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Microsystems & Nanoengineering 2023年第2期9卷 321-332页

作者： Jihun lee Hongyun So Department of Mechanical Engineering Hanyang UniversitySeoul 04763South Korea institute of Nano Science and Technology Hanyang UniversitySeoul 04763South Korea

In this study,a flexible pressure sensor is fabricated using polydimethylsiloxane(PDMS)with a concentric circle pattern(CCP)obtained through a fused deposition modeling(FDM)-type three-dimensional(3D)printer and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)as the active *** layer-by-layer additive manufacturing,the CCP surface is generated from a thin cone model with a rough surface by the FDM-type 3D printer.A novel compression method is employed to convert the cone shape into a planar microstructure above the glass transition temperature of a polylactic acid(PLA)*** endow the CCP surface with conductivity,PDMS is used to replicate the compressed PLA,and PEDOT:PSS is coated by *** size of the CCP is controlled by changing the printing layer height(PLH),which is one of the 3D printing *** sensitivity increases as the PLH increases,and the pressure sensor with a 0.16 mm PLH exhibits outstanding sensitivity(160 kPa^(-1)),corresponding to a linear pressure range of 0-0.577 kPa with a good linearity of R^(2)=0.978,compared to other *** pressure sensor exhibits stable and repeatable operation under various pressures and durability under 6.56 kPa for 4000 ***,monitoring of various health signals such as those for the wrist pulse,swallowing,and pronunciation of words is demonstrated as an *** results support the simple fabrication of a highly sensitive,flexible pressure sensor for human health monitoring.

关键词： printing pattern PDMS

The impact of reporting frequency on the information quality of share price： evidence from Chinese state-owned enterprises

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Frontiers of Business Research in China 2018年第2期12卷 83-100页

作者： Yin Toa lee Wilson H. S. Tong Ernst & Young 22/F CITIC Tower 1 Tim Mei Avenue Central Hong Kong Hong Kong

As a major global exchange, the Stock Exchange of Hong Kong （SEHK） only requires semi-annual reporting whereas other major exchanges including the ones in Chinese mainland require quarterly reporting. We argue against the traditional view that higher reporting frequency is necessarily more beneficial. The decision on reporting frequency depends on how the information is being processed by the recipient traders and the results are not obvious. Using a sample of Chinese companies dual- listed in both China A share market and SEHK （AH shares） as the experimental group and mainland＇s companies listed on SEHK （H shares） only as the control group, we apply the difference-in-difference （DID） method to investigate the impacts of reporting frequency on stock information quality. The results suggest that after China A share market require quarterly financial reporting for all listed companies in 2002, the information asymmetry of the H tranche of AH stocks increases. Different from prior studies, the results suggest a negative association between stock information quality and financial reporting frequency. We argue that the increased information asymmetry in the H tranche is caused by the noise spilled over from the A tranche. We conduct multivariable GARCH tests and find evidence supporting this conjecture.

关键词： Mainland market Hong Kong market Dual-listing Reporting frequency,Information asymmetry Volatility spillover effects

FIDS:Filtering-Based Intrusion Detection System for In-Vehicle CAN

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Intelligent Automation & Soft Computing 2023年第9期37卷 2941-2954页

作者： Seungmin lee Hyunghoon Kim Haehyun Cho Hyo Jin Jo Department of Software Soongsil UniversitySeoul06978Korea

Modern vehicles are equipped with multiple Electronic Control Units(ECUs)that support various convenient driving functions,such as the Advanced Driver Assistance System(ADAS).To enable communication between these ECUs,the Controller Area Network(CAN)protocol is widely ***,since CAN lacks any security technologies,it is vulnerable to cyber *** address this,researchers have conducted studies on machine learning-based intrusion detection systems(IDSs)for ***,most existing IDSs still have non-negligible detection *** this paper,we pro-pose a new filtering-based intrusion detection system(FIDS)to minimize the detection errors of machine learning-based *** uses a whitelist and a blacklist created from CAN *** whitelist stores the cryptographic hash value of normal packet sequences to correct false positives(FP),while the blacklist corrects false negatives(FN)based on transmission intervals and identifiers of CAN *** evaluated the performance of the proposed FIDS by implementing a machine learning-based IDS and applying FIDS to *** conducted the evaluation using two CAN attack datasets provided by the Hacking and Countermeasure Research Lab(HCRL),which confirmed that FIDS can effectively reduce the FP and FN of the existing IDS.

关键词： Controller area network machine learning intrusion detection system automotive security

The Study on the Mechanical Properties of Optical Fiber With Long-Term Time Aging

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光学学报 2003年第S1期23卷 100-101页

作者： Sung Koog Oh Young Seok Kim Jae Ho lee R&D Group 1 Fiberoptics Division Telecommunication Network Business Samsung Electronics Co.Ltd.#94-1 Imsoo-Dong Gumi-City Kyung-Buk KoreaR&D Group 1 Fiberoptics Division Telecommunication Network Business Samsung Electronics Co.Ltd.#94-1 Imsoo-Dong Gumi-City Kyung-Buk KoreaR&D Group 1 Fiberoptics Division Telecommunication Network Business Samsung Electronics Co.Ltd.#94-1 Imsoo-Dong Gumi-City Kyung-Buk Korea

The fiber properties depending on the coating thickness and long-term time aging were investigated. The coating strip forces of optical fiber were strongly increased with secondary coating thickness. But it did not change with time aging up to 90 days. The tensile strength and stress corrosion parameters of coated fiber were increased with time aging also but the increasing rate was quite different depending on the coating

关键词： of with in were The Study on the Mechanical Properties of Optical Fiber With Long-Term Time Aging on

Structure-activity relationship of lysophosphatidylcholines in HL-60 human leukemia cells

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Acta Pharmacologica Sinica 2004年第11期 137-140页

作者： Eun-hee lee,Jee H JUNG,Dong-soon IM Laboratories of Pharmacology and Marine Natural Product Laboratories of Pharmacology and Marine Natural Product Laboratories of Pharmacology and Marine Natural Product College of Pharmacy Pusan National University Busan 609-735 Korea College of Pharmacy Pusan National University Busan 609-735 Korea College of Pharmacy Pusan National University Busan 609-735 Korea

AIM: To explore the structure-activity relationship of lysophosphatidylcholine (LPC) and lysolipid molecules from a marine sponge and ladybirds. METHODS: We tested three synthetic LPCs and four natural lysolipids on Ca2+ mobilization in HL-60 human leukemia cells. RESULTS: We observed lysolipid-mediated Ca2+ mobilization. The activity was the same in both ester- and ether-linked lysolipids, and introduction of a double bond or methoxy group on the alkyl chain did not significantly modulate the activity. However, replacement of trimethylammonium moiety in the choline structure with ammonium moiety reduced the activity. Furthermore, change of the alkyl chain length influenced the Ca2+ response. CONCLUSION: LPC-induced Ca2+ mobilization might be dependent on the length of alkyl chain and the presence of choline moiety in HL-60 leukemia cells.

关键词： lysophosphatidylcholines leukemia calcium signaling structure-activity relationship platelet activating factor

Prediction of performance and evaluation of flexible pavement rehabilitation strategies

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第2期4卷 178-184页

作者： Kang-Won Wayne lee Kathleen Wilson Syed Amir Hassan Department of Civil and Environmental Engineering University of Rhode Island Kingston R1 02881 USA Rhode Island Department of Transportation Prouid-ence RI 02903 USA

Five test sections with different additives and strategies were established to rehabilitate a State-maintained highway more effectively in Rhode Island （RI）： control, calcium chloride, asphalt emulsion, Portland cement and geogrid. Resilient moduli of subgrade soils and subbase materials before and after full depth rehabilitation were employed as input pa- rameters to predict the performance of pavement structures using AASHTOWare Pave- ment ME Design （Pavement ME） software in terms of rutting, cracking and roughness. It was attempted to use Level i input （which includes traffic full spectrum data, climate data and structural layer properties） for Pavement ME. Traffic data was obtained from a Weigh- in-Motion （WIM} instrument and Providence station was used for collecting climatic data. Volumetric properties, dynamic modulus and creep compliance were used as input pa- rameters for 19 mm （0.75 in.} warm mix asphalt （WMA） base and 12.S mm （0.5 in.） WMA surface layer. The results indicated that all test sections observed AC top-down （longitu- dinal） cracking except Portland cement section which passed for all criteria. The order in terms of performance （best to worst） for all test sections by Pavement ME was Portland cement, calcium chloride, control, geogrid, and asphalt emulsion. It was also observed that all test sections passed for both bottom up and top down fatigue cracking by increasing thickness of either of the two top asphalt layers. Test sections with five different base/ subbase materials were evaluated in last two years through visual condition survey and measurements of deflection and roughness to confirm the prediction, but there was no serious distress and roughness. Thus these experiments allowed selecting the best reha- bilitation/reconstruction techniques for the particular and/or similar highway, and a framework was formulated to select an optimal technique and/or strategy for future rehabilitation/reconstruction projects. Finally, guidelines for lo

关键词： Full depth rehabilitation Resilient modulus AASHTOWare pavement ME design Surface distress

Comparative Study on Shearing Edge Quality Influence of the Change of Tool Geometry in Fine-Blanking for Non-homogeneous Materials

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厦门大学学报（自然科学版） 2002年第S1期41卷 117-118页

作者： Y C Leung L C Chan T C lee Department of Industrial and Systems Engineering the Hong Kong Polytechnic UniversityDepartment of Industrial and Systems Engineering the Hong Kong Polytechnic UniversityDepartment of Industrial and Systems Engineering the Hong Kong Polytechnic University Hong Kong ChinaHong Kong ChinaHong Kong China

Excellent quality of shearing edge implies that a s mo oth cutting edge without tearing will be observed on the whole edge surface. Thi s is one of the most significant features of the Fine-blanking process. To achi eve such a superb blanking edge quality in fine-blanking, there actually involv es quite a large number of factors, such as blanking speed, processing material, product shape, lubrication and tool geometry, to be considered simultaneously d uring the operation. Nevertheless, the thorough investigations on different effe cts of those critical factors for different kinds of popular and applicable mate rial are rare and limited. Thus, the objective of this paper is mainly focused o n the study of the quality influence of tool geometry change in fine-blanking f or non-homogeneous materials. However, the most obvious change of the tool geo metry during the operation will be the essential variation of the nose radius of the punch. This is because the nose radius usually seriously deteriorates with the increasing service period in mass production which eventually causes the ent irely lose of the specific features of the fine-blanking process. Therefore, a tailor-made experimental study was carried out to investigate the relationship between the punch nose radius and the shearing edge quality, such as blanked edg e finish, burr height and die-roll height, during fine-blanking for different types of material. Five punches with each specified nose radius (Rp), 0.00 mm, 0.25 mm, 0.50 mm, 0.75 mm and 1.00 mm, and four kinds of blanking material ( Mil d steel SS400, Stainless steel AISI316L, Copper alloy UNSC16200 and Aluminium al loy AA6063 ) were employed throughout the study. Subsequently, features of the s heared edge surfaces and data of each experiment were observed and captured for further analysis in this research. Consequently, findings show that an increase of punch nose radius would produce a higher percentage of fracture of blanked ed ge and increase the

关键词： fine-blanking tool geometry shearing edge qual ity

Sol-gel synthesis and characterization of hydroxyapatite nanorods

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Particuology 2009年第6期7卷 466-470页

作者： Sanosh Kunjalukkal Padmanabhan Avinash Balakrishnan Min-Cheol Chu Yong Jin lee Taik Nam Kim Seong-Jai Cho Department of Information and Electronic Materials Engineering College of EngineeringPaichai UniversityDaejeon 302-735Republic of Korea Division of Metrology for Emerging Technology Korea Research Institute of Standards and Science1 Doryong-DongYuseong-GuDaejeon 305-340Republic of Korea Division of Advanced Technology Korea Research Institute of Standards and ScienceDaejeon 305-340Republic of Korea

In the present study hydroxyapatite （HA） nano-hexagonal rods with 70-90 nm diameter and 400-500 nm length are synthesized using a simple sol-gel route with calcium nitrate and potassium dihydrogenphosphate as calcium and phosphorus precursors respectively. Deionized water was used as a diluting media for HA sol preparation and ammonia was used to adjust the pH = 9. After aging, the HA gel was dried at 60 ℃ and calcined at different temperatures ranging from 300 to 700 ℃. The dried and calcined powders were characterized for phase composition using X-ray diffractrometry, elemental dispersive X-ray and Fourier transform infrared spectroscopy. Rietveld analysis showed the calcined HA powders of high purity with a hexagonal unit cell structure. Calcination yielded HA nanopowders of increased particle size and crystallinity with increase in temperature. The particle size and morphology was studied using transmission electron microscopy. The aspect ratio （length to diameter ratio） of HA nanorods was measured to be between 6 and 7.

关键词： Hydroxyapatite Nanorods Sol-gel Particle size Morphology

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低失重烧结钕铁硼磁体的研究进展

稀有金属 2010年第1期34卷 145-150页

作者：丁勇陈仁杰闫阿儒李东中国科学院宁波材料技术与工程研究所浙江省磁性材料及其应用技术重点实验室浙江宁波315201

烧结钕铁硼永磁材料被发明以来,以其优越的磁性能得到了广泛的应用,目前成为永磁产业的支柱。但是其耐腐蚀性能差,大大限制了其使用范围。因此,近20多年来如何改善其抗腐蚀性能成为烧结钕铁硼材料生产和使用的重要问题。总结了烧结钕铁... 详细信息

烧结钕铁硼永磁材料被发明以来,以其优越的磁性能得到了广泛的应用,目前成为永磁产业的支柱。但是其耐腐蚀性能差,大大限制了其使用范围。因此,近20多年来如何改善其抗腐蚀性能成为烧结钕铁硼材料生产和使用的重要问题。总结了烧结钕铁硼腐蚀失重的机制,制备低失重烧结钕铁硼的方法和工艺,对如何提高烧结钕铁硼磁体的耐腐蚀性,降低腐蚀失重进行了综述。从磁体成分设计和微观结构方面总结了几条提高烧结钕铁硼磁体耐蚀性的原则,其关键是对晶界相的成分和微观结构进行合理的控制。

关键词：烧结钕铁硼耐蚀性低失重

Hsa-miR-637 inhibits human hepatocyte proliferation by targeting Med1-interacting proteins

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Liver Research 2021年第2期5卷 88-96页

作者： Jing Liu Jianyun Zhu Xiaohong Zhang yuzhi Jia Xuejun lee Zhiliang Gao Department of Infectious Diseases The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Pathology Northwestern University Feinberg School of MedicineChicagoILUSA

Background:Recent studies have shown that mediator complex subunit 1(Med1)can significantly affect hepatocyte proliferation and *** as a tumor suppressor,microRNA-637(hsa-miR-637)can inhibit the growth of hepatocarcinoma cells and further induce cell ***,the function of hsa-miR-637 and its target genes during liver regeneration remains to be ***:This study used co-immunoprecipitation(Co-IP)assay,transfection,luciferase reporter assay,functional assay by cell counting kit-8(CCK-8),Annexin V-FITC/propidium iodide apoptosis assay,and quantitative polymerase chain reaction analysis of chromatin immunoprecipitation(ChIP)for ***:Hsa-miR-637 has been suggested to suppress the expression of two Med1-interacting nuclear receptors,identified as the peroxisome proliferator-activated receptor alpha(PPARA)and thyroid hormone receptor alpha(THRA)at the transcriptional and translational levels in the human liver HL-7702 cell *** interaction between Med1 and PPARA/THRA in HL-7702 cells was then *** transcriptional repression of hsa-miR-637 on PPARA and THRA was also ***,hsamiR-637 has been determined to suppress the proliferation of HL-7702 ***,cell cycle arrest of HL-7702 cells was induced by transfection of hsa-miR-637 at the S phase,but its apoptosis ***,PPARA was indicated to directly bind to the promoter of some transcription factors,like bcatenin,mouse double minute 2(MDM2),and ***:This study has confirmed that hsa-miR-637 plays an antiproliferative role during liver regeneration,which may contribute in understanding the regenerative process of the liver.

关键词： Liver regeneration Hsa-miR-637 Peroxisome proliferator-activated receptor alpha(PPARA) Thyroid hormone receptor alpha(THRA) Mediator complex subunit 1(Med1)