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Gradient-Guided Assembly Instruction Relocation for Adversarial Attacks Against Binary Code Similarity Detection
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作者 Ran Wei Hui Shu 《Computers, Materials & Continua》 2026年第1期1372-1394,共23页
Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Althoug... Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Although adversarial examples can strategically undermine the accuracy of BCSD models and protect critical code,existing techniques predominantly depend on inserting artificial instructions,which incur high computational costs and offer limited diversity of perturbations.To address these limitations,we propose AIMA,a novel gradient-guided assembly instruction relocation method.Our method decouples the detection model into tokenization,embedding,and encoding layers to enable efficient gradient computation.Since token IDs of instructions are discrete and nondifferentiable,we compute gradients in the continuous embedding space to evaluate the influence of each token.The most critical tokens are identified by calculating the L2 norm of their embedding gradients.We then establish a mapping between instructions and their corresponding tokens to aggregate token-level importance into instructionlevel significance.To maximize adversarial impact,a sliding window algorithm selects the most influential contiguous segments for relocation,ensuring optimal perturbation with minimal length.This approach efficiently locates critical code regions without expensive search operations.The selected segments are relocated outside their original function boundaries via a jump mechanism,which preserves runtime control flow and functionality while introducing“deletion”effects in the static instruction sequence.Extensive experiments show that AIMA reduces similarity scores by up to 35.8%in state-of-the-art BCSD models.When incorporated into training data,it also enhances model robustness,achieving a 5.9%improvement in AUROC. 展开更多
关键词 Assembly instruction relocation adversary attack binary code similarity detection
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Determination of thermodynamic properties in full composition range of Ti-Al binary melts based on atom and molecule coexistence theory 被引量:2
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作者 Sheng-chao DUAN Xiao SHI +2 位作者 Wen-sheng YANG Han-jie GUO Jing GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第6期1256-1264,共9页
The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for ca... The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N_(i)of structural units in Ti-Al system based on the atom and molecule coexistence theory(AMCT).Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution(0x_(Ti)0.01)of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973,2073,2173,and 2273 K.The standard molar Gibbs free energy change of dissolving pure liquid element i(l)for forming 1%(mass fraction)element i in Ti-Al binary melts further was deduced.With the aid of this model,meanwhile,the determined excess thermodynamic properties,such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated. 展开更多
关键词 ti-al binary system Ti Al activity coefficient thermodynamic model mass action concentration atom and molecule coexistence theory
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Variable binaries and variables in binaries in the Binary star DataBase
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作者 Dana Kovaleva Oleg Malkov Pavel Kaygorodov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期7-12,共6页
The Binary star DataBase(BDB, http://bdb.inasan.ru) combines data from catalogs of binary and multiple stars of all observational types. There is a number of ways for variable stars to form or to be a part of binary o... The Binary star DataBase(BDB, http://bdb.inasan.ru) combines data from catalogs of binary and multiple stars of all observational types. There is a number of ways for variable stars to form or to be a part of binary or multiple systems. We describe how such stars are represented in the database. 展开更多
关键词 astronomical data bases-stars BINARIES general-stars VARIABLES GENERAL
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The new RS CVn binary V1034 Her revisited and the orbital period—activity relation of short-period RS CVn binaries using photometric distortion amplitude
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作者 Li-Yun Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第4期433-442,共10页
This paper presents new CCD BV RI light curves of the newly discovered RS CVn eclipsing binary V1034 Her in 2009 and 2010, the shapes of which are different from previously published results. They show an asymmetric o... This paper presents new CCD BV RI light curves of the newly discovered RS CVn eclipsing binary V1034 Her in 2009 and 2010, the shapes of which are different from previously published results. They show an asymmetric outside eclipse, and we try to use a spot model to explain the phenomenon. Using the Wilson-Devinney program with a one-spot or two-spot model, photometric solutions of the system and starspot parameters were derived. Comparing the two results shows that the case of two spots is more successful in reproducing light-curve distortions. Looking at all the spot longitudes, the trend is towards active longitude belts and each active longitude belt may switch. Comparing the light curves from 2009 and 2010, we can see that the light curve changes over the long time scale of a year, especially in phase 0.25. In addition, we also collected the values of the maximum amplitudes of photometric distortion of the short-period RS CVn binary. We found for the first time that there is a trend of increasing activity with decreasing orbital period. Finally, fitting all available light minimum times including our newly obtained ones with a polynomial function confirmed that the orbital period of V1034 Her increased. 展开更多
关键词 stars: binaries: late-type stars: binaries: eclipsing stars: individuals (V1034 Her) stars: spots
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烧结温度对Ti-Al结合剂聚晶金刚石性能的影响
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作者 董清妍 王慧可 +3 位作者 郑皓宇 汤黎辉 张群飞 肖长江 《粉末冶金技术》 北大核心 2025年第5期641-646,共6页
以平均粒径5μm金刚石微粉为原料,Ti粉和A1粉为结合剂,使用六面顶压机在高温(1350~1550℃)、高压(5.5 GPa)下制备聚晶金刚石,研究了烧结温度对聚晶金刚石物相组成、微观结构和力学性能的影响。结果表明:在高温高压下,Ti和A1分别与金刚... 以平均粒径5μm金刚石微粉为原料,Ti粉和A1粉为结合剂,使用六面顶压机在高温(1350~1550℃)、高压(5.5 GPa)下制备聚晶金刚石,研究了烧结温度对聚晶金刚石物相组成、微观结构和力学性能的影响。结果表明:在高温高压下,Ti和A1分别与金刚石完全反应生成TiC和Al_(4)C_(3),聚晶金刚石主要由金刚石、TiC和Al_(4)C_(3)组成。随烧结温度的升高,聚晶金刚石的相对密度、磨耗比、维氏硬度、断裂韧性均出现先增加后降低的现象。当烧结温度为1500℃时,金刚石被结合剂紧密包裹,颗粒之间无明显孔洞,聚晶金刚石有最大的相对密度、维氏硬度、断裂韧性和磨耗比,分别为98.8%、54.2 GPa、5.23 MPa·m^(1/2)和6210。 展开更多
关键词 聚晶金刚石 高温高压 ti-al结合剂 微观结构 力学性能
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Ti-Al焊接数值模拟研究现状
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作者 丁镜之 袁江 +2 位作者 刘潇潇 吕昊 张睿 《世界有色金属》 2025年第18期59-61,共3页
为解决钛铝异种金属焊接实验过程中难以观察到的材料流动状况和产热传热行为,数值模拟可以提供更直观和全面的方法,本文归纳了国内外研究学者对于钛铝异种金属焊接中利用数值模拟的几类研究。分别为针对爆炸焊接进行数值模拟、IMCs生长... 为解决钛铝异种金属焊接实验过程中难以观察到的材料流动状况和产热传热行为,数值模拟可以提供更直观和全面的方法,本文归纳了国内外研究学者对于钛铝异种金属焊接中利用数值模拟的几类研究。分别为针对爆炸焊接进行数值模拟、IMCs生长机理类数值模拟等。 展开更多
关键词 铝合金 钛合金 ti-al焊接 数值模拟
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Preparation of Ti-Al Alloys by Aluminothermic Reduction with MgF_(2)Addition
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作者 Tian Zhenyun Chen Liangbin +3 位作者 Song Jingjing Kang Jialong Mao Hongxia Qiu Guibao 《稀有金属材料与工程》 北大核心 2025年第7期1678-1686,共9页
The Ti-Al alloy was synthesized using the aluminothermic reduction of TiO_(2),with CaO and MgF_(2)serving as flux components.Investigations were conducted to ascertain the effects of MgF_(2)content on the alloy-slag s... The Ti-Al alloy was synthesized using the aluminothermic reduction of TiO_(2),with CaO and MgF_(2)serving as flux components.Investigations were conducted to ascertain the effects of MgF_(2)content on the alloy-slag separation,alloy microstructure,composition,phase constitution,overall alloy yield,and aluminothermic reduction of TiO_(2).Results indicate that MgF_(2)enhances the separation of the alloy from slag and promotes the formation of the TiAl phase within the alloy matrix.Nevertheless,an overabundance of MgF_(2)reduces the interfacial tension between the Al reductant and the slag,leading to significant loss of Al.This adversely affects alloy-slag separation,escalates the incorporation of oxide inclusions in the alloy,and severely reduces the recovery rate of alloy.Concurrently,the alloy has a phase transition from TiAl to Ti_(3)Al.The optimum condition for alloy-slag separation and alloy integrity is realized at the MgF_(2)content of 10wt%.Kinetic analysis at this flux ratio determines the activating energy for the Al-TiO_(2)-CaO-MgF_(2)system,which is 409.729 kJ/mol,and the order of kinetics is n=0.38. 展开更多
关键词 MgF_(2) ti-al alloy alloy-slag separation aluminothermic reduction
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Synergistic properties of the binary mixed system of natural green surfactants:Camellia oleifera saponin and sodium cocoyl glycinate
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作者 Yawen Li Weixin Li +3 位作者 Fenglun Zhang Shihong Ma Jianxin Jiang Liwei Zhu 《日用化学工业(中英文)》 北大核心 2025年第7期831-843,共13页
Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleif... Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleifera saponin(COS)was purified using AB-8 macroporous adsorption resin,and its composition and structure were analyzed.The effects of different mole fractions of COS(αCOS)on surface tension(γ),oil-water interfacial tension(IFT),emulsification,and foam properties of COS-SCG binary mixed systems were investigated in mixtures of SCG with purified COS.The stability ofγand foamability under diverse environmental conditions were also discussed.The results indicated that the COS-SCG system exhibited remarkable surface-active synergism.The minimum critical micelle concentration(cmc)of the mixed system was lower than that of SCG,and adding a small mole fraction of COS(1%-2%)induced a synergistic reduction ofγ.Specifically,the cmc andγwere 2.50×10-4 mol/L and 23.1 mN/m forαCOS=1%,respectively.The system exhibited exceptional IFT reduction capacity,achieving a minimum value of 1.42 mN/m atαCOS=10%.The mixed system reached a foaming volume(atαCOS=50%)and foam stability(atαCOS=75%)were 51.0 mL and 97.37%,respectively.Microscopic analysis further confirmed these outstanding foam properties.Moreover,the COS-SCG system displayed reducedγwith enhanced foaming volume under elevated temperatures(35-75℃)and salinity(0-20 g/L).However,acidic conditions and hard water compromised bothγstability and foamability. 展开更多
关键词 SAPONIN sodium cocoyl glycinate binary mixed system synergism interfacial tension foam properties
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Impact factor analysis of less developed farmers'livelihood strategies based on the binary Logit model
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作者 HE Li-Long TAN Hao-Wen +1 位作者 GUO Jin-Ting XIA Ting-Fu 《四川大学学报(自然科学版)》 北大核心 2025年第5期1265-1280,共16页
In this paper,based on the structure-behavior coupling paradigm,we propose the concept of deviation of central town to describe the geography-market distance between farmers and the central regional town.Using the sur... In this paper,based on the structure-behavior coupling paradigm,we propose the concept of deviation of central town to describe the geography-market distance between farmers and the central regional town.Using the survey data from farmers in a poverty-stricken village in Western China,the impact of deviation of central town on farmers'livelihood strategies is analyzed.The results indicate that farmers exhibit spatial heterogeneity in their livelihood strategies.Those with low deviation show a strong inclination towards working in urban areas,while those with high deviation tend to integrate into rural industries.The deviation of central town influences farmers'livelihood strategies through the information effect,which is also affected by the level of rural infrastructure and public services,labor force structure and assistance policies.The obtained results are expected to provide guidance for promoting the integration of farmers into the urban-rural economic cycle based on sustainable livelihoods and connecting poverty alleviation with rural revitalization. 展开更多
关键词 Deviation of central town Livelihood strategy binary Logit model
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Analysis of a Double-lined Spectroscopic Binary System Using LAMOST and TESS Data
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作者 Daoye Yang Jianrong Shi +4 位作者 Ali Esamdin Chunqian Li Xiang-Lei Chen Rivkat Karimov Shuhrat A.Ehgamberdiev 《Research in Astronomy and Astrophysics》 2025年第9期123-131,共9页
We present a detailed analysis of a double-lined spectroscopic binary system,Bo Gem,using data obtained from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)and the Transiting Exoplanet Survey Sat... We present a detailed analysis of a double-lined spectroscopic binary system,Bo Gem,using data obtained from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)and the Transiting Exoplanet Survey Satellite(TESS).By applying spectral disentangling techniques to the LAMOST Medium Resolution Spectra,we determine the orbital parameters,including the orbital period of P=4.0689 days,and semimajor axis of a=14.90±0.04 R_(⊙).The mass ratio between the two components is found to be q=0.198±0.006,with an inclination of i=82°.3±0°.13.The photometric data from TESS revealed periodic light variations due to the eclipsing nature of the system,allowing for the determination of the primary star’s radius as R_(1)=1.68±0.03 R_(⊙)and the secondary star’s radius as R_(2)=3.68±0.04 R_(⊙).The effective temperatures of the primary and secondary stars are measured to be T_(eff,1)=9705±50 K and T_(eff,2)=5830±22 K,respectively.By analyzing the disentangled spectra,we determined the stellar atmospheric parameters—including surface gravity and metallicity of both stars.These results not only confirm the double-lined spectroscopic binary status of Bo Gem,but also underscore its value as an important system for testing and refining stellar evolution models. 展开更多
关键词 (stars:)binaries eclipsing-(stars:)binaries spectroscopic-(stars:)binaries general
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Transcending Binary Opposition: Exploring the Path to Harmonious Coexistence of Humanity From a Philosophical Perspective
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作者 CUI Weicheng 《Philosophy Study》 2025年第2期49-60,共12页
This paper analyzes binary opposition thinking,dominant in Western societies since ancient Greece,its prevalence in philosophy,international relations,etc.While it influenced science and technology,it also caused conf... This paper analyzes binary opposition thinking,dominant in Western societies since ancient Greece,its prevalence in philosophy,international relations,etc.While it influenced science and technology,it also caused conflicts,hindering the sustainable development of humanity.The paper explores the“binary co-existence”philosophy from Eastern thought.It explains its basis,applications,and significance in overcoming global social issues currently encountered.This philosophy emphasizes mutual dependence of opposites,offering solutions to global challenges.The paper stresses the urgency of shifting from binary opposition to binary co-existence,crucial for resolving conflicts and promoting sustainable development.It discusses ways like education and media to achieve this for global harmony. 展开更多
关键词 binary opposition binary co-existence thinking paradigm global challenges sustainable development TRANSFORMATION
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Revised Orbital,Physical,Stability,and Habitability Parameters of the Binary System HD 25811 Using Gaia Observations
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作者 Hassan B.Haboubi Mashhoor A.Al-Wardat +5 位作者 Ahmad A.Abushattal Maximiliano Dirk Hatem Widyan Naufa Nazar Joshua V.Thomji Suhail Masda 《Research in Astronomy and Astrophysics》 2025年第12期147-156,共10页
Al-Wardat's method is used in this research to analyze the two components of the HD 25811 binary system,which combines the results of speckle interferometry with the astrometric data to construct the synthetic spe... Al-Wardat's method is used in this research to analyze the two components of the HD 25811 binary system,which combines the results of speckle interferometry with the astrometric data to construct the synthetic spectral energy distribution of the system.The method results in the effective temperatures at 7100±50 K for component A and 7000±50 K for component B,while their masses measure as 1.65±0.15M_(⊙)for component A and1.58±0.14M_(⊙)for component B.The system exists at an estimated age of 0.794 Gyr,while both stars remain in their initial subgiant evolutionary phase.The evolutionary tracks together with isochrones for Z=0.03 validate that the system components share both their origin and chemical compositions.The orbital analysis shows that the system has a period of 15.97 yr and an eccentricity of 0.713,while the total system mass amounts to3.65±0.49 M_(⊙).We detailedly analyze the system's orbital dynamics to assess planetary stability and habitability zones,which lead to the dynamics of circumbinary(P-type)and circumstellar(S-type)orbits using empirical criteria,revealing large regions in which planetary orbits remain dynamically stable.Luminosities and effective temperatures of each stellar component are used to determine their habitable zones. 展开更多
关键词 (stars:)binaries(including multiple):close (stars:)binaries:visual (stars:)binaries:spectroscopic stars:evolution Astrometry and Celestial Mechanics
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UV Flux Variation Study in Contact Binary VW Cephei
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作者 Anurag Baruah Mayukh Pahari 《Research in Astronomy and Astrophysics》 2025年第10期262-271,共10页
Despite many attempts,the origin of UV emission line and continuum in contact binary stars remains unclear.We present a substantial UV spectroscopic analysis of VW Cephei,a late-type contact binary system,using 46 low... Despite many attempts,the origin of UV emission line and continuum in contact binary stars remains unclear.We present a substantial UV spectroscopic analysis of VW Cephei,a late-type contact binary system,using 46 lowresolution spectra from the International Ultraviolet Explorer in the wavelength range 1150-1978À.By modeling continuum and emissions lines in individual spectra,we report the significant detection of O Ⅲ](1660 and 1666À)and Si Ⅳ(1393 and 1402À)line complexes.We observe that UV fluxes for both continuum and emission lines like C Ⅳ,O Ⅲ],C Ⅱ and Si Ⅳ vary significantly(fractional rms variability up to 45%)from hours to years.In addition,line widths also change by hundreds of km s^(-1).The UV flux variabilities observed in the continuum bands and line emissions are uncorrelated.However,most of the flux values follow the binary orbital period observed from optical data.Our analysis indicates that,while the variation in continuum flux may be attributed to a heated photosphere,the line width measurements indicate that the emission lines are likely formed in the dynamical clouds associated with Roche lobe overflow.We estimate the mass transfer rate of M=(0.82±0.01)×10^(-7)M_(⊙)yr^(-1)from UV line fluxes,which is in good agreement with optical studies. 展开更多
关键词 techniques spectroscopic-(stars )binaries eclipsing-ultraviolet STARS
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Superior Energy Storage Performance in Crosslinked Binary Polymers at High Temperatures Via Confnement Effect
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作者 Yongbin Liu Yating Xu +6 位作者 Jinghui Gao Jingzhe Xu Ming Wu Zhengwei Liu Yilong Wang Xiaojie Lou Lisheng Zhong 《Energy & Environmental Materials》 2025年第2期201-206,共6页
High-temperature performance of energy storage dielectric polymers is desired for many electronics and electrical applications,but the trade-off between energy density and temperature stability remains fundamentally c... High-temperature performance of energy storage dielectric polymers is desired for many electronics and electrical applications,but the trade-off between energy density and temperature stability remains fundamentally challenging.Here,we report a general material design strategy to enhance energy storage performance at high temperatures by crosslinking a polar polymer and a high glass-transition temperature polymer as a crosslinked binary blend.Such crosslinked binary polymers display a temperature-insensitive and high energy density behavior of about6.2~8.5 J cm^(-3) up to 110℃,showing a significant enhancement in thermal resistant properties and consequently outperforming most of the other ferroelectric polymers.Further microstructural investigations reveal that the improved thermal stability stems from the confinement effect on conformational motion of the crosslinking network,which is evidenced by the increased rigid amorphous fraction and steady intermolecular distance of amorphous regions from temperature-dependent X-ray diffraction results.Our findings provide a general and straightforward strategy to attain temperature-stable,high-energy-density polymer-based dielectrics for energy storage capacitors. 展开更多
关键词 crosslinking binary DIELECTRIC energy storage high temperature polymer
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Analysis of the consistency status and influencing factors of binary symptom assessment in patients with heart failure
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作者 Chen-Ming Li Gu-Yue Yan +2 位作者 Lu Yu Qi Zhang Qing Wu 《Nursing Communications》 2025年第22期1-12,共12页
Background:To investigate the consistency level of binary symptom assessment in patients with heart failure and their primary caregivers,and to analyze the related factors influencing consistency.Methods:By using the ... Background:To investigate the consistency level of binary symptom assessment in patients with heart failure and their primary caregivers,and to analyze the related factors influencing consistency.Methods:By using the convenience sampling method,patients with heart failure and their main caregivers in the Department of Cardiology of a tertiary hospital in Suzhou from May to November 2023 were selected as the research subjects.The HFSS scale was used for data collection.The paired t-test or paired Wilcoxon test was used to evaluate the differences in the binary symptom assessment scores of heart failure.The intraclass correlation coefficient was used to assess the consistency level of the binary symptom assessment.The Pearson correlation test was used to examine the correlation of the binary symptom assessment.Regression analysis was employed to explore the factors related to the consistency assessment.Results:A total of 103 pairs of valid questionnaires were collected.The consistency levels of symptom evaluations in patients with heart failure and their primary caregivers were statistically significant(P<0.05).The most frequently reported and severe symptom by patients with heart failure and their primary caregivers is shortness of breath during activity.Both have a high consensus on the severity and urgency of most heart failure symptoms.The patient’s gender,body mass index,number of children,history of diabetes,number of comorbidities,mean arterial pressure,LVEF,number of stents,whether a defibrillator was implanted,as well as the gender,marital status,education level,relationship with the patient,care time,whether they lived together,and communication and interaction situation of the main caregiver were the influencing factors for the consistency of binary symptom assessment of heart failure(P<0.05).Conclusion:The degree of consistency in binary symptom assessment between patients with heart failure and their primary caregivers was moderate or higher,which emphasizes the importance of including binary groups in clinical assessment. 展开更多
关键词 heart failure symptom assessment binary consistency study
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NR Cam:A New Active Low Mass-ratio Contact Binary with a Potential Third Companion
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作者 Jie Wei Chao-Yue Li +8 位作者 Lin-Qiao Jiang Jie Zheng Kai Huang Yi-Man Liu Shuang Gou Mu-Lan Deng Li-Jun Mei Lin Cao Xiao-Yu Long 《Research in Astronomy and Astrophysics》 2025年第9期213-225,共13页
This study presents a detailed photometric and spectroscopic analysis of the W UMa-type binary NR Cam,using data from the Transiting Exoplanet Survey Satellite(TESS)and ground-based observations.The light curves exhib... This study presents a detailed photometric and spectroscopic analysis of the W UMa-type binary NR Cam,using data from the Transiting Exoplanet Survey Satellite(TESS)and ground-based observations.The light curves exhibit significant variable,with a negative correlation between the brightness of the two maxima—a characteristic of W UMa-type binaries typically attributed to magnetic activity.To explain this behavior,we incorporated a starspot model into our Wilson–Devinney analysis.Our results confirm that NR Cam is a W-subtype,moderately contact binary with a low mass ratio of q=5.75(±0.03)and a fill-out factor of f=33.4(±3.1)%.We also analyzed the orbital period variation using all available times of minima.The resulting O−C diagram reveals a long-term decreasing trend in the orbital period at a rate of dP/dt=−5.18(±0.02)×10^(-8) day yr^(-1),superimposed with a periodic oscillation characterized by an amplitude of A_(3)=0.0019(±0.0001)day and an oscillation period of P_(3)=7.776(±0.003)yr.The long-term decrease is likely due to mass transfer between the binary components,with an estimated mass transfer rate of dM_(2)/dt=1.33(±0.01)×10^(-8)M_(⊙)yr^(-1).The periodic oscillations are likely driven by the light-travel time effect caused by a tertiary companion,with a minimum mass of M_(3)=0.0956(1)M_(⊙)and a maximum separation of 3.841(6)au.Additionally,we considered the possibility that the periodic variation could result from changes in the gravitational quadrupole moment due to magnetic activity cycles,as described by the Applegate mechanism.Our findings confirm that NR Cam is an active binary system,where magnetic activity plays a significant role in its orbital evolution.These results contribute to our understanding of the magnetic dynamics and evolutionary processes in contact binary systems. 展开更多
关键词 (stars:)binaries(including multiple) close-(stars:)binaries eclipsing-(stars:)starspots
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Modelling Microsegregation of Binary Alloy During Solidification
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作者 Tongzhao Gong Shuting Cao +4 位作者 Weiye Hao Weiqi Fan Yun Chen Xing-Qiu Chen Dianzhong Li 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1628-1636,共9页
This work studies the impact of the carbon diffusion on the growth kinetics of austenite and the solute segregation,by utilizing the phase-field(PF)method to simulate the solidification of a Fe-C binary alloy.It is re... This work studies the impact of the carbon diffusion on the growth kinetics of austenite and the solute segregation,by utilizing the phase-field(PF)method to simulate the solidification of a Fe-C binary alloy.It is revealed that increasing the ratio of the carbon diffusion coefficient in solid to that in liquid is advantageous in reducing the solute segregation,and a novel microsegregation model is developed based on the quantitative analysis of the results from PF simulations.The simplified one-dimensional diffusion simulation is employed to analyse the quantitative relationship between the parameters of the proposed microsegregation model and the properties of materials.The universality and reliability of the new microsegregation model are then validated by comparing with the experimental data of various alloy systems.These findings contribute to our comprehension of the fundamental theory of solidification and also provide a potential and promising approach to controlling the solidification microstructure. 展开更多
关键词 binary alloy SOLIDIFICATION MICROSEGREGATION Phase-field method Solid back diffusion
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Space-Borne Interferometers to Detect Thousands of Memory Signals Emitted by Stellar-Mass Binary Black Holes
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作者 Shaoqi Hou Zhi-Chao Zhao +1 位作者 Zhoujian Cao Zong-Hong Zhu 《Chinese Physics Letters》 2025年第10期323-330,共8页
The gravitational memory effect manifests gravitational nonlinearity,degenerate vacua,and asymptotic symmetries;its detection is considered challenging.We propose using a space-borne interferometer to detect memory si... The gravitational memory effect manifests gravitational nonlinearity,degenerate vacua,and asymptotic symmetries;its detection is considered challenging.We propose using a space-borne interferometer to detect memory signals from stellar-mass binary black holes(BBHs),typically targeted by ground-based detectors.We use DECIGO detector as an example.Over 5 years,DECIGO is estimated to detect approximately 2,036 memory signals(SNRs>3)from stellar-mass BBHs.Simulations used frequency-domain memory waveforms for direct SNR estimation.Predictions utilized a GWTC-3 constrained BBH population model(Power law+Peak mass,DEFAULT spin,Madau-Dickinson merger rate).The analysis used conservative lower merger rate limits and considered orbital eccentricity.The high detection rate stems from strong memory signals within DECIGO’s bandwidth and the abundance of stellar-mass BBHs.This substantial and conservative detection count enables statistical use of the memory effect for fundamental physics and astrophysics.DECIGO exemplifies that space interferometers may better detect memory signals from smaller mass binaries than their typical targets.Detectors in lower frequency bands are expected to find strong memory signals from∼10^(4)M⊙binaries. 展开更多
关键词 space borne interferometer detect memory signals gravitational memory effect decigo detector binary black holes bbhs typically stellar mass binary black holes signal noise ratio
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New Orbital Parameters of 850 Wide Visual Binary Stars and Their Statistical Properties
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作者 Igor Izmailov Maxim Khovritchev 《Research in Astronomy and Astrophysics》 2025年第1期321-331,共11页
Based on positional observations and measurements of radial velocities,the orbits of 850 wide visual binary stars have been determined.The parameters of the log-normal distributions for the histograms of orbital perio... Based on positional observations and measurements of radial velocities,the orbits of 850 wide visual binary stars have been determined.The parameters of the log-normal distributions for the histograms of orbital periods,stellar masses,and semimajor axes in astronomical units have been obtained.The eccentricity histogram for binary stars with orbital periods less than 400 yr follows a normal distribution centered at e=0.545+/−0.029.For stars with longer periods,this distribution obeys the law f=2e,with accuracy to errors.The mass-to-luminosity relation for stars with well-determined masses is given by:log L_(⊙)=4.33 logM_(⊙)-0.11,where L_(⊙) and M_(⊙) are the luminosity and mass of the star in units of the solar luminosity and mass,respectively. 展开更多
关键词 (stars:)binaries visual-stars statistics-stars fundamental parameters
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The gravitational redshift effect of quantum matter waves passing a binary black hole
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作者 Qiyun Fu Tieyan Si 《Communications in Theoretical Physics》 2025年第4期95-101,共7页
We simulate the gravitational redshift of quantum matter waves with a long de Broglie wavelength by tracing particle beams along geodesics,when they propagate within the rotation plane of binary black holes.The angula... We simulate the gravitational redshift of quantum matter waves with a long de Broglie wavelength by tracing particle beams along geodesics,when they propagate within the rotation plane of binary black holes.The angular momentum of the binary black hole causes an asymmetric gravitational redshift distribution around the two black holes.The gravitational redshift changes the frequency of quantum matter waves and their wavelength,resulting in the different interference patterns of quantum matter waves with respect to different wavelengths.The interference pattern demonstrates strong contrast intensity and spatial order with respect to different wavelengths and the rotational angle of the binary black hole.A bright semicircular arc emerges from the interference pattern to bridge the two black holes,when they rotate to certain angles,which provides a theoretical understanding on the gravitational lensing effect of quantum matter waves. 展开更多
关键词 gravitational lensing the binary black hole wave inteference
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