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An Expert System to Detect Political Arabic Articles Orientation Using CatBoost Classifier Boosted by Multi-Level Features
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作者 Saad M.Darwish Abdul Rahman M.Sabri +1 位作者 Dhafar Hamed Abd Adel A.Elzoghabi 《Computer Systems Science & Engineering》 2024年第6期1595-1624,共30页
The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orient... The number of blogs and other forms of opinionated online content has increased dramatically in recent years.Many fields,including academia and national security,place an emphasis on automated political article orientation detection.Political articles(especially in the Arab world)are different from other articles due to their subjectivity,in which the author’s beliefs and political affiliation might have a significant influence on a political article.With categories representing the main political ideologies,this problem may be thought of as a subset of the text categorization(classification).In general,the performance of machine learning models for text classification is sensitive to hyperparameter settings.Furthermore,the feature vector used to represent a document must capture,to some extent,the complex semantics of natural language.To this end,this paper presents an intelligent system to detect political Arabic article orientation that adapts the categorical boosting(CatBoost)method combined with a multi-level feature concept.Extracting features at multiple levels can enhance the model’s ability to discriminate between different classes or patterns.Each level may capture different aspects of the input data,contributing to a more comprehensive representation.CatBoost,a robust and efficient gradient-boosting algorithm,is utilized to effectively learn and predict the complex relationships between these features and the political orientation labels associated with the articles.A dataset of political Arabic texts collected from diverse sources,including postings and articles,is used to assess the suggested technique.Conservative,reform,and revolutionary are the three subcategories of these opinions.The results of this study demonstrate that compared to other frequently used machine learning models for text classification,the CatBoost method using multi-level features performs better with an accuracy of 98.14%. 展开更多
关键词 Political articles orientation detection CatBoost classifier multi-level features context-based classification social networks machine learning stylometric features
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Orientation of Pigments in the Isolated PhotosystemⅡSub-core Reaction Center CP47/D1/D2/Cyt b-559 Complexes:A Linear Dichroism Study 被引量:3
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作者 侯建敏 Dominique DEJONGHE +2 位作者 单际修 李良璧 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第12期1211-1214,共4页
Linear dichroism (LD) spectroscopy is an important technique in the study of the orientation and organization of pigments in the photosynthetic membrane complexes in vivo and in vitro . In this work, the orient... Linear dichroism (LD) spectroscopy is an important technique in the study of the orientation and organization of pigments in the photosynthetic membrane complexes in vivo and in vitro . In this work, the orientation of the pigments in the isolated photosystem Ⅱ (PSⅡ) sub_core reaction center complexes was analyzed and characterized by means of low temperature absorption and LD spectroscopy. The preparations containing different amounts of CP47 isolated from spinach (Spinacia oleracea L.) chloroplast were used in order to investigate the orientation of pigments in the PSⅡ sub_core CP47/D1/D2/Cyt b_559 (CP47/D1/D2) complexes. Chlorophyll a (Chl a) absorbing at 680 nm in CP47/D1/D2/Cyt b_559 complex showed an orientation of the Q y transition parallel to the membrane plane. It is proposed that there are two forms of β_carotene (β_Car) in CP47/D1/D2/Cyt b_559 complex, denoted as β_Car (Ⅰ) and β_Car (Ⅱ), with different orientations, β_Car (Ⅰ) at 470 and 505 nm is roughly parallel to the membrane plane, and β_Car (Ⅱ) at 460 and 490 nm seems to be perpendicular orientation. Upon the photoinhibitory experiment β_Car (Ⅱ) was found to be photosensitive and easily photodamaged. It also showed that the positive LD signal observed at 680 nm was quite complicated. This signal is tentatively attributed to P680 and some Chl a of antenna in CP47 protein based upon our measurements. 展开更多
关键词 orientation of pigments photosystem linear dichroism spectroscopy PHOTOINHIBITION
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Transformation Method of Exterior Orientation Angular Elements Obtained via Position and Orientation System Under Gauss-Kruger Projection Coordinate System
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作者 YUAN Xiuxiao ZHANG Xueping FU Jianhong 《Geo-Spatial Information Science》 2010年第3期157-165,共9页
Data obtained via airborne position and orientation system (POS) is in WGS 84 global geocentric reference frame, while the national coordinate reference system for topographic mapping in China is generally Gauss-Kru... Data obtained via airborne position and orientation system (POS) is in WGS 84 global geocentric reference frame, while the national coordinate reference system for topographic mapping in China is generally Gauss-Kruger projection coordinate system. Therefore, data obtained via a POS must be transformed to national coordinate system. Owing to the effects of earth curvature and me- ridian deviation, there are some errors in the process of angle transformation from roll, pitch, and heading (φ,θ,ψ) obtained directly via a POS to the attitude angles of images (φ,ω,κ) needed in photogrammetry. On the basis of effect theories of earth curvature and meridian deviation on exterior orientation angular elements of images, a method using a compensation matrix to correct the transformation errors from attitude angles obtained via the POS to exterior orientation angular elements of images is proposed in this paper. Moreover, the rigorous formula of the compensation matrix is deduced. Two sets of actual data obtained via a POS AV 510, which are different in scale and terrain, are selected and used to perform experiments. The empirical results not only indicate that the compensation matrix proposed in this paper is correct and practical but also show that transformation accuracy of exterior orientation angular elements obtained via the POS based on compensation matrix is relevant to the selection of vertical axis (a projection of central meridian) of Gauss-Kruger projection coordinate system; the proper vertical axis should be the Gauss-Kruger projection of the central meridian of projection zone in which the survey area locates. However, the transformation accuracy of exterior orientation angular elements is irrelevant to the choice of origin of coordinate system; it is appropriate that the origin of coordinate system locates at the center point of the survey area. Moreover, transformation accuracy of exterior orientation angular elements achieved based on the compensa- tion matrix deduced in this paper is higher than that obtained via the existing POS processing software. 展开更多
关键词 position and orientation system (POS) exterior orientation elements of image earth curvature meridian deviation compensation matrix
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Orientation density and workspace analysis of a parallel stabilized platform testing system 被引量:1
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作者 江放 丁洪生 +1 位作者 付铁 董忠辉 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期302-308,共7页
An optimized workspace calculation method is proposed for parallel stabilized platform testing systems.This method refines the searched space progressively in order to approach the boundary of the workspace from both ... An optimized workspace calculation method is proposed for parallel stabilized platform testing systems.This method refines the searched space progressively in order to approach the boundary of the workspace from both the inside and the outside of it.The orientation density is defined and used as an evaluation index to calculate the orientation workspace.The algorithm of the orientation density is embedded into the computer program of the workspace calculation.Then the workspaces of the testing system are solved.In the solution,the orientation density is regarded as a discrete function of the reachable workspace.As a result,the reachable workspace and the orientation workspace are represented in the same multidimensional graphs.Finally the useful workspace of the testing system is determined based on these results.This case study indicates that the calculation efficiency is enhanced by adopting the optimized method and the practicability of workspace study is improved by proposing the orientation density. 展开更多
关键词 parallel mechanism stabilized platform workspace orientation density
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Avian orientation: multi-cue integration and calibration of compass systems
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作者 刘小峰 尼基塔.切尼佐夫 《Chinese Birds》 2012年第1期1-8,共8页
Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, includi... Migratory birds are known to use a number of different orientation cues to determine and maintain the direction of their movements. They are able to use at least three different sources of compass information, including solar, stellar and geomagnetic cues. However, little is known about how these cues are calibrated into uniform reference direction information, while the hierarchy of these cues remains controversial. In recent studies, researchers suggest that avian migrants calibrate their geomagnetic compass on sunset cues, whereas others fail to find such patterns and insist on the prevalence of the magnetic compass. We carefully reviewed the existing literature and suggest that the conflicting results reported by different authors are due to genuine variation among species and propose hypotheses to explain this variation. 展开更多
关键词 BIRDS orientation compass system geomagnetic field solar cues
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3D DEM simulation of hard rock fracture in deep tunnel excavation induced by changes in principal stress magnitude and orientation 被引量:2
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作者 Weiqi Wang Xia-Ting Feng +2 位作者 Qihu Wang Rui Kong Chengxiang Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3870-3884,共15页
To achieve the loading of the stress path of hard rock,the spherical discrete element model(DEM)and the new flexible membrane technology were utilized to realize the transient loading of three principal stresses with ... To achieve the loading of the stress path of hard rock,the spherical discrete element model(DEM)and the new flexible membrane technology were utilized to realize the transient loading of three principal stresses with arbitrary magnitudes and orientations.Furthermore,based on the deep tunnel of China Jinping Underground Laboratory II(CJPL-II),the deformation and fracture evolution characteristics of deep hard rock induced by excavation stress path were analyzed,and the mechanisms of transient loading-unloading and stress rotation-induced fractures were revealed from a mesoscopic perspective.The results indicated that the stressestrain curve exhibits different trends and degrees of sudden changes when subjected to transient changes in principal stress,accompanied by sudden changes in strain rate.Stress rotation induces spatially directional deformation,resulting in fractures of different degrees and orientations,and increasing the degree of deformation anisotropy.The correlation between the degree of induced fracture and the unloading magnitude of minimum principal stress,as well as its initial level is significant and positive.The process of mechanical response during transient unloading exhibits clear nonlinearity and directivity.After transient unloading,both the minimum principal stress and minimum principal strain rate decrease sharply and then tend to stabilize.This occurs from the edge to the interior and from the direction of the minimum principal stress to the direction of the maximum principal stress on theε1-ε3 plane.Transient unloading will induce a tensile stress wave.The ability to induce fractures due to changes in principal stress magnitude,orientation and rotation paths gradually increases.The analysis indicates a positive correlation between the abrupt change amplitude of strain rate and the maximum unloading magnitude,which is determined by the magnitude and rotation of principal stress.A high tensile strain rate is more likely to induce fractures under low minimum principal stress. 展开更多
关键词 Deep hard rock tunnel Three-dimensional(3D)discrete element model(DEM) Magnitude and orientation of principal stress Transient unloading Fracture mechanism
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Accelerated Sequential Deposition Reaction via Crystal Orientation Engineering for Low-Temperature,High-Efficiency Carbon-Electrode CsPbBr_(3) Solar Cells 被引量:1
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作者 Zeyang Zhang Weidong Zhu +10 位作者 Tianjiao Han Tianran Wang Wenming Chai Jiaduo Zhu He Xi Dazheng Chen Gang Lu Peng Dong Jincheng Zhang Chunfu Zhang Yue Hao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期168-175,共8页
Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation en... Low-temperature,ambient processing of high-quality CsPbBr_(3)films is demanded for scalable production of efficient,low-cost carbon-electrode perovskite solar cells(PSCs).Herein,we demonstrate a crystal orientation engineering strategy of PbBr_(2)precursor film to accelerate its reaction with CsBr precursor during two-step sequential deposition of CsPbBr_(3)films.Such a novel strategy is proceeded by adding CsBr species into PbBr_(2)precursor,which can tailor the preferred crystal orientation of PbBr_(2)film from[020]into[031],with CsBr additive staying in the film as CsPb_(2)Br_(5)phase.Theoretical calculations show that the reaction energy barrier of(031)planes of PbBr_(2)with CsBr is lower about 2.28 eV than that of(O2O)planes.Therefore,CsPbBr_(3)films with full coverage,high purity,high crystallinity,micro-sized grains can be obtained at a low temperature of 150℃.Carbon-electrode PSCs with these desired CsPbBr_(3)films yield the record-high efficiency of 10.27%coupled with excellent operation stability.Meanwhile,the 1 cm^(2)area one with the superior efficiency of 8.00%as well as the flexible one with the champion efficiency of 8.27%and excellent mechanical bending characteristics are also achieved. 展开更多
关键词 carbon-electrode perovskite solar cells crystal orientation engineering CsPbBr_(3) low temperature two-step sequential deposition
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Research for the orientation detection system using L-shape reticle
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作者 Liu Guangcan Bai Tingzhu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期49-53,共5页
The basic scheme of the orientation detection system using L-shape reticle is introduced. The dimension of the patterns on the reticle of the system in practical applications is designed and an analysis of the princip... The basic scheme of the orientation detection system using L-shape reticle is introduced. The dimension of the patterns on the reticle of the system in practical applications is designed and an analysis of the principle of abstracting the orientation information of the target and the effects and formation method of self-adapting tracking gate is presented. The research result shows that the orientation detection system using L-shape reticle has a good effect on space-filtering, the signals that the orientation detection system sends out are easy to be processed by computer, its self-adapting tracking gate has a strong anti-interference ability, and the whole system's searching and tracking performances are quite high. 展开更多
关键词 orientation detection system L-shape reticle Self-adapting tracking gate
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Effect of Tillage Systems and Vine Orientation on Yield of Sweet Potato (<i>Ipomoea batatas</i>L.)
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作者 I. Chagonda R. F. Mapfeka T. Chitata 《American Journal of Plant Sciences》 2014年第21期3159-3165,共7页
In Zimbabwe sweet potato (Ipomoea batatas L.) production is practiced under different tillage systems with varying vine orientations, which contribute to variable yields. Limited research on yield loss due to these di... In Zimbabwe sweet potato (Ipomoea batatas L.) production is practiced under different tillage systems with varying vine orientations, which contribute to variable yields. Limited research on yield loss due to these different practices is available despite that the majority of farmers are growing sweet potatoes to sustain their livelihoods. A field study was carried out at Midlands State University in the 2013/14 rainy season, to determine the effect of tillage systems and vine orientation on yield of sweet potato. A 2 × 3 factorial treatment structure in a randomized complete block design (RCBD), with three replications was used. Tillage systems had two factors (ridge and mound) and three vine orientations were used (horizontal, fold and loop). Data on storage root length, storage root diameter and storage root weight was subjected to Analysis of Variance (ANOVA) at 5% significance level. There was no interaction (p < 0.05) between tillage systems and vine orientations on storage root diameter, storage root length and storage root yield. The horizontal vine orientation gave statistically significant (p < 0.05) storage roots diameter of width 405 mm. Conversely the loop vine orientation had statistically the least (316 mm) storage root diameter. Horizontal vine orientation had significantly (p < 0.05) wider storage roots than the loop vine orientation. The ridge recorded longer (134.2 mm) mean storage root length, while those from mounds had shorter (115.9 mm) root length. The loop and the horizontal vine orientations recorded statistically the highest (35.5 t/ha and 34.8 t/ha respectively) sweet potato storage root yield. On the other hand, the fold vine orientation obtained significantly the lowest (28.7 t/ha) storage root yield. The research concluded that the horizontal and fold vine orientations had the widest storage root diameter and the ridge had longer storage root lengths. The loop and horizontal vine orientations are recommended in sweet potato production if high yields are to be achieved. 展开更多
关键词 TILLAGE system VINE orientation Sweet Potato Mound Ridge
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Orientation and Development of Telecom Resource Management System in China
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作者 Ye Yun Li Xiaojin (Network Division of ZTE Corporation,Nanjing 210012,China) 《ZTE Communications》 2003年第1期5-7,共3页
In consideration of the present conditions of telecom service providers in China,the objectives and possible processes of con- structing telecom resource management systems(RMS)in China are analyzed.The system boundar... In consideration of the present conditions of telecom service providers in China,the objectives and possible processes of con- structing telecom resource management systems(RMS)in China are analyzed.The system boundary with other network manage- ment systems and the interface protocols are discussed.It is sug- gested that the telecom resource management system should be constructed in a proper sequence and developed in different stages. 展开更多
关键词 of on or AS in orientation and Development of Telecom Resource Management system in China BOSS
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Towards Global Goal Orientation, Robustness and Integrity of Distributed Dynamic Systems
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作者 Peter Simon Sapaty 《International Relations and Diplomacy》 2016年第6期418-425,共8页
In an addition to the variety of topics in aims and scope of the Journal of International Relations and Diplomacy, we would be happy to offer here some more areas in line with its general orientation, which could be w... In an addition to the variety of topics in aims and scope of the Journal of International Relations and Diplomacy, we would be happy to offer here some more areas in line with its general orientation, which could be worth investigating, encouraging more paper submissions. These relate to effective organization of large distributed dynamic systems of diverse natures which may require innovative solutions reflecting the growing world dynamics in the 21 st century with emerging challenges and threats to local and global prosperity, stability, and safety. 展开更多
关键词 international relations world dynamics emerging challenges distributed systems goal orientation INTEGRITY INTEROPERABILITY over-operability
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Modeling of Orientation-Dependent Photoelastic Constants in Cubic Crystal System
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作者 Lubna Jahan Rashid Pinky Shakila Islam +2 位作者 Md. Nur Kutubul Alam Mohammad Arif Hossain Md. Rafiqul Islam 《Materials Sciences and Applications》 2014年第4期223-230,共8页
Euler’s rotation theorem and tensor rotation technique are applied to develop a generalized mathematical model for determining photoelastic constants in arbitrary orientation of cubic crystal system. Two times rotati... Euler’s rotation theorem and tensor rotation technique are applied to develop a generalized mathematical model for determining photoelastic constants in arbitrary orientation of cubic crystal system. Two times rotations are utilized in the model relating to crystallographic coordinates with Cartesian coordinates. The symmetry of photoelastic constants is found to have strong dependence with rotation angle. Using the model, one can determine photoelastic constants in any orientation by selecting appropriate rotation angle. The outcome of this study helps to characterize spatial variation of residual strain in crystalline as well as polycrystalline materials having cubic structure using the experimental technique known as scanning infrared polariscope. 展开更多
关键词 Mathematical Modeling Photoelastic CONSTANTS ARBITRARY Crystal orientation Euler’s ROTATION THEOREM TENSOR ROTATION Technique
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Research on the Reform Orientation of College Ideological and Political Course System under Background of Chinese Dream and New Normal
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作者 Jiaqian Zhang 《International Journal of Technology Management》 2016年第1期19-22,共4页
In this paper, we conduct research on the reform orientation of the college ideological and the political course system under background of the Chinese dream and new normal. The complex phenomenon of ideological and p... In this paper, we conduct research on the reform orientation of the college ideological and the political course system under background of the Chinese dream and new normal. The complex phenomenon of ideological and political education to our ideological and political education essence, grasp the law of ideological and political education to increase the difficulty. As an ideological and the political educators, it is necessary to continuously enhance the ability of dealing with the complex problems that is good at through the complex phenomenon of the ideological and political education, understanding and grasping the essence of the ideological and political education. We combine the primary analysis of the Chinese dream and new normal to form the optimal education paradigm for the college ideological and the political course system that is necessary. 展开更多
关键词 Reform orientation Ideological and Political Course system New Normal Dream.
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Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials
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作者 Xinyou He Shilin Su +3 位作者 Bao Zhang Zhiming Xiao Zibo Zhang Xing Ou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期213-222,I0005,共11页
Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in t... Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in the properties of Ni-rich cathodes.The disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is unclarified.Herein,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation process.Combining finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are unraveled.Specifically,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution behavior.Meanwhile,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic processes.Closed-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic performance.This precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes. 展开更多
关键词 Ni-rich cathode Grain orientation regulation Anisotropic microstructural change Precursor engineering Li~+-ions diffusion
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Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS
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作者 Jiaqi Hu Zheng Liu +1 位作者 Zuoliang Ning Hong Gao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期281-294,共14页
Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tes... Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS. 展开更多
关键词 Magnesium alloy orientation CORROSION Fatigue crack growth
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Entrepreneurial Orientation and Innovation Ecosystems in the Industrial Sector, Central Region, Kampala, Uganda: A Review
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作者 Serunjoji Ismah 《Open Journal of Applied Sciences》 2023年第12期2447-2460,共14页
This review explores entrepreneurial orientation and innovation ecosystems in the industrial sector of the Central Region, Kampala, Uganda, through an analysis of ten scholarly articles. The study contextualizes the r... This review explores entrepreneurial orientation and innovation ecosystems in the industrial sector of the Central Region, Kampala, Uganda, through an analysis of ten scholarly articles. The study contextualizes the research within the regional landscape and establishes a theoretical framework through a focused literature review. Key findings highlight the intersection of entrepreneurial activities and innovation dynamics, emphasizing the region’s unique contributions to the broader field. Discussions on discrepancies and unexplored territories within the articles offer insights into limitations and research gaps. The manuscript concludes by identifying future research avenues, providing a roadmap for ongoing inquiry into the entrepreneurial and innovative dimensions of the Central Region’s industrial sector. This synthesis underscores the importance of cultivating an entrepreneurial mindset and collaborative innovation strategies for sustainable industrial development in the region. 展开更多
关键词 Entrepreneurial orientation Innovation Ecosystems Industrial Sector Central Region Kampala Uganda Mixed Methods Collaborative Networks Proactiveness Risk-Taking Competitive Aggressiveness
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Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries
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作者 Hui Li Gang Wang +3 位作者 Jin Hu Jun Li Jiaxu Huang Shaolin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期129-139,共11页
The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines ... The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li dendrites.To address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current collectors.Specifically,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li deposition.Unlike approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance metrics.The half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge rate.This study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal batteries.The insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures. 展开更多
关键词 copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation
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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries
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作者 Haining Yin Zhaoxiang Wang +3 位作者 Lin Wang Jianhong Cao Jiakui Wang Zhumei Xi 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期713-731,共19页
Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with ... Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards. 展开更多
关键词 Vitis vinifera L. Orientated rows Berry composition SUGAR PHENOLIC Light quality Solar radiation
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Synergistic effect of orientation and temperature on slip behavior and precipitation behavior of Al−Cu−Li single crystals
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作者 Zhen JIANG Chen-qi LEI +4 位作者 Jia-jun DING Chun-nan ZHU Dong-feng SHI Jin ZHANG Guo-qing WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第11期3554-3568,共15页
The slip behavior and precipitation behavior of four Al−Cu−Li single crystals with varying orientations at different temperatures were investigated using electron backscattering diffraction(EBSD)and transmission elect... The slip behavior and precipitation behavior of four Al−Cu−Li single crystals with varying orientations at different temperatures were investigated using electron backscattering diffraction(EBSD)and transmission electron microscopy(TEM).The maximum differences in yield strength and ductility of the single crystals at room temperature are 41.6%and 14.7%,respectively.This indicates that the mechanical properties are strongly influenced by the crystal orientation.Moreover,grains with varying orientations exhibit distinct slip characteristics,including slip homogenization,slip localization,and multiple slip.In single crystal SC1,slip localization primarily contributes to its inferior ductility compared to other grains.Nevertheless,during deformation at 250℃,the distinct morphology and distribution of precipitates in the crystals are also correlated with orientation,which causes the increase in the maximum elongation difference to 20.8%in all selected single crystals.Notably,SC1,with a precipitate volume fraction of 2.65%,exhibits more severe slip localization compared to room temperature conditions,while SC2,with a precipitate volume fraction of 4.79%,demonstrates cross-slip characteristics,significantly enhancing the plastic deformation capacity of the Al−Cu−Li alloy. 展开更多
关键词 Al−Cu−Li alloy single crystal slip behavior oriented precipitation deformation mechanism
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Evaluation of New Graduate Nursing Orientation Program
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作者 Elizabeth Arroyo 《Open Journal of Nursing》 2024年第8期433-446,共14页
The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nu... The study site is a holistic patient-centered organization that has developed a 16-week long orientation program for new graduate nurses entering the hospital setting. The purpose of the program is for new graduate nurses to gain the confidence, competence, and critical thinking skills for providing safe patient care. The issue occurring within the organization is that there is an increasing rise in the number of turnover rates of new graduates leaving the hospital, thus making evaluating the program a necessity to problem-solving. There has been no evaluation of the program in the past five years to reveal why the increase in the recent turnover rates. The data collected during the interview process was coded and categorized into three main sections: organizational, substantive, and theoretical. The evaluator used an organizational category to investigate for board areas or issues within the problem attempting to be solved. The evaluator concluded from the results and findings that the issue, a poor preceptor-preceptee relationship was seen by all stakeholders involved. The literature presented concludes that continuous evaluation of orientation programs is crucial for the professional and personal growth of new graduate nurses in the hospital. 展开更多
关键词 New Graduate Nurses PRECEPTORS TURNOVER orientation
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