Developing alternative shoreline armoring strategies: the living shoreline approach in North Carolina

This paper reviews the scientific data on the ecosystem services provided by shoreline habitats, the evidence for adverse impacts from bulkheading on those habitats and services, and describes alternative approaches to shoreline stabilization, which minimize adverse impacts to the shoreline ecosystem. Alternative shoreline stabilization structures that incorporate natural habitats, also known as living shorelines, have been popularized by environmental groups and state regulatory agencies in the mid-Atlantic. Recent data on living shoreline projects in North Carolina that include a stone sill demonstrate that the sills increase sedimentation rates, that after 3 years marshes behind the sills have slightly reduced biomass, and that the living shoreline projects exhibit similar rates of fishery utilization as nearby natural fringing marshes. Although the current emphasis on shoreline armoring in Puget Sound is on steeper, higher-energy shorelines, armoring of lower-energy shorelines may become an issue in the future with expansion of residential development and projected rates of sea level rise. The implementation of regulatory policy on estuarine shoreline stabilization in North Carolina and elsewhere is presented. The regulatory and public education issues experienced in North Carolina, which have made changes in estuarine shoreline stabilization policy difficult, may inform efforts to adopt a sustainable shoreline armoring strategy in Puget Sound. A necessary foundation for regulatory change in shoreline armoring policy, and public support for that change, is rigorous scientific assessment of the variety of services that natural shoreline habitats provide both to the ecosystem and to coastal communities, and evidence demonstrating that shoreline armoring can adversely impact the provision of those services.

A comparison of methods for the coupled analysis of floating structures

The dynamic analysis of a deepwater floating platform and the associated mooring/riser system should ideally be fully coupled to ensure a reliable response prediction. It is generally held that a time domain analysis is the only means of capturing the various coupling and nonlinear effects accurately. However, in recent work it has been found that for an ultra-deepwater floating system (2000m water depth), the highly efficient frequency domain approach can provide highly accurate response predictions. One reason for this is the accuracy of the drag linearization procedure over both first and second order motions, another reason is the minimal geometric nonlinearity displayed by the mooring lines in deepwater. In this paper, the aim is to develop an efficient analysis method for intermediate water depths, where both mooring/vessel coupling and geometric nonlinearity are of importance. It is found that the standard frequency domain approach is not so accurate for this case and two alternative methods are investigated. In the first, an enhanced frequency domain approach is adopted, in which line nonlinearities are linearized in a systematic way. In the second, a hybrid approach is adopted in which the low frequency motion is solved in the time domain while the high frequency motion is solved in the frequency domain; the two analyses are coupled by the fact that (i) the low frequency motion affects the mooring line geometry for the high frequency motion, and (ii) the high frequency motion affects the drag forces which damp the low frequency motion. The accuracy and efficiency of each of the methods are systematically compared. Copyright © 2007 by ASME.

Nonsmooth geometry and collapse of flexible structures under smooth loads

While static equilibria of flexible strings subject to various load types (gravity, hydrostatic pressure, Newtonian wind) is well understood textbook material, the combinations of the very same loads can give rise to complex spatial behaviour at the core of which is the unilateral material constraint prohibiting compressive loads. While the effects of such constraints have been explored in optimisation problems involving straight cables, the geometric complexity of physical configurations has not yet been addressed. Here we show that flexible strings subject to combined smooth loads may not have smooth solutions in certain ranges of the load ratios. This non-smooth phenomenon is closely related to the collapse geometry of inflated tents. After proving the nonexistence of smooth solutions for a broad family of loadings we identify two alternative, critical geometries immediately preceding the collapse. We verify these analytical results by dynamical simulation of flexible chains as well as with simple table-top experiments with an inflated membrane.

Electroluminescence from Au/(SiO2/Si/SiO2) nanometer double barrier/p-Si structures and its mechanism

SiO2/Si/SiO2 nanometer double barriers (SSSNDB) with Si layers of twenty-seven different thicknesses in a range of 1-5 nm with an interval of 0.2 nm have been deposited on p-Si substrates using two-target alternative magnetron sputtering. Electroluminescence (EL) from the semitransparent Au film/SSSNDB/p-Si diodes and from a control diode without any Si layer have been observed under forward bias. Each EL spectrum of all these diodes can be fitted by two Gaussian bands with peak energies of 1.82 and 2.25 eV, and full widths at half maximum of 0.38 and 0.69 eV, respectively. It is found that the current, EL peak wavelength and intensities of the two Gaussian bands of the Au/SSSNDB/p-Si structure oscillate synchronously with increasing Si layer thickness with a period corresponding to half a de Broglie wavelength of the carriers. The experimental results strongly indicate that the EL originates mainly from two types of luminescence centres with energies of 1.82 and 2.25 eV in the SiO2 barriers, rather than from the nanometer Si well in the SSSNDB. The EL mechanism is discussed in detail.

I wanna be a protocol: online media and electronic structures of kinship

Heidegger famously identified Modernity with a technological leveling of being to a single order of a “standing reserve.” In a radically different tone, Gilles Deleuze articulated a single “plane of immanence” within which ontological distinctions between mind and body, God and world, interiority and exteriority become indiscernible. Taking such philosophical declarations as points of departure, this panel will consider how a collapse of ontological distinction emerged as a thematic and structural trope in literary and cinematic modernisms. We hope to consider how writers and film-makers of the 20th c. utilize the resources of their media to ask “the question of being” that troubled their philosophical contemporaries and heirs. In this vein, we will examine how these modernist ontologies of immanence describe the crisis of a subject saturated and eclipsed by a world which comprises her while also remaining strange or opaque. Papers will ask what is lost with the departure of a distinctly human sense of “being” and how the historical arrival of an alternative ontological order may be evident in the lived experience of modernity. In this sense, the relationship to departures and arrivals becomes the modern subject’s suspicion that he is unable to do either vis á vis the world.

The social consequences of broken urban structures: a case study of Belfast

This article explores how the design and layout of the urban environment can have significant social impacts on working class communities whose access to employment and other necessary services depends largely on public transport and safe walk-able streets. It does so by considering a case study of Belfast. Although Belfast has a distinctive recent history as the site of political violence and territorial division, it also has a spatial configuration that emerged out of a modernising roads and redevelopment programme in the 1960s and 1970s. However, an understanding of contemporary Belfast, particularly its urban structure and form, requires n analysis of how the social impacts of such ubiquitous regional and urban planning practices were not addressed. The article argues that a culture of ‘politically safe’ bureaucratic inaction developed during the ‘war years’ has been sustained in the ‘new democracy’. In turn, this has had significant consequences for the functioning of the city. Major areas of derelict land around the city core together with the impediments created by regional road infrastructure have combined to create a doughnut city that, on the one hand, facilitates a commuting middle class, while on the other, discriminates against the poorest inner city communities. The article goes on to examine how an activist urban design group, known as the Forum for Alternative Belfast, has responded to these challenges. It focuses particularly on action-research undertaken during its 2010 Summer School which aimed to address issues of disconnection in inner North Belfast that affect some of the most territorialised and deprived communities in the city.

New and Alternative Social Movements in Spain: The Left, Identity and Globalizing Processes

This collection offers a diachronic analytical study of new and alternative social movements in Spain from the democratic transition to the first decade of the 21st century, paying attention to anti-war mobilizations and the use of new technologies as a mobilizing resource. New and alternative social movements are studied through the prism of identified linkages among the left, movement identities and global processes in the Spanish context. Weight is given to certain important historical aspects, like Spain’s relatively recent authoritarian past, and certain value-added factors, such as the weak associationalism and materialism exhibited by the Spanish public. These are complemented by exploring insights offered by key theoretical approaches on social movements (political opportunities structures, resource mobilization). The volume covers established social movement cases (gender, peace, environmental movements) as well as those with a more explicit connection to the current context of global contestation (squatters’ and anti-globalization movements).

The use of an instrumented vehicle in a wavelet based damage detection approach for bridge structures

Periodic monitoring of structures such as bridges is necessary as their condition can deteriorate due to environmental conditions and ageing, causing the bridge to become unsafe. This monitoring - so called Structural Health Monitoring (SHM) - can give an early warning if a bridge becomes unsafe. This paper investigates an alternative wavelet-based approach for the monitoring of bridge structures which consists of the use of a vehicle fitted with accelerometers on its axles. A simplified vehicle-bridge interaction model is used in theoretical simulations to examine the effectiveness of the approach in detecting damage in the bridge. The accelerations of the vehicle are processed using a continuous wavelet transform, allowing a time-frequency analysis to be performed. This enables the identification of both the existence and location of damage from the vehicle response. Based on this analysis, a damage index is established. A parametric study is carried out to investigate the effect of parameters such as the bridge span length, vehicle speed, vehicle mass, damage level, signal noise level and road surface roughness on the accuracy of results. In addition, a laboratory experiment is carried out to validate the results of the theoretical analysis and assess the ability of the approach to detect changes in the bridge response.

FRP reinforcement of timber structures

Timber engineering has advanced over recent decades to offer an alternative to traditional materials and methods. The bonding of fibre reinforced plastics (FRP) with adhesives to timber structures for repair and strengthening has many advantages. However, the lack of established design rules has strongly restrained the use of FRP strengthening in many situations, where these could be a preferable option to most traditional techniques. A significant body of research has been carried out in recent years on the performance of FRP reinforced timber and engineered wood products. This paper gives a State of the Art summary of material formulations, application areas, design approaches and quality control issues for practical engineers to introduce on-site bonding of FRP to timber as a new way in design for structural repair and rehabilitation.

Ferroelectric : CNTs structures fabrication for advanced functional nano devices

This work is about the combination of functional ferroelectric oxides with Multiwall Carbon Nanotubes for microelectronic applications, as for example potential 3 Dimensional (3D) Non Volatile Ferroelectric Random Access Memories (NVFeRAM). Miniaturized electronics are ubiquitous now. The drive to downsize electronics has been spurred by needs of more performance into smaller packages at lower costs. But the trend of electronics miniaturization challenges board assembly materials, processes, and reliability. Semiconductor device and integrated circuit technology, coupled with its associated electronic packaging, forms the backbone of high-performance miniaturized electronic systems. However, as size decreases and functionalization increases in the modern electronics further size reduction is getting difficult; below a size limit the signal reliability and device performance deteriorate. Hence miniaturization of siliconbased electronics has limitations. On this background the Road Map for Semiconductor Industry (ITRS) suggests since 2011 alternative technologies, designated as More than Moore; being one of them based on carbon (carbon nanotubes (CNTs) and graphene) [1]. CNTs with their unique performance and three dimensionality at the nano-scale have been regarded as promising elements for miniaturized electronics [2]. CNTs are tubular in geometry and possess a unique set of properties, including ballistic electron transportation and a huge current caring capacity, which make them of great interest for future microelectronics [2]. Indeed CNTs might have a key role in the miniaturization of Non Volatile Ferroelectric Random Access Memories (NVFeRAM). Moving from a traditional two dimensional (2D) design (as is the case of thin films) to a 3D structure (based on a tridimensional arrangement of unidimensional structures) will result in the high reliability and sensing of the signals due to the large contribution from the bottom electrode. One way to achieve this 3D design is by using CNTs. Ferroelectrics (FE) are spontaneously polarized and can have high dielectric constants and interesting pyroelectric, piezoelectric, and electrooptic properties, being a key application of FE electronic memories. However, combining CNTs with FE functional oxides is challenging. It starts with materials compatibility, since crystallization temperature of FE and oxidation temperature of CNTs may overlap. In this case low temperature processing of FE is fundamental. Within this context in this work a systematic study on the fabrication of CNTs - FE structures using low cost low temperature methods was carried out. The FE under study are comprised of lead zirconate titanate (Pb1-xZrxTiO3, PZT), barium titanate (BaTiO3, BT) and bismuth ferrite (BiFeO3, BFO). The various aspects related to the fabrication, such as effect on thermal stability of MWCNTs, FE phase formation in presence of MWCNTs and interfaces between the CNTs/FE are addressed in this work. The ferroelectric response locally measured by Piezoresponse Force Microscopy (PFM) clearly evidenced that even at low processing temperatures FE on CNTs retain its ferroelectric nature. The work started by verifying the thermal decomposition behavior under different conditions of the multiwall CNTs (MWCNTs) used in this work. It was verified that purified MWCNTs are stable up to 420 ºC in air, as no weight loss occurs under non isothermal conditions, but morphology changes were observed for isothermal conditions at 400 ºC by Raman spectroscopy and Transmission Electron Microscopy (TEM). In oxygen-rich atmosphere MWCNTs started to oxidized at 200 ºC. However in argon-rich one and under a high heating rate MWCNTs remain stable up to 1300 ºC with a minimum sublimation. The activation energy for the decomposition of MWCNTs in air was calculated to lie between 80 and 108 kJ/mol. These results are relevant for the fabrication of MWCNTs – FE structures. Indeed we demonstrate that PZT can be deposited by sol gel at low temperatures on MWCNTs. And particularly interesting we prove that MWCNTs decrease the temperature and time for formation of PZT by ~100 ºC commensurate with a decrease in activation energy from 68±15 kJ/mol to 27±2 kJ/mol. As a consequence, monophasic PZT was obtained at 575 ºC for MWCNTs - PZT whereas for pure PZT traces of pyrochlore were still present at 650 ºC, where PZT phase formed due to homogeneous nucleation. The piezoelectric nature of MWCNTs - PZT synthesised at 500 ºC for 1 h was proved by PFM. In the continuation of this work we developed a low cost methodology of coating MWCNTs using a hybrid sol-gel / hydrothermal method. In this case the FE used as a proof of concept was BT. BT is a well-known lead free perovskite used in many microelectronic applications. However, synthesis by solid state reaction is typically performed around 1100 to 1300 ºC what jeopardizes the combination with MWCNTs. We also illustrate the ineffectiveness of conventional hydrothermal synthesis in this process due the formation of carbonates, namely BaCO3. The grown MWCNTs - BT structures are ferroelectric and exhibit an electromechanical response (15 pm/V). These results have broad implications since this strategy can also be extended to other compounds of materials with high crystallization temperatures. In addition the coverage of MWCNTs with FE can be optimized, in this case with non covalent functionalization of the tubes, namely with sodium dodecyl sulfate (SDS). MWCNTs were used as templates to grow, in this case single phase multiferroic BFO nanorods. This work shows that the use of nitric solvent results in severe damages of the MWCNTs layers that results in the early oxidation of the tubes during the annealing treatment. It was also observed that the use of nitric solvent results in the partial filling of MWCNTs with BFO due to the low surface tension (<119 mN/m) of the nitric solution. The opening of the caps and filling of the tubes occurs simultaneously during the refluxing step. Furthermore we verified that MWCNTs have a critical role in the fabrication of monophasic BFO; i.e. the oxidation of CNTs during the annealing process causes an oxygen deficient atmosphere that restrains the formation of Bi2O3 and monophasic BFO can be obtained. The morphology of the obtained BFO nano structures indicates that MWCNTs act as template to grow 1D structure of BFO. Magnetic measurements on these BFO nanostructures revealed a week ferromagnetic hysteresis loop with a coercive field of 956 Oe at 5 K. We also exploited the possible use of vertically-aligned multiwall carbon nanotubes (VA-MWCNTs) as bottom electrodes for microelectronics, for example for memory applications. As a proof of concept BiFeO3 (BFO) films were in-situ deposited on the surface of VA-MWCNTs by RF (Radio Frequency) magnetron sputtering. For in situ deposition temperature of 400 ºC and deposition time up to 2 h, BFO films cover the VA-MWCNTs and no damage occurs either in the film or MWCNTs. In spite of the macroscopic lossy polarization behaviour, the ferroelectric nature, domain structure and switching of these conformal BFO films was verified by PFM. A week ferromagnetic ordering loop was proved for BFO films on VA-MWCNTs having a coercive field of 700 Oe. Our systematic work is a significant step forward in the development of 3D memory cells; it clearly demonstrates that CNTs can be combined with FE oxides and can be used, for example, as the next 3D generation of FERAMs, not excluding however other different applications in microelectronics.

Non-linear analysis of composite structures with integrated piezoelectric sensors and actuators

This paper deals with the geometrically non linear analysis of thin plate/shell laminated structures with embedded integrated piezoelectric actuors or sensors layers and/or patches.The model is based on the Kirchhoff classical laminated theory and can be applied to plate and shell adaptive structures with arbitrary shape, general mechanical and electrical loadings. the finite element model is a nonconforming single layer triangular plate/shell element with 18 degrees of fredom for the generalized displacements and one eçlectrical potential degree of freedom for each piezoelectric layer or patch. An updated Lagrangian formulation associated to Newton-Raphson technique is used to solve incrementally and iteratively the equilibrium equation.The model is applied in the solution of four illustrative cases, and the results are compared and discussedwith alternative solutions when available.

Grant of Permission for lease of military lands from Sir Robert Prescott to Thomas Clark, 1798-1801.

Transcript (original spelling and grammar retained): By His Excellency Robert Prescott Esquire, Captain General and Governor in Chief in and over His Majestys Provinces of Upper and Lower Canada, General and Commander in Chief of all His Majesty’s forces in the Provinces of Upper and Lower Canada, Nova Scotia, New Brunswick and their several Dependencies and in the Island of Newfoundland &ca. &ca. &ca. I do hereby authorise and permit Thomas Clark of Queenstown in the County of Lincoln in the Province of Upper Canada merchant to take possession of all that Lot, piece and parcel of Land (being part of the land reserved by his Majesty for Military purposes) situate, lying and being at Queenstown in the Township of Newark, in the Home District in the said Province of Upper Canada, bounded and abutted as follows, that is to say beginning at the Distance of two Chains and ninety links from the South East End of his Majesty’s Store House, the said distance being measured along the Bank up Stream, thence South thirty nine degrees and an half West one Chain and fifty links thence south fifty degrees and an half East one Chain and thirty links thence North thirty nine degrees and an half East to the Edge of the Bank and from thence along the Bank to the place of beginning, containing thirty one perches and one hundred and twenty five square links and to occupy and hold the said Lot, piece and parcel of Land during pleasure subject nevertheless to the provisoes and Conditions herein after contained, that is to say. First on condition that it shall and may be lawful to and for His Majesty his Heirs and Successors and to and for the Commander in Chief of His Majesty Forces for the time being and to and for the Officer commanding his Majesty’s Forces in Upper Canada for the time being and to and for either of them to determine and make void this present permission to occupy during pleasure the said Lot, Piece or Parcel of Land above described at any time hereafter whenever he or they shall see fit so to do without any compensation or indemnification to the said Thomas Clark or any other Person or Persons whosoever for any Loss Injury or Damage which he the said Thomas Clark or any other Person or Persons whosoever may thereby sustain. Secondly on this further Condition that it shall and may be lawful to and for His Majesty his Heirs and Successors and to and for his and their Officers, Soldiers and Servants at any time hereafter by order of the Commander in Chief of His Majesty’s Forces for the time being or by order of the Officer commanding his Majesty’s forces in Upper Canada for the time being or by order of the Officer of His Majesty’s Corps of Royal Engineers commanding in the said Province of Upper Canada for the time being to enter upon the said Lot Piece and parcel of Land which the said Thomas Clark is hereby permitted to occupy during pleasure or upon any part thereof and to take down and from the said Lot piece and parcel of Land or from any part thereof to remove any dwelling House Store or other Buildings on the said Lot, piece or Parcel of Land or any part thereof erected and to remove any goods or Chattels on the said Lot piece and parcel of Land or on any part thereof or on any such dwelling House Store or other building found or being and that His Majesty his Heirs and Successors or any other Person or Persons whosoever shall not be liable or responsible to the said Thomas Clark or to any other Person or Persons whosoever for any Loss, Injury or Damage which he or they shall or may in such case sustain. Thirdly on this further Condition that the said Thomas Clark shall not erect on the said Lot Piece or Parcel of Land which the said Thomas Clark is hereby permitted to occupy during pleasure or upon any part thereof at any time or times hereafter any dwelling House store or other Building whatsoever of Stone or brick or of any other materials wood only exccepted and that if any dwelling House or Store or other building of Stone or brick or of any other materials except wood shall at any time be erected on the said Lot, piece or parcel of Land or upon any part thereof, then and in such case, this present permission and every Clause and Article thereof shall from thenceforth cease and determine and be absolutely and entirely null and void. And lastly on this further Condition that the said Thomas Clark or any other Person whosoever shall not assign this permission to occupy the said Lot, Piece or Parcel of Land above described to any Person of Persons whosoever, and if any such assignment shall be made by the said Thomas Clark or by any other Person in his right, or on his behalf, that then and in such case such assignment and this permission to occupy during pleasure the said Lot piece and parcel of Land above described, and every Clause and Article thereof shall from thenceforth cease and determine and be absolutely and entirely null and void. Given under my hand at the Castle of St. Lewis in the City of Quebec in the Province of Lower Canada this Ninth day of July in the year of our Lord one thousand seven hundred and ninety eight and in the thirty eighth year of His Majesty’s Reign. [Signed here by Robert Prescott] By Order of the Commander in Chief [Signed here by James Green (Illegible signature)] I the said Thomas Clark above named do hereby accept the above written Permission to occupy during pleasure the said Lot piece and parcel of Land above described upon and subject to the several Provisioes and Conditions above written and each and every of them severally and respectively. In witness whereof I have hereunto set my hand the Sixteenth day of August in the year of our Lord one thousand seven hundred and ninety eight and in the thirty eighth year of His Majesty’s Reign. [Signed here by Thomas Clark] Signed in the presence of [Illegible signature – looks like J. M Donell Lt. Col.] [Illegible – looks like 2d. Battn R. C. Sm?] [Signed here by C. Anderson] Whereas Inconveniences did arise from the peculiar situation of the Ground contiguous to the above described Lot of Land and the occupation thereof, if estimated by the above Limits would prove highly disadvantageous to Mr. Thomas Clark be it known that in consideration thereof we do permit the above Lot to extend one half Chain more in length up stream so as to comprehend the space allowed for the Road between Lots Two + Three, and we do hereby appropriate the said additional space wholly to the use of the said Thomas Clark. In witness whereof we have hereunto subscribed this Thirteenth Day of October in the Year of our Lord one thousand Eight Hundred and one. [Signed here by J. M’Donell Lt. Col] 2d. Battn. R. C. [in?] Com of Fort George + Dependencies Robt. Pilkington Captain Royal Engineers

La souveraineté alimentaire dans le système-monde : une étude comparative des structures agraires cubaine et mexicaine

Suite à l‘éclatement de la bulle des « subprimes » en 2008, le tournant décisif de cette période de crise, toutes les attentions se sont focalisées sur la crise de la « finance mondialisée », masquant d‘autres conséquences de la crise aussi lourdes et perverses que l‘essor du chômage et le resserrement du crédit (Carfantan 2009). Ce travail se consacre ainsi aux autres aspects de la crise tels que vécus à la campagne, en particulier la crise alimentaire et la crise des sociétés paysannes. Le point central de cette recherche porte plus particulièrement sur la montée de « l‘alternative de la souveraineté alimentaire » en réponse à la crise agraire de manière à poser un véritable défi au modèle agroalimentaire du néolibéralisme (Desmarais 2008; Holt-Giménez 2009). La présente recherche étudie donc les déterminants sociopolitiques qui conduisent à l‘édification des politiques de souveraineté alimentaire malgré la pression du régime alimentaire néolibéral. Ce mémoire avance que les politiques de souveraineté alimentaire sont issues de contre-mouvements paysans qui parviennent, en premier lieu, à établir une structure domestique agraire de nature « populaire-démocratique » et « antisystémique », et en second lieu, à transnationaliser cette structure de manière à défier le régime alimentaire néolibéral en crise. En adaptant la théorie intermédiaire de « structures domestiques » à l‘étude critique des structures agraires autour de trois différentes variables (Risse-Kappen 1999), le mémoire soutient que l‘émergence des politiques de souveraineté alimentaire nécessite la décentralisation de la prise de décision et la collectivisation du secteur agricole à travers une transformation agraire radicale et agroécologique (variable de « structure politique »), de même que l‘émergence d‘une structure sociétale agraire robuste construite sur des réseaux politiques consensuels, en présence d‘un État puissant et d‘une société civile agraire mobilisée (variables de « structure sociétale » et de « réseaux politiques »). Au niveau conceptuel, la recherche repose sur la théorie du système-monde, et consiste en une étude comparative modelée sur une étude de cas contrastes; le cas de Cuba, caractérisé par une forte résistance aux défis agroalimentaires du système-monde contemporain, et celui du Mexique, marqué par l‘adoption des politiques alimentaires néolibérales.

Comparison of Electromagnetic Band Gap and Split-Ring Resonator Microstrip Lines as Stop Band Structures

In this paper, microstrip lines magnetically coupled to splitring resonators (SRRs) are conquved to electromagnetic bundgup (EBG) nr,rrostrip lines in terns q/ their stop-heard penjbrnmrnce and dimensions. In bath types o/ trunsmis•siou lines, signal propagation is inhibited in it certain jequency bwuL For EBG microstrip lines, the central frequency of such a forbidden band is determined by the period of the structure, whereas in SRR-hased microstrip lines the position of the frequency gap depends on the quasi-static resonant frequency of the rings. The main relevant conrributiun of this paper is to provide a tuning procedure to control the gap width in SRR microstrip lines, and to show that by using SRRs, device dimensions ale much smaller than those required by EBGs in order to obtain similar stop-banal performance. This has been demonstrated by fill-wave electromagnetic simulations and experimentally verified from the characterization ql two fabricated microstrip lines: one with rectangular SRRs etched on the upper substrate side, and the other with a periodic perturbation cf'strip width. For similar rejection and 1-(;H,. gap width centered at 4.5 Gllz, it has been found that the SRR microstrip line is•,fve times shorter. In addition, no ripple is appreciable in the allowed band for the .SRR-hared structure, whereas due to dispersion, certain mismatch is expected in the EBG prototype. Due to the high-frequency selectivity, controllable gap width, and small dimensions, it is believed that SRR coupled to planar transmission lines can have an actual impact on the design of stop-band filters compatible with planar technology, and can be an alternative to present solutions based on distributed approaches or EBG

The challenge of self-regulation in commercial property leasing: a study of lease codes in the UK.

Purpose – UK Government policy to address perceived market failure in commercial property leasing has largely been pursued through industry self-regulation. Yet, it is proving difficult to assess whether self-regulation on leasing has been a “success”, or even to determine how to evaluate this. The purpose of this paper is to provide a framework for this and a clearer understanding of self-regulation in commercial leasing. Design/methodology/approach – A literature review suggests key criteria to explain the (in)effectiveness of self-regulation. UK lease codes are analysed in the light of this literature, drawing on previous research carried out by the authors on the operation of these codes. Findings – Lease codes appear to be failing as an effective system of self-regulation. While there are influential market actors championing them, the fragmentation of the leasing process lessens this influence. The structures are not there to ensure implementation, monitor compliance and record views of affected stakeholders. Research limitations/implications – This work adds to the literature on self-regulation in general, and provides an insight into its operation in a previously unexplored industry. Research is needed into the experience of other countries in regulating the property industry by voluntary means. Social implications – There are institutional limitations to self-regulation within the property industry. This has implications for policy makers in considering the advantages and limitation of using a voluntary solution to achieve policy aims within the commercial leasing market. Originality/value – This paper provides a first step in considering the lease codes in the wider context of industry self-regulation and is relevant to policy makers and industry bodies.