Order-disorder transitions in a sheared many body system

Motivated by experiments on sheared suspensions that show a transition between ordered and disordered phases, we here study the long-time behavior of a sheared and overdamped 2-d system of particles interacting by repulsive forces. As a function of interaction strength and shear rate we find transitions between phases with vanishing and large single-particle diffusion. In the phases with vanishing single-particle diffusion, the system evolves towards regular lattices, usually on very slow time scales. Different lattices can be approached, depending on interaction strength and forcing amplitude. The disordered state appears in parameter regions where the regular lattices are unstable. Correlation functions between the particles reveal the formation of shear bands. In contrast to single particle densities, the spatially resolved two-particle correlation functions vary with time and allow to determine the phase within a period. As in the case of the suspensions, motion in the state with low diffusivity is essentially reversible, whereas in the state with strong diffusion it is not.Comment: 12 pages, 13 figures; Supplemental Movies: https://youtu.be/oFcrWo9Vs6E, https://youtu.be/tcowb7o05JQ, https://youtu.be/GkEUwycn7V4, https://youtu.be/k-XCo8CWFU

Potential of additively manufactured particle damped compressor blades: A literature review

The high-cycle fatigue of compressors significantly impacts the lifetime of aircraft engines. Excitations in resonance lead to early blade fractures; therefore, vibration reduction measures for blades must be taken. Additively manufactured particle dampers are a suitable measure to suppress vibrations. The focus of this paper is to analyze the applications of additively manufactured particle dampers in compressor blades through a literature review. The design requirements, previous vibration reduction measures for compressor blades and properties of additively manufactured particle dampers are investigated in three studies. In order to evaluate the application of additively manufactured particle dampers in compressor blades, the findings are compared and research demand is derived. The main requirements on compressor blades are stiffness, vibration reduction and wear-resistance. Recent vibration reduction measures are focused on friction dampers. To optimize damping multiple vibration suppression measures shall be used. Few studies exist for additively manufactured particle dampers and some prove their damping improvement in compressor blades. Due to the complicated operation conditions, further studies are needed, which are listed to give researchers an approach for further steps

Self-Adaptive Performance Monitoring for Component-Based Software Systems

Effective monitoring of a software system’s runtime behavior is necessary to evaluate the compliance of performance objectives. This thesis has emerged in the context of the Kieker framework addressing application performance monitoring. The contribution includes a self-adaptive performance monitoring approach allowing for dynamic adaptation of the monitoring coverage at runtime. The monitoring data includes performance measures such as throughput and response time statistics, the utilization of system resources, as well as the inter- and intra-component control flow. Based on this data, performance anomaly scores are computed using time series analysis and clustering methods. The self-adaptive performance monitoring approach reduces the business-critical failure diagnosis time, as it saves time-consuming manual debugging activities. The approach and its underlying anomaly scores are extensively evaluated in lab experiments

A Combined Cleaning and Disinfection Measure to Decontaminate Tire Treads from Tomato Brown Rugose Fruit Virus

Mechanically transmissible and stable viruses such as tobamoviruses, which include Tobamovirus fructirugosum (syn. tomato brown rugose fruit virus (ToBRFV), will continue to pose major challenges for farmers. Consequently, holistic hygiene concepts are being implemented to prevent the introduction and spread of these viruses. The decontamination of tires and castors was previously a weak point in many industrial hygiene concepts. For this reason, the ProfilGate clean-off zone was tested in combination with the disinfectant MENNO Florades for the decontamination of ToBRFV-contaminated tires. In total, 478 tire segments were sampled to evaluate the contamination of ToBRFV and the following decontamination of the tires. This treatment reliably removed high (4.5 µg/cm2), medium (0.45 µg/cm2), and low concentrations (0.045 µg/cm2) of ToBRFV from the tires, as shown by a bioassay. The reduction in necrotic local lesions on susceptible indicator plants N. tabacum cv. Xanthi NN was between 91.9 and 97.6%. The reduction in ToBRFV contamination largely depended on the length of the rollover distance, i.e., the number of tire rotations. For transport trolleys with polyamide and rubber tires, depletions of 97.4 and 97.6%, respectively, was determined after 16 rotations. For transport wagons with tires twice the size and polyurethane tread, the depletion was still at least 91% after eight wheel turns. Even in the case of gross soiling of the tires, the mean reduction from the different tread materials was 80.9 to 98.9%. Subsequent analysis of the clean-off zone revealed that ToBRFV did not accumulate, even when the contaminated tires were driven over several times, but was safely inactivated completely in the disinfectant solution. This provides growers with an effective tool for preventing the introduction and spread of ToBRFV.This research was funded by HEUTE Maschinenfabrik GmbH & Co KG and MENNO Chemie Vertrieb GmbH.HEUTE Maschinenfabrik GmbH & Co KGMENNO Chemie Vertrieb GmbHPeer Reviewe

Risk‐ och exponeringsreducering i ett tillverkande företag

The foundation of this thesis has been to investigate the possibilities of giving Stena Aluminium, a company recycling aluminium, increased control to regulate and steer the risk they are taking when exposing raw material and finished goods. Stena Aluminium wants to minimize the risk of losses on raw material and finished goods when prices change. This is a large problem for instance when raw material is stored a long time thus making it sensitive to volatile prices. Today, Stena Aluminium bases their operations on the experience and tested methods that exists in the company and tried methods without actual possibilities for controlled optimization and regulation. After an evaluation of today’s conditions we arrived at the conclusion that we need to create a model to be able to systematically approach the problem of risk and exposure. To investigate this, we have put forward some questions at issue that initially control if Stena Aluminium’s forecasting is sufficiently good enough to base subsequent investigations on. The basis of a low level of exposure is that the forecasts have a forecasting error as small as possible. To measure how good Stena Aluminium’s forecasts are we tried to forecast the actual result ourselves using quantitative methods. To sharpen our forecasting we classified their articles according to the demand pattern, making it possible to choose the best forecasting method for respective class. We concluded that Stena Aluminium’s own qualitative way of forecasting is to be preferred, as they actually have a very good take on the demand a month in advance, but that quantitative forecasting could be used as a complement to level out the quality of the forecasts. When having an almost deterministic demand, uncertainties in time are bigger than uncertainties in quantity. The next step was so explore the possibility of affecting the exposure of raw material through optimizing of purchasing. We reduced the problem to a minimization of the total cost by introducing concepts like carrying cost, ordering cost and an easy way to vary the carrying cost on the basis of volatility of the price. Optimal purchasing lots were then established by using a cost optimizing algorithm on varying demand. We also tested a way of taking forward prices into accord by varying the carrying cost, making it possible to take advantage of low price. A significant reduction of the total cost was, however, not found. We also evaluated different ways of calculating safety time. To systematically establish appropriate safety times for finished goods we recommend Stena Aluminium to register their customers´ tendencies to change the delivery date of their orders and on the basis of this calculate the safety times. We compel Stena Aluminium to register more data to be able to have enough information to evaluate all parts of the material management in a thorough way. This will help in future performance improving projects

Decontamination of Tomato Brown Rugose Fruit Virus-Contaminated Shoe Soles under Practical Conditions

Due to its global spread, easy mechanical transmissibility inside greenhouses, and detrimental effects on marketability, Tomato brown rugose fruit virus (ToBRFV) is considered to be one of the biggest threats to tomato production. Regarding such crop epidemics, it is essential to identify all conceivable transmission routes and to interrupt them with effective decontamination strategies. We analyzed the potential efficacy of reliable shoe sole cleaning in combination with a disinfection measure. For this purpose, first, a suspension test was undertaken that involved applying different disinfectants to an infected plant homogenate. This was followed by a simulated carrier test. Finally, shoe-sole decontamination was tested under practical conditions. The extent of decontamination was determined by bioassays of the infectivity of the initial load remaining after treatment. Thereby, necrotic local lesions on the susceptible indicator plant Nicotiana tabacum cv. Xanthi NN were counted. Recommendations for practical applications, based on suspension or simulated carrier tests, are limited in their applicability, since very short contact times between ToBRFV and disinfectants reduce efficacy. Under practical conditions, the approved disinfectant MENNO Florades was able to achieve complete inactivation of the virus in the disinfection mat following mechanical depletion from the shoe soles.Peer Reviewe

Cleaning of Tomato brown rugose fruit virus (ToBRFV) from Contaminated Clothing of Greenhouse Employees

The highly infectious Tomato brown rugose fruit virus (ToBRFV) is a new viral threat to tomato production worldwide. In production, the very easy mechanical transmissibility combined with the high resistance in vitro is of great concern. We tested: (i) whether household cleaning products, commercial agricultural detergents, and an authorized plant protectant are suitable for cleaning contaminated clothing, and (ii) whether infectious viruses remain in the resulting cleaning water. The evaluation of the sanitation effect was performed using bioassays, by counting ToBRFV-associated necrotic local lesions on Nicotiana tabacum cv. Xanthi NN. For this purpose, leaves were mechanically inoculated with treated fabrics and cleaning solutions which would normally be discharged to the sewer system. The detergents Fadex H+ (FH) and Menno Hortisept Clean Plus, as well as the disinfectant Menno Florades (MF), led to an almost complete removal of ToBRFV from contaminated fabrics, corresponding to a reduction in local lesions by 99.94–99.96%. In contrast, common household cleaning products (Spee ActivGel (SAG), Vanish Oxi Action Gel (VO) did not effectively remove the pathogen from the fabric, where the reduction was 45.1% and 89.7%, respectively. In particular, cleaning solutions after the use of household cleaners were highly contaminated with ToBRFV. After a 16-h treatment with the disinfectant MF, infectious ToBRFV was no longer present in VO, FH, and MF cleaning solutions, as demonstrated by extensive bioassays.German Federal Ministry of Food and AgricultureDeutsche Forschungsgemeinschaft (DFG)Open Access Publication Fund of Humboldt-Universität zu BerlinPeer Reviewe

High magnitude and rapid incision from river capture: Rhine River, Switzerland

Landscape evolution is controlled by the development and organization of drainage basins. As a landscape evolves, drainage reorganization events can occur via river capture or piracy, whereby one river basin grows at the expense of another. The river downstream of a capture location will generate a transient topographic response as the added water discharge increases sediment transport and erosion efficiency. This erosional response will propagate upstream through both the captured and original river basins. Here we focus on quantifying the impact of drainage reorganization along the Rhine/Aare River system (~45,000 km 2 ) during the late Pliocene/early Pleistocene, where gravel remnants indicate total incision of ~650 m during the last ~4.2 Myr in the region of the recent Aare‐Rhine confluence. We develop a numerical model of drainage capture to quantify the range of possible magnitudes of erosion and the transient river response resulting from the reorganization of the Rhine River. The model accounts for both fluvial incision and sediment transport. Our model estimates 400–800 m of river elevation change (lowering profiles) during the last ~4 Myr due to river capture events, providing an important component to the recent exhumation budget of the Swiss Alpine Foreland. The model indicates a rapid response to capture events (re‐equilibration timescale of ~1 Myr). The predicted incision magnitudes are consistent with incision measured from the elevation of Pliocene and early Pleistocene river gravels, suggesting that across northern Switzerland, a significant amount of incision can be explained by drainage reorganization. Key Points Drainage capture has caused significant erosion along the Rhine River The transient erosional wave propagates quickly through the landscape The incision is a significant fraction of Plio‐Pleistocene erosion in the regionPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99064/1/jgrf20056.pd

Continuous Monitoring of Software Services: Design and Application of the Kieker Framework

In addition to studying the construction and evolution of software services, the software engineering discipline needs to address the operation of continuously running software services. A requirement for its robust operation are means for effective monitoring of software runtime behavior. In contrast to profiling for construction activities, monitoring of operational services should only impose a small performance overhead. Furthermore, instrumentation should be non-intrusive to the business logic, as far as possible. We present the Kieker framework for monitoring software runtime behavior, e.g., internal performance or (distributed) trace data. The flexible architecture allows to replace or add framework components, including monitoring probes, analysis components, and monitoring record types shared by logging and analysis. As a non-intrusive instrumentation technique, Kieker currently employs, but is not restricted to, aspect-oriented programming. An extensive lab study evaluates and quantifies the low overhead caused by the framework components. Qualitative evaluations provided by industrial case studies demonstrate the practicality of the approach with a telecommunication customer self service and a digital photo submission service. Kieker is available as open-source software, where both the academic and industrial partners contribute to the code. Our experiment data is publicly available, allowing interested researchers to repeat and extend our lab experiments