bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reliability of Outcome Measures to Assess Consonant Proficiency Following Cleft Palate Speech Intervention: The Percentage of Consonants Correct Metric and the Probe Scoring System
Authors: Alighieri Cassandra , Bettens Kim , Bruneel Laura , D'haeseleer Evelien , Van Gaever Ellen , Van Lierde Kristiane 
Published: May 2021

PurposeThis study compared the inter- and intrarater reliability of the percentage of consonants correct (PCC) metrics and the probe scoring system between an experienced and a less experienced rater and between two experienced raters. In addition, these outcome measures' ability to reflect changes following speech intervention was measured.MethodDuring Phase 1, two raters (Rater 1 with 5 years of experience in cleft-related speech disorders and Rater 2 with limited experience in cleft-related speech disorders) independently assessed 134 speech samples at the word and sentence levels, which were collected on different data points before, during, and following a cleft palate speech intervention. During Phase 2, a third rater (with 8 years of experience) analyzed 34 speech samples. The percentage of consonants correct–revised, the percentage of correct places and manners, and probe scores at the word and sentence levels were measured.ResultsPoor-to-moderate interreliability between Raters 1 and 2 was found due to differences in error classification. Interrater reliability between Raters 1 and 3 was very good for both the PCC metrics and the probe scores. The interrater reliability for the amount of targets elicited was lower compared to the interrater reliability for the amount of targets correct. The probe scoring system demonstrated a greater ability to detect changes toward the correct production of the target consonant compared to the PCC metrics.ConclusionsHaving an experience with the assessment of cleft-related speech disorders is a crucial factor to gain reliable results. The interrater reliability for the PCC metrics and the probe scoring system between two experienced raters did not differ, suggesting that both outcome measures can be used in cleft palate speech intervention studies. Despite the ability of the probe scoring system to detect changes, further research should provide insight in the benefits of this system both for research and clinical purposes.
Spatial and temporal modelling of coupled power and transportation systems: A comprehensive review
Authors: Sun Yingyun , Zhao Pengfei , Wang Liwei , Malik Sarmad Majeed 
Published: May 2021

AbstractThe large‐scale application of electric vehicles can lead to new challenges in the operation of the two complex and coupled networks of electricity and transportation systems, thus creating a new concept—a power—traffic network. The purpose is to provide a comprehensive survey of this emerging field. First, both the transportation system and power grid models are briefly introduced in terms of time and space scales. Then, the power traffic network model and applications at long‐term, mid‐term, and short‐term time scales are summarized, and provided a unified view of these achievements. Based on this analysis, recommendations for future research are presented.
Swarm‐based mean‐variance mapping optimization for optimal placement of energy storage with synthetic inertia control on a low inertia power grid
Authors: Rahman Fathin Saifur , Israjuddin  , Hariyanto Nanang , Liu Chih‐Wen 
Published: May 2021

AbstractUtilizing energy storage systems equipped with virtual/synthetic inertia control has emerged as one of the solutions to solve low inertia issues in power systems with massive penetration of renewables. However, while the aspect regarding the control of the synthetic inertia control has been widely investigated, the optimal placement of synthetic inertia control is rarely investigated. Therefore, the optimal placement of energy storage system with synthetic inertia control based on swarm‐based mean‐variance mapping optimization is proposed. The performance of the proposed method is tested by considering several cases, both single and multiple contingencies. By utilizing the proposed method, the optimal placement of energy storage system equipped with synthetic inertia control could be obtained, in which the resulting frequency response is better compared to randomly placed ones. The proposed method could also be applied by considering multiple contingencies in different locations. Furthermore, the resulting fitness values for different independent optimization repetitions for various study cases are consistent, leading to the efficacy to be applied in the actual power system planning.
Part‐MOT: A multi‐object tracking method with instance part‐based embedding
Authors: Liu Xiaohu , Luo Yichuang , Yan Keding , Chen Jianfei , Lei Zhiyong 
Published: May 2021

AbstractPart‐MOT, a one‐stage anchor‐free architecture which unifies the object identification representation and detection in one task for visual object tracking is presented. For object representation, a position relevant feature is obtained using the center‐ness information, which takes advantage of the anchor‐free ideal to encode the feature map as the instance‐aware embedding. To adapt to the object's movement, the clustering‐based method to get the global instance feature is introduced. This enables this approach more robust to make better tracking decisions. Part‐MOT achieves the state‐of‐the‐art performance on public datasets, with especially strong results for object deformation and movement changes.
A discriminative self‐attention cycle GAN for face super‐resolution and recognition
Authors: Li Xiaoguang , Dong Ning , Huang Jianglu , Zhuo Li , Li Jiafeng 
Published: May 2021

AbstractFace image captured via surveillance videos in an open environment is usually of low quality, which seriously affects the visual quality and recognition accuracy. Most image super‐resolution methods adopt paired high‐quality and its interpolated low‐resolution version to train the super‐resolution network. It is difficult to achieve contented visual quality and restoring discriminative features in real scenarios. A discriminative self‐attention cycle generative adversarial network is proposed for real‐world face image super‐resolution. Based on the cycle GAN framework, unpaired samples are adopted to train a degradation network and a reconstruction network simultaneously. A self‐attention mechanism is employed to capture the contextual information for details restoring. A Siamese face recognition network is introduced to provide a constraint on identify consistency. In addition, an asymmetric perceptual loss is introduced to handle the imbalance between the degradation model and the reconstruction model. Experimental results show that the observation model achieved more realistic low‐quality face images, and the super‐resolved face images have shown better subjective quality and higher face recognition performance.
Analysis of a direct‐drive permanent magnet synchronous generator with novel toroidal winding
Authors: Wei Yanqi , Cheng Zhiping , Si Jikai , Jin Fuli , Gao Caixia , Gan Chun 
Published: May 2021

AbstractDirect‐drive permanent magnet synchronous generators (DDPMSGs) are gaining more and more attention in the field of wind power because of the advantages of simple structure, high efficiency and high reliability. However, due to the extremely low rotational speed, large volume and heavy weight of DDPMSGs, it poses serious challenges for transportation and installation, which limits its application. Therefore, a DDPMSG with novel toroidal windings (NTW) is proposed to improve power density in this paper. Unlike regular windings, each coil of the NTWs is wound onto the stator yoke in the same direction. The special configuration enables the generator to have higher winding coefficient, so that the DDPMSG with NTWs (NTW‐DDPMSG) can achieve higher power density than traditional fractional slot concentrated windings (FCW). The proposed topology and operating principles are described in detail. To verify the merits of the proposed NTW‐DDPMSG, the electromagnetic parameters of two external rotor surface‐mounted DDPMSGs equipped with NTW and FCW respectively are designed. The characteristics of air‐gap magnetic field, no‐load electromotive force, output power, loss and efficiency are analysed on the conditions of different loads and speeds. Comparison results show that the proposed NTW‐DDPMSG has higher power density than FCW‐DDPMSG.
Performance investigation and parametric optimization of an eco‐friendly sustainable design solar air heater
Authors: Goel Abhishek Kumar , Singh Shailendra Narayan , Prasad B.N 
Published: May 2021

AbstractThe impacting air jet type collector equipped with fins underneath the absorber surface has been investigated experimentally. Real outdoor conditions were preferred for a specific range of operational parameters (mentioned in Table 1). The experimental investigation covers the analysis of temperature rise parameter (TRP) and instantaneous collector thermal efficiency. The thermal enhancement and other performance characteristics as a result of combining both (impacting air jet mechanism and fins) methods have been studied in detail. It has been observed that TRP decreases and collector efficiency increases with an increase in flow rate. The influence of variable duct aspect ratio has been examined as a function of relevant geometrical parameters of the duct. In the time span of 12.00 hrs–01.00 pm maximum rise in air temperature has been reported at different fin parameters. In conjunction with jet and fin parameters, a parametric optimization model is discussed which yields the optimum values of design parameters to attain maximum efficiency. The experimental and analytical results are validated with similar works. The comparative analysis reports a mean deviation of ±12.7% in TRP and ±7.8% in collector efficiency at w/Dh = 0.23, Dj/Dh = 0.076. The optimum values will be of great help for the researchers and designers exploring this area.
Optimal investment and operation of a microgrid to provide electricity and heat
Authors: Angarita Jorge L , Jafari Hossein , Mohseni Mojtaba , Al‐Sumaiti Ameena Saad , Heydarian‐Forushani Ehsan , Kumar Rajesh 
Published: May 2021

AbstractThis paper proposes a robust investment and operation model to attend the power and heat needs of a microgrid (MG) connected to the distribution system. The optimization algorithm decides on the best investment and operation of combined heat and power (CHP), boilers, PV power generation and battery energy storage systems (BESS). For the BESS, the algorithm estimates the optimal energy storage capacity (MWh) as well as the maximum hourly delivery capacity (MW). The non‐linear and non‐concave heat rate chart is recast by a mix‐integer linear model to have a tractable and precise model. The model considers the uncertain in some parameters using probability density function (pdf) to portrait its behavior. Thus, the problem has been modeled using stochastic programming approach, and its objective function is the expected value of the annual operational cost. The model is tested using a real case where two adjacent consumers share the power and heat facilities to minimize the overall up to 17% depending on the gas price scenario. The results demonstrate the benefits of employing different technologies and the synergies of all technologies operating together.
Method for functional state recognition of multifunction radars based on recurrent neural networks
Authors: Xu Xinsong , Bi Daping , Pan Jifei 
Published: May 2021

AbstractRadar signal recognition plays a vital role in electronic warfare. For the multifunction radars (MFRs) with complex dynamical modes, the signal recognition needs to identify not only the emitter but also its current functional state. Existing research on MFR recognition mainly focuses on hierarchical modelling approaches. Inspired by recent progress of deep neural networks, the authors propose to further develop radar signal modelling with recurrent neural networks. Here, the authors propose a more efficient method for functional state recognition of MFRs based on a gated recurrent unit (GRU). The method makes full use of the ability of GRUs to automatically learn the characteristics of radar signal sequences, and the nonlinear modelling of GRUs can deal with the corrupted data well. Simulation results on the Mercury radar show that the proposed method achieves a great recognition accuracy with little prior information, and the designed GRU model outperforms the predictive state representation model under the same condition.
Real‐time capable multiple‐input–multiple‐output SONAR systems—An algorithmic approach
Authors: Kaak Thorben , Abshagen Jan , Schmidt Gerhard 
Published: May 2021

AbstractIn recent years, significant effort has been allocated to research on multiple‐input–multiple‐output (MIMO) sound navigation and ranging (SONAR) and RADAR systems. Most work has been conducted on the general theoretical functionality of such systems. Less effort has been applied to considerations of the real‐time MIMO capability, although this is an important factor for the application of these new algorithms in real SONAR systems. To account for this, the following work focusses, after introducing the used methodology and revisiting the general MIMO idea and considered system, on more effective permutations of the involved algorithms in the reduction of floating‐point operations. In this context, the general necessity of the algorithms utilized is shown. Furthermore, it is proven that the reduction in computational load does not affect the performance of the system. In addition, the main algorithmic parts of MIMO systems can be exchanged almost arbitrarily under given restrictions without changing the result. Therefore, the performance differences in floating‐point operations are depicted to give an estimate of the achievable degree of complexity reduction. The results for the investigated systems and algorithms are obtained by applying a system simulation of a simple underwater channel. The obtained results were also verified using a real MIMO SONAR system operating in real time.
Low‐slow‐small target detection using stepped‐frequency signals in a strong folded clutter environment
Authors: Guo Jinpeng , Chang Shaoqiang , Yang Fawei , Cai Jinjian , Liu Quanhua , Long Teng 
Published: May 2021

AbstractThe popularisation of unmanned aerial vehicles (UAVs) and the security threats that follow have made the detection of low‐slow‐small (LSS) targets a hotspot in the radar field. For ground‐based surveillance radars (GSR), the folded‐clutter is an important factor affecting LSS target detection performance. Herein, the stepped‐frequency (SF) signal is used to improve the performance of the folded‐clutter suppression and the LSS target detection for the GSR. Furthermore, an optimisation method for the SF signal parameter design is proposed to maximise the folded‐clutter improvement factor. Specifically, signal parameters including the frequency step number and the step sequence are optimised based on the clutter cognition results. To verify the effectiveness of the well‐designed SF signals in the LSS target detection, simulation experiments and field tests using an L‐band SF‐GSR and a DJI M600‐Pro UAV are conducted. Compared to the results achieved by a simple chirp signal, the detection probabilities of the LSS target with different velocities are significantly increased when the SF signals are used in a typical strong folded‐clutter background.
Non‐stationary clutter suppression method for bistatic airborne radar based on adaptive segmentation and space–time compensation
Authors: Xiong Yuanyi , Xie Wenchong 
Published: May 2021

AbstractBistatic airborne radar has excellent performance due to the separate transmitter and receiver, but its clutter distribution is usually non‐stationary, which causes the performance of the traditional Space time adaptive processing (STAP) method to fail. Herein, firstly a bistatic airborne radar clutter signal model established, followed by an analysis of its clutter distribution characteristics in detail, and finally a bistatic airborne radar space–time compensation STAP method based on adaptive segmentation is proposed. The method first uses the distribution characteristics of the peak spectral centre in the first pulse data of the airborne radar to adaptively segment the clutter data, including extremely non‐stationary, severely non‐stationary, and non‐stationary clutter regions. Then the clutter data are compensated based on the estimation value of the space–time peak spectrum centre. Finally, each range section is processed by using STAP, and the detected target Doppler frequency is adaptively moved. Simulation results verify the effectiveness of the proposed method.
Empirically revealed properties of Rieger-type cycles of stellar activity
Authors: Arkhypov O. V. , Khodachenko M. L. 
Published: May 2021

Context. The Rieger cycles were discovered in the Sun as a specific 154-day periodicity of flare occurrence; they strongly influence terrestrial space weather. This phenomenon is far from being understood. Various proposed mechanisms for this periodicity need further verification in stars with stellar parameters different from those of the Sun.
Aims. In this work, we study the Rieger-type cycle (RTC) periods PRTC of stellar activity surveyed in the photometric data of the Kepler space telescope.
Methods. The processing of 1726 stellar light curves reveals statistics of PRTC values for different main-sequence stars with different effective temperatures Teff and periods of rotation P. This study uses as an index of stellar activity the squared amplitude of the first rotational harmonic A12 of the stellar light curve variability.
Results. The obtained information on PRTC of the considered stars confirms the phenomenological analogy between stellar RTCs and the solar Rieger cycles. Two types of RTCs were found: (1) activity cycles with PRTC independent on the stellar rotation, which are typical for the stars with Teff ≲ 5500 K, and (2) activity cycles with PRTC proportional to the stellar rotation period P, which take place on stars with Teff ≳ 6300 K. These two types of RTCs can be driven by the Kelvin and Rossby waves, respectively. The Rossby wave-driven RTCs show a relation with the location of tachocline at shallow depths in the hot stars. This confirms the theoretical predictions of the connection of the RTC with the tachocline. At the same time, the Kelvin wave-driven RTCs do not show this connection. Apparently, both types of wave drivers of RTCs can coexist, resulting in the joint modulation of the magnetic flux tubes emergence by Kelvin and Rossby waves, and the corresponding behavior of PRTC.
Conclusions. The signatures of two types of wave drivers discovered for RTCs and their different relations with the tachocline call for a revision and further elaboration of the theory of RTCs.
Catalytic Enantioselective Synthesis of Silicon-Stereogenic Alkoxy­silanes and Siloxanes
Authors: He Chuan , Zhu Jiefeng 
Published: May 2021

AbstractA Rh-catalyzed enantioselective intermolecular dehydrogenative Si–O coupling of dihydrosilanes with alcohols and silanols is demonstrated. Rh(I) catalyst equipped with a Josiphos ligand enables the highly enantioselective alcoholysis process of dihydrosilanes, giving access to a variety of functionalized triorgano-substituted silicon-stereogenic alkoxysilanes and siloxanes in decent yields and ee, which significantly expand the chemical space of the silicon-centered chiral molecules. Utility of this methodology is illustrated by the construction of circularly polarized luminescence (CPL) active chiral alkoxysilane small organic molecules.1	Introduction2	Conditions Optimization3	Substrate Scope4	Application5	Conclusions6	Experimental Procedure
Lewis Acid Mediated [3+2] and [3+3] Annulations of an Azomethine Imine with Donor–Acceptor Cyclopropanes
Authors: Sikervar Vikas , Sonawane Ravindra , Mandadapu Raghuramaiah , Dehade Amol Satish , Shete Shrikant Abhiman , Montgomery Mark 
Published: May 2021

AbstractTwo different Lewis acids were used for developing [3+2] and [3+3] regioselective cycloaddition reactions of an azomethine imine with activated cyclopropanes. Scandium(III) triflate catalyzes a [3+2] cycloaddition reaction of the azomethine imine with cyclopropanes to form tetrahydropyrazolone derivatives and tricyclic tetrahydrofuran derivatives in moderate yields. Complementary to this, a novel [3+3] cycloaddition reaction of the azomethine imine with activated cyclopropanes was developed by using EtAlCl2 as a Lewis acid to form hexahydropyridazinone derivatives in high regioselectivity.
Regio- and Stereoselective (SN2) N-, O-, C- and S-Alkylation Using Trialkyl Phosphates
Authors: Banerjee Amit , Hattori Tomohiro , Yamamoto Hisashi 
Published: May 2021

AbstractBimolecular nucleophilic substitution (SN2) is one of the most well-known fundamental reactions in organic chemistry to generate new molecules from two molecules. In principle, a nucleophile attacks from the back side of an alkylating agent having a suitable leaving group, most commonly a halide. However, alkyl halides are expensive, very harmful, toxic and not so stable, which makes them problematic for laboratory use. In contrast, trialkyl phosphates are inexpensive, readily accessible and stable at room temperature, under air, and are easy to handle, but rarely used as alkylating agents in organic synthesis. Here, we describe a mild, straightforward and powerful method for nucleophilic alkylation of various N-, O-, C- and S-nucleophiles using readily available trialkyl phosphates. The reaction proceeds smoothly in excellent yield, and quantitative yield in many cases, and covers a wide range of substrates. Further, the rare stereoselective transfer of secondary alkyl groups has been achieved with inversion of configuration of chiral centers (up to 98% ee).
Physicians' Opinions on Anticoagulant Therapy in Patients with a Limited Life Expectancy
Authors: Huisman Bregje A.A. , Geijteman Eric C.T. , Kolf Nathalie , Dees Marianne K. , van Zuylen Lia , Szadek Karolina M. , Steegers Monique A.H. , van der Heide Agnes 
Published: May 2021

AbstractPatients with a limited life expectancy have an increased risk of thromboembolic and bleeding complications. Anticoagulants are often continued until death, independent of their original indication. We aimed to identify the opinions of physicians about the use of anticoagulants at the end of life. A mixed-method research design was used. A secondary analysis was performed on data from a vignette study and an interview study. Participants included general practitioners and clinical specialists. Physicians varied in their opinions: some would continue and others would stop anticoagulants at the end of life because of the risk of thromboembolic or bleeding complications. The improvement or preservation of patients' quality of life was a reason for both stopping and continuing anticoagulants. Other factors considered in the decision-making were the types of anticoagulant, the indication for which the anticoagulant was prescribed, underlying diseases, and the condition and life expectancy of the patient. Factors that made decision-making difficult were the lack of evidence on either strategy, uncertainty about patients' life expectancy, and the fear of harming patients. Which decision was eventually made seems largely dependent on the choice of the patient. In conclusion, there is a substantial variation in physicians' opinions regarding the use of anticoagulants in patients with a limited life expectancy. Physicians agree that the primary goal of medical care at end of life is the improvement or preservation of patients' quality of life. An important barrier to decision-making is the lack of evidence about the risks and benefits of stopping anticoagulants.