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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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作者 Yasmin Alaa Hassan Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2024年第1期1423-1442,共20页
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))... Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness. 展开更多
关键词 Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding
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Estimation of Displacement and Extension due to Reverse Drag of Normal Faults: Forward Method
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作者 Shunshan Xu Angel Francisco Nieto-Samaniego +1 位作者 Huilong Xu Susana Alicia Alaniz-Álvarez 《International Journal of Geosciences》 CAS 2024年第1期25-39,共15页
In the case of reverse drag of normal faulting, the displacement and horizontal extension are determined based on the established equations for the three mechanisms: rigid body, vertical shear and inclined shear. Ther... In the case of reverse drag of normal faulting, the displacement and horizontal extension are determined based on the established equations for the three mechanisms: rigid body, vertical shear and inclined shear. There are three sub-cases of basal detachment for the rigid body model: horizontal detachment, antithetic detachment and synthetic detachment. For the rigid body model, the established equations indicate that the total displacement on the synthetic base (D<sub>t2</sub>) is the largest, that on the horizontal base (D<sub>t1</sub>) is moderate, and that on the antithetic base (D<sub>t3</sub>) is the smallest. On the other hand, the value of (D<sub>t1</sub>) is larger than the displacement for the vertical shear (D<sub>t4</sub>). The value of (D<sub>t1</sub>) is larger than or less than the displacement for the inclined shear (D<sub>t5</sub>) depending on the original fault dip δ<sub>0</sub>, bedding angle θ, and the angle of shear direction β. For all original parameters, the value of D<sub>t5</sub> is less than the value of D<sub>t4</sub>. Also, by comparing three rotation mechanisms, we find that the inclined shear produces largest extension, the rigid body model with horizontal detachment produces the smallest extension, and the vertical shear model produces moderate extension. 展开更多
关键词 Fault Rotation Fault Drag Fault Displacement extension Forward Model
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Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al
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作者 Biaobiao Yang Javier LLorca 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1186-1203,共18页
A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction... A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction.The deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice rotation.It was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple junctions.They were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice rotations.Moreover,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain incompatibility.These results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations. 展开更多
关键词 Magnesium extension twinning In-situ electron back-scattered diffraction basal slip Deformation mechanisms.
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Comparative Study of the Socioeconomic Characteristics and Digital Literacy Level of Agricultural Extension Personnel in Imo and Ebonyi States, South-East, Nigeria
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作者 Ogbonnaya Okoro Aja Cyril Chigozie Asiabaka +1 位作者 Anthony Okorie Ani Edna Chioma Matthews-Njoku 《Agricultural Sciences》 2024年第2期230-245,共16页
The study comparatively analysed the socioeconomic characteristics and digital literacy level of Agricultural Extension personnel (AEP) in Ebonyi and Imo States, South-East, Nigeria. The specific objectives were to de... The study comparatively analysed the socioeconomic characteristics and digital literacy level of Agricultural Extension personnel (AEP) in Ebonyi and Imo States, South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in Ebonyi and Imo States, and to ascertain the digital literacy level of AEP in the studied states. Purposive sampling technique was used to select 312 Agricultural Extension personnel (132 from Ebonyi State Agricultural Development Program and 180 from Imo State Agricultural Development Program) for the study. Data were collected through the use of validated and structured questionnaire, and administered through the help of well-trained enumerators. Data were analysed using simple descriptive statistical tools such as percentages mean score, standard deviation and weighted mean. Findings indicated that they were more male in the both States (55.3% and 57.8%) for Ebonyi and Imo State respectively and that the average age of AEP in Ebonyi and Imo States were 44.7 years and 49.2 years respectively. It was further revealed that the majority (77.3% and 82.8%) had B.Sc./HND as their highest academic qualifications, belonged to professional organisations (62.1% and 75%), and were earning an average monthly income of N58,798 and N62,648 for Ebonyi and Imo State respectively. Also, it was revealed that their mean years of service were 12.4 years and 13.4 years for Ebonyi and Imo State respectively. Almost all of them (87.9% and 95.0%) own a smartphone, had access to the internet (80.3% and 90.0%), but do not own a laptop/ipad (82.6% and 72.8%) for Ebon-yi and Imo State respectively. Results further revealed that Agricultural extension personnel in both Ebonyi and Imo State respectively had low digital literacy level ( = 2.41 and 2.32). The study concluded that AEP in Ebonyi and Imo State respectively had similar socioeconomic characteristics and low level of digital literacy. The study recommended that the management of ADPs in both Ebonyi and Imo State should ensure the training of AEP in digital skills to enhance their digital literacy level to enable them use digital technologies in their work. 展开更多
关键词 Agricultural extension Personnel Digital Literacy Ebonyi State Imo State Socioeconomic Characteristics
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Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region
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作者 ZHANG Shuqin LIAO Qinghua +4 位作者 LIU Chunlei GAO Xiaoyu LONG Jingchao LI Pengyuan XU Jianjun 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期605-617,共13页
Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-Apr... Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification. 展开更多
关键词 explosive cyclone diabatic heating cyclonic-vorticity advection rapid intensification the Kuroshio/Kuroshio extension region
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Wellbore Cleaning Degree and Hydraulic Extension in Shale Oil Horizontal Wells
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作者 Xin Ai Mian Chen 《Fluid Dynamics & Materials Processing》 EI 2024年第3期661-670,共10页
The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investiga... The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentallyby focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontalwellhydraulic extension taking into account the influence of the wellbore cleaning degree on the wellborepressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulatingpressure drop, the drilling pump performance and the formation properties. The analysis shows that the hydraulicextension of horizontal wells decreases with an increase in the cuttings bed height, and the higher the displacementof drilling fluid, the faster the hydraulic extension declines. The annular pressure drop of the horizontalsection increases with the increase of the cuttings bed height, resulting in a higher bottom-hole pressure. Severalarguments are provided to guide the safe drilling of shale oil horizontal wells and overcome the limits of currenttechnological approaches. 展开更多
关键词 Shale oil horizontal well hydraulic extension wellbore cleaning degree pressure distribution mechanism analysis
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H-separable Hopf Galois Extensions and Azumaya Algebra
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作者 祝家贵 《Northeastern Mathematical Journal》 CSCD 2001年第3期269-273,共5页
Let H be a finite dimensional semisimple Hopf algebra over a field and A an H-module algebra. In this paper, we characterize any H-separable Galois extension of an Azumaya algebra. Assuming that A/AH is an H-separable... Let H be a finite dimensional semisimple Hopf algebra over a field and A an H-module algebra. In this paper, we characterize any H-separable Galois extension of an Azumaya algebra. Assuming that A/AH is an H-separable extension, we prove that A/AH is H-Galois and AH is Azumaya if and only if A#H is an Azumaya Z-algebra, where Z is the center of A#H(not necessarily C(A)H). 展开更多
关键词 Azumaya algebra separable extension smash product
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Mechanical behavior of iron ore tailings under standard compression and extension triaxial stress paths 被引量:1
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作者 Alexia Cindy Wagner João Paulo de Sousa Silva +5 位作者 João Vítor de Azambuja Carvalho Ana Luisa Cezar Rissoli Pedro Pazzoto Cacciari Helder Mansur Chaves Hugo Carlos Scheuermann Filho Nilo Cesar Consoli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第7期1883-1894,共12页
The disposal of mining tailings has increasingly focused on the use of dry stacks.These structures offer more security since they use filtered and compacted material.Because of the construction method and the heights ... The disposal of mining tailings has increasingly focused on the use of dry stacks.These structures offer more security since they use filtered and compacted material.Because of the construction method and the heights achieved,the material that compounds the structure can be subjected to different stress paths along the failure plane.The theoretical framework considered in the design of these structures generally is the critical state soil mechanics(CSSM).However,the data in the literature concerning the uniqueness of critical state line(CSL)is still controversial as the soil is subjected to different stress paths.With respect to tailings,this question is even more restricted.This paper studies two tailings with different gradings due to the beneficial processes over extension and compression paths.A series of drained and undrained triaxial tests was conducted over a range of initial densities and stress levels.In the q-p'plane,different critical stress ratio(M)values were obtained for compression and extension stress paths.However,the critical state friction angle is very similar with a slightly higher critical state friction angle for extension tests.Curved stress path dependent CSLs were obtained in the n-lnp0 plane with the extension tests below the CSL defined in compression.Regarding the fines content,the studied tailings presented very similar M and critical state friction angle values.However,the fines content af-fects the volumetric behavior of the studied tailings and the CSLs on the n-lnp0 plane shift downwards with the increasing fines content for compression and extension tests.In relation to dilatancy analysis,the fines content did not present an evident influence on the dilatancy of the materials.However,different values of mean stress ratio N were obtained between compression and extension tests and can corroborate the existence of non-unique CSLs for these materials. 展开更多
关键词 Iron ore tailings(IOTs) Dry stacking Critical state soil mechanics extension tests Stress path
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代数几何码的Galois对偶码的Weil微分表示
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作者 李家齐 马立明 《中国科学技术大学学报》 CAS CSCD 北大核心 2023年第12期53-58,I0008,I0010,共8页
Galois对偶码是Euclid对偶码和Hermite对偶码的推广。我们证明了函数域F=F_(p)^(e)上代数几何码C_(L,F)(D,G)的h-Galois对偶码是F′=F_(p)^(e)上的代数几何码C_(Ω,F′)(ϕ_(h)(D),ϕ_(h)(G)),其中,F′=F_(p)^(e)是一个与F=F_(p)^(e)有关... Galois对偶码是Euclid对偶码和Hermite对偶码的推广。我们证明了函数域F=F_(p)^(e)上代数几何码C_(L,F)(D,G)的h-Galois对偶码是F′=F_(p)^(e)上的代数几何码C_(Ω,F′)(ϕ_(h)(D),ϕ_(h)(G)),其中,F′=F_(p)^(e)是一个与F=F_(p)^(e)有关的函数域,ϕ_(h)是从F到F′的同构映射,并且对任意a∈F_(p)^(e)满足ϕ_(h)(a)=a^(p)^(e-h).作为上述结果的应用,我们构造了一类h-Galois LCD MDS码。 展开更多
关键词 代数几何码 galois对偶码 galois线性补对偶码 MDS码
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由二阶循环矩阵构造Hopf-Galois代数与拟三角Hopf代数
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作者 李安 方云霏 +2 位作者 常志诚 黄芯琪 张良云 《南京师大学报(自然科学版)》 CAS 北大核心 2023年第3期6-11,共6页
本文分别由二阶循环矩阵构造了Hopf-Galois代数与Hopf代数,最后,由二阶循环矩阵构造拟三角Hopf代数.
关键词 循环矩阵 Hopf-galois代数 HOPF代数 拟三角HOPF代数
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Clinical value of ankle flexion and extension exercises combined with a psychological intervention in knee osteoarthritis 被引量:1
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作者 Yang Liu Rong Chen +4 位作者 Yang Zhang Qin Wang Jiang-Li Ren Chang-Xu Wang Yuan-Kun Xu 《World Journal of Psychiatry》 SCIE 2023年第10期743-752,共10页
BACKGROUND Considering the limited effectiveness of clinical interventions for knee osteoarthritis(KOA),it is necessary to continue to explore appropriate and effective treatment strategies to improve the condition of... BACKGROUND Considering the limited effectiveness of clinical interventions for knee osteoarthritis(KOA),it is necessary to continue to explore appropriate and effective treatment strategies to improve the condition of KOA patients.AIM To clarify the influence of ankle flexion and extension exercises combined with a psychological intervention on the psychological status and activities of daily living(ADLs)of patients with KOA.METHODS The research participants were 116 KOA patients admitted to The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine between May 2019 and May 2022,including 54 patients receiving routine treatment,care and psychological intervention(control group)and 62 patients additionally treated with ankle flexion and extension exercises(research group).The two groups were comparatively analyzed in terms of psychological status(Self-rating Anxiety/Depression Scale,SDS/SAS),ADLs,knee joint function(Lysholm Knee Scoring Scale),pain(Visual Analog Scale,VAS),fatigue(Multidimensional Fatigue Inventory,MFI),and quality of life(QoL;Short-Form 36 Item Health Survey,SF-36).RESULTS After evaluation,it was found that the postinterventional SDS,SAS,VAS,and MFI scores in the research group were significantly reduced compared with the baseline(before the intervention)values and those of the control group,while the postinterventional Lysholm,ADL and SF-36 scores were markedly elevated.CONCLUSION Therefore,ankle flexion and extension exercises are highly effective in easing negative psychological status,enhancing ADLs,daily living ability,knee joint function and QoL,and relieving pain and fatigue in KOA patients,thus warranting clinical promotion. 展开更多
关键词 Ankle flexion and extension exercises Knee osteoarthritis PSYCHOLOGY Negative emotions Activities of daily living Quality of life
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Asymmetric Key Cryptosystem for Image Encryption by Elliptic Curve over Galois Field GF(2^(n))
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作者 Mohammad Mazyad Hazzazi Hafeez Ur Rehman +1 位作者 Tariq Shah Hajra Younas 《Computers, Materials & Continua》 SCIE EI 2023年第8期2033-2060,共28页
Protecting the integrity and secrecy of digital data transmitted through the internet is a growing problem.In this paper,we introduce an asymmetric key algorithm for specifically processing images with larger bit valu... Protecting the integrity and secrecy of digital data transmitted through the internet is a growing problem.In this paper,we introduce an asymmetric key algorithm for specifically processing images with larger bit values.To overcome the separate flaws of elliptic curve cryptography(ECC)and the Hill cipher(HC),we present an approach to picture encryption by combining these two encryption approaches.In addition,to strengthen our scheme,the group laws are defined over the rational points of a given elliptic curve(EC)over a Galois field(GF).The exclusive-or(XOR)function is used instead of matrix multiplication to encrypt and decrypt the data which also refutes the need for the inverse of the key matrix.By integrating the inverse function on the pixels of the image,we have improved system security and have a wider key space.Furthermore,through comprehensive analysis of the proposed scheme with different available analyses and standard attacks,it is confirmed that our proposed scheme provides improved speed,security,and efficiency. 展开更多
关键词 Elliptic curve galois field group law hill cipher
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Dislocation configuration evolution during extension twinning and its influence on precipitation behavior in AZ80 wrought magnesium alloy
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作者 Guo-Liang Shi Kui Zhang +4 位作者 Xing-Gang Li Yong-Jun Li Ming-Long Ma Jia-Wei Yuan Hong-Ju Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第7期2442-2457,共16页
Thermomechanical treatment T10(extension twinning+aging treatment)can largely enhance the precipitation strengthening effect of magnesium alloys.In this study,dislocation structure evolution and precipitation behavior... Thermomechanical treatment T10(extension twinning+aging treatment)can largely enhance the precipitation strengthening effect of magnesium alloys.In this study,dislocation structure evolution and precipitation behavior during T10 treatment of an AZ80 extruded bar were analyzed mainly by two-beam diffraction in TEM.At a compressive strain of 1%in the extrusion direction(ED),a typical dislocation configuration,including basal I1 stacking faults(SFs)and<c+a>dislocations,has been established in extension twins.As the strain reaches 7%,the volume fraction of extension twins increases to more than 90%at which point high dense I1 SFs and<c+a>dislocations occur.After aging for 2 h at 150℃for the 7%strained sample,masses of basal I1 SFs and<c+a>dislocations remain in the extension twins and can act as effective nucleation sites and solute fast-diffusion channels for continuous precipitates.Consequently,the precipitates in extension twins become highly dense. 展开更多
关键词 Magnesium alloy extension twin DISLOCATION Stacking fault Precipitation
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Validation of user-friendly models predicting extracapsular extension in prostate cancer patients
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作者 Leandro Blas Masaki Shiota +7 位作者 Shohei Nagakawa Shigehiro Tsukahara Takashi Matsumoto Ken Lee Keisuke Monji Eiji Kashiwagi Junichi Inokuchi Masatoshi Eto 《Asian Journal of Urology》 CSCD 2023年第1期81-88,共8页
Objective:There are many models to predict extracapsular extension(ECE)in patients with prostate cancer.We aimed to externally validate several models in a Japanese cohort.Methods:We included patients treated with rob... Objective:There are many models to predict extracapsular extension(ECE)in patients with prostate cancer.We aimed to externally validate several models in a Japanese cohort.Methods:We included patients treated with robotic-assisted radical prostatectomy for prostate cancer.The risk of ECE was calculated for each patient in several models(prostate side-specific and non-side-specific).Model performance was assessed by calculating the receiver operating curve and the area under the curve(AUC),calibration plots,and decision curve analyses.Results:We identified ECE in 117(32.9%)of the 356 prostate lobes included.Patients with ECE had a statistically significant higher prostate-specific antigen level,percentage of positive digital rectal examination,percentage of hypoechoic nodes,percentage of magnetic resonance imaging nodes or ECE suggestion,percentage of biopsy positive cores,International Society of Urological Pathology grade group,and percentage of core involvement.Among the sidespecific models,the Soeterik,Patel,Sayyid,Martini,and Steuber models presented AUC of 0.81,0.78,0.77,0.75,and 0.73,respectively.Among the non-side-specific models,the memorial Sloan Kettering Cancer Center web calculator,the Roach formula,the Partin tables of 2016,2013,and 2007 presented AUC of 0.74,0.72,0.64,0.61,and 0.60,respectively.However,the 95%confidence interval for most of these models overlapped.The side-specific models presented adequate calibration.In the decision curve analyses,most models showed net benefit,but it overlapped among them.Conclusion:Models predicting ECE were externally validated in Japanese men.The side-specific models predicted better than the non-side-specific models.The Soeterik and Patel models were the most accurate performing models. 展开更多
关键词 PROGNOSIS Prostate cancer NOMOGRAM Extracapsular extension
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COMPARISON OF HOMOLOGIES AND AUTOMATIC EXTENSIONS OF INVARIANT DISTRIBUTIONS
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作者 陈阳洋 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1561-1570,共10页
Let G be a reductive Nash group,acting on a Nash manifold X.Let Z be a G-stable closed Nash submanifold of X and denote by U the complement of Z in X.Letχbe a character of G and denote by g the complexified Lie algeb... Let G be a reductive Nash group,acting on a Nash manifold X.Let Z be a G-stable closed Nash submanifold of X and denote by U the complement of Z in X.Letχbe a character of G and denote by g the complexified Lie algebra of G.We give a sufficient condition for the natural linear map H_(k)(g,S(U)×χ)→H_k(g,S(X)×χ)between the Lie algebra homologies of Schwartz functions to be an isomorphism.For k=0,by considering the dual,we obtain the automatic extensions of g-invariant(twisted by-χ)Schwartz distributions. 展开更多
关键词 Schwartz functions Lie algebra homology Hausdorffness Schwartz distributions automatic extensions
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An Introduction to the Theory of Field Extensions
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作者 Saviour Chibeti Iness Kyapwanyama +1 位作者 Henry M. Phiri Jeromy Kalunga 《Advances in Pure Mathematics》 2023年第2期103-132,共30页
This paper unfolds and reviews the theory of abstract algebra, field extensions and discusses various kinds of field extensions. Field extensions are said to be algebraic or transcendental. We pay much attention to al... This paper unfolds and reviews the theory of abstract algebra, field extensions and discusses various kinds of field extensions. Field extensions are said to be algebraic or transcendental. We pay much attention to algebraic extensions. Finally, we construct finite extensions of Q and finite extensions of the function field over finite field F<sub>p </sub>using the notion of field completion, analogous to field extensions. With the study of field extensions, considering any polynomial with coefficients in the field, we can find the roots of the polynomial, and with the notion of algebraically closed fields, we have one field, F, where we can find the roots of any polynomial with coefficients in F. 展开更多
关键词 Fields extension Fields Algebraic and Transcendental extension Algebraic Closure Algebraically Closed Field Absolute Value COMPLETION P-Adic Field and Field of Formal Laurent Series
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IMPROVED REGULARITY OF HARMONIC DIFFEOMORPHIC EXTENSIONS ON QUASIHYPERBOLIC DOMAINS
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作者 王壮 徐海清 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期373-386,共14页
Let X be a Jordan domain satisfying certain hyperbolic growth conditions.Assume that φ is a homeomorphism from the boundary ?X of X onto the unit circle.Denote by h the harmonic diffeomorphic extension of φ from X o... Let X be a Jordan domain satisfying certain hyperbolic growth conditions.Assume that φ is a homeomorphism from the boundary ?X of X onto the unit circle.Denote by h the harmonic diffeomorphic extension of φ from X onto the unit disk.We establish the optimal Orlicz-Sobolev regularity and weighted Sobolev estimate of h.These generalize the Sobolev regularity of h in [A.Koski,J.Onninen,Sobolev homeomorphic extensions,J.Eur.Math.Soc.23(2021) 4065-4089,Theorem 3.1]. 展开更多
关键词 Poisson extension Orlicz-Sobolev homeomorphisms weighted Sobolev homeomorphisms quasihyperbolic domains
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ON THE FIGIEL TYPE PROBLEM AND EXTENSION OFε-ISOMETRY BETWEEN UNIT SPHERES
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作者 刘锐 尹际富 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1503-1517,共15页
This paper studies two isometric problems between unit spheres of Banach spaces.In the first part,we introduce and study the Figiel type problem of isometric embeddings between unit spheres.However,the classical Figie... This paper studies two isometric problems between unit spheres of Banach spaces.In the first part,we introduce and study the Figiel type problem of isometric embeddings between unit spheres.However,the classical Figiel theorem on the whole space cannot be trivially generalized to this case,and this is pointed out by a counterexample.After establishing this,we find a natural necessary condition required by the existence of the Figiel operator.Furthermore,we prove that when X is a space with the T-property,this condition is also sufficient for an isometric embedding T:S_(X)→S_(Y) to admit the Figiel operator.This answers the Figiel type problem on unit spheres for a large class of spaces.In the second part,we consider the extension of bijectiveε-isometries between unit spheres of two Banach spaces.It is shown that every bijectiveε-isometry between unit spheres of a local GL-space and another Banach space can be extended to be a bijective 5ε-isometry between the corresponding unit balls.In particular,whenε=0,this recovers the MUP for local GL-spaces obtained in[40]. 展开更多
关键词 unit spheres isometric embedding Figiel type problem ε-isometry extension
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Temporal Convolutional Network for Speech Bandwidth Extension
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作者 Chundong Xu Cheng Zhu +1 位作者 Xianpeng Ling Dongwen Ying 《China Communications》 SCIE CSCD 2023年第11期142-150,共9页
In the field of speech bandwidth exten-sion,it is difficult to achieve high speech quality based on the shallow statistical model method.Although the application of deep learning has greatly improved the extended spee... In the field of speech bandwidth exten-sion,it is difficult to achieve high speech quality based on the shallow statistical model method.Although the application of deep learning has greatly improved the extended speech quality,the high model complex-ity makes it infeasible to run on the client.In order to tackle these issues,this paper proposes an end-to-end speech bandwidth extension method based on a temporal convolutional neural network,which greatly reduces the complexity of the model.In addition,a new time-frequency loss function is designed to en-able narrowband speech to acquire a more accurate wideband mapping in the time domain and the fre-quency domain.The experimental results show that the reconstructed wideband speech generated by the proposed method is superior to the traditional heuris-tic rule based approaches and the conventional neu-ral network methods for both subjective and objective evaluation. 展开更多
关键词 speech bandwidth extension temporal convolutional networks time-frequency loss
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Present Situation of Rural Regional Development and Agricultural Extension Policy
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作者 Xinran ZHAO 《Asian Agricultural Research》 2023年第8期35-37,40,共4页
The formulation of agricultural extension policy and the development of rural regional economy present the relationship of mutual existence,mutual influence and mutual promotion.Therefore,it is necessary to study the ... The formulation of agricultural extension policy and the development of rural regional economy present the relationship of mutual existence,mutual influence and mutual promotion.Therefore,it is necessary to study the agricultural extension policy according to the current situation of rural regional development.Agricultural technology extension system is an organization set up at county and township levels to provide farmers with scientific research achievements and practical technical services on planting,animal husbandry,fishery,forestry,agricultural machinery and water conservancy,and it is an important carrier for implementing the strategy of developing agriculture through science and technology.On the basis of expounding the value and significance of rural regional economic development,this paper analyzes the problems existing in China s rural regional development from the aspects of rural infrastructure and public services,rural labor force s cultural and scientific level,rural grass-roots extension system,etc.,and puts forward corresponding measures against the problems.This study has certain theoretical reference value for promoting the all-round development of China s rural economy and realizing the great strategy of rural revitalization in China. 展开更多
关键词 Rural regional development Rural public services Rural infrastructure Agricultural technology extension system Agricultural extension policy
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