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Computer Modeling in Engineering & sciences 2024年第10期141卷 671-688页

作者： Youngho park su Jin shin sang Uk shin Electronics and Information Communications Research Center Pukyong National UniversityBusan48513Republic of Korea Department of Information security Graduate SchoolPukyong National UniversityBusan48513Republic of Korea Division of Computer Engineering Pukyong National UniversityBusan48513Republic of Korea

Data trading enables data owners and data requesters to sell and purchase *** the emergence of blockchain technology,research on blockchain-based data trading systems is receiving a lot of ***,to reduce the on-chain storage cost,a novel paradigm of blockchain and cloud fusion has been widely considered as a promising data trading ***,the fact that data can be used for commercial purposes will encourage users and organizations from various fields to participate in the data *** the data marketplace,it is a challenge how to trade the data securely outsourced to the external cloud in a way that restricts access to the data only to authorized users across multiple *** this paper,we propose a cross-domain bilateral access control protocol for blockchain-cloud based data trading *** consider a system model that consists of domain authorities,data senders,data receivers,a blockchain layer,and a cloud *** proposed protocol enables access control and source identification of the outsourced data by leveraging identity-based cryptographic *** the proposed protocol,the outsourced data of the sender is encrypted under the target receiver’s identity,and the cloud provider performs policy-match verification on the authorization tags of the sender and receiver generated by the identity-based signature ***,data trading can be achieved only if the identities of the data sender and receiver simultaneously meet the policies specified by each *** demonstrate efficiency,we evaluate the performance of the proposed protocol and compare it with existing studies.

关键词： Bilateral access control blockchain data sharing policy-match

Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn’s disease

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World Journal of stem Cells 2024年第3期16卷 257-266页

作者： Min Young park Yong sik Yoon Jae Ha park Jong Lyul Lee Chang sik Yu Division of Colon and Rectal surgery Department of SurgeryYonsei University College of MedicineSeoul 03722South Korea Division of Colon and Rectal surgery Department of SurgeryUniversity of Ulsan College of MedicineAsan Medical CenterSeoul 05505South Korea

BACKGROUND stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn’s disease(CD).Anti-tumor necrotic factor(TNF)therapy combined with drainage procedure is effective as ***,previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula *** This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn’s perianal fistula(CPF)closure rates after stem cell transplantation with and without anti-TNF therapy,and to identify the factors affecting CPF closure and *** The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were *** data were compared according to anti-TNF therapy and CPF *** A total of 65 patients were *** median age of females was 26 years(range:21-31)and that of males was 29(44.6%).The mean follow-up duration was 65.88±32.65 months,and complete closure was observed in 50(76.9%)*** closure rates were similar after stem cell transplantation with and without anti-TNF therapy(66.7%vs 81.6%at 3 year,P=0.098).The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture(P=0.027,0.002,and 0.008,respectively).Clinical factors such as complexity,number of fistulas,presence of concurrent abscess,and medication were not significant for *** cumulative 1-,2-,and 3-year closure rates were 66.2%,73.8%,and 75.4%,*** Anti-TNF therapy does not increase CPF closure rates in patients with stem cell ***,both refractory and non-refractory CPF have similar closure rates after additional anti-TNF *** tract length,proctitis,and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

关键词： Crohn’s disease Anus Fistula stem cell transplantation Tumor necrosis factor-alpha inhibitors Infliximab

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分子束外延高Mg掺杂GaN的发光特性

发光学报 1999年第2期20卷 148-151页

作者：宋航 park s H Kang T W Kim T W 中国科学院长春物理研究所

采用分子束外延技术在蓝宝石衬底上制备Ｍｇ掺杂的立方相ｐ－ＧａＮ，并对其不同温度下的光致发光光谱进行了研究．实验观察到高Ｍｇ掺杂ＧａＮ中施主受主对发光的反常温度行为．理论分析表明，高Ｍｇ掺杂ＧａＮ中施主受主对的发光受到... 详细信息

采用分子束外延技术在蓝宝石衬底上制备Ｍｇ掺杂的立方相ｐ－ＧａＮ，并对其不同温度下的光致发光光谱进行了研究．实验观察到高Ｍｇ掺杂ＧａＮ中施主受主对发光的反常温度行为．理论分析表明，高Ｍｇ掺杂ＧａＮ中施主受主对的发光受到陷阱与受主间竞争俘获非平衡空穴过程和空穴隧穿输运过程的影响．

关键词：光致发光隧穿效应分子束外延氮化镓掺镁

Prediction of chlorophyll-a in agricultural reservoirs of Korea using Particle swarm Optimization (PsO)

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Prediction of chlorophyll-a in agricultural reservoirs of Ko...

Azimuthal rotation-controlled nanoinscribing for continuous patterning of period-and shapetunable asymmetric nanogratings

第三世界生态高峰会

作者： Kwon Y.s. Bae M.J. Hwang s.J. park Y.s. Department of Biology.Kyung Hee University seou 130-701 Korea Department of Environicntal science Kon Kuk University seoul 143-701 Korea

Eutrophication in water systems can be evaluated via the estimate of chlorophyll-a which exists in the cell of phytoplankton in water systems *** prediction of chlorophyll-a based on environmental thctors can be used efficiently to manage water quality. Recently adaptive learning algorithms such as artificial neural networks have been implemented for the prediction of chlorophyll-a in reselwoirs. The advantage of artificial neural networks has been shown to be a cost-effective ***,their training has problems such as slow convergence and easy entrapment in a local *** this study,we present the application of a Particle swarm Optimization (PsO)model to predict changes of chlorophyll-a in agricultural reservoirs in Korean national *** were obtained from water quality monitoring networks of reservoirs opcrated by the Ministry of Agriculture and Forestry and the Ministry of Environment of Korea. Chlorophyll-a and environmental factors(DO,BOD,COD,ss,TN,TP, etc.)were measured at 440 reservoirs distributed in Korean national *** perceptron(MLP)was trained with PsO(MLP-PsO). Chlorophyll-a was well predicted by both standard MLP and MLP-PsO. We compared the performance of standard MLP and MLP-PsO for the prediction of chlorophyll-a with environment ***, MLP-PsO showed better result in training speed and prediction accuracy than standard MLP.

关键词： swarm PsO Prediction of chlorophyll-a in agricultural reservoirs of Korea using Particle swarm Optimization

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Microsystems & Nanoengineering 2024年第3期10卷 207-218页

作者： Useung Lee Hyein Kim Dong Kyo Oh Nayeong Lee Jonggab park Jaewon park Hyunji son Hyunchan Noh Junsuk Rho Jong G.Ok Department of Mechanical and Automotive Engineering Seoul National University of Science and TechnologySeoul 01811Republic of Korea Department of Mechanical Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Department of Chemical Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea POsCO-POsTECH-RIsT Convergence Research Center for Flat Optics and Metaphotonics Pohang 37673Republic of Korea National Institute of Nanomaterials Technology(NINT) Pohang 37673Republic of Korea Present address:Department of Mechanical Engineering Korea University145 Anam-roSeongbuk-guSeoul 02841Republic of Korea Research Team Hyundai Motor Group150 Hyundaiyeonguso-roHwaseong-siGyeonggi 18280Republic of Korea

We present an azimuthal-rotation-controlled dynamic nanoinscribing(ARC-DNI)process for continuous and scalable fabrication of asymmetric nanograting structures with tunable periods and shape profiles.A sliced edge of a nanograting mold,which typically has a rectangular grating profile,slides over a polymeric substrate to induce its burrfree plastic deformation into a linear *** this continuous nanoinscribing process,the“azimuthal angle,”that is,the angle between the moving direction of the polymeric substrate and the mold’s grating line orientation,can be controlled to tailor the period,geometrical shape,and profile of the inscribed *** modulating the azimuthal angle,along with other important ARC-DNI parameters such as temperature,force,and inscribing speed,we demonstrate that the mold-opening profile and temperature-and time-dependent viscoelastic polymer reflow can be controlled to fabricate asymmetric,blazed,and slanted nanogratings that have diverse geometrical profiles such as trapezoidal,triangular,and ***,period-and profile-tunable ARC-DNI can be utilized for the practical fabrication of diverse optical devices,as is exemplified by asymmetric diffractive optical elements in this study.

关键词： tunable asymmetric rotation

Leakage pressures for gasketless superhydrophobic fluid interconnects for modular lab-on-a-chip systems

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Microsystems & Nanoengineering 2021年第5期7卷 213-226页

作者： Christopher R.Brown Xiaoxiao Zhao Taehyun park Pin-Chuan Chen Byoung Hee You Daniel s.park steven A.soper Alison Baird Michael C.Murphy Center for Bio-Modular Multi-scale systems Louisiana State UniversityBaton RougeLA 70803USA Department of Mechanical&Industrial Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Mechanical and Industrial Engineering University of TorontoTorontoON M5S 3GBCanada school of Mechanical Engineering Kyungnam UniversityChangwonSouth Korea Department of Engineering Technology Texas State UniversitySan MarcosTX 78666USA Department of Mechanical Engineering The University of KansasLawrenceKS 66045USA Department of Chemistry The University of KansasLawrenceKS 66045USA sUNY Downstate stroke Center University Hospital of BrooklynBrooklynNY 11203USA

Chip-to-chip and world-to-chip fluidic interconnections are paramount to enable the passage of liquids between component chips and to/from microfluidic ***,most interconnect designs add additional physical constraints to chips with each additional interconnect leading to over-constrained microfluidic *** competing constraints provided by multiple interconnects induce strain in the chips,creating indeterminate dead volumes and misalignment between chips that comprise the microfluidic system.A novel,gasketless superhydrophobic fluidic interconnect(GsFI)that uses capillary forces to form a liquid bridge suspended between concentric through-holes and acting as a fluid passage was *** GsFI decouples the alignment between component chips from the interconnect function and the attachment of the meniscus of the liquid bridge to the edges of the holes produces negligible dead *** passive seal was created by patterning parallel superhydrophobic surfaces(water contact angle>150°)around concentric microfluidic ports separated by a *** relative position of the two polymer chips was determined by passive kinematic constraints,three spherical ball bearings seated in v-grooves.A leakage pressure model derived from the Young-Laplace equation was used to estimate the leakage pressure at failure for the liquid ***-molded,Cyclic Olefin Copolymer(COC)chip assemblies with assembly gaps from 3 to 240μm were used to experimentally validate the *** maximum leakage pressure measured for the GsFI was 21.4 kPa(3.1 psig),which corresponded to a measured mean assembly gap of 3μm,and decreased to 0.5 kPa(0.073 psig)at a mean assembly gap of 240μ*** effect of radial misalignment on the efficacy of the gasketless seals was tested and no significant effect was *** may be a function of how the liquid bridges are formed during the priming of the chip,but additional research is required to test that hypothesis.

关键词： passive interconnection fluid

全髋关节置换术中钴-铬股骨头不同磨损部位的摩擦学特性

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中华骨科杂志 2011年第9期31卷 1009-1014页

作者： C-T Duong s park J-s Nam E-M seo BP Patro J-D Chang s-s Lee school of Mechanical Engineering Pusan National U- niversity Busan Republic of Korea Orthopedic surgery and Institute for skeletal Aging Hallym University College of Medicine Cbuncheon Republic of Korea

通过使用原子力显微镜检查（atomic force microscopy，AFM）计算表面粗糙度和摩擦系数的方法，对工程和生物材料的摩擦学特性进行研究。尽管之前的大量研究对全髋关节置换术中不同承重材料的摩擦系数进行了报告，但却没有关于全髋关节... 详细信息

通过使用原子力显微镜检查（atomic force microscopy，AFM）计算表面粗糙度和摩擦系数的方法，对工程和生物材料的摩擦学特性进行研究。尽管之前的大量研究对全髋关节置换术中不同承重材料的摩擦系数进行了报告，但却没有关于全髋关节置换术术中轴承材料的表面粗糙度和摩擦系数的关系的报道。此外，钴-铬股骨头不同磨损部位的摩擦学特性尚不明确。因此，本研究对全髋关节置换术后10年钴-铬股骨头发生严重磨损及轻微磨损部位的表面粗糙度、摩擦系数和硬度之间的关系进行研究。钴-铬股骨头的平均维氏硬度为（380．7±11．3）HV。在AFM扫描的25μm×25μm面积内，严重磨损和轻微磨损部位的摩擦系数分别为0．229±0．054和0．243±0．059，两者差异无统计学意义（P=0．449）。严重磨损部位的表面粗糙度[Rq=（96．5±26．2）nm]与轻微磨损部位限[Rq=（17．7±4．2）nm]的差异有统计学意义（P〈0．0001）。本研究结果显示：钴-铬股骨头的摩擦特性与其表面粗糙度没有明显关系，为金属植入材料表面特性的改善提供了依据。

关键词：全髋关节置换术后摩擦学特性磨损部位股骨头表面粗糙度原子力显微镜检查铬钴

Influence of Reclamation Works on the Marine Environment in a semi-Enclosed Bay

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Journal of Ocean University of China 2006年第3期5卷 219-227页

作者： Lee M. Ock park s. Jin Kang T. soon Chonnam National University Republic of Korea Geosystem Research Corp. Republic of Korea

The flow and seawater exchange rates have been predicted using a two-dimensional numerical model and a Lagrangian method for a semi-enclosed shallow bay where reclaiming and dredging works are scheduled. The wind effect on the flow and material transport has been emphasized, and a thirty-year mean value of wind has been considered in the numerical simulation. As a whole, even after the reclaiming and dredging are conducted, the flow pattern looks similar to the original state. However, velocity variations up to 20% to 100% appear in the vicinity of the construction area. In the case of summcr wind forcing, the seawater exchange rate increases from 71.6% to 82.9% after the reclaiming and dredging, as indicated by a particle-tracking method. On the contrary, in the case of winter wind forcing, thc seawater cxchange rate appears to be 97.2% under natural conditions but decrcases slightly to 93.2% aftcr the rcclaiming and dredging. Thus, the wind forcing plays an important role in controlling the seawater exchangc rates. The seawater cxchange rate is further improved by 15% if the dredging is simultaneously carried out with the reclaiming. This suggests that the dredging can be an effective means to mitigate the variation of flow.

关键词： dredging random walk method reclaiming seawater exchange rate semi-enclosed bay wind forcing

Analysis of Conservative and Magnetically Induced Electric Fields in a Low-Frequency Birdcage Coil

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Journal of Electromagnetic Analysis and Applications 2013年第7期5卷 271-280页

作者： Bu s. park sunder s. Rajan Christopher M. Collins Leonardo M. Angelone Department of Radiology New York University New York USA Division of Physics Center for Devices and Radiological Health Office of Medical Products and Tobacco Food and Drug Administration Silver Spring USA

Numerical methods are used to evaluate variations of the electromagnetic fields generated by a head-sized birdcage coil as a function of load (“loading effect”). The loading effect was analyzed for the cases of a coil loaded with a conductive cylindrical sample, a dielectric cylindrical sample, and an anatomically precise head model. Maxwell equations were solved by means of finite difference time domain (FDTD) method conducted at 12.8, 64, and 128 MHz. simulation results indicate that at 12.8 MHz the conservative electric field (Ec) caused by the scalar electric potentials between the coil and the load or within the load was significantly higher than the magnetically-induced electric field (Ei) and was the major component of the total electric field (Etotal). The amplitudes of Ec and Etotal are seen to be lower within a sample than at a corresponding location in an empty coil, but approximately 65% higher in the space between coil and sample than at a corresponding location in an empty coil. This is due to polarization effects generating an additional scalar potential parallel to the original field. The increased electric field between coil and sample may cause increased power deposition at the surface of the sample and may affect the RF-induced currents in external leads used for physiological recording, i.e. ECG, during MRI scanning.

关键词： MRI FDTD Loading Effect Conservative Electric Field Birdcage Coil