Reusing salad from salad bars – simulating the effects on product loss,microbial safety and product quality

The goal of this study is to model the effects of reusing salad from salad bars to reduce product loss, while keeping microbial safety and product quality at acceptable levels. We, therefore, expand our previously developed simulation model by incorporating reuse strategies and a quality decay model. The expanded model is used to simulate different salad reuse scenarios and to quantify the consequences to product loss, microbial safety and product quality. With this study, we show an application of a generic approach for the integrated modelling of product loss, microbial safety and product quality. The most cautious scenario consists of reusing salad for only 1 day after the first use and only if the salad originates from a package with a valid best‐before date at the time of reuse (‘minimum reuse of salad with the best‐before date criterion’). This scenario decreases product loss at the salad bar considerably from 37% to 29% (?21%). This considerable benefit occurs almost without causing product loss at the cold storage (increase from 0% to 1%), with only a minimal increase in the number of foetal mortality cases because of Listeria monocytogenes (increase from 11.9 to 12.2 cases per year (+3%)) and hardly any decline in product quality.     

Bauwerksschäden infolge des Erdbebens in Yogyakarta,Java, am 27. Mai 2006

Damage of buildings caused by the Yogyakarta, Java earthquake on May 27, 2006. In May 2006 an earthquake with a magnitude of M_w = 6.3 occurred in Java/Indonesia. Near the epicenter the horizontal ground accelerations were about 2.5–3.0 m/s². However, considerable vertical ground accelerations were also recorded. The paper describes the damage to masonry buildings, reinforced concrete structures and roof structures, found by the authors during a fact‐finding mission in August 2006. Some buildings have been completely demolished by the earthquake. Most of the types of damage observed confirm the importance of the rules generally accepted for earthquake resistant construction. However, in some cases the observed damage and subsequent numerical analysis of the corresponding structure indicate that under certain conditions the vertical ground acceleration component may significantly contribute to the structural loading due to the earthquake and should not be neglected.     

CVT夹紧系统优化

本文详细讨论了对能量损失起主要影响的两个部件.分析了在液压控制中产生的能量损失以及进一步减少损失的可能性.以及变速装置中由于夹紧力产生的机械损.     

Regelung und Steuerung von thermoaktiven Bauteilsystemen (TABS)

Thermoaktive Bauteilsysteme (TABS) haben eine zunehmende Bedeutung bei der energieeffizienten Kühlung und Heizung von Gebäuden, doch ihre Regelung/Steuerung führt in der Praxis oft zu Problemen. Mit dem Ziel, diese Probleme in den Griff zu bekommen, wurde vor fünf Jahren das Forschungsprojekt TABS‐Control gestartet, das zu Beginnd des Jahres 2009 abgeschlossen wurde. Es wurden folgende wesentliche Resultate erarbeitet: Modelle und Simulationsprogramme für TABS; Performance‐Bound‐Berechnungen für die Zonenregelung; eine Auswahl von Regel‐/ Steuer‐Strategien für die Zonenregelung, u. a. mit Lösungen für das automatische Umschalten zwischen Heizen und Kühlen, für den Taktbetrieb der Zonenpumpe und für eine Raumtemperaturregelung; Implementierung von Standardlösungen in einem Gebäudeautomationssystem; Labortests; das neue UBB‐Planungsverfahren (Unknown‐But‐Bounded) zur integrierten Planung von TABS und ihrer Regelung/Steuerung; ein Excel‐Planungstool; Richtlinien zur Wahl der Topologie der hydraulischen Schaltung; eine Methode zur Betriebsoptimierung; eine theoretische Grundlage (UBB‐Ansatz) für das neue integrierte Planungsverfahren und die neuen Regel‐/Steuer‐Strategien; eine Patentanmeldung. Regulation and control of thermally activated building systems (TABS). Thermally activated building systems (TABS) are becoming increasingly important in terms of energy efficient cooling and heating of buildings. In practice, however, regulation and control of such systems often causes problems. Started five years ago with the aim of getting to grips with these problems, the TABS Control research project was completed in early 2009. The project yielded the following results: various models and simulation programs for TABS; performance‐bound calculations for regulating zones; a range of zone regulation/control strategies for planners to choose from, including good solutions for automatic switching between heating and cooling, for pulsed operation of the zone pump and for room temperature control; the implementation of a subset of these strategies as standard solutions in a Siemens building automation system; laboratory tests on these strategies; a new procedure for the integrated planning of TABS and their regulation/control (referred to as UBB planning procedure – Unknown But Bounded); an Excel planning tool; guidelines on selecting the hydraulic switching topology; a method for operation optimization; the theoretical basis for the new integrated planning procedure and the new regulation/ control strategies; a patent application.     

Recoverable Class Loaders for a Fast Restart of Java Applications

We present recoverable class loaders to enable a fast start-up and recovery of Java applications. This is achieved by snapshooting the static state of Java applications namely the class loaders and their associated class objects, which are then recovered during subsequent restarts. Recoverable class loaders are especially useful in the context of mobile applications and mobile services. First, they allow to speed up shutdown and restart of applications for power- and resource-management reasons on resource-restricted mobile devices. Second, services can be much faster rebooted to cure software faults such as memory leaks thereby improving the availability of services. We implemented recoverable class loaders inside the JamVM and the OSGi middleware Oscar. For both cases of use—Java application restart and service recovery—we provide experimental evaluations that show a substantially reduced start-up time from up to 96%.     

现代高性能织造用综框的需求

由于新型织机的发展,对于综框寿命期望日益增加.描述了棕框设计途径,以提高织机的速度并减少综丝的磨损以及综直条的磨损以防止断裂.综框磨损现象是一定会发生的,要做的是减少磨损,使磨损减少到一个可以承受的水平.并且新设计的综直条可以更换,提高了昂贵的综框的使用寿命.     

Do energy efficiency measures really reduce household energy consumption? A difference-in-difference analysis

This study investigates the impact of energy efficiency measures installed through the Carbon Emission Reduction Target (CERT) and the Community Energy Saving Programme (CESP) on domestic gas and total energy consumptions. The recently released National Energy Efficiency Data-Framework (NEED) database is used to examine the changes in domestic gas and total energy consumptions for the dwellings in the sample relative to the changes in gas and total energy consumptions for a comparable control group in the year after installation. The results obtained from this difference-in-difference analysis confirm that observed energy consumption decreases significantly in dwellings following upgrades such as cavity wall insulation, loft insulation and a new efficient boiler. The single most effective energy efficiency measure when installed alone is found to be cavity wall insulation, reducing annual gas consumption by 10.5 % and annual total energy consumption by 8.0 % in the year following installation. Comparing bundles of different energy efficiency measures, we find that dwellings retrofitted with both cavity wall insulation and a new efficient boiler experience the largest reductions in annual gas and total energy consumptions of 13.3 and 13.5 %, respectively. This is followed by a mean annual reduction of 11.9 and 10.5 % in gas and total energy consumptions for dwellings with all three energy efficiency measures installed in the same year. Contrary to expectations, installing cavity wall insulation on its own is found to be more effective in reducing measured energy consumption than combining loft insulation and a new efficient boiler.     

Winglet optimization for a model‐scale wind turbine

A winglet optimization method is developed and tested for a model‐scale wind turbine. The best‐performing winglet shape is obtained by constructing a Kriging surrogate model, which is refined using an infill criterion based on expected improvement. The turbine performance is simulated by solving the incompressible Navier‐Stokes equations, and the turbulent flow is predicted using the Spalart‐Allmaras turbulence model. To validate the simulated performance, experiments are performed in the Norwegian University of Science and Technology wind tunnel. According to the simulations, the optimized winglet increases the turbine power and thrust by 7.8% and 6.3%, respectively. The wind tunnel experiments show that the turbine power increases by 8.9%, while the thrust increases by 7.4%. When introducing more turbulence in the wind tunnel to reduce laminar separation, the turbine power and thrust due to the winglet increases by 10.3% and 14.9%, respectively.