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The paper discusses methods to increase the level of automation in ship handling towards autonomous operations with a focus on conventional vessels in maneuvering situations. In this context, a model-based approach for control system design of maneuvering vessels is introduced. The resulting model is applied to a multivariable control system including allocation, feedforward, and feedback modules. The established hybrid control system distinguishes between a transit mode with control in two degrees of freedom in compliance with the prevailing traffic regulations and a dynamic positioning mode in three degrees of freedom for the final stages of a berthing maneuver. The supervisor switches automatically between these two modes. The methods are validated on board the German research vessel DENEB in the port of Rostock.

Video abstract:https://youtu.be/e51xfphj4R0 The paper presents a method for gradual automation of ship manoeuvring, focusing on ships already in service. The approach involves the expert knowledge of both nautical officers and ship engineers to optimise the operational behaviour and reduce fuel consumption and emissions. Detailed models of dynamic ship motion and engine processes form the basis of various software tools to assist the manual planning and execution of effective voyages. The results of a study in ship handling simulator show that the manual manoeuvring efficiency of experienced nautical officers has also been significantly increased by these assistance instruments. With regard to automatic shipping, the generated optimal plan is transferred to the automatic control system as a target trajectory. Based on a simplified motion model, the controller structure with feed-forward and feedback modules was developed to realise velocity, heading and track control. Results of controller application in simulator tests with and without wind disturbances are presented. In addition, the paper describes the development of necessary framework conditions for safety-critical areas for the application of automatically controlled manoeuvres in today’s practice with the so-called nautical algorithms according to the research project GALILEOnautic 2.

This paper presents the development of a networked control system for maritime applications within the joint project GALILEOnautic to enable autonomous shipping and optimal maneuvering in harbor environments. To achieve this objective, all networked vehicles estimate position, velocity, orientation and time dynamically using a maritime navigation filter. These vehicle states are broadcasted to a central computation unit via long term evolution (LTE) mobile communication in combination with virtual private network (VPN). After a data synchronization step, an optimization algorithm uses the vessel states to calculate model-based optimal trajectories for each networked participant. These trajectories consist of target positions at certain instants of time and optimal settings for the rudder and propulsion units which are used as feedforward variables for a local trajectory controller on each vessel. To compensate smaller errors due to model inaccuracies during trajectory calculation, a feedback control loop is also established. Beside active network participants, other vehicles can be considered as well using data which is broadcasted by the automatic identification system (AIS). This paper presents the promising results of GALILEOnautic demonstrating an encounter situation of two networked vessels and one disturbing, non-networked participant. To demonstrate how the approach is able to avoid critical situations, three different demonstrators with increasing complexity are shown: networked robots, unmanned surface vehicles, and a ship-handling simulator.

The German joint project GALILEOnautic aims to develop systems for autonomous navigation and optimised manoeuvring of vessels cooperating in areas with high safety and efficiency requirements, such as harbours or narrow waterways. In the conception of this project, the SAE levels of the automotive industry were applied for classification of intended levels in automation of already being used manoeuvring vessels. It fairly soon became apparent that the conditions in development of new autonomous road vehicles and the appropriate infrastructure are significantly different in comparison to adaption of navigation and manoeuvring of watercrafts which are part of a complex transport network. Therefor and in relation to the few orientating guidelines addressing autonomous maritime applications, a specific concept for manoeuvring automation in high safety areas was developed. It defines the automation levels towards autonomous shipping considering the current practice and the technical equipment on such vessels, the legal framework for automatic shipping as well as the requirements for integrating automatic manoeuvring in the traditional shipping traffic. The contribution introduces this automation concept and the necessary infrastructure for each level. Additionally, the results of the first project phase are presented. It implies the essential sensor equipment and subsequent data fusion to describe completely the dynamic ship motion and to recognise the close surrounding of the vessel. A hybrid control scheme is applied including feedforward and feedback modules. The control approach is illustrated by interfered encounter situations in ship handling simulator and for unmanned surface vehicles. The paper gives a prospect on the future investigations for higher manoeuvre automation.

International Maritime and Port Technology and Development Conference, MTEC 2019, Trondheim, Norway, 13 Nov 2019 - 14 Nov 2019; Bristol : IOP Publ. (2019). doi:10.1088/1742-6596/1357/1/012019, Published by IOP Publ., Bristol

The paper presents a review of major features of the crystalline silicon on glass (CSG) technology, its achievements, limitations and challenges, and latest developments. CSG cells are fabricated by solid-state crystallisation (SPC) of 1.5–3.5 µm thick precursor diodes prepared by PECVD or ebeam evaporation followed by thermal annealing, hydrogen passivation and metallisation. The highest efficiency of 10.4% was demonstrated on a PECVD minimodule on textured borosilicate glass. The best performing ebeam-evaporated cells on planar glass reached 8.6% efficiency. CSG cells were also produced on low-cost soda-lime glass with 8.1% and 7.1% efficiencies on PECVD and ebeam material respectively. The performance of SPC CSG cells is limited to below 11% because high defect density in SPC material limits V OC and 1.5–3.5 µm cell thickness limits J SC . A breakthrough came about when thicker poly-Si films with low defect density on glass were prepared by liquid-phase crystallisation (Amkreutz, 2011) leading to development of the next generation, liquid-phase crystallised silicon on glass (LPCSG) solar cells. The best performing LPCSG cells are made by line-focus laser crystallisation of 10 µm thick ebeam silicon films on dielectric layer coated borosilicate glass. High material quality is confirmed by low defect density observed in TEM images, high carrier mobilities, and minority carrier lifetime longer than 260 ns. An intermediate dielectric layer can be SiC x , SiO x , SiN x or their combination and its properties are crucial for cell fabrication and performance. Dopants are introduced into the LPCSG cell absorber either during film deposition or diffused from doped intermediate layer during crystallisation. Light-trapping texture is formed on the exposed silicon surface by wet etching. A cell emitter is created by diffusion from spin-on-dopant source. Cell metallisation is based on point contacts between Al and cell emitter and absorber accessed through vias etched through cell layers to different depths. LPCSG cells outperformed CSG cells, with record V OC of 585 mV and efficiency of 11.7%. Efficiencies above 13% are achievable by improving light-coupling and contacting.

A variety of defect healing methods was analyzed for optimization of polycrystalline silicon (poly-Si) thin-film solar cells on glass. The films were fabricated by solid phase crystallization of amorphous silicon deposited either by plasma enhanced chemical vapor deposition (PECVD) or by electron-beam evaporation (EBE). Three different rapid thermal processing (RTP) set-ups were compared: A conventional rapid thermal annealing oven, a dual wavelength laser annealing system and a movable two sided halogen lamp oven. The two latter processes utilize focused energy input for reducing the thermal load introduced into the glass substrates and thus lead to less deformation and impurity diffusion. Analysis of the structural and electrical properties of the poly-Si thin films was performed by Suns-VOC measurements and Raman spectroscopy. 1 cm2 cells were prepared for a selection of samples and characterized by I–V-measurements. The poly-Si material quality could be extremely enhanced, resulting in increase of the open circuit voltages from about 100 mV (EBE) and 170 mV (PECVD) in the untreated case up to 480 mV after processing.

We present the calculation of the cross section and invariant mass distribution for Higgs boson pair production in gluon fusion at next-to-leading order (NLO) in QCD. Top-quark masses are fully taken into account throughout the calculation. The virtual two-loop amplitude has been generated using an extension of the program GoSam supplemented with an interface to Reduze for the integral reduction. The occurring integrals have been calculated numerically using the program SecDec. Our results, including the full top-quark mass dependence for the first time, allow us to assess the validity of various approximations proposed in the literature, which we also recalculate. We find substantial deviations between the NLO result and the different approximations, which emphasizes the importance of including the full top-quark mass dependence at NLO.

Electron beam direct write (EBDW) with a variable shaped beam writer can be applied for very low volume applications like prototyping and personalization. Together with Infineon Technologies, the Center of Competence E-Beam Lithography of Qimonda in Dresden has demonstrated the integration of an E-Beam written back end of line metal layer into a productive 220nm node microcontroller fabrication process. For this purpose an electron beam lithography unit process was developed, and all necessary steps like data prep, proximity correction, alignment and overlay processes and etching processes were reviewed. Several test wafers have been completed in fabrication and measured electrically. At first go, full electrical functionality with a yield >70% could be demonstrated.

Recent year's equipment design has enabled the combination of in situ deformation tests with near real time electron backscatter diffraction (EBSD) mapping of the microstructure evolution in the scanning electron microscope (SEM). The present work involves studies of deformation induced phase transformations in supermartensitic steel containing ∼40 vol.-% retained austenite at room temperature. The martensite formation was initiated already at low strains, and increased gradually with increasing plastic strains up to ∼10%. It was observed that the martensite formed homogeneously within the microstructure, independent of the crystallographic orientations of the retained austenite. But no new martensite variants, besides those already present in the as received condition, did form during deformation. At the same time, the mutual distribution of these variants remained approximately constant throughout the deformation process.

Crystalline silicon on glass (CSG) solar cell technology was developed to address the difficulty that silicon wafer-based technology has in reaching the very low costs required for large-scale photovoltaic applications as well as the perceived fundamental difficulties with other thin-film technologies. The aim was to combine the advantages of standard silicon wafer-based technology, namely ruggedness, durability, good electronic properties and environmental soundness with the advantages of thin-films, specifically low material use, large monolithic construction and a desirable glass superstrate configuration. The challenge has been to match the different preferred processing temperatures of silicon and glass and to obtain strong solar absorption in notoriously weakly-absorbing silicon of only 1.4 μm thickness, the thinnest active layer of the key thin-film contenders. A rugged, durable silicon thin-film technology has been developed arguably with the lowest likely manufacturing cost of these contenders and confirmed efficiency for small pilot line modules already in the 8–9% energy conversion efficiency range, on the path to 12–13%.

¶At the Deutscher Wetterdienst (DWD) an internal project named LITFASS was running to determine the representative turbulent fluxes of heat and momentum over heterogeneous land surfaces by observation and simulation. The project took advantage of the infrastructure of the Research Division at the DWD, where model research capacity is combined with the measurements made at and around the Meteorological Observatory Lindenberg.

The alternative As-precursor tertiarybutylarsine (TBAs) is used to grow (AlGa)As–GaAs heteroface solar cell structures. In a horizontal reactor (AIX200) a low growth temperature of 625°C and a low V/III-ratio of 10 was used. Solar cell structures using a arsine (AsH3)-based MOVPE process were grown in a multi-wafer reactor (AIX2600G3) using growth temperatures of 700°C and a V/III-ratio of 31. The solar cell efficiencies of both structures are 24.2% (AM 1.5 g). The obtained efficiency values are state of the art and demonstrate that TBAs can be an alternative to the more commonly used arsine with no decrease in the solar cell performance.

The paper reports on the progress of MOVPE-grown III–V epitaxial structures and tandem solar cell development. A multi-wafer reactor with a capacity of five 4-in wafers is used to grow high-efficiency, large-area tandem solar cells. The benefits of advanced tandem structures for concentrator applications based on Ga0.35In0.65P/Ga0.83In0.17As grown lattice mismatched to GaAs are discussed. In order to achieve super-high efficiencies a mechanical stack of monolithic tandem cells made from Ga0.51In0.49P/GaAs and Al0.25Ga0.75As0.02Sb0.98/GaSb is suggested.

The use of Ga/sub 1-x/In/sub x/As instead of GaAs as a bottom solar cell in a Ga/sub y/In/sub 1-y/P/Ga/sub 1-x/In/sub x/As tandem structure increases the flexibility of choosing the optimum bandgap combination of materials for a multijunction solar cell. Higher theoretical efficiencies are calculated and different cell concepts are suggested for space and terrestrial concentrator applications. Various Ga/sub y/In/sub 1-y/P/Ga/sub 1-x/In/sub x/As material combinations have been investigated for the first time and efficiencies up to 24.1% (AM0) and 27.0% (AM1.5 direct) have been reached under one-sun conditions. An efficiency of 30.0-31.3% was measured for a Ga/sub 0.35/In/sub 0.65/P-Ga/sub 0.83/In/sub 0.17/As tandem concentrator cell with prismatic cover at 300 suns. The top and bottom cell layers of this structure are grown lattice-matched to each other, but a large mismatch is introduced at the interface to the GaAs substrate. This cell structure is well suited for the use in next-generation terrestrial concentrators working at high concentration ratios. For the first time a cell efficiency up to 29-30% has been measured at concentration levels up to 1300 suns. A small prototype concentrator with Fresnel lenses and four tandem solar cells working at C=120 has been constructed with an outdoor efficiency of 23%

The reduction in oxygen contamination levels in organometallic precursors has been established as a key requirement in the metal organic vapour-phase epitaxy (MOVPE) of high brightness light emitting diode (LED) and laser devices. A number of different volatile oxygen-containing impurity species have been identified, and both physical and chemical techniques have been developed to eliminate them from a wide range of source materials to produce the next generation grade of high-purity products. In this study conclusive growth results are presented to highlight the significantly improved quality of device structures obtained when higher purity oxygen-free precursors are employed.

The investigation of the surface acidity in commercially available alumina–silicas through FTIR spectroscopy of adsorbed CO probe molecules has been reported. The modification of γ-alumina with silica led to the creation of both highly acidic Lewis and Bronsted acid sites (BASs); the former through isomorphous substitution of Si 4+ ions by Al 3+ ions at tetrahedral lattice sites; and the latter through formation of bridged hydroxy groups, similar to those found in zeolites. The relative strength and quantity of these sites reached a maximum with 40 wt.% silica content, above which the surface of the samples became silica coated and exhibited acidity approximating that of pure silica. This paper highlights (i) the suitability of CO as a probe molecule for the investigation of surface acidity, capable of differentiating between sites of very similar acid strength and/or coordination, and (ii) the enhancement of surface acidity in alumina through silica addition and subsequent formation of a mixed alumina–silica phase.

As the feature size of integrated circuits is driven to smaller dimensions the importance of the inter- and intralayer isolator capacitance in future metallization schemes becomes more pronounced. Organic polymers with low dielectric constants are one class of material choice for the replacement of SiO2. However, their successful integration into functional circuits requires new fabrication procedures. The embedded dielectric scheme offers an evolutionary path for their successful integration into a subtractive etched, aluminum-based integrated circuit. This scheme can effectively lower the total capacitance while minimally changing the rest of the metallization fabrication process. However, the non-conformal deposition of spin-on polymers requires an effective planarization process. Therefore, this paper focuses on the planarization capability of a chemical mechanical polishing process (CMP) using SiLK resin as the interlayer dielectric material. The experimental results demonstrate the high planarization capability of the CMP process using a commercially available slurry. The post-CMP degree of planarization is greater than 95% for all feature dimensions and this planarity can be achieved rapidly. SiLK dielectric coatings are therefore considered as a promising candidate to replace SiO2 in existing Al/W-based technologies.

The adsorption of non-reactive alkanethiols and cyano-terminated thiols possessing the same chain length as well as their mixtures were examined on polycrystalline gold surfaces by angle resolved X-ray photoelectron spectroscopy (ARXPS). The adsorption behavior was investigated based on the chemical shift of the S 2p peak components. Besides the expected bound state of the thiols at the surface, non-bound molecules were detected with an increasing intensity at lower take-off angles. The layer composition does not entirely reflect the solution composition and the degree of adsorption is independent of the solution composition. A preferential adsorption of the methyl-terminated alkanethiol at the polycrystalline gold surface was measured.

Line-focus diode laser is applied to advance crystalline silicon thin-film solar cell technology. Three new processes have been developed: 1) defect annealing/dopant activation; 2) dopant diffusion; 3) liquid phase crystallisation of thin films. The former two processes are applied to either create a solar cell device from pre-crystallised films or improve its performance while reducing the maximum temperature experienced by substrate. The later process is applied to amorphous silicon films to obtain high crystal and electronic quality material for thin-film solar cells with higher efficiency potential. Defect annealing/dopant activation and dopant diffusion in a few micron thick poly-Si films are achieved by scanning with line-focus 808 nm diode laser beam at 15-24 kW/cm2 laser power and 2~6 ms exposure. Temperature profile in the film during the treatment is independent from laser power and exposure but determined by beam shape. Solar cell open-circuit voltages of about 500 mV after such laser treatments is similar or even higher than voltages after standard rapid-thermal treatments while the highest temperature experienced by glass is 300C lower. Amorphous silicon films can be melted and subsequently liquid-phase crystallised by a single scan of line laser beam at about 20 kW/cm2 power and 10-15 ms exposure. Solar cells made of laser-crystallised material achieve 557 mV opencircuit voltage and 8.4% efficiency. Electronic quality of such cells is consistent with efficiencies exceeding 13% and it is currently limited by research-level simplified cell metallisation.

The efficacy and tolerance of mezlocillin and ampicillin/sulbactam were investigated in an open, comparative, multicentre study involving 96 patients. The high levels of efficacy of both ampicillin/sulbactam and mezlocillin, as previously documented in comprehensive in vitro studies, were confirmed with regard to the wide range of pathogens examined in this study. Both therapies were also associated with high clinical success rates and were well tolerated. It is worth noting that the larger number of patients suffering from chronically obstructive bronchitis apparently had no negative effects on the clinical results of the ampicillin/sulbactam therapy. In cases of nosocomial respiratory tract infections, especially those with a high incidence of β-lactamase-producing organisms, a combination including β-lactamase inhibitors may be expected to be superior to any of the ureido penicillins. The present study demonstrates that in cases of community acquired infections of the lower respiratory tract, treatment with ampicillin/sulbactam can be regarded as a suitable therapeutic alternative to mezlocillin, combining high efficacy and tolerance.

BACKGROUND: High-dose 5-FU given weekly as a 24-h infusion in combination with folinic acid (FA) has been associated with low toxicity and a high response rate. Interferon-alpha (IFN) either alone or in combination with FA has also improved treatment results by modulating 5-FU activity. We therefore initiated a randomized multicenter trial comparing the ability of FA or IFN to modulate infusional 5-FU. The statistical design using a sequential analysis allows us to report on the comparison of 5-FU/FA vs. 5-FU/FA/IFN while randomization of patients into 5-FU/FA vs. 5 FU/IFN continues. METHODS: Chemotherapy-naive patients with advanced progressive colorectal cancer and measurable metastatic lesions were randomized to receive 5-FU 2600 mg/m2 i.v. as a 24-h infusion, combined with either FA 500 mg/m2 as a 2-h infusion (A), or IFN 3 x 10(6) U s.c. 3 x/week (B), or the combination of FA plus IFN as in arms A and B (C). Treatment arms were repeated weekly for 6 weeks followed by a 2-week rest period. These 8-week cycles were administered until tumor progression. Because of the occurrence of 2 toxic deaths among the first 17 patients treated in arm C, 5-FU was reduced to 2000 mg/m2 for all patients in arm C. Sequential analysis according to Whitehead for objective response was planned with alpha = 0.05/3 and a power of 80% (beta = 0.2) to detect a difference of > or = 25% (delta = 0.25) or equivalence of response rates. For pairwise comparison of treatment arms a minimum of 30 patients per arm and a maximum of 90 patients per arm were expected in case of equivalence or difference. RESULTS: An interim analysis was performed after the first 93 of 149 randomized patients were evaluable for response and toxicity (A 31 pts, B 33 pts, C 29 pts). Despite the 5-FU dose reduction in arm C, 28% of patients experienced grade 3/4 toxicity (CTC) including diarrhea, mucositis and handfoot syndrome compared to 16% in arm A and 12% in arm B (not significant). No treatment related toxic death occurred in arms A or B, but 3 patients (10%) in arm C died of diarrhea and septicemia. Among patients treated with 5-FU/FA objective tumor response occurred in 12/31 patients (39%) (21%-56%, 95% confidence interval) (3 CR, 9 PR), no change in 13/31 (42%) and PD in 6/31 (19%) patients. Eleven of 29 patients (38%) (20%-56%, 95% confidence interval) receiving 5-FU/FA/IFN achieved complete (3 patients) or partial (8 patients) remissions, 10/29 patients (34%) had stable disease and 8/29 patients (28%) tumor progression. According to the sequential analysis the rates of objective responses observed in patients treated with 5-FU/FA or 5-FU/FA/IFN were equivalent. CONCLUSION: This interim analysis allows the conclusion that infusional 5-FU plus FA/IFN is no more active than infusional 5-FU plus FA alone. However, 5-FU/FA/IFN despite 5-FU dose reduction was associated with unacceptably high toxicity, including 10% deaths. Therefore, further investigation of this regimen is not justified. The study is continued with the comparison of 5-FU/FA vs. 5-FU/IFN.

An experiment to measure the bound β-decay of the neutron into a hydrogen atom and an electron anti-neutrino is described. Observation of such a decay would open an alternative pathway to physics beyond the Standard Model, in particular right-handed current admixtures in the weak interaction as well as the handedness of the neutrino. The experiment is planned at the through-going beam tube SR6 at the FRM2 high-flux reactor in Garching. Although the branching ratio of this decay is expected to be only 4 · 10−6 of the normal neutron β-decay [1], a sufficient decay rate due to the high flux of neutrons available for the experiment is expected. Simulations have shown that the measurement is feasible, with proper shielding being the critical factor. The experimental setup is currently being studied, testing different detection techniques for H(2s) at the TUM.

Theoretical calculations predict a higher power conversion efficiency for the combination of Ga/sub 0.35/In/sub 0.65/P and Ga/sub 0.83/In/sub 0.17/As in a tandem solar cell, compared to the more commonly used Ga/sub 0.51/In/sub 0.49/P/GaAs approach. A record conversion efficiency of 21.6% (AM1.5 g) was recently achieved for a 1.18 eV Ga/sub 0.83/In/sub 0.17/As solar cell, grown lattice-mismatched to the GaAs substrate material. This paper reports on the device characteristics of first Ga/sub 0.35/In/sub 0.65/P/Ga/sub 0.83/In/sub 0.17/As tandem solar cells based on this very promising GaInAs material. A high quantum efficiency, comparable to the lattice-matched Ga/sub 0.51/In/sub 0.49/P on GaAs approach was achieved. A power conversion efficiency of 25.5% was measured under AM1.5d spectral conditions.

Pipelines of supermartensitic stainless steels (SMSS) are used for sub-sea oil and gas transportation in the North Sea [1]. The microstructure of SMSS is in the as-received condition characterised by martensite and retained austenite. This austenite forms during inter-critical annealing, providing a metastable phase on subsequent cooling to room temperature. However, the stability of the retained austenite depends on the steel chemical composition and the applied heat treatment [2].

Hydrogen induced stress cracking (HISC) can cause critical failures in pipeline steels employed for sub-sea transportation of oil and gas [1,2]. The hydrogen, being introduced into the pipelines from the cathodic protection system, can in combination with applied stress/strain make the material susceptible to hydrogen embrittlement [2].

We investigated the extracellular and intracellular invertase activity of two Trichosporon adeninovorans strains. Both strains (SBUG 724 and CBS 2844) secrete one invertase into the medium. The external enzymes were purified by chromatography on hydroxylapatite. The molecular weight of the external invertase of SBUG 724 was found to be 650,000 and of CBS 2844 450,000. The internal invertases were separated by DEAE-cellulose chromatography. The molecular weight of the enzyme from CBS 2844 was estimated to be 125,000. In the strain SBUG 724 we found two internal invertases (Mr 230,000 and 70,000). The activity of all invertases has similar properties. The pH optimum of the reaction was determined between 5.0 and 5.2 and the temperature optimum was 60 to 70°C. The Km value for sucrose was determined to be 71 to 83 mM and for raffinosc 27 to 36 mM.

This chapter aims to draw a synthetic overview of the state of the art with regard to the evaluation of sustainable development, understood here as institutionalized processes in public authorities, in Belgium. This publication is linked to the Sustainability Impact Assessment project, and has been first presented at the EASY-ECO conference in 2005.