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Development of practical postprocessor for 5-axis machine tool with non-orthogonal rotary axes

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Journal of Central South University 2011年第1期18卷 159-164页

作者： JUNG Hyoun-Chul HWANG Jong-Dae park ki-beom JUNG Yoon-Gyo School of Mechatronics Changwon National University

In order to develop a practical postprocessor for 5-axis machine tool,the general equations of numerically controlled(NC) data for 5-axis configurations with non-orthogonal rotary axes were exactly expressed by the inverse kinematics,and a windows-based postprocessor written with Visual Basic was developed according to the proposed *** developed postprocessor is a general system suitable for all kinds of 5-axis machines with orthogonal and non-orthogonal rotary *** implementation of the developed postprocessor and verification by a cutting simulation and machining experiment,the effectiveness of the proposed algorithm is *** is improved by allowing exchange of data formats such as rotational total center position(RTCP) controlled NC data,vector post NC data,and program object file(POF) cutter location(CL) data,and convenience is increased by adding the function of work-piece origin ***,a practical post-processor for 5-axis machining is developed.

关键词： post-processor 5-axis machining non-orthogonal rotary axes numerically controlled (NC) data CL data

Content Caching Algorithms in Drone-Aided Ad Hoc Networks

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Computers, Materials & Continua 2024年第12期81卷 4727-4742页

作者： Yong beom park Jian kim beom Kyu Suh Ismatov Akobir ki-Il kim Department of Computer Science and Engineering Chungnam National UniversityDaejeon34134Republic of Korea

Content delivery networks(CDNs)lead to fast content distribution through content caching at specific CDN servers near end ***,existing CDNs based on infrastructure cannot be employed in special cases,such as military ***,a temporary CDN without an existing infrastructure is *** achieve this goal,we introduce a new CDN for drone-aided ad hoc networks,whereby multiple drones form ad hoc networks and quickly store specific content according to new caching *** the typical CDN server,the content-caching algorithm in the proposed architecture considers the limited storage capacity of the *** present three content distribution algorithms that consider the constraints and mobility of *** main contribution of content caching for drone-aided ad hoc networks is to keep partial segments rather than whole content as well as move the drone near to area with a high volume of *** proposed scheme is evaluated to demonstrate its feasibility in terms of content acquisition time and utilization in several practical scenarios through ***,acquisition time in CDN to support drone movement is improved by approximately 50%and 40%rather than one in the proposed naive greedy approach as a function of content request interval and size,respectively.

关键词： Content delivery networks content caching unmanned aerial networks Ad hoc networks partial segment duplicated contents drone

Optimization of Pyrolysis Properties using TGA and Cone Calorimeter Test

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Journal of Thermal Science 2013年第2期22卷 168-173页

作者： Won-Hee park Kyung-beom Yoon Eco-Transport Systems Research Division Korea Railroad Research Institute Department of Mechanical Engineering Chung-Ang University

The present paper describes an optimization work to obtain the properties related to a pyrolysis process in the solid material such as density, specific heat, conductivity of virgin and char, heat of pyrolysis and kinetic parameters used for deciding pyrolysis rate. A repulsive particle swarm optimization algorithm is used to obtain the pyrolysis-related properties. In the previous study all properties obtained only using a cone calorimeter but in this paper both the cone calorimeter and thermo gravimetric analysis (TGA) are used for precisely optimizing the pyrolysis properties. In the TGA test a very small mass is heated up and conduction and heat capacity in the specimen is negligible so kinetic parameters can first be optimized. Other pyrolysis-related properties such as virgin/char specific heat and conductivity and char density are also optimized in the cone calorimeter test with the already decided parameters in the TGA test.

关键词： Pyrolysis properties Thermogravimetric analysis Cone calorimeter Repulsive particle swarmoptimization

Inverse Problem of Flame Surface Properties of Wood using a Repulsive Particle Swarm Optimization Algorithm

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Journal of Thermal Science 2015年第2期24卷 173-178页

作者： Kyung-beom Yoon Won-Hee park Korea Conformity Laboratories 199Gasan-digital 1-roGeumcheon-guSeoul 153-803Korea Korea Railroad Research Institute 176 Cheoldobangmulgwan-roUiwang-siGyeonggi-do 437-757Korea Korea University of Science and Technology (UST) 217 Gajeong-roYuseong-guDaejeon 305-350 Korea

The convective heat transfer coefficient and surface emissivity before and after flame occurrence on a wood specimen surface and the flame heat flux were estimated using the repulsive particle swarm optimization algorithm and cone heater test results. The cone heater specified in the ISO 5660 standards was used, and six cone heater heat fluxes were tested. Preservative-treated Douglas fir 21 mm in thickness was used as the wood specimen in the tests. This study confirmed that the surface temperature of the specimen, which was calculated using the convective heat transfer coefficient, surface emissivity and flame heat flux on the wood specimen by a repulsive particle swarm optimization algorithm, was consistent with the measured temperature. Considering the measurement errors in the surface temperature of the specimen, the applicability of the optimization method considered in this study was evaluated.

关键词： Repulsive particle swarm optimization Cone calorimeter Flame heat flux Flame surface properties

Construction of random sheared fosmid library from Chinese cabbage and its use for Brassica rapa genome sequencing project

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Journal of Genetics and Genomics 2011年第1期38卷 47-53页

作者： Tae-Ho park beom-Seok park Jin-A kim Joon ki Hong Mina Jin Young-Joo Seol Jeong-Hwan Mun Genomics and Functional Bio-Material Division National Academy of Agricultural ScienceRural Development Administration The Department of Horticultural Science Daegu University

As a part of the Multinational Genome Sequencing Project of Brassica rapa, linkage group R9 and R3 were sequenced using a bacterial artificial chromosome （BAC） by BAC strategy. The current physical contigs are expected to cover approximately 90% euchromatins of both chromosomes. As the project progresses, BAC selection for sequence extension becomes more limited because BAC libraries are restriction enzyme-specific. To support the project, a random sheared fosmid library was constructed. The library consists of 97536 clones with average insert size of approximately 40 kb corresponding to seven genome equivalents, assuming a Chinese cabbage genome size of 550 Mb. The library was screened with primers designed at the end of sequences of nine points of scaffold gaps where BAC clones cannot be selected to extend the physical contigs. The selected positive clones were end-sequenced to check the overlap between the fosmid clones and the adjacent BAC clones. Nine fosmid clones were selected and fully sequenced. The sequences revealed two completed gap filling and seven sequence extensions, which can be used for further selection of BAC clones confirming that the fosmid library will facilitate the sequence completion of B. rapa.

关键词： Brassica rapa Chinese cabbage Fosmid library Genome sequencing Physical contig

Anatomy of the anterolateral ligament of the knee joint

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World Journal of Clinical Cases 2022年第21期10卷 7215-7223页

作者： Jun-Gu park Seung-beom Han Hye Chang Rhim Ok Hee Jeon ki-Mo Jang Department of Orthopaedic Surgery Anam HospitalKorea University College of MedicineSeoul 02841South Korea rtment of Biomedical Sciences Korea University College of MedicineSeoul 02841South Korea

Despite remarkable improvements in clinical outcomes after anterior cruciate ligament reconstruction,the residual rotational instability of knee joints remains a major *** anterolateral ligament(ALL)has recently gained attention as a distinct ligamentous structure on the anterolateral aspect of the knee *** studies investigated the anatomy,function,and biomechanics of ALL to establish its potential role as a stabilizer for anterolateral rotational ***,controversies regarding its existence,prevalence,and femoral and tibial insertions need to be *** to a recent consensus,ALL exists as a distinct ligamentous structure on the anterolateral aspect of the knee joint,with some anatomic *** aim of this article was to review the updated anatomy of ALL and present the most accepted findings among the existing ***,ALL originates slightly proximal and posterior to the lateral epicondyle of the distal femur and has an anteroinferior course toward the tibial insertion between the tip of the fibular head and Gerdy’s tubercle below the lateral tibial plateau.

关键词： Knee joint Anatomy Anterolateral ligament Anterior cruciate ligament Anterolateral rotational instability Anterolateral ligament reconstruction

Friction stir welding of 5052 aluminum alloy plates

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中国有色金属学会会刊：英文版 2009年第B9期19卷 23-27页

作者： Yong-Jai KWON Seong-beom SHIM Dong-Hwan park School of Materials Science and Engineering University of Ulsan Institute of E-Vehicle Technology University of Ulsan

Friction stir welding between 5052 aluminum alloy plates with a thickness of 2 mm was performed. The tool for welding was rotated at speeds ranging from 500 to 3000 r/min under a constant traverse speed of 100 mm/min. The results show that at all tool rotation speeds, defect-free welds are successfully obtained. Especially at 1000, 2000 and 3000 r/min, the welds exhibit very smooth surface morphologies. At 500, 1000, and 2000 r/min, onion ring structure is clearly observed in the friction-stir-welded zone (SZ). In addition, the onion ring structure region becomes wider as the tool rotation speed is increased. The gain size in the SZ is smaller than that in the base metal, and is decreased with a decrease of the tool rotation speed. In all tool rotation speeds, the SZ exhibits higher average hardness than the base metal. Especially at 500 r/min, the average hardness of the SZ reaches a level about 33% greater than that of the base metal. At 500, 1 000 and 2 000 r/min, the tensile strength of the friction stir welded (FSWed) plates is similar to that of the base metal (about 204 MPa). The elongation of the FSWed plates is lower than that of the base metal (about 22%). However, it is noticeable that the maximum elongation of about 21% is obtained at 1 000 r/min.

关键词：搅拌摩擦焊接铝合金板旋转速度焊接工具表面形貌环形结构抗拉强度伸长率

Spontaneous rupture of hepatic metastasis from a thymoma: A case report

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World Journal of Gastroenterology 2016年第44期22卷 9860-9864页

作者： Ho Jae kim Yong Eun park Min Seo ki Se Ju Lee Seung Hun beom Dai Hoon Han Young Nyun park Jun Yong park Department of Internal Medicine Yonsei University College of Medicine Department of Surgery Yonsei University College of Medicine Department of Pathology Yonsei University College of Medicine

Bleeding resulting from spontaneous rupture of the liver is an infrequent but potentially life threatening complication that may be associated with an underlying liver disease. A hepatocellular carcinoma or hepatic adenoma is frequently reported is such cases. However, hemoperitoneum resulting from a hepatic metastatic thymoma is extremely rare. Here, we present a case of a 62-year-old man with hypovolemic shock induced by ruptured hepatic metastasis from a thymoma. At the first hospital admission, the patient had a 45-mm anterior mediastinal mass that was eventually diagnosed as a type A thymoma. The mass was excised, and the patient was disease-free for 6 years. He experienced sudden-onset right upper quadrant pain and was again admitted to our hospital. We noted large hemoperitoneum with a 10-cm encapsulated mass in S5/8 and a 2.3-cm nodular lesion in the right upper quadrant of the abdomen. He was diagnosed with hepatic metastasis from the thymoma, and he underwent chemotherapy and surgical excision.

关键词： Spontaneous rupture Hemoperitoneum Transarterial chemoembolization Hepatic metastasis Thymoma

Submergence promotes auxin-induced callus formation through ethylene-mediated post-transcriptional control of auxin receptors

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Molecular Plant 2022年第12期15卷 1947-1961页

作者： Seung Yong Shin Yuri Choi Sang-Gyu kim Su-Jin park Ji-Sun park ki-beom Moon Hyun-Soon kim Jae Heung Jeon Hye Sun Cho Hyo-Jun Lee Plant Systems Engineering Research Center Korea Research Institute of Bioscience and BiotechnologyDaejeon 34141Korea Department of Functional Genomics KRIBB School of BioscienceUniversity of Science and TechnologyDaejeon 34113Korea Department of Biological Sciences Korea Advanced Institute of Science and TechnologyDaejeon 34141Korea Department of Biosystems and Bioengineering KRIBB School of BiotechnologyUniversity of Science and TechnologyDaejeon 34113Korea Department of Biological Sciences Sungkyunkwan UniversitySuwon 16419Korea

Plant cells in damaged tissue can be reprogrammed to acquire pluripotency and induce callus ***,in the aboveground organs of many species,somatic cells that are distal to the wound site become less sensitive to auxin-induced callus formation,suggesting the existence of repressive regulatory mechanisms that are largely *** we reveal that submergence-induced ethylene signals promote callus formation by releasing post-transcriptional silencing of auxin receptor transcripts in non-wounded *** determined that short-term submergence of intact seedlings induces auxin-mediated cell dedifferentiation across the entirety of Arabidopsis thaliana *** constitutive triple response 1-1(ctr1-1)mutation induced callus formation in explants without submergence,suggesting that ethylene facilitates cell *** show that ETHYLENE-INSENSITIVE 2(EIN2)post-transcriptionally regulates the abundance of transcripts for auxin receptor genes by facilitating microRNA393 ***-induced calli in non-wounded regions were suitable for shoot regeneration,similar to those near the wound *** also observed submergence-promoted callus formation in Chinese cabbage(Brassica rapa),indicating that this may be a conserved mechanism in other *** study identifies previously unknown regulatory mechanisms by which ethylene promotes cell dedifferentiation and provides a new approach for boosting callus induction efficiency in shoot explants.

关键词： cell dedifferentiation auxin signaling ethylene callus formation EIN2