Open Access

A Telecom optical fibers are still being the best transmission medium of digital data and analogue signals for long distance applications. Progress in integrated photonics enables development of photonic chips with new unique properties, circuits of the future, and overcomes current limits in information and communication technologies. The packaging of photonic chips is necessary for taking them out of research laboratories into real implementation in the information and communication technology applications. One important step of packaging is effective coupling of optical radiation between telecom optical fiber with ten microns core dimension and photonic chip optical waveguide with submicron dimensions. For complex photonic chips, it is necessary to couple not one optical fiber but several optical fibers, which are arranged in fiber arrays. In this case, it is necessary to use a 6D positioning system, which allows to optimally adjust the relative position of the photonic chip and the fiber arrays. After setting the optimal relative position of the photonic chip and the fiber array, the process of their fixation follows. One possibility of fixation is gluing with an adhesive in the optical path between the photonic chip and an array of optical fibers with a refractive index close to the refractive index of the optical fiber core. This paper is focused on the experimental test set-up for the temperature characterization of fiber array to photonics chip butt coupling at 1310 nm and 1550 nm wavelengths fixed themselves by UV adhesive in the optical path. The main aims of this works are selection of better adhesive from two types for gluing of photonic chip and fiber array in packaging process of photonics chips and validation of gluing process developing. The coupling and alignment of fiber arrays to photonics chip were done by automated active alignments system and they were fixed themselves by curable epoxy adhesive. Temperature changes of coupling insertion losses are measured and investigated for two different UV adhesives during three temperature cycles from -40 °C to 80 °C in climatic chamber according to Telcordia. Spectral dependence of insertion losses were measured and compared before and after three temperature cycles for 1530 nm to 1570 nm spectral range at room temperature. This work was supported by the Slovak Research and Development Agency under the contracts APVV-17-0662 and SK-AT-20-0017 and by the COST Action “European Network for High Performance Integrated Microwave Photonics” (EUIMWP) CA16220.

Shaolin Wu Fo Dao – die Synthese japanischer und chinesischer Kampfkunst-Lehre auf der Grundlage zen-buddhistischer Theorie und Praxis ist eine neu geschaffene Disziplin. In dieser Fusion verbinden sich wesentliche Elemente aus Budo und Shaolin (-Wudao), deren traditionellen Körper-Geist-Übungen von Kampftechnik (Bu/Wu) und Meditation (Zen/Chan) als originäre Weg- und Heilslehre (Do/Dao) seit jeher der Persönlichkeits- und spirituellen Entwicklung des Ausübenden dienten. Hier nun, in der Überwindung alter Grenzen zwischen japanischer und chinesischer Kampfkunstsysteme („hart“ und „weich“), wurde hier nun erstmaligen ein zusammengewachsenes Kampfkunstsystem kreiert, um die beidseits positiven Wirkungen auf den Menschen zu bündeln und – und das ist das Besondere – sie in den Dienst buddhistischer (Butsu, jap.: Buddha / chin. Fo) Psychologie und Psychotherapie zu stellen. Die Verbindung von Budo mit Shaolin als eigenständiges praktisches Lehrkonzept, allein schon eine „revolutionäre Innovation“, erfährt durch ihren Einsatz als spezielle Methode einer Heilkunst zusätzlich Pioniercharakter in der Behandlung von Leid. Gemeint sind sowohl Ansätze aus der Budopädagogik und speziellen Budotherapie zur Heilung, Linderung oder Prävention von physischen, psychosomatischen und psychischen Krisen, Störungen, Krankheiten, Behinderungen und Leiden, als auch im Sinne des philosophischen und wissenschaftlichen Buddhismus, „das Leid in der Welt zu mindern“, zum Wohle des Menschen, für sein Glück und Frieden zu arbeiten.

Bubble columns are recently used for the humidification of air in water treatment systems and fuel cells. They are well applicable due to their excellent heat and mass transfer and their low technical complexity. To design and operate such devices with high efficiency, the humidification process and the impact of the operating parameters need to be understood to a sufficient degree. To extend this knowledge, we use a refined and novel method to determine the volumetric air–liquid heat and mass transfer coefficients and the humidifier efficiency for various parametric settings. The volumetric transfer coefficients increase with both of the superficial air velocity and the liquid temperature. It is further shown that the decrease of vapor pressure with an increase of the salinity results in a corresponding decrease in the outlet humidity ratio. In contrast to previous studies, liquid heights smaller than 0.1 m are investigated and significant changes in the humidifier efficiency are seen in this range. We present the expected humidifier efficiency with respect to the superficial air velocity and the liquid height in an efficiency chart, such that optimal operating conditions can be determined. Based on this efficiency chart, recommendations for industrial applications as well as future scientific challenges are drawn.

We have demonstrated micromachining of bulk 3C silicon carbide (3C- SiC) wafers by employing 1028nm wavelength femtosecond laser pulses of energy less than 10 nJ directly from a femtosecond laser oscillator, thus eliminating the need for an amplified system and increasing the micromachining speed by more than four orders of magnitude.