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1 – 10 of 25Knut E. Aasmundtveit, Trym Eggen, Tung Manh and Hoang-Vu Nguyen
This paper aims to demonstrate low-temperature bonding for piezoelectric materials at temperatures well below the relevant Curie temperatures so as to avoid depolarization of the…
Abstract
Purpose
This paper aims to demonstrate low-temperature bonding for piezoelectric materials at temperatures well below the relevant Curie temperatures so as to avoid depolarization of the piezoelectric material during bonding.
Design/methodology/approach
Au-coated test samples of lead zirconate titanate (PZT) are bonded to a WC-based resonant backing layer with In–Bi eutectic material in which the In–Bi metal system is a preform or thin, evaporated layers. The bonded samples are characterized using electrical impedance spectroscopy and cross-section microscopy. The first technique verifies the integrity of polarization and reveals the quality of the bondline in a non-destructive manner, particularly looking for voids and delaminations. The latter technique is destructive but gives more precise information and an overview of the structure.
Findings
Successful low-temperature (115°C) bonding with intact PZT polarization was demonstrated. The bondlines show a layered structure of Au/Au–In intermetallic compounds (with Bi inclusions)/Au, capable of withstanding temperatures as high as 271°C before remelting occurs. For bonded samples using In–Bi preform, repeatable bonds of high quality (very little voiding) were obtained, but the bonding time is long (1 h or more). For bonded samples using evaporated thin films of In–Bi, bonding can be performed in 30 min, but the process needs further optimization to be repeatable.
Originality/value
Low-temperature solid-liquid interdiffusion (SLID) bonding is a novel technique, merging the fields of low-temperature solder bonding with the SLID/transient liquid phase (TLP) approach, which is normally used for much higher temperatures.
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A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps, and…
Abstract
A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps, and sulphur containing materials, etc.
Jason Li‐Ying, Tamara Stucchi, Anne Visholm and Joanna Solvig Jansen
The purpose of this paper is to explain in detail the strategic asset‐seeking OFDIs of Chinese firms in Denmark through a theoretical lens that combines the updated OLI…
Abstract
Purpose
The purpose of this paper is to explain in detail the strategic asset‐seeking OFDIs of Chinese firms in Denmark through a theoretical lens that combines the updated OLI (Ownership, Location, Internalization) paradigm and the internalization theory. Meanwhile, the authors hope to unveil the unique characteristics of firm specific advantages (FSAs, including O and I advantages) and country specific advantages (CSAs, including L advantages).
Design/methodology/approach
The authors chose two case firms that just started investing and a third one that was in the process of preparing investment in Denmark. Primary data were collected by semi‐structured interviews in English at various locations in late 2009 and early 2010. The three Chinese firms in this study share a common primary objective in their strategic orientation of OFDIs. That is to seek strategic assets that are complementary and critical to augment their existing FSAs.
Findings
Rugman stated that strategic asset‐seeking OFDIs are supposed to have high levels of FSAs and CSAs. This study presents a more detailed analysis regarding the O, L and I advantages that Chinese investing firms in Denmark are perceived to possess. It was found that these Chinese investing firms had high levels of Oa and Oi but Ot was largely absent; furthermore, although Lr was obviously appreciated in Denmark, Li presented a mixed picture. The paper also found that internalization advantages were only able to be realized when investing firms were good at utilizing networking and guanxi, which were largely derived from their prior Oi advantages.
Originality/value
Few have analyzed strategic asset‐seeking OFDIs made by emerging markets based on the FSA/CSA matrix that combines the OLI paradigm and the internalization theory. This study pursued this research endeavor by enriching a refined framework that connects the OLI paradigm, which recognizes multiple dimensions of O advantages and an institutional perspective, to the internalization theory, which converts O and I advantages into FSAs and associates L advantages with CSAs.
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This paper aims to determine the important role of acoustic wave devices in sensing applications such as automotive applications, industrial applications and commercial…
Abstract
Purpose
This paper aims to determine the important role of acoustic wave devices in sensing applications such as automotive applications, industrial applications and commercial applications.
Design/methodology/approach
The paper provides a comprehensive overview of acoustic wave technology and highlights an example of one commercial implementation of its technology for sensing application: a commercially available real‐time, online threaded bolt viscosity sensor.
Findings
The commercially available viscosity sensor can be readily applied in field operations or installed directly on the equipment for continuous monitoring of viscosity to enable technicians/mechanics to test the oil in minutes.
Originality/value
The paper introduces a new product for the sensing industry.
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Giovanni Mascali and Vittorio Romano
On the basis of the maximum entropy principle, seeks to formulate a hydrodynamical model for electron transport in GaAs semiconductors, which is free of any fitting parameter.
Abstract
Purpose
On the basis of the maximum entropy principle, seeks to formulate a hydrodynamical model for electron transport in GaAs semiconductors, which is free of any fitting parameter.
Design/methodology/approach
The model considers the conduction band to be described by the Kane dispersion relation and includes both Γ and L valleys. Takes into account electron‐non‐polar optical phonon, electron‐polar optical phonon and electro‐acoustic phonon scattering.
Findings
The set of balance equation of the model forms a quasilinear hyperbolic system and for its numerical integration a recent high‐order shock‐capturing central differencing scheme has been employed.
Originality/value
Presents the results of simulations of n+ ‐n‐n+ GaAs diode and Gunn oscillator.
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This February meeting began in somewhat dramatic fashion—not with the actor's usual injunction to ’break a leg‘ but with the Chairman's announcement that Stuart Briggs, the fourth…
Abstract
This February meeting began in somewhat dramatic fashion—not with the actor's usual injunction to ’break a leg‘ but with the Chairman's announcement that Stuart Briggs, the fourth of the seven presenters, had broken an ankle. It subsequently transpired that he had evidently ’only‘ torn the ligaments, but his presence at the seminar was sorely missed and I know all will wish him a speedy recovery.
Distress signalling according to generally accepted methods and codes has always been the main reason for human survival in sea disasters. Examines the origin of this type of…
Abstract
Distress signalling according to generally accepted methods and codes has always been the main reason for human survival in sea disasters. Examines the origin of this type of communication and its connection to natural senses and channels together with the alphabets, codes and special distress signals used at sea. Reviews the evolution and transformation of the old channels through the introduction of electronic communication, and the opening of some entirely new channels. Compares the different distress channels and makes some proposals concerning new distress signals.
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Advanced robotics R&D in Japan has been selected as a national project to develop robots to work in dangerous environments like nuclear power plants, undersea and fire fighting…
Abstract
A single wafer silicon condenser microphone with a novel single deeply corrugated diaphragm is presented in this paper. The microphone diaphragm with corrugation depth of 100 μm is only 1 mm2 in area, while the open‐circuit sensitivity as high as 9.8 mV/Pa under a bias voltage of 6 V has been obtained. The recorded frequency bandwidth is about 20 kHz. The measurements show reasonable agreements with the theoretical predictions.
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THE Deutsche Versuchsanstalt für Luft‐fahrt—known for short as the D.V.L.—at Berlin‐Adlershof, is the central establishment for aeronautical research in Germany. Hitherto the…
Abstract
THE Deutsche Versuchsanstalt für Luft‐fahrt—known for short as the D.V.L.—at Berlin‐Adlershof, is the central establishment for aeronautical research in Germany. Hitherto the D.V.L. had as its special prerogative the testing of aircraft and aero‐engines for certificates of airworthiness. Since April 1, 1933, the Inspection Department has passed under the authority of the “Reichsamt für Flugsicherung” (Air Security Board), but it has not actually been separated from the D.V.L., continuing to have its premises at the D.V.L. establishment. (Further details of the Inspection Department are given later.)