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Volatile profile and multivariant analysis of Sanhuang chicken breast in combination with Chinese 5-spice blend and garam masala 被引量:4
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作者 Rani Andaleeb Danni Zhang +2 位作者 Shui Jiang Yin Zhang Yuan Liu 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期57-68,共12页
Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are rou... Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are routinely using spices in China and Pakistan,respectively.The flavour profiles of Sanhuang chicken breast(CB)and its blends with CS and GM were obtained by electronic nose(E-nose),solid-phase microextraction gas chromatography-mass spectrometry(SPME GC-MS)and GC-ion mobility spectrometry(GC-IMS).Principal component analysis(PCA)efficiently discriminated the aroma profiles of three chicken formulations.The GC-chromatographs revealed the significant aroma alterations of chicken breast meat after marination with spices.Aldehydes were the major contributors of chicken aroma,while most of the aromatic hydrocarbons were generated by spices.Almost all chicken key-compounds produced by oxidation reaction were either reduced or eliminated by marination,showing the antioxidation capacity of spices leading to meat preservation.GC-IMS is not only a rapid and comprehensive detection method,but also proved to be more sensitive than GC-MS.The substantial role of both traditional spices in enhancing flavour quality of chicken meat,and their exposure as functional ingredients in Chinese and Pakistan cuisines could lead to the cross-cultural meat trade opportunities. 展开更多
关键词 Chicken breast Chinese 5-spice blend Garam masala Volatile compounds Qualitative techniques multivariant analysis
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Grid-Based Path Planner Using Multivariant Optimization Algorithm
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作者 Baolei Li Danjv Lv +3 位作者 Xinling Shi Zhenzhou An Yufeng Zhang Jianhua Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第5期89-96,共8页
To solve the shortest path planning problems on grid-based map efficiently,a novel heuristic path planning approach based on an intelligent swarm optimization method called Multivariant Optimization Algorithm( MOA) an... To solve the shortest path planning problems on grid-based map efficiently,a novel heuristic path planning approach based on an intelligent swarm optimization method called Multivariant Optimization Algorithm( MOA) and a modified indirect encoding scheme are proposed. In MOA,the solution space is iteratively searched through global exploration and local exploitation by intelligent searching individuals,who are named as atoms. MOA is employed to locate the shortest path through iterations of global path planning and local path refinements in the proposed path planning approach. In each iteration,a group of global atoms are employed to perform the global path planning aiming at finding some candidate paths rapidly and then a group of local atoms are allotted to each candidate path for refinement. Further,the traditional indirect encoding scheme is modified to reduce the possibility of constructing an infeasible path from an array. Comparative experiments against two other frequently use intelligent optimization approaches: Genetic Algorithm( GA) and Particle Swarm Optimization( PSO) are conducted on benchmark test problems of varying complexity to evaluate the performance of MOA. The results demonstrate that MOA outperforms GA and PSO in terms of optimality indicated by the length of the located path. 展开更多
关键词 multivariant optimization algorithm shortest path planning heuristic search grid map optimality of algorithm
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面向高功率微波反演的高效时序神经网络算法研究
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作者 董纯志 黄志祥 冯乃星 《现代应用物理》 2025年第1期151-157,共7页
柱状等离子体阵列(columnar plasma array,CPA)被证明是一种极佳的高功率微波(high-power microwave,HPM)防护手段。然而,并非任一的HPM都足以激发CPA产生电磁屏蔽效应,因此提出并实现一种新的基于Encoder-Decoder框架和multivariate at... 柱状等离子体阵列(columnar plasma array,CPA)被证明是一种极佳的高功率微波(high-power microwave,HPM)防护手段。然而,并非任一的HPM都足以激发CPA产生电磁屏蔽效应,因此提出并实现一种新的基于Encoder-Decoder框架和multivariate attention机制的时间序列模型iiTransformer(improved iTransformer),对HPM与CPA间的复杂非线性过程进行数学建模并实现高功率微波反演。使用有限元方法(finite element method,FEM)完成算法仿真和数据采集,分别使用iiTransformer模型和ResNet-18模型实现了对高功率微波的反演推断。在iiTransformer模型中,利用Encoder和Decoder架构分别对数据序列和目标序列进行了多头自注意力处理,用于提取多变量在多通道中的关系依赖。相比之下,ResNet-18模型拟合数据序列所映射出的热图与目标序列间呈非线性映射关系。研究结果表明,所设计的iiTransformer模型具有很强的表征学习和非线性拟合能力,不仅泛化能力强而且鲁棒性好,在训练集上的损失为3.4548×10^(-7),在验证集上的损失达到了1.804×10^(-7),在测试集上的准确度为99.923%,远远高于ResNet-18模型的反演精度。 展开更多
关键词 高功率微波防护 柱状等离子体阵列 时间序列模型 Encoder-Decoder框架 multivariate attention机制
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An Empirical Analysis of Factors Influencing the Tourism Economy in Henan Province
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作者 Pingping WANG Liang ZHAO 《Asian Agricultural Research》 2025年第11期25-28,共4页
[Objectives]To study the factors influencing the tourism economy in Henan Province.[Methods]Using tourism-related data from Henan Province covering the period from 2000 to 2020,this study constructs a regression model... [Objectives]To study the factors influencing the tourism economy in Henan Province.[Methods]Using tourism-related data from Henan Province covering the period from 2000 to 2020,this study constructs a regression model based on multivariate statistical methods to investigate the determinants of the tourism economy.The dependent variable in the model is the domestic tourism revenue of Henan Province,while the independent variables comprise the number of tourist arrivals,total operational railway mileage,the number of travel agencies,and the per capita disposable income of urban residents.[Results]Both the total railway mileage and the per capita disposable income of urban residents are the primary factors influencing the development of Henan's tourism economy.[Conclusions]It is recommended to reduce uncertainty and liquidity constraints to mitigate residents'precautionary savings behavior,actively expand domestic demand to leverage tourism as an economic driver,and improve infrastructure to support tourism development. 展开更多
关键词 HENAN PROVINCE TOURISM ECONOMY Influencing factors MULTIVARIATE statistical analysis
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一个多元函数最值问题的推广
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作者 聂琳峻 《中等数学》 2025年第3期31-32,共2页
题目已知a、b、c∈[1,2].求证:a^(3)+b^(3)+c^(3)≤5abc.证明不妨设a≥b≥c.设f(a,b,c)=a^(3)+b^(3)+c^(3)-5abc.则f(a,b,1)-f(a,b,c)=1-c^(3)+5abc-5ab=(1-c)(1+c+c^(2)-5ab).
关键词 INEQUALITIES OPTIMIZATION multivariate functions proof techniques
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Co-Benefits of Antimicrobial Resistance Mitigation from China’s PM_(2.5)Air Pollution Reduction Between 2014-2020
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作者 Zhenchao Zhou Zejun Lin +9 位作者 Xinyi Shuai Xiaoliang Ba Chioma Achi Mark AHolmes Tong Xu Yingru Lu Yonghong Xiao Jianming Xu Baojing Gu Hong Chen 《Engineering》 2025年第2期243-251,共9页
The One Health concept acknowledges the importance of multiple dimensions in controlling antimicrobial resistance(AMR).However,our understanding of how anthropological,socioeconomic,and environmental factors drive AMR... The One Health concept acknowledges the importance of multiple dimensions in controlling antimicrobial resistance(AMR).However,our understanding of how anthropological,socioeconomic,and environmental factors drive AMR at a national level remains limited.To explore associations between potential contributing factors and AMR,this study analyzed an extensive database comprising 13 major antibioticresistant bacteria and over 30 predictors(e.g.,air pollution,antibiotic usage,economy,husbandry,public services,health services,education,diet,climate,and population)from 2014 to 2020 across China.The multivariate analysis results indicate that fine particulate matter with a diameter of 2.5 μm or less(PM_(2.5))is associated with AMR,accounting for 12%of the variation,followed by residents’income(10.3%)and antibiotic usage density(5.1%).A reduction in PM_(2.5)of 1 μg·m^(-3)is linked to a 0.17%decrease in aggregate antibiotic resistance(p<0.001,R^(2)=0.74).Under different scenarios of China’s PM_(2.5)airquality projections,we further estimated the premature death toll and economic burden derived from PM_(2.5)-related antibiotic resistance in China until 2060.PM_(2.5)-derived AMR is estimated to cause approximately 27000(95%confidence interval(CI):646848830)premature deaths and about 0.51(95%CI;0.12-0.92)million years of life lost annually in China,equivalent to an annual welfare loss of 8.4(95%CI;2.0-15.0)billion USD.Implementing the“Ambitious Pollution 1.5℃ Goals”scenario to reduce PM_(2.5)concentrations could prevent roughly 14000(95%CI;3324-26320)premature deaths—with a potential monetary value of 9.8(95%CI;2.2-17.6)billion USD—from AMR by 2060.These results suggest that reducing air pollution may offer co-benefits in the health and economic sectors by mitigating AMR. 展开更多
关键词 Antimicrobial resistance Air pollution Antibiotic usage Multivariable analysis Premature deaths NATIONWIDE
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Modeling and active disturbance rejection control of a tilt-rotor UAV
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作者 Victor-Gabriel Sánchez-Meza Yair Lozano-Hernández +2 位作者 Norma Lozada-Castillo Mario Ramírez-Neria Alberto Luviano-Juárez 《Control Theory and Technology》 2025年第3期563-577,共15页
In this article,the dynamical model and trajectory tracking problem for a tilt-rotor unmanned aerial vehicle is tackled through linear Active Disturbance Rejection Control(ADRC)applied on the tangent linearized system... In this article,the dynamical model and trajectory tracking problem for a tilt-rotor unmanned aerial vehicle is tackled through linear Active Disturbance Rejection Control(ADRC)applied on the tangent linearized system.To apply the ADRC scheme,it is considered the subsystem without the Y-axis component,which is differentially flat and whose flat outputs are obtained using the Kronecker matrix.Numerical assessment using as system parameters the ones of a scale prototype is provided to show the effectiveness of the proposal leading to accurate tracking results using admissible control values for an experimental scenario. 展开更多
关键词 Tilt-rotor ADRC Tangent linearization Multivariable systems Unmanned aerial vehicles
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Identification of the Nonlinear Distributions of Elements with Multifractal: A Case Study of the Er’renshan Ore Field, NW China
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作者 GONG Qiuli LIU Yanpeng 《Acta Geologica Sinica(English Edition)》 2025年第5期1509-1526,共18页
Geochemical surveys are essential for understanding the spatial distribution of ore-forming elements.However,these surveys often involve compositional data,the weight concentrations,which do not meet the requirements ... Geochemical surveys are essential for understanding the spatial distribution of ore-forming elements.However,these surveys often involve compositional data,the weight concentrations,which do not meet the requirements of statistical methods due to the closure effect.In this study,we applied an integrated approach combining compositional data,multifractal,and multivariate statistical analyses to identify the nonlinear complexity of the spatial distributions of elemental concentrations in the Er’renshan ore field.Initially,the raw concentrations were transformed into log-ratios following the principles of composition data theory to alleviate the impact of the closure effect.Multifractal analysis was then conducted to characterise the nonlinear complexity of the concentration distributions.Furthermore,principal component analysis(PCA)and factor analysis(FA)were applied to identify spurious correlations and the potential factors controlling the distribution patterns.The results demonstrate that:a)the raw data are biased,while the log-ratio data are unbiased and more reliable;b)the spatial distributions of elemental concentrations exhibit nonlinear complexity;and c)the elemental distribution in the study area is largely controlled by structural factors. 展开更多
关键词 nonlinear complexity compositional data FRACTAL multivariate statistical analysis element distribution
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Ecological Models Reveal a Weakened Population Structure, and Distribution Drivers of Osyris lanceolata (Santalaceae) in the Karamoja Sub-Region, Uganda
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作者 Ben Belden Mugula Samuel Kuria Kiboi +6 位作者 James Ireri Kanya Harald Meimberg Manuel Curto Paul Okullo Anthony Egeru Jenipher Biira Salamula Stephen F. Omondi 《Open Journal of Ecology》 2025年第2期153-173,共21页
Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and... Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives. 展开更多
关键词 Plant Ecology Hemiparasites Edaphic Drivers Ecological Modelling Multivariate Analysis Essential Oils “R”
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Association between metabolic parameters and erection in erectile dysfunction patients with hyperuricemia
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作者 Guo-Wei Du Pei-Ning Niu +6 位作者 Zhao-Xu Yang Xing-Hao Zhang Jin-Chen He Tao Liu Yan Xu Jian-Huai Chen Yun Chen 《Asian Journal of Andrology》 2025年第4期482-487,共6页
The relationship between hyperuricemia(HUA)and erectile dysfunction(ED)remains inadequately understood.Given that HUA is often associated with various metabolic disorders,this study aims to explore the multivariate li... The relationship between hyperuricemia(HUA)and erectile dysfunction(ED)remains inadequately understood.Given that HUA is often associated with various metabolic disorders,this study aims to explore the multivariate linear impacts of metabolic parameters on erectile function in ED patients with HUA.A cross-sectional analysis was conducted involving 514 ED patients with HUA in the Department of Andrology,Jiangsu Province Hospital of Chinese Medicine(Nanjing,China),aged 18 to 60 years.General demographic information,medical history,and laboratory results were collected to assess metabolic disturbances.Sexual function was evaluated using the 5-item version of the International Index of Erectile Function(IIEF-5)questionnaire.Based on univariate analysis,variables associated with IIEF-5 scores were identified,and the correlations between them were evaluated.The effects of these variables on IIEF-5 scores were further explored by multiple linear regression models.Fasting plasma glucose(β=−0.628,P<0.001),uric acid(β=−0.552,P<0.001),triglycerides(β=−0.088,P=0.047),low-density lipoprotein cholesterol(β=−0.164,P=0.027),glycated hemoglobin(HbA1c;β=−0.562,P=0.012),and smoking history(β=−0.074,P=0.037)exhibited significant negative impacts on erectile function.The coefficient of determination(R²)for the model was 0.239,and the adjusted R²was 0.230,indicating overall statistical significance(F-statistic=26.52,P<0.001).Metabolic parameters play a crucial role in the development of ED.Maintaining normal metabolic indices may aid in the prevention and improvement of erectile function in ED patients with HUA. 展开更多
关键词 erectile dysfunction HYPERURICEMIA IIEF-5 metabolic parameters multivariate linear regression
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Functional Connectivity Encodes Sound Locations by Lateralization Angles
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作者 Renjie Tong Shaoyi Su +3 位作者 Ying Liang Chunlin Li Liwei Sun Xu Zhang 《Neuroscience Bulletin》 2025年第2期261-271,共11页
The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment.Previous studies have suggested that there is an auditory“where”pathway in the cortex for proce... The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment.Previous studies have suggested that there is an auditory“where”pathway in the cortex for processing sound locations.The neural activation in regions along this pathway encodes sound locations by opponent hemifield coding,in which each unilateral region is activated by sounds coming from the contralateral hemifield.However,it is still unclear how these regions interact with each other to form a unified representation of the auditory space.In the present study,we investigated whether functional connectivity in the auditory“where”pathway encoded sound locations during passive listening.Participants underwent functional magnetic resonance imaging while passively listening to sounds from five distinct horizontal locations(−90°,−45°,0°,45°,90°).We were able to decode sound locations from the functional connectivity patterns of the“where”pathway.Furthermore,we found that such neural representation of sound locations was primarily based on the coding of sound lateralization angles to the frontal midline.In addition,whole-brain analysis indicated that functional connectivity between occipital regions and the primary auditory cortex also encoded sound locations by lateralization angles.Overall,our results reveal a lateralization-angle-based representation of sound locations encoded by functional connectivity patterns,which could add on the activation-based opponent hemifield coding to provide a more precise representation of the auditory space. 展开更多
关键词 Sound localization Functional connectivity Multivariate pattern analysis Lateralization angle
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Spatial distribution of landslides in response to the geomorphometric constraints in Darma Valley,Kumaun Himalaya
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作者 Mohd SHAWEZ Vikram GUPTA +1 位作者 Anand Kumar GUPTA Gautam RAWAT 《Journal of Mountain Science》 2025年第1期48-70,共23页
The Kumaun Himalaya is well-known as a geologically and tectonically complex region that amplifies mass wasting processes,particularly landslides.This study attempts to investigate the interplay between landslide dist... The Kumaun Himalaya is well-known as a geologically and tectonically complex region that amplifies mass wasting processes,particularly landslides.This study attempts to investigate the interplay between landslide distribution and the lithotectonic regime of Darma Valley,Kumaun Himalaya.A landslide inventory comprising 295 landslides in the area has been prepared and several morphotectonic proxies such as valley floor width to height ratio(Vf),stream length gradient index(SL),and hypsometric integral(HI)have been used to infer tectonic regime.Morphometric analysis,including basic,linear,aerial,and relief aspects,of 59 fourth-order sub-basins,has been carried out to estimate erosion potential in the study area.The result demonstrates that 46.77%of the landslides lie in very high,20.32%in high,21.29%in medium,and 11.61%in low erosion potential zones respectively.In order to determine the key parameters controlling erosion potential,two multivariate statistical methods namely Principal Component Analysis(PCA)and Agglomerative Hierarchical Clustering(AHC)were utilized.PCA reveals that the Higher Himalayan Zone(HHZ)has the highest erosion potential due to the presence of elongated sub-basins characterized by steep slopes and high relief.The clusters created through AHC exhibit positive PCA values,indicating a robust correlation between PCA and AHC.Furthermore,the landslide density map shows two major landslide hotspots.One of these hotspots lies in the vicinity of highly active Munsiyari Thrust(MT),while the other is in the Pandukeshwar formation within the MT's hanging wall,characterized by a high exhumation rate.High SL and low Vf values along these hotspots further corroborate that the occurrence of landslides in the study area is influenced by tectonic activity.This study,by identifying erosionprone areas and elucidating the implications of tectonic activity on landslide distribution,empowers policymakers and government agencies to develop strategies for hazard assessment and effective landslide risk mitigation,consequently safeguarding lives and communities. 展开更多
关键词 LANDSLIDES Geomorphometric analysis Multivariate statistical analysis Darma valley Kumaun Himalaya
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Nonlinear multilevel seemingly unrelated height-diameter and crown length mixed-effects models for the southern Transylvanian forests,Romania
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作者 Albert Ciceu Stefan Leca +1 位作者 Ovidiu Badea Lauri Mehtatalo 《Forest Ecosystems》 2025年第4期630-641,共12页
In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.In... In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.Instead of building univariate models for each response variable,we employed a multivariate approach using seemingly unrelated mixed-effects models.These models incorporated variables related to species mixture,tree and stand size,competition,and stand structure.With the inclusion of additional variables in the multivariate seemingly unrelated mixed-effects models,the accuracy of the height prediction models improved by over 10% for all species,whereas the improvement in the crown length models was considerably smaller.Our findings indicate that trees in mixed stands tend to have shorter heights but longer crowns than those in pure stands.We also observed that trees in homogeneous stand structures have shorter crown lengths than those in heterogeneous stands.By employing a multivariate mixed-effects modelling framework,we were able to perform cross-model random-effect predictions,leading to a significant increase in accuracy when both responses were used to calibrate the model.In contrast,the improvement in accuracy was marginal when only height was used for calibration.We demonstrate how multivariate mixed-effects models can be effectively used to develop multi-response allometric models that can be easily calibrated with a limited number of observations while simultaneously achieving better-aligned projections. 展开更多
关键词 Multivariate model Cross-model calibration Crown allometry Multilevel model Mixed stands Heterogeneous stand structure
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Exploration of influential factors about Qi-deficiency constitution of Traditional Chinese Medicine based on multi-methods
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作者 LUO Yue CHENG Xiaoen +4 位作者 JIANG Luxia SU Biliang ZHAO Yuxin OU Jintao WEN Chuanbiao 《Journal of Traditional Chinese Medicine》 2025年第3期693-701,共9页
OBJECTIVE:To find more influencing factors Qideficiency constitution of Traditional Chinese Medicine(TCM)using dynamic and comprehensive information.METHODS:Because grey relational analysis(GRA)is good at processing i... OBJECTIVE:To find more influencing factors Qideficiency constitution of Traditional Chinese Medicine(TCM)using dynamic and comprehensive information.METHODS:Because grey relational analysis(GRA)is good at processing incomplete information and has no special requirements for sample size and distribution.We acquired 2122 pieces of valid Qi-deficiency constitution dynamic data after preprocessing,and used GRA combing withχ~2 test and multivariate logistic regression analysis to discover and sort the influencing factors of Qideficiency constitution.RESULTS:For the calculation results of GRA,there were 10(62.5%)aspects whose grey correlation degrees were greater than 0.6.The results ofχ~2 test showed that all the above 10 aspects were statistically significant with Qideficiency constitution.The analysis results of multivariate logistic regression analysis showed the following factors were positively correlated with Qi-deficiency constitution:premature birth,sleeping late and getting up early,sleeping late and getting up late,irregular sleeping,sleeping 6.0-6.9 h per day,artificial feeding,female,age at 18-19,and father's age at 18-19 years old when a baby at birth.The following factors were negatively correlated with Qi-deficiency constitution:sleeping 8.0-8.9 h per day and≥9.0 h per day,and age at 30-39 and 40-49 years old.CONCLUSIONS:It is necessary to pay attention to these innate and acquired information of individuals which may lead to Qi-deficiency constitution.And our research also provides a novel methodological thinking for analyzing the influential factors of TCM constitution. 展开更多
关键词 Qi-deficiency constitution influencing factors grey relational analysis univariate analysis multivariate analysis
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Tumor Displacement Prediction and Augmented Reality Visualization in Brain Tumor Resection Surgery
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作者 WANG Jiayu WANG Shuyi +4 位作者 WEI Yongxu LIAO Chencong SHANG Hanbing WANG Xue KANG Ning 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期733-743,共11页
The purpose of this study is to establish a multivariate nonlinear regression mathematical model to predict the displacement of tumor during brain tumor resection surgery.And the study will be integrated with augmente... The purpose of this study is to establish a multivariate nonlinear regression mathematical model to predict the displacement of tumor during brain tumor resection surgery.And the study will be integrated with augmented reality technology to achieve three-dimensional visualization,thereby enhancing the complete resection rate of tumor and the success rate of surgery.Based on the preoperative MRI data of the patients,a 3D virtual model is reconstructed and 3D printed.A brain biomimetic model is created using gel injection molding.By considering cerebrospinal fluid loss and tumor cyst fluid loss as independent variables,the highest point displacement in the vertical bone window direction is determined as the dependent variable after positioning the patient for surgery.An orthogonal experiment is conducted on the biomimetic model to establish a predictive model,and this model is incorporated into the augmented reality navigation system.To validate the predictive model,five participants wore HoloLens2 devices,overlaying the patient’s 3D virtual model onto the physical head model.Subsequently,the spatial coordinates of the tumor’s highest point after displacement were measured on both the physical and virtual models(actual coordinates and predicted coordinates,respectively).The difference between these coordinates represents the model’s prediction error.The results indicate that the measured and predicted errors for the displacement of the tumor’s highest point on the X and Y axes range from−0.6787 mm to 0.2957 mm and−0.4314 mm to 0.2253 mm,respectively.The relative errors for each experimental group are within 10%,demonstrating a good fit of the model.This method of establishing a regression model represents a preliminary attempt to predict brain tumor displacement in specific situations.It also provides a new approach for surgeons.By combining augmented reality visualization,it addresses the need for predicting tumor displacement and precisely locating brain anatomical structures in a simple and cost-effective manner. 展开更多
关键词 brain tumor intraoperative displacement biomimetic model multivariate nonlinear regression model augmented reality prediction error
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Quantifying and categorizing development paths of poverty-elimination counties in China:Based on the perspective of population-land-industry
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作者 Qianxi Zhang Zhi Cao +1 位作者 Sixin Su Xuanchang Zhang 《Geography and Sustainability》 2025年第2期44-56,共13页
China has achieved the poverty reduction goal of the United Nations 2030 Agenda for Sustainable Development 10 years ahead of schedule,contributing significantly to global poverty reduction.Despite extended efforts in... China has achieved the poverty reduction goal of the United Nations 2030 Agenda for Sustainable Development 10 years ahead of schedule,contributing significantly to global poverty reduction.Despite extended efforts in poverty elimination,there is a lack of quantitative studies categorizing and comparing poverty-elimination counties(PECs)based on their processes.This study proposes an innovative framework for analyzing PECs’development paths from the perspective of population-land-industry(PLI).We quantify the PLI matching degree of PECs in China during the critical phase of the battle against poverty through a multivariate matching model,classify PECs via K-means clustering according to the consistency in PLI matching degree evolution,and summarize the typical development patterns of PECs.Results indicate that the PLI matching degree of PECs in China increased substantially from 2015 to 2020,particularly in eastern areas,while the western region,including the Qinghai-Xizang Plateau and southwestern Xinjiang,shows untapped potential for improvement.Five types of PECs are identified,with the majority(30.1%)showing sustained moderate PLI matching and a minority(9.6%)experiencing long-term PLI mismatch.Industry is the shortfall of various PECs,and effective strategies to facilitate all types of PECs include the development of emerging businesses and the expansion of secondary and tertiary industries.Additionally,enriching rural labor force and increasing farmland use efficiency are essential for optimal PLI matching and positive interaction,ultimately ensuring poverty elimination and sustainable development. 展开更多
关键词 Poverty elimination Multivariate matching model Spatial pattern Sustainable development patterns Sustainable Development Goals
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Multi-mode acceleration optimization control for adaptive cycle engine based on variable geometry components
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作者 Yifan WANG Haoying CHEN +1 位作者 Xuankai LIU Haibo ZHANG 《Chinese Journal of Aeronautics》 2025年第9期3-25,共23页
The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of... The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of thrust.Therefore,this paper proposes a multi-mode acceleration optimization control method that simultaneously performs ACE acceleration and mode transition.Firstly,an ACE component model with inlet flow characteristics was established,and the performance before and after mode transition were analyzed.Secondly,the principle of ACE acceleration optimization was analyzed,and the Front Variable Area Bypass Injector(FVABI)and Mode Selection Valve(MSV)were adopted in the acceleration process.Finally,based on the Sequential Quadratic Programming(SQP)algorithm,considering the degradation effects of engine components,we optimize the acceleration control plan for fuel and variable geometry mechanisms.The simulation results show that at the subsonic cruise point,the ACE multi-mode acceleration optimization control method can shorten the acceleration time from idle to middle state by 30.33%,and accelerate the thrust response speed by 33.72%.When the compressor flow rate of ACE deteriorates by 2% and the high-pressure turbine efficiency deteriorates by 4%,the adaptive acceleration control plan increases the high-pressure speed by 2.13% and thrust by about 6.82%;within the flight envelope,the acceleration time is reduced by more than 25%,and the thrust response speed is increased by more than 20%. 展开更多
关键词 Adaptive cycle engine Mode transition Multivariate acceleration plan Sequential quadratic planning Variable geometry components
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On the Zero Coprime Equivalence of Multivariate Polynomial Matrices
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作者 CHEN Zuo LI Dongmei GUO Xu 《Wuhan University Journal of Natural Sciences》 2025年第1期32-42,共11页
The zero coprime system equivalence is one of important research in the theory of multidimensional system equivalence,and is closely related to zero coprime equivalence of multivariate polynomial matrices.We first dis... The zero coprime system equivalence is one of important research in the theory of multidimensional system equivalence,and is closely related to zero coprime equivalence of multivariate polynomial matrices.We first discuss the relation between zero coprime equivalence and unimodular equivalence for polynomial matrices.Then,we investigate the zero coprime equivalence problem for several classes of polynomial matrices,some novel findings and criteria on reducing these matrices to their Smith normal forms are obtained.Finally,an example is provided to illustrate the main results. 展开更多
关键词 multidimensional system multivariate polynomial matrix zero coprime equivalence unimodular equivalence Smith normal form
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Sex‐Related Differences in Risk Factors Associated With Nonhealing or Recurrence of Hyperthyroidism in Patients With Graves'Disease Treated With Radioactive Iodine
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作者 Haolin Shen Yuegui Wang +3 位作者 Jianmei Liao Xianbo Zuo Bo Zhang Xiao Yang 《Health Care Science》 2025年第3期188-194,共7页
Background:To evaluate sex‐related differences in the risk factors associated with nonhealing or recurrence of hyper-thyroidism(NHRH)in patients with Graves'disease(GD)treated with radioactive iodine.Methods:In t... Background:To evaluate sex‐related differences in the risk factors associated with nonhealing or recurrence of hyper-thyroidism(NHRH)in patients with Graves'disease(GD)treated with radioactive iodine.Methods:In total,285 patients were enrolled.Data on radioactive iodine(RAI)dosage,ultrasound indexes of the thyroid,and other clinical factors were collected.Patients were divided into NHRH and non‐NHRH(hypothyroidism or euthyroidism)groups based on treatment outcomes.Univariate and multivariate weighted logistic regression analyses were used to identify factors associated with NHRH.Sex‐specific analyses of these risk factors were also conducted.Results:There were no significant differences between the two groups in terms of sex,thyroid shear wave elastography velocity values,or pretreatment serum free thyroxine(FT4)levels.Thyroid volume and age were independently associated with NHRH,with the odds of NHRH gradually decreasing as age increased.In subgroup analyses,both age and thyroid volume were independent risk factors for NHRH in female patients(p<0.05),while in male patients,only FT4 was independently associated with NHRH(p<0.05).Conclusions:In patients of different sexes,the influence of thyroid volume,age,and FT4 on treatment outcomes exhibits distinct patterns. 展开更多
关键词 nonhealing radioactive iodinemethods risk factors radioactive iodine rai dosageultrasound indexes RECURRENCE SEX clinical factors multivariate weighted logistic
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Ink-jetting-based conformal additive manufacturing:advantages,opportunities,and challenges
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作者 Hao Yi Xiaoqi Guo +3 位作者 Fangle Chang Huajun Cao Jia An Chee Kai Chua 《International Journal of Extreme Manufacturing》 2025年第3期49-79,共31页
Ink-jetting printing stands out among various conformal additive manufacturing techniques for its multi-material,digital control,and process flexibility.Ink-jetting-based conformal additive manufacturing is renowned f... Ink-jetting printing stands out among various conformal additive manufacturing techniques for its multi-material,digital control,and process flexibility.Ink-jetting-based conformal additive manufacturing is renowned for its adaptability to complex topological surfaces and is emerging as a critical technology for future comprehensive conformal printing systems.This review highlights the distinctiveness of four primary ink-jetting printing techniques in conformal additive manufacturing—piezoelectric jetting,thermal bubble jetting,aerosol jetting,and electrohydrodynamic jetting—and delves into how these attributes endow ink-jetting printing with unique advantages in conformal processes.Furthermore,leveraging these advantages,the review discusses potential applications in conformal electronics,energy devices,biology,and electromagnetics to bolster the ongoing development and application.Considering the current state of this technology,the review identifies critical challenges for future advancements,such as dynamic surface printing,integrated fabrication of multifunctional conformal structures,and the balance between resolution and throughput.This review summarizes the latest research and technological advancements in ink-jetting-based conformal additive manufacturing,aiding in its innovative applications and enhanced manufacturing capabilities in the future. 展开更多
关键词 conformal additive manufacturing ink-jetting printing multi-material deposition multivariate digital drive multidimensional process flexibility
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