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This paper aims to demonstrate the improved functionality of additive manufacturing technology provided by combining multiple processes for the fabrication of packaged electronics.

This research is focused on the improvement in resolution of conductor deposition methods through experimentation with build parameters. Material dispensing with two different low temperature curing isotropic conductive adhesive materials was characterised for their application in printing each of three different conductor designs, traces, z-axis connections and fine pitch flip chip interconnects. Once optimised, demonstrator size can be minimised within the limitations of the chosen processes and materials.

The proposed method of printing z-axis through layer connections was successful with pillars 2 mm in height and 550 µm in width produced. Dispensing characterisation also resulted in tracks 134 µm in width and 38 µm in height allowing surface mount assembly of 0603 components and thin-shrink small outline packaged integrated circuits. Small 149-µm flip chip interconnects deposited at a 457-µm pitch have also been used for packaging silicon bare die.

This paper presents an improved multifunctional additive manufacturing method to produce fully packaged multilayer electronic systems. It discusses the development of new 3D printed, through layer z-axis connections and the use of a single electrically conductive adhesive material to produce all conductors. This facilitates the surface mount assembly of components directly onto these conductors before stereolithography is used to fully package multiple layers of circuitry in a photopolymer.

The fabrication and characterization of a hydrogel-based conductometric sensor have been carried out. The purpose of this research is to fabricate a small robust hydrogel-based conductometric sensor for real-time monitoring of pH in the physiological range.

A pH-responsive Chitosan/Gelatin composite hydrogel has been used for this purpose. This study reports and analyzes the sensing response obtained from four hydrogel compositions with varying Chitosan/Gelatin ratios. The pH-responsive nature of the hydrogel has been mapped out through volumetric and conductometric tests. An attempt has been made to correlate these characteristics with the physico-chemical nature of the hydrogel through scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction techniques.

The four hydrogel compositions differed on the basis of gel composition ratios; the conductometric analysis results prove that the sensor with the hydrogel composition (Chitosan 2 per cent, Gelatin 7 per cent, ratio 1:2) produces the best pH resolution in the pH range of 4 to 9. The sensing mechanisms and the differences obtained between individual sensor outputs have been discussed in detail. On the basis of this extensive in vitro assessment, it has been concluded that while key pendant functional groups contribute to pH-responsive characteristics of the hydrogel, the overall sensitivity of the sensors gel component to surrounding pH is also determined by the crystalline to amorphous ratio of the hydrogel composite, its interpenetrating cross-linked structure and the relative ratio of the hydrophilic to the pH-sensitive components.

The conductometric sensor results prove that the fabricated sensor with the shortlisted hydrogel composition shows good sensitivity in the physiological pH range (4 to 9) and it has the potential for use in point of care medical devices for diagnostic purposes.

This is the first reported version of the fabrication and testing and analysis/comparison of a hydrogel-based conductometric sensor based on this composition. The work is original and has not been replicated anywhere.

Companies that effectively convey their corporate values, strengths, and experience to an international audience can position themselves to take greater advantage of global opportunities.

For nearly 80 years, the field of macroeconomics has largely been shaped by the aftermath of the Keynesian revolution. Many economists have argued that this revolution and the subsequent internal and external disputes it has sparked have had the unfortunate side effect of crowding out much of what was good in macro-level analysis before it, leading to the dissatisfactory state of macroeconomics we have today. In the search for alternative paths for macroeconomics, I focus on two separate but compatible traditions: monetary disequilibrium (MD) theory and the Austrian business cycle theory (ABCT). I argue that scholars in these traditions employed a far richer micro-theoretic explanation for the business cycle well before Keynes’s General Theory. Unfortunately, their ideas were not united in time to mount a sufficient counterattack to the Keynesian crusade. My goal is to unite the best elements of these two traditions by providing what I believe is the “missing link” that can help connect these alternative paths: free banking theory.

Stress and the military go hand-in-hand, particularly in combat environments. While some personality traits or types weaken relationships between stress and performance, others, such as psychopathy, may strengthen them. In the present chapter, we consider the ramifications of individuals with high levels of psychopathy or psychopathic tendencies in the military with regard to both their own stress and performance and that of those around them. We discuss different reactions to psychological and physical stress, as well as the implications of psychopathic tendencies as they relate to current military issues, including gender, leadership, teamwork, turnover, post-traumatic stress disorder, and suicide. By juxtaposing relevant research findings on stress and psychopathy, we conclude that psychopathic tendencies should have neither uniformly negative nor positive effects on stress and performance in the military. Rather, effects on such individuals and the peripheral others with whom they interact will likely vary greatly depending on numerous factors.

There is a vast amount of literature which identifies characteristics of effective schools and effective classrooms. This paper examines selected studies and their findings and provides an organizing framework which tries to relate these findings to one another and to the school and its environment. A number of implications for school improvement are discussed.

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).