bluuebunny/crossref_metadata_2025 huggingface dataset:
Pakk Ya Cah in Havid Yard: Seeing Historic Boston on Foot
Authors: Schlozman Daniel
Published: September 2013

The home of America's first university, its first public school, and its first public library, the Boston area now hosts more than two hundred thousand students. From 1630, when John Winthrop said Boston should be “a city on a hill,” through the McGuffey readers of the nineteenth century, the city has been a beacon of learning. Its politics have been long and colorful: Massachusetts boasts the oldest continuously used, written Constitution in the world, John Adams's 1780 state constitution; the gerrymander was named after Governor Elbridge Gerry's plan for redrawing North Shore districts; the early years of this century saw fierce Yankee-Irish battles for the State House. Massachusetts produced and remains transfixed by the Kennedys, was the only state to vote for George McGovern, and has another interesting gubernatorial race this year. (Keep an eye peeled for people standing with election signs at busy intersections, a local political tradition.) In short, Boston holds much allure for the political scientist.

For the tourist, too, Boston is an appealing destination. It is a compact city and, in the words of the old travel cliché, a city best appreciated on foot (or by public transportation). Most sites of interest in the historic downtown and nearby nineteenth-century neighborhoods are within walking distance of each other. There are restaurants, shops, book-stores, and a certain European vitality of city life—perhaps the result of narrow streets and ample green space. For walkers, the Freedom Trail organizes most of the major Revolution-era sites, and plenty of other spots are marked in the historic core. The same history, though, means Boston's streets were laid out on seventeenth-century cowpaths.
“The Man of Iron” and Men of Power in Poland
Authors: Przeworski Adam
Published: September 2013

Ostensibly, “The Man of Iron” is a film about a successful strike, the culmination of ten years of hope and struggle, an act of solidarity among workers who have understood that the only guarantee of their material well-being and their freedom is the union, an autonomous power of their own. It is a film about a strike and, midway, director Andrzej Wajda turns it into a classical flick, a banal love story seen so many times before, with scenes of a train station, wrapped in blue mist, where a mother takes her child, wrapped in red blankets, away from the intruding repression. One enters the climate of Gorky'sMother, of “Adelein 31,” of “Norma Jean.”

Several Polish and French reviewers did not like this sentimental injection of private life, accusing the film of formal inconsistency, but I find the formalism of the strike film as profoundly ironic as the event itself: the strike of workers against the society where the working class was supposed to hold power, the strike against a party which claimed to represent them turned out to be just a strike like other strikes of workers against the power of capital and the state.

And the ending–one of the endings–is equally romantic: the hero and his woman reunited after she is freed from prison by the victory of strikers, the protagonist in the closing monologue turning to the generation of his father to report the accomplishment of the task.
Priming Moral Self-Ambivalence Heightens Deliberative Behaviour in Self-Ambivalent Individuals
Authors: Perera-Delcourt Ramesh , Nash Robert A. , Thorpe Susan J.
Published: September 2013

Background: Recent work on cognitive-behavioural models of obsessive-compulsive disorder has focused on the roles played by various aspects of self-perception. In particular, moral self-ambivalence has been found to be associated with obsessive-compulsive phenomena. Aims: In this study we used an experimental task to investigate whether artificially priming moral self-ambivalence would increase participants’ deliberation on ethical problems, an index that might be analogous to obsessive-compulsive behaviour. Method: Non-clinical participants completed two online tasks designed to prime either moral self-ambivalence, general uncertainty, or neither. All participants then completed a task requiring them to consider solutions to moral dilemmas. We recorded the time participants took to respond to the dilemmas and the length of their responses; we then combined these variables to create a measure of deliberation. Results: Priming moral self-ambivalence led to increases in deliberation, but this was only significant among those participants who scored highly on a baseline measure of moral self-ambivalence. Priming general uncertainty had no significant effect upon deliberation. Conclusions: The results suggest that moral self-ambivalence may play a role in the maintenance of obsessive-compulsive behaviour. We propose that individuals who are morally self-ambivalent might respond to situations in which this ambivalence is made salient by exhibiting behaviour with obsessive-compulsive characteristics. These findings have implications for the incorporation of ideas about self-concept into theories of obsessive-compulsive disorder.
Scriptural Reasoning and the Anglican–Muslim Encounter
Authors: Ahmed Rumee
Published: September 2013

The process of scriptural reasoning promises to facilitate dialogue and understanding across religious divides. In this paper, the author reflects on the experience of scriptural reasoning with Anglicans and Muslims; describing the phenomenon of ‘fellowship, not consensus’ with reference to key points of doctrinal difference between the two religious traditions.
Scripture, Conversation and Anglican Identity
Authors: McGowan Andrew
Published: September 2013

This editorial piece considers the implications of Scriptural Reasoning, a method of inter-religious exchange that is the subject of the present number of the journal, for contemporary Anglicanism. It suggests that the character of Scriptural Reasoning as a conversation held across and despite religious difference offers a challenge to contemporary Anglicans to maintain their own conversation about Scripture.
The taxonomic status of the phytosaurs (Archosauriformes) Machaeroprosopus and Pseudopalatus from the Late Triassic of the western United States
Authors: Parker William G. , Hungerbühler Axel , Martz Jeffrey W.
Published: September 2013

The genus Machaeroprosopus has long been considered invalid because the type specimen of the Late Triassic phytosaur species, M. validus, has been lost. Re-examination of the primary literature regarding the establishment of the Late Triassic phytosaur genus Machaeroprosopus demonstrates that M. buceros is the correct type species, not M. validus. Thus, the genus level name Machaeroprosopus has priority over the genera Pseudopalatus and Arribasuchus and all nominal species should be reassigned. Reassignment of these species to Machaeroprosopus satisfies the requirements of the International Code of Zoological Nomenclature (ICZN) and preserves historical context. The name Pseudopalatinae is retained as the valid clade name for these phytosaurs because its usage falls outside of the ICZN.
Ultrasonic imaging contrast enhancement using modified dehaze image model
Authors: Guo Dequan , Liu Paul , She Yue , Yang Hongyu , Liu Dong
Published: September 2013

In practical ultrasonic images, post‐processing that involves incoherent frame averaging such as persistence, spatial compounding and frequency compounding creates a layer of smoothed out electronic noise that is analogous to fog in photographic images. A novel approach to enhance ultrasound image contrast based on a modified dark channel model used to dehaze photographs is presented. Local minimum intensity is used to highlight image contrast, control influence of noise layer and improve detail resolution by different levels. The experimental results show that the proposed method has better performance over the existing methods in improving the quality of the ultrasonic image.
Hue‐preserving gamut mapping with high saturation
Authors: Yang S. , Lee B.
Published: September 2013

Preserving hue is an important issue for colour image enhancement. Here, a hue‐preserving gamut mapping method with high saturation is proposed. Experimental results with the Macbeth colour chart and natural images show vivid colour with higher subjective image quality.
Low‐complexity transcoding from H.264 to HEVC based on motion vector clustering
Authors: Jiang W. , Chen Y.W.
Published: September 2013

The forthcoming high efficiency video coding (HEVC) standard substantially improves the coding efficiency compared with the H.264 standard. It also brings in much higher computational complexity. Transcoding from H.264 to HEVC is an important step to enable gradual migration to HEVC. A low‐complexity H.264 to HEVC transcoding algorithm based on motion vector clustering is proposed. Experimental results show that the proposed algorithm can reduce up to 40% of the computational time compared to the original method, while maintaining a high rate‐distortion performance.
2.1 GHz MOS mixer linearisation approach for IIP2 enhancement using multiple factor compensation
Authors: Jiang J. , Holburn D.M.
Published: September 2013

An integrated downconversion CMOS mixer incorporating a comprehensive compensation scheme is presented which aims to minimise second‐order intermodulation distortion (IMD2). Unlike previously reported IMD2 calibration schemes which tune only one nonlinear factor at a time, the presented solution allows simultaneous adjustment of several different factors thus achieving a better compensation. The mixer has been implemented in UMC 0.18 µm CMOS to verify the proposed scheme and for comparison with alternative compensation methods. Measurements show that the solution described can improve the input intercept point (IIP2) by over 20 dB while maintaining good amplification and noise performance. IMD2 calibration results are presented and show useful advantages over other approaches. To the best of the authors' knowledge, this scheme for IMD2 calibration has not been previously reported.
Reliable communication envelopes of molecular diffusion channels
Authors: Guo W. , Wang S. , Eckford A. , Wu J.
Published: September 2013

Radio frequency communications are not always possible in hostile electromagnetic environments, and the molecular diffusion channel is considered as an information channel. A binary concentration modulated channel is considered and treated is the uncertain arrival time of particles as the main source of inter‐symbol interference. The analysis derives the bit‐error‐rate and data rate expressions for a diffusion channel with zero drift. The minimum error rate and maximum data rate are derived analytically. It is also found that in order for reliable communications to be possible, the delay time must be greater than a threshold that is proportional to the square of the communication distance.
Low‐complexity time‐domain linear equaliser for single‐carrier block transmissions
Authors: Ma C.‐Y. , Huang C.‐C.
Published: September 2013

Traditionally, frequency‐domain equalisers have been used to equalise the single‐carrier block transmission (SCBT) signals. However, to support the frequency‐domain equaliser, two fast Fourier transform modules are required, which will increase the circuit complexity and chip area. A low‐complexity time‐domain linear equaliser for SCBT is proposed, which is less complicated than conventional frequency‐domain equalisers, at the expense of an acceptable degradation in performance. For instance, for 60 GHz conference room non‐line‐of‐sight channels, the complexity can be reduced by half at the expense of a 1.5 dB performance loss.
Small‐area low‐ripple chopper instrumentation amplifier using sample‐and‐hold circuit
Authors: Seol H.‐C. , Kwon Y.‐C. , Kwon O.‐K.
Published: September 2013

A small‐area low‐ripple chopper instrumentation amplifier (IA) using a sample‐and‐hold circuit is proposed. The proposed chopper IA employs a ripple‐reduction loop (RRL) to suppress chopper ripple which is generated by the up‐modulated offset and 1/ƒ noise. The conventional RRL is not area‐efficient since a sensing capacitor occupies a large chip area. Thus, the RRL using the sample‐and‐hold circuit to reduce the chip area is proposed. The proposed chopper IA is fabricated by using a 0.18 μm CMOS process technology and has a smaller chip area of 0.054 mm2 than that of the state‐of‐the‐art design. The measured input‐referred ripples with and without the proposed RRL are less than 3.12 mV and 67 μV, respectively.
Impact of dynamic variability on the operation of CMOS inverter
Authors: Ioannidis E.G. , Haendler S. , Manceau J.‐P. , Dimitriadis C.A. , Ghibaudo G.
Published: September 2013

The impact of dynamic variability due to low‐frequency fluctuations on the operation of CMOS inverters, which constitute the basic component of SRAM cell, is investigated. The experimental methodology to characterise the effect of dynamic variability in a CMOS inverter is first established based on fast I–V measurements of the load current following the application of a ramp input voltage Vin(t). It is shown that, for small ramp rise times, the load current characteristics IDD(Vin) exhibit a huge sweep‐to‐sweep dispersion due to low‐frequency noise. The impact of such dynamic variability sources on the inverter's output characteristics Vout(Vin) is finally demonstrated, revealing a 20% noise margin reduction for the smallest inverter cell.
Compact wideband lumped balun with out‐of‐band suppression using tail inductor
Authors: Ye Yu , Li Lingyun , Gu Jianzhong , Sun Xiaowei
Published: September 2013

A novel compact 2.45 GHz wideband lumped balun with out‐of‐band suppression using a tail inductor has been proposed. By adding an extra transmission zero in even‐mode around operation frequency, the tail inductor can improve phase balanced performance and enlarge operational bandwidth of the balun. Besides, the tail inductor together with a band‐stop resonator can realise out‐of‐band transmission zero in even‐mode. The measured results illustrate a relative 41% bandwidth, namely from 2.35 to 3.35 GHz. Over the operation frequency, a less than 0.5 dB amplitude imbalance and a less than ± 7° phase error have been demonstrated. The out‐of‐band suppressions of two output ports at 5.3 GHz are 24.5 and 27.5 dB, respectively.
New compact Ka‐band CPW rat‐race coupler using GaAs MMIC technology
Authors: Chang C.‐L. , Tseng C.‐H.
Published: September 2013

A new compact Ka‐band rat‐race coupler (RRC) is proposed and fabricated in the 0.15‐μm GaAs pHEMTs process. Since the developed RRC is implemented by asymmetrical coplanar‐waveguide T‐structures, it has a compact circuit footprint and a return‐loss bandwidth similar to that of the conventional coupler. Besides, a short‐circuited quarter‐wave stub is attached into the ring of the RRC to flatten the output phase responses. The developed coupler has a 47.28% 10‐dB return‐loss bandwidth and only occupies a 20.89% circuit size of the conventional one. By considering the 180° ± 5° phase difference, the frequency range covers from 28.73 to 39.53 GHz with a 31.6% relative bandwidth. Over this frequency range, the amplitude imbalance varies from − 0.269 to 0.8 dB.
Fast iterative contourlet thresholding for compressed sensing MRI
Authors: Hao Wangli , Li Jianwu , Qu Xiaobo , Dong Zhengchao
Published: September 2013

Proposed is the use of the contourlet as a sparse transform which is combined with the fast iterative shrinkage/threshold algorithm (FISTA) for compressed sensing magnetic resonance imaging reconstruction. The proposed method not only inherits the simplicity and effectiveness of the original FISTA but also has the sparse curve representation ability of the contourlet. Simulation results validate the superior performance of the proposed method in terms of reconstruction accuracy and computation time.
Broadband wavelength swept source combining a quantum dot and a quantum well SOA in the wavelength range of 1153–1366 nm
Authors: Jang Wooyoung , Lim Jaeguyn , Kim Hongsig , Ha Jinyong
Published: September 2013

A wide tuning range wavelength swept laser for high axial resolution optical coherence tomography reported. Here, a parallel configuration of a quantum dot semiconductor optical amplifier (SOA) and a quantum well SOA is utilised for broadband optical source. The total scanning range of over 210 nm (192 nm at 10 dB) from 1153 to 1366 nm is reported. To investigate the feasiblity of the swept light source, demonstrated is an optical frequency domain imaging (OFDI) system. The system sensitivity of 101 dB is reported and axial resolution of 6.0 µm in air is achieved. Finally, ex vivo OFDI imaging of human breast tissue is performed.
Electro‐optic SSB modulator with 90° hybrid directly prepared onto LiNbO3 substrate
Authors: Enokihara A. , Kawamura K. , Nakao T. , Yamamoto K. , Kawai T. , Kawanishi T.
Published: September 2013

Optical single‐sideband (SSB) modulation is theoretically realised by applying two modulation signals with a 90° phase difference to the dual‐electrode type electro‐optic (EO) modulator. A branch‐line coupler (BC) as the microwave 90° hybrid was directly prepared on the EO modulator substrate, LiNbO3, to create two modulation signals from a single input signal. Output ports of the BC were connected to the modulation electrodes on the substrate. Thereby, an EO optical SSB modulator was realised with a single‐tip and a small‐sized configuration. The SSB modulator was designed and fabricated for around 10 GHz modulation frequency and 1550 nm light wavelength. The optical SSB modulation operation with a sideband suppression ratio of more than 20 dB was confirmed by the experiment.
Circularly‐polarised high gain cavity antenna based on sequentially rotated phase feeding
Authors: Ju J. , Kim D.
Published: September 2013

A Fabry‐Pérot cavity (FPC) array antenna providing both very high gain and circularly‐polarised (CP) behaviour is proposed. To increase antenna gain and to obtain the CP characteristic, a superstrate is introduced above 2 × 2 feeding microstrip patch antennas (MPAs), which converts linearly‐polarised (LP) incident waves to CP waves. Input phase difference between MPAs is designed to be exactly 90° to generate the high‐quality CP characteristic in cooperation with the superstrate. By using the FPC, very high gain can be obtained with only a small number of feeders, which also provides another advantage of low mutual coupling among the neighbouring MPAs. Although the proposed antenna is very simple in its structure, it readily provides very high gain, high‐quality CP property and very low axial ratio in a wide frequency range, which are great advantages compared with conventional CP antennas.
Paired T‐element design for multiple‐state acknowledge dependency
Authors: Taylor R.A. , Reese R.B.
Published: September 2013

A paired T‐element that assists in successfully controlling a dual‐rail delay‐insensitive asynchronous circuit system that implements multiple states containing acknowledge networks, that are interdependent, is presented. A T‐element allows triggering of next‐state actions concurrently with negation of its acknowledge input. However, this introduces a timing assumption that can cause system failure if it is violated. With little additional overhead, the paired T‐element is designed to combine the functionality of two standard T‐elements and allow adjacent reads to take place when there are inter‐state dependencies. This component successfully overlaps advantages of the performance optimisation of the original T‐element with the safety of the solution to this control scenario, making it an important element to be used in dual‐rail delay‐insensitive asynchronous circuit systems.
SiGe 135‐GHz amplifier with inductive positive feedback operating near fmax
Authors: Kim Hyunchul , Yun Jongwon , Song Kiryong , Rieh Jae‐Sung
Published: September 2013

A common base five‐stage D‐band amplifier developed in a 0.18‐μm SiGe HBT technology is presented. An inductive positive feedback technique is employed to enhance the gain, leading to 12.2 dB peak gain at 135 GHz with a power consumption of 67.2 mW. Measured output saturated power was − 5.8 dBm. The total chip area including pads is 1.54 × 0.56 mm2.
K‐band 0/180° balanced phase shifter with dc‐offset cancellation
Authors: Lee H.L. , Moon S.‐M. , Dong H.‐J. , Lee M.‐Q. , Yu J.‐W.
Published: September 2013

K‐band 0°/180° phase shifter MMIC based on balanced structure which can be applied to BPSK or QPSK modulator with dc‐offset cancellation is presented. The proposed balanced phase shifter consists of four Lange couplers, two quarter‐wave transmission lines and four switches for open and short terminations. The proposed structure implemented in GaAs 0.15‐µm low noise pHEMT process ensures stable 0/180° phase shift while common‐mode signals due to the mismatch in reflections by open and short are fed to the isolation port. The proposed phase shifter is verified by the phase shift of 179 ± 1.5° with the insertion loss of 4.5 ± 0.8 dB from 17.5 to 22.5 GHz. The fabricated phase shifter size is 2.2 × 2.85 mm including test pads.
Reduced‐complexity local switch based multi‐mode QC‐LDPC decoder architecture for Gbit wireless communication
Authors: Ajaz S. , Lee H.
Published: September 2013

A low‐complexity low‐power multi‐mode quasi‐cycle low‐density parity check decoder architecture for 60‐GHz Gbit wireless communication is presented. A novel, dynamic column shifting scheme is introduced for a multi‐mode architecture that provides a low complexity and fixed throughput across all rates. Novel low‐complexity local switch architecture and its control values are described to implement the dynamic shifting scheme. Post‐layout results show that the proposed architecture has low power consumption at high throughputs. It reduces about 57% memory and 31% area requirement compared to previously reported architecture.
Robust adaptive beamforming using beam‐space steering vector estimation
Authors: Yang T. , Su T. , Zhu W.T. , Zhang L.
Published: September 2013

To solve the problem of performance degradation owing to imprecise knowledge of the array steering vector and inaccurate estimation of the sample covariance matrix, a novel algorithm based on beam‐space steering vector estimation for robust adaptive beamforming is presented. By using the complementary set of the spatial sector in which the actual steering vector lies, a beam‐space transformation matrix can be constructed to remove the signal of interest from the sampling covariance matrix. The beam‐space steering vector is estimated by solving a non‐convex quadratically constrained quadratic optimisation problem. The effectiveness and robustness of the proposed algorithm is verified by the simulations.
Inductive sparse subspace clustering
Authors: Peng Xi , Zhang Lei , Yi Zhang
Published: September 2013

Sparse subspace clustering (SSC) has achieved state‐of‐the‐art clustering quality by performing spectral clustering over an ℓ1‐norm based similarity graph. However, SSC is a transductive method, i.e. it cannot handle out‐of‐sample data that is not used to construct the graph. For each new datum, SSC requires solving n optimisation problems in O(n) variables, where n is the number of data points. Therefore, it is inefficient to apply SSC in fast online clustering and scalable grouping. An inductive spectral clustering algorithm called inductive SSC (iSSC) is proposed, which makes SSC feasible to cluster out‐of‐sample data. iSSC adopts the assumption that high‐dimensional data actually lie on the low‐dimensional manifold such that out‐of‐sample data could be grouped in the embedding space learned from in‐sample data. Experimental results show that iSSC is promising in clustering out‐of‐sample data.
FPGA based flexible UWB pulse transmitter using EM subtraction
Authors: Strackx M. , Faes B. , D'Agostino E. , Leroux P. , Reynaert P.
Published: September 2013

An all‐digital field programmable gate array based electromagnetic subtraction technique for direct UWB pulse generation is presented. Using this technique, it is possible to generate Gaussian pulses, monocycles or doublets with high flexibility using a single printed circuit board layout. User‐controlled parameters include amplitude, pulse‐width, pulse‐type, repetition rate or even modulation. Measurements indicate a Gaussian pulse with 1.24 V peak amplitude and a 10% pulse‐width of 670 ps can be transmitted at a repetition frequency of 100 MHz. The corresponding − 10 dB bandwidth is 2.8 GHz.
NanoFS: a hardware‐oriented file system
Authors: Ruiz‐de‐Clavijo P. , Ostúa E. , Juan J. , Bellido M.J. , Viejo J. , Guerrero D.
Published: September 2013

NanoFS is a novel file system for embedded systems and storage‐class memories (like flash) and is specially designed to be directly implemented in hardware. NanoFS is based on an original internal layout intended to achieve an optimal hardware implementation of the file system's file lookup and data fetch operations. File system specification on a sample reader module completely implemented in a programmable device is introduced.
Reconfigurable fully digital transmitter with carrier‐frequency pulse‐width modulation
Authors: Zhou B. , Zhang K. , Zhou W. , Liu D.
Published: September 2013

A reconfigurable fully digital transmitter with carrier‐frequency (CF) pulse‐width modulation (PWM) is implemented in 180 nm CMOS for low CF applications. Through delay lines, baseband phases are mapped to position delays of 1/4 period of a carrier clock. With delay lines based CF PWM, pre‐corrected baseband envelopes are converted to pulse‐widths of the position‐modulated carrier clock. Both the pulse‐widths and the positions of the modulated carrier clock are amplified and reshaped to the sine‐wave carrier with baseband components by the sequent switched‐mode power amplifier and a bandpass filter. The circuit‐level simulation results verify that the proposed implementation achieves reconfigurable CF and 20 dB spectrum optimisation, when compared with the existing intermediate‐frequency PWM based designs.
New de‐embedding method to measure the RF input impedance of grid‐powered devices
Authors: Kasmi C. , Hélier M. , Darces M. , Ricordel P.‐M.
Published: September 2013

The power grid is a particular case for electromagnetic compatibility and interferences risk management because it presents a significant coupling area. The profusion of an electronic equipment connected to the network requires a control of the couplings to prevent any incident induced by a weak immunity of electronic devices to natural electromagnetic interferences in the environment or induced by EW‐, HPEM‐sources. It is of fundamental interest to estimate the maximal voltage (or current) magnitude induced on the power socket. The influence of loads and the transfer of energy between the power grid and the appliances require the characterisation of the electric and electronic devices. A new approach to achieve this task is proposed.
Non‐intrusive estimation of loss resistance of planar antenna over human body
Authors: Alves T. , Poussot B. , Laheurte J.‐M.
Published: September 2013

A new method is presented to estimate the loss resistance of antennas located slightly above a lossy medium. This technique is more specifically developed for the context of body area networks. This method is based on the estimation of the antenna resistance above the medium and above a perfect electric conductor.
SoftGait: compliant walking assistance via pneumatically actuated robot legs
Authors: Koo Donghan , Kim Byungjin , Kim Kyung‐Soo , Kim Soohyun
Published: September 2013

To assist the mobility handicapped, it is necessary to support their body weight in part using an assistive device. Since the human leg can be modelled by a spring during the gait, the assistive device (or robot) should have a certain level of compliance in order to achieve natural gait assistance. A pneumatic cylinder is added in parallel to a leg (which is also a spring) for antigravity with compliance. By simulation, the compliant gravity assistance effectively reduces the required forces and torques at the joints of leg. Using this idea, a prototype of an assistive robot named SoftGait is developed and experiments are performed to verify its efficacy.
Nanosecond pulse fibre laser based on nonlinear polarisation rotation effect
Authors: Anyi C.L. , Haris H. , Harun S.W. , Ali N.M. , Arof H.
Published: September 2013

A nanosecond pulse erbium‐doped fibre laser (EDFL) is demonstrated based on nonlinear polarisation rotation effect using a highly concentrated EDF in a ring cavity. The EDFL generates a stable multi‐wavelength comb with a constant spacing of 0.22 nm in the 1533.6 nm wavelength region at a pump power of 87.6 mW. A stable mode‐locked operation also commences with a constant repetition rate of 77 MHz with pulse width that varies from 5.3 to 6.8 ns as the pump power is increased from 87.6 to 168.9 mW. With careful adjustment of the polarisation controller, a stable square pulse is obtainable at a pump power of 128.3 mW with a pulse width of 6.5 ns and an average output power of 5.0 mW, which translates to the pulse energy of 35 pJ. The square pulse is generated based on the nonlinear polarisation switching effect inside the laser cavity.
Silicon‐based nanoplasmonic disc resonator on CMOS platform
Authors: Nielsen M.P. , Elezzabi A.Y.
Published: September 2013

The first demonstration of a silicon‐based metal–insulator–semiconductor (MIS) nanoplasmonic disc resonator monolithically integrated on a CMOS compatible platform is presented. The nanoplasmonic disc resonator is integrated with Au/SiO2/Si MIS nanoplasmonic waveguides and conventional silicon‐on‐insulator photonic waveguides. The device has a high plasmonic quality (Q) factor of 82.3, one of the highest reported for an integrated silicon‐based nanoplasmonic device, with a compact device footprint of only 4 µm2.
Transversal wideband bandpass filter using open/shorted coupled lines
Authors: Feng Wenjie , Che Wenquan
Published: September 2013

A novel fifth‐order wideband bandpass filter using open/shorted coupled lines is proposed. A wideband passband with eight transmission zeros from 0 GHz to 2f0 (f0 is centre frequency of the passband) can be achieved respectively due to the superposition of signals of the two transmission paths. A wideband bandpass filter prototype with 3‐dB fractional bandwidth of 62% (2.12–3.98 GHz) is designed and fabricated.
InAs/AlSb quantum cascade lasers operating near 20 µm
Authors: Bahriz M. , Lollia G. , Laffaille P. , Baranov A.N. , Teissier R.
Published: September 2013

InAs‐based quantum cascade lasers (QCLs) operating near 20 µm are demonstrated. A double metal waveguide fabricated by transfer of the laser active region onto a host InAs substrate has been employed in these devices. The threshold current density of 1.6 kA/cm2 at 80 K is lower than that of InP‐based QCLs emitting in the same spectral region. The lasers operated in pulsed mode up to 170 K.
Compact superconducting dual‐band bandpass filter by combining bandpass and bandstop filters
Authors: Heng Yong , Guo Xubo , Cao Bisong , Wei Bin , Zhang Xiaoping , Zhang Guoyong , Song Xiaoke
Published: September 2013

A superconducting dual‐band bandpass filter with a mixture of bandpass and bandstop sub‐filters is presented. The bandpass sub‐filter is designed with λ/2 double spiral resonators mid‐tapped by λ/4 connecting lines which act as admittance inverters. The tap position of each resonator is adjusted to meet the required susceptance slope parameter. The bandstop sub‐filter is designed with λ/2 folded resonators embedded in and coupled with the centres of the λ/4 connecting lines. The dual‐band filter is designed and fabricated on an LaAlO3 substrate with a compact size of 30.4 × 10.3 mm. The measurements show good dual‐band response and match well with the simulations.
Antenna design exploiting duplex isolation for 4G application on handsets
Authors: Caporal Del Barrio S. , Pedersen G.F.
Published: September 2013

A novel design addressing the antenna bandwidth issue for future communication standards on handsets is presented. It consists of a tunable‐antenna‐pair for operation with a tunable front‐end. The antennas are narrow‐band and frequency‐reconfigurable. This Letter focuses on the low communication bands. Measurements of the design are shown in band 12, and exhibit a receiver–transmitter isolation above 25 dB at 700 MHz.
Embedding holistic appearance information in part‐based adaptive appearance model for robust visual tracking
Authors: Zeng F.X. , Huang Z.T. , Ji Y.F.
Published: September 2013

Part‐based adaptive appearance model has been extensively used in increasingly popular discriminative trackers. The main problem of these methods is the stability plasticity dilemma. Embedding holistic appearance information in the part‐based appearance model which is learned online to alleviate this problem is proposed. Specifically, the object is represented by sparse multi‐scale Haar‐like features and the appearance model is constructed with a naive Bayes classifier. Unlike the conventional methods, the classifier is trained by positive and negative samples that are weighted according to their similarity with the holistic appearance model, which is kept constant during the updating procedure. The constant holistic appearance information providing some constraints when updating the part‐based appearance model makes the tracker more stable. The online updating procedure of the part‐based appearance model makes the tracker adaptive enough to appearance changes. Experimental results demonstrate the superior performance of the proposed method compared with several state‐of‐art algorithms.
Fault‐tolerant control design for uncertain Takagi–Sugeno systems by trajectory tracking: a descriptor approach
Authors: Bouarar Tahar , Marx Benoit , Maquin Didier , Ragot José
Published: September 2013

This study considers the problem of fault‐tolerant control (FTC) by trajectory tracking for uncertain non‐linear system described by Takagi–Sugeno models. The considered faults are constant, exponential or polynomial. The provided results are easily formulated in terms of linear matrix inequalities by employing the descriptor redundancy property. This latter introduces ‘virtual’ dynamics both in the active FTC control law scheme and in the output error allowing to decouple the gains of the active FTC controller, the observer gain matrices and the system ones. Numerical examples are given to illustrate the efficiency of the proposed approach.
Backstepping control of multi‐input non‐linear systems
Authors: Chung Chien‐Wen , Chang Yaote
Published: September 2013

A methodology of designing the block backstepping controller for a class of multi‐input non‐linear perturbed systems is proposed to solve the regulation problem in accordance with the Lyapunov stability theorem. The designed constant gains, which are embedded in the virtual input controllers, can effectively overcome more general mismatched perturbations than some works can. Furthermore, the asymptotical stability can be achieved by the proposed controller. Finally, an example of controlling the control‐moment‐gyro devices is used to demonstrate the feasibility of the proposed methodology.
Matrix form of the Bi‐CGSTAB method for solving the coupled Sylvester matrix equations
Authors: Hajarian Masoud
Published: September 2013

The bi‐conjugate gradient stabilised (Bi‐CGSTAB) method is one of the efficient computational tools to solve the non‐Hermitian linear systems Ax  = b. By employing Kronecker product and vectorisation operator, this study investigates the matrix form of the Bi‐CGSTAB method for solving the coupled Sylvester matrix equations ∑i =1k(Ai XBi + Ci YDi) = M, ∑i =1k(Ei XFi + Gi YHi) = N [including (second‐order) Sylvester and Lyapunov matrix equations as special cases] encountered in many systems and control applications. Several numerical examples are given to compare the efficiency and performance of the investigated method with some existing algorithms.
Trend towards the design of embedded DC–DC converters
Authors: Bhattacharyya Kaushik
Published: September 2013

These days, embedded DC–DC converters are paying a remarkable attention to the research and consumer domain. The concept is basically conceived into the need of miniaturised, lightweight, highly power dense solution. This study surveys the DC–DC converters aiming towards the trend of design of embedded converters. Starting from the conventional inductor‐based converters to the present trend of design of embedded DC–DC converters are discussed here. Here, all the issues which may play important role during the design of above converters are elaborated and possible remedies to mitigate the issues to achieve the better performance are also illustrated. A brief idea towards the possible future research direction on embedded converters is also discussed here.
High‐power‐factor light‐emitting diode lamp power supply without electrolytic capacitors for high‐pressure‐sodium lamp retrofit applications
Authors: Alonso J. Marcos , Calleja Antonio J. , Gacio David , Cardesín Jesus , Lopez Emilio , Dalla Costa Marco Antonio , da Silva Marcelo Freitas , do Prado Ricardo Nederson
Published: September 2013

A long‐life high‐power‐factor integrated converter able to supply light‐emitting diode (LED) lamps in high‐pressure‐sodium lamp retrofitting applications is presented. The proposed converter is the integration of a buck‐boost converter with a buck converter, thus providing the necessary high input power factor and voltage transformation ratio to supply the low‐voltage LED array from the mains. The analysis of the converter is carried out, and a design procedure is proposed. The design is also performed so that low capacitances are needed at the output of each semi‐stage. This allows for the use of long‐life film capacitors, thus matching the converter lifetime to that of the LED lamp. A laboratory prototype supplied from 230 Vrms/50 Hz mains used to drive two LED arrays in series with a total output power of 100 W is presented.
Volt‐second‐based control method for discontinuous conduction mode flyback micro‐inverters to improve total harmonic distortion
Authors: Zengin Sinan , Deveci Fırat , Boztepe Mutlu
Published: September 2013

Flyback‐type micro‐inverter is an attractive solution for photovoltaic ac‐module applications because of several advantages; such as simple current control, working without ac current sensor and potentially low cost. However, it suffers from the dc‐link voltage ripple that causes it to merge with the third and fifth harmonics on the output current. For this reason, a very smooth dc‐link voltage is essential in order to keep total harmonic distortion (THD) at a low level. However, the voltage ripple is inevitable in practise for single‐phase inverters because of pulsating instantaneous power. This study presents a new volt‐second‐based current control method for flyback micro‐inverters which improves THD caused by the voltage ripple. The proposed method works effectively up to approximately 20% of the dc‐link voltage ripple. In addition, the volt‐second‐based control method is able to allow reduction of the power decoupling capacitor value. Experimental results validating the proposed method are also presented.
Predictive variable‐structure system control of unity power factor rectifiers
Authors: Korelič Jože , Jezernik Karel
Published: September 2013

This study presents the design of a current control loop and the selection of switching logic for pulse‐width modulation (PWM) of three‐phase switching converters. This approach is based on a deliberate introduction of the predictive sliding mode motion within a control system. It shows that the selection of the PWM pattern is a direct result of sliding mode existence within the current control closed‐loop system. The design specifications are robustness to load electrical parameters, fast dynamic response, reduced switching frequency and simple hardware implementation. To meet previous specifications, a sliding mode controller has been developed, designed as a finite state machine, and implemented within a field programmable gate array device. The switching strategy implemented within the state transition diagram provides for a minimum number of switch state changes by the three‐phase converter that is confirmed through simulation and experimental results.
Low computational burden grid voltage sensorless current controller
Authors: Gomez Jorge Sebastian , Busada Claudio Alberto , Solsona Jorge
Published: September 2013

This study proposes a grid voltage sensorless reduced order generalised integrator‐based current controller. The proposal takes advantage of the controller structure to avoid the grid voltage measurement, avoiding the need of additional states and requiring only a few multiply and add operations for its computation. This allows one to keep the controller's computational burden to a minimum, making it ideal for low cost digital signal processor implementation.
Hysteresis current controller for a general n‐level inverter fed drive with online current error boundary computation and nearly constant switching frequency
Authors: Dey Anubrata , Azeez Najath Abdul , Mathew Kallarackal , Gopakumar Kumarukattan Nair , Kazmierkowski Marian P.
Published: September 2013

A space vector‐based hysteresis current controller for any general n‐level three phase inverter fed induction motor drive is proposed in this study. It offers fast dynamics, inherent overload protection and low harmonic distortion for the phase voltages and currents. The controller performs online current error boundary calculations and a nearly constant switching frequency is obtained throughout the linear modulation range. The proposed scheme uses only the adjacent voltage vectors of the present sector, similar to space vector pulse‐width modulation and exhibits fast dynamic behaviour under different transient conditions. The steps involved in the boundary calculation include the estimation of phase voltages from the current ripple, computation of switching time and voltage error vectors. Experimental results are given to show the performance of the drive at various speeds, effect of sudden change of the load, acceleration, speed reversal and validate the proposed advantages.
Autonomous operation of ac–dc microgrids with minimised interlinking energy flow
Authors: Loh Poh Chiang , Li Ding , Chai Yi Kang , Blaabjerg Frede
Published: September 2013

Modern distributed sources can either be ac or dc. It is thus possible to form hybrid microgrids with both ac and dc sub‐grids inter‐tied by power converters. The resulting hybrid architecture allows loads to be flexibly placed, hence reducing the amount of power conversion needed. Hybrid microgrids can therefore be more efficient if controlled appropriately. For that, a droop scheme is now proposed for coordinating energy flows within the hybrid microgrids. The scheme operates autonomously and efficiently without demanding for fast communication links. The overall energy flow tuning and hybrid microgrids have already been tested in experiments.
A new in situ electrical calibration system for high temperature Calvet calorimeters
Authors: Razouk Refat , Hay Bruno , Himbert Marc
Published: September 2013

A new in situ high temperature electrical calibration system was developed at Laboratoire National de Metrologie et d’Essais, Laboratoire Commun de Metrologie and integrated into a heat flux Calvet calorimeter in order to perform accurate and reliable measurements of enthalpy of fusion that are directly traceable to the International System of Units (SI). This system has been designed to enable the calibration of the calorimeter by electrical substitution (Joule effect) as well as the measurement of enthalpy of fusion in perfectly identical experimental conditions. The metrological features (repeatability, linearity, etc.) of the calorimeter have been evaluated with this system by investigating the influence of some parameters (level of energy, dissipation time, and temperature) on the determination of the sensitivity factor of its thermopiles. Two different procedures, for the calibration and the enthalpy measurements with this new electrical calibration system, have been implemented and tested by measuring the enthalpy of fusion of high purity 6N tin. The results obtained are in very good agreement with those measured by other National Metrology Institutes on the same material.
Magnetic properties of monolayer range chromium oxides on Fe(001)
Authors: Brambilla A. , Berti G. , Calloni A. , Picone A. , Riva M. , Bussetti G. , Nappini S. , Magnano E. , Finazzi M. , Duò L. , Ciccacci F.
Published: September 2013

Cr ultrathin films have been prepared on the oxygen-passivated Fe(001)-p(1 × 1)O surface, resulting in monolayer range chromium oxide layers. We discuss the presence of first nearest-neighbor Cr pairs, as seen by scanning tunneling microscopy, in the early stages of interface growth and compare the results with previous experimental observations on the Cr/Fe oxygen-free interface. We then derive the magnetic properties of the Cr oxide ultrathin films by analyzing new x-ray magnetic circular dichroism measurements conducted on samples grown both at room temperature and at 400 °C. The ultrathin Cr oxide film forms in both cases a ferromagnetic layer which is antiferromagnetically coupled to Fe.
Optimal placement and sizing of plug in electric vehicles charging stations within distribution networks with high penetration of photovoltaic panels
Authors: Pashajavid E. , Golkar M. A.
Published: September 2013

This paper proposes a scenario optimization based algorithm in order to allocate charging station of plug in electric vehicles (PEVs) within a commercial area with the aim of increasing penetration level of photovoltaic (PV) panels as well as decreasing side effects of vehicular loads. A multivariate stochastic modeling methodology based on the notion of copula is provided in order to develop a probabilistic model of the load demand due to PEVs. The suggested method considers the correlation issue among the related random variables of the PEVs. This model, in addition to the models provided for PV generation and commercial loads, is utilized to construct synthetic data required for the optimal allocation of the station. Considering the prepared scenarios, particle swarm optimization (PSO) algorithm is utilized to minimize energy loss as well as voltage deviation in the distribution system. The proposed methodology has been applied on a test distribution network in order to demonstrate its efficiency in simultaneous integration of vehicular loads and PV generations.
Emitting waves from heterogeneity by a rotating electric field
Authors: Zhao Ye-Hua , Lou Qin , Chen Jiang-Xing , Sun Wei-Gang , Ma Jun , Ying He-Ping
Published: September 2013

In a generic model of excitable media, we simulate wave emission from a heterogeneity (WEH) induced by an electric field. Based on the WEH effect, a rotating electric field is proposed to terminate existed spatiotemporal turbulence. Compared with the effects resulted by a periodic pulsed electric field, the rotating electric field displays several improvements, such as lower required intensity, emitting waves on smaller obstacles, and shorter suppression time. Furthermore, due to rotation of the electric field, it can automatically source waves from the boundary of an obstacle with small curvature.