusilla, a widely distributed marine picoprasinophyte (<2 µm cell diameter). Together with phytochromes identified from other prasinophyte lineages, we establish that prasinophyte and streptophyte phytochromes share core light-input and signaling-output domain architectures except for the loss of C-terminal response regulator receiver domains in the streptophyte phytochrome lineage. Phylogenetic reconstructions robustly support the presence of phytochrome in the common progenitor of green algae and land plants. These analyses reveal a monophyletic clade containing streptophyte, prasinophyte, cryptophyte, and glaucophyte phytochromes implying an origin in the eukaryotic ancestor of the Archaeplastida. Transcriptomic measurements reveal diurnal regulation of phytochrome and bilin chromophore biosynthetic genes in Micromonas. Expression of these genes precedes both light-mediated phytochrome redistribution from the cytoplasm to the nucleus and increased expression of photosynthesis-associated genes. Prasinophyte phytochromes perceive wavelengths of light transmitted farther through seawater than the red/far-red light sensed by land plant phytochromes. Prasinophyte phytochromes also retain light-regulated histidine kinase activity lost in the streptophyte phytochrome lineage. Our studies demonstrate that light-mediated nuclear translocation of phytochrome predates the emergence of land plants and likely represents a widespread signaling mechanism in unicellular algae. PMID:25267653

Duanmu, Deqiang; Bachy, Charles; Sudek, Sebastian; Wong, Chee-Hong; Jiménez, Valeria; Rockwell, Nathan C; Martin, Shelley S; Ngan, Chew Yee; Reistetter, Emily N; van Baren, Marijke J; Price, Dana C; Wei, Chia-Lin; Reyes-Prieto, Adrian; Lagarias, J Clark; Worden, Alexandra Z

2014-11-01

370

Capturing interactions between nitrogen and hydrological cycles under historical climate and land use: Susquehanna watershed analysis with the GFDL land model LM3-TAN  

NASA Astrophysics Data System (ADS)

We developed a process model LM3-TAN to assess the combined effects of direct human influences and climate change on terrestrial and aquatic nitrogen (TAN) cycling. The model was developed by expanding NOAA's Geophysical Fluid Dynamics Laboratory land model LM3V-N of coupled terrestrial carbon and nitrogen (C-N) cycling and including new N cycling processes and inputs such as a soil denitrification, point N sources to streams (i.e., sewage), and stream transport and microbial processes. Because the model integrates ecological, hydrological, and biogeochemical processes, it captures key controls of the transport and fate of N in the vegetation-soil-river system in a comprehensive and consistent framework which is responsive to climatic variations and land-use changes. We applied the model at 1/8° resolution for a study of the Susquehanna River Basin. We simulated with LM3-TAN stream dissolved organic-N, ammonium-N, and nitrate-N loads throughout the river network, and we evaluated the modeled loads for 1986-2005 using data from 16 monitoring stations as well as a reported budget for the entire basin. By accounting for interannual hydrologic variability, the model was able to capture interannual variations of stream N loadings. While the model was calibrated with the stream N loads only at the last downstream Susquehanna River Basin Commission station Marietta (40°02' N, 76°32' W), it captured the N loads well at multiple locations within the basin with different climate regimes, land-use types, and associated N sources and transformations in the sub-basins. Furthermore, the calculated and previously reported N budgets agreed well at the level of the whole Susquehanna watershed. Here we illustrate how point and non-point N sources contributing to the various ecosystems are stored, lost, and exported via the river. Local analysis of six sub-basins showed combined effects of land use and climate on soil denitrification rates, with the highest rates in the Lower Susquehanna Sub-Basin (extensive agriculture; Atlantic coastal climate) and the lowest rates in the West Branch Susquehanna Sub-Basin (mostly forest; Great Lakes and Midwest climate). In the re-growing secondary forests, most of the N from non-point sources was stored in the vegetation and soil, but in the agricultural lands most N inputs were removed by soil denitrification, indicating that anthropogenic N applications could drive substantial increase of N2O emission, an intermediate of the denitrification process.

Lee, M.; Malyshev, S.; Shevliakova, E.; Milly, P. C. D.; Jaffé, P. R.

2014-10-01

371

Capturing interactions between nitrogen and hydrological cycles under historical climate and land use: Susquehanna watershed analysis with the GFDL land model LM3-TAN  

USGS Publications Warehouse

We developed a process model LM3-TAN to assess the combined effects of direct human influences and climate change on terrestrial and aquatic nitrogen (TAN) cycling. The model was developed by expanding NOAA's Geophysical Fluid Dynamics Laboratory land model LM3V-N of coupled terrestrial carbon and nitrogen (C-N) cycling and including new N cycling processes and inputs such as a soil denitrification, point N sources to streams (i.e., sewage), and stream transport and microbial processes. Because the model integrates ecological, hydrological, and biogeochemical processes, it captures key controls of the transport and fate of N in the vegetation–soil–river system in a comprehensive and consistent framework which is responsive to climatic variations and land-use changes. We applied the model at 1/8° resolution for a study of the Susquehanna River Basin. We simulated with LM3-TAN stream dissolved organic-N, ammonium-N, and nitrate-N loads throughout the river network, and we evaluated the modeled loads for 1986–2005 using data from 16 monitoring stations as well as a reported budget for the entire basin. By accounting for interannual hydrologic variability, the model was able to capture interannual variations of stream N loadings. While the model was calibrated with the stream N loads only at the last downstream Susquehanna River Basin Commission station Marietta (40°02' N, 76°32' W), it captured the N loads well at multiple locations within the basin with different climate regimes, land-use types, and associated N sources and transformations in the sub-basins. Furthermore, the calculated and previously reported N budgets agreed well at the level of the whole Susquehanna watershed. Here we illustrate how point and non-point N sources contributing to the various ecosystems are stored, lost, and exported via the river. Local analysis of six sub-basins showed combined effects of land use and climate on soil denitrification rates, with the highest rates in the Lower Susquehanna Sub-Basin (extensive agriculture; Atlantic coastal climate) and the lowest rates in the West Branch Susquehanna Sub-Basin (mostly forest; Great Lakes and Midwest climate). In the re-growing secondary forests, most of the N from non-point sources was stored in the vegetation and soil, but in the agricultural lands most N inputs were removed by soil denitrification, indicating that anthropogenic N applications could drive substantial increase of N2O emission, an intermediate of the denitrification process.

Lee, M.; Malyshev, S.; Shevliakova, E.; Milly, Paul C. D.; Jaffé, P. R.

2014-01-01

372

. Tension Infiltration for Estimating Pore Distribution of Alfisols under Different Land Management Systems  

Microsoft Academic Search

A field infiltration study was undertaken to evaluate near-surface pore characteristics under long-term land management systems in the semi-arid tropical Alfisols of India. Double ring and tension infiltrometer methods using tension equivalent to 3, 6 and 15 em of water column were applied to soil under four land use systems; viz. cultivated field, under sorghum (Sorghum bicolor (L.)-castor (Ricinus communis

UTTAM KUMAR MANDAL; V. RAMESH; K. L. SHARMA; KAUSALYA RAMACHANDRAN

373

Decision-support systems for natural-hazards and land-management issues  

USGS Publications Warehouse

Scientists at the USGS Western Geographic Science Center are developing decision-support systems (DSSs) for natural-hazards and land-management issues. DSSs are interactive computer-based tools that use data and models to help identify and solve problems. These systems can provide crucial support to policymakers, planners, and communities for making better decisions about long-term natural hazards mitigation and land-use planning.

Dinitz, Laura; Forney, William; Byrd, Kristin

2012-01-01

374

Inertial navigation systems analysis.  

NASA Technical Reports Server (NTRS)

This volume offers the avionic systems engineer a fundamental exposition of the mechanization and error analysis of inertial navigation systems. While the material is applicable to spacecraft and undersea navigation, emphasis is placed upon terrestrial applications on or slightly above the earth's surface. As a result, practical considerations are geared toward those aircraft navigation systems of particular current interest. Extensive use is made of perturbation techniques to develop linearized system equations, whose solutions closely approximate those obtained by nonlinear differential equations. A unified error analysis technique is developed that is applicable to virtually all system configurations. The technique provides a greatly simplified method for comparing the performance of competing system configurations.

Britting, K. R.

1971-01-01

375

INTEGRATED LAND-USE SYSTEMS: ASSESSMENT OF PROMISING AGROFOREST AND ALTERNATIVE LAND-USE PRACTICES TO ENHANCE CARBON CONSERVATION AND SEQUESTRATION  

EPA Science Inventory

Degraded or sub-standard soils and marginal lands occupy a significant proportion of boreal, temperate and tropical biomes. anagement of these lands with a wide range of existing, site-specific, integrated, agroforest systems represents a significant global opportunity to reduce ...

376

Relations Among Geology, Physiography, Land Use, and Stream Habitat Conditions in the Buffalo and Current River Systems, Missouri and Arkansas  

USGS Publications Warehouse

This study investigated links between drainage-basin characteristics and stream habitat conditions in the Buffalo National River, Arkansas and the Ozark National Scenic Riverways, Missouri. It was designed as an associative study - the two parks were divided into their principle tributary drainage basins and then basin-scale and stream-habitat data sets were gathered and compared between them. Analyses explored the relative influence of different drainage-basin characteristics on stream habitat conditions. They also investigated whether a relation between land use and stream characteristics could be detected after accounting for geologic and physiographic differences among drainage basins. Data were collected for three spatial scales: tributary drainage basins, tributary stream reaches, and main-stem river segments of the Current and Buffalo Rivers. Tributary drainage-basin characteristics were inventoried using a Geographic Information System (GIS) and included aspects of drainage-basin physiography, geology, and land use. Reach-scale habitat surveys measured channel longitudinal and cross-sectional geometry, substrate particle size and embeddedness, and indicators of channel stability. Segment-scale aerial-photo based inventories measured gravel-bar area, an indicator of coarse sediment load, along main-stem rivers. Relations within and among data sets from each spatial scale were investigated using correlation analysis and multiple linear regression. Study basins encompassed physiographically distinct regions of the Ozarks. The Buffalo River system drains parts of the sandstone-dominated Boston Mountains and of the carbonate-dominated Springfield and Salem Plateaus. The Current River system is within the Salem Plateau. Analyses of drainage-basin variables highlighted the importance of these physiographic differences and demonstrated links among geology, physiography, and land-use patterns. Buffalo River tributaries have greater relief, steeper slopes, and more streamside bluffs than the Current River tributaries. Land use patterns in both river systems correlate with physiography - cleared land area is negatively associated with drainage-basin average slope. Both river systems are dominantly forested (0-35 per-cent cleared land), however, the potential for landscape disturbance may be greater in the Buffalo River system where a larger proportion of cleared land occurs on steep slopes (>15 degrees). When all drainage basins are grouped together, reach-scale channel characteristics show the strongest relations with drainage-basin physiography. Bankfull channel geometry and residual pool dimensions are positively correlated with drainage area and topographic relief variables. After accounting for differences in drainage area, channel dimensions in Buffalo River tributaries tend to be larger than in Current River tributaries. This trend is consistent with the flashy runoff and large storm flows that can be generated in rugged, sandstone-dominate terrain. Substrate particle size is also most strongly associated with physiography; particle size is positively correlated with topographic relief variables. When tributaries are subset by river system, relations with geology and land use variables become apparent. Buffalo River tributaries with larger proportions of carbonate bedrock and cleared land area have shallower channels, better-sorted, gravel-rich substrate, and more eroding banks than those with little cleared land and abundant sandstone bedrock. Gravel-bar area on the Buffalo River main stem was also larger within 1-km of carbonate-rich tributary junctions. Because geology and cleared land are themselves correlated, relations with anthropogenic and natural factors could often not be separated. Channel characteristics in the Current River system show stronger associations with physiography than with land use. Channels are shallower and have finer substrates in the less rugged, karst-rich, western basins than in the

Panfil, Maria S.; Jacobson, Robert B.

2001-01-01

377

Urban land use of the Sao Paulo metropolitan area by automatic analysis of LANDSAT data  

NASA Technical Reports Server (NTRS)

The separability of urban land use classes in the metropolitan area of Sao Paulo was studied by means of automatic analysis of MSS/LANDSAT digital data. The data were analyzed using the media K and MAXVER classification algorithms. The land use classes obtained were: CBD/vertical growth area, residential area, mixed area, industrial area, embankment area type 1, embankment area type 2, dense vegetation area and sparse vegetation area. The spectral analysis of representative samples of urban land use classes was done using the "Single Cell" analysis option. The classes CBD/vertical growth area, residential area and embankment area type 2 showed better spectral separability when compared to the other classes.

Parada, N. D. J. (principal investigator); Niero, M.; Foresti, C.

1983-01-01

378

WORLD-SYSTEMS ANALYSIS  

Microsoft Academic Search

Summary World-systems analysis is a knowledge movement elaborated since the 1970's and is a critique of dominant modes of analysis in the nineteenth-century social sciences. It insists on three things primarily: (1) World-systems (and not nation-states) are the basic unit of social analysis; (2) Neither nomothetic nor idiographic epistemologies permit useful analyses of social reality; (3) The existing disciplinary boundaries

Immanuel Wallerstein

1970-01-01

379

Simulating the conversion of rural settlements to town land based on multi-agent systems and cellular automata.  

PubMed

Rapid urbanization in China has triggered the conversion of land from rural to urban use, particularly the conversion of rural settlements to town land. This conversion is the result of the joint effects of the geographic environment and agents involving the government, investors, and farmers. To understand the dynamic interaction dominated by agents and to predict the future landscape of town expansion, a small town land-planning model is proposed based on the integration of multi-agent systems (MAS) and cellular automata (CA). The MAS-CA model links the decision-making behaviors of agents with the neighbor effect of CA. The interaction rules are projected by analyzing the preference conflicts among agents. To better illustrate the effects of the geographic environment, neighborhood, and agent behavior, a comparative analysis between the CA and MAS-CA models in three different towns is presented, revealing interesting patterns in terms of quantity, spatial characteristics, and the coordinating process. The simulation of rural settlements conversion to town land through modeling agent decision and human-environment interaction is very useful for understanding the mechanisms of rural-urban land-use change in developing countries. This process can assist town planners in formulating appropriate development plans. PMID:24244472

Liu, Yaolin; Kong, Xuesong; Liu, Yanfang; Chen, Yiyun

2013-01-01

380

Simulating the Conversion of Rural Settlements to Town Land Based on Multi-Agent Systems and Cellular Automata  

PubMed Central

Rapid urbanization in China has triggered the conversion of land from rural to urban use, particularly the conversion of rural settlements to town land. This conversion is the result of the joint effects of the geographic environment and agents involving the government, investors, and farmers. To understand the dynamic interaction dominated by agents and to predict the future landscape of town expansion, a small town land-planning model is proposed based on the integration of multi-agent systems (MAS) and cellular automata (CA). The MAS-CA model links the decision-making behaviors of agents with the neighbor effect of CA. The interaction rules are projected by analyzing the preference conflicts among agents. To better illustrate the effects of the geographic environment, neighborhood, and agent behavior, a comparative analysis between the CA and MAS-CA models in three different towns is presented, revealing interesting patterns in terms of quantity, spatial characteristics, and the coordinating process. The simulation of rural settlements conversion to town land through modeling agent decision and human-environment interaction is very useful for understanding the mechanisms of rural-urban land-use change in developing countries. This process can assist town planners in formulating appropriate development plans. PMID:24244472

Liu, Yaolin; Kong, Xuesong; Liu, Yanfang; Chen, Yiyun

2013-01-01

381

Miltipath measurements for land mobile satellite service using global positioning system signals  

NASA Technical Reports Server (NTRS)

A proposed multipath system for the land mobile satellite radio channel using the Global Positioning System (GPS) is presented. The measurement technique and equipment used to make multipath measurements on communications links are briefly described. The system configuration and performance specifications of the proposed measurement system are discussed.

Lemmon, John J.

1988-01-01

382

Towards a public, standardized, diagnostic benchmarking system for land surface models  

NASA Astrophysics Data System (ADS)

We examine different conceptions of land surface model benchmarking and illustrate the importance of internationally standardized evaluation experiments that specify data sets, variables, metrics and model resolutions. We additionally show how essential the definition of a priori expectations of model performance can be, based on the complexity of a model and the amount of information being provided to it, and give an example of how these expectations might be quantified. Finally, we introduce the Protocol for the Analysis of Land Surface models (PALS), a free, online land surface model benchmarking application, and show how it is structured to meet both of these goals.

Abramowitz, G.

2012-02-01

383

Towards a public, standardized, diagnostic benchmarking system for land surface models  

NASA Astrophysics Data System (ADS)

This work examines different conceptions of land surface model benchmarking and the importance of internationally standardized evaluation experiments that specify data sets, variables, metrics and model resolutions. It additionally demonstrates how essential the definition of a priori expectations of model performance can be, based on the complexity of a model and the amount of information being provided to it, and gives an example of how these expectations might be quantified. Finally, the Protocol for the Analysis of Land Surface models (PALS) is introduced - a free, online land surface model benchmarking application that is structured to meet both of these goals.

Abramowitz, G.

2012-06-01

384

Tracing the source and fate of nitrate in contemporary mixed land-use surface water systems  

NASA Astrophysics Data System (ADS)

Nitrogenous fertilizers increase agricultural productivity, ultimately feeding the planet. Yet, it is possible to have too much of a good thing, and nitrogen is no exception. When in excess nitrogen has been shown to accelerate eutrophication of water bodies, and act as a chronic toxin (e.g. methemoglobinemia). As land-use intensity continues to rise in response to increases in agricultural productivity, the risk of adverse effects of nitrogen loading on surface water bodies will also increase. Stable isotope proxies are potential tracers of nitrate, the most common nitrogenous phase in surface waters. Applying stable isotope proxies therefore presents an opportunity to identify and manage sources of excess nitrogen before aquatic systems are severely degraded. However, the heterogeneous nature of potential pollution sources themselves, and their distribution with a modified catchment network, make understanding this issue highly complex. The Banks Peninsula, an eroded late tertiary volcanic complex located on the east coast of the South Island New Zealand, presents a unique opportunity to study and understand the sources and fates of nitrate within streams in a contemporary mixed land-use setting. Within this small geographic area there a variety of agricultural activities are practiced, including: heavily fertilized golf courses; stands of regenerating native forest; and areas of fallow gorse (Ulex europaeus; a invasive N-fixing shrub). Each of these landuse classes has its own unique nitrogen budget. Multivariate analysis was used on stream nitrate concentrations to reveal that stream reaches dominated by gorse had significantly higher nitrate concentrations than other land-use classes. Nitrate ?15N & ?18O data from these sites show strong covariance, plotting along a distinct fractionation line (r2 = 0.96). This finding facilitates interpretation of what processes are controlling nitrate concentration within these systems. Further, complementary aquatic foodweb ?15N ?13C analyses of multiple species in various trophic positions allow for a unique, holistic insight in to the fate of gorse-derived nitrate at an ecosystem level. We present here physicochemical and stable isotopic data from a variety of aqueous and aquatic foodweb components. Data is generated using emerging and established analytical techniques, in order to explore links between foodweb ecology, ecosystem function, and fate and transport of excess nitrate along longitudinal gradients of mixed land-use catchments.

Stewart, S. D.; Young, M. B.; Horton, T. W.; Harding, J. S.

2011-12-01

385

Infrastructure analysis system (IAS)  

Microsoft Academic Search

The Senior Policy Group, advisors to managers of the National Capital Region (DC, MD, VA) needs a decision aid tool to help in appropriating critical infrastructure protection funds. The proposed system is designed to work with data from energy, water, and healthcare sectors. The system addresses the combined problem of network degradation, and analysis. The system will also provide planning

Y. M. Ashparie; Oluwaseyi Pius Bashorun; Greg Joseph Koch; G. R. Siegel; Petko Traoumir Stoyanov

2005-01-01

386

The Met Office Coupled Atmosphere/Land/Ocean/Sea-Ice Data Assimilation System  

NASA Astrophysics Data System (ADS)

The Met Office has developed a weakly-coupled data assimilation (DA) system using the global coupled model HADGEM3 (Hadley Centre Global Environment Model, version 3). This model combines the atmospheric model UM (Unified Model) at 60 km horizontal resolution on 85 vertical levels, the ocean model NEMO (Nucleus for European Modeling of the Ocean) at 25 km (at the equator) horizontal resolution on 75 vertical levels, and the sea-ice model CICE at the same resolution as NEMO. The atmosphere and the ocean/sea-ice fields are coupled every 1-hour using the OASIS coupler. The coupled model is corrected using two separate 6-hour window data assimilation systems: a 4D-Var for the atmosphere with associated soil moisture content nudging and snow analysis schemes on the one hand, and a 3D-Var FGAT for the ocean and sea-ice on the other hand. The background information in the DA systems comes from a previous 6-hour forecast of the coupled model. To show the impact of coupled DA, one-month experiments have been carried out, including 1) a full atmosphere/land/ocean/sea-ice coupled DA run, 2) an atmosphere-only run forced by OSTIA SSTs and sea-ice with atmosphere and land DA, and 3) an ocean-only run forced by atmospheric fields from run 2 with ocean and sea-ice DA. In addition, 5-day forecast runs, started twice a day, have been produced from initial conditions generated by either run 1 or a combination of runs 2 and 3. The different results have been compared to each other and, whenever possible, to other references such as the Met Office atmosphere and ocean operational analyses or the OSTIA data. These all show the coupled DA system functioning well. Evidence of imbalances and initialisation shocks has also been looked for.

Lea, Daniel; Mirouze, Isabelle; Martin, Matthew; Hines, Adrian; Guiavarch, Catherine; Shelly, Ann

2014-05-01

387

Modeling the Behaviour of an Advanced Material Based Smart Landing Gear System for Aerospace Vehicles  

NASA Astrophysics Data System (ADS)

The last two decades have seen a substantial rise in the use of advanced materials such as polymer composites for aerospace structural applications. In more recent years there has been a concerted effort to integrate materials, which mimic biological functions (referred to as smart materials) with polymeric composites. Prominent among smart materials are shape memory alloys, which possess both actuating and sensory functions that can be realized simultaneously. The proper characterization and modeling of advanced and smart materials holds the key to the design and development of efficient smart devices/systems. This paper focuses on the material characterization; modeling and validation of the model in relation to the development of a Shape Memory Alloy (SMA) based smart landing gear (with high energy dissipation features) for a semi rigid radio controlled airship (RC-blimp). The Super Elastic (SE) SMA element is configured in such a way that it is forced into a tensile mode of high elastic deformation. The smart landing gear comprises of a landing beam, an arch and a super elastic Nickel-Titanium (Ni-Ti) SMA element. The landing gear is primarily made of polymer carbon composites, which possess high specific stiffness and high specific strength compared to conventional materials, and are therefore ideally suited for the design and development of an efficient skid landing gear system with good energy dissipation characteristics. The development of the smart landing gear in relation to a conventional metal landing gear design is also dealt with.

Varughese, Byji; Dayananda, G. N.; Rao, M. Subba

2008-07-01

388

Modeling the Behaviour of an Advanced Material Based Smart Landing Gear System for Aerospace Vehicles  

SciTech Connect

The last two decades have seen a substantial rise in the use of advanced materials such as polymer composites for aerospace structural applications. In more recent years there has been a concerted effort to integrate materials, which mimic biological functions (referred to as smart materials) with polymeric composites. Prominent among smart materials are shape memory alloys, which possess both actuating and sensory functions that can be realized simultaneously. The proper characterization and modeling of advanced and smart materials holds the key to the design and development of efficient smart devices/systems. This paper focuses on the material characterization; modeling and validation of the model in relation to the development of a Shape Memory Alloy (SMA) based smart landing gear (with high energy dissipation features) for a semi rigid radio controlled airship (RC-blimp). The Super Elastic (SE) SMA element is configured in such a way that it is forced into a tensile mode of high elastic deformation. The smart landing gear comprises of a landing beam, an arch and a super elastic Nickel-Titanium (Ni-Ti) SMA element. The landing gear is primarily made of polymer carbon composites, which possess high specific stiffness and high specific strength compared to conventional materials, and are therefore ideally suited for the design and development of an efficient skid landing gear system with good energy dissipation characteristics. The development of the smart landing gear in relation to a conventional metal landing gear design is also dealt with.

Varughese, Byji; Dayananda, G. N.; Rao, M. Subba [National Aerospace Laboratories, P.B. No: 1779, Airport Road, Bangalore-560017 (India)

2008-07-29

389

Watershed scale environmental sustainability analysis of biofuel production in changing land use and climate scenarios  

NASA Astrophysics Data System (ADS)

One of the grand challenges in meeting the US biofuel goal is producing large quantities of cellulosic biofeedstock materials for the production of biofuels in an environmentally sustainable and economically viable manner. The possible land use and land management practice changes induce concerns over the environmental impacts of these bioenergy crop production scenarios both in terms of water availability and water quality, and these impacts may be exacerbated by climate variability and change. This study aims to evaluate environmental sustainability of various plausible land and crop management scenarios for biofuel production under changing climate scenarios for a Midwest US watershed. The study considers twelve environmental sustainability indicators related hydrology and water quality with thirteen plausible biofuels scenarios in the watershed under nine climate change scenarios. The land use change scenarios for evaluation includes, (1) bioenergy crops in highly erodible soils (3) bioenergy crops in low row crop productive fields (marginal lands); (3) bioenergy crops in pasture and range land use areas and (4) combinations of these scenarios. Future climate data bias corrected and downscaled to daily values from the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset were used in this study. The distributed hydrological model SWAT (Soil and Water Assessment Tool) was used to simulate bioenergy crops growth, hydrology and water quality. The watershed scale sustainability analysis was done in Wildcat Creek basin, which is located in North-Central Indiana, USA.

RAJ, C.; Chaubey, I.; Cherkauer, K. A.; Brouder, S. M.; Volenec, J. J.

2013-12-01

390

Entry, Descent, and Landing Operations Analysis for the Stardust Entry Capsule  

NASA Technical Reports Server (NTRS)

On the morning of January 15, 2006, the Stardust capsule successfully landed at the Utah Test and Training range in northwest Utah returning cometary samples from the comet Wild-2. An overview of the entry, descent, and landing (EDL) trajectory analysis that was performed for targeting during the mission operations phase upon final approach to Earth is described. The final orbit determination solution produced an inertial entry flight-path angle of -8.21 deg (the desired nominal value) with a 3-sigma uncertainty of +/-0.0017 deg (2% of the requirement). The navigation and EDL operations effort accurately delivered the entry capsule to the desired landing site. The final landing location was 8.1 km from the target, which was well within the allowable landing area. Overall, the Earth approach operation procedures worked well and there were no issues (logistically or performance based) that arose. As a result, the process of targeting a capsule from an interplanetary trajectory and accurately landing it on Earth was successfully demonstrated.

Desai, Prasun N.; Lyons, Dan T.; Tooley, Jeff; Kangas, Julie

2008-01-01

391

Integration of Data Assimilation, Stochastic Optimization and Uncertainty Modeling within NASA's Land Information System (LIS)  

NASA Astrophysics Data System (ADS)

Recent advances in information systems technology have significantly improved our ability to fully exploit the information content of remote sensing data. In this talk, we discuss a range of applications for the optimization and uncertainty tools recently incorporated into the NASA Land Information System (LIS) to address this challenge. LIS is a high-resolution, high-performance, land surface modeling and data assimilation system that supports a wide range of land surface research and applications. The applications of the new optimization and uncertainty tools involve several LIS land-coupled models, including the Weather Research and Forecasting Model (WRF), models of land microwave emission (the Soil Moisture and Ocean Salinity (SMOS) Community Microwave Emission Model (CMEM)), radiative transfer (Joint Center for Satellite Data Assimilation's Community Radiative Transfer Model (CRTM)), landslide and streamflow simulation. The impact of parameter estimation on land surface modeling is investigated for a range of studies, including soil moisture modeling in the Walnut Gulch experimental watershed, land data assimilation over the continental United States, and coupled land-atmosphere forecasts using WRF for the Southern Great Plains. In addition, the uncertainty in the outputs of such coupled systems is investigated. The uncertainty methods include Monte Carlo for propagating parameter uncertainties and model errors as well as Markov chain Monte Carlo methods that enable the updating of parameter uncertainties with remote sensing data. The tradeoffs between uncertainty estimation and parameter estimation are also highlighted. Finally, remaining challenges for the development of information systems of this kind are identified, including challenges in their use as part of mission simulation experiments.

Harrison, K.; Peters-Lidard, C. D.; Kumar, S.; Santanello, J. A.; Kirschbaum, D. B.

2011-12-01

392

Forcing a Global, Offline Land Surface Modeling System with Observation-Based Fields  

NASA Technical Reports Server (NTRS)

The Global Land Data Assimilation System (GLDAS) drives multiple uncoupled land surface models in order to produce optimal output fields of surface states in near-real time, globally, at 1/4 degree spatial resolution. These fields are then made available for coupled atmospheric model initialization and further research. One of the unique aspects of GLDAS is its ability to ingest both modeled and observation-derived forcing for running global scale land surface models. This paper compares results of runs forced by modeled and observed precipitation and shortwave radiation fields. Differences are examined and the impact of the observations on model skill is assessed.

Rodell, Matthew; Houser, Paul R.; Jambor, U.; Gottschalck, J.; Radakovich, J.; Arsenault, K.; Meng, C.-J.; Mitchell, K. E.

2002-01-01

393

Land-use poverty traps identified in shifting cultivation systems shape long-term tropical forest cover.  

PubMed

In this article we illustrate how fine-grained longitudinal analyses of land holding and land use among forest peasant households in an Amazonian village can enrich our understanding of the poverty/land cover nexus. We examine the dynamic links in shifting cultivation systems among asset poverty, land use, and land cover in a community where poverty is persistent and primary forests have been replaced over time--with community enclosure--by secondary forests (i.e., fallows), orchards, and crop land. Land cover change is assessed using aerial photographs/satellite imagery from 1965 to 2007. Household and plot level data are used to track land holding, portfolios, and use as well as land cover over the past 30 y, with particular attention to forest status (type and age). Our analyses find evidence for two important types of "land-use" poverty traps--a "subsistence crop" trap and a "short fallow" trap--and indicate that the initial conditions of land holding by forest peasants have long-term effects on future forest cover and household welfare. These findings suggest a new mechanism driving poverty traps: insufficient initial land holdings induce land use patterns that trap households in low agricultural productivity. Path dependency in the evolution of household land portfolios and land use strategies strongly influences not only the wellbeing of forest people but also the dynamics of tropical deforestation and secondary forest regrowth. PMID:21873179

Coomes, Oliver T; Takasaki, Yoshito; Rhemtulla, Jeanine M

2011-08-23

394

Semi-active control of a landing gear system using magnetrorheological damper  

NASA Astrophysics Data System (ADS)

This paper is concerned with the applicability of the developed MR damper to the landing gear system for the attenuating undesired shock and vibration in the landing and taxing phases. First of all, the experimental model of the MR damper is derived based on the results of performance evaluations. Next, a simplified skyhook controller, which is one of the most straightforward, but effective approaches for improving ride comport in vehicles with active suspensions, is formulated. Finally, the vibration control performances of the landing gear system using the MR damper are theoretically evaluated in the landing phase of the aircraft. A series of simulation analyses show that the proposed MR damper with the skyhook controller is effective for suppressing undesired vibration of the aircraft body.

Nam, Y. J.; Park, M. K.; Choi, J. W.; Yamane, R.

2007-12-01

395

Covariance Analysis Tool (G-CAT) for Computing Ascent, Descent, and Landing Errors  

NASA Technical Reports Server (NTRS)

G-CAT is a covariance analysis tool that enables fast and accurate computation of error ellipses for descent, landing, ascent, and rendezvous scenarios, and quantifies knowledge error contributions needed for error budgeting purposes. Because GCAT supports hardware/system trade studies in spacecraft and mission design, it is useful in both early and late mission/ proposal phases where Monte Carlo simulation capability is not mature, Monte Carlo simulation takes too long to run, and/or there is a need to perform multiple parametric system design trades that would require an unwieldy number of Monte Carlo runs. G-CAT is formulated as a variable-order square-root linearized Kalman filter (LKF), typically using over 120 filter states. An important property of G-CAT is that it is based on a 6-DOF (degrees of freedom) formulation that completely captures the combined effects of both attitude and translation errors on the propagated trajectories. This ensures its accuracy for guidance, navigation, and control (GN&C) analysis. G-CAT provides the desired fast turnaround analysis needed for error budgeting in support of mission concept formulations, design trade studies, and proposal development efforts. The main usefulness of a covariance analysis tool such as G-CAT is its ability to calculate the performance envelope directly from a single run. This is in sharp contrast to running thousands of simulations to obtain similar information using Monte Carlo methods. It does this by propagating the "statistics" of the overall design, rather than simulating individual trajectories. G-CAT supports applications to lunar, planetary, and small body missions. It characterizes onboard knowledge propagation errors associated with inertial measurement unit (IMU) errors (gyro and accelerometer), gravity errors/dispersions (spherical harmonics, masscons), and radar errors (multiple altimeter beams, multiple Doppler velocimeter beams). G-CAT is a standalone MATLAB- based tool intended to run on any engineer's desktop computer.

Boussalis, Dhemetrios; Bayard, David S.

2013-01-01

396

Georelational analysis of soil type, soil salt content, landform, and land use in the Yellow River Delta, China.  

PubMed

The Yellow River Delta, one of China's three major river deltas, is becoming a major region for the development of agriculture and fisheries. Protecting the delicate ecology of newly formed aquatic systems as well as the evolution of soils, natural vegetation, and fauna on older upland environments in the delta is a priority in planning for the wise use of the delta's resources for future agricultural development. In this article, we use a Geographic Information System (GIS) to analyze relationships between land-use/ land-cover characteristics in the Dongying municipality, one of the most intensely developed areas of the delta, and spatial variations in soil salinity and landforms. This analysis reveals that soil salt content decreases from regionally high values in isolated depressions to relatively moderate values in embanked former back swamps, with the lowest values occurring in abandoned river courses. Comparing the present land use on this soil salinity-landform pattern shows that it is basically at odds with general concepts of land suitability for agricultural utilization of saline soils. Crop-based agriculture in the region is probably overdeveloped, whereas more appropriate agricultural development, like cattle and forest production, is underrepresented. Future development should focus on converting farmland in embanked former back swamps and abandoned river courses into grasslands and forests. Crop-based agriculture (up to 151,000 ha) could be planned at the low-salinity terrace uplands and flood plains. The article provides guidelines for decision-makers regarding agricultural land use and wetland protection in the Yellow River Delta. PMID:15984065

Fang, Hongliang; Liu, Gaohuan; Kearney, Michael

2005-01-01

397

Parameter uncertainty analysis of non-point source pollution from different land use types.  

PubMed

Land use type is one of the most important factors that affect the uncertainty in non-point source (NPS) pollution simulation. In this study, seventeen sensitive parameters were screened from the Soil and Water Assessment Tool (SWAT) model for parameter uncertainty analysis for different land use types in the Daning River Watershed of the Three Gorges Reservoir area, China. First-Order Error Analysis (FOEA) method was adopted to analyze the effect of parameter uncertainty on model outputs under three types of land use, namely, plantation, forest and grassland. The model outputs selected in this study consisted of runoff, sediment yield, organic nitrogen (N), and total phosphorus (TP). The results indicated that the uncertainty conferred by the parameters differed among the three land use types. In forest and grassland, the parameter uncertainty in NPS pollution was primarily associated with runoff processes, but in plantation, the main uncertain parameters were related to runoff process and soil properties. Taken together, the study suggested that adjusting the structure of land use and controlling fertilizer use are helpful methods to control the NPS pollution in the Daning River Watershed. PMID:20035971

Shen, Zhen-yao; Hong, Qian; Yu, Hong; Niu, Jun-feng

2010-03-15

398

Land classification and change intensity analysis in a coastal watershed of Southeast China.  

PubMed

The aim of this study is to improve the understanding of land changes in the Jiulong River watershed, a coastal watershed of Southeast China. We developed a stratified classification methodology for land mapping, which combines linear stretching, an Iterative Self-Organizing Data Analysis (ISODATA) clustering algorithm, and spatial reclassification. The stratified classification for 2002 generated less overall error than an unstratified classification. The stratified classifications were then used to examine temporal differences at 1986, 1996, 2002, 2007 and 2010. Intensity Analysis was applied to analyze land changes at three levels: time interval, category, and transition. Results showed that land use transformation has been accelerating. Woodland's gains and losses were dormant while the gains and losses of Agriculture, Orchard, Built-up and Bare land were active during all time intervals. Water's losses were active and stationary. The transitions from Agriculture, Orchard, and Water to Built-up were systematically targeting and stationary, while the transition from Woodland to Built-up was systematically avoiding and stationary. PMID:24988380

Zhou, Pei; Huang, Jinliang; Pontius, Robert Gilmore; Hong, Huasheng

2014-01-01

399

Customary tenure systems under siege: contemporary access to land in Northern Ghana  

Microsoft Academic Search

Land in most of Africa is controlled under the customary tenure system which is governed by well intentioned social and cultural\\u000a rules meant to grant equal access to families within groups with common interest in land. Rapid changes in the domestic situation\\u000a of countries resulting from both refractions of policies and influences from the global economy and emerging complexities\\u000a within

Joseph Awetori Yaro

2010-01-01

400

Biogeophysical effects of historical land cover changes simulated by six Earth system models of intermediate complexity  

Microsoft Academic Search

Six Earth system models of intermediate complexity that are able to simulate interaction between atmosphere, ocean, and land\\u000a surface, were forced with a scenario of land cover changes during the last millennium. In response to historical deforestation\\u000a of about 18 million sq km, the models simulate a decrease in global mean annual temperature in the range of 0.13–0.25°C. The\\u000a rate of this cooling

V. Brovkin; M. Claussen; E. Driesschaert; T. Fichefet; D. Kicklighter; M. F. Loutre; H. D. Matthews; N. Ramankutty; M. Schaeffer; A. Sokolov

2006-01-01

401

Sensitivity analysis of a land surface scheme using multicriteria methods  

E-print Network

the theoretical and practi- cal basis for applying multicriteria methods to the generalized sensitivity analysis and energy balance, they are driven by multiple input variables (e.g., pre- cipitation, shortwave and longwave radiation, wind speed, air temperature, and humidity), and they predict the evolution of several

Yang, Zong-Liang

402

Storage battery systems analysis  

SciTech Connect

Storage Battery Systems Analysis supports the battery Exploratory Technology Development and Testing Project with technical and economic analysis of battery systems in various end-use applications. Computer modeling and simulation techniques are used in the analyses. Analysis objectives are achieved through both in-house efforts and outside contracts. In-house studies during FY82 included a study of the relationship between storage battery system reliability and cost, through cost-of-investment and cost-of-service interruption inputs; revision and update of the SOLSTOR computer code in standard FORTRAN 77 form; parametric studies of residential stand-alone photovoltaic systems using the SOLSTOR code; simulation of wind turbine collector/storage battery systems for the community of Kalaupapa, Molokai, Hawaii.

Murphy, K.D.

1982-01-01

403

Soil food web properties explain ecosystem services across European land use systems.  

PubMed

Intensive land use reduces the diversity and abundance of many soil biota, with consequences for the processes that they govern and the ecosystem services that these processes underpin. Relationships between soil biota and ecosystem processes have mostly been found in laboratory experiments and rarely are found in the field. Here, we quantified, across four countries of contrasting climatic and soil conditions in Europe, how differences in soil food web composition resulting from land use systems (intensive wheat rotation, extensive rotation, and permanent grassland) influence the functioning of soils and the ecosystem services that they deliver. Intensive wheat rotation consistently reduced the biomass of all components of the soil food web across all countries. Soil food web properties strongly and consistently predicted processes of C and N cycling across land use systems and geographic locations, and they were a better predictor of these processes than land use. Processes of carbon loss increased with soil food web properties that correlated with soil C content, such as earthworm biomass and fungal/bacterial energy channel ratio, and were greatest in permanent grassland. In contrast, processes of N cycling were explained by soil food web properties independent of land use, such as arbuscular mycorrhizal fungi and bacterial channel biomass. Our quantification of the contribution of soil organisms to processes of C and N cycling across land use systems and geographic locations shows that soil biota need to be included in C and N cycling models and highlights the need to map and conserve soil biodiversity across the world. PMID:23940339

de Vries, Franciska T; Thébault, Elisa; Liiri, Mira; Birkhofer, Klaus; Tsiafouli, Maria A; Bjørnlund, Lisa; Bracht Jørgensen, Helene; Brady, Mark Vincent; Christensen, Søren; de Ruiter, Peter C; d'Hertefeldt, Tina; Frouz, Jan; Hedlund, Katarina; Hemerik, Lia; Hol, W H Gera; Hotes, Stefan; Mortimer, Simon R; Setälä, Heikki; Sgardelis, Stefanos P; Uteseny, Karoline; van der Putten, Wim H; Wolters, Volkmar; Bardgett, Richard D

2013-08-27

404

Commercial and industrial land use change, job decentralization and growth controls: a spatially explicit analysis  

Microsoft Academic Search

This article studies the creation of commercial and industrial spaces and consequently jobs in suburban and exurban areas of Montgomery County, MD – part of the Washington, DC, metropolitan area. We utilize a spatially explicit framework of land use change analysis – which to date, has been applied solely in studies of residential decentralization and sprawl – to examine employment

Michail Fragkias; Jacqueline Geoghegan

2010-01-01

405

Distributive analysis of rural land size and price relationships  

E-print Network

12 Market Movements Frictional Adjustments Economies of Size 12 1". 13 Factors of Consideration Market Division Methodology Bases Percentages Blocks Groups Appreciation Market Distribution 15 17 18 19 20 20 23 24 The Models... Chapter Page VI. STATISTICAL ANALYSIS Sale Price 39 39 General Price Levels Significance Related to Blocks Appreciation Rates 39 39 44 Acres 50 General Price Levels Significance Related to Blocks Appreciation Rates 50 56 56 VII. SUMMARY...

Rothe, Robert Joseph

2012-06-07

406

Mars Phoenix Entry, Descent, and Landing Simulation Design and Modelling Analysis  

NASA Technical Reports Server (NTRS)

The 2007 Mars Phoenix Lander was launched in August of 2007 on a ten month cruise to reach the northern plains of Mars in May 2008. Its mission continues NASA s pursuit to find evidence of water on Mars. Phoenix carries upon it a slew of science instruments to study soil and ice samples from the northern region of the planet, an area previously undiscovered by robotic landers. In order for these science instruments to be useful, it was necessary for Phoenix to perform a safe entry, descent, and landing (EDL) onto the surface of Mars. The EDL design was defined through simulation and analysis of the various phases of the descent. An overview of the simulation and various models developed to characterize the EDL performance is provided. Monte Carlo statistical analysis was performed to assess the performance and robustness of the Phoenix EDL system and are presented in this paper. Using these simulation and modelling tools throughout the design and into the operations phase, the Mars Phoenix EDL was a success on May 25, 2008.

Prince, Jill L.; Desai, Prasun N.; Queen, Eric M.; Grover, Myron R.

2008-01-01

407

MOUSE UNCERTAINTY ANALYSIS SYSTEM  

EPA Science Inventory

The original MOUSE (Modular Oriented Uncertainty System) system was designed to deal with the problem of uncertainties in Environmental engineering calculations, such as a set of engineering cost or risk analysis equations. t was especially intended for use by individuals with li...

408

Space lab system analysis  

NASA Technical Reports Server (NTRS)

An analysis of the Automated Booster Assembly Checkout System (ABACS) has been conducted. A computer simulation of the ETHERNET LAN has been written. The simulation allows one to investigate different structures of the ABACS system. The simulation code is in PASCAL and is VAX compatible.

Rives, T. B.; Ingels, F. M.

1988-01-01

409

Dynamic analysis on urban land development based on remote sensing image and GIS technology  

NASA Astrophysics Data System (ADS)

Recent years, China's rapid economic development speeds up the process of urbanization, the most prominent is the rapid expansion of urban land. In this paper, remote sensing, GIS and statistical analysis techniques are used to analyze the dynamic process of land development of Wuhan city from 1995 to 2010, and its causes. Then the effectiveness of the urban master plan of Wuhan city in 1996 is evaluated. Finally, we analyze the possible reasons for the failure of urban planning, which will provide a reference for the future urban planning and management of Wuhan city.

Li, Xinyan; Xu, Zhe

2013-10-01

410

Land use classification utilizing remote multispectral scanner data and computer analysis techniques  

NASA Technical Reports Server (NTRS)

An airborne multispectral scanner was used to collect the visible and reflective infrared data. A small subdivision near Lafayette, Indiana was selected as the test site for the urban land use study. Multispectral scanner data were collected over the subdivision on May 1, 1970 from an altitude of 915 meters. The data were collected in twelve wavelength bands from 0.40 to 1.00 micrometers by the scanner. The results indicated that computer analysis of multispectral data can be very accurate in classifying and estimating the natural and man-made materials that characterize land uses in an urban scene.

Leblanc, P. N.; Johannsen, C. J.; Yanner, J. E.

1973-01-01

411

Land Use and Water Efficiency in Current and Potential Future U.S. Corn and Brazilian Sugarcane Ethanol Systems  

E-print Network

Land Use and Water Efficiency in Current and Potential Future U.S. Corn and Brazilian Sugarcane the current and potential future land use efficiency and water use of U.S. corn ethanol and Brazilian land and water use among potential future ethanol systems. Methods Domestic biofuel production from

412

Development of an air pollution evaluation system by linking air pollution total quantity control and land use management  

Microsoft Academic Search

This study considers air pollution total quantity control and land use management to establish a methodology for estimating unit emission loads of land use types. An air pollution evaluation system (APES) is developed, based on air pollution evaluation theory and procedure by linking air pollution total quantity control and land use management. The APES consists of an information management subsystem,

2001-01-01

413

The Watershed Planning System: A Tool for Integrated Land Use Management  

NASA Astrophysics Data System (ADS)

The challenge in Maryland and across the nation is allowing economic growth while protecting our environment. Maryland's Smart Growth policies provide a strong foundation for conserving resource land, minimizing nutrient loadings from new development, and revitalizing our urban/suburban communities. To assist local governments and communities, MDP has developed the Watershed Planning System (WPS). It is an analytical tool to conduct watershed-based assessments of the impacts of current and alternative programs and policies on land and water resources. The WPS consists of two GIS-based models, the Growth Management Simulation, and the Pollution Simulation Management models. The Growth Management Simulation Model estimates changes in land uses by watershed as a function of population and household projections, as well as state and county policies, regulations, and programs. The model allows evaluation of different future land use scenarios by changing assumptions associated with comprehensive plans and zoning, subdivision, and environmental regulations through which plans are implemented. The Pollution Simulation Management model evaluates the effects of pollution management alternatives on current land use and future land use conditions. The output provides a basis for selecting a feasible mix of management alternatives that can be implemented through program changes, such as: comprehensive plans, soil conservation and water quality plans, nutrient management programs, zoning and subdivision programs, and sensitive area protection programs, and through implementation of best management practices. The WPS has been applied in the 13 counties, Anne Arundel, Calvert, Charles, Howard, Montgomery, Prince George's, St. Mary's, Worcester, Cecil, Wicomico, Frederick, Carroll, and Harford, to address a variety of land use management, resource conservation, and pollution control objectives. In addition, the model has been used to produce statewide 2020 land use projections essential for sound land use planning.

Weller, D. G.

2002-05-01

414

Mixed breeding system in the hermaphroditic land slug Arion intermedius (Stylommatophora, Arionidae).  

PubMed

Theory suggests that hermaphroditic plants and animals should be either entirely outcrossing or entirely selfing. As such, very few hermaphroditic plants and basommatophoran snails have a mixed breeding system. However, reliable estimates of selfing rates are lacking for most hermaphroditic animals. This partly prevents to delineate the relative contributions of the selective factors that determine selfing and outcrossing rates in hermaphroditic animal taxa. Here, we studied the population genetic structure of, and breeding system in, 11 populations of the hermaphroditic land slug Arion intermedius using five polymorphic microsatellite loci. Moreover, genotype frequencies deviated significantly from Hardy-Weinberg equilibrium expectations for most of the loci in all populations suggesting some level of selfing. Estimates of the selfing level s, suggest moderate levels of outcrossing (mean s based on FIS = 0.84; mean s based on the two-locus heterozygosity disequilibrium = 0.20, or with a ML approach = 0.22). Our study therefore suggests that A. intermedius has a mixed breeding system. A re-analysis of allozyme data from another arionid slug ( subgenus Carinarion) indicates that mixed breeding may be more common in arionid slugs than hitherto was assumed. These results seem therefore at variance with current theoretical and empirical predictions and opens perspectives for the study on the evolutionary factors driving mixed breeding systems in animals. PMID:24164457

Jordaens, Kurt; Van Houtte, Natalie; Helsen, Philippe; Breugelmans, Karin; Jaksons, Peter; Backeljau, Thierry

2013-12-01

415

Traffic analysis zone level crash estimation models based on land use characteristics.  

PubMed

The objective of this paper is to develop crash estimation models at traffic analysis zone (TAZ) level as a function of land use characteristics. Crash data and land use data for the City of Charlotte, Mecklenburg County, North Carolina were used to illustrate the development of TAZ level crash estimation models. Negative binomial count models (with log-link) were developed as data was observed to be over-dispersed. Demographic/socio-economic characteristics such as population, the number of household units and employment, traffic indicators such as trip productions and attractions, and, on-network characteristics such as center-lane miles by speed limit were observed to be correlated to land use characteristics, and, hence were not considered in the development of TAZ level crash estimation models. Urban residential commercial, rural district and mixed use district land use variables were observed to be correlated to other land use variables and were also not considered in the development of the models. Results obtained indicate that land use characteristics such as mixed use development, urban residential, single-family residential, multi-family residential, business and, office district are strongly associated and play a statistically significant role in estimating TAZ level crashes. The coefficient for single-family residential area was observed to be negative, indicating a decrease in the number of crashes with an increase in single-family residential area. Models were also developed to estimate these crashes by severity (injury and property damage only crashes). The outcomes can be used in safety conscious planning, land use decisions, long range transportation plans, and, to proactively apply safety treatments in high risk TAZs. PMID:22785088

Pulugurtha, Srinivas S; Duddu, Venkata Ramana; Kotagiri, Yashaswi

2013-01-01

416

Cost analysis of water and sediment diversions to optimize land building in the Mississippi River delta  

NASA Astrophysics Data System (ADS)

Land loss in the Mississippi River delta caused by subsidence and erosion has resulted in habitat loss and increased exposure of settled areas to storm surge risks. There is debate over the most cost-efficient and geomorphologic