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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.

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.

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.

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.

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.