nils-herrmann/clean_scirepeval huggingface dataset:
Towards freely and correctly adjusted Dijkstra's algorithm with semantic decision tables for ontology based data matching

Researches on ontology based data matching have been recently explored. In this paper, we will focus on how to adapt Dijkstra's algorithm for matching two data sets and how to freely adjust the parameters of Dijkstra's algorithm by the end users. A novel approach of using semantic decision tables for the adjustment will be presented and discussed. This particular approach provides a generic, user friendly, simple yet powerful solution to control an algorithm in an elegant way. In order to present the matching result, we propose a formula called GRASIM, which uses the travel cost of the shortest path, to calculate the similarities between two data sets.
A tree-based statistical language model for natural language speech recognition

The problem of predicting the next word a speaker will say, given the words already spoken; is discussed. Specifically, the problem is to estimate the probability that a given word will be the next word uttered. Algorithms are presented for automatically constructing a binary decision tree designed to estimate these probabilities. At each node of the tree there is a yes/no question relating to the words already spoken, and at each leaf there is a probability distribution over the allowable vocabulary. Ideally, these nodal questions can take the form of arbitrarily complex Boolean expressions, but computationally cheaper alternatives are also discussed. Some results obtained on a 5000-word vocabulary with a tree designed to predict the next word spoken from the preceding 20 words are included. The tree is compared to an equivalent trigram model and shown to be superior.
Two advanced solar antenna "SOLANT" designs for satellite and terrestrial communications

A novel hybrid technology where amorphous silicon (a-Si:H) solar cells are either integrated or physically combined with printed slot antennas is presented. This basic idea is demonstrated with the help of two innovative designs where the solar cells are directly grown on a stainless steel ground-plane or glued onto a standard copper layer printed on a dielectric substrate. To show the compatibility of solar cells and antennas, the concept is used to create a linearly polarized slot antenna, a circularly polarized slot antenna and a slot array. The concept offers advantages in terms of surface coverage, volume, weight and electric performance when compared with a simple juxtaposition of antennas and solar cells.
TE Surface Wave Resonances on High-Impedance Surface Based Antennas: Analysis and Modeling

Low-profile antennas comprising a horizontal dipole above a high-impedance surface are analyzed. The emphasis of this paper is on the additional resonances of the radiating structure caused by surface waves propagating on the high-impedance surface. It is shown that such resonances can be favorably used for broadening the bandwidth of the antenna. The phenomenon is thoroughly modeled by exploiting a parallel between the HIS structure and a waveguide resonator. In the second part of the paper we discuss homogenized approaches for modeling the radiating properties of the antenna with emphasis to the phenomenon discussed in the first part. As it turns out, it is necessary to take into account the spatially dispersive properties of high-impedance surfaces, and most of the simplified models commonly used for analyzing high-impedance surface based antennas fail in predicting the discussed resonance mode.
Improved lossless halftone image coding using a fast adaptive context template selection scheme

Applications such as printing on demand and personalized printing have arisen where lossless halftone image compression can be useful for increasing transmission speed and lowering storage costs. We present an improvement on the context modeling scheme by adapting the context template to the periodic structure of the halftone image. This is a non-trivial problem for which we propose a fast close-to-optimal context template selection scheme based on the calculation and sorting of the autocorrelation function on a part of the image. For evaluating our scheme, we have also investigated the compression performance of a suboptimal approach based on an incremental exhaustive search; this approach can be used in practice for decompression but not for compression because of timing requirements. We have experimented with classical halftones of different resolutions and sizes and screened under different angles.
Low Profile GALILEO Antenna Using EBG Technology

A dedicated low profile antenna for geodesic applications is presented. This type of antenna requires mitigation of multipath signals to achieve sub-centimeter level of precision. Typically, bulky and heavy choke ring structures have been used to reduce the effects of multipath interference. The antenna presented here consists of a low temperature co-fired ceramic (LTCC) patch antenna immersed in an electromagnetic bandgap (EBG) substrate. The EBG substrate reduces the effects of multipath by blocking the propagation of surface waves. The result is an antenna showing good multipath rejection and a stable phase center. The advantage of printed EBG substrates is that they can be realized in a low-weight, low-price, and low-profile fashion. First prototypes have been manufactured and tested, and its performance has been compared to that of a more classical choke ring antenna.
A low power consumption driver with low acoustics for piezoelectric synthetic jets

The low profile piezoelectric synthetic jet is a promising approach for forced air convection cooling of electronics for high density and portable applications. The synthetic jet considered in this paper, known as a DCJ (), consists of a pair of piezoelectric discs mounted on a frame and driven with a voltage, which causes the discs to mimic the action of a pair of bellows. This DCJ requires a sinusoidal waveform of 125-175 Hz at an amplitude up to bQV, and must operate from a 5V DC source. The mostly capacitive load of the DCJ presents a challenge for typical amplifiers. Furthermore, many applications require quiet operation; hence the jet driving waveform must have very low distortion to prevent audible acoustic noise. This paper describes a bidirectional power driver topology for driving capacitive loads based on a dual flyback topology, along with a low-cost, pure sine reference generator with predistortion to allow a clean output waveform without feedback. The driver achieves low power consumption (rì 250mW) with low harmonic content. The use of predistortion and a delta-sigma DAC compensates for the inherent flyback converter nonlinearity and the low resolution DAC typical of low-cost microcontrollers. The paper describes and presents experimental results for a design that accomplishes these objectives in a 30 mm × 30 mm × 4 mm volume.
Block-based detection systems for visual artifact location

The core of many video coding standards is formed by the Discrete Cosine Transform (DCT) for de-correlating spatial video data. When quantizing DCT sub-bands, artifacts may appear such as mosquito noise and ringing. Spatial artifact reduction requires artifact location information, to control the filter process, thereby avoiding unnecessary blurring of artifact-free regions. This location information can be derived, either in the time- or frequency domain. As coding artifacts are most annoying in flat or low-frequency regions, the objective of the detector is to localize these artifact-sensitive locations. The detection accuracy, coverage and sensitivity differ between the two possible detection domains. The time-domain solution has a 10-97% location detection performance, whereas the frequency domain results in 70-100% detection performance.
A Combined 380 GHz Mixer/Doubler Circuit Based on Planar Schottky Diodes

The design, fabrication and test of a combined sub-millimeter wave mixer/doubler featuring a 380 GHz sub-harmonic mixer and a 190 GHz frequency doubler on a single quartz based microstrip circuit is reported in this letter. The integrated circuit uses separate flip-chip mounted planar Schottky diode components to perform the two functions. Measurements give best double sideband mixer noise temperatures of 1625 K at 372 GHz, and a corresponding mixer conversion loss of 8 dB. The measured fixed-tuned radio frequency bandwidth extends from 368 to 392 GHz, in good agreement with simulations. This work represents the first demonstration of a single substrate combined submillimeter wave mixer/doubler.
Low-frequency noise as a diagnostic tool for OLED reliability

Organic light emitting diodes (OLED), either based on polymers or small molecules, suffer from early failure: an unpredictable sudden increase in current with a total loss of light output. This work addresses this problem using small-signal impedance measurements and electrical noise techniques. Robust OLEDs show a current noise spectrum proportional to 1/f. OLEDs susceptible to failure have 1/f3/2 and/or may start exhibiting a standard 1/f behavior that rapidly evolves with time (typical 30 minutes) to 1/f1.6. In addition OLEDs susceptible to early failure have a higher DC leakage. It is proposed that a combination of both measurements can be used as a diagnostic tool for OLED reliability in a production line. Insight into the physics of the degradation mechanism is also provided. Unreliable OLEDs exhibit current switching events and optical blinks at wavelengths higher than the polymer band gap electroluminescence. It is proposed that degradation is induced by the appearance of an insulating resistive switching layer. Charge recombination trough this layer is responsible for the optical and electrical blinks.
100-Gbps RZ Data Reception in 67-GHz Si-Contacted Germanium Waveguide p-i-n Photodetectors

We demonstrate 100-Gbps silicon-contacted germanium waveguide p-i-n photodetectors integrated on imec's silicon photonics platform. The performance of 14 and 20 μm long devices is compared. The responsivity of the devices is 0.74 and 0.92 A/W at 1550 nm, respectively.
EBG Superstrate for Gain Enhancement of a Circularly Polarized Patch Antenna

EBG enhanced antennas could advantageously replace conventional array antenna in Geo-synchronous global Earth coverage applications at S-band and lower frequencies. This new technology simplifies the antenna configuration and can potentially lead to lighter and cost effective solutions, by either eliminating or strongly simplifying the antenna beam forming network (BFN). Excellent agreement between the predictions and the measurements has been shown
22.5 A 4×20Gb/s WDM ring-based hybrid CMOS silicon photonics transceiver

Silicon photonics (SiPh) has been identified as a prime technology targeting cost-effective short-range optical links . Wavelength-division multiplexing (WDM) is an attractive approach for enabling high aggregate transceiver bandwidth without increasing the number of optical fibers used in the link. Ring-based optical modulators and wavelength-selective filters are attractive devices for scalable WDM SiPh transceivers owing to their compact footprint and moderate power required for thermal tuning. In this paper, we report on a thermally controlled ring-based flip-chip integrated CMOS-SiPh transceiver with 4 channels operating at 20Gb/s.
System Design of Advanced Video Navigation Reinforced with Audible Sound in Personal Video Recording

This paper presents an advanced video navigation concept based on a picture in picture (PiP) allowing combined rendering of fragments of normal-play video and fast search video simultaneously. Loss of audio during conventional fast search trick-play is eliminated, by adding the sound of the normal play fragment. The normal-play fragments provide detailed information, whereas the fast-search signal presents a course overview. The audio associated to the normal-play fragments enhances the navigation process, allowing the viewer to concentrate on either the normal play or the fast search window. Efficient signal processing in the MPEG-2 domain permits re-use of the standard MPEG-2 decoding path for decoding the normal play audiovisual fragments. Applying a scalable MPEG-2 decoder for decoding the fast search signal enables a low-cost implementation for personal video recording (PVR).
On the Relevance of the Modularity Concept for Understanding Outsourcing Risk Factors

Contemporary organizations frequently seek external and specialized partners to outsource some of their non-core, though highly complex tasks, including their information systems. In literature, a variety of outsourcing risk factors which lead to unsuccessful project outcomes have been identified. Despite many remedies suggested by practitioners and scholars to mitigate these risk factors, empirical studies continue to report frequent failures in outsourcing projects. This paper suggests an alternative perspective to analyze risks related to outsourcing projects, based on the concept of modularity. Such a new perspective can help in complementing existing outsourcing risk analyses with new or deeper insights as a basis to define a more exhaustive list of required mitigating actions, which in turn could lead to more succesful outsourcing projects. To illustrate this alternative perspective, a reanalysis of a failed outsourcing case is discussed. The paper shows in a detailed way how poorly designed modular structures at the technical and project level could have been identified ex-ante. This identification may explain the manifestation of ex-post outsourcing risk factors such as 'lack of required skills', 'managing user expectation' and 'communication problems'.
Reconfigurable electromagnetic band gap based structures with defects for MM wave and antenna applications

There has been increasing interest in the field of electromagnetic band gap (EBG) materials . This is due to the fact that EBG structures have unique frequency selective properties and vast number of applications in microwave, millimeter wave and optical devices. This paper presents a study of a tunable planar EBG based structure with defects introduced in specific areas. The defects considered are in form of element discontinuities and varying element dimensions. The circuit has been realised by placing a transmission line across a periodic array of dipoles on grounded dielectric substrate. The photoconductive properties of silicon are utilised to alter the dimensions of the elements resulting in the reconfigurable stopband. The ability to adaptively control the circuit by switching on and off the element defects using optical illumination has been the predominant factor influencing the choice of the design. We have obtained both predicted and measured results up to 20 GHz for the performance and behaviour of the EBG structures. Overall, the agreement between the measured and the predicted results have been good.
Reliability Oriented Design Tool For the New Generation of Grid Connected PV-Inverters

This paper introduces a reliability-oriented design tool for a new generation of grid-connected photovoltaic (PV) inverters. The proposed design tool consists of a real field mission profile (RFMP) model (for two operating regions: USA and Denmark), a PV panel model, a grid-connected PV inverter model, an electrothermal model, and the lifetime model of the power semiconductor devices. An accurate long-term simulation model able to consider the one-year RFMP (solar irradiance and ambient temperature) is developed. Thus, the one-year estimation of the converter device thermal loading distribution is achieved and is further used as an input to the lifetime model. The proposed reliability-oriented design tool is used to study the impact of mission profile (MP) variation and device degradation (aging) in the PV inverter lifetime. The obtained results indicate that the MP of the field where the PV inverter is operating has an important impact (up to 70%) on the converter lifetime expectation, and it should be considered in the design stage to better optimize the converter design margin. In order to have correct lifetime estimation, it is crucial to consider also the device degradation feedback (in the simulation model), which has an impact of 20-30% on the precision of the lifetime estimation for the studied case.
Hybrid compression of video with graphics in DTV communication systems

Advanced broadcast manipulation of TV sequences and enhanced user interfaces for TV systems have resulted in an increased amount of pre- and post-editing of video sequences, where graphical information is inserted. However, in the current broadcasting chain, there are no provisions for enabling an efficient transmission/storage of these mixed video and graphics signals and, at this emerging stage of DTV systems, introducing new standards is not desired. Nevertheless, in the professional video communication chain between content provider and broadcaster and locally, in the DTV receiver, proprietary video-graphics compression schemes can be used to enable more efficient transmission/storage of mixed video and graphics signals. For example, in the DTV receiver case this will lead to a significant memory-cost reduction. To preserve a high overall image quality, the video and graphics data require independent coding systems, matched with their specific visual and statistical properties. We introduce various efficient algorithms that support both the lossless (contour, runlength and arithmetic coding) and the lossy (block predictive coding) compression of graphics data. If the graphics data are a-priori mixed with video and the graphics position is unknown at compression time, an accurate detection mechanism is applied to distinguish the two signals, such that independent coding algorithms can be employed for each data-type. In the DTV memory-reduction scenario, an overall bit-rate control completes the system, ensuring a fixed compression factor of 2-3 per frame without sacrificing the quality of the graphics.
An MPEG Decoder with Embedded Compression for Memory Reduction

We present an MPEG decoder with reduced system costs by employing embedded compression of the reference frames which are used for motion compensated (MC) decoding. The embedded compression scheme used is based on either block predictive coding or DCT transform coding, depending on the required memory compression. The compression features simple recovery of (MC) block data, while preventing visible artifacts. The compression was optimized for low costs, enabling real application in a commercial MPEG IC. It was found that the same techniques can be applied in the encoder as well.
Mixed service management with QoS control for GERAN - the GSM/EDGE radio access network

This paper describes and evaluates service-based power setting for the GSM/EDGE Radio Access Network (GERAN). Service-based power setting is a simple radio resource management scheme that allows management of multiple services with controlled quality of service (QoS), which is crucial for 3/sup rd/ generation systems. Simulation results indicate that with proper power offsets between bearer services previously established single service capacities may be maintained also for a mix of different services. It is further shown that the power setting principles work well in combination with power control.
Streaming services in GSM/EDGE-radio resource management concepts and system performance

Managing multiple services with controlled quality of service (QoS) is crucial to 3/sup rd/ generation cellular system. The real time services, i.e. the traffic classes streaming and conversational, will be the most costly services and therefore most crucial to manage in a spectral efficient manner. This paper proposes and evaluates possible ways to accomplish this for the GSM/EDGE Radio Access Network (GERAN). The evaluation is made with different mixes of voice, WWW browsing and video streaming services, where the latter is based on a novel traffic model for a streaming service using an H.263 codec with suitable settings. The results from the dynamic multiple-cell system simulations show that it is possible to efficiently manage streaming services in GERAN, in single as well as mixed service scenarios, by using service based radio resource management algorithms, e.g., power setting.
Automating Vector Autoregression on Electronic Patient Diary Data

Finding the best vector autoregression model for any dataset, medical or otherwise, is a process that, to this day, is frequently performed manually in an iterative manner requiring a statistical expertize and time. Very few software solutions for automating this process exist, and they still require statistical expertize to operate. We propose a new application called Autovar, for the automation of finding vector autoregression models for time series data. The approach closely resembles the way in which experts work manually. Our proposal offers improvements over the manual approach by leveraging computing power, e.g., by considering multiple alternatives instead of choosing just one. In this paper, we describe the design and implementation of Autovar, we compare its performance against experts working manually, and we compare its features to those of the most used commercial solution available today. The main contribution of Autovar is to show that vector autoregression on a large scale is feasible. We show that an exhaustive approach for model selection can be relatively safe to use. This study forms an important step toward making adaptive, personalized treatment available and affordable for all branches of healthcare.
Pitfalls when correlating TLP, HBM and MM testing

Correlation between human body model (HBM), machine model (MM) and transmission line pulse (TLP) testing is still under discussion. In this paper, it is shown that the lack of correlation is due to misinterpretations in the test results, due to the fact that soft and hard failures are often confused. This is illustrated by ESD results of test structures with grounded-gate NMOSTs and field oxide devices, measured according to HBM, MM and by means of TLP testing. It is shown that for a valid comparison, it is essential to combine electrical measurements with a thorough physical failure analysis in order to establish the failure signature. Once the failure signature and the current path are taken into account, a good correlation is found.
System requirements and considerations for visual table of contents in personal video recording

With the introduction of non-tape based digital video recorders, consumers can expect alternative navigation methods to the well-known trick-play modes found on analog and digital tape-based systems. In this paper, we explore the system requirements and aspects of the Visual Table of Content (VTOC). One reason for implementing a VTOC search mode is that it provides a much higher visual performance at high search speeds (50 times or higher) than the conventional search techniques. We present a solution based on re-using MPEG-compressed video data to generate the video signal for the visual search. The video search signal is composed of a set of sub-pictures (mosaic screen) each of which is MPEG compressed An efficient strategy is introduced that allows either full or partial re-use of the compressed sub-pictures to allow the generation of a new mosaic screen.
Measurement of the dielectric constant and loss tangent of high dielectric-constant materials at terahertz frequencies

Low-loss high dielectric-constant materials are analyzed in the terahertz frequency range using time-domain spectroscopy. The dielectric constant and loss tangent for steatite, alumina, titania loaded polystyrene, and zirconium-tin-titanate are presented and compared to measurements on high-resistivity silicon. For these materials, the real part of the dielectric constant ranges from 6 to 90. All of the samples were found to have reasonable low-loss tangents. Applications as photonic crystal substrates for terahertz frequency antenna are envisaged.