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1.AC/E Accion Cultural Espanola; Q Fundacion Arquia

Author:Sofia Quiroga


2.An Empirical Research on the Investment Strategy of Stock Market based on Deep Reinforcement Learning model

Author:Li, Yuming ; Ni, Pin ; Chang, Victor

Source:COMPLEXIS 2019 - Proceedings of the 4th International Conference on Complexity, Future Information Systems and Risk,2019,Vol.

Abstract:The stock market plays a major role in the entire financial market. How to obtain effective trading signals in the stock market is a topic that stock market has long been discussing. This paper first reviews the Deep Reinforcement Learning theory and model, validates the validity of the model through empirical data, and compares the benefits of the three classical Deep Reinforcement Learning models. From the perspective of the automated stock market investment transaction decision-making mechanism, Deep Reinforcement Learning model has made a useful reference for the construction of investor automation investment model, the construction of stock market investment strategy, the application of artificial intelligence in the field of financial investment and the improvement of investor strategy yield. © 2019 International Conference on Complexity, Future Information Systems and Risk.

3.Clinical Validity and Reliability of the Malay Language Translations of Gastroesophageal Reflux Disease Questionnaire and Quality of Life in Reflux and Dyspepsia Questionnaire in a Primary Care Setting

Author:Vadivelu, S;Ma, ZF;Ong, EW;Hassan, N;Hassan, NFHN;Aziz, SHSA;Kueh, YC;Lee, YY


Abstract:Background: Gastroesophageal Reflux Disease Questionnaire (GERDQ) and Quality of Life in Reflux and Dyspepsia Questionnaire (QOLRAD) are reliable tools for evaluation of GERD. Aim: We aimed to test validity and reliability of Malay language translations of GERDQ and QOLRAD in a primary care setting. Methods: The questionnaires were first translated into the Malay language (GERDQ-M and QOLRAD-M). Patients from primary care clinics with suspected GERD were recruited to complete GERDQ-M, QOLRAD-M, and Malay-translated 36-item short-form health survey (SF-36 or SF36-M), and underwent endoscopy and 24-h pH-impedance test. Results: A total of 104 (mean age 47.1 years, women 51.9%%) participants were enrolled. The sensitivity and specificity for GERDQ-M cut-off score >= 8 were 90.2 and 77.4%%, respectively. Based on this cut-off score, 54.7%% had a high probability of GERD diagnosis. GERD-M score >= 8 vs. <8 was associated with erosive esophagitis (p < 0.001), hiatus hernia (p = 0.03), greater DeMeester score (p = 0.001), and Zerbib scores for acid refluxes (p < 0.001) but not non-acid refluxes (p = 0.1). Mean total scores of QOLRAD-M and SF-36-M were correlated (r = 0.74, p < 0.001). GERDQ-M = 8, erosive esophagitis, and DeMeester >= 14.72 were associated with impaired QOLRAD-M in all domains (all p < 0.02) but this was not seen with SF-36. Conclusions: GERDQ-M and QOLRAD-M are valid and reliable tools applicable in a primary care setting. (C) 2018 S. Karger AG, Basel

4.A multi-objective optimization model for bike-sharing    

Author:Shan, Yu ; Xie, Dejun ; Zhang, Rui

Source:ACM International Conference Proceeding Series,2019,Vol.

Abstract:The study proposes a multi-objective optimization model for bike-sharing industry by monitoring, with high accuracy, the user demand and providing the suitable number of bikes at selected stations. One of the key factors for designing an optimized bike sharing system is to balance the demand of pick-ups (drop-offs) around a given station and the number of available bikes (vacant lockers) in the station throughout the day. The model optimizes the location of bicycle stations and the number of parking slots that each station should have by taking account of the main contributing factors including the total budget of the bike sharing system, the popularity of riding in the city, and the expected proximity of the stations. A case study using the bike-sharing in New York was conducted to test theeffectiveness of themodel. © 2019 Association for Computing Machinery.

5.Material Characterization for Sustainable Concrete Paving Blocks

Author:Wang, XY;Chin, CS;Xia, J


Abstract:Recycled aggregates have been widely studied and used in concrete products nowadays. There are still many waste materials that can be used as recycled aggregates other than crushed concrete particles. This paper aims to study the property variations of sustainable concrete paving block incorporating different contents of construction wastes. Five different types of waste materials were used in this project, including: recycled concrete coarse aggregate (RCCA), recycled concrete fine aggregate (RCFA), crushed glass (CG), crumb rubber (CB), and ground granulated blast furnace slag (GGBS). According to the test results of the properties of blocks mixed with different levels of wastes materials, it is concluded that adding both RCCA and RCFA in the block can decrease its strength and increase the water absorption. The suggested replacement levels for RCCA and RCFA are 60%% and 20%%, respectively. Mixing crushed glass in the concrete paving blocks as a type of coarse aggregates can improve the blocks' strength and decrease the blocks' water absorption. Addition of crumb rubber causes a significant deterioration of blocks' properties except for its slip resistance.

6.Cascode GaN Power Device and Its Application in Wireless Power Transmission System

Author:Qian Hongtu;Zhu Yongsheng;Deng Guangmin;Liu Wen;Chen Dunjun;Pei Yi

Source:Journal of Power Supply,2019,Vol.17

Abstract:To achieve a higher power conversion efficiency, a cascode structure based on 650 V gallium nitride high electron mobility transistor(GaN HEMT) was introduced, together with its applications in wireless power transmission. From the aspect of GaN HEMT design, the effects of field plate design on capacitance and electric field were discussed through simulations. The fabricated cascode device had a leakage current of 2 muA at drain-source voltage of 650 V. At 400 V, the input capacitance C_(iss), the output capacitance C_(oss) and the reverse transfer capacitance Crss were 1 500 pF, 32 pF and 12 pF, respectively, and the dynamic on-resistance increased by about 16%%. Based on the design of this cascode device, a wireless charging prototype with operation frequency of 240~320 kHz and full-load power of 1 kW was designed and presented. Compared with the equivalent Si device, its efficiency was obviously higher within the load range of 200~1 000 W, with the peak efficiency higher than 95%%.

7.A novel cluster HAR-type model for forecasting realized volatility

Author:Yao, XZ;Izzeldin, M;Li, ZX


Abstract:This paper proposes a cluster HAR-type model that adopts the hierarchical clustering technique to form the cascade of heterogeneous volatility components. In contrast to the conventional HAR-type models, the proposed cluster models are based on the relevant lagged volatilities selected by the cluster group Lasso. Our simulation evidence suggests that the cluster group Lasso dominates other alternatives in terms of variable screening and that the cluster HAR serves as the top performer in forecasting the future realized volatility. The forecasting superiority of the cluster models are also demonstrated in an empirical application where the highest forecasting accuracy tends to be achieved by separating the jumps from the continuous sample path volatility process. (C) 2019 International Institute of Forecasters. Published by Elsevier B.V. All rights reserved.

8.Detection of human IgM and IgG antibodies by means of galactofuranose-coated and rhamnose-coated gold nanoparticles

Author:Wang, Xinyue; Chen, Huaiyong; Chiodo, Fabrizio; Tefsen, Boris


Abstract:Many infectious diseases lack cheap, fast, and reliable serodiagnostic tools. Recently, glycans coupled to gold nanoparticles (GNPs) have shown potential to fill this void by utilizing them as a coating in ELISA experiments. In this study, we used GNPs functionalized either with galactofuranose (Galf), rhamnose (Rhap) or a mixture of these monosaccharides to detect the presence of IgM and IgG antibodies against these non-human carbohydrates in sera obtained from tuberculosis patients and control groups. Our findings confirm the wide abundance of anti-Rhap antibodies in humans and show for the first time the presence of anti-Galf antibodies in human sera. This study supports further investigation of using GNP-ELISA with microbe-specific carbohydrates for serodiagnosis of infectious diseases.

9.SPHERE dynamical and spectroscopic characterization of HD142527B

Author:Claudi, R;Maire, AL;Mesa, D;Cheetham, A;Fontanive, C;Gratton, R;Zurlo, A;Avenhaus, H;Bhowmik, T;Biller, B;Boccaletti, A;Bonavita, M;Bonnefoy, M;Cascone, E;Chauvin, G;Delboulbe, A;Desidera, S;D'Orazi, V;Feautrier, P;Feldt, M;Dotti, FF;Girard, JH;Giro, E;Janson, M;Hagelberg, J;Keppler, M;Kopytova, T;Lacour, S;Lagrange, AM;Langlois, M;Lannier, J;Le Coroller, H;Menard, F;Messina, S;Meyer, M;Millward, M;Olofsson, J;Pavlov, A;Peretti, S;Perrot, C;Pinte, C;Pragt, J;Ramos, J;Rochat, S;Rodet, L;Roelfsema, R;Rouan, D;Salter, G;Schmidt, T;Sissa, E;Thebault, P;Udry, S;Vigan, A


Abstract:Aims. HD142527 is one of the most frequently studied Herbig Ae/Be stars with a transitional disk that hosts a large cavity that is up to about 100 au in radius. For this reason, it has been included in the guaranteed time observation (GTO) SpHere INfrared survey for Exoplanets (SHINE) as part of the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) at the Very Large Telescope (VLT) in order to search for low-mass companions that might explain the presence of the gap. SHINE is a large survey within about 600 young nearby stars are observed with SPHERE with the aim to constrain the occurrence and orbital properties of the giant planet population at large (>5 au) orbital separation around young stars. Methods. We used the IRDIFS observing mode of SPHERE (IRDIS short for infrared dual imaging and spectrograph plus IFS or integral field spectrograph) without any coronagraph in order to search for and characterize companions as close as 30 mas of the star. Furthermore, we present the first observations that ever used the sparse aperture mask (SAM) for SPHERE both in IRDIFS and IRDIFS_EXT modes. All the data were reduced using the dedicated SPHERE pipeline and dedicated algorithms that make use of the principal component analysis (PCA) and reference differential imaging (RDI) techniques. Results. We detect the accreting low-mass companion HD142527B at a separation of 73 mas (11.4 au) from the star. No other companions with mass greater than 10 M-J are visible in the field of view of IFS (similar to 100 au centered on the star) or in the IRDIS field of view (similar to 400 au centered on the star). Measurements from IFS, SAM IFS, and IRDIS suggest an M6 spectral type for HD142527B, with an uncertainty of one spectral subtype, compatible with an object of M = 0.11 +/- 0.06 M-circle dot and R = 0.15 +/- 0.07 R-circle dot. The determination of the mass remains a challenge using contemporary evolutionary models, as they do not account for the energy input due to accretion from infalling material. We consider that the spectral type of the secondary may also be earlier than the type we derived from IFS spectra. From dynamical considerations, we further constrain the mass to 0.26(-0.14)(+0.16) , which is consistent with both our spectroscopic analysis and the values reported in the literature. Following previous methods, the lower and upper dynamical mass values correspond to a spectral type between M2.5 and M5.5 for the companion. By fitting the astrometric points, we find the following orbital parameters: a period of P = 35 137 yr; an inclination of i = 121 130 degrees, a value of Omega = 124 135 degrees for the longitude of node, and an 68%% confidence interval of similar to 18-57 au for the separation at periapsis. Eccentricity and time at periapsis passage exhibit two groups of values: similar to 0.2-0.45 and similar to 0.45-0.7 for e, and similar to 2015-2020 and similar to 2020-2022 for T-0. While these orbital parameters might at first suggest that HD142527B is not the companion responsible for the outer disk truncation, a previous hydrodynamical analysis of this system showed that they are compatible with a companion that is able to produce the large cavity and other observed features.

10.AlGaN/GaN Metal-Insulator-Semiconductor (MIS)-HFETs Based DC-DC Boost Converters with Integrated Gate Drivers

Author:Cui, M;Bu, QL;Cai, YT;Sun, RZ;Liu, W;Wen, HQ;Lam, S;Liang, YC;Mitrovic, IZ;Taylor, S;Chalker, PR;Zhao, CZ


Abstract:This study proposed a 100 kHz, 5V/11V boost converter with an integrated gate driver for a power switching device using recessed E-mode MIS-HFETs. The integrated gate driver consisting of multi-stages DCFL (Direct-Coupled FET Logic) inverters and a buffer stage, has large input swing (up to 10 V) and wide noise margin with gate dielectric, which benefits applications requiring large gate swing without any additional drivers or level shifters. The impact of transistor size on rise times and fall times have been studied. Either buffer stage or larger width of DCFL inverter can reduce rise times from 2.4 mu s to less than 0.5 mu s at 100 kHz, so the output voltage of boost converter is increased by 10 %% at a duty cycle of 0.7. However, large buffer width can result in high gate overshoot and oscillation, indicating careful design to balance switching speed and oscillation.

11.Topical treatments and photodynamic therapy for actinic keratosis of the face and scalp

Author:Foley,Kelly;Gupta,Aditya K.;Martin,George;Tweed,John A.;Villanueva,Elmer;Carviel,Jessie

Source:Cochrane Database of Systematic Reviews,2019,Vol.2019

Abstract:This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the effects of topical interventions and photodynamic therapy as monotherapy or combination therapy for treatment of actinic keratoses on the face and scalp (which includes lip, face, and scalp) of immunocompetent (i.e. normal immune response) adults.

12.Chinese EFL academics' perceptions of research quality: a phenomenological study

Author:Xie, JM;Postlethwaite, K


Abstract:This paper explores how Chinese academics, working in the field of English as Foreign Language Education in universities in China, conceptualise research quality. The paper uses a phenomenological approach and four qualitative methods (survey, interview, focus groups and document analysis) to investigate what a sample of these scholars perceive as high-quality research. We found that the participants viewed quality through various lenses and identified several different criteria. We categorised their elaboration of the criteria under three headings: methodology, contextualisation and impact. The participants nominated many general criteria that were similar to western standards of research quality, especially in relation to methodology; however, some contextual criteria were specific to the Chinese context. The paper indicates that there is much in the university research community that could be altered to enable people who are directly involved in research to disseminate their criteria for research quality, and potentially to affect and develop the quality of educational research in the Chinese context, and/or elsewhere.

13.Production of "biobetter" variants of glucarpidase with enhanced enzyme activity

Author:Al-Qahtani, AD;Bashraheel, SS;Rashidi, FB;O'Connor, CD;Romero, AR;Domling, A;Goda, SK


Abstract:Glucarpidase, also known as carboxypeptidase G(2), is a Food and Drug Administration-approved enzyme used in targeted cancer strategies such as antibody-directed enzyme prodrug therapy (ADEPT). It is also used in drug detoxification when cancer patients have excessive levels of the anti-cancer agent methotrexate. The application of glucarpidase is limited by its potential immunogenicity and limited catalytic efficiency. To overcome these pitfalls, mutagenesis was applied to the glucarpidase gene of Pseudomonas sp. strain RS-16 to isolate three novels "biobetter" variants with higher specific enzyme activity. DNA sequence analysis of the genes for the variants showed that each had a single point mutation, resulting in the amino acid substitutions: I100 T, G123S and T239 A. K-m, V-max and K-cat measurements confirmed that each variant had increased catalytic efficiency relative to wild type glucarpidase. Additionally, circular dichroism studies indicated that they had a higher alpha-helical content relative to the wild type enzyme. However, three different software packages predicted that they had reduced protein stability, which is consistent with having higher activities as a tradeoff. The novel glucarpidase variants presented in this work could pave the way for more efficient drug detoxification and might allow dose escalation during chemotherapy. They also have the potential to increase the efficiency of ADEPT and to reduce the number of treatment cycles, thereby reducing the risk that patients will develop antibodies to glucarpidase.

14.Video Streaming Adaptation Strategy for Multiview Navigation Over DASH

Author:Yao, C;Xiao, JM;Zhao, Y;Ming, AL


Abstract:Video content delivery over Internet is receiving increasing attention from both industry and academia, especially for the multiview video contents, as it is the basis to support various applications, such as 3-D video, virtual reality, free view video, and so on. To cope with the dynamic nature of Internet throughput, dynamic adaptive streaming over HTTP (DASH) has been introduced to control the video streaming based on the network conditions. In this paper, we design a streaming framework to improve the user experience of the multiview video streaming over DASH, considering the user behavior of the viewpoint navigation during the streaming process. To eliminate the view switching delay, a multiple view navigation rule is introduced to pre-fetch the possible switching viewpoints. An optimal bitrate allocation scheme is proposed for the introduced rule, allowing the clients to maximize the video quality. Moreover, we found the video quality and the playback starvation probability are conflicting factors, while both are essential for the user's quality of experience (QoE). To tackle this issue, a QoE optimization solution is designed to maximize the overall performance in the proposed framework. Several experiments verify the effectiveness of the proposed framework, and the results demonstrate that the proposed framework outperforms two typical DASH methods.

15.Dynamic capabilities and organizational performance: The mediating role of innovation

Author:Zhou, SS;Zhou, AJ;Feng, JZ;Jiang, SS


Abstract:How firms' dynamic capabilities lead to their competitive advantage and improved firm performance has been a core issue and full of debates. In this research, we theorize that dynamic capabilities, which could be defined by three distinct dimensions (sensing capability, integration capability, and reconfiguration capability), facilitate different types of innovation that in turn improve firm performance. Based on a sample of 204 Chinese firms, results from partial least squares structural equation modeling analyses generally support our arguments despite some nuanced differences existing among different dimensions of dynamic capabilities. This study contributes to dynamic capabilities literature by reducing the scarcity of empirical research and by uncovering the mechanisms through which dynamic capabilities influence firm performance.

16.A Catalog of Newly Identified Star Clusters in Gaia DR2

Author:Liu, L;Pang, XY


Abstract:We present the Star cluster Hunting Pipeline (SHiP) that can identify star clusters in Gaia second data release (DR2) data and establish a star cluster catalog for the Galactic disk. A friend-of-friend-based cluster finder method is used to identify star clusters using five-dimensional stellar parameters, l, b, omega, mu(alpha) cos delta, and mu(delta). Our new catalog contains 2443 star cluster candidates identified from disk stars located within vertical bar b vertical bar = 25. and with G < 18 mag. An automatic isochrone fitting scheme is applied to all cluster candidates. With a combination of parameters obtained from isochrone fitting, we classify cluster candidates into three classes (Class 1, 2, and 3). Class 1 clusters are the most probable star cluster candidates with the most stringent criteria. Most of these clusters are nearby (within 4 kpc). Our catalog is crossmatched with three Galactic star cluster catalogs, Kharchenko et al., Gaudin et al., and Bica et al. The proper motion and parallax of matched star clusters are in good agreement with these earlier catalogs. We discover 76 new star cluster candidates that are not listed in these three catalogs. The majority of these are clusters older than log(age/yr) = 8.0 and are located in the inner disk with vertical bar b vertical bar < 5 degrees. The recent discovery of new star clusters suggests that current Galactic star cluster catalogs are still incomplete. Among the Class 1 cluster candidates, we find 56 candidates for star cluster groups. The pipeline, the catalog, and the member list containing all candidates star clusters and star cluster groups have been made publicly available.

17.Building infrastructure and making boundaries in Southwest China


Source:It Happens among People: Resonances and Extensions of the Work of Fredrik Barth,2019,Vol.

18.Putting student partnership and collaboration centre-stage in a research-led context: A case study of the Summer Undergraduate Research Fellowship programme at Xi’an Jiaotong-Liverpool University

Author:Huijser, H., Wilson, J., Wu, Y., Qiu, S., Wang, K., Li, S., Chen, W., & Kouwenhoven, M.

Source:International Journal for Students as Partners,2019,Vol.3

Abstract:In this case study, we evaluated the Summer Undergraduate Research Fellowship (SURF) initiative at Xi’an Jiaotong-Liverpool University (XJTLU), an extracurricular programme that focuses on academic staff-student partnerships and collaborations. While not directly integrated into university degree programmes, SURF provides students with the opportunity to develop practical research skills related to knowledge they have acquired in class. Participating students receive an authentic research experience, which involves collaboration on research projects with academic staff. All students are required to present results of their projects at a public poster presentation event organised by the university. This case study is a partnership between Academic Enhancement Centre (AEC) staff, who organize and run SURF, SURF students, and a lecturer (M.B.N. Kouwenhoven), and it presents a reflection on their experiences of the SURF programme, and in particular on the notions of partnership and collaboration and the potential tension between those two concepts.

19.Effect of Annealing Temperature for Ni/AlOx/Pt RRAM Devices Fabricated with Solution-Based Dielectric

Author:Shen, ZJ;Qi, YF;Mitrovic, IZ;Zhao, CZ;Hall, S;Yang, L;Luo, T;Huang, YB;Zhao, C


Abstract:Resistive random access memory (RRAM) devices with Ni/AlOx/Pt-structure were manufactured by deposition of a solution-based aluminum oxide (AlOx) dielectric layer which was subsequently annealed at temperatures from 200 degrees C to 300 degrees C, in increments of 25 degrees C. The devices displayed typical bipolar resistive switching characteristics. Investigations were carried out on the effect of different annealing temperatures for associated RRAM devices to show that performance was correlated with changes of hydroxyl group concentration in the AlOx thin films. The annealing temperature of 250 degrees C was found to be optimal for the dielectric layer, exhibiting superior performance of the RRAM devices with the lowest operation voltage (<1.5 V), the highest ON/OFF ratio (>10(4)), the narrowest resistance distribution, the longest retention time (>10(4) s) and the most endurance cycles (>150).

20.Multiview video quality enhancement without depth information

Author:Jammal, S;Tillo, T;Xiao, JM


Abstract:The past decade has witnessed fast development in multiview 3D video technologies, such as Three-Dimensional Video (3DV), Virtual Reality (VR), and Free Viewpoint Video (FVV). However, large information redundancy and a vast amount of multiview video data needs to be stored or transmitted, which poses a serious problem for multiview video systems. Asymmetric multiview video compression can alleviate this problem by coding views with different qualities. Only several viewpoints are kept with high-quality and other views are highly compressed to low-quality. However, highly compressed views may incur severe quality degradation. Thus, it is necessary to enhance the visual quality of highly compressed views at the decoder side. Exploiting similarities among the multiview images is the key to efficiently reconstruct the multiview compressed views. In this paper, we propose a novel method for multiview quality enhancement, which directly learns an end-to-end mapping between the low-quality and high-quality views and recovers the details of the low-quality view. The mapping process is realized using a deep convolutional neural network (MVENet). MVENet takes a low-quality image of one view and a high-quality image of another view of the same scene as inputs and outputs an enhanced image for the low-quality view. To the best of our knowledge, this is the first work for multiview video enhancement where neither a depth map nor a projected virtual view is required in the enhancement process. Experimental results on both computer graphic and real datasets demonstrate the effectiveness of the proposed approach with a peak signal-to-noise ratio (PSNR) gain of up to 2dB over low-quality compressed views using HEVC and up to 3.7dB over low-quality compressed views using JPEG on the benchmark Cityscapes.
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