Using electron gun to deposit CaO on the circumference of Cr:YAG crystal fiber and re-growth by laser heated pedestal growth method, the absorption coefficient of Cr4+ can be achieved to 8.3 cm(-1), which is equivalent to a concentration of 0.015 mol.%; while the total Cr concentration is 0.28 mol.%.

Sonic IR is an emerging, thermal-based, nondestructive evaluation (NDE) technique. Typically a short burst of high power acoustical energy is injected into an object being studied and certain types of defects heat up and is detected using a thermal imaging camera. This inspection technique is very fast, lasting only a few seconds for total inspection time. However due to many uncertainties in the inspection process it has yet to be adopted widely by industry. There are many unknown parameters governing sonic IR, which need to be understood before it becomes a widely used NDE technique. This paper shows that under certain conditions cracks can grow when subjected to the sonic IR technique. We also examine the effects of various experimental parameters on the technique.

Infrared (IR) thermography and, more recently, thermosonics have proven to be viable means of qualitative nondestructive evaluation (NDE). However, structural defects such as cracks observed through thermosonics can only be identified as “hot spots” indicating a general location of a defect without an accurate depiction of the dimensions or shape of the defect. This paper introduces a new technique dubbed Laser Scanning Thermal Probe, LSTP, which combines thermography with the use of heat application in strategic locations to observe the spatial heat flow patterns. LSTP provides the ability to record heat propagation across a defect area with temperature discontinuities forming due to differences in defect thermal diffusivity, thus providing information which can be used to characterize the defect such as crack length.

Confocal and electron microscopic observations of willemite (α-Zn2SiO4) crystalline ware glaze, fired to 1270°C and then aged at 1080°C for 5h, indicated the glaze decomposed as (Zn, Ti, Ca)-rich and (Si, Al, K, Na)-rich regions, from which willemite crystallites and amorphous droplets were formed, respectively. Under the constraint of the glaze thickness, the willemite crystallites further developed into plate-like spherulites, which consists of lath-like crystals growing at the order of [0001]⪢〈101̄0〉>〈21̄1̄0〉 and viable for coalescence over {21̄1̄0} habit plane. The impinged plate-like spherulites formed a flat interface at the early stage of crystallization, but irregular interface in late stage due to weaving, truncation and lateral coalescence of the crystals. The {21̄1̄0}-specific coalescence can be rationalized by Brownian-type motion/rotation of the crystals until parallel epitaxy is reached.

The objectives of this research project are: (1) To design sensor data fusion algorithms that can synergistically combine defect related information from heterogeneous sensors used in gas pipeline inspection for reliably and accurately predicting the condition of the pipe-wall; and (2) To develop efficient data management techniques for signals obtained during multisensor interrogation of a gas pipeline. This final report summarizes all research activities conducted by Rowan University during the project period. This includes the design and development of experimental validation test platforms, the design and development of data fusion algorithms for defect identification and sizing, and finally, the design and development of advanced visualization algorithms for the effective management of data resulting from multi-sensor interrogation of gas transmission pipelines.

This paper presents a technique that can be used to fuse data from multiple sensors that are employed in nondestructive evaluation (NDE) applications, specifically in the in-line inspection of gas transmission pipelines. A radial basis function artificial neural network is used to perform geometric transformations on data obtained from multiple sources. The technique allows the user to define the redundant and complementary information present in the data sets. The efficacy of the algorithm is demonstrated using experimental images obtained from the NDE of a test specimen suite using magnetic flux leakage (MFL), ultrasonic (UT) and thermal imaging methods. The results presented in this paper indicate that neural network based geometric transformation algorithms show considerable promise in multi-sensor data fusion applications.

The purpose of this project was to design, build and test a low cost prototype that transfers compact discs (CDs) from a spindle to a computer based testing station. This will speed up the CD production/testing interface and eliminate the need for manual operation. Along with a heavy product design technical component, the project included a real life educational experience for the four students who got credit for a one year advanced senior project. Various designs were considered and the optimal design (based on cost and performance) was prototyped.

The goals for the project presented are to implement a mobile wireless network of laptop computers for problem solving in engineering courses. Motivation for this project include the existing low cost of hardware and software to realize such a network, the benefits for student learning when computing power is readily available in the classroom, and the poor access and suitability of conventional computer laboratories as a teaching environment. Successful completion of this pilot study will have a high local impact, given our engineering school's desire to make computing resources more widely available to students while containing the cost of the initiative. This same issue is being faced by many engineering schools across the country, and this project can serve as a model of efficient use of computing resources.

In this work, vacuum deposited thin films of lead phthalocyanine (PbPc) were employed as gas sensor to detect mixtures of NO2 and NO. Data collected from sensor responses were used to train a two-stage back-propagation network (BPN) for the determination of the gas mixture composition. The success rate for the two-stage BPN in identifying categories of gas mixture approaches 100%. The maximum error for the two-stage BPN in predicting NO concentration in a gas mixture with fixed NO2 concentration is 14.7%.

There has been a rapid growth in interest to integrate technology into the engineering curriculum, both to extend the reach and effectiveness of teaching and learning, and in response to industry needs. We have conducted a survey of engineering faculty at the eight coalition universities to identify the training needs and present levels of experience with various technologies. The results of that survey are presented in this paper, with an emphasis on the variations between faculty rank and the institutions' emphasis on teaching and research. The results showed that, as a coalition, there is little variation between faculty rank (Assistant, Associate, or Full Professor) with regard to either (1) faculty skill level, (2) current use of various technologies, and (3) faculty willingness to attend technology workshops. When the data was further segregated according to whether each institution's main mission is research or undergraduate teaching, the results were unchanged for faculty skill level and current use of each technology. The only observed difference between research and teaching institutions was that a higher percentage of Associate and Full Professors at teaching institutions are willing to attend technology workshops, while Assistant Professors are equally as willing as their peers at research institutions.

In this work, vacuum deposited thin films of PbPc, NiPc, VOPc, TiOPc and CoPc were employed as gas sensor to detect NO2 and NO. Data collected from sensor responses were used to train a back-propagation network (BPN) for identifying the gas species and quantifying its concentration. The results show that among the metallophthalocyanines tested, PbPc and NiPc have better sensing characteristics towards NO2 and NO. In BPN training, maximum error occurs for data collected by the TiOPc sensor, and minimum error occurs for array of PbPc and NiPc sensors. In the concentration prediction of NO or NO2, the maximum predicted error is 6.94%. When Two-Stage BPN or Single-Stage BPN was use to identify and quantify a single gas (NO2 or NO), the accuracy of recognition approaches 100% and the maximum error for concentration prediction is 7.45%.

BACKGROUNDThe delayed allograft rejection in C6-deficient PVG C6- rats compared with normal PVG rats has been attributed to the lack of alloantibody activation of the membrane attack complex of complement. As T cells alone have been shown to effect graft rejection, we examined T-cell responses in PVG C6- rats.METHODSThe cellular infiltrate and its mRNA for cytokines and effector molecules in DA heart allografts to PVG and PVG C6- rats was compared by immunoperoxidase staining and semiquantitative reverse transcriptase polymerase chain reaction. The ability of pure populations of T cells or alloantibody to mediate DA heart graft rejection in irradiated (750 rads) PVG and PVG C6- rats was also compared.RESULTSThe median rejection time of DA heart allografts was 8 days in PVG rats and 17.5 days in PVG C6-. PVG C6- rats sensitized to DA by two skin grafts rejected DA heart grafts in 5-6 days. CD3+, CD4+, CD8+, interleukin-2 receptor-positive T cell, macrophage, and natural killer cell infiltration, as well as class II major histocompatibility complex and intercellular adhesion molecule-1 up-regulation, in grafts was similar in naive PVG and PVG C6- rats. mRNA for T helper 1 cytokine interleukin-2, interferon-gamma, tumor necrosis factor-beta, macrophage molecules tumor necrosis factor-alpha, and inducible nitric oxide synthase, as well as cytotoxic T-cell effector molecules perforin and granzyme A and B, were found to be the same in the grafts from both naive PVG and naive PVG C6- rats. Thus, there appeared to be no difference in the T-cell effector response between the PVG and PVG C6- groups. There were higher alloantibody titers in PVG C6- rats than in PVG hosts. Irradiation ablated rejection and alloantibody responses and reconstitution with naive T cells alone restored rejection in both PVG and PVG C6- rats. Irradiated rats given serum from PVG rats that had rejected DA grafts did not effect rejection of DA grafts even if given naive T cells. Sensitized T cells restored second set.CONCLUSIONSPVG C6- rats have normal T-cell responses and can mediate allograft rejection in the absence of alloantibody. The failure of PVG C6- to reject allografts rapidly may be a result of the poor clearance of alloantisera leading to enhancement of graft survival rather than a critical role for complement and membrane attack complex in acute rejection.

Anti-CD4 mAb-induced tolerance to transplanted tissues has been proposed as due to down-regulation of Thl cells by preferential induction of Th2 cytokines, especially IL-4. This study examined the role of CD4+ cells and cytokines in tolerance to fully allogeneic PVG strain heterotopic cardiac allografts induced in naive DA rats by treatment with MRC Ox38, a nondepleting anti-CD4 mAb. All grafts survived >100 days but had a minor mononuclear cell infiltrate that increased mRNA for the Thl cytokines IL-2, IFN-gamma, and TNF-beta, but not for Th2 cytokines IL-4 and IL-6 or the cytolytic molecules perforin and granzyme A. These hosts accepted PVG skin grafts but rejected third-party grafts, which were not blocked by anti-IL-4 mAb. Cells from these tolerant hosts proliferated in MLC and produced IL-2, IFN-gamma, and IL-4 at levels equivalent to naive cells. Unfractionated and CD4+ T cells, but not CD8+ T cells, transferred specific tolerance to irradiated heart grafted hosts and inhibited reconstitution of rejection by cotransferred naive cells. This transfer of tolerance was associated with normal induction of IL-2 and delayed induction of IFN-gamma, but not with increased IL-4 or IL-10 mRNA. Transfer of tolerance was also not inhibited by anti-IL-4 mAb. This study demonstrated that tolerance induced by a nondepleting anti-CD4 mAb is maintained by a CD4+ suppressor T cell that is not associated with preferential induction of Th2 cytokines or the need for IL-4; nor is it associated with an inability to induce Th1 cytokines or anergy.