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Journal of Materials Science & Technology 2021年第20期79卷 15-20页

作者： Zhihua Dong Shuo Huang Valter ström Guocai Chai Lajos Károly Varga Olle Eriksson Levente Vitos Applied Materials Physics Department of Materials Science and EngineeringKTH-Royal Institute of TechnologyStockholm SE-10044Sweden College of Materials Science and Engineering Chongqing UniversityChongqing 400030China department of Physics and Astronomy Division of Materials TheoryUppsala UniversityUppsala SE-75121Sweden department of Materials Science and Engineering KTH-Royal Institute of TechnologyStockholm SE-10044Sweden Division of Engineering Materials Department of Management and EngineeringLinköping UniversityLinköping SE-58183Sweden AB Sandvik Materials Technology R&D Center Sandviken SE-81181Sweden School of Science and Technology Örebro UniversityÖrebro SE-70281Sweden Research Institute for Solid State Physics and Optics Wigner Research Center for PhysicsP.O.Box 49H-1525 BudapestHungary

High entropy alloys(HEAs)based on transition metals display rich magnetic characteristics,however attempts on their application in energy efficient technologies remain ***,we explore the magnetocaloric application for a series of Mn_(x)Cr_(0.3)Fe_(0.5)Co_(0.2)Ni_(0.5)Al_(0.3)(0.8designed HEAs have the Curie temperature close to room temperature and is tunable with Mn concentration.A non-monotonic evolution is observed for both the entropy change and the relative cooling power with changing Mn *** underlying atomic mechanism is found to primarily emerge from the complex impact of Mn on *** magnetocaloric properties can be achieved by tuning Mn concentration in combination with controlling structural phase stability for the designed HEAs.

关键词： High entropy alloys Magnetocaloric materials Magnetic phase transition Experiment and Ab initio

基于计算机视觉的藏式古建筑石砌体壁画墙裂缝生长变形监测

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Polydopamine-based redox-active separators for lithium-ion batteries

工程力学 2025年第1期42卷 129-142页

作者：杨娜王烁汪德佳北京交通大学土木建筑工程学院北京100044

对单一背景下裂缝的定期检测研究已取得一定成果，但对复杂背景下裂缝预防性长期生长变形监测的研究尚处于起步阶段。该文综合古建筑壁画墙变形微量和不宜扰动的特点，基于计算机视觉研究了传统图像分割处理技术和裂缝图像智能语义分割... 详细信息

对单一背景下裂缝的定期检测研究已取得一定成果，但对复杂背景下裂缝预防性长期生长变形监测的研究尚处于起步阶段。该文综合古建筑壁画墙变形微量和不宜扰动的特点，基于计算机视觉研究了传统图像分割处理技术和裂缝图像智能语义分割神经网络模型，建立了一套非接触式、预防性生长变形监测系统。为降低壁画墙裂缝特有的彩绘壁画、环境光照及噪声等干扰，有效地将裂缝从复杂背景中分离出来，在传统阈值分割算法系统中，通过SIFT特征匹配和单应性矩阵的求解，解决图像视角差异问题，通过对比不同滤波算法，选择更适用于壁画墙裂缝分割的双边滤波算法与阈值分割相结合的监测算法;在智能语义分割系统中，采用多层卷积、采样和拼接等操作，去除多余特征，重构裂缝高级语义特征图，选择多步优化策略改进原U-Net模型网络架构，提升模型测试平均准确率至0.9899。监测12天典型藏式古建筑石砌体壁画墙裂缝，提取裂缝轮廓及裂缝骨架线等相关特征参数作为关键指标定量描述裂缝生长变化信息，发现：传统阈值分割算法二维特征指标(如裂缝面积、密度、宽度)的变异系数COV值处于4.50%~6.52%，改进的U-Net模型将传统方案中数据波动最大的裂缝面积COV由6.52%降至3.53%，提高了监测系统对壁画色彩、光照和阴影干扰的鲁棒性;系统中两类算法分别处理了不同视角下的同一裂缝的12张图像，输出的数据具备均匀一致性，COV不超过7%，证明了该监测系统为壁画墙裂缝的生长变形提供实时无损监测的技术可行性。

关键词：藏式古建筑壁画墙裂缝阈值分割算法神经网络模型特征参数

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Journal of Materiomics 2019年第2期5卷 204-213页

作者： Ruijun Pan Zhaohui Wang Rui Sun Jonas Lindh Kristina Edstrom Maria strømme Leif Nyholm department of Chemistry-Ångstr€om Laboratory Uppsala UniversityBox 538SE-75121UppsalaSweden Nanotechnology and Functional Materials Department of Engineering SciencesTheÅngstr€om LaboratoryUppsala UniversityBox 534SE-75121UppsalaSweden

The performance of lithium-ion batteries(LIBs)can be effectively enhanced with functionalized ***,it is demonstrated that polydopamine-based redox-active(PRA)separators can provide additional capacity to that of typical anode materials,increase the volumetric capacity of the cell,as well as,decrease the cell resistance to yield an improved performance at higher cycling *** PRA separators,which are composed of a 2 mm thick electrically insulating nanocellulose fiber(NCF)layer and an 18 mm thick polydopamine(PDA)and carbon nanotube(CNT)containing redox-active layer,are readily produced using a facile paper-making *** PRA separators are also easily wettable by commonly employed electrolytes(***40)and exhibit a high dimensional *** addition,the pore structure endows the PRA separator with a high ionic conductivity(i.e.1.06 mS cm^(-1))that increases the rate performance of the *** to the presence of the redox-active layer,Li_(4)Ti_(5)O_(12)(LTO)half-cells containing PRA separator were found to exhibit significantly higher capacities than the corresponding cells containing commercial *** results clearly show that the implementation of this type of redox-active separators constitutes a straightforward and effective way to increase the energy and power densities of LIBs.

关键词： Lithium-ion battery Separator Cellulose Polydopamine Redox-active

Label-free superior contrast with c-band ultra-violet extinction microscopy

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Light(Science & Applications) 2023年第3期12卷 435-445页

作者： Florian ströhl deanna L.Wolfson Ida S.Opstad Daniel H.Hansen Hong Mao Balpreet S.Ahluwalia department of Physics and Technology UiT The Arctic University of NorwayTromsøNorway department of Clinical Science Intervention and TechnologyKarolinska InstituteStockholmSweden

In 1934,Frits Zernike demonstrated that it is possible to exploit the sample’s refractive index to obtain superior contrast images of biological *** refractive index contrast of a cell surrounded by media yields a change in the phase and intensity of the transmitted light *** change can be due to either scattering or absorption caused by the *** cells are transparent at visible wavelengths,which means the imaginary component of their complex refractive index,also known as extinction coefficient k,is close to ***,we explore the use of c-band ultra-violet(UVC)light for high-contrast high-resolution label-free microscopy,as k is naturally substantially higher in the UVC than at visible *** differential phase contrast illumination and associated processing,we achieve a 7-to 300-fold improvement in contrast compared to visible-wavelength and UVA differential interference contrast microscopy or holotomography,and quantify the extinction coefficient distribution within liver sinusoidal endothelial *** a resolution down to 215 nm,we are,for the first time in a far-field label-free method,able to image individual fenestrations within their sieve plates which normally requires electron or fluorescence superresolution *** illumination also matches the excitation peak of intrinsically fluorescent proteins and amino acids and thus allows us to utilize autofluorescence as an independent imaging modality on the same setup.

关键词： wave. extinction violet

Cross-Polarized GPR Imaging of Fracture Flow Channeling

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Journal of Earth Science 2015年第6期26卷 776-784页

作者： Georgios P.Tsoflias Christopher Perll matthew Baker matthew W.Becker department of Geology the University of Kansas Chesapeake Energy Marathon Oil Corporation California State University Long Beach

Ground penetrating radar（GPR） can be used to image fractures and monitor fluid flow in the subsurface. Conventional GPR imaging uses single-polarization, co-polarized acquisition. We examine the use of cross-polarized GPR signals for imaging flow channeling in a discrete horizontal fracture. Numerical modeling（FDTD） demonstrates that when the fracture channel is oriented at an oblique angle to the survey line, depolarization of the GPR signal results in scattered energy along the cross-polarized components. When the channel is oriented parallel or orthogonal to the survey line, all scattered energy is captured by the co-polarized components and no signal is present in the cross-polarized orientation. Multipolarization, time-lapse 3D GPR field data were acquired at the Altona Flat Rock test site in New York State. The GPR surveys were conducted during background fresh fracture water conditions and during a natural gradient saline tracer test which was used to highlight flow channels along a sub-horizontal fracture. Amplitude analysis of the cross-polarized data reveals flow channeling that is in agreement with the co-polarized GPR images and with independent hydraulic tests. This investigation demonstrates that cross-polarized components of GPR signals can be used to enhance imaging of flow channels in fractured media.

关键词： GPR single-polarization cross-polarized data rapid flow saline tracer fractured rock.

Technical note: Anterior cruciate ligament reconstruction in the presence of an intramedullary femoral nail using anteromedial drilling

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World Journal of Orthopedics 2017年第5期8卷 379-384页

作者： matthew Lacey Joseph Lamplot Kempland C Walley Joseph P de Angelis Arun J Ramappa department of Orthopaedic Surgery Harvard Medical School Beth Israel Deaconess Medical Center

AIM To describe an approach to anterior cruciate ligament(ACL) reconstruction using autologous hamstring by drilling via the anteromedial portal in the presence of an intramedullary(IM) femoral *** Once preoperative imagining has characterized the proposed location of the femoral tunnel preparations are made to remove all of the hardware(locking bolts and IM nail). A diagnostic arthroscopy is performed in the usual fashion addressing all intra-articular pathology. The ACL remnant and lateral wall soft tissues are removed from the intercondylar, to provide adequate visualization of the ACL footprint. Femoral tunnel placement is performed using a transportal ACL guide with desired offset and the knee flexed to 2.09 rad. The Beath pin is placed through the guide starting at the ACL's anatomic footprint using arthroscopic visualization and/or fluoroscopic guidance. If resistance is met while placing the Beath pin, the arthroscopy should be discontinued and the obstructing hardware should be removed under fluoroscopic guidance. When the Beath pin is successfully placed through the lateral femur, it is overdrilled with a 4.5 mm Endobutton drill. If the Endobutton drill is obstructed, the obstructing hardware should be removed under fluoroscopic guidance. In this case, the obstruction is more likely during Endobutton drilling due to its larger diameter and increased rigidity compared to the Beath pin. The femoral tunnel is then drilled using a best approximation of the graft's outer diameter. We recommend at least 7 mm diameter to minimize the risk of graft failure. Autologous hamstring grafts are generally between 6.8 and 8.6 mm in diameter. After reaming, the knee is flexed to 1.57 rad, the arthroscope placed through the anteromedial portal to confirm the femoral tunnel position, referencing the posterior wall and lateral cortex. For a quadrupled hamstring graft, the gracilis and semitendinosus tendons are then harvested in the standard fashion. The tendons are

关键词： Anteromedial drilling Intramedullary femoral nail Anterior cruciate ligament reconstruction Retained hardware

The effect of powder size on the mechanical and corrosion properties and the ignition temperature of WE43 alloy prepared by spark plasma sintering

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Journal of Magnesium and Alloys 2021年第4期9卷 1356-1369页

作者： Drahomír Dvorský JiríKubásek Michaela Roudnická Filip Pruša David Necas Peter Minárik Jitka stráská Dalibor Vojtech University of Chemistry and Technology Faculty of Chemical TechnologyDepartment of Metals and Corrosion EngineeringTechnická516628 Praha 6–DejvicePragueCzech Republic Institute of Physics Czech Academy of ScienceNa Slovance 1999/218221 Praha 8PragueCzech Republic department of Physics of Materials Charles UniversityKe Karlovu 5Prague 12116Czech Republic

Powder metallurgy is a powerful method for the preparation of materials with superior *** work aimed to investigate the effect of powder size on the microstructure,mechanical,and corrosion properties of advanced WE43(Mg-4Y-3REE-Zr)alloy prepared by spark plasma sintering(SPS).At the same time,the effect of HF pre-treatment of the powder on the properties of final compacted products is *** powder particles yielded microstructure with more interfaces formed by Y_(2)O_(3),or MgF_(2) and YF_(3).These interfaces work as barriers against corrosion,which greatly improves corrosion *** suggested pre-treatment of powder in HF further reduced the corrosion rate of the compacted *** the contrary,fragile interfaces of YF_(3) decreased mechanical properties as the crack primarily propagates through these *** original powder containing the mixture of all powder fractions exerted the best combination of mechanical *** size has also shown to affect ignition *** highest ignition temperature was measured for the finest powder fraction.

关键词： Powder metallurgy Mechanical properties Corrosion Interface SPS

Evaluation of a software positioning tool to support SMEs in adoption of big data analytics

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Journal of Electronic Science and Technology 2024年第1期22卷 13-24页

作者： matthew Willetts Anthony S.Atkins Faculty of Digital TechnologyInnovationand BusinessStaffordshire UniversityStoke-on-TrentST42DEUnited Kingdom

Big data analytics has been widely adopted by large companies to achieve measurable benefits including increased profitability,customer demand forecasting,cheaper development of products,and improved stock *** and medium sized enterprises(SMEs)are the backbone of the global economy,comprising of 90%of businesses ***,only 10%SMEs have adopted big data analytics despite the competitive advantage they could *** research has analysed the barriers to adoption and a strategic framework has been developed to help SMEs adopt big data *** framework was converted into a scoring tool which has been applied to multiple case studies of SMEs in the *** paper documents the process of evaluating the framework based on the structured feedback from a focus group composed of experienced *** results of the evaluation are presented with a discussion on the results,and the paper concludes with recommendations to improve the scoring tool based on the proposed *** research demonstrates that this positioning tool is beneficial for SMEs to achieve competitive advantages by increasing the application of business intelligence and big data analytics.

关键词： Big data analytics Evaluation Small and medium sized enterprises (SMEs) strategic framework

Extrapulmonary sarcoidosis of liver and pancreas: A case report and review of literature

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World Journal of Gastroenterology 2007年第17期13卷 2504-2509页

作者： Hermann Harder Markus W Büchler Boris Frhlich Philipp strbel Frank Bergmann Wolfgang Neff Manfred V Singer department of Medicine Ⅱ (Gastroenterology Hepatology and Infectious Diseases) University Hospital of Heidelberg at Mannheim Germany department of Surgery University of Heidelberg GermanyFrank Bergmann Institute of Pathology University of Heidelberg Germany Institute of Pathology University Hospital of Heidelberg at Mannheim Germany Institute of Pathology University of HeidelbergGermany Institute of Radiology University Hospital of Heidelberg at Mannheim Germany

Sarcoidosis is a chronic multisystemic granulomatous disease of unknown origin, which can involve nearly all organs. In the case of an infrequent gastrointestinal tract involvement in systemic sarcoidosis, granulomas of the liver are most commonly described while isolated pancreatic sarcoid lesions are rarely seen. We report a case of systemic sarcoidosis with exclusive extrapulmonal involvement of the liver and the pancreas in a 71-year- old white man. The diagnosis of liver involvement was confirmed by biopsy. Pancreatic surgery was needed because preoperative evaluation could not exclude pancreatic cancer and for biliary decompression. An extensive literature review of systemic sarcoidosis, focusing on reported cases with unusual presentation of sarcoidosis in the liver and the pancreas, its diagnosis, treatment, and prognosis was made.

关键词： Systemic Sarcoidosis Extrapulmonary Liver Pancreas

detection of a Quasiperiodic Phenomenon of a Binary Star System Using Convolutional Neural Network

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Intelligent Automation & Soft Computing 2023年第9期37卷 2519-2535页

作者： denis Benka Sabína Vasová Michal Kebísek Maximilián strémy Institute of Applied Informatics Automation and MechatronicsFaculty of Materials Science and TechnologySlovak University of TechnologyTrnava91724Slovakia

Pattern recognition algorithms are commonly utilized to discover certain patterns,particularly in image-based *** study focuses on quasiperiodic oscillations(QPO)in celestial objects referred to as cataclysmic variables(CV).We are dealing with interestingly indistinct QPO signals,which we analyze using a power density spectrum(PDS).The confidence in detecting the latter using certain statistical approaches may come out with less significance than the *** work with real and simulated QPO data of a CV called MV *** primary statistical tool for determining confidence levels is sigma *** aforementioned CV has scientifically proven QPO existence,but as indicated by our analysis,the QPO ended up falling below 1-σ,and such QPOs are not noteworthy based on the former *** intend to propose and ultimately train a convolutional neural network(CNN)using two types of QPO data with varying amounts of training dataset *** aim to demonstrate the accuracy and viability of the classification using a CNN in comparison to sigma *** resulting detection rate of our algorithm is very plausible,thus proving the effectiveness of CNNs in this scientific area.

关键词： Convolutional neural network quasi-periodic oscillation cataclysmic variable simulation