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On the Existence of (v,3×3,λ)-Splitting Balanced Incomplete Block Design with λ between 2 to 9 认领 引用
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作者 苏仁旺 王金华 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第4期482-486,共5页
Let （v, u × c,λ）-splitting BIBD denote a （v, u × c,λ）-splitting balanced incomplete block design of order v with block size u × c and index A. The necessary conditions for the existence of a （v, ... Let （v, u × c,λ）-splitting BIBD denote a （v, u × c,λ）-splitting balanced incomplete block design of order v with block size u × c and index A. The necessary conditions for the existence of a （v, u × c,λ）-splitting BIBD are v ≥ uc, λ（v- 1） -- 0 0 mod （c（u- 1）） and Av（v- 1） - 0 mod （c^2u（u- 1））. In this paper, for 2 ≤λ≤ 9 the necessary conditions for the existence of a （v, 3 × 3, λ）-splitting BIBD are also sufficient with one possible exception for （v, λ） = （39, 9）. 展开更多
关键词 Splitting balanced incomplete block design group-divisible design （GDD）
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CONSTRUCTION OF NONSYSTEMATIC LOW-DENSITY PARITY-CHECK CODES BASED ON SYMMETRIC BALANCED INCOMPLETE BLOCK DESIGN 认领 引用
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作者 Lin Dengsheng Li Qiang Li Shaoqian 《Journal of Electronics(China)》 2008年第4期445-449,共5页
This paper studies the nonsystematic Low-Density Parity-Check(LDPC)codes based onSymmetric Balanced Incomplete Block Design(SBIBD).First,it is concluded that the performancedegradation of nonsystematic linear block co... This paper studies the nonsystematic Low-Density Parity-Check(LDPC)codes based onSymmetric Balanced Incomplete Block Design(SBIBD).First,it is concluded that the performancedegradation of nonsystematic linear block codes is bounded by the average row weight of generalizedinverses of their generator matrices and code rate.Then a class of nonsystematic LDPC codes con-structed based on SBIBD is presented.Their characteristics include:both generator matrices andparity-check matrices are sparse and cyclic,which are simple to encode and decode;and almost arbi-trary rate codes can be easily constructed,so they are rate-compatible codes.Because there aresparse generalized inverses of generator matrices,the performance of the proposed codes is only0.15dB away from that of the traditional systematic LDPC codes. 展开更多
关键词 Low-Density Parity-Check （LDPC） codes Nonsystematic codes Symmetric Balanced Incomplete Block Design （SBIBD） Finite projective geometries
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Splitting Balanced Incomplete Block Designs with Block Size 2×k 认领 引用
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作者 沈军 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第1期103-106,共4页
This paper investigated the existence of splitting balanced incomplete block designs with blck size 2× k .The necessary conditions for such a design are λ(v-1) ≡0(mod k ),and λv(v- 1)≡0(mod 2 k 2).It will sho... This paper investigated the existence of splitting balanced incomplete block designs with blck size 2× k .The necessary conditions for such a design are λ(v-1) ≡0(mod k ),and λv(v- 1)≡0(mod 2 k 2).It will show that the above necessary conditions are also sufficient for k =3 with the definite exception( v,λ )=(10,1) and with several possible exceptions. 展开更多
关键词 balanced incomplete block designs(BIBD) splitting BIBD
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Some Properties of Weak Block Designs 认领 引用
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作者 刘秀峰 张爱丽 朱洪 《Journal of Southwest Jiaotong University(English Edition)》 2002年第2期144-151,共8页
The necessary conditions for the existence of weak designs are given in the form of two inequalities in this paper. The relations among weak block designs (WBDs) , Balanced incomplete block designs ( BIBDs) and differ... The necessary conditions for the existence of weak designs are given in the form of two inequalities in this paper. The relations among weak block designs (WBDs) , Balanced incomplete block designs ( BIBDs) and differential balanced block designs (DBBDs) are researched. 展开更多
关键词 block design balance incomplete differential
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Optimal orthogonal block designs for three-component symmetric general blending models in mixture experiment 认领 引用
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作者 Jiawei Bao Yu Tang 《Statistical Theory and Related Fields》 CSCD 2026年第1期117-134,共18页
In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of ... In mixture experiments,the observed response is determined by the relative proportions of the components,consequently rendering the experimental region a simplex.This paper focuses primarily on the optimal designs of mixture experiments that involve process variables.Prior research has extensively delved into optimal orthogonal block designs for some classic mixture models with process variables.Based on the framework of general blending models,this paper proposes a class of symmetric linear mixture models,which can be regarded as a generalization of many existing ones.Under the orthogonal blocking conditions,orthogonal block designs are devised through Latin squares in the presence of process variables.TheD-,A-,and E-optimality criteria are utilized to obtain optimal designs at the boundary of the simplex in the case of 3 components.As the values of the exponents change,numerically derived optimal design points are presented to illustrate the pattern of their variations,and to verify the consistency of the results with previous research on some specific symmetric general blending models. 展开更多
关键词 Mixture experiments general blending models optimal designs orthogonal Latin squares block designs
Variable Selection in Randomized Block Design Experiment 认领 引用 被引量：1
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作者 Sadiah Mohammed Aljeddani 《American Journal of Computational Mathematics》 2022年第2期216-231,共16页
In the experimental field, researchers need very often to select the best subset model as well as reach the best model estimation simultaneously. Selecting the best subset of variables will improve the prediction accu... In the experimental field, researchers need very often to select the best subset model as well as reach the best model estimation simultaneously. Selecting the best subset of variables will improve the prediction accuracy as noninformative variables will be removed. Having a model with high prediction accuracy allows the researchers to use the model for future forecasting. In this paper, we investigate the differences between various variable selection methods. The aim is to compare the analysis of the frequentist methodology (the backward elimination), penalised shrinkage method (the Adaptive LASSO) and the Least Angle Regression (LARS) for selecting the active variables for data produced by the blocked design experiment. The result of the comparative study supports the utilization of the LARS method for statistical analysis of data from blocked experiments. 展开更多
关键词 Variable Selection Shrinkage Methods Linear Mixed Model Blocked Designs
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Some results on resolvable incomplete block designs 认领 引用 被引量：3
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作者 LIU Minqian FANG Kaitai 《Science China Mathematics》 2005年第4期503-512,共10页
This paper is concerned with the uniformity of a certain kind of resolvable incomplete block(RIB for simplicity)design which is called the PRIB design here.A sufficient and necessary condition is obtained,under which ... This paper is concerned with the uniformity of a certain kind of resolvable incomplete block(RIB for simplicity)design which is called the PRIB design here.A sufficient and necessary condition is obtained,under which a PRIB design is the most uniform in the sense of a discrete discrepancy measure,and the uniform PRIB design is shown to be connected.A construction method for such designs via a kind of U-type designs is proposed,and an existence result of these designs is given.This method sets up an important bridge between PRIB designs and U-type designs. 展开更多
关键词 block design discrepancy orthogonal array supersaturated design U-type design
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ORTHOGONAL GEOMETRIES OVER FINITE FIELDS WITH CHARACTERISTIC≠2 AND BLOCK DESIGNS 认领 引用 被引量：1
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作者 阳本傅 魏万迪 《Acta Mathematicae Applicatae Sinica》 1993年第3期269-280,共12页
By taking as blocks certain subspace-pairs of an orthogonal geometry over a finite field with characteristic≠2 we construct some new types of BIB designs and PBIB designs whose parameters are also given.
关键词 ORTHOGONAL GEOMETRIES OVER FINITE FIELDS WITH CHARACTERISTIC AND BLOCK DESIGNS BIB
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CONSTRUCTION OF OPTIMAL BLOCKING SCHEMES FOR ROBUST PARAMETER DESIGNS 认领 引用 被引量：2
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作者 杨建峰 张润楚 刘民千 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1431-1438,共8页
Robust parameter design （RPD） is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the c... Robust parameter design （RPD） is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the correspondence relation between fractional factorial RPDs and the blocking schemes for full factorial RPDs. In addition, we provide a construction of optimal blocking schemes that make all main effects and control-by-noise two-factor interactions estimable. 展开更多
关键词 Alias blocking factorial design factorial effect robust parameter design
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EMBEDDINGS OF SIMPLE TWO-FOLD BALANCED INCOMPLETE BLOCK DESIGNS WITH BLOCK SIZE FOUR 认领 引用
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作者 WANG JINHUA SHEN HAO 《Chinese Annals of Mathematics,Series B》 SCIE 2005年第4期643-650,共8页
The necessary and sufficient conditions for the existence of simple incomplete block design （v, ω; 4, 2）-IPBDs are determined. As a consequence, the necessary and sufficient conditions for the embeddings of simple ... The necessary and sufficient conditions for the existence of simple incomplete block design （v, ω; 4, 2）-IPBDs are determined. As a consequence, the necessary and sufficient conditions for the embeddings of simple two-fold balanced incomplete block designs with block size 4 are also determined. 展开更多
关键词 Block design Simple Embedding
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OPTIMIZATION DESIGN OF HYDRAULIC MANIFOLD BLOCKS BASED ON HUMAN-COMPUTER COOPERATIVE GENETIC ALGORITHM 认领 引用 被引量：10
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作者 Feng YiLi LiTian ShujunSchool of Mechanical Engineering,Dalian University of Technology,Dalian 116024, China 《Chinese Journal of Mechanical Engineering》 EI CAS 2003年第3期317-320,共4页
Optimization design of hydraulic manifold blocks (HMB) is studied as acomplex solid spatial layout problem. Based on comprehensive research into structure features anddesign rules of HMB, an optimal mathematical model... Optimization design of hydraulic manifold blocks (HMB) is studied as acomplex solid spatial layout problem. Based on comprehensive research into structure features anddesign rules of HMB, an optimal mathematical model for this problem is presented. Usinghuman-computer cooperative genetic algorithm (GA) and its hybrid optitation strategies, integratedlayout and connection design schemes of HMB can be automatically optimized. An example is given totestify it. 展开更多
关键词 Hydraulic manifold blocks (HMB) Human-computer cooperation Geneticalgorithm Optimization design
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General Solution of Normal Equations in the Intra-Block Analysis of PBIB Designs with Four Associates 认领 引用
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作者 Dav inder Kumar Garg Ghansham Mishra 《Journal of Mathematics and System Science》 2013年第8期412-416,共5页
General solution of normal equations in the general intra-block analysis of partially balanced incomplete block designs involving four associates is presented in this talk as they are quite useful in practice. Only in... General solution of normal equations in the general intra-block analysis of partially balanced incomplete block designs involving four associates is presented in this talk as they are quite useful in practice. Only intra-block estimates are given as the necessary formulae for inter-block estimates can be derived from them by changing the parameters as discussed in Rao[5]. We have obtained the general formulae for computation of four types of efficiencies, the average efficiency factor and the variance of the estimated elementary treatment contrast of the four types of comparisons irrespective of the type of association scheme a PBIB Design follows. 展开更多
关键词 Partially balanced incomplete block designs inter- block analysis intra-block analysis.
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Some Construction Methods of Optimum Chemical Balance Weighing Designs III 认领 引用
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作者 Rashmi Awad Shakti Banerjee 《Open Journal of Statistics》 2016年第1期37-48,共12页
Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs ... Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs are also obtained. 展开更多
关键词 Balanced Incomplete Block Design Symmetric Balanced Incomplete Block Design Ternary Balanced Block Design Variance Balanced Design Efficiency Balanced Design Nested Balanced Incomplete Block Design Weighing Design Chemical Balance Weighing Design Optimum Chemical Balance Weighing Design
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Block-Transitive 4-(v,k,4) Designs and Ree Groups 认领 引用
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作者 Shaojun Dai Ruihai Zhang 《Advances in Pure Mathematics》 2016年第5期317-320,共4页
This article is a contribution to the study of the automorphism groups of  designs. Let be a non-trivial  design where for some positive integer , and  is block-transitive. If the socle of G is iso... This article is a contribution to the study of the automorphism groups of  designs. Let be a non-trivial  design where for some positive integer , and  is block-transitive. If the socle of G is isomorphic to the simple groups of lie type, then G is not flag-transitive. 展开更多
关键词 Flag-Transitive Block-Transitive t-Design Ree Group
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Comparative Analysis on Space Form of Block in Arid Region and Ecological Design Strategy 认领 引用
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作者 Wang Yining Zang Xinyu Chen Tian 《Meteorological and Environmental Research》 2018年第3期24-29,共6页
Due to unique geographical position and climatic characteristics,there are more economic,social,resource,environmental and other problems in urban construction of arid region. Old urban block of Kashgar and typical bl... Due to unique geographical position and climatic characteristics,there are more economic,social,resource,environmental and other problems in urban construction of arid region. Old urban block of Kashgar and typical block of Masdar ecological city of Abu Dhabi are taken as the research objects. Based on summarizing the characteristics of traditional block and newly built ecological block in arid region,comparative analysis on their space forms and environmental designs is conducted,and the association mechanism between ecological adaptability and space form is generalized. From the aspects of block layout,block space,open space and architectural form,ecological design strategy of the block in arid region is proposed,which could provide the reference for development and construction of ecological city in arid region of China. 展开更多
关键词 Arid region Aho block Masdar ecological city Block Ecological design
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随机对照试验中随机分配常见问题对随机性与分组均衡性的影响 认领 引用
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作者 主雪鹭 晋菲斐 +1 位作者 姚晨 阎小妍 《中国食品药品监管》 CAS 2026年第7期54-67,共14页
目的:探讨临床试验中3类常见随机化情境对分组随机性与均衡性的影响,包括分层随机中误选分层因素所导致的操作偏差、多中心试验中存在中心样本量不足问题下的竞争分层设计挑战,以及动态随机化方法中最小化概率设置的参数选择问题。通过... 目的:探讨临床试验中3类常见随机化情境对分组随机性与均衡性的影响,包括分层随机中误选分层因素所导致的操作偏差、多中心试验中存在中心样本量不足问题下的竞争分层设计挑战,以及动态随机化方法中最小化概率设置的参数选择问题。通过模拟方法评估不同设定下的分组质量变化,为随机化方案的优化设计和实施质量控制提供参考依据。方法:采用蒙特卡洛模拟方法,构建3类典型问题场景,包括分层区组随机中误选分层因素、中心平均样本量不足情境下的中心竞争区组设计,及最小化随机中最大容许不平衡性(MTI)与最优分配概率的选择。通过多轮模拟,评估不同设定下的分层均衡性(SI)、层内组间均衡性(GI)、组间例数最大差值(MI)及猜对分配概率(CG)指标。结果:在合理误差范围内,3种问题场景下模拟均未显著破坏随机化的整体均衡性与随机性,符合临床试验质量要求。误选分层因素在组合层较多、每层样本稀疏情境下,可能引发局部层内不均衡,但整体影响有限。“前期中心竞争区组+后期打破区组”的策略,在中心数量较多[中心样本量系数(CSC)>10%]的研究中可保持较好均衡性,但需关注各中心入组节奏。动态随机中,最优分配概率与随机性呈负相关,推荐设置在0.6~0.667,MTI控制在2~3,以实现平衡性与随机性的合理折中。结论:本研究系统揭示了3类常见随机化情境对随机分配质量的潜在影响,提出了具体参数建议与操作优化策略。研究结果可为临床试验随机化实施的规范化、稳健性提升提供实践指导。 展开更多
关键词 随机对照试验 随机分配 分组均衡性 分层区组设计 中心效应 最小化随机法 模拟研究
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ULCV分布式配电网集约化+总段化的集成设计方法 认领 引用
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作者 黄雪锋 《造船技术》 2026年第4期1-7,共7页
针对传统馈线式配电网设计方法存在的问题,以某14000 TEU超大型集装箱船(Ultra Large Container Vessel,ULCV)为例,基于分布式与传统馈线式的配电网设计效果对比,提出一种ULCV分布式配电网集约化+总段化的集成设计方法。采用该方法进行... 针对传统馈线式配电网设计方法存在的问题,以某14000 TEU超大型集装箱船(Ultra Large Container Vessel,ULCV)为例,基于分布式与传统馈线式的配电网设计效果对比,提出一种ULCV分布式配电网集约化+总段化的集成设计方法。采用该方法进行分布式配电网的上层建筑区域集约化设计、独立货舱区域集约化设计和电缆册总段化设计。该方法可实现各功能区域电缆敷设作业由船坞串行作业改为平台并行同步作业,不仅可大幅降低因电缆冗余设计产生的采购成本,而且可有效提高船舶建造效率。 展开更多
关键词 超大型集装箱船 分布式配电网 集约化设计 总段化设计 上层建筑区域 独立货舱区域 电缆册 电缆敷设
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Interaction Between Memory Load and Experimental Design on Brain Connectivity and Network Topology 认领 引用 被引量：1
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作者 Heming Zhang Xin Di +3 位作者 Bart Rypma Hang Yang Chun Meng Bharat Biswal 《Neuroscience Bulletin》 SCIE CAS CSCD 2023年第4期631-644,共14页
The conventional approach to investigating functional connectivity in the block-designed study usually concatenates task blocks or employs residuals of task activation.While providing many insights into brain function... The conventional approach to investigating functional connectivity in the block-designed study usually concatenates task blocks or employs residuals of task activation.While providing many insights into brain functions,the block design adds more manipulation in functional network analysis that may reduce the purity of the blood oxygenation level-dependent signal.Recent studies utilized one single long run for task trials of the same condition,the so-called continuous design,to investigate functional connectivity based on task functional magnetic resonance imaging.Continuous brain activities associated with the single-task condition can be directly utilized for task-related functional connectivity assessment,which has been examined for working memory,sensory,motor,and semantic task experiments in previous research.But it remains unclear how the block and continuous design influence the assessment of task-related functional connectivity networks.This study aimed to disentangle the separable effects of block/continuous design and working memory load on task-related functional connectivity networks,by using repeated-measures analysis of variance.Across 50 young healthy adults,behavioral results of accuracy and reaction time showed a significant main effect of design as well as interaction between design and load.Imaging results revealed that the cingulo-opercular,fronto-parietal,and default model networks were associated with not only task activation,but significant main effects of design and load as well as their interaction on intra-and inter-network functional connectivity and global network topology.Moreover,a significant behavior-brain association was identified for the continuous design.This work has extended the evidence that continuous design can be used to study task-related functional connectivity and subtle brain-behavioral relationships. 展开更多
关键词 Working memory Functional connectivity Network topology Block design Continuous design Memory load
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基于区组设计的Piggybacking编码构造 认领 引用
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作者 李瞳 王静 +2 位作者 张洁薇 杨红志 刘向阳 《上海交通大学学报》 EI CAS CSCD 北大核心 2026年第1期100-111,共12页
现有Piggybacking编码在最大距离可分(MDS)码的基础上能够有效减小信息节点的修复带宽开销,但存在修复度大、校验节点修复带宽高等问题,同时忽略了实际分布式存储系统中数据冷热程度的差异.为此提出一种基于区组设计的Piggybacking编码... 现有Piggybacking编码在最大距离可分(MDS)码的基础上能够有效减小信息节点的修复带宽开销,但存在修复度大、校验节点修复带宽高等问题,同时忽略了实际分布式存储系统中数据冷热程度的差异.为此提出一种基于区组设计的Piggybacking编码构造,对热数据节点提供更高等级的保护,采用区组设计,对冷热数据节点进行非均匀分组,将热数据符号捎带到对应校验节点中,通过一定规则生成冷、热数据校验块和斜校验块.理论分析与实验仿真发现,与现有Piggybacking编码相比,基于区组设计的Piggybacking编码显著降低了故障节点的平均修复带宽率和平均修复度率;且相较于冷数据节点,热数据节点的修复带宽开销更低. 展开更多
关键词 Piggybacking编码 区组设计 冷热数据 修复带宽 修复度
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汽车热交换系统直管口水室模具设计 认领 引用
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作者 叶卫文 姜炳春 +1 位作者 冯婧 陈镇森 《中国塑料》 CAS CSCD 北大核心 2026年第2期106-113,共8页
聚焦于汽车热交换系统中直管口水室塑件的模具设计难题,提出一种创新的滑块双斜顶复合结构模具。通过对制件结构与成型难点的深入剖析,阐述了针对该塑件的模具设计方案,涵盖浇口、脱模、分型等关键部分,并详细介绍模具工作过程。对比传... 聚焦于汽车热交换系统中直管口水室塑件的模具设计难题,提出一种创新的滑块双斜顶复合结构模具。通过对制件结构与成型难点的深入剖析,阐述了针对该塑件的模具设计方案,涵盖浇口、脱模、分型等关键部分,并详细介绍模具工作过程。对比传统模具,突出本设计在结构和预变形技术方面的创新点,同时对模具的不良率和适用性进行分析。结果表明,该模具设计有效解决了直管口水室塑件的成型难题,提升了产品质量和生产效率,为汽车零部件模具设计提供了新的思路与方法。 展开更多
关键词 汽车热交换系统 滑块双斜顶复合结构 模具设计 预变形技术
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