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All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

A Comparison Between Raman Lidar and Conventional Contact Measurements of Atmospheric Temperature

Described here are the results of comparison between lidar and conventional contact measurements of the vertical temperature profile of the atmosphere. The lidar measurements are based on the method of temperature dependence of pure rotational Raman scattering of nitrogen and oxygen molecules. The presented results show that, as a whole, the motion of the lidar and conventional profiles coincide in the confidence intervals. Still there are districts in which the differences lay out of the confidence intervals. In analysis and estimation of the coincidence and the distinction in moving the profiles, we must take into account the differences between the methods for measuring the temperature profiles by lidar and contact methods, i.e. the next additional factors. The tied balloon meter gives the momentary values of the temperature in particular points of the profile, as these momentary values are the results of consequent, but not simultaneous measurements. In the case of free flying balloon, the time of measuring the lower several hundred meters is little because of high vertical velocity (about 300 m/min). This leads to an indefinite increase of the measuring error. The complete space coincidence between the lidar's and conventional profiles isn't possible. The contribution of the factors mentioned above about the error of comparison could increase because of nonstable layers in the planetary boundary layer of the atmosphere as well as by the influence of the mountains and the city situated nearby.

Mitev, V. M.↗
NASA NTRS1992

A geodetic laser radar rangefinder with 10(exp -7) resolution

A novel geodetic laser radar rangefinder (GLRR) unit utilizing a pair of synchronized 10-psec streak camera systems was developed for displacement measurements of the earth's plates. In order to achieve minimum computing error and assure extremely high spatial resolution, an optical pulse registration clock was developed and used to register a fiducial mark on the time scale of the system. Conventional optical rangefinders have been limited to a relative resolution of 10(exp -6) even for short distances. The system to be reported on today has the capability of measuring a 50km range with an accuracy of 4mm corresponding to a relative resolution of 10(exp -7). With a gain of greater than 3 x 10(exp 3), the system has the capability of detecting extremely weak signals on the order of photon counting. This combined with temporal gating makes daytime measurements comparable in signal-to-noise ratio to nighttime viewing. This is useful for measuring faint signals returning over a range of several tens of kilometers. The present ranging system was designed to observe the mutual displacement of geodetic plates and was employed to measure the boundary between the Philippine and Asian geodetic plates that pass beneath the Suruga Bay near Hamamatsu City, Japan. The system has been in operation for over 3 years. In addition, the system has the ability of producing and detecting optical ranging pulses of several wavelengths simultaneously, making this a complete multicolor system. The basic GLRR system consists of a frequency stabilizing crystal, optical clock, YAG laser, KDP doubling crystal, DK*P tripling crystal, two matched streak cameras (A and B), a control computer, and an output/input periscope system.

Mizushima, Y.↗
NASA NTRS1991

A Great Salt Lake waterspout

Results are presented of observations of a waterspout funnel and spray ring performed under a cumulus line over the Great Salt Lake for about 5 min shortly after sunrise on June 26, 1985. These observations were used as the basis for a study of the initiation and evolution of waterspouts through a series of numerical experiments at two scales, that of a cloud and a waterspout. The cloud scale was simulated using an improved Goddard-Schlesinger model with nearby Salt Lake City soundings. Results showed that for each mode of cloud initiation, the vortex that started at the anticyclonic center grew faster than those started at other centers. This result strongly suggests that the cloud vorticity was important in its initiation. The greatest azimuthal speed for the bubble-initiated cloud was 11 m/s, when the vortex model was started at 28-min cloud time with time-varying boundary conditions, whereas it was 21 m/s when started at 12 min in the line-initiated cloud. The results support the hypothesis that, at least in some circumstances, cloud processes alone can produce waterspouts in the absence of external vorticity sources such as surface convergence lines or other shear features.

Simpson, Joanne↗
NASA NTRS1992

Hong Kong is an impact crater: Proof from the geomorphological and geological evidence

Hong Kong is a city in southern China. The urban districts of Hong Kong, Kowloon, and Victoria Harbour are situated within Hong Kong. Hong Kong is surrounded by mountains with a diameter of 11 km. Three million people live inside the basin. The round structure of the mountains in Hong Kong has been describd as a granite dome that is deeply eroded (batholith). The circularity of the mountains, the existence of a central hill, the inner slope of the mountains being greater than the outer slope, the presence of deep layer rock inside the basin, and the depth-to-diameter ratio were studied. All this evidence shows that the Hong Kong structure satisfies the geomorphological requirement of an impact crater. Some shock metamorphic phenomena of the rocks in Hong Kong such as planar features, microspherilitic silica glass (lechaterlierite), fused margins of rock fragments, concussion fractures, impact glass in which some schlierens are consistent with pyroxene spiculites, etc., were first discovered in Oct. 1990. In Hong Kong Island, an impact melt sheet was observed from the Victoria Peak to the southern shore. Quenching fractures of quartz in Kowloon fine-grained granite was also discovered. In our work, the K-Ar age (83.34 + 1.26 m.y.) of the impact melt rock, which is younger in comparison to the K-Ar age (117 m.y.) in Hong Kong and Kowloon granite, was measured, and the phenomena indicate that after the granite body formed, there was another geologic event. Maybe it is the Hong Kong cratering event.

Chan, Chu-Lok↗
NASA NTRS1993

Integrated flexible manufacturing program for manufacturing automation and rapid prototyping

The Kansas City Division of Allied Signal Inc., as part of the Integrated Flexible Manufacturing Program (IFMP), is developing an integrated manufacturing environment. Several systems are being developed to produce standards and automation tools for specific activities within the manufacturing environment. The Advanced Manufacturing Development System (AMDS) is concentrating on information standards (STEP) and product data transfer; the Expert Cut Planner system (XCUT) is concentrating on machining operation process planning standards and automation capabilities; the Advanced Numerical Control system (ANC) is concentrating on NC data preparation standards and NC data generation tools; the Inspection Planning and Programming Expert system (IPPEX) is concentrating on inspection process planning, coordinate measuring machine (CMM) inspection standards and CMM part program generation tools; and the Intelligent Scheduling and Planning System (ISAPS) is concentrating on planning and scheduling tools for a flexible manufacturing system environment. All of these projects are working together to address information exchange, standardization, and information sharing to support rapid prototyping in a Flexible Manufacturing System (FMS) environment.

Brooks, S. L.↗
NASA NTRS1991

Hybrid neural network and fuzzy logic approaches for rendezvous and capture in space

The nonlinear behavior of many practical systems and unavailability of quantitative data regarding the input-output relations makes the analytical modeling of these systems very difficult. On the other hand, approximate reasoning-based controllers which do not require analytical models have demonstrated a number of successful applications such as the subway system in the city of Sendai. These applications have mainly concentrated on emulating the performance of a skilled human operator in the form of linguistic rules. However, the process of learning and tuning the control rules to achieve the desired performance remains a difficult task. Fuzzy Logic Control is based on fuzzy set theory. A fuzzy set is an extension of a crisp set. Crisp sets only allow full membership or no membership at all, whereas fuzzy sets allow partial membership. In other words, an element may partially belong to a set.

Berenji, Hamid R.↗
NASA NTRS1993

Annular Solar Eclipse of 10 May 1994

An annular eclipse of the Sun will be widely visible from the Western Hemisphere on 10 May 1994. The path of the Moon's shadow passes through Mexico, the United States of America, maritime Canada, the North Atlantic, the Azores and Morocco. Detailed predictions for this event are presented and include tables of geographic coordinates of the annular path, local circumstances for hundreds of cities, maps of the path of annular and partial eclipse, weather prospects, and the lunar limb profile.

Espenak, Fred↗
NASA NTRS1992

CSU FIRE 2 cirrus field experiment: Description of field deployment phase

The Colorado State University (CSU) surface observing systems are described. These systems were deployed at the Parsons, Kansas site during the FIRE 2 Cirrus Special Observing Period (SOP) from 13 Nov. - 7 Dec. 1991. The geographical coordinates of the site containing most of the CSU instrumentation are 37 deg. 18 min N. latitude and 96 deg. 30 min. W. longitude; site elevation was 269 meters. In addition, one surface meteorological and broadband flux observing site was maintained at the Tri City Airport which is approximately 18 miles due west of Parsons (37 deg. 20 min. N. latitude, 95 deg. 30 min. 30 sec. W. longitude). A map of the locations of the CSU deployment sites is presented. At the main Parsons site, the instrumentation was located directly adjacent to and north of a lake. Under most cirrus observing conditions, when the wing had a significant southernly component, the lake was upwind of the observing site. The measurements and observations collected during the experiment are listed. These measurements may be grouped into five categories: surface meteorology; infrared spectral and broadband measurements; solar spectral and broadband measurements; upper air measurements; and cloud measurements. A summary of observations collected at the Parsons site during the SOP are presented. The wind profiler, laser ceilometer, surface meteorology and surface broadband radiation instrumentation were operated on a continuous basis. All other systems were operated on an 'on demand' basis when cloud conditions merited the collection of data.

Cox, S.↗
NASA NTRS1992

Free tropospheric ozone production following entrainment of urban plumes into deep convection

It is shown that rapid vertical transport of air from urban plumes through deep convective clouds can cause substantial enhancement of the rate of O3 production in the free troposphere. Simulation of convective redistribution and subsequent photochemistry of an urban plume from Oklahoma City during the 1985 PRESTORM campaign shows enhancement of O3 production in the free tropospheric cloud outflow layer by a factor of almost 4. In contrast, simulation of convective transport of an urban plume from Manaus, Brazil, into a prestine free troposphere during GTE/ABLE 2B (1987), followed by a photochemical simulation, showed enhancement of O3 production by a factor of 35. The reasons for the different enhancements are (1) intensity of cloud vertical motion; (2) initial boundary layer O3 precursor concentrations; and (3) initial amount of background free tropospheric NO(x). Convective transport of ozone precursors to the middle and upper troposphere allows the resulting O3 to spread over large geographic regions, rather than being confined to the lower troposphere where loss processes are much more rapid. Conversely, as air with lower NO descends and replaces more polluted air, there is greater O3 production efficiency per molecule of NO in the boundary layer following convective transport. As a result, over 30 percent more ozone could be produced in the entire tropospheric column in the first 24 hours following convective transport of urban plumes.

Pickering, Kenneth E.↗
NASA NTRS1991

Observations and analysis of oil spills using polarized imagery

On Saturday, July 28, 1990, a train of barges collided with the Greek tanker Shinoussa in Galveston Bay off Red Fish Island near Texas City, Texas. The first barge sank and the second began to leak while the third barge in the chain and the Shinoussa both escaped without damage. The NASA Flight Science Support Office sponsored a graduate student from SUNY - College of Environmental Science and Forestry and a student from Texas, to survey the damage. The purpose of these surveys was to correlate aircraft base data with orbital data obtained during the Space Shuttle Polarization Experiment and existing laboratory data to evaluate the potential for an application such as oil spill monitoring and mapping. NASA has no charter with the local response agencies to support oil spill monitoring and cleanup.

Israel, S. A.↗
NASA NTRS1992

A modular software system for distributed telerobotics

The authors describe a control architecture for telerobotics research. The architecture was object-oriented and data-driven, and can be distributed over many processors on a wide-area network (WAN). The basic capabilities of this testbed have already been demonstrated in tests distributed over four cities. The data distribution techniques of this control architecture are described, as well as details of the current implementation and experimental results.

Graves, Sean↗
NASA NTRS1992

Earth observations during Space Shuttle mission STS-45 Mission to Planet Earth - March 24-April 2, 1992

A description is presented of the activities and results of the Space Shuttle mission STS-45, known as the Mission to Planet Earth. Observations of Mount St. Helens, Manila Bay and Mt. Pinatubo, the Great Salt Lake, the Aral Sea, and the Siberian cities of Troitsk and Kuybyshev are examined. The geological features and effects of human activity seen in photographs of these areas are pointed out.

Pitts, David E.↗
NASA NTRS1922

European air travel in 1922

This article discusses the different passenger air transport services offered in Europe. The author deals mainly with the service offered between different cities, in terms of time and cost.

Warner, Edward P↗
NASA NTRS1993

Space Station redesign option A: Modular buildup concept

In early 1993, President Clinton mandated that NASA look at lower cost alternatives to Space Station Freedom. He also established an independent advisory committee - the Blue Ribbon Panel - to review the redesign work and evaluate alternatives. Daniel Goldin, NASA Administrator, established a Station Redesign Team that began operating in late March from Crystal City, Virginia. NASA intercenter teams - one each at Marshall Space Flight Center, Johnson Space Center, and Langley Research Center provided engineering and other support. The results of the Option A study done at Marshall Space Flight Center are summarized. Two configurations (A-1 and A-2) are covered. Additional data is provided in the briefing package MSFC SRT-001, Final System Review to SRT-002, Space Station Option A Modular Buildup Concept, Volumes 1-5, Revision B, June 10, 1993. In June 1993, President Clinton decided to proceed with a modular concept consistent with Option A, and asked NASA to provide an Implementation Plan by September. All data from the Option A redesign activity was provided to NASA's Transition Team for use in developing the Implementation Plan.

Source record↗
NASA NTRS1993

Qualification test of the Ross Double Planetary Mixer

This test report describes the qualification test of the Ross Double Planetary Mixer used to mix room temperature vulcanized (RTV) silicone (Dow Corning 90-006-2) for the redesigned solid rocket motor (RSRM) nozzle joints. Testing was completed 18 June 1993 in the M-113A Nozzle Fabrication Facility at Thiokol Corporation, Space Operations, Brigham City, Utah. The Ross mixer provides better mixing and better control on temperature and humidity, resulting in better quality RTV and a longer usable pot life. The test began on 3 May 1993 and was stopped due to operator error during the tensile strength and elongation testing. Specimens were ruined without gathering any useful data. A 'no test' was declared, the problem was remedied, and the test was re-run with MSFC approval. The test was run and all pass/fail criteria were met, most with a considerable margin. The Ross Double Planetary Mixer met all certification objectives and is recommended for immediate use for mixing RTV silicone for RSRM nozzle joints.

Lueders, Kurt F.↗
NASA NTRS1993

Total solar eclipse of 3 November 1994

A total eclipse of the Sun will be visible from the southern half of the Western Hemisphere on 3 November 1994. The path of the Moon's shadow passes through Peru, Chile, Bolivia, Paraguay, and Brazil. Detailed predictions for this event are presented and include tables of geographic coordinates of the path of totality, local circumstances for hundreds of cities, maps of the path of total and partial eclipse, weather prospects, and the lunar limb profile.

Espenak, Fred↗
NASA NTRS1993

Teaching planetary sciences to elementary school teachers: Programs that work

Planetary sciences can be used to introduce students to the natural world which is a part of their lives. Even children in an urban environment are aware of such phenomena as day and night, shadows, and the seasons. It is a science that transcends cultures, has been prominent in the news in recent years, and can generate excitement in young minds as no other science can. Planetary sciences also provides a useful tool for understanding other sciences and mathematics, and for developing problem solving skills which are important in our technological world. However, only 15 percent of elementary school teachers feel very well qualified to teach earth/space science, while better than 80 percent feel well qualified to teach reading; many teachers avoid teaching science; very little time is actually spent teaching science in the elementary school: 19 minutes per day in K-3 and 38 minutes per day in 4-6. While very little science is taught in elementary and middle school, earth/space science is taught at the elementary level in less than half of the states. It was pointed out that science is not generally given high priority by either teachers or school districts, and is certainly not considered on a par with language arts and mathematics. Therefore, in order to teach science to our youth, we must empower our teachers, making them familiar and comfortable with existing materials. In our earlier workshops, several of our teachers taught in classrooms where the majority of the students were Hispanic (over 90 percent). However, few space sciences materials existed in Spanish. Therefore, most of our materials could not be used effectively in the classroom. To address this issue, NASA materials were translated into Spanish and a series of workshops for bilingual classroom teachers from Tucson and surrounding cities was conducted. Our space sciences workshops and our bilingual classroom workshops and how they address the needs of elementary school teachers in Arizona are addressed in detail.

Lebofsky, Larry A.↗
NASA NTRS1992

AVIRIS data and neural networks applied to an urban ecosystem

Urbanization is expanding on every continent. Although urban/industrial areas occupy a small percentage of the total landscape of the earth, their influence extends far beyond their borders, affecting terrestrial, aquatic, and atmospheric systems globally. Yet little has been done to characterize urban ecosystems of their linkages to other systems horizontally or vertically. With remote sensing we now have the tools to characterize, monitor, and model urban landscapes world-wide. However, the remote sensing performed on cities so far has concentrated on land-use patterns as distinct from land-cover or composition. The popular Anderson system is entirely land-use oriented in urban areas. This paper begins with the premise that characterizing the biophysical composition of urban environments is fundamental to understanding urban/industrial ecosystems, and, in turn, supports the modeling of other systems interfacing with urban systems. Further, it is contended that remote sensing is a tool poised to provide the biophysical composition data to characterize urban landscapes.

Ridd, Merrill K.↗