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A one-eighth spherical surface dielectric resonator antenna (OESS-DRA) is proposed first time. To analyze this thin shell structure, electromagnetic fields distribution is discussed by using the Hertz vector and boundary conditions. We simplify the solution of Maxwell equations by using Hertz vector because the polarization current is primary in the OESS-DRA. The Hertz vector can be expressed the current better. This proposed antenna is composed of one-eighth spherical dielectric shell fed by coaxial probe; and the ground with metal-corner-reflector makes the antenna with high gain and directional radiation properties. To verify this design, a fabricated sample is tested; results show the antenna covering bandwidth 4.56-6.88GHz, a high gain greater than 9.5dBi (peak gain 11.8dBi at 5.0GHz), and a high radiation efficiency over 85% in the entire working frequency band, as well. The OESS-DRA can be a good candidate in 5th generation communication applications.

Background: Globus pallidus internus (GPi) deep brain stimulation (DBS) and thalamotomy are interventions for writer’s cramp (WC). Ventralis intermedius nucleus (VIM) DBS is targeted for tremor, however, many aspects of VIM DBS remained underexplored in WC. Case Report: A 62-year-old man with WC underwent DBS. Dystonic tremor improved intraoperatively with ventralis oralis anterior (VoA)/ventral oralis posterior (VoP) and with subthalamic nucleus stimulation; although greatest benefit was obtained with VIM stimulation. Sustained benefit with VIM DBS at ten months post-operative was obtained. Discussion: This case demonstrates an intraoperative approach in target selection and supports benefits of VIM DBS for WC. Highlights: This case highlights the intraoperative approach and clinical effects of VIM DBS in the treatment of medically refractory writer’s cramp (WC). We contextualize our results from this case with previous reports of VoA/VoP stimulation for WC.

A directional two-element mm-wave dipole antenna array with reconfigurable patterns is presented in this paper. An substrate integrated waveguide (SIW) 90° coupler is used to realize reconfigurable patterns of the antenna array. The two dipole elements are parallel in space, and there is a distance of λ0/4 (λ0 is the wavelength of the free space) between them. When the two inputs of the 90° coupler are excited, respectively, two completely opposite radiation patterns are able to be achieved. In order to further enhance the directivity of the proposed antenna, two groups of novel zero-index metamaterials and three metallic strips are introduced. As a consequence, a 0.7-1.2 dBi gain enhancement and reduced back lobe are obtained within the working frequencies. The measured amplitudes of S11 and S22 are below -10 dB from 45.5 to 49.5 GHz, and the measured gain is all great than 5 dBi within this band.

BACKGROUND Acute dyskinesias elicited by STN-DBS, here referred to as stimulation-induced dyskinesias, predict optimal clinical outcome in PD. However, it remains elusive whether stimulation-induced dyskinesias can guide DBS programming. OBJECTIVES Here, we characterized stimulation-induced dyskinesias clinically and anatomically. We then tested whether dyskinesia-inducing contacts could be effectively programmed using independent current source technology. METHODS We characterized stimulation-induced dyskinesias with directional and ring stimulation retrospectively in 20 patients. We then localized dyskinesia-inducing contacts by imaging coregistration and eventually programmed those contacts. RESULTS We elicited dyskinesias in half of our patients. Dyskinesia-inducing contacts were mainly directional and were all located ventrally within the dorsolateral motor STN. When these dyskinesia-inducing contacts were programmed using independent current source technology, dyskinesia disappeared and robust antibradykinetic effects were obtained. CONCLUSION We confirm that stimulation-induced dyskinesias are helpful clinical observations, which may guide programming of directional STN-DBS in PD. © 2019 International Parkinson and Movement Disorder Society.

Our article proposes an application of the Directional Distance Function (DDF) approach to the fixed telecommunication field. In particular, we present an efficiency evaluation of European fixed telecom operators, where the DDF tool allows for asymmetric treatment of outputs characterized by a different degree of desirability: broadband lines (a market still in expansion, related to a welfare-improving service) and narrow band lines (an almost saturated market, corresponding to a "minimal" TLC service in developed countries). Finally, by means of a second stage regression, we investigate the effect on technical efficiency of set of variables representing the competitive environment, the ownership structure and the degree of vertical separation. Our results show that the assumptions embedded in the DDF model influence relevantly the technical efficiency estimates, where important potential bias can arise if the duality of outputs is ignored, with a subsequent relevant impact also on the second stage results. These findings highlight the relevance of choosing benchmarking models consistent with the features of the analysed technology and show that the DDF approach is a flexible tool able to accommodate even complex output structures. This work proposes an application of the DDF approach to the fixed TLC field.DDF allows for asymmetric treatment of differently desirable outputs.DDF assumptions influence the efficiency estimates and the second stage results.DDF is a flexible tool allowing benchmarking even with complex output structures.

The article of record as published may be found at http://dx.doi.org/10.1117/12.2244387 The conventional directional sound sensing systems employ an array of spatially separated microphones to achieve directional sensing. However, there are insects such as Ormia ochracea fly that can determine the direction of sound using a miniature hearing organ much smaller than the wavelength of sound it detects. The MEMS based sensors mimicking the fly’s hearing system was fabricated using SOI substrate with 25 micrometer device layer. The sensor was designed to operate around 1.7 kHz, consists of two 1.2 mm x1.2 mm wings connected in the middle by a 3 mm x 30 micrometer bridge. The entire structure is connected to the substrate by two torsional legs at the center. The sensor operates at its bending resonance frequency and has cosine directional characteristics similar to that of a pressure gradient microphone. For unambiguously determining the direction of sound, two sensors were assembled with a canted angle and outputs of the two sensors were processed to uniquely locate the bearing. At the bending resonant frequency (1.7 kHz) an output voltage of about 25 V/Pa was measured. The uncertainty of the bearing of sound ranged from less than 0.3 degrees close to the normal axis (0 degree) to 3 degrees at the limits of coverage (± 60 degrees) based on the 30 degree canted angle used. These findings indicate the potential use of a dual MEMS direction finding sensor assembly to locate sound sources with high accuracy. ONR TDSI

Thermography is a non-destructive technique which uses infrared radiation to obtain the temperature distribution of an object. The technique is increasingly used in the pulp and paper industry. To convert the detected infrared radiation to a temperature, the emittance of the material must be known. For several influencing parameters the emittance of paper and board has not previously been studied in detail. This is partly due to the lack of emittance measurement methods that allow for studying the influence of these parameters.An angle-resolved goniometric method for measuring the infrared emittance of a material was developed in this thesis. The method is based on the reference emitter methodology, and uses commercial infrared cameras to determine the emittance. The method was applied to study the dependence on wavelength range, temperature, observation angle, moisture ratio, sample composition, and sample structure of the emittance of paper and board samples. It was found that the emittance varied significantly with wavelength range, observation angle and moisture ratio. The emittance was significantly higher in the LWIR (Long-Wavelength Infrared) range than in the MWIR (Mid-Wavelength Infrared) range. The emittance was approximately constant up to an observation angle of 60° in the MWIR range and 70° in the LWIR range, respectively. After that it started to decrease. The emittance of moist samples was significantly higher than that of dry samples. The influence of moisture ratio on the emittance could be estimated based on the moisture ratio of the sample, and the emittance of pure water and dry material, respectively.The applicability of measured emittance values was demonstrated in an investigation of the mechanical properties of sack paper samples. An infrared camera was applied to monitor the generation of heat during a tensile test of a paper sample. It was found that the observed increase in thermal energy at the time of rupture corresponded well to the value of the elastic energy stored in the sample just prior to rupture. The measured emittance value provided an increased accuracy in the thermal energy calculation based on the infrared images.

We describe the numerical implementation of a phase-resolving, nonlinear spectral model for shoaling directional waves over a mild sloping beach with straight parallel isobaths. The model accounts for non-linear, quadratic (triad) wave interactions as well as shoaling and refraction. The model integrates the coupled, nonlinear hyperbolic evolution equations that describe the transformation of the complex Fourier amplitudes of the deep-water directional wave field. Because typical directional wave spectra (observed or produced by deep-water forecasting models such as WAVEWATCH III™) do not contain phase information, individual realizations are generated by associating a random phase to each Fourier mode. The approach provides a natural extension to the deep-water spectral wave models, and has the advantage of fully describing the shoaling wave stochastic process, i.e., the evolution of both the variance and higher order statistics (phase correlations), the latter related to the evolution of the wave shape. The numerical implementation (a Fortran 95/2003 code) includes unidirectional (shore-perpendicular) propagation as a special case. Interoperability, both with post-processing programs (e.g., MATLAB/Tecplot 360) and future model coupling (e.g., offshore wave conditions from WAVEWATCH III™), is promoted by using NetCDF-4/HD5 formatted output files. The capabilities of the model are demonstrated using a JONSWAP spectrum with a cos2s directional distribution, for shore-perpendicular and oblique propagation. The simulated wave transformation under combined shoaling, refraction and nonlinear interactions shows the expected generation of directional harmonics of the spectral peak and of infragravity (frequency &lt, 0.05 Hz) waves. Current development efforts focus on analytic testing, development of additional physics modules essential for applications and validation with laboratory and field observations.

High time resolution spectrum occupancy measurements and analysis are presented for 2.4 GHz WLAN signals. A custom-designed wideband sensing engine records the received power of signals, and its performance is presented to select the decision threshold required to define the channel state (busy/idle). Two sets of measurements are presented where data were collected using an omni-directional and directional antenna in an indoor environment. Statistics of the idle time windows in the 2.4 GHz WLAN are analyzed using a wider set of distributions, which require fewer parameters to compute and are more practical for implementation compared to the widely-used phase type or Gaussian mixture distributions. For the omni-directional antenna, it was found that the lognormal and gamma distributions can be used to model the behavior of the idle time windows under different network traffic loads. In addition, the measurements show that the low time resolution and angle of arrival affect the statistics of the idle time windows.

A photo-excited organic layer on a metal thin film with a corrugated substrate was used to generate surface plasmon grating coupled emissions (SPGCEs). Directional emissions corresponded to the resonant condition of surface plasmon modes on the Au/air interface. In experimental comparisons of the effects of different pitch sizes on the plasmonic band-gap, the obtained SPGCEs were highly directional, with intensity increases as large as 10.38-fold. The FWHM emission spectrum was less than 70 nm. This method is easily applicable to detecting refractive index changes by using SP-coupled fluorophores in which wavelength emissions vary by viewing angle. The measurements and calculations in this study confirmed that the color wavelength of the SPGCE changed from 545.3 nm to 615.4 nm at certain viewing angles, while the concentration of contacting glucose increased from 10 to 40 wt%, which corresponded to a refractive index increase from 1.3484 to 1.3968. The organic plasmon-emitting diode exhibits a wider linearity range and a resolution of the experimental is 1.056 × 10−3 RIU. The sensitivity of the detection limit for naked eye of the experimental is 0.6 wt%. At a certain viewing angle, a large spectral shift is clearly distinguishable by the naked eye unaided by optoelectronic devices. These experimental results confirm the potential applications of the organic plasmon-emitting diodes in a low-cost, integrated, and disposable refractive-index sensor.

Microgrid implementation draws new challenges especially in the coordination of protective devices that are not likely to appear in a traditional distribution network. Variation of fault current levels, bi-directional fault current and changing of microgrid operation modes make protection of the microgrids more difficult. In this work, a systematic procedure for coordination of different protection schemes is presented to secure the operation of a microgrid system. The procedure initially starts with coordination of overcurrent (OC) relays and followed by directional overcurrent (DOC) relays in the system. If the coordination of these two types of relays is unsatisfactory, then differential (DIF) relays are used to replace the OC relay in the faulty section. The proposed method takes into account device selectivity, sensitivity and proper protection function simultaneously. Simulation results show that the proposed coordination method safely protect a microgrid system during both grid-connected and islanded operation modes.

Traditional percutaneous balloon angioplasty and stent placement is based on mechanical plaque disruption and displacement within the arterial wall. On the contrary, transcatheter atherectomy achieves atherosclerotic plaque clearance by means of directional plaque excision or rotational plaque removal or laser plaque ablation. Debulking atherectomy may allow for a more uniform angioplasty result at lower pressures with consequently less vessel barotrauma and improved luminal gain, thereby decreasing the risk of plaque recoil and dissection that may require permanent metal stenting. It has been also argued that atherectomy may disrupt the calcium barrier and optimize drug transfer and delivery in case of drug-coated balloon applications. The authors discuss the various types of atherectomy devices available in clinical practice to date and critically appraise their mode of action as well as relevant published data in each case. Overall, amassed randomized and observational evidence indicates that percutaneous atherectomy of the femoropopliteal and infrapopliteal arteries may achieve high technical success rates and seems to lessen the frequency of bailout stenting, however, at the expense of increased risk of peri-procedural distal embolization. Long-term clinical outcomes reported to date do not support the superiority of percutaneous atherectomy over traditional balloon angioplasty and stent placement in terms of vessel patency or limb salvage. The combination of debulking atherectomy and drug-coated balloons has shown promise in early studies, especially in the treatment of more complex lesions. Unanswered questions and future perspectives of this continuously evolving endovascular technology as part of a broader treatment algorithm are discussed.

An autonomous vessel, the Offshore Sensing Sailbuoy, was used for wave measurements near the Ekofisk oil platform complex in the North Sea (56.5o N, 3.2o E, operated by ConocoPhillips) from 6 to 20 November 2015. Being 100 % wind propelled, the Sailbuoy has two-way communication via the Iridium network and has the capability for missions of 6 months or more. It has previously been deployed in the Arctic, Norwegian Sea and the Gulf of Mexico, but the present study was the first test for wave measurements. During the campaign the Sailbuoy held position about 20 km northeast of Ekofisk (on the lee side) during rough conditions. Mean wind speed measured at Ekofisk during the campaign was 9.8 m/s, with a maximum of 20.4 m/s, with wind mostly from south and southwest. A Datawell MOSE G1000 GPS-based 2 Hz wave sensor was mounted on the Sailbuoy. Mean significant wave height (H s 1 min) measured was 3 m, whereas maximum H s was 6 m. Mean wave period was 7.7 s, while maximum wave height, H max, was 12.6 m. These measurements have been compared with non-directional Waverider observations at the Ekofisk complex. The agreement between the two data sets was very good, with a mean percent absolute error of 7 % and a linear correlation coefficient of 0.97. The wave frequency spectra measured by the two instruments compared very well, except for low H s (∼1 m), where the motion of the vessel seemed to influence the measurements. Nevertheless, the Sailbuoy performed well during this campaign, and results suggest that it is a suitable platform for wave measurements in a broad range of sea conditions.

Fault Passage Indicators (FPIs) are a cost effective solution to increase grid reliability. The connection of Distributed Generation units can lead them to misoperate and undermine the reliability improvements. Directional FPIs is a solution to overcome this problem. In this paper, the fault detection methods and direction-polarization principles for an isolated grid are described. As well, the implementation is done in Matlab-Simulink, from the signal processing techniques till the logic scheme for fault confirmation and automated reset. Some simulations are conducted to evaluate the performance of such FPI. ispartof: pages:2075-2080 ispartof: IECON-2013 pages:2075-2080 ispartof: IECON location:Viena, Austria date:10 Nov - 13 Nov 2013 status: published

Significant research has been performed on the use of directional transforms for the compression of still imagery, in particular on the application of block-based and segmentation driven directional adaptive discrete wavelet transforms. However, all of the proposed methodologies suffer from the extra side-information that needs to be encoded. This encoding overhead and added complexity is unfortunately not negligible. This paper describes various considerations and trade-offs that were made during the search towards a practical solution for using directional adaptive transforms in still image coding. We propose two codec instantiations respectively based upon quadtree-coding (QT-L) and JPEG 2000's EBCOT engine and discuss various experimental results.

The potential for directional optical and thermal imagery is very large. Field measurements have been performed with a goniometer on which thermal instruments were attached. In order to reduce dynamical effects the goniometer was adjusted to run in automated mode, for zenith and azimuthal direction. Directional measurements were performed over various crops with increasing heterogeneity. The improvements to the goniometer proved successful. For all the crops, except the vineyard, the acquisition of the directional thermal brightness temperatures of the crops went successfully. The large scale heterogeneity of the vineyard proved to be larger then the goniometer was capable of. The potential of directional thermal brightness temperatures has been proven.

In this paper, I explore the combination possibilities of Bulgarian directional prefixes with various motion verbs. Adopting Ramchand’s (in press) event decomposition, Zwarts’ (2005) vector space semantics for directional prepositions, and drawing on various discussions regarding the manner component in the verbal meaning, I propose an analysis that captures the distribution of Goal and Source prefixes. I show how this proposal accounts for the change in the syntactic behavior of prefixed motion verbs compared to their unprefixed counterparts. The proposal also explains the syntactic properties exhibited by verbs when prefixed by different prefixes. I offer a unified treatment of path structure and event structure and suggest that directional prepositions and directional prefixes are semantically identical and originate in the extended PP. The differences between them are due to the syntactic structure in which they participate.

In this paper I present the prepositional system in Persian. I show that Persian prepositions can be divided into three classes (Class 1, Class 2a and Class 2b) which exhibit distinct syntactic behavior. Then I examine the question of the categorial status of Class 2 prepositions and demonstrate that they are not to be regarded as nouns. Finally I present the extended PP projection of Persian spatial prepositions and argue for a feature-based analysis of the properties they manifest.

Summary The importance of wellbore deviation is well recognized by the drilling industry. An analysis of a drilling system's directional behavior must include the directional characteristics of the drill bit. This paper presents a comprehensive analysis of the directional behavior of polycrystalline diamond compact (PDC) bits, including the effect of bit profile, gauge cutters, and gauge length. Numerical simulations as well as laboratory tests have been carried out to better understand the mechanisms of PDC bit deviation and to evaluate the most important parameters affecting the directional behavior of PDC bits. The analysis presented in this paper shows that each part of the PDC bit (profile and active and passive gauges) plays a major role in its walking tendency and steerability. A quantitative evaluation of how these factors contribute to well trajectory (inclination and azimuth) is given. For the first time, a full-scale directional-drilling bench was built to measure the walking tendency and steerability of PDC bits. The results obtained demonstrate that the bit profile, gauge cutters, and gauge length have a significant effect. A 3D theoretical rockbit interaction model was developed to reproduce the drilling test results.

The importance of wellbore deviation is well recognized by the drilling industry. An analysis of the directional behaviour of a drilling system must include the directional characteristics of the drilling bit. A comprehensive analysis of the directional behaviour of PDC bits is presented in this paper, including the effect of bit profile, gage cutters and gage length. Numerical simulations as well as laboratory tests have been carried out in order to better understand the mechanisms of PDC bits deviation and to evaluate the most important parameters affecting the directional behaviour of PDC Bits. The analysis of the directional behaviour of PDC bits presented in this paper shows that each part of the PDC bit (bit profile, active and passive gages) plays a major role on the walking tendency and steerability of the bit. A quantitative evaluation of the contribution of these factors on the well trajectory (inclination and azimuth) is given. A full-scale directional drilling bench was built to measure, for the first time, the walking tendency and the steerability of PDC bits. The results obtained demonstrate that the bit profile, the gage cutters and the gage length have a significant effect on the walking tendency and on the steerability of the PDC bits. A 3D theoretical rock-bit interaction model was developed to reproduce the drilling tests results.

We measured the spectral reflectance of the fovea of ten normal subjects in four conditions, i.e. under dark-adapted and bleached conditions and at two retinal angles of incidence. The objective was to study optical pathways through the photoreceptor layer, resulting in a model that simultaneously explains spectral, directional and bleaching properties of the fovea. On theoretical grounds, we propose that small reflections from the stack of discs in the cone outer segments are the origin of the directional component of foveal reflection. Non-directional reflection occurs at the inner limiting membrane and at all layers posterior to the outer segments. With four reflectance spectra as input, the model allows determination of the density of the photostable absorbers, the lens, macular pigment, melanin and blood. Because of the simplified modeling of the layers posterior to the photoreceptor layer, the values for the density of melanin and blood are not necessarily comparable to physiological data. The density of the visual pigment calculated with this model is consistent with psychophysical data, with estimates for the ten subjects ranging from 0.41 to 0.80. The long wavelength sensitive cone fraction is calculated as 0.56. Copyright © 1996 1996 Elsevier Science Ltd.

Background Influenza H5N1 is one subtype of the influenza A virus which can infect human bodies and lead to death. Timely diagnosis before its breakout is vital to the human health. The current clinical biochemical diagnosis for influenza virus are still flawed, and the diagnostic kits of H5N1 are mainly based on traditional monoclonal antibodies that hardly meet the requirements for clinical applications. Nanobody is a promising tool for diagnostics and treatment due to its smallest size, high specificity and stability. In this study, a novel Nanobody-based bioassay was developed for rapid, low-cost and sensitive detection of the influenza H5N1 virus. Methods Nanobodies specific to H5N1 virus were selected from a VHH library by phage display technology. In this system, the biotinylated Nanobody was directionally captured by streptavidin coated on ELISA plate, which can specifically capture the H5N1 virus. Another Nanobody conjugated with HRP was used as a detector. A novel directional enzyme-linked immunosorbent assay for H5N1 using specific Nanobodies was established and compared to the conventional undirected ELISA assay. Results We have successfully constructed a high quality phage display Nanobody library and isolated two Nanobodies against H5N1 with high affinity and specificity. These two Nanobodies were further used to prepare the biosensor detection system. This streptavidin-biotin-based directional double Nanobodies sandwich ELISA for H5N1 detection showed superiority over the commonly undirectional ELISA protocol. The linear range of detection for standards in this immunoassay was approximately 50–1000 ng/mL and the detection limit was 14.1 ng/mL. The average recoveries of H5N1 virus from human serum samples were in the range from 94.58% to 114.51%, with a coefficient of variation less than 6.5%. Conclusion Collectively, these results demonstrated that the proposed detection system is an alternative diagnostic tool that enables a rapid, inexpensive, sensitive and specific detection of the influenza virus.

Recent developments in PDC bit modelling and single cutter analysis have enabled to design a new generation of cutting structures – based on the optimization of a specific interactive cutting mode – that generates, by the mere drilling action of the cutters, an axial force oriented in the drilling direction: a negative weight on bit. This paper presents the application of this new PDC bit design and shows that WOB can be significantly reduced in a wide range of formations. A monobloc 8″1/2 PDC bit was designed, tested in laboratory, and self penetration was clearly achieved in field conditions. A full PDC bit design methodology using a new PDC cutters geometry optimized for a maximum thrust effect, along with specific manufacturing procedures for high-level precision in cutter positioning, were developed for this specific new bit generation. Laboratory tests showed that it was possible to drill without WOB at a high rate of penetration and with a small increase in specific energy. Preliminary field tests in cement demonstrated that self penetration – drilling with the neutral point just above the bit – was possible with specific surface control, and a first operational application was conducted by Total E&P Angola. This new bit technology has the potential to increase bit performance, specifically in operating conditions where power is available but WOB is limited due to friction, buckling or reduced vertical depth. The ability to drill with reduced WOB – or even without any WOB – should extend the potential of existing drilling technologies such as Extended Reach Drilling, Coiled Tubing or Steerable Motor in sliding mode and reduce axial vibration, thus increasing the MTBF of downhole tools.