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基于广义逆的桁架结构非线性homologous设计方法
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作者 占甫 关富玲 《科技通报》 2008年第4期510-515,共6页
运用M-P广义逆理论,研究了桁架结构的非线性homologous设计问题。将homologous变形约束条件引入结构基本方程,运用M-P广义逆矩阵的性质,将基本方程解的存在条件表示为含可变节点坐标变量的非线性方程组,通过求解该非线性方程组找到了满... 运用M-P广义逆理论,研究了桁架结构的非线性homologous设计问题。将homologous变形约束条件引入结构基本方程,运用M-P广义逆矩阵的性质,将基本方程解的存在条件表示为含可变节点坐标变量的非线性方程组,通过求解该非线性方程组找到了满足homologous变形约束要求的解,并为此推导了AA+(A为任意矩阵,A+为A的M-P广义逆矩阵)求偏导数的显式表达。最后的算例验证了本方法的正确性和有效性。 展开更多
关键词 homologous设计 非线性homologous变形约束条件 Moore-Penrose广义逆矩阵
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水力循环高架设施栽培装置优化设计及试验分析
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作者 朱庆松 严露露 +2 位作者 李玉斌 白东方 朱赞彬 《农机化研究》 北大核心 2025年第2期165-170,185,共7页
高架设施栽培模式提升了温室作物的产量和质量。为此,针对固定式高架设施遮荫问题,通过测定30°、40°、50°、60°等不同角度栽培装置的光照遮阴变化情况,确定了基于光照因素的最优高架栽培架式角度为50°。为了... 高架设施栽培模式提升了温室作物的产量和质量。为此,针对固定式高架设施遮荫问题,通过测定30°、40°、50°、60°等不同角度栽培装置的光照遮阴变化情况,确定了基于光照因素的最优高架栽培架式角度为50°。为了解决固定式高架设施角度过大、底层作物光照不足等问题,利用温室控温管路系统中水的压力,创新设计了一种以水轮机为动力的自动循环高架装置,分析了结构组成及工作原理,采用SolidWorks软件设计了三维模型。同时,通过Fluent模拟分析不同型号叶轮作用下的水力压力和速度变化,确定了双列直线型六叶轮为最优叶轮选型。装置是以水力产生动力使栽培槽围绕支架匀速转动,为高架设施架式设计提供一种新思路,在创造良好光照条件的同时减少能源的消耗,具有较高的经济效益,在实际生产中具有一定的推广应用价值。 展开更多
关键词 高架设施栽培装置 水力循环 优化设计
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Histological Assessment of Bone Regeneration in the Maxilla with Homologous Bone Graft:A Feasible Option for Maxillary Bone Reconstruction
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作者 Sergio Henrique Gonçalves Motta Ana Paula Ramos Soares +1 位作者 Juliana Campos Hasse Fernandes Gustavo Vicentis Oliveira Fernandes 《Journal of Renewable Materials》 EI CAS 2024年第1期131-148,共18页
Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilize... Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilized)graft and verify its reliability.Eight individuals were included from 2014 to 2018.The first surgery was performed to install homologous bone blocks in the maxilla.The period of the second intervention varied between 5 months and 15 days to 11 months(≈7.93 months).The biopsies were taken from the central region of the matured graft during the surgery for implant placement.All patients presented clinical and radiographic conditions for the installation of dental implants.There was a 100%of survival rate.The histological assessment showed that the homologous block bone graft was an osteoconductive biomaterial,with connective tissue present,and newly formed bone juxtaposed on its surface.There were bone trabeculae with osteocytes and active osteoblasts with connective tissue in the mineralization process;the remodeling process can be found through the reverse lines.A limited focus of necrosis with fibrosis was detected,with small resorption and areas of inflammatory infiltrate,but without clinical significance.The homologous block bone graft can be considered a feasible option to substitute the autogenous bone graft(gold standard),with predictable clinical and favorable histological results.The patients had a shorter surgical period,low morbidity,and an unlimited amount of biomaterial available at an accessible cost. 展开更多
关键词 Regeneration bone graft HISTOLOGY homologous allogenous AUTOGENOUS
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基于LabVIEW的拖拉机电气故障诊断系统设计
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作者 张扬 《农机化研究》 北大核心 2025年第2期239-243,248,共6页
设计了一种基于LabVIEW的拖拉机电气故障诊断系统,其采用模块化设计,可以自动检测和诊断拖拉机的电气故障,并提供可视化的诊断结果。系统由数据采集模块、信号处理模块、故障诊断模块和用户界面模块组成。数据采集模块负责采集拖拉机各... 设计了一种基于LabVIEW的拖拉机电气故障诊断系统,其采用模块化设计,可以自动检测和诊断拖拉机的电气故障,并提供可视化的诊断结果。系统由数据采集模块、信号处理模块、故障诊断模块和用户界面模块组成。数据采集模块负责采集拖拉机各个部件的电气参数数据,信号处理模块对采集到的数据进行处理和分析,故障诊断模块通过分析处理后的数据来判断拖拉机是否存在故障,并给出相应的诊断结果,用户界面模块提供友好的交互界面。试验结果表明:系统可以准确地诊断拖拉机的电气故障,具有良好的应用前景和推广价值。 展开更多
关键词 拖拉机 电气故障诊断 LABVIEW 数据采集 模块化设计
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Clinical and molecular significance of homologous recombination deficiency positive non-small cell lung cancer in Chinese population:An integrated genomic and transcriptional analysis
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作者 Yifei Wang Yidan Ma +14 位作者 Lei He Jun Du Xiaoguang Li Peng Jiao Xiaonan Wu Xiaomao Xu Wei Zhou Li Yang Jing Di Changbin Zhu Liming Xu Tianlin Sun Lin Li Dongge Liu Zheng Wang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第3期282-297,共16页
Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not ... Objective:The clinical significance of homologous recombination deficiency(HRD)in breast cancer,ovarian cancer,and prostate cancer has been established,but the value of HRD in non-small cell lung cancer(NSCLC)has not been fully investigated.This study aimed to systematically analyze the HRD status of untreated NSCLC and its relationship with patient prognosis to further guide clinical care.Methods:A total of 355 treatment-naïve NSCLC patients were retrospectively enrolled.HRD status was assessed using the AmoyDx Genomic Scar Score(GSS),with a score of≥50 considered HRD-positive.Genomic,transcriptomic,tumor microenvironmental characteristics and prognosis between HRD-positive and HRDnegative patients were analyzed.Results:Of the patients,25.1%(89/355)were HRD-positive.Compared to HRD-negative patients,HRDpositive patients had more somatic pathogenic homologous recombination repair(HRR)mutations,higher tumor mutation burden(TMB)(P<0.001),and fewer driver gene mutations(P<0.001).Furthermore,HRD-positive NSCLC had more amplifications in PI3K pathway and cell cycle genes,MET and MYC in epidermal growth factor receptor(EGFR)/anaplastic lymphoma kinase(ALK)mutant NSCLC,and more PIK3CA and AURKA in EGFR/ALK wild-type NSCLC.HRD-positive NSCLC displayed higher tumor proliferation and immunosuppression activity.HRD-negative NSCLC showed activated signatures of major histocompatibility complex(MHC)-II,interferon(IFN)-γand effector memory CD8+T cells.HRD-positive patients had a worse prognosis and shorter progressionfree survival(PFS)to targeted therapy(first-and third-generation EGFR-TKIs)(P=0.042).Additionally,HRDpositive,EGFR/ALK wild-type patients showed a numerically lower response to platinum-free immunotherapy regimens.Conclusions:Unique genomic and transcriptional characteristics were found in HRD-positive NSCLC.Poor prognosis and poor response to EGFR-TKIs and immunotherapy were observed in HRD-positive NSCLC.This study highlights potential actionable alterations in HRD-positive NSCLC,suggesting possible combinational therapeutic strategies for these patients. 展开更多
关键词 Non-small cell lung cancer homologous recombination deficiency genetic alterations transcriptional analysis tumor microenvironment PROGNOSIS
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Low testing rates and high BRCA prevalence: Poly (ADP-ribose) polymerase inhibitor use in Middle East BRCA/homologous recombination deficiency-positive cancer patients
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作者 Naveed Syed Ashish Vittalrao Chintakuntlawar +6 位作者 Deepti Vilasini Aisha Mohamed Al Salami Riad Al Hasan Imrana Afrooz Kanishka Uttam Chandani Ashok Uttam Chandani Aref Chehal 《World Journal of Clinical Oncology》 2024年第7期848-858,共11页
BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breas... BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer.They are also effective for new and recurrent ovarian cancers that are BRCA-or homologous recombination deficiency(HRD)-positive.However,data on these mutations and PARPi use in the Middle East are limited.AIM To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.METHODS This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations,and 25 of 65 ovarian cancer patients tested for HRD.These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023.Data were summarized using descriptive statistics and compared using counts and percentages.Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.RESULTS Among the 472 breast cancer patients,12.1%underwent BRCA testing,and 38.5%of 65 ovarian cancer patients received HRD testing.Pathogenic mutations were found in 25.6%of the tested patients:26.3%breast cancers had germline BRCA(gBRCA)mutations and 24.0%ovarian cancers showed HRD.Notably,40.0%of gBRCA-positive breast cancers and 66.0%of HRD-positive ovarian cancers were Middle Eastern and Asian patients,respectively.PARPi treatment was used in 5(33.3%)gBRCA-positive breast cancer patients as first-line therapy(n=1;7-months progression-free),for maintenance(n=2;>15-months progression-free),or at later stages due to compliance issues(n=2).Four patients(66.6%)with HRD-positive ovarian cancer received PARPi and all remained progression-free.CONCLUSION Lower testing rates but higher BRCA mutations in breast cancer were found.Ethnicity reflected United Arab Emirates demographics,with breast cancer in Middle Eastern and ovarian cancer in Asian patients. 展开更多
关键词 homologous recombination repair BRCA1 BRCA2 homologous recombination deficiency Ovarian cancer Breast cancer Poly(ADP-ribose)polymerase inhibitors OLAPARIB DNA double-strand breaks
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智能精密播种机的优化设计
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作者 吴政 《农机化研究》 北大核心 2025年第1期114-119,共6页
智能精密播种机是一种自动化的农业设备,可大幅提高种植效率、减少种植成本。但是,目前智能精密播种机依赖高精度的传感器、控制系统和算法来实现准确的种子投放和深度控制,需要较高的技术要求和技术支持,且对于一些不规则形状的种子或... 智能精密播种机是一种自动化的农业设备,可大幅提高种植效率、减少种植成本。但是,目前智能精密播种机依赖高精度的传感器、控制系统和算法来实现准确的种子投放和深度控制,需要较高的技术要求和技术支持,且对于一些不规则形状的种子或大粒小种的种子,适应性较差。为此,提出了一种智能精密播种机优化方案,并使用高精度传感器和控制系统实现多功能播种,控制种子的投放量和调整播种深度,使用节能设备模块化设计和使用易于更换的部件、数据分析功能和简单易用的用户界面。最后,通过田间试验进行功能性试验,结果表明:经过优化后的智能精密播种机播种变异系数≤5%,满足播种农艺要求,可以实现准确的种子投放和深度控制,避免种植密度不均匀和深度不一致等问题,从而提高种植效率和作物品质。 展开更多
关键词 智能精密播种机 优化设计 精度 多功能性 种植效率
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乡村低碳景观更新设计——以邛崃市直台村为例
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作者 李劲廷 付龙妃 《现代园艺》 2025年第1期160-162,共3页
随着乡村旅游的深入发展,大量对乡村景观的误读与建设性破坏现象愈演愈烈,显然违背了乡村景观原有的朴素生态规律,引发了乡村景观低碳化建设的思考。成都作为全国首批碳测综合试点城市,在进行乡村景观规划设计的过程中更应该重视低碳化... 随着乡村旅游的深入发展,大量对乡村景观的误读与建设性破坏现象愈演愈烈,显然违背了乡村景观原有的朴素生态规律,引发了乡村景观低碳化建设的思考。成都作为全国首批碳测综合试点城市,在进行乡村景观规划设计的过程中更应该重视低碳化建设。因此,基于现实背景需求,以邛崃市直台村为例,从生态田园景观、建筑材料、乡土植物景观营造、基础设施等方面提出了低碳景观设计策略,探讨乡村低碳景观更新设计的方法与实践。 展开更多
关键词 乡村景观 低碳策略 更新设计
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高校艺术设计专业课程思政融合教学路径的探索
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作者 杨梅 覃文勇 《现代园艺》 2025年第1期183-185,共3页
通过分析目前国内相关高校艺术设计专业课程思政教学模式的现状,全面剖析艺术设计专业课程思政教学实施所面临的困境,分析艺术设计专业学科特点以及美术艺术类学生的思想行为特点,探索提出将思政工作全面渗透到艺术设计专业日常课程教... 通过分析目前国内相关高校艺术设计专业课程思政教学模式的现状,全面剖析艺术设计专业课程思政教学实施所面临的困境,分析艺术设计专业学科特点以及美术艺术类学生的思想行为特点,探索提出将思政工作全面渗透到艺术设计专业日常课程教学中的相应对策,促进形成相对稳定的教学活动进程的结构形式及实施方法,以期为推进艺术设计专业课程思政建设提供一定新思路和参考。 展开更多
关键词 艺术设计 立德树人 课程思政 融合教学
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Establishing the homologous recombination score threshold in metastatic prostate cancer patients to predict the efficacy of PARP inhibitors
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作者 Diwei Zhao Anqi Wang +8 位作者 Yuanwei Li Xinyang Cai Junliang Zhao Tianyou Zhang Yi Zhao Yu Dong Fangjian Zhou Yonghong Li Jun Wang 《Journal of the National Cancer Center》 2024年第3期280-287,共8页
Background:The homologous recombination deficiency(HRD)score serves as a promising biomarker to iden-tify patients who are eligible for treatment with PARP inhibitors(PARPi).Previous studies have suggested a 3-biomark... Background:The homologous recombination deficiency(HRD)score serves as a promising biomarker to iden-tify patients who are eligible for treatment with PARP inhibitors(PARPi).Previous studies have suggested a 3-biomarker Genomic Instability Score(GIS)threshold of≥42 as a valid biomarker to predict response to PARPi in patients with ovarian cancer and breast cancer.However,the GIS threshold for prostate cancer(PCa)is still lacking.Here,we conducted an exploratory analysis to investigate an appropriate HRD score threshold and to evaluate its ability to predict response to PARPi in PCa patients.Methods:A total of 181 patients with metastatic castration-resistant PCa were included in this study.Tumor tissue specimens were collected for targeted next-generation sequencing for homologous recombination repair(HRR)genes and copy number variation(CNV)analysis.The HRD score was calculated based on over 50,000 single-nucleotide polymorphisms(SNP)distributed across the human genome,incorporating three SNP-based as-says:loss of heterozygosity,telomeric allelic imbalance,and large-scale state transition.The HRD score threshold was set at the last 5th percentile of the HRD scores in our cohort of known HRR-deficient tumors.The relation-ship between the HRD score and the efficacy in 16 patients of our cohort who received PARPi treatment were retrospectively analyzed.Results:Genomic testing was succeeded in 162 patients.In our cohort,61 patients(37.7%)had HRR mutations(HRRm).BRCA mutations occurred in 15 patients(9.3%).The median HRD score was 4(ranged from 0 to 57)in the total cohort,which is much lower than that in breast and ovarian cancers.Patients who harbored HRRm and BRCA or TP53 mutations had higher HRD scores.CNV occured more frequently in patients with HRRm.The last 5th percentile of HRD scores was 43 in the HRR-mutant cohort and consequently HRD high was defined as HRD scores≥43.In the 16 patients who received PARPi in our cohort,4 patients with a high HRD score achieved an objective response rate(ORR)of 100%while 12 patients with a low HRD score achieved an ORR of 8.3%.Progression-free survival(PFS)in HRD high patients was longer compared to HRD low patients,regardless of HRRm.Conclusions:A HRD score threshold of 43 was established and preliminarily validated to predict the efficacy of PARPi in this study.Future studies are needed to further verify this threshold. 展开更多
关键词 homologous recombination deficiency score THRESHOLD PARP inhibitors homologous recombination repair pathway MUTATION BRCA
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The Citron homology domain of MAP4Ks improves outcomes of traumatic brain injury
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作者 Xiaoling Zhong Wenjiao Tai +4 位作者 Meng-Lu Liu Shuaipeng Ma Tianjin Shen Yuhua Zou Chun-Li Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3233-3244,共12页
The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following insults.Whether targeting this pathway is beneficial to b... The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following insults.Whether targeting this pathway is beneficial to brain injury remains unclear.In this study,we showed that adeno-associated virus-delivery of the Citron homology domain of MAP4Ks effectively reduces traumatic brain injury-induced reactive gliosis,tauopathy,lesion size,and behavioral deficits.Pharmacological inhibition of MAP4Ks replicated the ameliorative effects observed with expression of the Citron homology domain.Mechanistically,the Citron homology domain acted as a dominant-negative mutant,impeding MAP4K-mediated phosphorylation of the dishevelled proteins and thereby controlling the Wnt/β-catenin pathway.These findings implicate a therapeutic potential of targeting MAP4Ks to alleviate the detrimental effects of traumatic brain injury. 展开更多
关键词 adeno-associated virus Citron homology Citron homology domain gene therapy mitogen-activated protein kinase kinase kinase kinases traumatic brain injury
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Sine oculis homeobox homolog family function in gastrointestinal cancer:Progression and comprehensive analysis
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作者 Yang-Zheng Lan Zheng Wu +3 位作者 Wen-Jia Chen Xin-Ning Yu Hua-Tao Wu Jing Liu 《World Journal of Clinical Oncology》 2025年第1期10-24,共15页
The sine oculis homeobox homolog(SIX)family,a group of transcription factors characterized by a conserved DNA-binding homology domain,plays a critical role in orchestrating embryonic development and organogenesis acro... The sine oculis homeobox homolog(SIX)family,a group of transcription factors characterized by a conserved DNA-binding homology domain,plays a critical role in orchestrating embryonic development and organogenesis across various organisms,including humans.Comprising six distinct members,from SIX1 to SIX6,each member contributes uniquely to the development and differentiation of diverse tissues and organs,underscoring the versatility of the SIX family.Dysregulation or mutations in SIX genes have been implicated in a spectrum of developmental disorders,as well as in tumor initiation and progression,highlighting their pivotal role in maintaining normal developmental trajectories and cellular functions.Efforts to target the transcriptional complex of the SIX gene family have emerged as a promising strategy to inhibit tumor development.While the development of inhibitors targeting this gene family is still in its early stages,the significant potential of such interventions holds promise for future therapeutic advances.Therefore,this review aimed to comprehensively explore the advancements in understanding the SIX family within gastrointestinal cancers,focusing on its critical role in normal organ development and its implications in gastrointestinal cancers,including gastric,pancreatic,colorectal cancer,and hepatocellular carcinomas.In conclusion,this review deepened the understanding of the functional roles of the SIX family and explored the potential of utilizing this gene family for the diagnosis,prognosis,and treatment of gastrointestinal cancers. 展开更多
关键词 Sine oculis homeobox homolog Gastrointestinal cancer Transcription factor Development Regulation Diagnosis THERAPEUTICS
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基于变密度法的SLM增材制造无人机承载接头结构拓扑优化设计
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作者 原帅超 王建峰 +2 位作者 段宇航 郝璐静 占小红 《工程科学学报》 EI 北大核心 2025年第1期56-65,共10页
针对某大型无人机机身轻量化需求,以选区激光熔化(Selective laser melting, SLM)制造的承载接头结构为研究对象建立有限元模型,基于ANSYS Workbench计算接头结构在不同极限工况下的强度、刚度性能,并根据材料最大许用应力准则进行校核... 针对某大型无人机机身轻量化需求,以选区激光熔化(Selective laser melting, SLM)制造的承载接头结构为研究对象建立有限元模型,基于ANSYS Workbench计算接头结构在不同极限工况下的强度、刚度性能,并根据材料最大许用应力准则进行校核.采用拓扑优化变密度法,以应力最小化为目标、保留质量40%为响应约束,对接头结构进行拓扑优化,根据优化结果设计两种重构方案并进行静力学验证.结果表明,两种模型重构方案分别减重了13.8%和13.3%,在轻量化程度相近的情况下,方案Ⅱ明显具有更小的应力分布以及变形程度,即最优重构方案成功实现轻量化设计,与原结构件相比质量减轻13.3%,且相较于其他方案承载能力最强,满足静态结构设计要求.为大型无人机承载接头结构实现低成本、轻量化的结构设计探索了新的途径. 展开更多
关键词 拓扑优化 静力学分析 增材制造 轻量化设计 结构设计
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论茶席插花设计存在的问题与对策
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作者 郑晓英 李新元 郑志勇 《现代园艺》 2025年第1期114-116,共3页
茶席插花在茶席设计中起着“画龙点睛”的作用。为探究茶席插花如何与茶席所体现的文化及整体氛围更加融合,分析茶席插花设计普遍存在的问题,提出了茶席插花设计的对策。通过选取合适的花材和插花方式,为茶席营造出和谐、雅致的环境,提... 茶席插花在茶席设计中起着“画龙点睛”的作用。为探究茶席插花如何与茶席所体现的文化及整体氛围更加融合,分析茶席插花设计普遍存在的问题,提出了茶席插花设计的对策。通过选取合适的花材和插花方式,为茶席营造出和谐、雅致的环境,提升整体视觉体验。 展开更多
关键词 茶席 茶席设计 茶席插花 插花艺术
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基于AHP-模糊综合评价法的遗址公园遗产活化设计需求研究
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作者 王博文 张跃伟 毕翼飞 《现代园艺》 2025年第1期43-45,共3页
随着社会各界对遗址公园关注度的持续提升,如何协调好遗址保护与展示利用之间的关系成为一个时代课题。诸多学者对于遗产活化设计在遗址公园中的应用展开了一些定性方面的探讨,而对其遗产活化设计需求的定量研究较为缺乏。本研究根据相... 随着社会各界对遗址公园关注度的持续提升,如何协调好遗址保护与展示利用之间的关系成为一个时代课题。诸多学者对于遗产活化设计在遗址公园中的应用展开了一些定性方面的探讨,而对其遗产活化设计需求的定量研究较为缺乏。本研究根据相关研究总结遗产活化设计方式,利用层次分析法和模糊综合评价法计算指标权重,并计算出各项指标的综合得分,针对评价结果,提出遗产活化设计的策略,探讨遗产活化设计针对遗址公园开发与建设的实施方案,为后续的遗址公园建设提供参考。 展开更多
关键词 遗址公园 遗产活化设计 层次分析法 模糊综合评价法
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非对称型假体设计及全膝关节置换后的力学分析
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作者 苏德君 董万鹏 +2 位作者 董跃福 张吉超 张震 《中国组织工程研究》 CAS 北大核心 2025年第3期510-516,共7页
背景:全膝关节置换是治疗膝关节晚期病症的有效手段,但假体衬垫容易因内部应力变化而产生磨损失效,寿命有限且术后患者的活动能力降低。如何对假体进行改进设计来满足患者更多的需求是假体研究的重要方向。目的:基于半月板的形态设计一... 背景:全膝关节置换是治疗膝关节晚期病症的有效手段,但假体衬垫容易因内部应力变化而产生磨损失效,寿命有限且术后患者的活动能力降低。如何对假体进行改进设计来满足患者更多的需求是假体研究的重要方向。目的:基于半月板的形态设计一种非对称型假体,并与对称设计的后稳定型假体进行比较,分析2种假体的应力分布情况和衬垫的接触面积变化,以探究非对称型假体设计是否存在优势。方法:通过有限元方法对1例膝骨关节炎患者进行模拟截骨和假体装配,建立基于非对称型假体及对称设计的后稳定型假体的全膝关节置换术后膝关节模型。在0°,10°,20°,30°的屈膝条件下,探究股骨假体、胫骨假体以及衬垫上的Mises应力,并通过对比衬垫内外侧的接触面积,分析全膝关节置换后膝关节生物力学变化和运动行为的改变。结果与结论:(1)在0°-30°的屈膝过程中,2种假体衬垫上的Mises应力峰值均表现出先减小后增大的趋势,且内侧始终大于外侧。(2)非对称型设计的假体与后稳定型假体相比,应力峰值更低;在屈膝30°时,非对称型假体衬垫内外侧的Mises应力峰值分别为15.81 MPa和11.95 MPa,后稳定型衬垫为16.70 MPa和13.76 MPa,两者内侧差值约为5.33%,而外侧则相差13.15%;对比股骨假体和胫骨假体上的Mises应力峰值,非对称型假体在屈膝过程中始终低于后稳定型假体。(3)在0°站立位时,后稳定型假体衬垫的内侧接触面积为17.96 mm^(2)、外侧为34.10 mm^(2);而非对称型假体衬垫的内外侧接触面积分别为105.47 mm^(2)和107.80 mm^(2),具有更大的接触面积且两侧差距更小。(4)结果表明,非对称型假体的生物力学表现更好,且能够对维持膝关节稳定性、提升关节活动度有所帮助。这种设计能够在一定程度上还原膝关节以内侧髁为轴进行外旋的运动机制,是一种更为有效的膝关节假体选择方案。 展开更多
关键词 膝关节 全膝关节置换 非对称型假体设计 生物力学 有限元分析
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基于分时共享的生活街区慢行空间设计——以武汉粮道街为例
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作者 李慧蓝 季岚 《现代园艺》 2025年第1期153-156,159,共5页
随着我国城市化加速,生活街区面临交通拥堵和空间利用不足等问题。随着我国城市化加速,生活街区路网无法承载不断增加的机动车流。以粮道街为例,交通拥堵、空间利用不足等问题亟待解决。通过分时共享理论,深入分析慢行系统的出行状况和... 随着我国城市化加速,生活街区面临交通拥堵和空间利用不足等问题。随着我国城市化加速,生活街区路网无法承载不断增加的机动车流。以粮道街为例,交通拥堵、空间利用不足等问题亟待解决。通过分时共享理论,深入分析慢行系统的出行状况和环境,重点探讨分时共享街区空间方法对生活街区慢行空间的积极作用。通过研究交通系统、空间功能、环境品质,提出系统化的“以人为本,让权于人”的发展方法,构建城市慢行空间,以此实现城市生活街区慢行空间的品质提升,为实现慢行、可持续为目标的人居环境建设提供思路与方法。 展开更多
关键词 老旧生活街区 慢行系统 分时共享 街区设计 保护更新
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骨组织工程中传统与仿生支架结构设计的差异
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作者 赵越 许燕 +4 位作者 周建平 张旭婧 陈宇彤 靳正阳 印治涛 《中国组织工程研究》 CAS 北大核心 2025年第16期3458-3468,共11页
背景:多孔支架作为新骨生长的临时基质在骨修复过程中起着关键作用,其中多孔支架的结构设计是骨修复过程中的研究重点。目的:综述传统支架(规则、均匀的支架)和仿生支架(不规则、不均匀的支架)在骨组织工程研究领域的应用。方法:检索中... 背景:多孔支架作为新骨生长的临时基质在骨修复过程中起着关键作用,其中多孔支架的结构设计是骨修复过程中的研究重点。目的:综述传统支架(规则、均匀的支架)和仿生支架(不规则、不均匀的支架)在骨组织工程研究领域的应用。方法:检索中国知网(CNKI)、维普、万方、Web of Science、Science Direct、PubMed、EI等数据库,选取2008年1月至2024年3月发表的文献,中文检索词为“骨组织工程,仿生支架,骨小梁,传统支架,骨修复,三周期极小曲面”,英文检索词为“bone tissue engineering,bionic scaffolds,bone trabeculae,traditional scaffolds,bone repair,TPMS”。最终纳入81篇文献进行综述。结果与结论:骨支架的结构设计是实现骨修复和骨再生的关键,骨组织工程中的支架技术已取得显著进展。传统的规则多孔支架因简单的制造流程和良好的机械性能被广泛应用,然而这类支架往往缺乏生物活性,难以模拟自然骨组织的复杂微环境,限制了其在促进细胞增殖和骨再生方面的能力。相反,仿生支架通过模拟自然骨组织的结构特征,提供了更适宜的生理微环境,促进了成骨细胞的增殖、分化及新骨的形成,为骨缺损有效治疗提供了新的思路。尽管仿生支架在理论上具有巨大的潜力,但在实际应用中仍面临诸多挑战,支架的生物相容性、生物活性及长期稳定性等因素仍需通过临床试验进行进一步验证。 展开更多
关键词 骨组织工程 仿生支架 骨小梁 传统支架 骨修复 三周期极小曲面 拓扑优化 结构设计 单胞阵列
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Effects of Different Concentrations of Homologous Probiotics on Small Intestinal Mucosa Structure of 42-day-old Broilers 被引量:1
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作者 张玉仙 王文利 +2 位作者 陈耀星 王子旭 曹静 《Agricultural Science & Technology》 CAS 2015年第12期2782-2785,共4页
In the study, the methods of applied histology and histochemistry were used to determine intestinal villus length, crypt depth, the ratio of intestinal villus length to crypt depth, mucous membrane thickness and intes... In the study, the methods of applied histology and histochemistry were used to determine intestinal villus length, crypt depth, the ratio of intestinal villus length to crypt depth, mucous membrane thickness and intestinal wall thickness of duodenum, jejunum and ileum of 42-day-old broilers, so as to study the effects of different conncentrations of homologous probiottcs on small intestinal mucosa struc- ture of the broilers. The results showed that the effect of 0.3% probiotics on small intestine mucosal structures was the best, such as the length of intestinal villus was the longest, the ratio of villus length to crypt depth was the largest, the thins of mucous membrane and intestinal wall was the thickest. These showed that 0,3% probiotics had best effect on improving and enhancing the digestion-absorption func- tion of the small intestine of the broilers. 展开更多
关键词 homologous probiotics Small intestine Mucosal structure
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具有非线性homologous变形约束的桁架结构形态分析 被引量:1
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作者 占甫 关富玲 《计算力学学报》 EI CAS CSCD 北大核心 2007年第5期648-653,共6页
研究了具有非线性homologous变形约束条件的桁架结构形态分析问题。在已有的线性homologous变形约束桁架形态分析的基础上,将结构的节点分成三类:homologous变形约束节点,形状可变节点和边界点。运用Moore-Penrose广义逆矩阵性质,将基... 研究了具有非线性homologous变形约束条件的桁架结构形态分析问题。在已有的线性homologous变形约束桁架形态分析的基础上,将结构的节点分成三类:homologous变形约束节点,形状可变节点和边界点。运用Moore-Penrose广义逆矩阵性质,将基础方程组解的存在条件表示为包含形状可变节点未知坐标的非线性方程组,为采用Newton-Raphson方法求解非线性方程组,对AA+(A为任意矩阵,A+为A的Moore-Penrose广义逆矩阵)求偏导数,找到了满足保型要求的形态,给出的桁架算例说明了本文方法的有效性。 展开更多
关键词 非线性homologous变形约束 广义逆矩阵 形态分析
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