Attention is focussed on the asymptotic stress and deformation fields near the edge of a mode I crack propagating steadily in an elastic perfectly plastic incompressible material under plane strain conditions. Features of previously reported results on this problem are reviewed, with a view toward establishing discriminating characteristics. An asymptotic solution valid for all crack speeds is constructed. This solution has the properties that the angular variation of stress and particle...
Topics: DTIC Archive, Leighton, J T, BROWN UNIV PROVIDENCE RI DIV OF ENGINEERING, *CRACK PROPAGATION,...
Fractional factorial designs are among the most utilized statistical designs by practioners. In a series of three papers Rao (1946, 1947, 1949) identified special types of fractions with a great deal of symmetry and many desirable statistical properties. These special fractions are now known as orthogonal arrays. Numerous beautiful results have been obtained by both statisticians and mathematicians on this topic. These results are published in a wide variety of journals and presented in many...
Topics: DTIC Archive, Hedayat,A S, ILLINOIS UNIV AT CHICAGO CIRCLE DEPT OF MATHEMATICS STATISTICS AND...
The p-version of the finite element method is a new, important, computationally efficient, approach to finite element analysis. It is more robust than the conventional h-version and its rate of convergence, for domains with corners and for other singularity problems, is twice that of the h-version. Hierarchic elements which implement the p-version efficiently have been formulated so as to enforce C sub o or C sub 1 continuity in the planar case, and so as to enforce C sub o continuity in three...
Topics: DTIC Archive, Katz,I N, WASHINGTON UNIV ST LOUIS MO DEPT OF SYSTEMS SCIENCE AND MATHEMATICS,...
This report contains a review of all COMO Model Management and Maintenance efforts accomplished by the MICOM COMO Model manager during the period of October 1984 - September 1985. (Author)
Topics: DTIC Archive, Colvin,Charles E, ARMY MISSILE COMMAND REDSTONE ARSENAL AL SYSTEMS ANALYSIS AND...
The study describes how the Imperial Russian Army adapted its tactics and organization to conduct operations in a frontier environment and explains why some changes persisted and others did not. Keywords: Frontier warfare, History.
Topics: DTIC Archive, Menning, Bruce W, ARMY COMBINED ARMS CENTER FORT LEAVENWORTH KS SOVIET ARMY STUDIES...
Polyphosphazene work at NRDEC is reviewed in the light of the need for end items with resistance to flame and thermal hazards, low temperature flexibility, and resistance to petroleum solvents. The polyphosphazene polymers have been introduced into two end items, which are essentially gaskets. These items are discussed but, in general, emphasis is which are essentially gaskets. These items are discussed but, in general, emphasis is placed on attempts by the Natick RD&E Center to utilize the...
Topics: DTIC Archive, Laible, Roy C, ARMY NATICK RESEARCH DEVELOPMENT AND ENGINEERING CENTER MA,...
An analysis is developed for predicting the near zone fields scattered by perfectly-conducting, open-ended, semi-infinite circular and rectangular waveguides (or ducts) which are excited by an external electromagnetic (EM) plane wave. These waveguides are terminated inside by various structures such as a planar impedance surface, or a disk/blade structure with and without a hemispherical or a conical hub. The analysis is based on a combination of asymptotic high frequency techniques such as ray...
Topics: DTIC Archive, Pathak, P H, OHIO STATE UNIV COLUMBUS ELECTROSCIENCE LAB, *REFLECTION, *DIFFRACTION,...
Although human participation and influence are pervasive in actual combat, the effects of human performance are frequently considered only implicity, if at all in combat models. The need for better representation of the human element in combat models has frequently been identified during the past 30 years. However, the majority of the current analytic combat models provide a better representation of equipment capabilities than they do of the human component of weapon system. The purpose of this...
Topics: DTIC Archive, VanNostrand, Sally J., ARMY CONCEPTS ANALYSIS AGENCY BETHESDA MD, *COMBAT...
Topics: DTIC Archive, ASSISTANT SECRETARY OF DEFENSE (COMPTROLLER) WASHINGTON DC, *MILITARY PERSONNEL,...
This report contains the basic results from the 1985 Bulgarian Census.
Topics: DTIC Archive, *BULGARIA, *CENSUS, GOVERNMENT(FOREIGN), STATISTICAL DATA, POPULATION, MIGRATION,...
Partial Contents: Aeronautical and Space, Nuclear Energy, Non Nuclear Energy, Construction, Industrial Technology, Turbine and Engine Design , High Energy Devices, Optics and Photography,Fluid Mechanics, Mechanics of Solids, Testing and Materials.
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *NUCLEAR ENERGY, *INDUSTRIAL...
This paper presents an analytical solution to the operator algebraic Riccati equation (ARE) for selfadjoint parabolic systems. The solution to the operator ARE is important in the design of the steady state, on line filter for estimating the system's states. This analytical solution is derived by considering the operator analog of Potter's method of using the Hamiltonian system's eigenvectors and eigenvalues to solve a finite dimensional ARE. As an example of using this analytical solution, the...
Topics: DTIC Archive, Riddle,Laurence R, JOHNS HOPKINS UNIV BALTIMORE MD DEPT OF ELECTRICAL ENGINEERING AND...
This is the program maintenance manual for the Computer Aided Design System, CADS . CADS is a pre and post processor for structural analysis and optimization programs based on the finite element method. The system supports five functional modules controlled by an Executive Monitor. All of these modules communicate with a data base through a data manager. In addition a post output translator, CADSPP, is available which processes output from finite element programs, e.g. NASTRAN, directly into...
Topics: DTIC Archive, Less,Michael C, ROCKWELL INTERNATIONAL EL SEGUNDO CA NORTH AMERICAN AIRCRAFT DIV,...
Using second order closure turbulence model to predict turbulent flows is known to be more successful than the classical mixing length model. To improve the predictability of the second order closure model, work proposes to consider two turbulent scales in the modelling turbulent flows. One scale is based on using the turbulent kinetic energy, k, and its dissipation rate, e, to characterize the large energy containing eddies. The other scale is based on the dissipation rate and the kinematic...
Topics: DTIC Archive, Chen, Ching-Jen, IOWA INST OF HYDRAULIC RESEARCH IOWA CITY, *DISSIPATION,...
Canadian Forces ships use air conditioning plants that supply hydronic water via a network of pipes, fittings and pumps that distribute the water to fan coil units throughout the ship. Hydronic water is a 90:10 mixture of fresh water and ethylene glycol which is chilled to 4.4 C by the air conditioning plants, or heated to 60 C by hot water converters. A hydronic water system is designed to be fabricated from copper or copper alloy components to minimize corrosion. As a result of an...
Topics: DTIC Archive, Hanham,C M, DEFENCE RESEARCH ESTABLISHMENT ATLANTIC DARTMOUTH (NOVA SCOTIA),...
An investigation of the power of the Euler equations in the prediction of supersonic separated flows is presented. These equations are solved numerically for the highly vortical flow about simple bodies. Two sources of vorticity are studied: the first is the flow field shock system and the second is the vorticity shed into the flow field from a separating boundary layer. Both sources of vorticity are found to produce separation and vortices. In the case of shed vorticity the surface point from...
Topics: DTIC Archive, Marconi,Frank, GRUMMAN CORP BETHPAGE NY CORPORATE RESEARCH CENTER, *VORTICES, *VORTEX...
Octane requirement increase (ORI) was determined for sixty-two 1984 model cars and trucks operated on unleaded gasoline. The cars tested were not selected to represent the distribution of vehicles produced in the model year; rather the data base consists of information volunteered by participants. All ORI values were determined from the increase in maximum octane requirements irrespective of whether requirements were obtained at full- or part-throttle. Though the sample size is smaller than in...
Topics: DTIC Archive, COORDINATING RESEARCH COUNCIL INC ATLANTA GA, *GASOLINE, DATA BASES, REQUIREMENTS,...
The probabilistic performance of a number of algorithms for the NP-complete satisfiability Problem (SAT) has been investigated analytically and experimentally using a fixed-clause-length model generating n clauses of k - 3 literals taken from r variables as well as a random-clause-length model generating n clauses containing each of r variables independently with probability P. In the case of the random instance I of SAT with probability approachingas in and r get large when a solution exists...
Topics: DTIC Archive, Franco,John, INDIANA UNIV AT BLOOMINGTON DEPT OF COMPUTER SCIENCE, *ALGORITHMS,...
The theoretical predicted fatigue life of a high strength steel tube which has undergone an autofrettage procedure is significantly higher than the experimental prediction. To account for the discrepancy, attention is now turned to developing better elastic-plastic models for a high strength steel. An improved material model shows that reverse yielding may occur in the inner portion of the tube. This reverse yielding reduces the residual compressive hoop stress considerably which has an adverse...
Topics: DTIC Archive, Pu,S L, ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY CLOSE...
Capacitive sensor arrays have been developed for multifunction sensing in robotic applications. The arrays consist of one-dimensional arrays of strip electrodes. They can be addressed to provide the different functions enumerated in 18. Distance ranging, edge detection, response optimization, and matched filtering have all been demonstrated experimentally with metal samples. Edge detection has been observed with dielectric samples, which cannot be sensed with inductive probes. Keywords include:...
Topics: DTIC Archive, Auld,B A, STANFORD UNIV CA EDWARD L GINZTON LAB OF PHYSICS, *DETECTION, *DETECTORS,...
This paper describes ARLO, a representation language language loosely modelled after Greiner and Lenat's RLL-1. ARLO is a structure-based representation language for describing structure-based representation languages, including itself. A given representation language is specified in ARLO by a collection of structures describing how its descriptions are interpreted, defaulted, and verified. This high level description is compiled into LISP code and ARLO structures whose interpretation fullfills...
Topics: DTIC Archive, Haase,Kenneth W , Jr, MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE...
A numerical model has been applied that computes the behavior of a dredged material disposal through three phases: convective descent, during which the disposal cloud falls under the influence of gravity; bottom collapse, occurring when the descending cloud impacts the bottom; and passive transport- diffusion, commencing when the material transport and spreading are determined more by ambient currents and turbulence than by the dynamics of the disposal operation. The model accounts for land...
Topics: DTIC Archive, Trawle, Michael J, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS HYDRAULICS...
The Defense Mapping Agency (DMA) is currently producing a series of Mapping, Charting and Geodesy (MC/G) Video Discs as a standard product to support the DoD MC/G user community. The series consists of 39 Constant Angular Velocity 12 inch MC/G Video Discs. The MC/G Video Discs are organized in a structure that allows an indexing system to locate and retrieve individual frames from each disc. To use the MC/G Video Disc requires a video disc player, a display monitor and a micro/mini computer...
Topics: DTIC Archive, Edwards,Jerry F, DEFENSE MAPPING AGENCY HYDROGRAPHIC/ TOPOGRAPHIC CENTER WASHINGTON...
The hydrothermal durability of adhesive bonds is currently an active area of research. This work focuses on titanium/epoxy bonding using metal alkoxide primers as adhesive promoters. Pike showed that sec-butyl aluminum alkoxide enhances the durability of PAA (phosphoric acid anodized) and FPL (Forest Products Lab) etched 2024 aluminum bonded with the wedge test using epoxy adhesives. No variation in bond performance was observed when the cure temperature of the alkoxide film was varied....
Topics: DTIC Archive, Filbey,J A, VIRGINIA TECH CENTER FOR ADHESION SCIENCE BLACKSBURG, *ALUMINUM OXIDES,...
In the accelerating flow of a lighter continuous phase through a heavier one, small non-uniformities grow into large ones due to the Rayleigh-Taylor Instability. An experiment exemplifying the large 'bubble' formation due to Rayleigh-Taylor Instability has been performed and simulated using the PHOENICS 84 computer code. The same numerical procedure was applied to the two-phase flow in a gun barrel. It showed that the acceleration provided by the movement of the projectile can cause initial...
Topics: DTIC Archive, Farwagi,S M, IMPERIAL COLL OF SCIENCE AND TECHNOLOGY LONDON (ENGLAND), *TWO PHASE...
The area was settled during the Spanish Colonial Period (1763-1803) by Acadian immigrants. During the nineteenth century, several sugar plantations developed in the project area, although farmsteads continued to exist. A lumber yard and the Central Sugar Factory were established near the project corridor by the end of the 1800s. Eight sites were recorded during archeological survey. Sites 16SJ41, 16SJ43, 16SJ43, 163J44, 162J46, 16SJ47, and 16SJ48 all yielded small collections of habitation...
Topics: DTIC Archive, GOODWIN (R CHRISTOPHER) AND ASSOCIATES INC NEW ORLEANS LA, *ARCHEOLOGY, DEPOSITS,...
A numerical investigation of finite-volume techniques using the inviscid Burgers equation was conducted. An explicit, second-order, one-sided, or upwind differencing scheme developed by Warming and Beam was used. First, the difference scheme was analyzed for consistency, stability, convergence, phase and dispersion error, and artificial dissipation. Then, various combinations of finite-volume and extrapolation techniques were tested and conclusions and recommendations for their use were...
Topics: DTIC Archive, Mounts,Jon S, AIR FORCE ARMAMENT LAB EGLIN AFB FL, *NUMERICAL ANALYSIS, *FINITE...
Results from a recent sea surface acoustic scattering experiment, conducted in the North Sea, are presented with accompanying sea surface roughness parameters and subsurface bubble information. The acoustic data were obtained using a high resolution (narrow beamwidth) pulsed parametric sonar transmitter and conventional receiver. Scattering strength values were obtained as a function of frequency (3-18 kHz) for wind speeds from 2 to 45 knots. It appears that the backscattering strength at a 30...
Topics: DTIC Archive, Koenigs,Paul D, NAVAL UNDERWATER SYSTEMS CENTER NEWPORT RI, *BACKSCATTERING,...
This report serves as a source manual of raptors occurring on Army Corps of Engineers lands in the Pacific Northwest. It consists primarily of a comprehensive literature review covering aspects of the biology of 35 species of eagles, hawks, falcons, vultures, and owls. The manual was developed to provide biologists and resource managers with background information to facilitate the application of sound raptor management practices on project lands. While the literature is cosmopolitan,...
Topics: DTIC Archive, Fleming,Tracy L, ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS...
Automated scheduling of Army training can reduce the complexity of scheduling the many required training and nontraining activities for a unit and lead to better planning of training. The objective of the research described here was to develop a prototype program for applying a particular heuristic called simulated annealing to the scheduling of Army unit training. The report presents an analysis of scheduling needs in Army units and describes the simulated annealing approach to Army...
Topics: DTIC Archive, Hart, Roland J, ARMY RESEARCH INST FOR THE BEHAVIORAL AND SOCIAL SCIENCES ALEXANDRIA...
Radiowave scintillation in the presence of ionospheric disturbances has the potential to disrupt numerous transionospheric radio and radar systems. This report describes development of a model characterizing the plasma density irregularities that produce scintillation in the naturally disturbed mid latitude F layer. The model will be incorporated into Program WBMOD, which includes subroutines for computing both link geometry and scintillation indices, the latter by means of phase screen...
Topics: DTIC Archive, Robins,Robert E, NORTHWEST RESEARCH ASSOCIATES INC BELLEVUE WA, *IONOSPHERIC...
This report compares several lexicons used in computational text generation systems, with respects to the size of the lexical item, the way occurrence phenomena are represented, and the way semantic information is included. The lexicons examined can be roughly divided into two principal groups with respect to the size of the item, phrasal lexicons and word-based lexicons. Phrasal lexicons, which are more numerous, have large units (sometimes whole sentences) stored as lexical entries. They...
Topics: DTIC Archive, Cumming,Susanna, UNIVERSITY OF SOUTHERN CALIFORNIA MARINA DEL REY INFORMATION...
Incidence of non-Hodgkin's lymphomas was examined in a prospective study of all white U.S. Navy enlisted men during 1974-83 to test for existence of any short-term risk possibly related to occupation. A total of 103 cases were detected during active service. Examination of pathology records and specialist board reviews confirmed 68 cases: 44 diffuse; 13 nodular; and 11 unspecified or other. Risk was unrelated to length of service, and no occupational group in the Navy showed a significant...
Topics: DTIC Archive, Garland, Frank C, NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA, *LYMPHOMAS, *HEALTH...
Volz has monitored the Arago and Babinet neutral points at Lexington and Bedford, Mass. for the years 1968 to 1986. Theses data, along with measurements of turbidity, twilight color ratio, solar aureole and cloud and snow cover, have been assembled into a database and checked for error. The neutral point data were then corrected for day to day variations in tropospheric turbidity and separated into groups which coincide with time periods of known volcanic influences and seasonal events. 3-D...
Topics: DTIC Archive, Longtin, David R, OPTIMETRICS INC BURLINGTON MA, *DUST CLOUDS, *POLARIZATION,...
During the first period of the contract a computer program has been adapted for use on an HP 9836CS desk computer. The device fabrication processes are presently being developed in order to improve yield. Reactive ion etching has been found to be of key importance for fabricating the overlapping gate cathode contact which is the key feature of the FECTED. Standard microstrip circuits have been designed and fabricated for testing the devices at Ka-band (26-40GHz). Keywords: Computer simulation;...
Topics: DTIC Archive, Thim, Hartwig W, JOHANNES KEPLER UNIV LINZ (AUSTRIA) MICROELECTRONICS INST,...
The design of a parallel programming environment specialized to systolic computation is proposed. The system, called Hearts, is a dialect of the Poker parallel programming environment. The key feature of Hearts that enables it to be a convenient and efficacious facility for writing systolic programs is a novel concept of program that is graphical rather than textual. The use of this program form is illustrated in a full example of the Kung-Leiserson matrix product algorithm.
Topics: DTIC Archive, Snyder, Lawrence, WASHINGTON UNIV SEATTLE, *COMPUTER PROGRAMMING, *HIGH LEVEL...
This report contains translations/transcriptions of articles and/or broadcasts from China. Topics include: international trade, agriculture, policy and economics.
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *AGRICULTURE, *CHINA, *FARM CROPS,...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *POLITICAL SCIENCE, *INTERNATIONAL...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *SUBSAHARAN AFRICA, POLITICAL...
JPRS publications contain information primarily from foreign newspapers, periodicals and books, but also from news agency transmissions and broadcasts. Materials from foreign-language sources are translated; those from English-language sources are transcribed or reprinted, with the original phrasing and other characteristics retained. This report from Sub-Saharan Africa, Angola, Equatorial Guinea, Lesotho, Namibia, Zambia and South Africa, contains articles on Economic, Political and...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *POLITICAL SCIENCE, *SUBSAHARAN...
This report from Western Europe contains articles on Political, Social, Economic and Military Affairs.
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *POLITICAL SCIENCE, *ECONOMICS,...
This report from Eastern Europe contains articles on Politics, Economics and Sociology.
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *POLITICAL SCIENCE, *FINANCIAL...
The report contains information on national development and status of energy production in China with particular attention to technological progress and economical effectiveness in coal and oil industries. The report highlights and covers research and development in nuclear fission reactors with a focus on nuclear safety engineering and progress of construction of nuclear power plants. The issues of power network, hydroelectricity and thermal power are altogether discussed in detail.
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *ELECTRIC POWER PRODUCTION,...
Partial Contents: Warsaw Pact, Armed Forces, Air/Air Defense Forces, DOSAAF, Military Educational Facilities, Military History, Foreign Military Affairs.
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *MILITARY FACILITIES, *MILITARY...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *MILITARY FORCES(FOREIGN), AIR...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *DOMESTIC, *INTERNATIONAL...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *AUTOMOTIVE VEHICLES, RAIL...
Topics: DTIC Archive, JOINT PUBLICATIONS RESEARCH SERVICE ARLINGTON VA, *GOVERNMENT(FOREIGN),...
Hypoxia at high altitude could depress cardiac function and decrease exercise capacity. If so, impaired cardiac function should occur with the extreme, chronic hypoxemia of the 40 day simulated climb of Mt. Everest (8840m, Pa 240 mmHg, PIO2 43 mmHg). In the 5 subjects having resting and exercise measurements at the barometric pressures of 760 (sea level), 347 (6100m), 282 (7620m), and 240 mmHg, heart rate for a given oxygen uptake rose with the progressive hypoxia. Slight (6 beats/min) slowing...
Topics: DTIC Archive, Reeves,John T, COLORADO UNIV HEALTH SCIENCES CENTER DENVER, *HIGH ALTITUDE, *HYPOXIA,...
This article introduces the status and results of the use of a type of large-scale internal optical path vacuum stressing laser holographic nondestructive testing instrument in checking for viscosity flaws along layer surfaces of fuel packs in the motors of solid fuel rockets. Moreover, it discusses the advantages and disadvantages of carrying out this type of check using methods incorporating thermal stressing and vacuum(low pressure) stressing.
Topics: DTIC Archive, Geng, Wan-Zhen, FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH, *HOLOGRAPHY, *ROCKET...
