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Thin-Layer Convective Solar Drying and Mathematical Modelling of the Drying Kinetics of Marrubium vulgare Leaves
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作者 Mohammed Benamara Boumediene Touati +1 位作者 Said Bennaceur Bendjillali Ridha Ilyas 《Energy Engineering》 2026年第1期393-416,共24页
This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,5... This study explores the thin-layer convective solar drying of Marrubium vulgare L.leaves under conditions typical of sun-rich semi-arid climates.Drying experiments were conducted at three inlet-air temperatures(40℃,50℃,60℃)and two air velocities(1.5 and 2.5 m·s^(-1))using an indirect solar dryer with auxiliary temperature control.Moisture-ratio data were fitted with eight widely used thin-layer models and evaluated using correlation coefficient(r),root-mean-square error(RMSE),and Akaike information criterion(AIC).A complementary heattransfer analysis based on Reynolds and Prandtl numbers with appropriate Nusselt correlations was used to relate flow regime to drying performance,and an energy balance quantified the relative contributions of solar and auxiliary heat.The logarithmic model consistently achieved the lowest RMSE/AIC with r>0.99 across all conditions.Higher temperature and air velocity significantly reduced drying time during the decreasing-rate period,with no constantrate stage observed.On average,solar input supplied the large majority of the thermal demand,while the auxiliary heater compensated short irradiance drops to maintain setpoints.These findings provide a reproducible dataset and a modelling benchmark for M.vulgare leaves,and they support energy-aware design of hybrid solar dryers formedicinal plants in sun-rich regions. 展开更多
关键词 Solar drying modelLING Marrubiun vulgare L drying kinetics drying characteristic curve
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Prediction model for quality of life in sepsis survivors one year after discharge
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作者 Yi Yao Wenjin Li +3 位作者 Dejiang Hong Ze Chen Kai Peng Guangju Zhao 《World Journal of Emergency Medicine》 2026年第2期105-112,共8页
BACKGROUND:Sepsis survivors experience poor long-term quality of life post-discharge.The aim of this study was to analyze the factors that impact the long-term quality of life of sepsis survivors and develop a clinica... BACKGROUND:Sepsis survivors experience poor long-term quality of life post-discharge.The aim of this study was to analyze the factors that impact the long-term quality of life of sepsis survivors and develop a clinical prediction model.METHODS:A total of 442 sepsis patients from the Emergency Intensive Care Unit of a tertiary hospital in Wenzhou were included.These patients were assigned to the training set or the validation set at a ratio of 7:3.The European Quality of Life 5 Dimensions 5 Level Version(EQ-5D-5L) questionnaire was used to evaluate the quality of life in sepsis survivors one year after discharge.Multivariate logistic regression analysis was used to identify predictors,which were then used to develop the prediction model and subsequently derive a scoring system.The model's effectiveness was assessed using an area under the receiver operating characteristic curve,calibration curves,and clinical decision analysis.RESULTS:Of the 442 patients included,70 died one year after discharge,and 372 completed the questionnaire.A total of 46.6% of sepsis survivors have poor quality of life one year after discharge in the training set.Multivariate logistic regression revealed that age,platelet,serum albumin,serum urea,and C-reactive protein were independent risk factors for poor quality of life in sepsis survivors.The area under the curve of the scoring system was 0.777(95% CI:0.726–0.828).The calibration curves showed that it was well calibrated.Decision curve analysis indicated that the scoring system provided good clinical usefulness.The internal validation also demonstrated its effectiveness.CONCLUSION:The prediction model incorporating five risk factors may predict quality of life one year after discharge in sepsis survivors,which provides a measure to develop post-discharge rehabilitation and follow-up plans for this patient population. 展开更多
关键词 SEPSIS Sepsis survivors Quality of life EQ-5D-5L Prediction model
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The Continuation Task and the Model-as-Feedback Writing Task in L2 Writing Development:Timing of Model Texts
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作者 Xiaoyan Zhang 《Chinese Journal of Applied Linguistics》 2026年第1期76-91,160,共17页
This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a con... This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a continuation group, a MAFW group, and a control group, each with30 learners. A pretest and a posttest were used to gauge L2 writing development. Results showedthat the continuation task outperformed the MAFW task not only in enhancing the overall qualityof L2 writing, but also in promoting the quality of three components of L2 writing, namely, content,organization, and language. The finding has important implications for L2 writing teaching andlearning. 展开更多
关键词 continuation task model-as-feedback writing task L2 writing development timing of model texts
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DNASE1L3 Mediates Hepatocellular Carcinoma Tumor Growth and Organoid Models via the Wnt/β-Catenin Signaling Pathway
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作者 Shulong Zhang Yijun Zhao +5 位作者 Li Geng Feihong Song Li Feng Jun Jiang Qianqian Cai Fei Fan 《Oncology Research》 2026年第3期691-724,共34页
Background:Hepatocellular carcinoma(HCC)is a highly lethal malignancy driven by both intrinsic oncogenic pathways and immune microenvironmental regulation.Emerging evidence suggests that DNASE1L3 may influence tumor b... Background:Hepatocellular carcinoma(HCC)is a highly lethal malignancy driven by both intrinsic oncogenic pathways and immune microenvironmental regulation.Emerging evidence suggests that DNASE1L3 may influence tumor biology and immune responses;however,its specific roles in HCC progression and macrophage-mediated regulation remain unclear.This study aimed to elucidate the biological functions of DNASE1L3 in HCC and to determine how it modulates tumor behavior and immune interactions.Methods:Bioinformatics analyses of the GSE41804 and Cancer Genome Atlas-Liver Hepatocellular Carcinoma(TCGA-LIHC)datasets were used to identify hub genes.Functional assays assessed the impact of DNASE1L3 on HCC cell proliferation,migration,invasion,and cell cycle progression.The effects of DNASE1L3 on macrophage polarization and the Wnt/β-catenin signaling pathway were examined using a co-culture system.An HCC organoid model was established to further validate its regulatory function.Results:Eight prognostic signature genes were identified,with deoxyribonuclease I-like 3(DNase I-like 3)selected as the hub gene.DNASE1L3 overexpression suppressed HCC cell growth,inhibited migration and invasion,induced G1 arrest,and modulated epithelial-mesenchymal transition(EMT)markers.DNASE1L3 knockdown promoted M2-like macrophage polarization.Mechanistically,DNASE1L3 interacted withβ-catenin to enhance its ubiquitination and degradation,thereby inhibiting Wnt/β-catenin signaling and reducing PD-L1 expression.DNASE1L3 overexpression similarly restricted organoid growth and suppressed pathway activity.Conclusion:DNASE1L3 acts as a negative regulator of HCC progression by targeting the Wnt/β-catenin pathway and reducing PD-L1 expression,thereby influencing both tumor cell behavior and macrophage-mediated immune responses. 展开更多
关键词 Hepatocellular carcinoma DNASE1L3 Wnt/β-catenin signaling pathway organoid models tumor growth
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A fractional-order improved FitzHugh–Nagumo neuron model 被引量:1
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作者 Pushpendra Kumar Vedat Suat Erturk 《Chinese Physics B》 2025年第1期519-528,共10页
We propose a fractional-order improved Fitz Hugh–Nagumo(FHN)neuron model in terms of a generalized Caputo fractional derivative.Following the existence of a unique solution for the proposed model,we derive the numeri... We propose a fractional-order improved Fitz Hugh–Nagumo(FHN)neuron model in terms of a generalized Caputo fractional derivative.Following the existence of a unique solution for the proposed model,we derive the numerical solution using a recently proposed L1 predictor–corrector method.The given method is based on the L1-type discretization algorithm and the spline interpolation scheme.We perform the error and stability analyses for the given method.We perform graphical simulations demonstrating that the proposed FHN neuron model generates rich electrical activities of periodic spiking patterns,chaotic patterns,and quasi-periodic patterns.The motivation behind proposing a fractional-order improved FHN neuron model is that such a system can provide a more nuanced description of the process with better understanding and simulation of the neuronal responses by incorporating memory effects and non-local dynamics,which are inherent to many biological systems. 展开更多
关键词 FitzHugh-Nagumo neuron model generalized Caputo fractional derivative L1 predictor-corrector method STABILITY error estimation
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Efficient implementation of the k-√k L turbulence model with the discontinuous Galerkin method
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作者 Zhenhua Jiang Chao Yan +1 位作者 Jian Yu Yao Li 《Acta Mechanica Sinica》 2025年第4期70-81,共12页
We present the approaches to implementing the k-√k L turbulence model within the framework of the high-order discontinuous Galerkin(DG)method.We use the DG discretization to solve the full Reynolds-averaged Navier-St... We present the approaches to implementing the k-√k L turbulence model within the framework of the high-order discontinuous Galerkin(DG)method.We use the DG discretization to solve the full Reynolds-averaged Navier-Stokes equations.In order to enhance the robustness of approaches,some effective techniques are designed.The HWENO(Hermite weighted essentially non-oscillatory)limiting strategy is adopted for stabilizing the turbulence model variable k.Modifications have been made to the model equation itself by using the auxiliary variable that is always positive.The 2nd-order derivatives of velocities required in computing the von Karman length scale are evaluated in a way to maintain the compactness of DG methods.Numerical results demonstrate that the approaches have achieved the desirable accuracy for both steady and unsteady turbulent simulations. 展开更多
关键词 Discontinuous Galerkin method k-√k L turbulence model High-order scheme
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“金葵子”L.P.K生物肥在豇豆上的应用效果研究
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作者 袁治国 罗志勇 +2 位作者 杨伟清 邱婵 孔冬华 《中文科技期刊数据库(全文版)农业科学》 2025年第4期143-146,共4页
本研究聚焦于金葵子 L.P.K 生物肥在豇豆种植领域的应用效能,通过严谨的田间试验设计,全面对比了该生物肥与传统常规施肥模式对豇豆生长全周期、最终产量以及内在品质的影响差异。研究结果确凿地表明,金葵子 L.P.K 生物肥的施用能够显... 本研究聚焦于金葵子 L.P.K 生物肥在豇豆种植领域的应用效能,通过严谨的田间试验设计,全面对比了该生物肥与传统常规施肥模式对豇豆生长全周期、最终产量以及内在品质的影响差异。研究结果确凿地表明,金葵子 L.P.K 生物肥的施用能够显著地促进豇豆植株的生长态势,有效地增加经济产量,并切实地提升产品品质。本研究成果为金葵子 L.P.K 生物肥在豇豆商业化生产中的广泛应用提供了坚实且科学的理论依据与实践支撑。 展开更多
关键词 金葵子 l.p.K 生物肥 豇豆 生长发育 产量 品质
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A Total Variational Image Denoising Model Coupled with a New Non-local Edge Extractor and a Level Set Curvature Gradient
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作者 Zhou Han Xianchun Zhou +1 位作者 Binxin Tang Siqi Lu 《Instrumentation》 2025年第2期47-59,共13页
To solve the problem of false edges in a flat region of l_(1)norm total variational TV model,an edge extractor based on non-local idea is proposed in this paper.The new edge extractor can effectively suppress the infl... To solve the problem of false edges in a flat region of l_(1)norm total variational TV model,an edge extractor based on non-local idea is proposed in this paper.The new edge extractor can effectively suppress the influence of noise and extract the edge information of the image.The new edge extractor is used as the adaptive function and the weighting function of the l_(p) norm variational model to control the noise reduction ability of the model,and a new model 1 is obtained.Considering that the new model 1 only uses the gradient mode as the image feature operator,which is insufficient to express the image texture information,a new level set curvature gradient variational model 2 combined with the edge extractor is proposed.The new model 2 uses the idea of minimum curvature of the level set of clear images to obtain noise reduction images.By coupling new model 1 and new model 2 to smooth the noise and protect more textures,a new Non-local level set denoising model(NLSDM)for image noise reduction is obtained.The experimental results show that compared with the noise reduction model,the new model has significantly improved the peak signal-to-noise ratio and structural similarity,and the effect of noise reduction and edge preservation is better. 展开更多
关键词 TV model the l_(p)norm NONLOCAL pfunction level set curvature term of regularization
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A data-driven identification method for reaction rate constant and diffusion coefficient in the P2D model
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作者 Gaoyang Li Xiaoyu Guo +8 位作者 Yongshuai Li Jialong Huang Zhirui Wang Yizheng Ma Litao Zhu Hui Pan Feng Shao Hao Ling Yulin Min 《Chinese Journal of Chemical Engineering》 2025年第12期188-197,共10页
To ensure the safe operation of batteries,accurately obtaining key internal state parameters is essential.However,traditional parameter measurement methods either require opening the battery or long-term measurements,... To ensure the safe operation of batteries,accurately obtaining key internal state parameters is essential.However,traditional parameter measurement methods either require opening the battery or long-term measurements,which are impractical.Therefore,the fixed values are commonly used for these parameters in electrochemical models and have significant limitations.To overcome these limitations,this paper proposes a deep neural network(DNN)based data-driven evaluation method to determine model parameters.By coupling an improved one-dimensional isothermal pseudo-twodimensional(P2D)model with DNN,this study identified concentration-dependent parameters through detailed discharge curve analysis.The results show that the data-driven method can effectively obtain the change trend of concentration-dependent parameters through the charge and discharge curve,and the method can be extended to different battery systems in different discharge rates and aging applications.This work is expected to provide new parameter selection insights for data-driven battery prediction and monitoring models. 展开更多
关键词 Internal state parameters of batteries P2D model Parameter identification Deep neural network(DNN) Data-driven evaluation method
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Stability analysis of distributed Kalman filtering algorithm for stochastic regression model
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作者 Siyu Xie Die Gan Zhixin Liu 《Control Theory and Technology》 2025年第2期161-175,共15页
The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysi... The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysis of the proposed distributed KF algorithm without independent and stationary signal assumptions,which implies that the theoretical results are able to be applied to stochastic feedback systems.Note that the main difficulty of stability analysis lies in analyzing the properties of the product of non-independent and non-stationary random matrices involved in the error equation.We employ analysis techniques such as stochastic Lyapunov function,stability theory of stochastic systems,and algebraic graph theory to deal with the above issue.The stochastic spatio-temporal cooperative information condition shows the cooperative property of multiple sensors that even though any local sensor cannot track the time-varying unknown signal,the distributed KF algorithm can be utilized to finish the filtering task in a cooperative way.At last,we illustrate the property of the proposed distributed KF algorithm by a simulation example. 展开更多
关键词 Distributed Kalman filtering algorithm Stochastic cooperative information condition Sensor networks (L_(p))-exponential stability Stochastic regression model
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基于地理信息系统的高速铁路大型临时设施选址模型
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作者 曾小清 邓波 +2 位作者 朱明昌 应沛然 李在奇 《同济大学学报(自然科学版)》 北大核心 2026年第1期98-106,共9页
大型临时设施选址对高速铁路施工建设起着至关重要的作用,其主要为建造高速铁路生产和提供预制梁。为针对性解决传统选址工作前期勘察综合成本大、选址结果主观倾向明显且难以量化评估等问题,系统地梳理了选址因素逻辑架构,构建了多层... 大型临时设施选址对高速铁路施工建设起着至关重要的作用,其主要为建造高速铁路生产和提供预制梁。为针对性解决传统选址工作前期勘察综合成本大、选址结果主观倾向明显且难以量化评估等问题,系统地梳理了选址因素逻辑架构,构建了多层次选址指标体系,结合ArcGIS空间解析,建立高速铁路大型临时设施选址模型。结合山东省已建成的大型临时设施实际位置进行模型验证,得到模型准确度为90%,佐证了本文选址模型的可行性与科学性。可为后续类似设施选址提供理论依据,也有助于形成高速铁路大型临时设施选址新的工作范式。 展开更多
关键词 高速铁路 大型临时设施 选址模型 地理信息系统(GIS)
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基于集成模型的地铁物流枢纽节点选址新方法研究
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作者 刘伟华 何洋 +1 位作者 张春雷 刘志雄 《物流技术》 2026年第1期31-45,共15页
地铁网络作为城市核心基础设施,凭借大运量、高准时性、低污染的显著优势,为物流模式创新提供了新路径。北京、深圳、天津等城市已启动地铁物流探索,依托现有地铁线路、站点及配套设施,在确保客运功能优先的基础上探索货物运输路径。然... 地铁网络作为城市核心基础设施,凭借大运量、高准时性、低污染的显著优势,为物流模式创新提供了新路径。北京、深圳、天津等城市已启动地铁物流探索,依托现有地铁线路、站点及配套设施,在确保客运功能优先的基础上探索货物运输路径。然而,地铁物流枢纽节点选址成为其规模化落地的核心阻碍,需突破多重复杂挑战。既要深度嵌入物流需求密集区域以缩短末端配送半径,又需与地铁线路、站点布局高效衔接,还需平衡成本类定量指标与服务质量、适配性等定性指标,决策难度远超传统物流选址。在这一复杂决策场景下,现有单一选址方法均表现出一定局限性,难以全面兼顾多元目标与约束条件。本文聚焦地铁物流枢纽节点选址问题,系统剖析集覆盖理论、P-中值法与层次分析法(AHP)的理论原理与应用逻辑,提出集成三种方法的综合选址新方法框架。通过集覆盖理论快速锁定初步范围,P-中值法筛选最优候选点组合,AHP量化评估优化,形成“理论解析—方法适配—流程整合—逻辑验证”的全流程方法论,为城市地铁物流枢纽规划提供可操作的技术路径。 展开更多
关键词 地铁物流 选址模型 集覆盖理论 P-中值法 层次分析法
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Bioinformatics Analysis and Homology Modeling Study of Protein Disulfide Isomerase(mPDI) from Medicago sativa L. 被引量:3
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作者 王海波 施晓东 +1 位作者 张梅芬 郭俊云 《Agricultural Science & Technology》 CAS 2009年第5期59-64,共6页
pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase( mPDI ), has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical p... pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase( mPDI ), has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical properties, hydrophilicity/hydrophobicity, signal peptide, secondary structure, coiled coil, transmembrane domains, O-glycogylation site, active site, subcellular localization, functional structural domains and three-dimensional structure were analyzed by a series of bioinformatics software. The results showed that mPDI was a hydrophobic and stable protein with 3 coiled coils, 30-glycogylation sites, 2 structural domains of thioredoxin, 2 active sites of thioredoxin, and located in rough endoplasmic reticulum. It has 512 amino acids, the theoretical pl is 4.98, and signal peptide located in 1-24AA. In the secondary structure, a-helix, random coil, extended chain is 26.37%, 53.32%, 20.31% respectively. The validation of modeling accords with the stereochemistry. 展开更多
关键词 Medicago sativa L. Protein disulfide isomerase Homology modeling
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H.E.L.P.系统治疗缺血性心脑血管疾病的临床研究 被引量:2
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作者 顾勇 薛骏 +4 位作者 董强 范虹 陆福明 林善锬 吕传真 《中国血液净化》 2002年第1期19-23,共5页
目的 回顾分析 H.E.L.P.系统(Heparin-induced extracorporeal LDL-Lp(a)-Fibrino-gen precipitation)在治疗缺血性心脑血管疾病中的疗效。方法 39例急性脑梗塞患者(治疗组 26例、对照组13例)、89例慢性脑梗塞患者、22例不稳定性心绞痛... 目的 回顾分析 H.E.L.P.系统(Heparin-induced extracorporeal LDL-Lp(a)-Fibrino-gen precipitation)在治疗缺血性心脑血管疾病中的疗效。方法 39例急性脑梗塞患者(治疗组 26例、对照组13例)、89例慢性脑梗塞患者、22例不稳定性心绞痛患者(治疗组12例、对照组10例)。分别检测上述患者H.E.L.P.治疗前、后的血脂、血粘度、纤维蛋白原水平,分别随访脑梗塞、不稳定性心绞痛患者治疗后3个月神经功能缺失(CSS)和日常生活活动量表(ADL)评分、心绞痛发作次数。结果 所有患者H.E.L.P.治疗后总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白(LDL)、纤维蛋白原(FIB)均下降了30~50%,血粘度指标下降了10~20%。急性脑梗塞患者治疗后3月CSS评分与对照组及治疗前均有显著差异(P<0.05),慢性脑梗塞患者治疗后2周较治疗前的CSS、ADL评分有明显改善(P<0.05)。不稳定性心绞痛患者H.E.L.P.治疗后3月的心绞痛发作次数较治疗前和对照组均明显减少(15.2±8.3次/月 vs 36.8± 12.5次/月,28.2± 10.9次/月 vs 20.2±11.6次/月,P<0.05)。结论H.E.L.P.系统选择性清除TC、TG、LDL、FIB、对高密度脂蛋白(HDL)影响不大。H.E.L.P.系统能有效、迅速、安全的改善血液流变学指标,对急性脑梗塞、不稳定性心绞痛有确切的疗效。 展开更多
关键词 H.E.l.p.系统 缺血性中风 不稳定性心绞痛
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预测地区公民旅游消费额的L.R—L.P模型 被引量:1
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作者 胡誉满 李勇红 《大学数学》 2003年第3期8-12,共5页
如何对地区公民旅游消费总额进行预测 ,是经济工作者及相关行业关注的问题 .本文用模糊系统分析的方法 ,建立一个地区的 L.R— L.P模型 ,利用模型的参数进行预测 ,提供一种辅助方法 .
关键词 旅游消费额 模糊系统分析 L.R-l.p模型 预测参数
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水力耦合下弱胶结砂岩力学特性及本构模型研究
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作者 李欣慰 姚直书 +2 位作者 陆路 黄献文 叶明 《地下空间与工程学报》 北大核心 2026年第1期60-71,共12页
水力耦合作用是造成围岩失稳和涌水灾害的重要因素。利用TAW-2000型岩石力学测试系统对白垩系弱胶结红砂岩进行水力耦合试验,分析了不同渗透水压和围压作用下红砂岩的非线性力学特性和强度特征,探索了渗透水压对红砂岩的劣化机理;结合... 水力耦合作用是造成围岩失稳和涌水灾害的重要因素。利用TAW-2000型岩石力学测试系统对白垩系弱胶结红砂岩进行水力耦合试验,分析了不同渗透水压和围压作用下红砂岩的非线性力学特性和强度特征,探索了渗透水压对红砂岩的劣化机理;结合有效应力原理、D-P强度准则和应变等价性理论,建立了反映水力耦合作用的损伤本构模型。结果表明:围压限制裂纹扩展,对力学性质起到强化作用,随着围压的增大,红砂岩的强度、弹性模量增大,泊松比降低;随着水压增大,红砂岩的强度、弹性模量降低,泊松比增大,表现出明显的软化效应;红砂岩黏土矿物含量少,胶结能力弱,在水压作用下颗粒间的胶结物溶解,丧失胶结强度,导致黏聚力大幅下降,丧失胶结强度是红砂岩软化的内在原因;本文建立的本构模型适用于常规三轴试验和水力耦合试验,能够较好地描述红砂岩的应力-应变关系和损伤演化规律;随着参数m增大,岩石塑性变形能力减弱,随着参数F_0的增加,岩石抵抗破坏和变形的能力增强。 展开更多
关键词 弱胶结砂岩 水力耦合 力学特性 D-P准则 本构模型
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三种失眠小鼠模型制备方法的比较与评价
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作者 李非凡 张怡博 +2 位作者 王静 朱金墙 郑文科 《中国组织工程研究》 北大核心 2026年第18期4685-4693,共9页
背景:稳定的动物失眠模型是研究失眠机制和抗失眠药物研发的重要工具。化学法结合物理方法构建失眠模型为动物失眠模型提供了良好的造模方法。目的:比较化学方法(对氯苯丙氨酸法)、物理方法(水环境睡眠剥夺法)和化学联合物理方法(对氯... 背景:稳定的动物失眠模型是研究失眠机制和抗失眠药物研发的重要工具。化学法结合物理方法构建失眠模型为动物失眠模型提供了良好的造模方法。目的:比较化学方法(对氯苯丙氨酸法)、物理方法(水环境睡眠剥夺法)和化学联合物理方法(对氯苯丙氨酸联合水环境睡眠剥夺法)构建小鼠失眠模型,探索最佳的造模方法。方法:将C57小鼠分别按照雄、雌性别随机分成空白组(不做处理)、对氯苯丙氨酸组、水平台组、对氯苯丙氨酸+水平台组,每组12只(雌、雄各半)。对氯苯丙氨酸组小鼠每天腹腔注射400 mg/kg对氯苯丙氨酸混悬液,连续3 d;水平台组小鼠连续3 d放入水环境睡眠剥夺平台中;对氯苯丙氨酸+水平台组小鼠放入睡眠剥夺平台中,且连续3 d腹腔注射400 mg/kg对氯苯丙氨酸混悬液。造模3 d后,对小鼠进行旷场实验、尼氏染色观察下丘脑及海马区神经元数量,酶联免疫吸附法检测血清中5-羟色胺、γ-氨基丁酸、多巴胺水平。结果与结论:①与空白组小鼠比较,3种模型组雄性小鼠的总路程、中心进入次数、平均速度和站立次数均呈上升趋势,其中对氯苯丙氨酸+水平台组变化最为明显(P<0.05或P<0.01);3种模型组雌性小鼠总路程、中心进入次数、平均速度和站立次数均呈上升趋势;②3种造模方法都可以减少小鼠下丘脑、海马区神经元数量,其中对氯苯丙氨酸+水平台组雌性小鼠神经元数量减少最为明显,神经元损伤最为严重;③与空白组相应性别小鼠比较,对氯苯丙氨酸+水平台组雌性小鼠血清3项指标变化更显著,5-羟色胺、γ-氨基丁酸显著降低(P<0.05),多巴胺水平显著升高(P<0.01)。结果说明:对氯苯丙氨酸联合水平台环境法建立的失眠模型对雌性小鼠相对更可靠、稳定,能为失眠研究提供较为理想的动物模型。 展开更多
关键词 失眠 动物模型 对氯苯丙氨酸 水环境睡眠剥夺 多巴胺 小鼠
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基于L系统的紫花苜蓿动态生长根系模型构建
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作者 杨贵侠 袁胜洋 +3 位作者 杨小玲 李思环 刘先峰 杨烜宇 《农业机械学报》 北大核心 2026年第1期319-328,共10页
针对现有紫花苜蓿根系动态生长模型和岩土工程生态防护方面的护坡植物根系模型空缺,将传统的L系统进行改进,提出了一种基于L系统的可应用于岩土工程生态防护领域的动态生长根系建模方法。通过控制伊犁黄土干密度、初始含水率和种植环境... 针对现有紫花苜蓿根系动态生长模型和岩土工程生态防护方面的护坡植物根系模型空缺,将传统的L系统进行改进,提出了一种基于L系统的可应用于岩土工程生态防护领域的动态生长根系建模方法。通过控制伊犁黄土干密度、初始含水率和种植环境的温湿度等,开展了紫花苜蓿种植,统计了不同生长时间下的紫花苜蓿的主根根长、主根直径、侧根数量、侧根直径、侧根长度和侧根分支点等。结合紫花苜蓿生长参数,基于L系统和建模技术,完成了紫花苜蓿动态生长根系模型的构建。结果表明:紫花苜蓿根系生长满足Logistic方程,侧根与主根夹角为15°~60°,侧根数量、分支间距和开始分支的长度等随着生长时间增加而增加,主根下段直径稳定在0.01~0.04 mm,靠近土壤表面的主根直径随时间变化较大;侧根直径小,直径变化也小。使用Logistic方程为紫花苜蓿根系生长模型,基于L系统结合建模技术构建了可用于数值仿真的紫花苜蓿动态生长根系模型,对该模型进行了验证,结果表明根系模型整体误差小。本文基于L系统的紫花苜蓿动态生长根系模型成功将紫花苜蓿根系的动态生长可视化,可应用于农业生产、植物学和岩土工程的数值仿真领域,为紫花苜蓿根系动态生长模型和岩土工程生态防护方面的植物动态生长根系模型建立提供参考。 展开更多
关键词 紫花苜蓿 动态生长模型 根系 L系统 岩土工程
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软土夹层地基上的互锁式L型沉箱稳定性试验研究
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作者 陈树理 郭伟 +1 位作者 任宇晓 陈伟 《岩土力学》 北大核心 2026年第1期49-60,共12页
互锁式L型沉箱作为一种新型沉箱结构,能够有效应对复杂海洋环境荷载。该结构在深水港码头、防波堤和人工岛等海洋基础设施中具有广阔的应用前景。通过室内加载模型试验,探究了所提出的互锁式L型沉箱(interlocking L-shaped caisson,简称... 互锁式L型沉箱作为一种新型沉箱结构,能够有效应对复杂海洋环境荷载。该结构在深水港码头、防波堤和人工岛等海洋基础设施中具有广阔的应用前景。通过室内加载模型试验,探究了所提出的互锁式L型沉箱(interlocking L-shaped caisson,简称ILC)替代传统L型沉箱(conventional L-shaped caisson,简称CLC)的可行性。研究了相邻ILC形成的六棱柱空腔内部的填充材料、地基类型和荷载形式对沉箱码头稳定性的影响。与CLC码头相比,在条形荷载下采用碎石或混凝土块联锁加固的ILC码头极限承载力分别提高了15.5%和20.1%。混凝土块联锁加固的ILC码头具有更优的承载性能。随着软土夹层地基替代砂土地基,ILC码头的极限承载力降低,其破坏模式由倾覆破坏变为整体失稳破坏,破坏面形态由直线-圆弧状变为多折线状。随着作用范围更小的集中荷载替代条形荷载,ILC码头的整体性变差,极限承载力显著降低,沉箱附近回填土表面沉降增大。 展开更多
关键词 海洋基础设施 互锁式L型沉箱 软土夹层地基 模型试验 稳定性
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基于L.P.模型的产品组合对开发价值影响研究
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作者 张镇森 陈萌 罗贞莉 《湖南理工学院学报(自然科学版)》 CAS 2009年第1期70-74,共5页
房地产项目前期产品研发对项目开发价值的实现具有重要意义.通过对市场调研数据的回归分析,得到各种房地产产品的建筑密度、容积率、销售速度、销售均价的期望值,建立L.P.模型,定量地研究不同产品组合对地块价值的影响.这种方法基于已... 房地产项目前期产品研发对项目开发价值的实现具有重要意义.通过对市场调研数据的回归分析,得到各种房地产产品的建筑密度、容积率、销售速度、销售均价的期望值,建立L.P.模型,定量地研究不同产品组合对地块价值的影响.这种方法基于已开发项目的客观数据,经过了市场的检验,有别于传统的对拟开发项目直接进行数据的假设,具有更高的科学性和合理性. 展开更多
关键词 l.p.模型 回归分析 产品组合:开发价值
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