Optimal pilot decisions and flight trajectories in air combat

The thesis concerns the analysis and synthesis of pilot decision-making and the design of optimal flight trajectories. In the synthesis framework, the methodology of influence diagrams is applied for modeling and simulating the maneuvering decision process of the pilot in one-on-one air combat. The influence diagram representations describing the maneuvering decision in a one sided optimization setting and in a game setting are constructed. The synthesis of team decision-making in a multiplayer air combat is tackled by formulating a decision theoretical information prioritization approach based on a value function and interval analysis. It gives the team optimal sequence of tactical data that is transmitted between cooperating air units for improving the situation awareness of the friendly pilots in the best possible way. In the optimal trajectory planning framework, an approach towards the interactive automated solution of deterministic aircraft trajectory optimization problems is presented. It offers design principles for a trajectory optimization software that can be operated automatically by a nonexpert user. In addition, the representation of preferences and uncertainties in trajectory optimization is considered by developing a multistage influence diagram that describes a series of the maneuvering decisions in a one-on-one air combat setting. This influence diagram representation as well as the synthesis elaborations provide seminal ways to treat uncertainties in air combat modeling. The work on influence diagrams can also be seen as the extension of the methodology to dynamically evolving decision situations involving possibly multiple actors with conflicting objectives. From the practical point of view, all the synthesis models can be utilized in decision-making systems of air combat simulators. The information prioritization approach can also be implemented in an onboard data link system.reviewe

Increasing Combat Aircraft Survivability Through Coherent Self-Protection Jammers

When the battlefields were within the visual range, the objective of deception tactics in warfare was to deceive the human senses. In the battlefield of electromagnetic spectrum, the objective of deception is to deceive the sensors of the enemy weapon systems. The survivability of the aircraft operating in hostile environment is of prime importance to the mission planner. If the aircraft can deny its location information to the tracking radar of the radar guided threat missile system, this, in return, may increase its survivability. The deception, a tactic which stems from the wisdom of ancient battles, incarnated in the form of Electronic Attack (EA) can give this capability to the aircraft operating in a hostile environment. Self-Protection Jammers (SPJs) mounted on aircraft that employ deception-repeater jamming techniques and the resulting effect of the deception jamming on the enemy sensor systems will be examined in this study. The impact of the specific flight path and formation geometry should be considered both from the perspective of coherent SPJs effectiveness and the survivability. The individual effectiveness of the EA by SPJs is usually limited by the available Effective Radiated Power (ERP). Due to limitations on the size of the aircraft, one can not afford to build powerful SPJs. The jamming technique and the effect of multiple jammers with respect to jamming effectiveness need to be examined for mission planning analysis. The specific jamming technique evaluated is the combined Range Gate Pull-Off (RGPO) and Velocity Gate Pull-Off (VGPO) against pulse Doppler radar. The challenge is to decide the least vulnerable flight path and the formation geometry for a strike formation in an air-to-ground engagement scenario. The degree of survivability provided by the combination of the formation geometry, flight path and the EA (multiple spatially dispersed coherent jammers) is the focus of this research. The modeling and simulation of the interactions between the self-protection jammer and the pulse Doppler tracking radar with respect to formation geometry and flight path is the initial objective

Artificial Intelligence Research Branch future plans

This report contains information on the activities of the Artificial Intelligence Research Branch (FIA) at NASA Ames Research Center (ARC) in 1992, as well as planned work in 1993. These activities span a range from basic scientific research through engineering development to fielded NASA applications, particularly those applications that are enabled by basic research carried out in FIA. Work is conducted in-house and through collaborative partners in academia and industry. All of our work has research themes with a dual commitment to technical excellence and applicability to NASA short, medium, and long-term problems. FIA acts as the Agency's lead organization for research aspects of artificial intelligence, working closely with a second research laboratory at the Jet Propulsion Laboratory (JPL) and AI applications groups throughout all NASA centers. This report is organized along three major research themes: (1) Planning and Scheduling: deciding on a sequence of actions to achieve a set of complex goals and determining when to execute those actions and how to allocate resources to carry them out; (2) Machine Learning: techniques for forming theories about natural and man-made phenomena; and for improving the problem-solving performance of computational systems over time; and (3) Research on the acquisition, representation, and utilization of knowledge in support of diagnosis design of engineered systems and analysis of actual systems

Remote Sensing Applications in Coastal Environment

Coastal regions are susceptible to rapid changes, as they constitute the boundary between the land and the sea. The resilience of a particular segment of coast depends on many factors, including climate change, sea-level changes, natural and technological hazards, extraction of natural resources, population growth, and tourism. Recent research highlights the strong capabilities for remote sensing applications to monitor, inventory, and analyze the coastal environment. This book contains 12 high-quality and innovative scientific papers that explore, evaluate, and implement the use of remote sensing sensors within both natural and built coastal environments

Debris flows on Earth and Mars

This thesis explores the morphology of debris flows and their role in shaping planetary surfaces. The primary objective is to assess the scale of the present martian near-surface water budget by studying recent gullies visually similar to water-carved gullies on Earth. The potential involvement of debris flow in forming these gullies is important, because it implies the action of liquid water. To assess the role of debris flow in forming martian gullies requires a better understanding of debris flows on Earth. I first performed a detailed study of unconfined debris flows in NW Iceland and developed a model to predict their path and deposition thickness using only the morphology of the previous deposits. I used this model to define areas at risk from debris flow inundation. Secondly I have used quantitive geomorphological methods to study long profiles and digital elevation models and have successfully ascertained the geomorphic “fingerprint” of mass wasting, debris flow and pure water flow on Earth. Using these methods, I then confirmed that gullies on Mars contain the signature of debris flow. In addition, these investigations revealed a strong climatic signal in gully development. Laboratory simulation experiments showed that under present martian climate liquid water can not only survive for appreciable time-scales, but can perform significant geomorphic work. Freezing at the base of the flow not only decreases infiltration, but increases the runout of the flow. These results indicate that gullies are a product of the recent action of thaw of ice on Mars. I suggest that moderate orbital spin obliquity is required to form gullies (rather than high obliquity suggested previously), because this is consistent with their distribution, the time needed for their development, and their relative youth. Thus the surface of Mars has been wetter, more recently than previously thought

Caprock Canyonlands Archeology: A Synthesis of the Late Prehistory and History of Lake Alan Henry and the Texas Panhandle-Plains Volume I

Archeological investigations at Lake Alan Henry, in Garza and Kent Counties, Texas, between 1987 and 1993 generated much archeological data relevant to interpreting late Holocene human activities. This review goes beyond the project boundary to synthesize the late prehistory and history of the Texas Panhandle Plains, with special emphasis on the north-south band of rugged canyons found along the Caprock Escarpment, herein defmed as the Caprock Canyonlands. This synthesis looks at the human past from an ecological perspective, correlating shifts in subsistence, technology, and settlement patterns with inferred changes in paleoclimate, flora, and fauna. Past fluctuations in bison population size, undoubtedly related in many complex ways tn changes in climate and grassland biotic communities, are emphasized as critical ecological factors affecting long-term patterns of human habitation in the Southern Plains. In addition, other factors identified as having affected human subsistence and settlement are the region\u27s highly seasonal food supply, participation in inter- and extraregional exchange networks, and intercultural conflicts. With climatic conditions more or less comparable to those of today, Late Archaic (2000 B.C. to A.D. 200) peoples adopted a mobile hunting lifestyle and roamed across the vast grassland prairies of the southern High Plains and Rolling Plains in search of bison. Exotic burial artifacts indicate that these nomadic bands were involved in a vast exchange network extending at least as far as the Texas Gulf Coast and the mountainous regions of western Oklahoma and/or Trans-Pecos Texas. Beyond their heavy reliance on bison, however, not much is known about these peoples whose remains are defined archeologically as the Little Sunday complex. Their lifestyle disappeared or changed when bison populations dwindled during the transitional Archaic (A.D. 200 to 500). During a mesic interval spanning the Late Prehistoric I period (A.D. 500 to 110011200), Native peoples adopted a foraging strategy centered around intensive procurement and processing of wild plant foods, perhaps supplemented by limited horticulture, and accompanied by hunting of deer and smaller game. Presumably because of less-favorable grassland conditions, bison populations were so low that bison hunting was not a viable economic pursuit. There appear to have been at least two main groups of people inhabiting the Panhandle-Plains at this time. One group, archeologically recognized as the Lake Creek complex, may have originated from the westward spread of Plains Woodland peoples or ideas, while the other, called the Palo Duro complex, represents the eastward spread of Jornada Mogollon influence among Panhandle-Plains peoples. Burial evidence suggests that the peoples of these two divergent cultural traditions were hostile toward each other. Concomitant with a drying episode evident over all of the Southern Plains and much of the Greater Southwest, large numbers of bison returned to the Texas Panhandle-Plains around A.D. 1100, and Native peoples once again adopted bison hunting lifestyles during the Late Prehistoric II period (A.D. 1100/1200-1541). While peoples along the Canadian River in the northern Texas Panhandle adapted to the drier climate by incorporating horticulture and bison hunting within a Plains Village tradition, at least two groups living in the Caprock Canyonlands practiced nomadic bison hunting-foraging lifestyles. Defined archeologically as the Tierra Blanca and Garza complexes, either or both of these groups may represent new arrivals in the Southern Plains. Intersocietal exchange with sedentary Anasazi farmers became an important economic pursuit for the bison hunters during this period. Although complex and still poorly understood, the Panhandle-Plains groups continued to intensity their bison hunting and Pueblo trading activities throughout the Protohistoric period (A.D. 1541-1750). Increased mobility and hunting efficiency due to the acquisition of horses, along with increasing Spanish demand for bison products, further intensified the Plains-Pueblo exchange. Competition for hunting territory and trade alliances with sedentary peoples may have exacerbated hostilities between the two main groups of nomadic Southern Plains bison hunters

Caprock Canyonlands Archeology: A Synthesis of the Late Prehistory and History of Lake Alan Henry and the Texas Panhandle-Plains Volume I

Archeological investigations at Lake Alan Henry, in Garza and Kent Counties, Texas, between 1987 and 1993 generated much archeological data relevant to interpreting late Holocene human activities. This review goes beyond the project boundary to synthesize the late prehistory and history of the Texas Panhandle Plains, with special emphasis on the north-south band of rugged canyons found along the Caprock Escarpment, herein defmed as the Caprock Canyonlands. This synthesis looks at the human past from an ecological perspective, correlating shifts in subsistence, technology, and settlement patterns with inferred changes in paleoclimate, flora, and fauna. Past fluctuations in bison population size, undoubtedly related in many complex ways tn changes in climate and grassland biotic communities, are emphasized as critical ecological factors affecting long-term patterns of human habitation in the Southern Plains. In addition, other factors identified as having affected human subsistence and settlement are the region\u27s highly seasonal food supply, participation in inter- and extraregional exchange networks, and intercultural conflicts. With climatic conditions more or less comparable to those of today, Late Archaic (2000 B.C. to A.D. 200) peoples adopted a mobile hunting lifestyle and roamed across the vast grassland prairies of the southern High Plains and Rolling Plains in search of bison. Exotic burial artifacts indicate that these nomadic bands were involved in a vast exchange network extending at least as far as the Texas Gulf Coast and the mountainous regions of western Oklahoma and/or Trans-Pecos Texas. Beyond their heavy reliance on bison, however, not much is known about these peoples whose remains are defined archeologically as the Little Sunday complex. Their lifestyle disappeared or changed when bison populations dwindled during the transitional Archaic (A.D. 200 to 500). During a mesic interval spanning the Late Prehistoric I period (A.D. 500 to 110011200), Native peoples adopted a foraging strategy centered around intensive procurement and processing of wild plant foods, perhaps supplemented by limited horticulture, and accompanied by hunting of deer and smaller game. Presumably because of less-favorable grassland conditions, bison populations were so low that bison hunting was not a viable economic pursuit. There appear to have been at least two main groups of people inhabiting the Panhandle-Plains at this time. One group, archeologically recognized as the Lake Creek complex, may have originated from the westward spread of Plains Woodland peoples or ideas, while the other, called the Palo Duro complex, represents the eastward spread of Jornada Mogollon influence among Panhandle-Plains peoples. Burial evidence suggests that the peoples of these two divergent cultural traditions were hostile toward each other. Concomitant with a drying episode evident over all of the Southern Plains and much of the Greater Southwest, large numbers of bison returned to the Texas Panhandle-Plains around A.D. 1100, and Native peoples once again adopted bison hunting lifestyles during the Late Prehistoric II period (A.D. 1100/1200-1541). While peoples along the Canadian River in the northern Texas Panhandle adapted to the drier climate by incorporating horticulture and bison hunting within a Plains Village tradition, at least two groups living in the Caprock Canyonlands practiced nomadic bison hunting-foraging lifestyles. Defined archeologically as the Tierra Blanca and Garza complexes, either or both of these groups may represent new arrivals in the Southern Plains. Intersocietal exchange with sedentary Anasazi farmers became an important economic pursuit for the bison hunters during this period. Although complex and still poorly understood, the Panhandle-Plains groups continued to intensity their bison hunting and Pueblo trading activities throughout the Protohistoric period (A.D. 1541-1750). Increased mobility and hunting efficiency due to the acquisition of horses, along with increasing Spanish demand for bison products, further intensified the Plains-Pueblo exchange. Competition for hunting territory and trade alliances with sedentary peoples may have exacerbated hostilities between the two main groups of nomadic Southern Plains bison hunters

The Sixth Annual Workshop on Space Operations Applications and Research (SOAR 1992)

This document contains papers presented at the Space Operations, Applications, and Research Symposium (SOAR) hosted by the U.S. Air Force (USAF) on 4-6 Aug. 1992 and held at the JSC Gilruth Recreation Center. The symposium was cosponsored by the Air Force Material Command and by NASA/JSC. Key technical areas covered during the symposium were robotic and telepresence, automation and intelligent systems, human factors, life sciences, and space maintenance and servicing. The SOAR differed from most other conferences in that it was concerned with Government-sponsored research and development relevant to aerospace operations. The symposium's proceedings include papers covering various disciplines presented by experts from NASA, the USAF, universities, and industry