Bargaining in the Photonics Industry

This paper investigates how path dependence may come about in inter- organizational networks. To do so, we focus our analysis on one particular type of network management practices – bargaining practices – and ask whether and how they can become path-dependent. Bargaining practices are recurrent activities through which network partners agree to identify and distribute their cooperative surplus. Targeting these practices, we first operationalize the core concepts of path dependence theory by deriving empirical indicators. We then use a ‘pattern matching’ approach to analyze whether these empirical indicators can be found in real bargaining practices. Empirically, we conduct three case studies of regional networks in the photonics industry. We use qualitative interviews and content analysis to reconstruct the development dynamics of their bargaining practices. A major finding is that network bargaining practices can indeed exhibit inter-organizational path dependencies. This paper contributes not only by operationalizing the theory of organizational path dependence but also by extending this theory to the network level of analysis

Ecological comparison of spiders (Arachnida: Araneae) from short rotation coppice plots and from arable fields

Kurzumtriebsflächen, oder auch Energiewälder bzw. Schnellwuchsplantagen genannt, sind Flächen mit schnellwachsenden Baumarten (z. B. Hybridpappeln), die in kurzen Umtriebszeiten von 2 bis 10 Jahren bewirtschaftet werden. Nach der zyklischen Ernte treiben die Bäume wieder aus (Stockausschlag) und können nach einigen Jahren erneut genutzt werden. Das Prinzip der schnellwüchsigen Baumarten ist dem früher weit verbreiteten Niederwald ähnlich, allerdings mit dem Unterschied, dass der Energiewald in der Regel auf stillgelegten landwirtschaftlichen Flächen angebaut wird und bei der Begründung züchterisch bearbeitetes Material von Pappel, Aspe und Weide verwendet wird. Kurzumtriebsflächen dienen vorwiegend der Holzproduktion (v. a. Hackschnitzel) zur Gewinnung von (Wärme-)Energie. Spinnen (Arachnida: Araneae) kommen in allen terrestrischen Lebensräumen in großer Artenzahl vor. Allein auf dem Gebiet Deutschlands sind derzeit über 1000 verschiedene Spinnenarten bekannt (Blick & al. 2004). Spinnen ernähren sich räuberisch, wobei ihre Beutetiere meist andere Arthropoden darstellen. Aufgrund der spezifischen Ansprüche vieler Arten an bestimmte (Mikro-)Habitate und damit an spezielle Lebensraumanforderungen eignen sie sich besonders für die qualitative Charakterisierung von Groß- und Kleinlebensräumen. Auch die Veränderung von Lebensräumen durch verschiedene Einflüsse (z. B. Änderung der Nutzungsintensität, Schadstoffimmissionen, Entwässerung, Sukzession, etc.) kann durch Spinnen gut bewertet und dokumentiert werden. Sie werden deshalb häufig bei der Beurteilung der Schutzwürdigkeit von Flächen, bei Eingriffsgutachten, Erfolgskontrollen, Umweltverträglichkeitsuntersuchungen sowie zum Biotopmonitoring herangezogen und zunehmend als Indikatorgruppe für die Bewertung von Habitaten verwendet (z. B. Clausen 1986, Gack & al. 1999). Bisher gibt es nur wenige publizierte Studien zum Vorkommen und zu den Entwicklungstendenzen der epigäischen Arthropodenfauna auf Energiewaldflächen (Blick & Burger 2002, Blick & al. 2003). Mit der vorliegende Untersuchung sollen daher exemplarisch die Auswirkungen solcher Kurzumtriebs-Versuchsflächen auf die epigäische Raubarthropodenfauna beleuchtet werden. Als eine der wichtigsten Prädatorengruppen wurde die Ordnung der Spinnen (Araneae) gewählt, die aufgrund der hohen Arten- und Individuenzahl sowie oft spezifischer Biotopansprüche der einzelnen Arten besonders geeignet erscheint. Besonderes Interesse erweckt bei vorliegender Untersuchung die Fragestellung, ob sich innerhalb weniger Jahre waldtypische Spinnenarten einstellen und inwieweit sich die Spinnenfauna bezüglich des Ausgangsstadiums „Acker“ verändert (Sukzession). Darüber hinaus wurde ermittelt, welche Auswirkungen die Ernte eines aufstockenden Energiewaldes auf die Spinnenzönose haben kann.An experimental plot with fast growing tree species (poplar) was founded in 1992 near Neustadt an der Waldnaab (Bavaria, Germany). In the first, second and third five year rotation period the spiders (Arachnida: Araneae) were investigated. For comparison adjacent habitats (arable farm land, forest) were included in the study. In the 4th, 9th and 15th year after plantation the community of spiders differed clearly from arable farm land and even more from forest fauna. Similarity indices show a distinct directed succession. The results have been compared with other succession lines of other investigations and are regarded as typical. In conclusion, the study discusses spiders in short rotation coppice plots, both generally and in terms of nature conservation aspects

Karadeniz korsanlar kralı İpsiz Recep’in Kuvayımilliye'deki hayretbahş maceraları

Haftalık Mecmua'da tefrika edilen Karadeniz Korsanlar Kralı İpsiz Recep’in Kuvayımilliye'deki Hayretbahş Maceraları adlı romanTefrikada yazarın adı belirtilmemiştir

Radio-Frequency-Controlled Urea Dosing for NH3-SCR Catalysts : NH3 Storage Influence to Catalyst Performance under Transient Conditions

Current developments in exhaust gas aftertreatment led to a huge mistrust in diesel driven passenger cars due to their NOx emissions being too high. The selective catalytic reduction (SCR) with ammonia (NH3) as reducing agent is the only approach today with the capability to meet upcoming emission limits. Therefore, the radio-frequency-based (RF) catalyst state determination to monitor the NH3 loading on SCR catalysts has a huge potential in emission reduction. Recent work on this topic proved the basic capability of this technique under realistic conditions on an engine test bench. In these studies, an RF system calibration for the serial type SCR catalyst Cu-SSZ-13 was developed and different approaches for a temperature dependent NH3 storage were determined. This paper continues this work and uses a fully calibrated RF-SCR system under transient conditions to compare different directly measured and controlled NH3 storage levels, and NH3 target curves. It could be clearly demonstrated that the right NH3 target curve, together with a direct control on the desired level by the RF system, is able to operate the SCR system with the maximum possible NOx conversion efficiency and without NH3 slip

Radio-Frequency-Based NH₃-Selective Catalytic Reduction Catalyst Control : Studies on Temperature Dependency and Humidity Influences

The upcoming more stringent automotive emission legislations and current developments have promoted new technologies for more precise and reliable catalyst control. For this purpose, radio-frequency-based (RF) catalyst state determination offers the only approach for directly measuring the NH3 loading on selective catalytic reduction (SCR) catalysts and the state of other catalysts and filter systems. Recently, the ability of this technique to directly control the urea dosing on a current NH3 storing zeolite catalyst has been demonstrated on an engine dynamometer for the first time and this paper continues that work. Therefore, a well-known serial-type and zeolite-based SCR catalyst (Cu-SSZ-13) was investigated under deliberately chosen high space velocities. At first, the full functionality of the RF system with Cu-SSZ-13 as sample was tested successfully. By direct RF-based NH3 storage control, the influence of the storage degree on the catalyst performance, i.e., on NOx conversion and NH3 slip, was investigated in a temperature range between 250 and 400 °C. For each operation point, an ideal and a critical NH3 storage degree was found and analyzed in the whole temperature range. Based on the data of all experimental runs, temperature dependent calibration functions were developed as a basis for upcoming tests under transient conditions. Additionally, the influence of exhaust humidity was observed with special focus on cold start water and its effects to the RF signals

Epoxidation of Olefins Catalyzed by Sulfate-based Supramolecular Ion Pairs

The development of inexpensive and effective catalysts for the epoxidation of olefins to epoxides, which are key commodities for the chemical industry, is a continuing challenge. In this context, we present a supramolecular solution with the development of new host-guest assemblies of sulfate ions and amidoammonium receptor cations that, for the first time, are shown to act as catalysts for olefin epoxidation by hydrogen peroxide under biphasic conditions. Analysis of the reaction mechanism shows that the reactive and oxidizing peroxymonosulfate is formed in the organic phase. Furthermore, a variety of readily available precursors may be used to form the supramolecular ion pairs (SIPs), which is enabling a large-scale synthesis of the catalysts while maintaining catalytic control and effectiveness.</p

The Residual Method for Regularizing Ill-Posed Problems

Although the \emph{residual method}, or \emph{constrained regularization}, is frequently used in applications, a detailed study of its properties is still missing. This sharply contrasts the progress of the theory of Tikhonov regularization, where a series of new results for regularization in Banach spaces has been published in the recent years. The present paper intends to bridge the gap between the existing theories as far as possible. We develop a stability and convergence theory for the residual method in general topological spaces. In addition, we prove convergence rates in terms of (generalized) Bregman distances, which can also be applied to non-convex regularization functionals. We provide three examples that show the applicability of our theory. The first example is the regularized solution of linear operator equations on $L^p$-spaces, where we show that the results of Tikhonov regularization generalize unchanged to the residual method. As a second example, we consider the problem of density estimation from a finite number of sampling points, using the Wasserstein distance as a fidelity term and an entropy measure as regularization term. It is shown that the densities obtained in this way depend continuously on the location of the sampled points and that the underlying density can be recovered as the number of sampling points tends to infinity. Finally, we apply our theory to compressed sensing. Here, we show the well-posedness of the method and derive convergence rates both for convex and non-convex regularization under rather weak conditions.Comment: 29 pages, one figur

Development and in-vitro characterization of an implantable flow sensing transducer for hydrocephalus

An implantable transducer for monitoring the flow of Cerebrospinal fluid (CSF) for the treatment of hydrocephalus has been developed which is based on measuring the heat dissipation of a local thermal source. The transducer uses passive telemetry at 13.56MHz for power supply and read out of the measured flow rate. The in vitro performance of the transducer has been characterized using artificial Cerebrospinal Fluid (CSF) with increased protein concentration and artificial CSF with 10% fresh blood. After fresh blood was added to the artificial CSF a reduction of flow rate has been observed in case that the sensitive surface of the flow sensor is close to the sedimented erythrocytes. An increase of flow rate has been observed in case that the sensitive surface is in contact with the remaining plasma/artificial CSF mix above the sediment which can be explained by an asymmetric flow profile caused by the sedimentation of erythrocythes having increased viscosity compared to artificial CSF. After removal of blood from artificial CSF, no drift could be observed in the transducer measurement which could be associated to a deposition of proteins at the sensitive surface walls of the packaged flow transducer. The flow sensor specification requirement of +−10% for a flow range between 2ml/h and 40ml/h. could be confirmed at test conditions of 37°

Nanofiber-based aerogels

Nanofiber-based aerogels or sponges are made from preformed polymeric nanofibers. They are very porous, ultralight and have a large internal surface as classical aerogels. But their network of interconnected fibers renders them also elastic and mechanically resilient. Moreover, they show a hierarchic architecture with minor primary pores between tangled nanofibers and major cell-like pores. Nanofiber aerogels can be tailored to many applications due to flexibility in the choice of polymer together with the possibility to chemically modify the surface of the fibers. Possible applications include filtration, thermal insulation, support for catalysts, or scaffolds for tissue engineering. Mostly, synthetic polymers such as PAN and PVA have been used as fiber materials or their blends with biopolymers such as pullulan and gelatin

Few-cycle laser driven reaction nanoscopy on aerosolized silica nanoparticles

Nanoparticles offer unique properties as photocatalysts with large surface areas. Under irradiation with light, the associated near-fields can induce, enhance, and control molecular adsorbate reactions on the nanoscale. So far, however, there is no simple method available to spatially resolve the near-field induced reaction yield on the surface of nanoparticles. Here we close this gap by introducing reaction nanoscopy based on three-dimensional momentum-resolved photoionization. The technique is demonstrated for the spatially selective proton generation in few-cycle laser-induced dissociative ionization of ethanol and water on SiO2 nanoparticles, resolving a pronounced variation across the particle surface. The results are modeled and reproduced qualitatively by electrostatic and quasi-classical mean-field Mie Monte-Carlo (M3C) calculations. Reaction nanoscopy is suited for a wide range of isolated nanosystems and can provide spatially resolved ultrafast reaction dynamics on nanoparticles, clusters, and droplets