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LSAT (Logistics Specification and Analysis Tool) is a tool for rapid design-space exploration of supervisory controllers that steer the product logistics and orchestrate the behavior in flexible manufacturing systems. LSAT enables lightweight modeling of system resources, system behavior, and timing characteristics. The tool provides various visualizations to explore the controlled system behavior and analysis and optimization techniques to improve the system performance. Compared to existing approaches, LSAT provides concise modeling using languages tailored towards the application domain, with domain concepts are elements of the language. LSAT provides efficient performance analysis by exploiting the structure of the models. In this paper, we describe the rationale for developing LSAT and position it with respect to other performance modeling and analysis tools. We illustrate the benefits of LSAT with an example system.

Industrial domains, such as Internet of Things, Industry 4.0, and automotive, rapidly move towards autonomous connected systems. Security and privacy of these even-more connected systems demand particular attention. The whole value network serving original equipment manufacturers shall assist in addressing these concerns. System architects responsible for designing (parts) of such future systems can benefit from architectural guidance documents. For example, reference designs can help to resolve recurring architectural questions and assist in making high-level design decisions. A shared understanding of what guidance forms exist and how they differ is desired. Unfortunately, it is currently lacking.This paper surveys the state-of-the-art and state-of-practice of architectural guidance items in the automotive domain. We analyze what practitioners and researches perceive as guidance useful for addressing security and privacy concerns. To collect inputs, we conducted a survey within SECREDAS— a project comprised of 69 organizations from both industry and research domains. Based on the content of these inputs, we identified and cross-compared the following types of architectural guidance items: reference architectures, architecture frameworks, standards, protocols, and interfaces.The resulting overview and classification show practitioners which architectural guidance documents are actually used and which are relevant to consider. This paper also aims to inform discussions on architecting autonomous connected systems in general, as the need to address security and privacy concerns has a broad scope.

Design decisions are made in an early-design phase of system development. These decisions have a big impact on the resulting system design and realization. Making design decisions in this stage is a complex and risky task, because there are a lot of uncertainties regarding their impact on the system qualities. Moreover, in many cases, trade-offs have to be made when there are conflicting objectives. This paper presents a methodology to support decision making for evolutionary systems, to decide on the most suitable design. The focus is on the embedded part of a system. Information is structured with explicit relations, such that the realization of a design can be traced towards the concerns a stakeholder has for the system. This structure enables architects and designers to understand and reason about the impact of a design with a system-wide perspective. The method consists of a calibration step which imports a current design, a design exploration step in which designs are selected, and a decision step where the most suitable design is chosen. The methodology is demonstrated by exploring and revealing the trade-offs for platooning designs from the automotive domain.

Electrification of chemical industry is essential in order to keep up with the modernizing energy supply. The microwave plasma is uniquely suited to deposit high electrical power in stable molecules, to drive reactions that would otherwise only be possible at very high temperatures.

Data management planning - thinking in advance about what will happen to data produced during the research process - is increasingly required by national research funding agencies, and data management guidelines for Horizon 2020 research projects were released by the EU in December 2013 (Guidelines on Data Management in Horizon 2020). Similar guidelines have been issued by the US Department of Energy (Statement on Digital Data Management), Australia (ANDS Data Management Plans) and across many other countries.The EUDAT project exists in part to disseminate and promote best practice in data management for twenty-first century research, and to provide support for communities in adopting basic principles such as data registration, metadata creation and data movement. As part of its mission to help researchers and research communities manage and preserve their data, EUDAT works with the world-recognised Digital Curation Centre on a version of their widely-used DMPonline tool which will capture the H2020 guidelines in a data management planning tool tailored to the emerging needs of European research.EUDAT’s is building a Collaborative Data Infrastructure (CDI) as a pan-European solution to the challenge of data proliferation and associated management in Europe’s scientific and research communities. The CDI will allow researchers to share data within and between communities and enable them to carry out their research effectively. Our mission is to provide a solution that will be affordable, trustworthy, robust, persistent, open and easy to use.

Microgrids have been proposed as an attractive solution to harness the benefits offered by distributed energy resources (DERs). However, despite their advantages, microgrids introduce new challenges to electric grids. In particular, they can impact conventional protection practices in distribution systems. This is mainly due to the presence of DERs, different microgrid operational modes, as well as various network configurations. This paper will provide an up-to-date overview and analysis of the protection schemes that have been designed and/or implemented in major North American microgrid projects. A brief overview of the microgrid protection issues and potential solutions are also presented in the paper to help designers with defining protection requirements for practical microgrids.

An increased level of complex offshore load handling operations is expected due to an increased amount of floating wind turbines, remote fish farms, and autonomous shipping, and in general more advanced operations to be carried out at sea. A common problem for these applications is that both equipment and personnel have to be transported between two floating vessels at sea. An investigation of the Vessel-to-Vessel Motion Compensation (VVMC) problem may increase the efficiency and safety of such operations in the future. In this paper, a control algorithm has been developed and experimentally tested in the Norwegian Motion Laboratory featuring two Stewart platforms (SPs), an industrial robot, two Motion Reference Units (MRUs), and a Maritime Broadband Radio (MBR) used to establish a real-time wireless communication link. The resulting overall compensation error is measured to be no more than 41.9 mm during the experiments.

The industry state-of-the-art offshore motion compensation is today carried out by offshore cranes equipped with Active Heave Compensation (AHC) systems, meaning that a hanging load is positioned at a certain height above the seafloor, even though the floating vessel carrying both the crane and the load is moving due to wave disturbances. Lately, there has been an increased interest among the industry also to compensate for the movement of a secondary vessel, which indicates that a more detailed investigation of the Vessel-to-Vessel Motion Compensation (VVMC) problem is required. The primary motivation for such compensation technique is influenced by the demand for load transfer between ships during harsh weather conditions, service on floating wind turbines and fish farms, and the transportation of personnel and equipment safely between two floating vessels, for instance. In this paper, the capability of the Leica AT960 laser tracker to measure the relative position and orientation between the two moving Stewart platforms simulating the vessels movement at sea is investigated. The acquired measurements are used to carry out a real-time VVMC using the experimental lab setup in the Norwegian Motion Laboratory at the University of Agder. The obtained experimental results and motion compensation effectiveness are quantified in terms of the accuracy and real-time performance.

In order to reduce congestion and increase reliability, Southern California Edison (SCE) set forth to construct a new 500 kV transmission line. Due to right-of-way concerns, SCE needed to install a section of the new line underground, resulting in a combined cable and overhead transmission line. The finished line consists of two overhead sections separated by an underground section. The inclusion of underground cables causes the line to draw significant charging current, resulting in severe overvoltage conditions when the line is open circuited or lightly loaded. The protection package for this transmission line consists of distance protection complemented by a communications-assisted permissive scheme operating in parallel with a line current differential scheme. Because impedance-based fault locating would not be reliable for a line of this structure, we explored the use of a traveling-wave fault locater. To verify the correct operation of the proposed protection and fault locating scheme, the transmission line and its surrounding power system were modeled in a real-time digital simulator. This paper describes how to calculate line impedance and explores impedance-based and traveling-wave fault locating methods. It also discusses the protection challenges associated with operating a double-circuit transmission line as a single circuit and the challenges of a transmission line containing both overhead and underground conductors. Finally, the paper describes using real-time digital simulation to evaluate the performance of the protection system.

Relative Vessel-to-Vessel Motion Compensation (VVMC) between two floating vessels can be considered an extension of existing Active Heave Compensation (AHC), which is current state-of-the-art in the offshore industry. In this paper, the experimental results from a small-scale experimental setup of a VVMC scenario are presented. The work focuses on the kinematics related to VVMC, sensor accuracy of Motion Reference Units (MRUs), and the communication delay related to wireless transmission of MRU data between two floating vessels. The accuracies of the MRU sensors are good and verified to be less than 5% of the heave amplitude. The wireless communication link had a typical time-delay of 8ms. The presented work demonstrates the 3D-kinematics related to VVMC using homogeneous transformations, and the experimental results show that wireless transmission of MRU data is a viable solution for offshore VVMC scenarios.

This paper introduces a formal modeling approach for compositional specification of both functionality and timing of manufacturing systems. Functionality aspects can be considered orthogonally to timing aspects. The functional aspects are specified using two abstraction levels; high-level activities and lower level actions. Design of a functionally correct controller is possible by looking only at the activity level, abstracting from the different execution orders of actions and their timing. As a result, controller design can be performed on a much smaller state space compared to an explicit model where timing and actions are present. The performance of the controller can be analyzed and optimized by taking into account the timing characteristics. Since formal semantics are given in terms of a (max, +) state space, various existing performance analysis techniques can be used. We illustrate the approach, including performance analysis, on an example manufacturing system.

Sustainable energy generation by means of wind or from solar radiation through photovoltaics or concentrated solar power will be a significant part of the energy mix in 2025. Intermittency (due to e.g. day/night cycle) as well as regional variation of these energy sources requires means to store and transport energy on a large scale. A promising option is creating artificial solar fuels (or CO2 neutral fuels) with sustainable energy, which can easily be deployed within the present infrastructure for conventional fossil fuels.

In his paper the physical properties and mathematical models of a semi-active magnetorheological (MR) damper is studied. The considered models are the Dahl model and Bouc-Wen model. The parameters for these models are found by using a firefly optimization algorithm that minimizes the difference between experimental and simulated data. The objective of his paper is to compare different mathematical MR-damper models with the experimental data. The simulation results illustrate he effectiveness of he proposed optimization algorithm.

The option to acquire compact polarimetry (CP) data will be available on all RADARSAT Constellation Mission (RCM) imaging modes. Relative to RADARSAT-2's (R2) polarimetric data, RCM's CP data can be acquired over wider swaths (up to 500 km) but offer reduced polarization diversity. In addition, the nominal signal-to-noise ratios (SNR) for RCM modes fall short of those for R2 polarimetric modes. This paper presents results of an ongoing study into the utility of RCM CP data in support of the mapping and monitoring of freshwater ice cover. Specifically, the effects of the loss in polarization diversity and radiometric resolution on the information content regarding freshwater ice cover properties and processes are assessed. The results indicate that RCM CP data will offer good potential in support of spring breakup monitoring and ice type mapping. On the other hand, RCM CP data are expected to be of limited utility for freeze-up monitoring.

Summary form only given. Intermittent sources of renewable energy that are increasingly becoming available along with forthcoming depletion of fossil fuels has recently stimulated the research interest in CO2 neutral fuels. More precisely, CO2 capture and utilisation in a closed loop carbon cycle are envisaged. Renewable energy is thereby stored through CO2 activation, dissociation and further hydrogenation in chemical fuels. Such hydrocarbon fuels of high energy density would fit into the existing transport and energy infrastructure. Plasma-processing of CO2 in the gas phase under non-equilibrium conditions is thereby considered as promising substitute to conventional routes to specifically tackle the rate-limiting dissociation into CO. To become an economically viable alternative to conventional fuel processing routes, the energy efficiency of the CO2 processing step has to be maximised. This in turn requires a better understanding of CO2 activation channels and reaction mechanisms in plasma-assisted processes. For this purpose two model systems have been studied: (i) a microwave (MW) driven plasma at sub-atmospheric pressures and relevant flow-rates of tens of liters per minute CO2, and (ii) a mid-frequency (kHz range) dielectric barrier discharge (DBD) operated at atmospheric pressure. Energy efficiencies as high as 60 % were established for the MW plasma using mass spectrometry. These experiments confirmed the importance of low specific injected energies (around 1 eV/molecule CO2) as established earlier. However, plasmadiagnostic studies on the DBD system revealed that the reduced electric field as plasma parameter is as essential as the injected energy. Typically, the energy efficiency of DBD processes in CO2 fall short of 10 %. The densities of CO and byproducts, among them O3, were established by FT-IR absorption spectroscopy. Time-resolved optical emission and infrared laser absorption spectroscopy were used to deduce (electronic) excitation processes as well as to distinguish potential gas phase and surface processes. It transpires that the conversion process in DBDs is significantly determined by electronic excitation and ionisation processes. Moreover slow formation and depletion rates of CO observed in pulsed DBDs suggest a nonnegligible contribution of surface processes.

Plasma-enhanced chemical vapour deposition (PE-CVD) of silica-like layers at atmospheric pressure onto large-area polymeric substrates has been shown to yield high-quality barrier layers. A key requirement is to achieve a diffusive discharge mode in industrially relevant air-like gas mixtures (N2/O2/Ar) without admixtures of Helium. An electronic stabilisation enables high discharge currents (several A) to be achieved.

Resource planning is the greatest challenge cloud computing service providers face, because it is difficult to predict future resource demands. Fluctuation in demand coupled with inadequate resource planning causes over-or under-utilization of many resources, resulting in a loss of revenue that has created the need for a more efficient market model. The creation of an Information Technology Exchange (ITE) is the long-awaited solution to the resource-utilization problem. Trading cloud resources as commodities-futures, forward, spot, and swap contracts-would allow service providers to predict consumption, meet future workload needs, and increase revenue. The prepackaged and/or atomic resource bundles, called Information Technology Exchange Traded Resources (IT-ETRs), are modeled after the Exchange Traded Funds (ETFs) of the financial market. In the experiment described in this paper, the trading of cloud resources as commodities in an exchange improves utilization.

River ice has an important effect on natural processes and human activities in northern countries. Current models for estimating river ice thickness are mostly based on environmental data. They require several inputs and yield only a global estimate of ice thickness for a large heterogeneous area. Attempts have been made intending to retrieve river ice thickness from remote sensing using monopolarized C-band radar data. No reliable maps of ice thickness have been produced. In this paper, the potential of polarimetric synthetic aperture radar (PolSAR) data for estimating river ice thickness is demonstrated, and a river ice thickness retrieval model is proposed. The C-band SAR images used in this paper were acquired by Radarsat-2 in the winter of 2009 over the Saint-Francois River (Southern Quebec), the Koksoak River (Northern Quebec), and the Mackenzie River (Northwest Territories) in Canada. Field campaigns were carried out to obtain ice thickness validation data at 70 locations. Polarimetric entropy was used to obtain ice thickness estimates. This approach results in spatially distributed ice thickness maps for selected ice types.

Many companies use business intelligence (BI) to improve organization performance. BI relies on the data in the enterprise information system (EIS), and in order to guarantee data freshness, this data needs periodic updating. The EIS contains data warehouses frequently residing in the many machines in at least one data center. Many jobs, also called tasks or operations, run to bring data into the data warehouses. Some jobs may depend on others, whereas others may be independent. Traditionally, these jobs are scheduled based on the dependency but not on the critical path; thus, the conventional scheduling algorithm is nonoptimal. This leads to excessive runtime and nonoptimal usage of resources. Data processing jobs in the data warehouse system involve many resources, so it is necessary to find the best job-scheduling methodology. According to existing literature, job scheduling in the distributed data warehouse system has not been studied. This paper discusses how to use the historic data and critical path to generate an optimal scheduling plan involving the minimum number of machines while guaranteeing shortest runtime. Experimental results show the optimal scheduling algorithm can reduce runtime and optimize usage of resources.

The multi-polarized and polarimetric capabilities of RADARSAT-2 are evaluated to enhance river and lake ice monitoring. Multi-year time series of polarimetric images for selected rivers and lakes in north-western Canada are analyzed for their information potential. Meteorological and geophysical field measurements support the interpretation of polarimetric imagery. Statistically estimated thresholds for selected polarimetric parameters are used in unsupervised classification and subsequent ice mapping.

The network and nature of hydrogenated amorphous silicon (a-Si:H) are conventionally interpreted in terms of a continuous random network (CRN) of Si-Si bonds, weak Si-Si, Si-H bond and dangling bonds. A CRN requires that the smallest anisotropic features like dangling bonds and bonded hydrogen are randomly distributed and reside as isolated configurations in the network. However, in recent years more and more theoretical and experimental evidence have been found that both the isolated dangling bond and the isolated hydrogen are not present in the a-Si:H network. To the contrary, all studies come to the conclusion that the real nature of the a-Si:H is to contain more local structural order than expected from a CRN. These insights offer new opportunities to revisit the origin of several properties of a-Si:H, which are up to now explained within the framework of the CRN model. In this contribution we will discuss that many diagnostics like nuclear magnetic resonance, positron annihilation, small angle x-ray spectroscopy, density analysis and infrared spectroscopy on a-Si:H consistently demonstrate that a-Si:H exhibits an anisotropic network. In dense disordered networks the hydrogen predominantly resides in hydrogenated divacancies, whereas for less dense networks the hydrogen predominantly resides in poly-vacancies up to nanosized voids. We will discuss that hydrogenated divacancies in a disordered network contribute to the amorphous nature of a-Si:H and its electronic structure like the band gap, gap tails and the defect gap states.

The expanding thermal plasma, which is a promising technique for microcrystalline silicon (μc-Si:H) thin-film deposition because of its high growth rates over large areas, witnesses, so far, specific challenges in the deposition of device-grade μc-Si:H material. The μc-Si:H films show post-deposition oxidation, caused by an insufficient amount of (dense) amorphous tissue between the grains, resulting in low solar cell efficiencies. Atomic hydrogen, which is crucial for the formation of μc-Si:H films, is hypothesized to be responsible for this lack of amorphous tissue because of its ability to etch amorphous silicon (a-Si:H) by insertion in Si-Si bonds. Therefore, we studied the interaction of atomic H with thin a-Si:H films. Results show that etching does not compete with film growth, as etch rates are one order of magnitude lower than deposition rates. Furthermore, atomic H cannot be held responsible for the poor quality of amorphous tissue present in ETP-grown μc-Si:H, as the H up-take takes mainly place in divacancies.

Policies and economics in social networks are intertwined with a physical system. Research on socio-technical systems, including eco-cities, energy systems, transport infrastructures and supply chains, tries to combine the technical engineering discipline for the physical system with the social perspective on consumer behaviour. However, efforts to develop an ontology, i.e. a shared formal conceptualisation, for socio-technical systems have so far focussed mostly on the technical part of the system. In this paper a first step is made towards inclusion of consumer acceptance by including views from communication science and psychology. This takes advantage of an extensive body of work and enables co-operation and successful communication between different fields of research. This eventually may lead to a more societal realistic ontology of socio-technical urban energy systems for eco-cities. The rationale for the approach and preliminary results of the ontology are explained using the example of a low-carbon city regarding consumer acceptance of new energy technologies.

Aluminum oxide films (Al 2 O 3 ) synthesized by atomic layer deposition (ALD) provide an excellent level of surface passivation of n−, p−, and heavily doped p-type crystalline silicon (c-Si). It has been shown that a negative fixed charge density in the order of 1012–1013 cm−2 can be present at the interface of Al 2 O 3 with c-Si, inducing a high level of field-effect passivation. In this contribution we report on results obtained by two complementary, contactless techniques to investigate the field-effect passivation for the Al 2 O 3 /c-Si case: optical second-harmonic generation (SHG) and corona charging. From an extensive data set on Al2O3 thin films, we demonstrate that the combination of SHG and corona charging offers the advantage of probing the presence of fixed charges at the interface non-intrusively (SHG) and of extracting the fixed charge density quantitatively (corona). These two techniques are therefore powerful tools for investigating the mechanisms responsible for the passivation properties of thin films.

Recently, we have demonstrated that ultrathin (≪30 nm) films of Al 2 O 3 synthesized by (plasma-assisted) atomic layer deposition (ALD) provide an excellent level of surface passivation of c-Si which may find important applications in (high-efficiency) solar cells. In this contribution, the Al 2 O 3 passivation mechanism has been further elucidated by the contactless characterization of the c-Si/Al 2 O 3 interface by optical second-harmonic generation (SHG). SHG has revealed effective field-effect passivation of the c-Si surface caused by a negative fixed charge density of 5×1012 cm−2 in an annealed, 11 nm thick Al 2 O 3 film while it is on the order of 1011 cm™2 in the as-deposited film which shows negligible passivation. A comparison with SHG measurements on a 84 nm thick a-SiN x :H film treated in a conventional firing furnace has revealed the presence of a positive fixed charge density of 2×1012 cm−2 which further corroborates the SHG analysis and results.

As the manufacture of most crystalline silicon solar cells involves various high temperature processes, a good thermal stability of the surface passivation is essential. In this paper we demonstrate the thermal stability of the c-Si surface passivation by atomic layer deposited Al 2 O 3 during a firing process as applied for screen printed solar cells. The initial outstanding surface passivation quality, provided by both Al 2 O 3 and Al 2 O 3 /a-SiN x :H stacks, remained high after firing as indicated by effective surface recombination velocities ≫ 14 cm/s for 2 Ωcm n-type silicon wafers.

This paper presents results from laboratory experiments performed in order to evaluate different methods for quality control of polymeric insulated HVDC cables. In this work, we have investigated the effect of short term (24 h) DC stress followed by rapid grounding of the cable. This is comparable to a voltage step of -U0 at the point of grounding ,and depending upon the cable length, a step of up to -2 U0 at the far end. Laboratory experiments were performed on a 200 m long 12 kV XLPE cable with a metallic needle inserted 2.6 mm into the 4 mm thick insulation at one end of the cable. The cable has no outer metallic screen and was wound on a cable drum. Aluminium foil was used as screen between the layers. The far end of the cable was either an open end or terminated with the wave impedance of the cable. The rate of voltage reduction was measured using an RC filter with a voltage divider. The time variation of voltage along the cable after grounding was calculated using an EMTP model. Tests were performed at different DC voltage levels in the range of 55-85 kV. In the case of 70 kV DC pre-stress for 24 hours, 260 groundings were needed for breakdown with a needle placed close to the short circuiting site. With a needle at the far end 500 abrupt groundings were needed. Even though the far end was exposed to oscillations of up to twice the applied voltage due to reflections, approximately twice the number of groundings was needed before electric breakdown occurred. Close to the grounding, the voltage slope was measured to 260 kV/mus. At the far end, the voltage slope was 107 kV/mus. Thus a rapid voltage variation appears to be more critical for breakdown initiation than the amplitude of the transients.

In this contribution it will demonstrated that Al 2 O 3 films synthesized by plasma-assisted atomic layer deposition are a very interesting low temperature solution for the passivation of highly and lowly doped p-type c-Si and lightly doped n-type c-Si. From experiments it will be shown that the excellent surface passivation by Al 2 O 3 can for a large part be attributed to a high fixed negative charge density in the film on the film-substrate interface. The implications of this high fixed negative charge density on the surface passivation of both n- and p-type c-Si will be addressed.

Atomic layer deposition (ALD) is a thin film growth technology that is capable of depositing uniform and conformal films on complex, three-dimensional objects with atomic precision. ALD is a rapidly growing field and it is currently at the verge of being introduced in the semiconductor industry. Recently it has been recognized that the method has also applications in many other areas relying on thin films including the area of photovoltaics. In this contribution the basics and key features of the ALD method will be described focusing especially on the potential of the method in solar cell manufacturing. It will be shown that the method is of relevance for first, second and third generation solar cells.

This paper describes the prelim inary results of a study into the potential of images from the Medium Resolution Imaging Spectrometer (MERlS) for the mapping and monitoring of aspen defoliation in Canada. Information relating to aspen defoliation supports environmental and sustainable development initiatives. More specifically, the information needs relate to the location, extent and severity of defoliation events. Our results indicate that with the help of MERIS images, the assessment of location and extent of defoliation is straightforward but the assessment of defoliation severity is challenging. MERIS derived defoliation information products offer advantages over conventional defoliation maps that are produced on the basis of aerial surveys.

In order to reduce the costs of thin-film silicon solar cell production, a manufacturing concept in which amorphous silicon (a-Si) solar cells are produced in a roll-to-roll manner on a temporary metal substrate (temporary-superstrate process) has been introduced in the Helianthos Project. Later in the process the device is transferred to a permanent plastic substrate on which cells are monolithically series connected, resulting in PV modules. In the Helianthos pilot line, modules with efficiencies above 7% are obtained on 1-foot-wide foil. On 30times30 cm/sup 2/ modules, initial efficiencies of 5.7% have been reached, while 60 cm/sup 2/ modules cut from the 35 cm wide foil have reached stabilized efficiencies of 5.8%. Lab modules with the deposition of a-Si in a batch process on roll-to-roll deposited SnO/sub 2/, have reached stabilized efficiencies of 6.7%. In order to increase efficiency, amorphous/microcrystalline (a-Si/muc-Si) tandem solar cells have been implemented in the temporary-superstrate process to fabricate flexible, lightweight tandem modules with monolithic series integration. A first module with an aperture area efficiency of 8.6% has been presented earlier. At present, an initial aperture area efficiency of 9.4% has been reached on a 60 cm/sup 2/ module

The expanding thermal plasma (ETP) is a novel plasma technique currently used by several solar cell manufacturers for the deposition of silicon nitride antireflection coatings on (multi-) crystalline silicon solar cells. In this paper we will show that the ETP technique is versatile and can be used for the deposition of silicon nitride, silicon dioxide and hydrogenated amorphous silicon with a good level of surface passivation. In this way the ETP technique can meet the future PV demands with respect to the decrease in wafer thickness and the use of n-type material that requires good electrical and optical quality thin films at both the front and the back side of the solar cell.

This paper describes a novel optical diagnostic that was recently introduced to the field of Si-based thin films for probing defect states such as dangling bonds in a-Si:H. This diagnostic is based on the cavity ringdown spectroscopy (CRDS) technique. When applied in situ or real time during film growth it can provide new insights into the a-Si:H film properties as well as into the fundamental surface processes during growth. In this paper the CRDS technique is described and both the ex situ application on as-deposited a-Si:H films as well as the in situ application during a-Si:H film growth are presented.

In this paper, we briefly preview and demonstrate how the technical improvements included in RADARSAT-2 will impact the system's potential utility for 32 applications in the fields of agriculture, cartography, disaster management, forestry, geology, hydrology, oceans, and sea and land ice.