76059 research outputs found
Sort by
Design and Verification for the Torque Improvement of a Concentrated Flux-type Synchronous Motor for Automotive Applications
No full textIn this paper, the design of the concentrated flux-type synchronous motor (CFSM) using ferrite permanent magnets to improve torque is proposed for an automotive chassis actuator. The thin pancake type CFSM of this paper has considerable axial magnetic leakage flux due to structural reasons. It is, therefore, necessary to improve the torque. In order to meet the required specifications in a constrained installation space, this paper proposes two methods for torque improvement. The first method is the alternate-stacking core as this structure removes the magnetic leakage flux path. The second method is the rotor overhang that increases the air-gap flux density. Furthermore, the structures require a three-dimensional (3-D) finite element method (FEM) analysis for accuracy. However, to analyze the characteristics easily and quickly, the 3-D structure is made into the equivalent 2-D FEM through an analytical method using an equivalent magnetic circuit. Finally, in this paper, the validity of the design process and the effectiveness for torque improvement is verified through experiments
Search for the pair production of light top squarks in the e(+/-)mu(-/+) final state in proton-proton collisions at root s=13 TeV
No full textA search for the production of a pair of top squarks at the LHC is presented. This search targets a region of parameter space where the kinematics of top squark pair production and top quark pair production are very similar, because of the mass difference between the top squark and the neutralino being close to the top quark mass. The search is performed with 35.9 fb(-1) of proton-proton collisions at a centre-of-mass energy of root s = 13 TeV, collected by the CMS detector in 2016, using events containing one electron-muon pair with opposite charge. The search is based on a precise estimate of the top quark pair background, and the use of the M-T2 variable, which combines the transverse mass of each lepton and the missing transverse momentum. No excess of events is found over the standard model predictions. Exclusion limits are placed at 95% confidence level on the production of top squarks up to masses of 208 GeV for models with a mass difference between the top squark and the lightest neutralino close to that of the top quark.We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centres and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI, and FEDER (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU and SFFR (Ukraine); STFC (United Kingdom); DOE and NSF (U.S.A.).r Individuals have received support from the Marie-Curie program and the European Research Council and Horizon 2020 Grant, contract No. 675440 (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the F.R.S.-FNRS and FWO (Belgium) under the "Excellence of Science - EOS" - be.h project n. 30820817; the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Lendulet ("Momentum") Program and the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences, the New National Excellence Program UNKP, the NKFIA research grants 123842, 123959, 124845, 124850 and 125105 (Hungary); the Council of Science and Industrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus program of the Ministry of Science and Higher Education, the National Science Center (Poland), contracts Harmonia 2014/14/M/ST2/00428, Opus 2014/13/B/ST2/02543, 2014/15/B/ST2/03998, and 2015/19/B/ST2/02861, Sonata-bis 2012/07/E/ST2/01406; the National Priorities Research Program by Qatar National Research Fund; the Programa Estatal de Fomento de la Investigaci on Cientfica y Tecnica de Excelencia Maria de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias; the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University and the Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand); the Welch Foundation, contract C-1845; and the Weston Havens Foundation (U.S.A.)
Search for pair production of first-generation scalar leptoquarks at root s=13 TeV
No full textA search for the pair production of first-generation scalar leptoquarks is performed using proton-proton collision data recorded at 13 TeV center-of-mass energy with the CMS detector at the LHC. The data correspond to an integrated luminosity of 35.9 fb(-1). The leptoquarks are assumed to decay promptly to a quark and either an electron or a neutrino, with branching fractions beta and 1 - beta, respectively. The search targets the decay final states comprising two electrons, or one electron and large missing transverse momentum, along with two quarks that are detected as hadronic jets. First-generation scalar leptoquarks with masses below 1435 (1270) GeVare excluded for beta = 1.0(0.5). These are the most stringent limits on the mass of first-generation scalar leptoquarks to date. The data are also interpreted to set exclusion limits in the context of an R-parity violating supersymmetric model, predicting promptly decaying top squarks with a similar dielectron final state.We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMBWF and FIVE (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DEG, and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT; LNS; SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI; CPAN; PCTI, and FEDER (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASD and SFER (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie Curie program and the European Research Council and Horizon 2020 Grant, Contract No. 675440 (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l' Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the F. R. S.-FNRS and FWO (Belgium) under the "Excellence of Science-EOS"-be.h Project No. 30820817; the Ministry of Education. Youth and Sports (MEYS) of the Czech Republic; the Lendulet ("Momentum") Program and the Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences, the New National Excellence Program UNKP, the NKFIA Research Grants No. 123842, No. 123959, No. 124845, No. 124850, and No. 125105 (Hungary); the Council of Science and Industrial Research, India; the HOMING PLUS program of the Foundation for Polish Science, cofinanced from European Union, Regional Development Fund, the Mobility Plus program of the Ministry of Science and Higher Education, the National Science Center (Poland), Contracts Harmonia No. 2014/14/M/ST2/00428, Opus No. 2014/13/B/ST2/02543, No. 2014/15/B/ST2/03998, and No. 2015/19/B/ST2/02861, Sonata-bis No. 2012/07/E/ST2/01406; the National Priorities Research Program by Qatar National Research Fund; the Programa Estatal de Foment de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu, Grant No. MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias; the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF; the Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkom University and the Chulalongkom Academic into Its 2nd Century Project Advancement Project (Thailand); the Welch Foundation, contract C-1845; and the Weston Havens Foundation (USA)
Characterization of chitosan extracted from Mealworm Beetle (Tenebrio molitor, Zophobas mono) and Rhinoceros Beetle (Allomyrina dichotoma) and their antibacterial activities
No full textChitin was isolated from the larvae, adult, and superworm of Mealworm Beetle and the larvae, pupa, and adult of Rhinoceros Beetle by deproteinization and demineralization. Chitin yields were 4.60, 8.40, and 3.90% in the larvae, adult, and superworm of Mealworm Beetle and 10.53,12.70, and 14.20% in the larvae, pupa, and adult of Rhinoceros Beetle, respectively. Subsequently, chitosan was obtained by deacetylation of chitin extractions from all stages of both beetle species, and its yields from chitin were 80.00, 78.33, and 83.33% in the larvae, adult, and superworm of Mealworm Beetle, and 83.37, 83.37, and 75.00% in larvae, pupa, and adult of Rhinoceros Beetle, respectively. The Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis of the chitosan from the two insect species showed the similar structural characteristics as those of commercial chitosan. Chitosan from the Mealworm Beetle showed about 1 mm inhibition zones against Bacillus cereus, Listeria monocytogenes, and Escherischia coli, and a 2 mm inhibition zone against Staphylococcus aureus in antimicrobial activity test. (C) 2018 Elsevier B.V. All rights reserved.This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1D1A1A09061228)
Enrichment of vascular endothelial growth factor secreting mesenchymal stromal cells enhances therapeutic angiogenesis in a mouse model of hind limb ischemia
No full textCritical limb ischemia, a severe manifestation of peripheral artery disease, is emerging as a major concern in aging societies worldwide. Notably, cell-based gene therapy to induce angiogenesis in ischemic tissue has been investigated as treatment. Despite many studies demonstrating the efficacy of this approach, better therapies are required to prevent serious sequelae such as claudication, amputation and other cardiovascular events. We have now established a simplified method to enhance the effects of therapeutic transgenes by selecting for and transplanting only transduced cells. Herein, mesenchymal stromal cells were transfected to co-express vascular endothelial growth factor as angiogenic factor and enhanced green fluorescent protein as marker. Transfected cells were then collected using flow cytometry based on green fluorescence and transplanted into ischemic hind limbs in mice. Compared with unsorted or untransfected cells, purified cells significantly improved blood perfusion within 21 days, suggesting that transplanting only cells that overexpress vascular endothelial growth factor enhances therapeutic angiogenesis. Importantly, this approach may prove to be useful in cell-based gene therapy against a wide spectrum of diseases, simply by replacing the gene to be delivered or the cell to be transplanted.This research was supported by a grant from the Korea Healthcare Technology Research & Development Project, Ministry for Health & Welfare, Republic of Korea (numbers A085136 and HI15C1277), the Mid-Career Researcher Program through an national research foundation of korea (NRF) grant funded by the ministry of education, science and technology (MEST), Republic of Korea (number 2015R1A2A2A01002731), the Bio & Medical Technology Development Program of the NRF funded by Korean government, ministry of science, ICT and future planning (MSIP) 2015M3A9C6031514 and the Cardiovascular Research Center, Seoul, Korea
Latent class analysis of no-formal learners’ self-directed learning patterns in open educational resource repositories
No full textOpen educational resources (OERs) are increasingly adopted in non���formal education contexts. However, little research has been conducted to investigate the self���directed learning patterns of non���formal learners using OERs. A lack of knowledge about non���formal learners precludes discussions on how to support their self���regulated learning in open learning environments. We explored the self���directed learning patterns of 1892 non���formal online learners who were using OER repositories. In addition, we examined whether differences existed in future intentions to use OERs between learners with different learning patterns. Four latent classes were identified, and learners’ age was found to affect class membership. We also found that non���formal learners’ use of self���directed learning strategies predicted their future intentions to use OERs. This study advanced our understanding of the subpopulations of non���formal learners using OERs. Future research will benefit from the findings related to designing OER environments that can accommodate diverse self���directed learners.This work was supported by Global Research Network program through the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF2017S1A2A2040115). We also would like to show our gratitude to the Open Education Research Hub (https://oerhub.net/) for sharing their data. The data set we used in this study has been published under the Creative Commons Attribution License (CC-BY 4.0)
Establishing a human adrenocortical carcinoma (ACC)-specific gene mutation signature
No full textAdrenocortical carcinoma (ACC) is a rare and aggressive tumor whose molecular signaling pathways are not fully understood. Using an in-silico clinical data analysis approach we retrieved human gene mutation data from the highly reputed Cancer Genome Atlas (TCGA). ACC-specific gene mutations were correlated with proliferation marker FAM72 expression and Mutsig along with the algorithmic implementation of the 20/20 rule were used to validate their oncogenic potential. The newly identified oncogenic driver gene set (ZFPM1, LRIG1, CRIPAK, ZNF517, GARS and DGKZ), specifically and most repeatedly mutated in ACC, is involved in tumor suppression and cellular proliferation and thus could be useful for the prognosis and development of therapeutic approaches for the treatment of ACC.This study was supported by Hanyang University by providing a scholarship to C.S.R. and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2015R1D1A1A01057243 and 201681D1A1B03932599)
Energy Saving Potential and Indoor Air Quality Benefits of Multiple Zone Dedicated Outdoor Air System
No full textThe purpose of this study is to evaluate the indoor air quality (IAQ) and energy benefits of a dedicated outdoor air system (DOAS) and compare them with a conventional variable air volume (VAV) system. The DOAS is a decoupled system that supplies only outdoor air, while reducing its consumption using an enthalpy wheel. The VAV system supplies air that is mixed outdoor and transferred indoor. The VAV has the issue of unbalanced ventilation in each room in multiple zones because it supplies mixing air. The DOAS does not have this problem because it supplies only outdoor air. That is, the DOAS is a 100% outdoor air system and the VAV is an air conditioning system. The transient simulations of carbon dioxide concentration and energy consumption were performed using a MATLAB program based on the thermal loads from the model predicted by the TRNSYS 18 program. The results indicated that when the air volume is large, such as in summer, the distribution of air is not appropriate in the VAV system. The DOAS however, supplies the outdoor air stably. Moreover, in terms of annual primary energy consumption, the DOAS consumed approximately 40% less energy than the VAV system.This work was supported by the Korea Agency for Infrastructure Technology Advancement (KAIA) grants (19CTAP-C141826-02)
Highly Bendable and Rotational Textile Structure with Prestrained Conductive Sewing Pattern for Human Joint Monitoring
No full textHuman joints have respective ranges of motion and joint forces corresponding to each kind of joint; this necessitates considerations of the characteristics of human joints to fabricate wearable strain sensors conformable to the human body, and capable of precisely monitoring complex motions of the human body. In the present study, the "all textile-based highly stretchable structure" that is capable of precisely sensing motions (folding and rotation) of the human joints (finger, wrist, elbow, spine, and knee) is fabricated by optimizing patterns (straight, blind, and zigzag) of conductive yarns employed as the conductive part of the strain sensor, and several textile substrates (braided elastic fabric, knit fabric, and woven fabric), having preferable elasticity and conformability employed for the fabrication of strain sensors suitable for human joints. In particular, the technology, enabling the prestraining of textile substrate, is exploited to fabricate a strain sensor that is capable of outputting selective signals corresponding to the folding motion of the spinal joint over a predetermined angle of motion, and the gait pattern of the wearer of the sensor, attached to his or her knee joint doing folding and rotational motions, is analyzed.This research was financially supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1D1A1A01057245 and NRF-2018R1A2B6005220) and additional support was provided by the Ministry of Trade, Industry & Energy (MOTIE, Korea) under the Industrial Technology Innovation Program 10067151, smart device connected and textile-based smart function mounted outdoor garment for smart life with ergonomic design
Optimal design of PZT-based piezoelectric energy harvesting module for availability
No full textIn the context of reliability and maintainability, availability is either the probability that a system performs a required function at a specified time or within a required period or the ratio of the spent time against a period. Hence, availability is roughly similar to the operation ratio. The availability of a facility is directly related to costs when designing a large-scale facility, such as a nuclear power or manufacturing plant. A renewable energy system must also consider availability to produce a large quantity of electricity sustainably. This study designed a piezoelectric energy harvesting module that is integrated with a large quantity of PZT material and circuits in consideration of availability. Each component is prone to failure because the piezoelectric effect converts vibrated mechanical energy into electrical energy, and this can seriously degrade the performance of the entire module or cause total failure. Thus, availability needs to be considered at the conceptual design stage. In this study, we analyzed each component's possible failure modes and calculated reliability based on the failure modes to evaluate the availability of the module. We examined the characteristics of availability, which could be changed by the different series and parallel combinations of the PZT material from which energy was extracted. We designed optimal combinations of series and parallel circuit configurations to secure the required availability and proposed the maintenance cycle of the piezoelectric energy harvesting module.This research is supported by a grant from Endowment Project of "Technology development of material handling and risk management for operation and maintenance service of offshore plant" funded by the Korea Research Institute of Ships and Ocean Engineering (2019, PES3081)