Development of an image converter of radical design

A long term investigation of thin film sensors, monolithic photo-field effect transistors, and epitaxially diffused phototransistors and photodiodes to meet requirements to produce acceptable all solid state, electronically scanned imaging system, led to the production of an advanced engineering model camera which employs a 200,000 element phototransistor array (organized in a matrix of 400 rows by 500 columns) to secure resolution comparable to commercial television. The full investigation is described for the period July 1962 through July 1972, and covers the following broad topics in detail: (1) sensor monoliths; (2) fabrication technology; (3) functional theory; (4) system methodology; and (5) deployment profile. A summary of the work and conclusions are given, along with extensive schematic diagrams of the final solid state imaging system product

Investigation of microbubble/droplet formation in cross-flow and co-flow micro devices

The primary goal of the work presented in this dissertation is to generate microbubbles of a diameter of less than 15μm inside micro channels. In order to achieve this detailed understanding, the facts and limitations behind the generation of microbubbles inside a micro channel are determined from existing literature. The major limitations of the current bubble/droplet generators are found to be the bubble confinement effect, the merging of bubbles, the difficulty in determining bubble diameter and the need for smaller channels to generate smaller bubbles. A device eliminating these drawbacks is conceptualized, and its feasibility is studied using COMSOL® and found to be successful. Based on the findings of the initial studies, prototypes of a new generation of microbubble/droplet generators are developed in this work. This generator utilizes a fused silica tube as the channel carrying the secondary fluid. The micro channel into which the bubbles/droplets are formed is made on a silicon wafer and is sealed using a glass plate. Both cross-flow and co-flow bubble generation devices are analyzed as part of this work. The new generation devices have the advantage of generating unconfined spherical bubbles inside a micro channel while keeping the pressure drop across the channel as low as possible. The new generation cross-flow bubble generator is able to produce bubbles smaller than that possible with existing devices. The cross-flow devices were found to be more efficient in producing microbubbles of smaller diameter in comparison to a similar co-flow device operating under identical conditions. In order to produce smaller microbubbles inside micro channels, a flow focusing technique is introduced in both cross-flow and co-flow devices. Using flow focusing techniques has made it possible to produce microbubbles smaller than that possible without flow focusing. The major parameters that affect bubble formation inside micro channels are determined using a parametric study of both the fluid properties and the geometry of micro channels. A mathematical model is developed to predict the bubble diameter at its detachment from the orifice in a cross-flow device and is validated using experimental data. Surface tension and drag force are found to be the major factors in determining the bubble diameter at detachment. Major achievements of this work are summarized below: 1) A new generation of a microbubble/droplet generator capable of producing unconfined microbubble/droplet is developed in this study. 2) The merging problem of bubbles inside the micro channel immediately after the bubble detaches from orifice is observed for the first time during this study. 3) A microbubble of diameter 11μm is generated in the micro channel of hydraulic diameter 162µm. 4) The bubbly region of bubble formation inside a micro channel is further divided into three in this work: confined region, active region and saturation region. 5) The flow focusing technique inside the cross-flow devices is introduced and studied for the first time during this work. 6) Bubbles of diameter 6µm were produced using the flow focusing technique inside the micro channel of hydraulic diameter 162μm. 7) Circular micro channels were found to be more efficient than straight channels when used in a cross-flow device

Southwest Research Institute assistance to NASA in biomedical areas of the technology utilization program

The activities are reported of the NASA Biomedical Applications Team at Southwest Research Institute between 25 August, 1972 and 15 November, 1973. The program background and methodology are discussed along with the technology applications, and biomedical community impacts

Josephson devices based on topological insulators

Klett R. Josephson devices based on topological insulators. Bielefeld: Universität Bielefeld; 2018

Advances in Heat and Mass Transfer in Micro/Nano Systems

The miniaturization of components in mechanical and electronic equipment has been the driving force for the fast development of micro/nanosystems. Heat and mass transfer are crucial processes in such systems, and they have attracted great interest in recent years. Tremendous effort, in terms of theoretical analyses, experimental measurements, numerical simulation, and practical applications, has been devoted to improve our understanding of complex heat and mass transfer processes and behaviors in such micro/nanosystems. This Special Issue is dedicated to showcasing recent advances in heat and mass transfer in micro- and nanosystems, with particular focus on the development of new models and theories, the employment of new experimental techniques, the adoption of new computational methods, and the design of novel micro/nanodevices. Thirteen articles have been published after peer-review evaluations, and these articles cover a wide spectrum of active research in the frontiers of micro/nanosystems

Journal of Telecommunications and Information Technology, 2017, nr 3

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Bibliography on aircraft fire hazards and safety. Volume 2: Safety. Part 1: Key numbers 1 to 524

Bibliographic citations are presented to describe and define aircraft safety methods, equipment, and criteria. Some of the subjects discussed are: (1) fire and explosion suppression using whiffle balls, (2) ultraviolet flame detecting sensors, (3) evaluation of flame arrestor materials for aircraft fuel systems, (4) crash fire prevention system for supersonic commercial aircraft, and (5) fire suppression for aerospace vehicles

Children in outdoor contexts : affordances and independent mobility in the assessment of environmental child friendliness

According to James J. Gibson, the concept of the affordance refers to the functionally significant properties of the environment, and provides a psychologically relevant means to analyze evolving child-environment relationships. Affordances operationalize the transactional approach. Thus the concept allows researchers to bring the material environment back into the realm of environmental psychology. The framework of ecological perceptual psychology, and in particular the concept of the affordance, was utilized in determining the criteria for child-friendly environments. An assessment model for a child-friendly environment was constructed, which comprises two central criteria for environmental child friendliness: children's possibilities for independent mobility and their opportunities to actualize affordances. By combining various degrees of these two criteria, four hypothetical types of environment were distinguished, Bullerby, Wasteland, Cell, and Glasshouse. The Bullerby type represents a child-friendly environment, as it allows a positive interactive cycle to develop between a child and the environment. In the Bullerby type sufficient possibilities for independent mobility enables to a child to discover environmental affordances. Actualized affordances for their part motivate the child to move around more in the environment, which creates more possibilities for new affordances to become actualized. The empirical results from the study of eight- and nine-year-old children indicated that the developed model was sensitive enough to assess the child friendliness of different communities in Finland and Belarus (Belorussia). All hypothesized environmental types appeared in the data. Each neighborhood had a unique combination of affordances and independent mobility in terms of the model. The Bullerby type of setting abounded in the Finnish communities. The Cell, Wasteland, and Glasshouse types of environment were the most common in the Belorussian data. In general, the proportion of Bullerby-type settings decreased and that of Glasshouse-type settings increased as the degree of urbanization rose. The two-dimensional assessment model presented here could be further developed so that it includes a third dimension such as, for example, the emotional value of affordances for children. At the same time an essential future challenge for ecological perceptual psychology, that of studying the motivational basis of affordances, could be met. As the transactional approach of environmental psychology allows for the integration of children's experiences with the material world, it provides information that can be used in the design and planning of child-friendly environments.reviewe

THE USE OF THE THY-1-YFP-H TRANSGENIC MOUSE STRAIN IN STUDIES OF PERIPHERAL NERVE INJURY

The aim of these studies was to utilise the thy-1-YFP-H transgenic mouse strain to investigate the effects of exogenous agents and the use of nerve conduits on peripheral nerve repair, while developing analysis methods to quantify nerve regeneration in this strain. Using a thy-1-YFP-H mouse common fibular nerve repair model, two potential nerve regeneration enhancing agents [mannose-6-phosphate and EC23] and four conduit designs were assessed. The outcomes of the experiments were measured by analysing whole mount images of the repaired nerves and comparing: axon numbers across the repairs, the proportion of unique axons reaching set distances within the repairs, and the disruption of axons as they entered the repairs. Of the two potential nerve regeneration enhancing agents [administered by pre-soaking the graft tissue and injections into the surrounding tissue] mannose-6-phosphate was shown to significantly reduce the disruption of axons entering the graft, which tied in with results of previous studies on mannose-6-phosphate. EC23 did not appear to have any significant effect upon nerve regeneration, displaying similar results to vehicle treated grafts. Within the conduit studies, both micro-stereolithography produced hollow conduit designs proved successful at enabling regeneration across a short nerve defect - with quantitative results similar to graft repairs - however, axon organisation within those repairs was greatly reduced. The other two conduit designs [aligned fibre filled and hollow nylon-12] were less successful, with limited regeneration occurring across the nerve defect. Through the results of these studies the usefulness of the thy-1-YFP-H transgenic mouse strain in assessing nerve regeneration has been further established. The ability to trace the fate of individual axons through repairs reveals much information that was previously not possible or very difficult to obtain. In addition, the ability to obtain results in only 2-3 weeks makes this model ideal for obtaining useful data quickly for pilot studies

Combining SOA and BPM Technologies for Cross-System Process Automation

This paper summarizes the results of an industry case study that introduced a cross-system business process automation solution based on a combination of SOA and BPM standard technologies (i.e., BPMN, BPEL, WSDL). Besides discussing major weaknesses of the existing, custom-built, solution and comparing them against experiences with the developed prototype, the paper presents a course of action for transforming the current solution into the proposed solution. This includes a general approach, consisting of four distinct steps, as well as specific action items that are to be performed for every step. The discussion also covers language and tool support and challenges arising from the transformation