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A key claim in bureaucratic reputation literature is that reputation has several dimensions. This presents agencies with a difficult choice concerning which dimension(s) they should emphasize in the management of their reputation. This paper analyzes how regulatory agencies manage their reputation through communicative responses to public judgments, based on a single-case study of the German financial regulator BaFin. Our theoretical argument underscores the importance of different reputational dimensions for regulatory agencies that simultaneously considers their distinct reputation reserves. Our main finding was that BaFin prioritizes responses to public judgments targeting reputational dimensions that are central to its mission and for which the agency has a weak reputation, as opposed to judgments targeting dimensions that are central to its mission and for which it has a strong reputation, or judgments targeting peripheral dimensions. The paper demonstrates the importance of agency missions for reputation management and suggests directions for further research.

The terahertz range of the electromagnetic spectrum reveals important insights when studying material properties. An ultra-broadband terahertz time-domain spectroscopy system based on state-of-the-art, high-stability organic nonlinear optical crystals used as both THz wave generator and detector is presented. In transmission geometry, a broad spectrum exceeding 20 THz and a high dynamic range of more than 80 dB is achieved using a compact 100 MHz femtosecond laser working at telecom wavelength 1560 nm. In the normal-incidence reflection geometry, a similar bandwidth with a dynamic range surpassing 60 dB is reported. The experimental results are supported by a complete theoretical model, which includes the pump pulse duration, THz phonon/vibrational modes of the organic crystals and optical/THz beam path optimizations. The effectiveness of the newly developed system is demonstrated by measuring pharmaceutical samples with distinct THz features in the ultra-broadband THz range and by measuring narrow water vapor lines at a spectral resolution of 2.7 GHz (0.090 cm−1), resulting in an excellent accuracy with a frequency deviation of less than 0.05% from the reference values.

For electrically powered applications such as consumer electronics and especially for electric vehicles a precise state-of-charge estimation for their lithium-ion batteries is desired to reduce aging, e.g. avoiding detrimental states-of-charge. Today, this estimation is performed by battery management systems that solely rely on charge bookkeeping and cell voltage measurements. In the present work we introduce a new, physical probe for the state-of-charge based on ultrasonic transmission. Within the simple experimental setup raised cosine pulses are applied to lithium-ion battery pouch cells, whose signals are sensitive to changes in porosity of the graphite anode during charging/dis-charging and, therefore, to the state-of-charge. The underlying physical principle can be related to Biot's theory about propagation of waves in fluid saturated porous media and by including scattering by boundary layers inside the cell.

DSTMS organic electro-optic crystal is a very promising and efficient THz-wave generation material. It allows for both very high THz electric fields generation, exceeding several GV/m using optical rectification of femtosecond laser pulses, as well as the possibility for extremely broad bandwidth extending well beyond 10 THz [1]. However, the usual laboratory THz systems based on these crystals exploit very bulky and expensive fs laser systems [2], which are not desired for industrial THz imaging and spectroscopy applications [3,4]. Recently, some compact system employing organic crystals were demonstrated [5], however they use a conventional photoconductive antenna as a THz-wave detector. Here we present a compact THz time-domain spectroscopy system based on a relatively low-cost and small-size femtosecond fiber lasers operating at 1560 nm. As the THz generation and detection material, we choose the organic crystal DSTMS (4-N,N-dimethylamino-4‘-N‘-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate), since it reaches the highest overall efficiency and the flattest spectrum among the presently known state-of-the-art organic crystals (Figure 1).

We demonstrate ultrabroadband THz-wave generation and detection in a compact system based on a femtosecond fiber laser at 1560 nm and optical rectification in organic electro-optic crystals DSTMS. Terahertz time-domain spectroscopy with a spectrum extending up to 20 THz with a maximum bandwidth exceeding 70 dB is possible with this system.

Bach and Wegrich introduce the key theme of the volume, which revolves around understanding how routine processes of decision-making in public sector organizations potentially lead to problematic outcomes in terms of coordination and problem solving. Instead of viewing those outcomes as the result of organizational or individual pathologies, the chapter traces the origins of non-coordination within and between organizations to intentionally rational organizational behaviour. Conceptualizing blind spots as part of a larger universe of biases in organizational attention, based on established theoretical notions of bounded rationality and institutionalized organizations, the authors show how different types of attention biases provide novel insights into seemingly irrational or uncoordinated administrative behaviour.

This concluding chapter addresses two ‘so what?’ questions raised throughout the volume. First, if attention biases are a pertinent factor in organizational life in political contexts, what can be done about them? Bach and Wegrich discuss three public sector reform approaches (joined-up government, impact assessment, and behavioural insights) in terms of how, and how successfully, they address different attention biases. Second, how can research on organizational attention biases take the role of institutional context systematically into account and explore particular different institutions’ vulnerabilities to organizational attention biases? Two ideal-type institutional modes of coordination—hierarchical and negotiated coordination—are discussed in terms of their susceptibility to attention biases. Taken together, the discussion of these two questions outlines an agenda for future research the volume seeks to stimulate.

Second-life applications of automotive lithium-ion batteries are currently investigated for grid stabilization. Reutilization depends on reliable projections of the remaining useful life. However, reports on sudden degradation of lithium-ion-cells near 80% state of health challenge these extrapolations. Sudden degradation was demonstrated for different positive active materials. This work elucidates the cause of sudden degradation in detail. As part of a larger study on nonlinear degradation, in-depth analyses of cells with different residual capacities are performed. Sudden degradation of capacity is found to be triggered by the appearance of lithium plating confined to small characteristic areas, generated by heterogeneous compression. The resulting lithium loss rapidly alters the balancing of the electrodes, thus generating a self-amplifying circle of active material and lithium loss. Changes in impedance and open-circuit voltage are explained by the expansion of degraded patches. Destructive analysis reveals that sudden degradation is caused by the graphite electrode while the positive electrode is found unchanged except for delithiation caused by side reactions on the negative electrode. Our findings illustrate the importance of homogeneous compression of the electrode assembly and carbon electrode formulation. Finally, a quick test to evaluate the vulnerability of cell designs toward sudden degradation is proposed.

The potential reuse of lithium-ion batteries exhausted upon electric vehicle operation is a broadly discussed topic. However, a profound understanding of battery aging behavior is a prerequisite to assess overall system cost and economic benefit of battery reuse: Whereas the capacity fade under load is commonly reported to show a linear dependency on charge throughput, a turning point to nonlinear aging characteristics is observed at residual capacities of about 80% under different operational conditions. Based on a widespread aging matrix, results indicate an earlier appearance of nonlinear characteristics at high charging rates and operational voltage windows but low temperatures. Scanning electron microscopy images reveal areas of thick surface films at the anode while the cathode stays unmodified. Therefore, a thickening of the solid electrolyte interphase, catalyzed by oxidation products migrating to the anode, is believed to be the dominating aging mechanism before the turning point. Afterwards, lithium plating might even occur at moderate temperatures and charging rates due to deteriorated ionic kinetics and graphite active material loss. As all these mechanisms are dependent on the cell potential, an optimized operational strategy may avoid or retard nonlinear aging characteristics and extend the life of lithium-ion cells.

Within this paper, the structural optimization of stiffened composite panels is considered. The application example is a wing of a long–range aircraft, whereby the flexibility has to be increased due to flight physical demands. To develop the new structural design concept, numerical optimization is used. The structural analysis is carried out utilizing detailed finite element models (DFEM) with linear static and linear eigenvalue simulations. Using this DFEM– and gradient–based optimization environment, designs are analyzed and optimized regarding their mass, considering damage tolerance and stability requirements.

The politicization of bureaucracy is a widespread strategy to increase the political control of ministerial departments in parliamentary democracies. It is, however, largely unknown why executive politicians promote some officials rather than others to high public office. Based on a unique dataset of all senior officials in German federal ministries and agencies that held office in the period 1997–2015, this article investigates whether partisan loyalty, political craft, and managerial competencies influence the chance of promotion to the highest civil service position in Germany (state secretary). We apply event history modeling to draw inferences on the relative importance of different selection criteria used by ministers when recruiting state secretaries from a candidate pool of senior officials. A key finding is that ministers consistently prefer politically loyal to nonloyal candidates. Although ministers also consider candidates’ political craft and selected managerial competencies, they are likely to trade-off partisan loyalty against those qualifications. The article contributes to the literature on politicization in the public sector by comparing potential and actual office holders and by including a broad set of selection criteria, moving beyond the literature’s dominating focus on partisan loyalty. The methodological approach developed in this article may well be transferred to other institutional contexts and used for comparative studies in this area.

Components in the power grid require security, high availability and real-time communications for reliable operation. But these components are based on software that contains issues that need to be fixed. Timely installation of software updates allows securing vulnerable software quickly but conventionally disrupts availability and communications. Rolling updates on redundant systems prevent such disruptions but delay update installations as they need to be prepared carefully to update reliably. Dynamic Software Updating shortens the installation duration of updates by implementing them in-memory, allowing timely hot-fixing and installation of new features without service disruption or degradation in soft real-time communications. As the Smart Grid settles on standardization and common technologies for interoperability, the need for timely hot-fixing and updating of software applications and libraries which are in widespread use increases.

Applications in the Internet of Things require security, high availability and real-time communications for reliable operation. But their software contains issues that need to be fixed. Timely installation of software updates allows securing vulnerable software quickly but conventionally disrupts availability and communications. Rolling update schemes prevent disruptions, but have to be performed carefully.Dynamic software updating significantly shortens the installation duration of updates by implementing them in-memory, allowing timely hot fixing and installation of new features without service disruption or degradation in soft real-time communications. As the Web of Things settles on common technologies, we see the need for quick hot fixing of security vulnerabilities in widespread components.To demonstrate the benefits, we present a case study in which the moquette message broker has been retrofitted for dynamic updating with our update system. We provide dynamic patches for all three releases of moquette and perform these updates on moquette at saturated load stressed by a 1:10 fan-out benchmark with 100 simulated publishers. While no connections or messages are lost, it demonstrates that the throughput drops only for 1-2s and that average message latency peaks up to 1000ms during this time.

Purpose The purpose of this paper is to present a structural design and optimization module for aircraft structures that can be used stand-alone or in a high-fidelity multidisciplinary design optimization (MDO) process. The module is capable of dealing with different design concepts and novel materials properly. The functionality of the module is also demonstrated. Design/methodology/approach For fast sizing and optimization, linear static finite element (FE) models are used to obtain inner loads of the structural components. The inner loads and the geometry are passed to a software, where a comprehensive set of analytical failure criteria is applied for the design of the structure. In addition to conventional design processes, the objects of stiffened panels like skin and stringer are not optimized separately and discrete layups can be considered for composites. The module is connected to a design environment, where an automated steering of the overall process and the generation of the FE models is implemented. Findings The exemplary application on a transport aircraft wing shows the functionality of the developed module. Originality/value The weight benefit of not optimizing skin and stringer separately was shown. Furthermore, with the applied approach, a fast investigation of different aircraft configurations is possible without constraining too many design variables as it often occurs in other optimization processes. The flexibility of the module allows numerous investigations on influence of design concepts and failure criteria on the mass and layout of aircraft wings.

In battery applications, every electrical connection of battery cells is important because it influences functionality, efficiency, and safety. Increased contact resistances generate more heat at the affected terminals and if contact resistances of parallel-connected battery cells differ the current divides unequally. Amongst different techniques, detachable connections are easy to handle and have advantages for service, repair and recycling. Usually, detachable electrical connections are based on the functional principle of press contacts. So, press contacts are frequently used for consumer batteries in electronic devices, for pouch battery cells in scientific tests, and for large battery cells with screw connections. This paper focusses on the electrical contact resistance of press contacts for battery cells. A novel measuring method to assess the contact resistance itself is presented. Common terminal and connector metals for battery cells and the dependence of their contact resistances on the contact pressure, surface roughness, and contact area are investigated and compared with welding techniques. Only if these dependencies are considered, contact resistances as low as for welded connections are achieved. Furthermore, due to its hard passivating Al 2 0 3 surface film, aluminum contacts need a certain surface roughness. The obtained results can serve for modeling and development of battery assemblies.

Lithium-ion batteries are increasingly used in mobile applications where mechanical vibrations and shocks are a constant companion. This work shows how these mechanical loads affect lithium-ion cells. Therefore pouch and cylindrical cells are stressed with vibrational and shock profiles according to the UN 38.3 standard. Additionally, a vibration test is set up to reflect stress in real-world applications and is carried out for 186 days. The effects of the load profiles on the tested cells are investigated by capacity measurement, impedance spectroscopy, micro-X-ray computed tomography and post mortem analyses. The mechanical stress has no effect on the investigated pouch cells. Although all tested cylindrical cells would pass the standard tests, in certain cells stressed in a vertical position the mandrel dispatched itself and struck against internal components. This caused bruised active materials, short circuits, a damaged current collector and current interrupt device. The investigations are not directly transferrable to all pouch or cylindrical cells but show that the mechanical cell design, especially the fixation of the internal components, determines whether a cell withstands vibrations and shocks. Depending on the cell design and the loading direction, long-term vibrational loads can have additional detrimental effects on lithium-ion cells compared to standard tests.

This paper presents a structure design and optimization module, developed for the application inside multi-disciplinary optimization process chains. The loads necessary for sizing and optimization are calculated in CFD or aeroelastic calculations and applied on a Finite Element Model that represents all primary structural elements of a wing. The FE model is created automatically from a parametric geometry description. The deformations and inner loads of the wingbox are calculated via linear static FE calculations; geometry and loads are provided to an external sizing tool. Each component has a set of design variables with discrete design points which are permutated to get the component’s design candidates. A set of failure criteria is used to size the structure which can be made of composites or metal. The methodology is applied to the optimization of a forward swept composite for a short range aircraft and a design study comparing different stringer types and their influence on mass and structural deformation of the wing is performed.

We demonstrate efficient generation of narrowband (

The creation of executive agencies outside core departments has been a major element of administrative reforms throughout Europe during the past two decades, driven by a managerial logic, which also has been at the core of most academic works on "agencification." In this article, the authors take a different perspective by focusing on executive agencies' influence in the policy process. The authors analyze the policy influence of a large executive agency with service delivery tasks in the context of a parliamentary system of government (Flanders, Belgium). A comparison of the agency's influence in two major policy processes shows that a complex interplay of policy content, patterns of interaction, and mutual trust with the political leadership and organizational characteristics helps in explaining the observed patterns of influence. The findings also raise normative concerns regarding potential problems of disconnecting operations from policy formulation via agencification. © 2012 SAGE Publications.

A tunable THz source for remote sensing has been realized using difference frequency generation of the signal and idler wavelengths of a BBO based optical parametric oscillator [1]. THz pulses with frequencies 1 – 20 THz and a bandwidth of less than 100 GHz are produced in two operational modes via difference frequency generation (DFG) process by mixing two infrared waves in novel organic crystals with extremely high optical nonlinearities (DSTMS and OH1) [2]. One operational mode is at a fixed THz wavelength of 1.25 THz for high output powers using OH1 as organic material for stand-off applications, and the second mode is for tuning between 1 – 20 THz using the organic crystal DSTMS for spectroscopy applications. The optimum wavelength range in view of the material properties of DSTMS and OH1 is centered at 1400 nm.

We report, for the first time to our knowledge, on picosecondpulse optical phase conjugation using photorefractive Sn(2)P(2)S(6) crystals. For 7.2-ps pulses at 1.06 mum, we have achieved phase-conjugate reflectivities of up to 45% with very fast build-up times, about 15 ms at an intensity of 23 W/cm(2) using Te-doped Sn(2)P(2)S(6). We furthermore demonstrate aberration-free 5 W optical output of 8-ps pulses at 1.06 mum from a side pumped Nd:YVO(4) amplifier using the Sn(2)P(2)S(6)-based phase-conjugate feedback.

Although Germany does not figure among the ‘forerunners’ of managerial reforms of the public sector, it has a long tradition of agencies and non-departmental bodies at the federal level. Over time, the federal administration has developed into a highly differentiated ‘administrative zoo’ with a large number of species, questioning the image of a well-ordered German bureaucracy. The article addresses organizational changes among non-ministerial agencies during the past 20 years and ministry—agency relations, drawing on data from a comprehensive survey of the federal administration. The structural changes we observe are neither comprehensive nor planned; they are much more evolutionary than revolutionary, driven by sectoral policies and not by any overall agency policy, supported more by regulatory than by managerial reforms, and most of the changes are horizontal mergers or successions of existing organizations, while we find almost no evidence for hiving-off from ministries to agencies. At the same time, federal agencies report a lot of bureaucratic discretion, whereas they perceive substantial levels of ‘red tape’ due to administrative regulations. We also find that traditional, hierarchical modes of ministerial oversight are still dominating; only few agencies have performance agreements with measurable goals. Points for practitioners The article will be of interest to practitioners concerned about the nature and direction of organizational change within government, especially about processes of horizontal and vertical differentiation and steering. It demonstrates that even in a highly developed and classical bureaucratic administrative system such as Germany there is and has for a long time been a large variety of governmental agencies that enjoy a considerable amount of autonomy. At the same time there is continuous change and adaptation to new circumstances, even though all this has very little to do with international modernization trends such as New Public Management or comprehensive agencification.

High-power solid-state lasers with high beam quality are needed for many scientific and industrial applications. Thermal aberration effects in laser or amplifying material occurring at high optical intensities present one of the most critical limiting factors to achieve high-efficiency single-spatial-mode operation. To compensate for wavefront distortions and thermal lensing effects, optical phase conjugate mirrors (PCMs) based on photorefractive materials present an attractive solution, as demonstrated for several lasers and amplifiers from cw to ps regime using BaTiO 3 :Rh crystals [1–3]. The main problem of such systems is the very long temporal response of BaTiO 3 :Rh (seconds/minutes) as well as its tendency of domain formation.

The paper reports on the enhancement of the photorefractive characteristics by doping Sn2P2S6 with tellurium (Te) and antimony (Sb). A two-wave mixing measurement is performed in the wavelength range from 633 nm to 1064 nm and compare the doped crystals to conventional pure Sn2P2S6. By Sb doping the two-wave mixing gain Gamma at 633 nm is relatively high ( Γ= 20 cm-1), but is surpressed for wavelengths larger than 780 nm. A self-pumped optical phase conjugation in a ring cavity is also studied.

International audience; The photorefractive properties of Sn2P2S6 crystals doped with Te and Sb in the near-infrared wavelength range up to 1064 nm are reported. The main photorefractive parameters, i.e., two-wave mixing gain, effective electro-optic coefficient, diffusion length, concentration of traps, and response time, are compared with conventional nominally pure Sn2P2S6. Te-doped Sn2P2S6 shows the fastest response with the smallest decrease of the photorefractive efficiency with increasing wavelength in the near infrared. Sb doping, on the other hand, inhibits photorefraction in the near infrared. Sn2P2S6:Te and Sn2P2S6:Sb crystals both show a high two-wave mixing gain Γ at 633 nm, and 10 and 20 cm−1. Te-doped Sn2P2S6 shows a photorefractive gain of 4.5 cm−1 at 1064 nm. Response times at 1064 nm of 20 ms have been measured for the intensity 6 W⁄cm2, which is 2 orders of magnitude shorter than in Rh-doped BaTiO3.

We demonstrate self-pumped optical phase conjugation in Te-doped Sn 2 P 2 S 6 up to a wavelength of 1.06 μm. A phase conjugate reflectivity of more than 40 percent with a very fast rise time below 100 ms has been measured.

In this work the effects of sub-resolution assist features (SRAF) on the process window and the target CD control are investigated for the 100nm node gate level. Using 2-dimensional lithographic simulations the process windows of critical isolated and dense structures are determined and the overlapping process window with a second, dense feature is computed. This is achieved using a novel scheme of simulations over a wide range of line widths for a large pitch range. This approach allows us to explore systematically and simultaneously the impact of line width bias, number of placed assists, spacing to the main feature and spacing between the assist features as well as the assist feature width over a large parameter space. The overlapping process window is optimized following two different strategies: The first strategy places the assists only considering the space between two features independent of their width while reaching the target values for the different feature width using line biases. The second strategy under investigation defines the assist feature parameters based on both the line width of the target feature as well as the space from the target feature to the neighboring feature. For both approaches the implication for target CD control is discussed.

We demonstrate double phase-conjugation in pure and Te-doped Sn(2)P(2)S(6), a semiconducting ferroelectric material, at the wavelength of 685 nm. We observe a phase conjugate reflectivity of more than 800% at an intensity ratio of the pump beams of 44 for Te-doped Sn(2)P(2)S(6). Using a laser diode bar emitting at 685 nm, we demonstrate double phase conjugation of three independent emitters of the laser diode bar with a single mode master laser. By adjusting the center wavelength of the master laser to the center wavelength of an emitter with an accuracy of less than 0.1 nm, locking of any emitter of the laser diode bar is demonstrated. We improve the spectral width of the emitter from 0.5 nm to below 2.5 x 10(-4) nm.

We show that by doping Sn2P2S6 crystals, the near-infrared photorefractive sensitivity can be enhanced or suppressed. In Te-Sn2P2S6, fast self-pumped optical phase conjugation with a rise time below 100 ms at 1.06 µm has been demonstrated.