Design And Realization Of An Automated Test-Stand For Variable Capacity Household Compressors

In Switzerland the efficiency of household refrigerators has to be proved by the manufacturer to get the energy label for the devices. The efficiency is tested in the beginning of the lifetime of the fridge and each component, respectively. Especially the compressor might assumedly reach its best performance not before some hours of operation. The exact knowledge about this characteristic is quite important for the manufacturer to optimize the products. Therefore, an automated compressor test stand was designed and built to test variable speed compressors on their evolution of isentropic and volumetric efficiencies. The test stand features three electronic expansion valves to control high and low pressure, and the suction gas temperature of the compressor, automatically. If necessary, an additional heater compensates for the non-isenthalpic pressure drop through the mass flow meter at the discharge of the compressor to enable high suction gas temperatures. Also, the ambient temperature of the device under test is controlled in its separate compartment. The power consumption of the compressor is detected with and without the controller to get additional information. The testing range is 20…200 W cooling capacity with pressures of the refrigerant R600a down to the corresponding evaporation temperature of -35°C and condensing temperatures up to 55°C. The test-stand is equipped with high precision sensors to ensure measurement uncertainties of volumetric and isentropic efficiencies smaller than 5% over the whole range. This paper reports the design of the test stand as well as the control of the system

Dispersive Optical Interface Based on Nanofiber-Trapped Atoms

We dispersively interface an ensemble of one thousand atoms trapped in the evanescent field surrounding a tapered optical nanofiber. This method relies on the azimuthally-asymmetric coupling of the ensemble with the evanescent field of an off-resonant probe beam, transmitted through the nanofiber. The resulting birefringence and dispersion are significant; we observe a phase shift per atom of $\sim$\,1\,mrad at a detuning of six times the natural linewidth, corresponding to an effective resonant optical density per atom of 0.027. Moreover, we utilize this strong dispersion to non-destructively determine the number of atoms.Comment: 4 pages, 4 figure

Optical interface created by laser-cooled atoms trapped in the evanescent field surrounding an optical nanofiber

Trapping and optically interfacing laser-cooled neutral atoms is an essential requirement for their use in advanced quantum technologies. Here we simultaneously realize both of these tasks with cesium atoms interacting with a multi-color evanescent field surrounding an optical nanofiber. The atoms are localized in a one-dimensional optical lattice about 200 nm above the nanofiber surface and can be efficiently interrogated with a resonant light field sent through the nanofiber. Our technique opens the route towards the direct integration of laser-cooled atomic ensembles within fiber networks, an important prerequisite for large scale quantum communication schemes. Moreover, it is ideally suited to the realization of hybrid quantum systems that combine atoms with, e.g., solid state quantum devices

Simulation of a VRF system applied in elcectric buses in Taiwan

Based on test data from an electric bus manufacturer, HVAC systems will consume nearly 30% of the available energy in fully electrically operated public transport buses, which heavily decreases the bus mileage. Therefore, improvements for the bus HVAC system structure are needed. In contrast to conventional electric bus HVAC systems, a VRV (variable-refrigerant-volume) system will be simulated as HVAC system. The compressors provide adequate power depending on the requirements from the different heat exchanger units inside the bus cabin. This system will provide either cooling or heating capacity depending on the needs of the target space. Therefore, the energy consumption of the compressors will be reduced This paper will present a dynamic EES simulation model of a VRV system applied in an electric public transportation bus. Goal of this simulation is, to simulate and design the specifications of the VRV HVAC system with given system performance requirements. The bus model and the simulation results will be described in detail in this publication. This project has been developed in collaboration between the Automotive Research and Testing Center of Taiwan (ARTC) and the University of Applied Sciences in Buchs (NTB)

Education, employment and marriage in long-term survivors of teenage and young adult cancer compared with healthy controls

QUESTIONS UNDER STUDY: Teenage and young adult (TYA) cancer patients are faced with the diagnosis during a challenging period of psychosocial development that may affect social outcomes in the long term. Therefore, we aimed to: (1) determine differences in social outcomes between long-term TYA cancer survivors and healthy controls and (2) identify factors associated with adverse social out-comes. METHODS: We sent a questionnaire to TYA cancer survivors (aged 16-25 years at diagnosis, ≥5 years after diagnosis) registered in the Cancer Registry Zurich and Zug. Information on controls was obtained from the Swiss Health Survey 2012. We assessed educational achievement, employment status, marital status and life partnership (survivors only), and compared these outcomes between survivors and controls. We used logistic regression to identify sociodemo-graphic and cancer-related factors associated with social outcomes. RESULTS: We included 160 TYA cancer survivors and 999 controls. Educational achievement of survivors differed significantly from controls (p = 0.012): more survivors than controls reported upper secondary education (33 vs 27%) and fewer survivors reported uni-versity education (12 vs 21%). No significant differences were found for employment (p = 0.515) and marital status (p = 0.357). The major-ity of survivors (91%) and controls (90%) were employed, and 37% of survivors were married, compared with 41% of controls. There were no cancer-related factors associated with having only basic educa-tion. Unemployment was associated with younger age at diagnosis (odds ratio [OR] 5.3, 95% confidence interval [CI] 1.3-30.8) and self-reported late effects (OR 4.7, 95% CI 1.3-19.5). Survivors of younger age at diagnosis were more likely not to be married (OR 2.7, 95% CI 1.3-5.7) and not to have a life partner (OR 2.3, 95% CI 1.0-5.2). CONCLUSIONS: Our findings indicate that TYA cancer survivors com-pleted applied higher education rather than a university education. Future studies including larger samples of TYA cancer survivors are needed to validate our findings and to explore the reasons for and satisfaction with the observed educational pathway

A Nanofiber-Based Optical Conveyor Belt for Cold Atoms

We demonstrate optical transport of cold cesium atoms over millimeter-scale distances along an optical nanofiber. The atoms are trapped in a one-dimensional optical lattice formed by a two-color evanescent field surrounding the nanofiber, far red- and blue-detuned with respect to the atomic transition. The blue-detuned field is a propagating nanofiber-guided mode while the red-detuned field is a standing-wave mode which leads to the periodic axial confinement of the atoms. Here, this standing wave is used for transporting the atoms along the nanofiber by mutually detuning the two counter-propagating fields which form the standing wave. The performance and limitations of the nanofiber-based transport are evaluated and possible applications are discussed

"Medikamente sind Bomben" - zum Metapherngebrauch von Lungentransplantations-Patienten mit guter oder ungenügender Compliance

Fragestellung: Nach einer Organtransplantation finden komplexe psychologische Verarbeitungsprozesse statt. In der vorliegenden Studie wurde untersucht, welche Metaphern im Zusammenhang mit Transplantationserfahrungen verwendet werden, und ob Unterschiede zwischen Patienten mit guter bzw. ungenügender Compliance im Gebrauch dieser Metaphern bestehen. Methode: 14 lungentransplantierte Patienten wurden in einem halbstrukturierten Interview zu ihren Transplantationserfahrungen befragt. Ihre Compliance wurde von den behandelnden Ärzten eingeschätzt. Die Auswertung der Interviews erfolgte anhand einer Metaphernanalyse, welche Hinweise auf vor- und unbewusste Vorstellungen der Patienten liefert. Die Interraterreliabilität über die Metapherngruppen war Cohen’s Kappa K = 0.8. Ergebnisse: Die Patienten konzeptualisierten ihren Körper, aber auch ihr Selbst als ein “Gefäß”, dass sowohl materielle (z.B. die Lunge) wie immaterielle Objekte (z.B. Gedanken an den Spender, Affekte) enthält. Der wichtigste Unterschied zwischen den Compliance-Gruppen bestand darin, dass Patienten mit ungenügender Compliance eine grössere Distanz zur transplantierten Lunge erlebten. Auch konzeptualisierten sie ihren Körper bzw. ihr Selbst nicht als ein Gefäß, das die Lunge enthält. Diskussion: Die Ergebnisse zeigen, dass gute Compliance mit einer erfolgreichen Organintegration assoziiert ist, welche die Zugehörigkeit der Lunge in einem als Gefäß konzeptualisierten Körper bzw. Selbst umfasst. Patienten mit ungenügender Compliance nehmen die Lunge eher als Fremdkörper wahr. Diese Verarbeitungsprozesse sind teils bewusster, teils vor- und unbewusster Natur