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Essential elements of a housing intervention designed to serve people who are homeless or risk becoming homeless, have severe mental illness, and may have a substance use disorder are described and summarized in a logic model. Characteristics of the target population, the community and the service system are examined, and how this program serves to address the issues. The effectiveness of this intervention appears to be the result of the organizational characteristics. The organizational structure and climate provide: (a) integrated services under one “umbrella”; (b) flexible, responsive service delivery; and (c) a treatment philosophy which builds on the strengths of residents through effective staff-resident relationships.

A magnetic microrheometer has been designed to characterize the local viscosity of liquid-applied coatings in situ during solidification. The apparatus includes NdFeB magnets mounted on computer-controlled micropositioners for the manipulation of ∼1 μm diameter superparamagnetic particles in the coating. Magnetic field gradients at 20-70 T/m are generated by changing magnet size and the gap distance between the magnets. A specimen stage located between two magnets is outfitted with a heater and channels to control process conditions (temperature and air flow), and a digital optical microscope lens above the stage is used to monitor the probe particle position. Validation studies with glycerol and polyimide precursor solution showed that microrheometry results match traditional bulk rheometry within an error of 5%. The viscosities of polyvinyl alcohol (PVA) solution and polyimide precursor solution coatings were measured at different shear rates (0.01-5 s(-1)) by adjusting the magnetic field gradient. The effect of proximity to the substrate on the particle motion was characterized and compared with theoretical predictions. The magnetic microrheometer was used to characterize the time-viscosity profile of PVA coatings during drying at several temperatures. The viscosity range measured by the apparatus was 0.1-20 Pa s during drying of coatings at temperatures between room temperature and 80 °C.

Drawing from a curricular model proposed in a recent report from educators in the UK, this article examines the need to educate US engineering students in intellectual property concepts through partnerships between law students and undergraduate engineering students [1]. The educational vehicle that is the focus of this article is the engineering senior capstone design project. In the proposed pedagogical model, law students studying intellectual property will take on the role of advisors to engineering students (their clients) while the latter group endeavors to develop an engineering solution to a real world problem. This article also seeks to identify and address concerns of licensing authorities and professional associations that may arise as a result of implementation of the model.

Polymer-dispersed liquid crystal (PDLC) is a composite material that consists of sub micron-size droplets of liquid crystalline (lc) material dispersed in a polymer matrix. A device is usually assembled by sandwiching PDLC between ITO-coated glass plates. The electro optical properties of such a device can be controlled by the application of electric fields; the device acts as a “switch” for the transmission of light. The transmission of light through the device can be controlled between almost zero and 100% by applying ac electric fields. The dielectric properties of the lc and polymer, shape and size distribution of the lc droplets in the PDLC, amplitude and frequency of the applied electric field are among the important parameters for optimizing the performance of such a device. We have investigated the optical properties of PDLC devices fabricated by using several different phase-separation techniques and different lc/polymer materials. We present results for the switching characteristics of these devices as functions of applied electric fields and the size-distribution of the lc droplets. We also present results that reinforce the influence of the interfacial charges on the optical properties of the PDLC devices.

This paper reports three aspects of an ongoing building archeology project at the MacPheadris-Warner House (ca. 1716–23) in Portsmouth, N.H., U.S.A. One is the use of a portable moisture meter to map rising damp levels and areas of water infiltration through brickwork. The second is the mapping of crack patterns and other defects on exterior elevations. We will also refer to a second site, the Juliette Gordon Low House in Savannah, Georgia, in discussing the problem of crack mapping. The third project is an ongoing attempt to replicate a shell lime mortar.

A recurring procedural flaw exists in many textbook treatments of approximate methods for the analysis of rectangular, rigid frames under uniform vertical loading. The majority of textbooks surveyed cite an inappropriate assumption regarding the approximate analysis of vertically loaded frames which leads to erroneous solutions. One of the prevalent assumptions, which leads to incorrect shear forces and bending moments in columns, is that a negligible axial force exists in each girder. A more appropriate first-pass substitute might be to assume that inflection points occur in each column at mid-height, or at hinged supports of column bases at ground level. Using a simple, uniformly loaded, symmetric, rectangular frame as an example (this frame appears frequently in textbook examples), a trial revised set of assumptions produces an improved approximate solution. Work is proceeding to develop a fully tested, revised method of approximate structural analysis for vertically loaded rectangular frames.

Analysis of the interaction between a precast wall cladding panel and a reinforced concrete frame under linear static and dynamics forces has been performed. Two computer programs (LDYN and LSTAT) were written to evaluate the effects on the lateral displacements and dynamic characteristics of a moment resisting frame when the cladding is incorporated into the analysis as a structural component. The data indicates a significant change in lateral displacement, natural frequency, member force distribution and connector forces when compared with a frame neglecting the structural characteristics of the cladding.

The meteorology equipment carried by the Viking landers was intended to measure atmospheric temperature, wind speed, wind direction, and pressure. During the summer months, the winds were a few meters per second, with a complex hodograph and the Lander-1 site, dominated by counterclockwise turning of the wind, and a simpler hodograph at the Lander-2 site, marked by clockwise turning of the wind. With advancing season, the repetitive wind pattern began to break down, and protracted northeasterly winds were recorded on several occasions (some of which are associated with lower than normal temperatures). Examples are given of wind and temperature traces over short periods, illustrating the effects of convection, static stability, and lander interference. A theoretical argument, based on the horizontal scale dictated by heating of slopes and on vertical mixing of momentum, is presented to explain the different sense of wind rotation at the two lander sites.

A study was done on the macroscopic effects on a frame's behavior when cladding panels are structurally incorporated into the analysis. The following is a report on the effects of cladding panels on the natural vibration frequencies of a structural frame. The microscopic effects of the panel's inclusion, i.e. the stresses internal to the panel itself, are not studied. A two story, one bay frame with a single cladding panel at mid-height was used throughout the analysis. The cladding panel was represented by five different models; 4 noded, 16 DOF (degrees-of-freedom) rectangular finite element, 4 noded, 12 DOF rectangular finite element, 4 and 8 noded quadrilateral plane stress elements with only two translational DOF at each node, and an analogous frame model. To analyze the effect of discretization on the results with each model, the cladding panel was subdivided into meshes varying from 1 to 16 elements. The results of each model with the various meshes were compared. Frame behavior as a function of panel height was also studied. Ratios of panel height to story height of 30%, 50%, 70% and 90% were used. The degree of fixity of the elements connecting the panel to the frame varied from a pinned connection to full fixity. The data indicates that incorporation of cladding panels results in a dramatic reduction in a structure's natural periods of vibration.

The results from the meteorology instruments on the Viking 1 lander are presented for the first 20 sols of operation. The daily patterns of temperature, wind, and pressure have been highly consistent during the period. Hence, these have been assembled into 20-sol composites and analyzed harmonically. Maximum temperature was 241.8 degrees K and minimum 187.2 degrees K. The composite wind vector has a mean diurnal magnitude of 2.4 meters per second with prevailing wind from the south and counterclockwise diurnal rotation. Pressure exhibits diurnal and semidiurnal oscillations. The diurnal is ascribed to a combination of effects, and the semidiurnal appears to be the solar semidiurnal tide. Similarities to Earth are discussed. A major finding is a continual secular decrease in diurnal mean pressure. This is ascribed to carbon dioxide deposition at the south polar cap.

Presented in this paper is an interactive computer program which will aid the engineer in selecting the trial section properties of a column for the iterative design and analysis process. An algorithm is developed around the effective length factor (K) and the end restraint factor (ψ) for an unbraced frame. The output is a table of values of the ratio of the column moment of inertia to the beam moment of inertia (IR) as a function of the effective length factor (K). The program is written in standard Fortran.

Daily mean atmospheric pressures at the two Viking landers are presented for slightly more than a Martian year. The seasonal variation of pressure owing to exchange of CO2 with the polar caps is quite evident and contradicts, in part, earlier theoretical results. Day-to-day variations are the result of passage of synoptic-scale high and low pressure systems and are an important clue to the general circulation of the atmosphere. The effects of global dust storms on the general circulation and on the diurnal variation of pressure are detected and interpreted.

The development of efficient missile systems requires more precise measurements of the winds and wind shears within the atmosphere than are provided by current wind-sounding methods. The gross smoothing inherent in balloon soundings effectively filters out the small-scale wind variations which are of considerable importance to missile response problems. A method in which the detailed structure of the vertical wind profile is determined from photogrammetric measurements of the successive positions of a smoke trail left by a vertically rising missile has been developed and applied by the Langley Research Center of the NASA. The method is described in this paper and its accuracy is discussed. Results in the form of wind profiles for several measurements are presented. Particular attention is given to the continuous and random nature of the wind disturbances as a function of altitude and to the implication of these disturbances characteristic to missile responses.

The purposes, procedures, and nature of the planned meteorology experiment of Viking, 1976 are described. The elements to be measured are pressure, temperature, wind speed, wind direction, and water vapor content of the atmosphere. The interactions with other Viking experiments are outlined and candidate sensors are described.

Eight ARCAS meteorological rockets were fired from Wallops Island (38N, 75W) before, during and after the total solar eclipse of 7 March 1970. Detailed temperature and wind data were acquired to an altitude of about 65 km. Pressures and densities were derived by hydrostatic integration of the corrected temperature profiles. A time-height cross section of the temperature data (smoothed to suppress small-scale detail) shows significant cooling mainly in the layer 40–60 km. Maximum amplitude of the temperature perturbation is about 9K, near 50 km. Maximum pressure variation, amounting to a decrease of at least 7%, occurred about one scale height higher, near 58 km. The ARCAS wind observations are independent of the thermodynamic measurements; a time-height analysis of the winds shows a large amplification of the meridional flow, which is found to be consistent with the observed pressure changes. Derivatives in the perturbation equation of motion are evaluated with the aid of a space-time transformat...

Methods are developed for determining the contribution by each harmonic wave component to the geostrophic kinetic energy of meridional and zonal motion, and to the geostrophic fluxes of angular momentum and enthalpy. Evaluations are carried out for each day of January 1951 for selected latitudes and pressure surfaces and the resulting spectral distributions discussed. Salient features are large spatial and temporal variations of the energy spectra and unexpectedly large contributions by the lower wave numbers to the fluxes of momentum and heat.

The relatively large amount of rocketsonde data now available for selected stations together with representative estimates of the solar radiation corrections has been utilized to establish the phases and amplitudes of the diurnal temperature oscillations from 30 to 60 km. Once the magnitude of the solar radiation errors and the diurnal temperature oscillations are established, these values are used to obtain new estimates of the actual mean temperatures for each calendar month.

The variation in winds and resulting variations in wind loads on vertically launched vehicles for different worldwide geographical areas are investigated. Methods of determining possible alternate launch sites that offer distinct windwise advantages over presently used sites are discussed; reductions of 50 per cent or more in statistically determined peak winds or in statistical values of wind shears at critical altitudes may be realized. Since peak winds and maximum shears are recognized parameters of wind-induced loading, the variations in peak loads that are expected at different launch sites should reflect significant changes in wind environment with geographical regions. For some particular vehicles, variation of a single parameter, such as maximum wind speed, will produce large differences in computed load histories. An interesting disclosure of subjecting a simulated large liquid-propellant vehicle to various wind inputs is that the peaks of the load histories appear more strongly related ...

Atmospheric temperature and wind data before, during and after solar eclipse of 7 March 1970, using ARCAS meteorological rockets

The results from the meteorology instruments on the Viking 1 lander are presented for the first 4 sols of operation. The instruments are working satisfactorily. Temperatures fluctuated from a low of 188 degrees K to an estimated maximum of 244 degrees K. The mean pressure is 7.65 millibars with a diurnal variation of amplitude 0.1 millibar. Wind speeds averaged over several minutes have ranged from essentially calm to 9 meters per second. Wind directions have exhibited a remarkable regularity which may be associated with nocturnal downslope winds and gravitational oscillations, or to tidal effects of the diurnal pressure wave, or to both.

Early results from the meteorological instruments on the Viking 2 lander are presented. As on lander 1, the daily patterns of temperature, wind, and pressure have been highly repetitive during the early summer period. The average daily maximum temperature was 241 degrees K and the diurnal minimum was 191 degrees K. The wind has a vector mean of 0.7 meter per second from the southeast with a diurnal amplitude of 3 meters per second. Pressure exhibits both diurnal and semidiurnal oscillations, although of substantially smaller amplitude than those of lander 1. Departures from the repetitive diurnal patterns begin to appear on sol 37.

The daily mean pressures at two locations on Mars, observed over 57% of a Martian year, reveal a semiannual oscillation with a peak-to-peak difference that is 26% of the mean pressure. This intrinsically Martian phenomenon is caused by exchange of CO2 between the atmosphere and the winter polar caps. Evidence is presented that the difference in pressure at the two landers varies with season and that the seasonal variation is not completely removed by hydrostatic correction for the difference in elevation. The mass CO2 sublimed from the south polar cap is estimated to be greater than or equal to 7.9 x 10 to the 12th metric tons, corresponding to a mean thickness of solid CO2 over the maximum extent of that cap of greater than or equal to 23 cm. Estimates are formed of the meridonal wind speed conveying gas out of the dissipating cap and the associated zonal geostrophic wind, both averaged over longitude. The results are approximately 2.3 m/sec and 14 m/sec, respectively.

Meteorological instrumentation aboard the Viking Mars Landers measures wind, temperature, and pressure. Two global dust storms occurred during northern autumn and winter, observed both by the orbiters and by the landers. The meteorological data from the landers has been analyzed for the period just before first storm arrival to just after second storm arrival, with the objectives of defining the meteorological phenomena during the storm period, determining those associated with storm and dust arrival, and evaluating the effects on synoptic conditions and the general circulation. Times of dust arrival over the sites could be defined fairly closely from optical and pressure (solar tide) data, and dust arrival was also accompanied by changes in diurnal temperature range, temperature maxima, and temperature minima. The arrivals of the storms at Viking Lander 1 were accompanied by significant increases in wind speed and pressure. No such changes were observed at Viking Lander 2. It is possible that surface material could have been raised locally at Viking Lander 1. Throughout the period except for the time following the second dust storm the synoptic picture at Viking Lander 2 was one of eastward moving cyclonic and anticyclonic systems. These disappeared following the second storm, a phenomenon which may be related to the storm.

Analysis of a 12-sol period of wind speed, wind direction, temperature, pressure, and optical depth at the Viking Lander 2 site presents the first in situ evidence of high- and low-pressure systems, complete with fronts, on the surface of Mars. The discovery of these systems in the Lander data occurred while analyzing a period during which the north polar hood was advected over the site at midday, dramatically decreasing the surface illumination and surface-to-atmospheric heat flux. This obscuration immediately preceded a global dust storm in the southern hemisphere and low latitudes of the northern hemisphere. The direct effects of the dust storm, reached 48 N, the Lander 2 latitude, later more gradually than they reached the 22 deg N latitude of Lander 1. The system responsible for the polar hood passages is a major disturbance, and it appears that radiational damping is inadequate to stop strong frontal formation. The front analyzed is characteristic of a repetitive series of systems that pass roughly every 3.3 sols. These systems are similar to those predicted by theoretical analyses and by general circulation modeling of the Martian atmosphere and those observed in laboratory experiments.