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Nano-Micro Letters 2022年第12期14卷 432-446页

作者： dong seob chung Tyler Davidson-Hall Giovanni Cotella Quan Lyu Peter Chun Hany Aziz Department of Electrical and Computer Engineering Waterloo Institute for NanotechnologyUniversity of Waterloo200 University Avenue WestWaterlooON N2L 3G1Canada Ipswich Research Centre Huawei Technologies Research&Development(UK)Ltd.Phoenix House(B55)Adastral ParkIpswich IP53REUK Ottawa IC Laboratory Huawei Canada19 Allstate ParkwayMarkhamON L3R 5B4Canada

ZnO nanoparticles are widely used for the electron transport layers(ETLs)of quantum dots light emitting devices(QLEDs).In this work we show that incorporating fluorine(F)into the ZnO ETL results in significant enhancement in device electroluminescence stability,leading to LT50 at 100 cd m^(−2) of 2,370,000 h in red QLED,47X longer than the control devices.X-ray photo-electron spectroscopy,time-of-flight secondary ion mass spectroscopy,photoluminescence and electrical measurements show that the F passivates oxygen vacancies and reduces electron traps in *** photoluminescence versus bias measurements and capacitance-voltage-luminance measurements reveal that the CF4 plasma-treated ETLs lead to increased electron concentration in the QD and the QD/hole transport layer interface,subsequently decreasing hole accumulation,and hence the higher *** findings provide new insights into the critical roles that optimizing charge distribution across the layers play in influencing stability and present a novel and simple approach for extending QLED lifetimes.

关键词： Colloidal quantum dots Quantum dots light emitting device Device stability Zinc oxide nanoparticles Fluorine

Influence of the electrolyte conductivity on the critical current density and the breakdown voltage

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Chinese Journal of Chemical Engineering 2023年第7期59卷 169-175页

作者： Hae-Kyun Park dong-Hyuk Park Bum-Jin chung Department of Nuclear Engineering Kyung Hee University 1732 Deogyeong-daeroGiheung-guYongin-siGyeonggi-do 17104Korea

The work investigates influence of the electrolyte conductivity on the onset of partial contact glow discharge electrolysis(CGDE)in a water *** current density(CCD)and breakdown voltage were measured together with in situ observation of hydrogen bubble behavior,whose influence has not been focused *** a fixed current during normal electrolysis,hydrogen coalescence adjacent to cathode surface was invigorated at a lower *** analyses elucidated the hydrogen coalescence characteristics by quantifying size and population of detached hydrogen *** CCD increased about 104% within given range of conductivity(11.50-127.48 mS·cm^(-1))due to impaired bubble coalescence,which delays hydrogen film formation on the ***,decreasing trend of breakdown voltage was measured with increased conductivity showing maximum drop of 74%.It is concluded that onset of partial CGDE is directly affected by hydrodynamic bubble behaviors,whereas the electrolyte conductivity affects the bubble formation characteristics adjacent to cathode electrode.

关键词： Water electrolysis Critical current density Breakdown voltage Electrolyte conductivity Hydrogen bubble behavior

Bilateral superficial cervical plexus block for parathyroidectomy during pregnancy:A case report

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World Journal of Clinical Cases 2022年第13期10卷 4153-4160页

作者： Jun-Young chung Yo seob Lee Seung Yeon Pyeon Sang-Ah Han Hyub Huh Department of Anesthesiology and Pain Medicine Kyung Hee University Hospital at GangdongCollege of MedicineKyung Hee UniversitySeoul 05278South Korea Department of Obstetrics&Gynecology Kyung Hee University Hospital at GangdongCollege of MedicineKyung Hee UniversitySeoul 05278South Korea Department of Surgery Kyung Hee University Hospital at GangdongCollege of MedicineKyung Hee UniversitySeoul 05278South Korea

BACKGROUND Primary hyperparathyroidism(PHPT)is the most common cause of pregnancyrelated *** can cause maternal and fetal complications in pregnant *** anesthesia for non-obstetric surgery in pregnant women is associated with maternal hazards and concerns regarding long-term neonatal neurocognitive *** removal of the lesion in mid-pregnancy is currently the primary treatment option for pregnant patients with ***,the blood calcium concentration at which surgery should be considered remains under discussion due to the risk of *** SUMMARY A 31-year-old nulliparous woman at 11 wk of gestation was admitted to our hospital for *** patient had a history of intrauterine fetal death with unknown etiology at 16 wk of gestation 1 year *** blood test results showed that the serum calcium level was elevated to 12.9 mg/dL,and the parathyroid hormone level was elevated to 157 pg/*** a neck ultrasound,it revealed a 0.8 cm×1.5 cm sized oval,hypoechoic mass in the upper posterior of the left thyroid gland,which was compatible with parathyroid *** cervical plexus block(SCPB)for parathyroidectomy was *** surgery,the obstetrician checked the status of the fetus,and there were no abnormal *** then her calcium level returned to normal values after one week of surgery and a healthy male neonate of 2910 g was delivered vaginally at 38 wk of *** Our case suggests that SCPB can be an anesthetic option for parathyroidectomy during the first trimester of pregnancy.

关键词： Bilateral superficial cervical plexus block Hypercalcemia Parathyroid adenoma Parathyroidectomy Pregnancy Case report

Korea Institute of Sport Science:Past,Present and Future

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中国体育科技 2009年第1期45卷 14-18页

作者： dong-Sik chung Korea Institute of Sport Science

Introduction Korea Institute of Sport Science (KISS,formerly named as Korea Sport Science Institute:KSSI) was established on December 29th,1980 to perform research and provide support for better performance of the national *** had clear objective of supporting scientifi c training of national athletes for successful hosting of 1986 Asian Games and 1988 Olympics,both were to be held in Seoul,Korea. The objective was successfully achieved with strong support from the government.

关键词：运动员体育训练训练方法科学训练

Short Form of Weinstein Noise Sensitivity Scale(NSS-SF): Reliability, Validity and Gender Invariance among Chinese Individuals

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Biomedical and Environmental Sciences 2018年第2期31卷 97-105页

作者： ZHONG Tao chung Pak-kwong LIU Jing dong Faculty of Social Science Hong Kong Baptist University

Objective Independent from noise exposure, noise sensitivity plays a pivotal role in people＇s noise annoyance perception and concomitant health deteriorations. The present study empirically investigated the psychometric properties of the Chinese version of the Weinstein Noise Sensitivity Scale-Short Form （CNSS-SF）, the widely used inventory measuring individual differences in noise *** In total, 373 Chinese participants （age = 21.41 ± 3.36） completed the online, anonymous questionnaire package. Examination of the CNSS-SF＇s reliability （internal consistency）, factorial validity through validation and cross-validation, nomological validity and measurement invariance across gender groups were *** The Cronbach alpha coefficients and composite reliabilities indicated sufficient reliability of the CNSS-SF. Two confirmatory factor analyses （CFA）, in two randomly partitioned groups of participants, substantiated the factorial validity of the scale. The nomological validity of the scale was also corroborated by the significant positive association of its score with the trait anxiety score. Measurement invariance of the CNSS-SF was also found across genders via multi-group *** Though not without limitations, findings from the present research provide promising evidence for the utility of the scale in measuring noise sensitivity among the Chinese population. The availability of the CNSS-SF can promote research related to environmental noise and health in China, as well as facilitate cross-cultural comparisons.

关键词： Environmental noise Individual differences Cross-cultural validation Measurement Publichealth

Convergent adaptive evolution——how common, or how rare?

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National Science Review 2020年第6期7卷 945-946页

作者： chung-I Wu Guo-dong Wang Shuhua Xu School of Life Sciences Sun Yat-Sen University Kunming Institute of Zoology Chinese Academy of Sciences Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences CAS-MPG Partner Institute for Computational Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences

This Special Topic contains one perspective and three original articles that address the topic of convergent evolution. How common, and how important, is convergent adaptation in evolution? These are the questions the...

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Experimental Investigation of Flexible Hawkmoth-like Wings on the Wing-wake Interaction in Hovering Flight

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Journal of Bionic Engineering 2018年第1期15卷 139-153页

作者： YeongGyun Ryu Jo Won Chang Joon chung dong-Ha Kim Department of Aerospace Engineering Ryerson University Toronto Ontario M5B 2K3 Canada Department of Aeronautical Science and Flight Operation Korea Aerospace University 76 Hanggongdaehak-ro Deogyang-gu Goyang-si Gyeonggi-do 10540 Republic of Korea Aerodynamics Group Korean Air R&D Center Daejeon Metropolitan City 34054 Republic of Korea

To study wing-wake interaction for various wing flexibilities, force measurements and digital particle image velocimetry were carried out on flapping hawkmoth-like wings in a water tank. Wing thickness was employed as a design variable for the wing flexi- bility distributions. Abrupt flap-down and phase delay in flexible wings influenced the behaviors of the Leading-Edge Vortex （LEV） and Trailing-Edge Vortex （TEV）, generated by the previous stroke. While the rigid wing exhibited a detached LEV at the end of the stroke, wing with specific flexibilities obtained attached LEVs. The attached LEVs induced a relatively rapid flow toward the wing surface as a result of encountering the TEV, and the flow caused a higher lift peak. On the other hand, the wings with larger wing deformations generated distinctive changes in LEV and TEV behaviors. The flap-down helped the TEV form closer to the wing surface, and it thus caused a downwash rather than wing-wake interaction. Furthermore, the most flexible wing had a newly-formed pair of LEVs above the wing during the wing reversal, thereby being not able to generate the wing-wake interaction. These results help to understand the different vortex structures generated by flexible wings during the wing reversal and the corresponding effects of wing-wake interaction.

关键词： hovering flight flexible hawkmoth wings wing-wake interaction Digital Particle Image Velocimetry (DPIV)

New fossil mayflies （Insecta： Ephemeroptera） from the Middle Jurassic of Daohugou, Inner Mongolia, China

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Insect Science 2008年第2期15卷 193-198页

作者： Jian-dong Huang dong Ren Nina D. Sinitshenkova chung-Kun Shih College of Life Science Capital Normal University Beijing China Palaeontological Institute of the Russian Academy of Sciences MoscowRussia

Abstract Jurassonurus amoenus, a new genus and species of Siphlonuridae s. I. is described from the Middle Jurassic Jiulongshan Formation of the Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China. The new species is estab- lished by more than 20 imago and subimago specimens in relatively good condition. Detailed description and illustration of the specimens along with a review of fossil Siphlonuridae s. I. are given. Comparing with two known dominant nymph species Fuyous gregarious Zhang and Kluge, 2007 and Shantous lacustri Zhang and Kluge, 2007 from the same locality, we could not find any relationship among them. The new species is another dominant species in Daohugou beds.

关键词： new genus new species Ephemeroptera Siphlonuridae fossil Daohugou,Middle Jurassic China

Cryptanalysis of the obfuscated round boundary technique for whitebox cryptography

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Science China(Information Sciences) 2020年第3期63卷 257-265页

作者： Yongjin YEOM dong-Chan KIM chung Hun BAEK Junbum SHIN Department of Information Security Cryptology and Mathematics Kookmin University Samsung Research Samsung Electronics

Dear editor,The security of cryptographic techniques heavily relies on the confidentiality of the key, and everything except keys can be made open to public without affecting security. When working with cryptographic services, we must protect the keys from a variety of attackers, including eavesdroppers and malware. A whitebox adversary is an attacker

关键词： II Cryptanalysis of the obfuscated round boundary technique for whitebox cryptography

Visual quality assessment after presbyopic laser in-situ keratomileusis

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 462-469页

作者： dong Hui Lim Eui-Sang chung Myoung Joon Kim Tae-Young chung Department of Ophthalmology Samsung Medical Center Sungkyunkwan University School of Medicine Department of Preventive Medicine Graduate School the Catholic University of Korea Department of Ophthalmology University of Ulsan College of MedicineAsan Medical Center

AIM： To assess visual quality after presbyopia correction using an aspheric ablation profile and a micro-monovision protocol. METHODS： This is a retrospective interventional study. Fifty-four eyes of 27 patients （mean age, 50.2±7.5y） who underwent presbyopia correction with an aspheric micro-monovision protocol were enrolled. The values of modulation transfer function （MTF） cutoff frequency, Strehl ratio, objective scattering index （OSI） and accommodation range were quantitatively assessed using the HD analyzer. Preoperative and postoperative contrast sensitivity （CS） at far （2.5 m） and near （40 cm） distance and higher-order aberrations （HOAs） were analyzed. Subjective visual satisfaction was evaluated by self-reported questionnaire regarding optical visual symptoms. RESULTS： One year after presbyopia correction, no significant differences were found in the MTF cutoff frequency, Strehl ratio and OSI, however, the lID analyzer accommodation range significantly differed postoperatively （P=0.004）. Postoperative CS at 12 and 18 cpd at near showed statistically significant improvement （P=0.020 and 0.008, respectively）. Visual performance by self-reported questionnaire revealed satisfactory results in terms of subjective visual quality improvement. CONCLUSION： Objective optical quality parameters show good visual outcomes. Subjective visual quality assessed by self-reported questionnaire in the presbyopia correction group show satisfactory results.

关键词： presbyopia correction laser blended vision visual quality LASIK