Telemetry word forming unit

Telemetry data unit to form multibit words for use between demodulator and compute

Evaluation of test procedures for hydrogen environment embrittlement

Report presents discussion of three common and primary influences on embrittlement process. Application of theoretical considerations to design of test coupons and methods is illustrated for both internal and external hydrogen embrittlement. Acceptable designs and methods are indicated

Reentry communication by material addition Patent

Reentry communication by injection of water droplets into plasma layer surrounding space vehicl

Low level accelerometer test methods are investigated

Problems associated with testing accelerometers to an accuracy where the standard error is less than .0000001 g are centered around the elimination of uncertainties in the acceleration input to the accelerometer. By placing a test rig in free fall, the uncertainty in the earths gravity field can be eliminated

Methodology for the systems engineering process. Volume 2: Technical parameters

A scheme based on starting the logic networks from the development and mission factors that are of primary concern in an aerospace system is described. This approach required identifying the primary states (design, design verification, premission, mission, postmission), identifying the attributes within each state (performance capability, survival, evaluation, operation, etc), and then developing the generic relationships of variables for each branch. To illustrate this concept, a system was used that involved a launch vehicle and payload for an earth orbit mission. Examination showed that this example was sufficient to illustrate the concept. A more complicated mission would follow the same basic approach, but would have more extensive sets of generic trees and more correlation points between branches. It has been shown that in each system state (production, test, and use), a logic could be developed to order and classify the parameters involved in the translation from general requirements to specific requirements for system elements

Frank Knight and original sin.

Frank Knight was the key person in founding the Chicago school of economics. In this respect he was a seminal figure in the history of twentieth century economics. Yet, few current economists know much about Knight. After his early success in 1921 with Risk, Uncertainty and Profit - Knight's work best known to current economists -- he wrote more in the manner of a moral philosopher than an economic scientist. This paper examines the thinking of the later Knight, the approach to social analysis that he adopted for most of career and including all of his years in the Chicago economics department. Knight was known for his antagonism to traditional Christian religion. Yet, penetrating only slightly below the surface, his thinking is revealed to follow closely in a Christian mode. Indeed, Knight's moral philosophy was a secular form of Calvinism. Rather than the pursuit of pleasure, human actions are driven by the fallen character of human nature since the expulsion from the Garden of Eden. Rather than maximization of utility, Knight's writings depict a world in which a more fundamental force in human behavior and events is a secular equivalent of original sin. As Knight developed the implications of this world view, he increasingly rejected the scientific management approaches of the mainstream of the economics profession and instead worked out his own brand of libertarian philosophy - anticipating and influencing later libertarian directions of thought that would emerge at Chicago.Moral philosophy; Chicago school; intellectual history; normative economics; religion

Assessment of forest plantations from low altitude aerial photography

Vertical color, and color-infrared, aerial photography obtained from altitudes between 183 m and 915 m provide a cost effective method of determining tree survival and height growth in pine plantations on the North Carolina Coastal Plain. All interpretations were performed by professional forestry personnel from the original 70 mm color transparencies. Prompt assessment of tree survival is necessary if failed spots are to be successfully replanted. Counts of living trees made after the third growing season, and sometimes only two growing seasons after planting, are accurate enough to permit planning of replanting operations without extensive ground surveys

Policy issues effecting entrance and lodging fees at National parks: options for Zimbabwe The Southern African Experiment.

The National Park System of Zimbabwe is a main attraction for foreign tourists and an important contributor to the economic well being of the country. It contains large numbers of elephants, lions and other types of magnificent African wildlife. The entrance and lodging fees currently charged of foreign visitors to Zimbabwe parks should be significantly altered. They are too low to serve as an effective restraint on the demands made by humans on ecological systems. They forego large potential revenues that could be achieved with a higher fee structure. The current charge at Victoria Falls of US $10 per foreign visitor per day, for example, could be increased to US$25 without much effect on total levels of visitation. Significant increases in entrance fees, as well as lodging rates, could also be made at other Zimbabwe parks. The higher revenues could be employed to provide better park visitor services and greater protection of park resources. Other desirable changes in policies for entrance fees and lodging rates for foreign visitors include: (1) wider variability in fees from one park to another; (2) smaller discounts for longer stays in a park; (3) half-price discounts for children up to age 18; (4) increased charges for noncommercial vehicles; (5) significantly higher rates for lodging facilities in Zimbabwe parks; and (6) major improvements in booking arrangements for park lodging. It is estimated that revised park entrance fee and lodging rate policies along these lines could roughly double the total revenues earned by the National Park System of Zimbabwe to a new level of perhaps US $10 million per year or more.Zimbabwe; national parks; tourism; economic development; ecological protection

A film-rupture model of hydrogen-induced, slow crack growth in alpha-beta titanium

The appearance of the terrace like fracture morphology of gaseous hydrogen induced crack growth in acicular alpha-beta titanium alloys is discussed as a function of specimen configuration, magnitude of applied stress intensity, test temperature, and hydrogen pressure. Although the overall appearance of the terrace structure remained essentially unchanged, a distinguishable variation is found in the size of the individual terrace steps, and step size is found to be inversely dependent upon the rate of hydrogen induced slow crack growth. Additionally, this inverse relationship is independent of all the variables investigated. These observations are quantitatively discussed in terms of the formation and growth of a thin hydride film along the alpha-beta boundaries and a qualitative model for hydrogen induced slow crack growth is presented, based on the film-rupture model of stress corrosion cracking