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Journal of Traffic and Transportation Engineering(English Edition) 2019年第6期6卷 589-597页

作者： Hyun Hwan Kim Mithil Mazumder Soon-Jae lee Moon-sup lee Department of Engineering Technology Texas State UniversitySan MarcosTX 78666USA Korea Institute of Civil Engineering and Building Technology Gyeonggi 411-712South Korea

The study presents an experimental evaluation of performance properties of two different production processes of warm rubberized *** types of rubberized binder were produced through dry process and wet process and two of the available wax additives were added into the rubberized binders(i.e.,LEADCAP and Sasobit).Rubberized binders with wax additives were artificially short-term and long-term aged using the rolling thin film oven(RTFO) and pressure aging vessel(PAV) *** binder tests were carried out on the binders through the rotational viscometer(RV),the dynamic shear rheometer(DSR),and the bending beam rheometer(BBR).In general,the results of this study indicated that(1) the viscosity properties have been found to be similar between dry and wet processes,(2) the rubberized binders manufactured by wet process were observed to have the higher rutting resistance than those by dry process,(3) the wet process resulted in better performance in the fatigue cracking test than the dry process,and(4) the blending method was found to have little influence of stiffness properties.

关键词： Rubberized binder Dry process Wet process Viscosity Rutting Fatigue cracking

Gost effectiveness of crack treatment methods:A field study

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第6期6卷 598-607页

作者： Mithil Mazumder Hyun Hwan Kim Soon-Jae lee Moon-sup lee Materials Science Engineeringand Commercialization ProgramTexas State UniversitySan MarcosTX 78666USA Department of Engineering Technology Texas State UniversitySan MarcosTX 78666USA Korea Institute of Civil Engineering and Building Technology Gyeonggi-do 10223South Korea

In the United States,more than 94%highways are paved with asphalt materials and placing crack sealant materials has been a common pavement maintenance for *** sealing treatment includes the use of a router to create a reservoir on the intended cracks whereas crack filling is given without doing any modification to the crack *** the initial cost of crack sealing is higher,it is expected to have a longer service period compared to crack *** is little research on comparison of short and long term cost effectiveness between these two treatments using the real field cost data *** this study four test sites in Texas were treated with crack filling and sealing using the same sealant material and finishing *** effectiveness of both treatments was measured in terms of initial,annual average and life cycle cost based on the cost inputs during *** general,the results of this study indicated that(1)on an average approximately 45%initial cost increase was estimated with the two routing configurations of crack sealing;(2)material and labor cost is found to have the most significant effect on the higher initial cost of crack sealing compared to other associated costs;(3)annual average and life cycle costs have shown that crack sealing is more cost effective pavement maintenance compared to crack filling over a long period of time;(4)agency cost is observed to be reduced by approximately 24%with crack sealing treatment based on the35 year analysis period.

关键词： Crack sealing Crack filling Initial cost Annual average cost Life cycle cost

Unusual case of emphysematous cystitis mimicking intestinal perforation:A case report

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World Journal of Clinical Cases 2023年第28期11卷 6943-6948页

作者： Hye Yoon Kang Dae-sup lee Donghyoun lee Department of Surgery Samsung Medical CenterSeoul 06338South Korea Department of Emergency Medicine Pusan National University Yangsan HospitalYangsan 50612South Korea Department of Surgery Jeju National University HospitalJeju National University College of MedicineJeju 63241South Korea

BACKGROUND Emphysematous cystitis(EC)is a bladder condition commonly caused by gasgenerating bacterial *** that increase the risk for developing this condition include female gender,age≥60 years,and diabetes mellitus,glycosuria,and urinary *** symptoms of EC often lack specificity,making diagnostic imaging techniques crucial for accurate identification of the *** SUMMARY This report presents an unusual case of EC that mimicked intestinal *** it was initially challenging to differentiate between intestinal perforation and EC on admission,the patient managed to avoid unnecessary surgery and made a good recovery solely through antibiotic *** Successful treatment of the patient described herein highlights the importance of accurately diagnosing EC,which can be difficult to differentiate from intestinal perforation.

关键词： Emphysematous cystitis Intestinal Bowel Perforation Bladder Case report

Effect of bonding interface on delamination behavior of drawn Cu/Al bar clad material

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中国有色金属学会会刊：英文版 2012年第S3期22卷 645-649页

作者： Sangmok lee Min-Geun lee Sang-Pill lee Geun-Ahn lee Yong-Bae KIM Jong-sup lee Dong-Su BAE Advanced Forming Technology Center Korea Institute of Industrial Technology Department of Advanced Materials Engineering Dong-Eui University Department of Mechanical Engineering Dong-Eui University

Cu/Al bar clad material was fabricated by a drawing process and a subsequent heat *** these processes,intermetallic compounds have been formed at the interface of Cu/Al and have affected its bonding *** of Cu/Al interfaces were observed by OM,SEM and EDX Analyser in order to investigate the bonding properties of the *** to the microstructure a series of diffusion layers were observed at the interface and the thicknesses of diffusion layers have increased with aging time as a result of the diffusion *** interfaces were composed of 3-ply diffusion layers and their compositions were changed with aging time at 400 °*** compositional compounds were revealed to be η2,(θ+η2),(α+θ) intermetallic *** is evident from V-notch impact tests that the growth of the brittle diffusion layers with the increasing aging time directly influenced delamination distance between the Cu sleeve and the Al *** is suggested that the proper holding time at 400 °C for aging as post heat treatment of a drawn Cu/Al bar clad material would be within 1 h.

关键词： drawn Cu/Al bar clad material aging bonding interface intermetallic compound diffusion layer delamination

The influence of thermohaline fronts on chlorophyll a concentrations during spring and summer in the southeastern Yellow Sea

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Acta Oceanologica Sinica 2013年第9期32卷 82-90页

作者： JANG Pung-Guk lee Tong sup KANG Jung-Hoon SHIN Kyoungsoon Korea Institute of Ocean Science and Technology/South Sea Institute Department of Oceanography College of Natural SciencesPusan National University

A spatial and temporal variation in physiochemical parameters in the southeastern Yellow Sea （YS） is in- vestigated in the spring and summer of 2009 to 2011. Nutrient show a strong negative relationship with chlorophyll a （Chl a） concentration in spring, and the subsurface chlorophyll a maxima （SCM） layer was associated with the nitracline in summer. In summer, the SCM was usually found within or above the pyc- nocline and at the depths of shoals from the open sea to the coastal sea due to tidal and/or topographical fronts in the southernmost study area. High Chl a concentrations were found in the central southern YS, where the YS cold water layer expanded under the pycnocline and encountered water masses during spring and summer. After a typhoon in the summer of2011, Chl a concentration increased, especially in the central southern YS, where cold waters occurred below the pycnocline. The results suggest that the development of thermohaline fronts may play an important role in the growth and accumulation of phytoplankton biomass in the upper layer of the southeastern YS during spring and summer.

关键词： Yellow Sea Cold Water nutrient chorophyll a thermohaline front

A convenient synthesis of methyl 2-hydroxy-4-oxo-4-(substituted phenyl) butanoates from malic acid

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Chinese Chemical Letters 2009年第8期20卷 898-900页

作者： Yong Zhang M. NaseerA. Khan Ping Gong Yong sup lee School of Pharmaceutical Engineering Shenyang Pharmaceutical University 103 Wenhua Road Shenhe District Shenyang 110016 PR China kyung Hee East-West Pharmaceutical Research Institute and Department of Pharmaceutical Sciences College of Pharmacy KyungheeUniversity Seoul 130-701 Republic of Korea

A synthesis of methyl 2-hydroxy-4-oxo-4-（substituted phenyl）butanoates has been accomplished using Friedel-Crafts acylation of substituted benzenes with 2-acetoxybutanoyl chloride. The key feature of this strategy is that various 4-arylbutanoates can be obtained conveniently, which are important intermediates for the synthesis of biologically active compounds including ACE inhibitors.？2009 Yong sup lee. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 2-Hydroxy-4-oxo-4-phcnylbutanoatcs Malic acid Fricdel-Crafts reaction

Experimental investigation of friction coefficient in tube hydroforming

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 194-198页

作者： Hyae kyung YI Hong sup YIM Gun Yeop lee Sung Mun lee Gi Suk CHUNG Young-Hoon MOON Engineering Research Center for Net Shape and Die Manufacturing School of Mechanical Engineering Pusan National University Technical Research laboratories POSCO Jeonnam 545-090 Korea

The friction coefficient between tube and die in guide zone of tube hydroforming was obtained. In hydroforming, the tube is expanded by an internal pressure against the tool wall. By pushing the tube through tool, a friction force at the contact surface between the tube and the tool occurs. In guiding zone, the friction coefficients between tube and die can be estimated from the measured axial feeding forces. In expansion zone, the friction coefficients between tube and die can be evaluated from the measured geometries of expanded tubes and FE analysis.

关键词： tube hydroforming friction coefficient lubricant axial force internM pressure

Application of direct laser metal tooling for AISI H13 tool stee

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中国有色金属学会会刊：英文版 2009年第B09期19卷 284-287页

作者： Jae-Ho lee Jeong-Hwan JANG Byeong-Don JOO Hong-sup YIM Young-Hoon MOON School of Mechanical Engineering Pusan National University

In the die industry, it is commonly agreed that residual tool life can be successfully extended by timely repair of damaged surfaces. Traditionally, the main repair process is tungsten inert gas (TIG) welding, but a new process called direct laser metal tooling (DLMT) emerges. DLMT is a manual process, of which results depend on the materials of the powders and tools, the laser process and parameters. This technology is a direct-metal freeform fabrication technique in which a 200 W fiber laser is used. AISI H13 tool steel is a suitable material for die casting tools because of the high resistance to thermal fatigue and dimensional stability. In this research, AISI H13 tool steel was melted with metal powder by fiber laser. Before melting AISI H13, the powders were analyzed with XRF equipment. Then, hardness distribution of laser melted zone was investigated. The microstructure in laser melted zone was discussed. In order to identify the effect of particle size of powder on the melted zone, two types of particle sizes of powders were used. Experimental results show that the mold repair process using DLMT can be applied in the mold repair industry.

关键词：金属模具应用激光工具钢 H13 社会光纤激光器粉末材料修复过程

Characterization of recycled crumb rubber modified binders containing wax warm additives

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第3期5卷 197-206页

作者： Hyun Hwan Kim Mithil Mazumder Soon-Jae lee Moon-sup lee Department of Engineering Technology Texas State University San Marcos TX 78666 USA Materials Science Engineering and Commercialization Program Texas State University San Marcos TX 78666 USA Korea Institute of Civil Engineering and Building Technology Goyang-si Gyeonggi-do 10223 Republic of Korea

This paper addresses the laboratory experiment of performance properties of recycled CRM binders containing artificially aged CRM binders with wax additives. The warm CRM binders were produced using two wax additives （LEADCAP and Sasobit） and then shortterm and long-term aged using the rolling thin film oven （RTFO） and pressure aging vessel （PAV） procedures. The recycled CRM binders were aged through the RTFO and PAV pro- cedures. A set of superpave binder tests were carried out on the binders through the rotational viscometer, the dynamic shear rheometer （DSR）, and the bending beam rheometer （BBR）. In general, the results of this study indicated that （1） the addition of longterm aged （LTA） CRM binder can significantly increase the viscosity of the recycled CRM binders as expected, （2） the wax additives in recycled CRM binders were still effective to improve the viscosity and rutting properties even after experiencing the aging process, （3） the CRM binders containing wax additives showed the higher rutting resistance compared to the control CRM binders, （4） the recycled CRM binder containing wax additives was found to have less resistance to fatigue and low temperature cracking, （5） wax warm additives into the recycled CRM binders seemed to have a significant role for cracking properties, based upon their substantial amount.

关键词： CRM binder Wax additives Rotational viscosity Recycling Rutting