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Urban parks are often designed and renewed using standardized models that fail to incorporate the different functions and services required by the local communities served. Furthermore, when the citizens are involved in co-design, the participation processes are seldom fully inclusive, and the results are not representative of the entire local community. The paper starts from these considerations for developing an innovative participatory design method to renew urban parks. This method simultaneously uses multiple and alternative participation tools for adapting to the different technical skills of the citizens and to their inclinations. Furthermore, it entails the analysis and interpretation of the expectations of the local community in light of the urban green network. The method uses the conceptual framework of the SWOT analysis and the Trochim's concept mapping for developing a card game playable face to face or online. The results of the card game are processed using the statistical analysis to identify the main design themes (the clusters), and to split the participants' suggestions into different design alternatives. Successively, the participants vote these alternatives for selecting the renewal design respondent to the local community's needs.

Immobilising microalgal cells has been proposed as a process solution to overcome the barriers associated with the implementation of microalgae for wastewater remediation. This work evaluated the performance and remediation mechanisms of immobilised microalgae for continuous wastewater treatment under varying hydraulic retention times (HRT). Three domestic secondary wastewaters with differing concentrations of orthophosphate (PO4-P), ammonium (NH4-N) and nitrate (NO3-N) were treated by Scenedesmus obliquus immobilised within 2% calcium alginate. Trials were run in continuous operation at HRTs of 3, 6, 12 and 20 h. Removal rates for PO4-P improved with increasing HRT, with minimum residual concentrations of 0.3-3.1 mg center dot L-1 observed at 3 h and 0.01-0.2 mg center dot L-1 at 20 h. Ammonium remediation was not linked to HRT or NH4+ concentration with minimum residual concentrations of Funding Agencies|Engineering and Physical Sciences Research Council (EPSRC) of the STREAM Industrial Doctorate Centre; Anglian Water; Severn Trent Water; Scottish Water

The produced nitrogen oxides from the biological treatment of swine and dairy anaerobic supernatant are evaluated. The quantification of the emissions has been conducted in a continuous way and coupled with batch tests to determine the mechanisms of formation. Using a continuous monitoring system, N2O and NO forms are present in higher quantities than NO2. The elevated emissions are linked with the increment of the influent nitrogen load both in the daily variations and in the long period. The NH4-N and NO2-N accumulations are recognized as the main parameters which determine the great nitrogen oxide emissions even at dissolved oxygen concentration of around 2 mgL(-1). The nitrogen oxides' impacts are between 0.0034 and 0.0044N% for the N2O and between 0.0020 and 0.0026N% for NO. A strict dependence between the N2O and the oxidation reduction potential is found.

This paper deals with the evaluation of total nitrogen (TN) removal from zootechnical wastes in a pilot scale reactor, treating digested supernatants by biological way. The high performances in terms of total nitrogen removal by nitrites, greater than 95%, enabled to design a medium scale treatment platform, by combining the anaerobic digestion (AD) and dewatering (DW) units with the alternate cycles (AC) biological process for pig and cattle supernatants. Theoretical mass balances carried out on maximum loading conditions allowed to define an optimal process chain and its sizing. Influent and effluent main parameters were determined for each operation unit, defining a final TN value for pig slurry equal to 14.1 g d -1 head -1 in the dewatered amount and 12.3 g d -1 head -1 from the AC reactor, besides an inner TN load of 49.6 g d -1 head -1 . Concerning the cattle slurry treatment, the DW process gained a TN removal of 74%, allowing the AC process to remove the remaining amount of TN of about 30.1 g d -1 head -1 . An evaluation of the reliability of a fermentation process to support the anoxic phase of the biological process was further investigated.

This paper involves the retrofitting of a real municipal wastewater treatment plant (WWTP) of 6600 population equivalent (PE), from a traditional biological process to a predenitrificationalternating cycles (PreD-AC) technology, defining a hybrid reactor. The application was investigated for 11 months, from the upgrading in October 2009 to September 2010. The pro- cess optimization allowed to reach high standards of effluent's quality, with total nitrogen (TN) and ammonia (NH4-N) con- centrations lower than 15 and 1 mg L 1 , respectively. Moreover, the flexibility and automatic control of the process guaranteed an energy consumption decrease of17%, witha specificenergyconsumptionof0.18 kWhPETN 1 d 1 asan average value.Areduction of 20% was reached by comparing the sludge amounts disposed in landfills in 2009 and 2010.

The paper describes the main features of the Superconducting Magnets Power Supply to generate the toroidal and poloidal magnetic fields in JT-60SA tokamak, with special regard to coil current regulation mode and magnets protection.

A 170 GHz, 2 MW, steady-state gyrotron is being developed in collaboration between European research associations and industries to be used for the electron cyclotron resonance heating (ECRH) system of ITER, the gyrotron is presently in the prototype state. EFDA entrusted ENEA with the design of a new power supply for the gyrotron's body; in which, the traditional power vacuum tubes are replaced with solid-state components (IGBT); furthermore ENEA had the task of developing the new body power supply (BPS), following the initial conceptual design. The BPS is formed by 50 identical bidirectional (in current) modules, connected in series; the BPS's control system regulates the output voltage by changing the modulation index. OCEM Spa, under ENEA's supervision, has manufactured the BPS. Tests, done at the start of this year, showed the substantial agreement between the initial technical specifications and the values achieved. Particularly the ramp-up/down-emergency time (50–10 μs), the accuracy (±0.5%), the sine wave modulation (45–20 kV at 5 kHz) and the maximum phase shift ( In the article, the new stair-way modulation (SWM) scheme will be sketched and the test results will be described in detail.

The activities in Europe towards the development of the EC power sources for ITER are centered on the development of a 170GHz, 2MW, CW coaxial cavity gyrotron of collector potential depressed (CPD) type. A gyrotron with a higher unit power than the ITER reference (I MW) would yield a reduction of the installation costs, a more compact launcher design and, if required, an increase of the power delivered through one port. Tests proving the principle were successfully performed on a short-pulse experimental gyrotron delivering up to 2.2 MW in single mode. Following this success, a coordinated and fully consistent programme of development has been launched. The first industrial 2 MW prototype is now at an advanced stage of construction. The associated superconductive magnet producing 6.86 T on the cavity axis is also being procured. Dummy loads suitable for short and CW operation are also part of the development effort. Finally, a new EC test facility, with the features necessary for the testing of the gyrotron up to full power in CW, has been established and includes a fully solid-state power supply system. (c) 2007 Published by Elsevier B.V.

Fusion Advanced Studies Torus (FAST) aims to contribute to the exploitation of ITER and to explore innovative DEMO technology. FAST has been designed to study, in an integrated scenario: (a) relevant plasma-wall interaction problems, with a large power load (P/R ∼ 22 MW/m; P/R2 ∼ 12 MW/m2) and with a full metallic wall; (b) to tackle operational problems in regimes with relevant fusion parameters; (c) to investigate the non-linear dynamics of fast particles (alpha like) in burning plasmas. FAST will operate on a wide parameters range, namely in high performance H-mode (BT ∼ 8.5 T; IP ∼ 8 MA) as well as in advanced Tokamak operation up to full non-inductive current scenario (IP ∼ 2 MA). The main heating is based on 30 MW ICRH, but the ports have been designed to allocate up to 20 MW of 1 MeV NNBI. Helium gas at 30 K is used for cooling of the full machine, a preliminary analysis shows the possibility of realizing FAST with a complete superconductor set of coils. An innovative active system is under development to reduce and to control the magnetic ripple. Tungsten (W) or liquid lithium (L–Li) has been chosen for the divertor material plates and the code EDGE2D has been used to optimize the divertor geometry.

A conceptual design and feasibility study has been carried out for a fully solid state Body Power Supply providing the necessary performance required for the modulation of RF power from CW, high power gyrotrons. The selected solution, based on the Pulse Step Modulation concept, is expected to yield cost and operational advantages compared to systems based on vacuum tubes. A second phase for the manufacturing of a full size unit and its testing on a power gyrotron is now in progress.

In the frame of development of the ITER electron cyclotron wave (ECW) system, a two MW CW coaxial cavity gyrotron will be developed during the Sixth Framework Program (2003-2006). Such development relies on the availability of a test stand capable of providing the electrical energy and cooling capacity. This test stand will possibly be used, in a later stage, for the component test of the ITER ECW system. This paper will first present the main parameters of this new coaxial gyrotron. Then we describe the test stand itself, including the general requirements for testing and evaluating the behaviour of the RF source and then a description of the electrical system design. Compared to the ITER reference design, the test stand emphasises the requirement of flexibility, which is necessary during the development of the gyrotron. The additional electrical equipment is included in the overview of the electrical system. The cooling system will be an important part of the design study. Indeed, the design efficiency of such a depressed collector gyrotron is approximate to 50%, implying > 4 MW of continuous heat dissipation and evacuation by the cooling equipment. The specifications of the cooling system must also comply with ITER reference design values. (C) 2003 Published by Elsevier B.V.

FAST is a new machine proposed to support ITER experimental exploitation as well as to anticipate DEMO relevant physics and technology. FAST is aimed at studying, under burning plasma relevant conditions, fast particle (FP) physics, plasma operations and plasma wall interaction in an integrated way. FAST has the capability to approach all the ITER scenarios significantly closer than the present day experiments using deuterium plasmas. The necessity of achieving ITER relevant performance with a moderate cost has led to conceiving a compact tokamak (R = 1.82 m, a = 0.64 m) with high toroidal field (B(T) up to 8.5 T) and plasma current (I(p) up to 8 MA). In order to study FP behaviours under conditions similar to those of ITER, the project has been provided with a dominant ion cyclotron resonance heating system (ICRH; 30 MW on the plasma). Moreover, the experiment foresees the use of 6 MW of lower hybrid (LHCD), essentially for plasma control and for non-inductive current drive, and of electron cyclotron resonance heating (ECRH, 4 MW) for localized electron heating and plasma control. The ports have been designed to accommodate up to 10 MW of negative neutral beams (NNBI) in the energy range 0.5-1 MeV. The total power input will be in the 30-40 MW range under different plasma scenarios with a wall power load comparable to that of ITER (P/R similar to 22 MW m(-1)). All the ITER scenarios will be studied: from the reference H mode, with plasma edge and ELMs characteristics similar to the ITER ones (Q up to approximate to 1.5), to a full current drive scenario, lasting around 170s. The first wall (FW) as well as the divertor plates will be of tungsten in order to ensure reactor relevant operation regimes. The divertor itself is designed to be completely removable by remote handling. This will allow us to study (in view of DEMO) the behaviour of innovative divertor concepts, such as those based on liquid lithium. FAST is capable of operating with very long pulses, up to 170s, despite being a copper machine. The magnets initial operation temperature is 30 K, with cooling provided by helium gas. The in vessel components, namely FW and divertor, are actively cooled by pressurized water above 80 degrees C. The same water is also used to bake the vacuum vessel. FAST is equipped with ferromagnetic inserts to keep the toroidal field magnet ripple down to 0.3%.

The treatment of industrial liquid wastes is placed in a wide context of technologies and is related to the high variability of the influent physical–chemical characteristics. In this condition, the achievement of satisfactory biological unit efficiency could be complicated. An alternate process (AC) with aerobic and anoxic phases fed in a continuous way was evaluated as an operative solution to optimize the performance of the biological reactor in a platform for the treatment of industrial liquid wastes. The process application has determined a stable quality effluent with an average concentration of 25 mg TN L−1, according to the law limits. The use of discharged wastewaters as rapid carbon sources to support the anoxic phase of the alternate cycle, realizes a reduction of TN of 95% without impact on the total operative costs. The evaluation of the micro-pollutants behaviour has highlighted a bio-adsorption phenomenon in the first reactor. The implementation of the process defined 31% of energy saving during period 1 and 19% for the periods 2, 3 and 4.

This study aims to examine the feasibility of chemical, physical and biological processes on municipal landfills leachates, to mainly evaluate Nickel (Ni) and Chrome (Cr) removal. Flocculation/coagulation methods were investigated on laboratory scale, by dosing ferric chloride (FeCl3) and aluminium polychloride to three leachates, at a natural pH of 8. The oxidation treatment with sodium permanganate (NaMnO4), applied on the leachate with higher metals content, defined an increment of Ni (from 9 to 50%) and Cr (from 31 to 80%) removals, compared with the previous chemical treatments. Further, the metals biosorption capacity on the biomass flocs was investigated in a pilot scale membrane bioreactor, previously tested on laboratory scale. The different percentages of added leachate showed efficiencies up to 93% for Cr and 58% for Ni, defining the different removal roles of the adsorption and of the membrane layer effect.

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The capability of the poloidal field coil system, as presently designed, to provide an effective vertical stabilization of the plasma in the IGNITOR machine has been investigated using the CREATE-L response model. An optimization of the vertical position control strategy has been carried out and the most effective coil combination has been selected to stabilize the plasma while fulfilling engineering constraints on the coils and minimizing the required power and voltage. The growth rate of the vertical instability and the power required by the active stabilization system has been estimated with this model. The possible failure of the relevant electromagnetic diagnostics has been taken into account, evaluating the robustness of the plasma position reconstruction strategy. A realistic description of the power supply system has permitted to carry out the optimization of the proportional-integrative-derivative (PID) controller, both with a voltage and a current loop control scheme. An assessment of the requirements for the plasma cross section shape control has been carried out considering perturbations of the plasma global parameters independent of each other and showing that the undesired shape modification rejection is possible with the present PFC and power supply system. The PF coils have been rated relative to their capability to restore shape modifications due to different plasma disturbances. The most effective coil combination, that minimizes recovery time and voltage required, has been identified. (C) 2007 Elsevier B.V. All rights reserved.

(#NP1.010) Bibliographic Code: 2006APS..DPPNP1010V

To properly regulate currents inside IGNITOR poloidal (PFC) and toroidal (TFC) field coils a system of 15 thyristor AC/DC converter has been designed. The total electrical power drawn by the 400 kV grid has been minimized performing a multi-steps iterative optimization process. In this way the most appropriate current distribution within each PFC has been identified and the coil geometry modified, easing the requirements on the power supplies and on the adopted materials. A specific design has been carried out for each AC/DC converter to minimize the requested reactive power. As a result the total installed power has been reduced from about 3300 MVA down to 2400 MVA

In ITER, EC heating and current drive (H&CD) is foreseen not only as a principal auxiliary system for plasma heating and as assist for plasma start-up, but is considered essential in meeting the key requirement of neoclassical tearing mode (NTM) stabilisation, by localized current drive. In the reference ECH design, ITER requires a total of 20 MW/CW power at 170 GHz using gyrotrons with a unit power of 1 MW. A higher power per unit (2 MW/gyrotron) would result in a strong reduction of the cost of the whole ECRH system, and would also relax the room constraints on the launcher antenna design. In view of the capability of coaxial cavity gyrotrons demonstrated with short pulse experiments at FZK, the European Fusion Development Agreement (EFDA) has started in 2003 the development of an industrial 170 GHz 2 MW/CW coaxial cavity gyrotron, in a collaborative effort between European research associations CRPP/EPFL, FZK, TEKES and Thals Electron Devices (TED). The development plan includes three steps to reach successively 2 MW/1s, 2 MW/60s and finally 2 MW/CW operation. The procurement of the first prototype is in progress and it scheduled to be delivered during the first quarter of 2006. The experimental tests of the prototypes will be carried out at CRPP/EPFL, where an ITER relevant test facility is presently under construction and will be achieved during the second half of 2005. The test facility is designed to be flexible enough, allowing the possible commissioning of tubes with different characteristics, as well the tests of the launcher antenna at full performances.

A 170 GHz, 2 MW, steady state gyrotron is being developed in a collaboration between European research associations and industries to be used for the electron cyclotron resonance heating (ECRH) system of ITER, the next step in nuclear fusion research. The gyrotron is presently in the prototype state. For the test facility dedicated to the testing of this gyrotron, new power supplies need to be procured. A feasibility study was performed aimed at using new designs based on present day techniques and at performing and constructing a prototype for further testing and evaluation. The prototype BPS (body power supply) which is connected to the body of the gyrotron is now in an advanced stage of construction and the first test results are in close agreement with the design objectives of the feasibility study

In the Frascati Tokamak Upgrade (FTU) machine, there are the following coils: the main transformer coil, the preprogrammed vertical field coil, and the feedback coil. In order to maximize the number of ports for diagnostics apparatus and additional RF heating, FTU has been designed without a massive cupper shell. Plasma displacements due to preprogramming failures or disruptions will be recovered by the vertical field generated by the coil. The plasma current is feedback-controlled by regulating the transformer current. To study the control laws and to optimize the regulation gains, a computer code based on the CSMP III (continuous system modeling program) has been used. >

A modification of the FTU tokamak (toroidal field BT = 8T, plasma current IP = 1.6MA, minor radius a = 0.3m, major radius R = 0.93m) is proposed in order to extend the FTU operation to strongly shaped plasmas (FTU-D: R = 1m, a = 0.18 - 0.2m, elongation = 1.6, triangularity up to = 0.8). FTU has a circular vacuum vessel and was built to produce circular plasmas, however unbalancing the currents in the windings of the air core transformer a plasma shaping can be produced. Single Null (SN) and Double Null (DN) equilibria have been studied with a maximum current in the range 0.350-0.450 MA. The scientific aim of the project is the investigation of the advanced tokamak operation, characterised by the simultaneous achievement of high (normalised beta) and high bootstrap current fraction ( fB) in regimes with high-energy confinement obtained by current and pressure profile control. The main features of FTU-D, with respect to other existing tokamaks, are the high magnetic field ( BT = 5 - 2.5T), the high density and aspect ratio value (A = R/a = 5-6) and the possibility of investigating regimes with dominant electron heating.

The production of steel strips and plates is usually performed with processes during several hours in plants more than 1400 meters long. In order to reduce investment and production costs, a continuous process during only 15 minutes has recently been set in Italy in an innovative plant (8 times shorter than usual) where in addition power requirements and ecologic impact are lighter. Such a compact arrangement has been possible by means of inductive reheating facilities, that maintain the strip hot, i.e. with both a liquid core and in fully solidified state. The new line-up (thin slab cast rolling machine, coilerfurnace, four-high stands finishing mill) is easily adaptable to different steels and enables a cost favourable hot strip production even with reduced quantities of product. thanks to the inductive reheating facilities. This paper will present the FEA of these facilities. Figure 1 describes flux concentrator core and two windings coil of the facility fore-and-aft section.

An extensive numerical simulation of the Ignitor-Ult plasma dynamics has been carried out using both the free boundary equilibrium code TEQ and the transport and MHD free boundary code TSC. The stability behavior of the plasma - vacuum vessel - poloidal field coils - passive plate system has been analyzed for different machine and plasma configurations. The response of several feedback systems has been studied taking into account the real characteristics of the power supply. The converter and its controller behavior has been extensively studied by means of the simulation program CSMP that uses a lumped parameter model of the system. The results show a good stability behavior over a wide operating range.

At present, FTU is working with a wide gap between the time constant tp ~ 1 ms of the passive structure and the active time constant ta ~ 25 ms of the whole feedback system. An overview of the last experimental results in the plasma current and position is presented together with the drawbacks connected with the situation. Some system upgradings are under development. Here, we discuss an improvement of the on-line magnetic measurement processing apparatus based on a VME architecture with an OS/9 real-time operating system. This system acquires values of the poloidal flux and the angular components of the magnetic field and, using a mathematical model, calculates and gives the horizontal and vertical position of the plasma, which is the input for the position control system. The system main characteristics are the high speed in data acquisition and processing (< 1 ms), the configurability and the flexibility. The system uses the OS-9 operating system in Ethernet network with the central VAX/VMS. This link has a very high data-transfer velocity due to a special driver. Another useful characteristic of our VME system is the possibility of code development directly from the VAX/VMS to a diskless configuration, using Remote Disk Server and Remote Login functions.