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Summary Current Upstream decarbonization roadmap would require Carbon Capture Storage projects not just to reduce emissions balance, but to achieve negative emissions. First step in this process of “green exploration”, in analogy with convention exploration, will be to screen out favorable basins. Main objective of this “green exploration” is to analyze (feasibility study) which subsurface options could progress on the project management decision process (Carbon Capture & Storage, CCS subsurface). There are evident advantages in mature Oil & Gas basins where producing fields, close to depletion, aligned with dry hole (potential saline aquifer’s) could speed up screening process feasibility. Based on a prior positive screening a project (depleted Oil & Gas Field) could be sanctioned for next milestone: computed 3D Geological Static model, which will integrate all available Geological, Geophysical & Logging data with required interpretation. This paper summarizes main lessons learned gathered from in-house 3D geological modeling of depleted oil & gas fields and saline aquifers (upside green exploration in shallow producing fields horizons). Mentioned 3D Geological Static model has proven to be the corner stone of any further CO2 storage feasibility analysis and a starting point to explore for additional storage resources, outside producing reservoirs.

This paper performs a comprehensive nonlinear modeling of a Bulk Acoustic Wave (BAW) duplexer operating at the band 7 of the LTE wireless communication standard. The modeling starts by an accurate characterization of the resonators forming the filters by performing measurements of the second harmonic (H2). The modeling of individual resonators has then been used to predict second order nonlinear manifestations occurring in a real duplexer. These are H2, second order intermodulation products (IMD2), for the case where a jamming signal is set to low frequencies (IMD2-Low) and when the jamming signal is set to high frequencies (IMD2-High). Predicted results are then validated with real measurements. The authors would like to thank Qorvo Inc. for providing the on-wafer measurements that appear in this article. Work supported in part through grants TEC2017-84817-C2-2-R, TEC2017-88343-C4-2-R and 2017 SGR 813

2018 76th Device Research Conference (DRC) : 24-27 June 2018 / [IEEE Electron Device Society (EDS) - ​technical co-sponsor ; Materials Research Society (MRS) - co-sponsor] 76th Device Research Conference, DRC 2018, Santa Barbara, CA, USA, 24 Jun 2018 - 27 Jun 2018; Piscataway, NJ : IEEE 2 Seiten (2018). doi:10.1109/DRC.2018.8442228, Published by IEEE, Piscataway, NJ

A techno-economic analysis of a natural gas combined cycle (NGCC) integrated with MEA-based CO 2 capture with an advanced configuration is carried out. Sequential supplementary firing in the Heat Recovery Steam Generator (HRSG) is combined with a supercritical combined cycle for the purpose of increasing CO 2 production for Enhanced Oil Recovery (EOR) at a competitive levelised cost of electricity. Supercritical steam conditions with a double reheat in the steam cycle are used to largely improve performance and take full advantage of sequential supplementary firing in the HRSG. Sequential supplementary firing increases the flue gas temperature throughout the Heat Recovery Steam Generator (HRSG) by burning additional fuel at different stages to maximise the use of oxygen available in the flue gas exiting the gas turbine. The positive impact on the post combustion capture plant size and energy requirements for solvent regeneration are attractive for markets with cheap natural gas, and where the emphasis on capital cost reduction is important. This study then investigates the effect of fuel prices and capital costs for this configuration and compares it with a typical combined cycle integrated with MEA-based CO 2 capture. A case study for Mexico is presented, at a range of gas prices where these modifications would be attractive, with a tentative target of $40/tCO 2 .

Linearity of RF filters is in the focus of system-architects as carrier aggregation (CA) schemes in down- and uplink emerge as a requirement. The nonlinear electro-thermal-acoustic constitutive equations of the piezoelectricity and the number of different materials involved in the manufacturing of BAW resonators make it difficult to discern between different sources of nonlinearity. It is hard to identify the root-cause of undesired effects, such as harmonics, intermodulation products and detuning effects. A systematic procedure must be defined to unambiguously determine the origin of nonlinearities, and all the nonlinear observations must be consistent with the stated hypothesis. Better understanding of the nonlinear mechanisms is crucial for designing more linear resonators, and consequently improved filters.

A metamaterial spacer composed of spiral resonators (SRs) and narrow metal strips has been tested to operate like a bidirectional artificial magnetic conductor (AMC) reflector at 2.45 GHz. The performance of the spacer has also been evaluated in a closely spaced multiple-antenna system applied to successfully increase the transmission capacity of a commercial wireless IEEE 802.11b router.

The use of a low profile, light weight and easy to fabricate transpolarising surface placed on one side of a trihedral corner reflector (TCR) as polarimetric calibrator is presented in this letter. The transpolarising-TCR (TTCR) presents a high backscattered cross-polar response contrary to standard TCRs. The performance of this device has been tested at X-band using the UPC GB-SAR., Comment: Accepted for publication in IEEE Geoscience and Remote Sensing Letters

A metamaterial spacer to decorrelate two closely spaced antennas has been designed and tested. The metamaterial spacer exhibits an artificial magnetic conductor (AMC) behavior around 2.6 GHz. Its performance has been checked against a simple metal spacer (PEC), providing a quasi orthogonal radiation pattern and good results in terms of decoupling and decorrelating a two-antenna system. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1414–1417, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23365

Metamaterial slabs made of magnetic resonators (artificial magnetic conductor, AMC surfaces) can provide unusual electromagnetic properties, such as the dual PMC/PEC behavior, when used as reflectors. This property has been assessed and tested with the design and fabrication of a one-layer spiral AMC slab. Moreover, two bidirectional AMC surfaces have also been designed and measured. These structures, composed of spiral (SR) or capacitive loaded loop (CLL) resonators printed on dielectric strips, can provide 0° reflection coefficient phase when the incident electric field wave impinges on any side. A very low electrical thickness is achieved. Compact antenna systems with two (or more) close isolated antennas can be designed with such structures. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1949–1953, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22567

Prefractal Hilbert curves are analyzed in terms of radiation efficiency, quality factor, and electrical size for their use as small self-resonant monopole antennas. The structures show better performance as loads of monopoles than as radiating structures. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 45–49, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11122

The use of a transpolarizing surface placed on one side of a trihedral corner reflector (TCR) as polarimetric calibrator is presented in this paper. The transpolarizing-TCR presents a high back-scattered cross-polar response. This structure has been tested at 9.65 GHz (X-band) with the help of the UPC GB-SAR system.

The primary objective of many antenna measurement facilities is to provide a specified high accuracy of the measured data. The validation of an antenna measurement facility is the process of proving that such a specified accuracy can be achieved. Since this constitutes a very challenging task, antenna measurement accuracy has been the subject of much research over many years and a range of useful measures have been introduced. Facility comparisons, together with antenna standards, error budgets, facility accreditations, and measurement procedure standards, constitute an effective measure towards facility validations. This paper documents the results of a comparison between 8 European antenna measurement facilities with a specially designed reference antenna, the DTU-ESA 12 GHz validation standard antenna (VAST-12). The electrical and mechanical properties of the VAST-12 antenna are presented and its three different coordinate systems are defined. The primary objective of the comparison is to obtain experience and results that can serve to develop standards for validation of antenna measurement facilities. The paper focuses on the comparison of the radiation pattern and presents not only the measurement data obtained at the facilities, but also investigates several procedures for comparing these data. This includes various definitions of pattern difference and statistical measures as well as a reference pattern. The comparison took place in 2004-2005 as part of the European Union network of excellence called ACE-Antenna Centre of Excellence.

Conventional antenna radiation efficiency measurement techniques, such as the Wheeler cap, are generally narrow-band and, thus, well suited for resonant antennas. In this work, the Johnston-Geissler (J-G) method based on the Wheeler cap principle is used in a wide frequency range. First, a good agreement between measurement and simulation in an ultrawide frequency band is shown on a straight wire monopole antenna with different attenuators emulating antenna losses. Then, this technique is used to measure the radiation efficiency of several ultrawideband (UWB) antennas.

The broadside power radiation enhancement has been tested for the case of a magnetic dipole in presence of an MNZ metamaterial substrate. In order to assess the theoretical estimations, a slot antenna on a ground plane has been fabricated and an AMC composed of 1 layer square spiral resonators has been used as an MNZ metamaterial slab. The radiation patterns have been measured in the anechoic chamber, achieving a gain in directivity of more than 1 dB. However, it should be taken into account that the thickness of the fabricated metamaterial slab (6 mm) is much smaller than the theoretical optimum thickness (hundreds of mm). The directivity of the antenna might be improved when increasing the number of layers of the metamaterial slab; in fact, in such a case, the leaky waves responsible of directive radiation are expected to be more significantly excited giving rise to the sought broadside power enhancement.

Transpolarizing surfaces are characterized for their property of rotating by 90deg the reflected electric field with respect to the incident one. Several transpolarizing surface designs are presented, and their potential applications and limitations, mostly for oblique incidence, are discussed.

This paper addresses the need for designing user interfaces (UIs) to workflow information systems by adopting a model-centric approach. We introduce a conceptual workflow model to determine system functionalities of workflow. The model is exploited in order to systematically derive UIs to access these functionalities. The workflow model is recursively decomposed into processes which are in turn decomposed into tasks. Each task gives rise to a task model whose structure, ordering, and connection with the domain model allows the automated generation of their corresponding UIs, using a transformational approach. Each UI is specified in a User Interface Description Language, workflow, process, and task models are specified in the same specification language. The language is exploited to generate multiple source codes, depending on how their corresponding tasks are structured in the process model; and by a workflow execution engine to produce running workflow systems. A real-world case is outlined to exemplify the process.

It is presumed today that spinal cord stimulation induces local delivery of vasoactive substances, such as prostacyclins, histamine, substance P, and vasoactive neuropeptides, in the perivascular envi

Artificial magnetic surfaces have interesting applications in antenna design where one wants to replace, over a limited frequency range, electric conducting surfaces with magnetic equivalents. One of the many challenges in constructing such a surface is that of miniaturizing the resonator elements making up the structure whilst at the same time maintaining a reasonable bandwidth and a tolerable level of dielectric and copper losses. In this paper we present some novel structures, fabricated using chemical etching techniques, which have only 6.5% of the area of a capacitive loaded loop (CLL) and less than 30% of the area of spiral resonators and have measured return losses of less than 1.5 dB.

This paper presents the steady-state and transient stability simulation of a power system with a pulse width modulated (PWM) AC link series compensator (PWMSC). Such device is included into the Newton-Raphson formulation. Results of transient stability simulations are exposed, showing the applicability of the device for such purposes.

Like many multi-dimensional problems, there is not always a single best solution but a set of solutions, known as Pareto front, representing all possible trade-offs that can be made for given problem and criteria. Once the front is identified, the designer can choose the best solution for the current application. In this paper, a particle swarm optimization (PSO) technique is used to determine the Pareto front of a set of possible parabolic resistive loading profiles carried out on a monopole antenna. This Pareto front is the result of an optimization in terms of spatially averaged fidelity (SAP) and mean radiation efficiency for a given bandwidth. The optimum loading profile is selected as a compromise between these two parameters. This Pareto front shows what we could expect from a continuously tapered, resistively loaded monopole for UWB applications.

Artificial Magnetic Conductors (AMCs) offer many reflecting applications. When non symmetrical elements (diagonal slots, offset vias) are used, a cross-polar reflected response is achieved given an incident copolar electric field. This electromagnetic property can be used for polarisation conversion or RCS reduction purposes. A cross-polarising surface composed of square patches and diagonal slots over a ground plane has been designed and measured, providing good results for normal incidence. (4 pages)

An RFID tag based on artificial magnetic conductors is here proposed to work close to metallic planes. The backscattered power is proved to be higher if we use an AMC surface to isolate the tag antenna from the metallic plane, enabling a good detection at the reader even in presence of metals.

A novel transpolarizing or crosspolarizing surface has been proposed to be applied in polarimetric SAR calibrating systems, like trihedrals, since they can not provide initially a crosspolar response. So the trans-surface has been designed and measured in an anechoic chamber, providing good results for normal incidence.

The AMC behavior of a reflecting surface is mainly related to the frequency where the 0deg crossing in the phase of its reflection coefficient takes place. This frequency gives the resonant frequency that characterizes the AMC surface. Two different designs of AMC surfaces showing quite different properties are presented in this communication. A first design proves the AMC behavior using metallic tubes with slotted square profile instead of the typical periodic arrangement of strips printed on a dielectric substrate; and the latter, shows the AMC performance of an artificial material when the electromagnetic waves impinge on its opposite faces.

An artificial magnetic reflector is built based on squared spiral resonators. Numerical simulations using efficient MLMDA (multilevel matrix decomposition algorithm) techniques are used for designing the reflector and the antenna. Measurements of the reflection coefficient of the artificial screen are carried out in order to verify the viability of the proposal. The performance of the reflector in combination with a folded dipole as an active element is also evaluated.

Simulations and measurements have been carried out of a 1-layer metamaterial slab made of spiral resonators that shows an AMC behavior, with an equivalent electrical width of /spl lambda//12 for the thickness (z dimension) of the slab. This behavior has been experimentally verified through radiation pattern measurements. The results show that similar results are obtained by placing a PEC at a /spl lambda//4 distance and by placing the antenna close to the AMC. This latter solution is lower profile.

This paper is aimed to the steady state analysis of a novel unified power flow controller (UPFC). A detailed formulation exhibits its inclusion into a Newton-Raphson's power flow program. Simulation results are presented on a 39-buses power system.

This paper proposes to characterize antennas for UWB applications, considering the transmitter-receiver system, using figures of merit that do not depend on direction. From the basic formulation for a single antenna we extend this concept to a system containing transmit and receive antennas. We use these parameters to optimize dipole design with respect to its conductivity.

A multiobjective genetic algorithm (GA) has been applied to the design of electrically small thin-wire antennas taking into account the resonance frequency, efficiency and Q factor of the different configurations. The performance of the resulting designs is compared to that of other prefractal antennas of similar size.

The fabrication of antennas with recycled materials but with good performance is possible by using the classical formulation from textbooks. Several antenna designs built with materials found at home are shown, and their performance is measured with professional equipment to assess an acceptable agreement between simulations and measurements. Practical design and fabrication of antennas made with used materials and operating at WiFi bands will surely stimulate students of basic topics of antennas to fabricate and test their own designs.

The paper presents the VSWR (voltage standing wave ratio) performance and radiation pattern for a low-profile IFA (inverted-F antenna) matched at 450 MHz. It is known that when the IFA height from a conducting ground plane is approximately one-tenth of the wavelength, the frequency bandwidth for a VSWR=2 criterion is approximately 8%. Nakano et al. (1998) proposed two L-figured parasitic elements added to the IFA to widen the VSWR bandwidth. It should be a large value for handset systems if this criterion is applied to structures working at lower frequencies (450 MHz) such as TETRA. A design of IFA is presented with different lengths for parasitic elements to generate two resonance frequencies near the central frequency of design. Antenna characteristics; mounted on the handset, are calculated using the method of moments (MoM) with wire grid models using numerical electromagnetic code NEC2. The mean effective gain (MEG) for different statistical distribution models of incident waves are presented too.

The paper presents the application of fuzzy control and nonlinear estimation to wastewater treatment plants. This biological process is highly nonlinear and its control is a challenging task due to unmeasured variables and input disturbances. Fuzzy control is quite efficient to reduce the effect of unmeasured disturbances, but the used structure requires the measurement of all the state variables. In order to estimate the unmeasured ones, a nonlinear estimator is proposed. The final control structure is composed by the nonlinear estimator and the fuzzy control. The applicability of the proposed approach is validated via simulations.

We present a positioning system implemented in Java that is designed to provide tourist information for car users. Most of this multimedia information is stored in a local database in the car, but it is possible to increase or update it by accessing a remote database by mobile telephone. The system can be controlled like any standard computer by keyboard or by mouse, but also offers hands-free control based on an oral interface module, which is very important for a system designed to be used inside a car.

The surface current distribution of a Sierpinski fractal antenna shows a self-similar behaviour determined by the self-similar properties of its geometry. The application of infra-red thermography to electromagnetic near field detection allows the experimental verification of the active region scaling of a fractal antenna operating at different bands.

Experimental verification of the fractal Sierpinski antenna surface current distribution is presented. Measured data from an infrared camera agree with numerical data showing a self-similar behavior in the current density distribution over the fractal antenna surface. This result gives a better insight on the multiband behavior of the fractal-shape antenna.

The Universal Fair of Seville, popularly know as EXPO'92, took place from April to October 1992. The land situated on the "Isla de la Cartuja" was built on and inhabited for this event, and two HV/MV substations were built to supply the MV/LV centres via a 20 kV underground network. These centres supplied electricity to the pavilions that were erected, and the installations of associated services. Once the Fair was over and some of the participating countries' pavilions taken down, several of the MV/LV substations were dismounted leaving the network in that area with the same configuration as today. In this study we establish comparisons between this newer, simply designed and remote controlled network, and the network in the city of Seville which has elements of different ages and the typical complexity of networks that have been built in stages.

The main objective of the SLACE system (automatic reading of electricity meters) is to obtain automatic readings from customer's watthour meters, but it also offers other additional uses. The system comprises a series of different units which are all interconnected in different ways. Its characteristics and functions are described in this paper. (6 pages)

summary Previous studies support the view that the oral medium is a dynamic system composed of several elements, among which are restorations in teeth. The author believes that the evolution in time of a restoration can be non-lineal and that it has an irregular and chaotic behaviour. To investigate the theory, the author studied, between 1991 and 1994, on their first visit to a dental clinic in Salamanca, the restorations of 583 patients of both sexes. The group results were distributed throughout three age ranges, i.e. 16-65, 26-55 and 36-45. In each group the total number of fillings in situ in each tooth was recorded using the method ‘Expansion-Contraction Systems’. The results show that the restorative treatment of teeth using fillings follows a non-lineal dynamic of chaotic behaviour and irregular geometry, which suggests it is a fractal.

Background The advantages of orally active chemotherapy make it a valuable option for treating cancer patients. Purpose To assess the use and cost of oral vinorelbine (OV) in a regional hospital. Materials and methods A retrospective descriptive study carried out from January 2009 till September 2010. The authors report on all the patients who were treated with OV during the period of study. The authors checked the following information: sex, age, diagnosis, previous and subsequent chemotherapy regimens, chemotherapy regimen, mean dose, patient-related cost and overall cost. Results The authors studied 21 patients (80.9% men and 19.1% women) with a mean age of 68.1±8.9 years. 15 patients were diagnosed with non-small cell lung cancer (NSCLC), 3 with breast cancer (BC) and 3 with prostate cancer (PC). 40% of patients with NSCLC had previously been treated with cisplatin-paclitaxel or cisplatin-gemcitabine whereas 60% had been treated with cisplatin-vinorelbine or vinorelbine alone. With regard to the other diagnoses: 3 patients with BC had been treated with paclitaxel-anthracycline and 3 patients with PC had been treated with paclitaxel-carboplatin. For the current treatment, the distribution of treatments was the following: a) OV monotherapy (6), b) OV associated with cisplatin (6), c) docetaxel monotherapy (2) and c) without treatment (7). The chemotherapy regimens with OV were: 60 mg/m2, on the 1st and 8th day every 21 days (71.4%); 60 mg/m2, on the 1st and 8th day every 21 days the first cycle and 80 mg/m2, on the 1st and 8th day every 21 days in the following cycles (14.3%); 60 mg/m2, on days 1, 8 and 15 every 28 days (14.3%). Average dose of OV was 110.4±13.6 mg with an average number of prescriptions dispensed of 4.7±2.7. Only 9 patients had received prior intravenous vinorelbine. Patient-related cost was 1,314.08 € and overall cost was 14,454.96 €. Conclusions In our hospital, OV was used in accordance with the guidelines except that the absence of intravenous vinorelbine first in 42.8% of patients should be justified. Although the cost of OV is high it is justifiable because it avoids indirect costs.