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TPA改进GCN⁃LSTM的光伏电站群调群控优化策略研究
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作者 商立群 王硕 《电气传动》 2026年第3期52-60,共9页
随着光伏装机容量占比逐年提高,准确预测光伏出力,实现光伏群调群控至关重要。提出基于图卷积神经网络(GCN)、长短期记忆网络(LSTM)和时间模式注意力机制(TPA)集成深度融合的多站光伏出力预测方法。首先,以图结构形式转化多站光伏出力... 随着光伏装机容量占比逐年提高,准确预测光伏出力,实现光伏群调群控至关重要。提出基于图卷积神经网络(GCN)、长短期记忆网络(LSTM)和时间模式注意力机制(TPA)集成深度融合的多站光伏出力预测方法。首先,以图结构形式转化多站光伏出力时序曲线及数值天气预报数据的输入特征,建立GCN-LSTM模型,提取光伏集群间隐藏的时空依赖性。其次,引入时间模式注意力机制加权修正输入数据特征,提高关键数据价值。然后,设定反映集群内电压变化的节点为主导节点,基于光伏集群间时空预测结果,将灵敏反映集群电压变化的节点设定为主导节点,建立区域所有节点的电压在安全范围运行和最小系统网损为目标的群间协调优化策略。接着,根据协调优化策略结果构建群内节点电压在安全范围内稳定运行、最小化集群网损的自治优化调控策略,实现分布式光伏最大化就地消纳。最后,实际多站光伏集群出力数据的仿真结果表明,所提方法能够高效提取不同光伏电站间的时空关联性,降低光伏出力预测误差,有效提高光伏集群的安全性和经济性。 展开更多
关键词 光伏出力预测 图卷积神经网络 邻接矩阵自适应 时间模式注意力机制
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3,5,6-TPA促进荔枝果实增大和成熟的原因分析
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作者 黄志强 刘旋 +3 位作者 严婷 邓嘉辉 赵明磊 李建国 《果树学报》 北大核心 2026年第1期122-135,共14页
【目的】探究全树喷施40 mg·L^(-1)3,5,6-三氯-2-吡啶氧乙酸(3,5,6-TPA)对荔枝果实生长发育的调控作用及其潜在原因。【方法】以砧木为妃子笑的16年生的仙进奉为试验材料,在荔枝花后5周全树喷施浓度(ρ,后同)为40 mg·L^(-1)3,... 【目的】探究全树喷施40 mg·L^(-1)3,5,6-三氯-2-吡啶氧乙酸(3,5,6-TPA)对荔枝果实生长发育的调控作用及其潜在原因。【方法】以砧木为妃子笑的16年生的仙进奉为试验材料,在荔枝花后5周全树喷施浓度(ρ,后同)为40 mg·L^(-1)3,5,6-TPA,测定和分析果实主要的生理和品质指标。【结果】喷施3,5,6-TPA能够显著增大仙进奉荔枝果实,促使果实提前1周成熟,对果实的内在品质没有显著影响。3,5,6-TPA处理促进果实增大的潜在原因包括:(1)短暂抑制了荔枝叶片的光合作用,导致部分果实在早期发育阶段受阻,后期发生脱落,起到了类似疏果的作用。(2)提高了果实发育前期果皮、假种皮和种子中的内源IAA含量。(3)增强了细胞壁转化酶、酸性转化酶、中性转化酶以及蔗糖磷酸合成酶活性,进而促进了糖分的积累。促进果实成熟提前的潜在原因包括:(1)提高了果实发育期间果皮、假种皮和种子中内源ABA含量。(2)促进了果实成熟期间内源IAA含量的提前下降。【结论】3,5,6-TPA可以在仙进奉荔枝的内在品质无显著影响的情况下,短暂抑制荔枝叶片净光合速率,改变假种皮中相关代谢酶活性,调控果实中各组织内源IAA、ABA含量,从而有效增加荔枝的果实大小和提高优质果率,促进果实提前成熟。 展开更多
关键词 荔枝 3 5 6-tpa 果实大小 果实成熟 果实品质
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基于穿刺法和TPA法分析荔枝果实质构特性
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作者 李春燕 史发超 +3 位作者 文英杰 刘海伦 严倩 姜永华 《果树学报》 北大核心 2026年第2期439-456,共18页
【目的】探索测试荔枝果实质构特性的条件和方法,为荔枝果实质地评价提供理论依据。【方法】利用物性分析仪系统研究了穿刺和质地多面分析法(texture profile analysis,TPA)不同测试参数对荔枝质构测定的影响,以最佳测试参数对8个荔枝... 【目的】探索测试荔枝果实质构特性的条件和方法,为荔枝果实质地评价提供理论依据。【方法】利用物性分析仪系统研究了穿刺和质地多面分析法(texture profile analysis,TPA)不同测试参数对荔枝质构测定的影响,以最佳测试参数对8个荔枝品种展开应用分析,并分析各质构参数间的相关性。【结果】以水东荔枝为样品进行单因素试验,穿刺法检测荔枝果皮质地的最佳参数设置为穿刺深度4 mm、测试速度0.5 mm·s^(-1)、触发力0.38 N;TPA测试荔枝整果(带皮和去皮)的最佳测试水平为形变量20%、测试速度0.5 mm·s^(-1)、触发力0.38 N。果皮强度与果皮最大位移、穿刺果皮做功呈极显著正相关(P<0.01);果肉硬度与咀嚼性呈极显著正相关(P<0.01),与内聚性、回复性呈极显著负相关(P<0.01);弹性和咀嚼性呈极显著正相关(P<0.01)。利用主成分分析从20个指标(质构仪参数指标)中提取到5个因子,累计方差贡献率为86.26%,得分图显示分类效果良好,载荷值高的各重要指标(如果肉硬度、果肉咀嚼性和果肉挤压做功)可用于区分不同荔枝果实的质地特征。【结论】该研究初步建立了量化评价荔枝果实质地品质的方法,穿刺法和TPA法结合能有效区分不同种质间质地差异,丰富了荔枝质地评价内容。 展开更多
关键词 荔枝 穿刺法 质地多面分析法(tpa) 果实质地 种质资源
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疏血通与银杏叶制剂联合TNK-tPA治疗老年急性缺血性脑卒中患者的疗效
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作者 徐飞飞 楚海波 《临床研究》 2026年第3期104-107,共4页
目的探讨疏血通注射液与银杏叶制剂联合替奈普酶(TNK-tPA)治疗老年急性缺血性脑卒中患者的临床效果。方法选取2023年1月至2024年12月期间郑州市金水区总医院收治的84例老年急性缺血性脑卒中患者,按照随机数字表法分为对照组和观察组,每... 目的探讨疏血通注射液与银杏叶制剂联合替奈普酶(TNK-tPA)治疗老年急性缺血性脑卒中患者的临床效果。方法选取2023年1月至2024年12月期间郑州市金水区总医院收治的84例老年急性缺血性脑卒中患者,按照随机数字表法分为对照组和观察组,每组42例。对照组采用银杏叶制剂联合TNK-tPA治疗,观察组在对照组治疗基础上加用疏血通注射液。所有研究用药均在溶栓后24 h、复查头颅影像排除出血后启动。两组均于治疗后第14 d进行疗效评估。比较两组中医症状积分、美国国立卫生研究院卒中量表(NIHSS)评分、血液流变学指标及治疗安全性。结果观察组治疗有效率高于对照组,差异有统计学意义(P<0.05)。治疗后,两组各项中医症状积分、NIHSS评分、血液流变学指标(全血低切还原黏度、血浆黏度、全血高切还原黏度、血细胞比容)均降低,且观察组低于对照组,差异有统计学意义(P<0.05)。两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论对于瘀血阻络型老年急性缺血性脑卒中患者,疏血通注射液与银杏叶制剂联合TNK-tPA的治疗方案与中医证候和神经功能的更大幅度改善相关,提示其在对照组治疗基础上可能为患者带来额外获益。 展开更多
关键词 老年 急性缺血性脑卒中 瘀血阻络型 疏血通 银杏叶制剂 TNK-tpa 疗效
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曲克芦丁联合r-tPA治疗超时间窗急性缺血性脑卒中的临床研究 被引量:1
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作者 武岳 董芬芬 +4 位作者 唐灵芝 秦敏 刘婷 屈斐 黄运芳 《保健医学研究与实践》 2025年第5期121-126,共6页
目的探讨曲克芦丁联合重组组织型纤溶酶原激活剂(r-tPA)治疗超时间窗(发病后4.5~8 h)急性缺血性脑卒中(AIS)的临床效果,以期为超时间窗AIS患者的治疗提供参考。方法选取2022年1月—2024年5月在陕西省商洛市中心医院接受治疗的236例超时... 目的探讨曲克芦丁联合重组组织型纤溶酶原激活剂(r-tPA)治疗超时间窗(发病后4.5~8 h)急性缺血性脑卒中(AIS)的临床效果,以期为超时间窗AIS患者的治疗提供参考。方法选取2022年1月—2024年5月在陕西省商洛市中心医院接受治疗的236例超时间窗AIS患者,采用随机数字表法分为对照组和研究组,每组118例。在常规治疗基础上,对照组患者接受r-tPA治疗,研究组患者接受曲克芦丁联合r-tPA治疗,2组患者均持续治疗2周。比较2组患者治疗前后的脑血流动力学指标、脑血流灌注指标、血清因子水平、神经功能恢复情况和90 d预后,以及药物不良反应发生情况。结果治疗前,2组患者平均血流速度(Vm)、舒张末期血流速度(Vd)和收缩期峰值血流速度(Vp)水平比较,差异均无统计学意义(P>0.05);治疗后,2组患者Vm、Vd和Vp水平均高于治疗前,且研究组均高于对照组,差异均有统计学意义(P<0.05)。治疗前,2组患者平均通过时间(MTT)、脑血流容积(CBV)和脑血流量(CBF)水平比较,差异均无统计学意义(P>0.05);治疗后,2组患者CBV和CBF水平均高于治疗前且研究组均高于对照组,MTT均短于治疗前且研究组短于对照组,差异均有统计学意义(P<0.05)。治疗前,2组患者血清可溶性Fas(sFas)和可溶性Fas配体(sFasL)水平比较,差异均无统计学意义(P>0.05);治疗后,2组患者血清sFas和sFasL水平均低于治疗前,且研究组均低于对照组,差异均有统计学意义(P<0.05)。治疗前,2组患者美国国立卫生研究院卒中量表(NIHSS)评分和改良Rankin量表(mRS)评分比较,差异均无统计学意义(P>0.05);治疗后,2组患者NIHSS评分和mRS评分均低于治疗前,且研究组均低于对照组,差异均有统计学意义(P<0.05)。研究组和对照组患者的不良反应发生率分别为13.56%(16/118)和9.32%(11/118),差异无统计学意义(χ^(2)=1.046,P=0.307)。研究组和对照组患者随访90 d病死率分别为1.69%(2/118)和2.54%(3/118),差异无统计学意义(χ^(2)=0.000,P=1.000)。结论曲克芦丁联合r-tPA治疗用于超时间窗AIS患者,可改善其脑血流动力学指标、脑血流灌注和神经功能,从而改善患者预后且不会增加不良反应发生风险。 展开更多
关键词 曲克芦丁 重组组织型纤溶酶原激活剂治疗 溶栓时间窗 急性缺血性脑卒中 神经功能
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Component-based Control Software Design for Flexible Manufacturing System 被引量:4
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作者 周炳海 奚立峰 曹永上 《Journal of Donghua University(English Edition)》 EI CAS 2003年第1期81-85,共5页
A new method that designs and implements the component-based distributed & hierarchical flexible manufacturing control software is described with a component concept in this paper. The proposed method takes aim at... A new method that designs and implements the component-based distributed & hierarchical flexible manufacturing control software is described with a component concept in this paper. The proposed method takes aim at improving the flexibility and reliability of the control system. On the basis of describing the concepts of component-based software and the distributed object technology, the architecture of the component-based software of the control system is suggested with the Common Object Request Broker Architecture (CORBA). And then, we propose a design method for component-based distributed & hierarchical flexible manufacturing control system. Finally, to verify the software design method, a prototype flexible manufacturing control system software has been implemented in Orbix 2.3c, VC + + 6. 0 and has been tested in connection with the physical flexible manufacturing shop at the WuXi Professional Institute. 展开更多
关键词 component-based software Control systems Flexible manufacturing system distributed object.
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Component-based software reliability process simulation considering imperfect debugging 被引量:2
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作者 张策 Cui Gang +1 位作者 Bian Yali Liu Hongwei 《High Technology Letters》 EI CAS 2014年第1期9-15,共7页
In view of the flaws of component-based software (CBS) reliability modeling and analysis, the low recognition degree of debugging process, too many assumptions and difficulties in obtaining the solution, a CBS relia... In view of the flaws of component-based software (CBS) reliability modeling and analysis, the low recognition degree of debugging process, too many assumptions and difficulties in obtaining the solution, a CBS reliability simulation process is presented incorporating the imperfect debugging and the limitation of debugging resources. Considering the effect of imperfect debugging on fault detec- tion and correction process, a CBS integration testing model is sketched by multi-queue muhichannel and finite server queuing model (MMFSQM). Compared with the analytical method based on pa- rameters and other nonparametric approaches, the simulation approach can relax more of the usual reliability modeling assumptions and effectively expound integration testing process of CBS. Then, CBS reliability process simulation procedure is developed accordingly. The proposed simulation ap- proach is validated to be sound and effective by simulation experiment studies and analysis. 展开更多
关键词 software reliability growth model (SRGM) component-based software (CBS) imperfect debugging reliability simulation queuing theory
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基于TPA法与感官评价法研究果蔬冻干前后质地变化 被引量:1
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作者 王燕 杨丽 +3 位作者 刘新琦 马依楠 张华启 罗效糠 《中国果菜》 2025年第6期12-19,共8页
通过质地剖面分析法(texture profile analysis,TPA)与传统感官评价法,分析果蔬冻干前后果实质地变化,并探讨了TPA法作为仪器测定方法替代感官评价的可行性。研究对象包括7种水果(菠萝、火龙果、猕猴桃、柠檬、苹果、水蜜桃、香蕉)与3... 通过质地剖面分析法(texture profile analysis,TPA)与传统感官评价法,分析果蔬冻干前后果实质地变化,并探讨了TPA法作为仪器测定方法替代感官评价的可行性。研究对象包括7种水果(菠萝、火龙果、猕猴桃、柠檬、苹果、水蜜桃、香蕉)与3种蔬菜(胡萝卜、黄瓜、秋葵)。结果表明,多数果蔬冻干后硬度显著增加(菠萝、水蜜桃等),少数蔬菜冻干后硬度下降(胡萝卜、秋葵),而内聚性、弹性和咀嚼性变化趋势不一。对冻干前后TPA质地参数变化的相关性进行分析发现,苹果、菠萝、水蜜桃、香蕉在新鲜状态下弹性和咀嚼性呈显著相关,但冻干后相关性减弱;而猕猴桃、秋葵在冻干后弹性和咀嚼性仍呈现显著正相关,可能与冻干过程中水分流失有关。TPA测定结果与感官评价高度一致,硬度、弹性和咀嚼性等参数可有效定量评价冻干后果蔬质地变化。 展开更多
关键词 果蔬 传统感官评价 tpa 冻干
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CCPA: Component-based communication protocol architecture for embedded systems
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作者 戴鸿君 陈天洲 陈纯 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第B08期79-86,共8页
For increased and various communication requirements of modem applications on embedded systems, general purpose protocol stacks and protocol models are not efficient because they are fixed to execute in the static mod... For increased and various communication requirements of modem applications on embedded systems, general purpose protocol stacks and protocol models are not efficient because they are fixed to execute in the static mode. We present the Component-Based Communication Protocol Architecture (CCPA) to make communication dynamic and configurable. It can develop, test and store the customized components for flexible reuse. The protocols are implemented by component assembly and support by configurable environments. This leads to smaller memory, more flexibility, more reconfiguration ability, better concurrency, and multiple data channel support. 展开更多
关键词 component-based Protocol component-based Protocol Architecture (CCPA) Dynamic configuration Embedded communication system
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Component-Based Software Trustworthiness Fuzzy Analytic Hierarchy Process Model
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作者 石剑飞 闫怀志 +1 位作者 秦玮 王文同 《Journal of Beijing Institute of Technology》 EI CAS 2010年第2期170-176,共7页
For a more accurate and comprehensive assessment of the trustworthiness of component-based soft- ware system, the fuzzy analytic hierarchy process is introduced to establish the analysis model. Combine qualitative and... For a more accurate and comprehensive assessment of the trustworthiness of component-based soft- ware system, the fuzzy analytic hierarchy process is introduced to establish the analysis model. Combine qualitative and quantitative analyses, the impacts to overall trustworthiness by the different types of components are distinguished. Considering the coupling relationship between components, dividing the system into several layers from target layer to scheme layer, evaluating the scheme advantages disadvantages by group decision-making, the trustworthiness of a typical J2EE structured component-based software is assessed. The trustworthiness asses model of the software components provides an effective methods of operation. 展开更多
关键词 component-based software trustworthiness analysis fuzzy analytic hierarchy process J2EE structure
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Component-based software reliability analysis incorporating imperfect debugging and change-point
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作者 张策 Cui Gang +2 位作者 Liu Hongwei Meng Fanchao Bian Yali 《High Technology Letters》 EI CAS 2014年第4期346-354,共9页
Against the deficiencies of component-based software(CBS) reliability modeling and analysis,for instance,importing too many assumptions,paying less attention to debugging process without considering imperfect debuggin... Against the deficiencies of component-based software(CBS) reliability modeling and analysis,for instance,importing too many assumptions,paying less attention to debugging process without considering imperfect debugging and change-point(CP) problems adequately,an approach of CBS reliability process analysis is proposed which incorporates the imperfect debugging and CP.First,perfect/imperfect debugging and CP are reviewed.Based on the queuing theory,a multi-queue multichannel and infinite server queuing model(MMISQM) is presented to sketch the integration test process of CBS.Meanwhile,considering the effects of imperfect debugging and CP,expressions for fault detection and correction are derived based on MMISQM.Numerical results demonstrate that the proposed model can sketch the integration test process of CBS with preferable performance which outperforms other models. 展开更多
关键词 software reliability component-based software (CBS) imperfect debugging change-point (CP) queuing theory
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A software reliability growth model for component-based software incorporating debugging delay and imperfect debugging
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作者 张策 Cui Gang +2 位作者 Meng Fanchao Liu Hongwei Bian Yali 《High Technology Letters》 EI CAS 2015年第1期54-62,共9页
In view of the problems and the weaknesses of component-based software ( CBS ) reliability modeling and analysis, and a lack of consideration for real debugging circumstance of integration tes- ting, a CBS reliabili... In view of the problems and the weaknesses of component-based software ( CBS ) reliability modeling and analysis, and a lack of consideration for real debugging circumstance of integration tes- ting, a CBS reliability process analysis model is proposed incorporating debugging time delay, im- perfect debugging and limited debugging resources. CBS integration testing is formulated as a multi- queue muhichannel and finite server queuing model (MMFSQM) to illustrate fault detection process (FDP) and fault correction process (FCP). A unified FCP is sketched, given debugging delay, the diversities of faults processing and the limitations of debugging resources. Furthermore, the impacts of imperfect debugging on fault detection and correction are explicitly elaborated, and the expres- sions of the cumulative number of fault detected and corrected are illustrated. Finally, the results of numerical experiments verify the effectiveness and rationality of the proposed model. By comparison, the proposed model is superior to the other models. The proposed model is closer to real CBS testing process and facilitates software engineer' s quantitatively analyzing, measuring and predicting CBS reliability. K 展开更多
关键词 software reliability component-based software (CBS) debugging delay imper- fect debugging queuing theory
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A component-based back-propagation reliability model with low complexity for complex software systems
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作者 聂鹏 Geng Ji Qin Zhiguang 《High Technology Letters》 EI CAS 2013年第3期273-282,共10页
Since most of the available component-based software reliability models consume high computational cost and suffer from the evaluating complexity for the software system with complex structures,a component-based back-... Since most of the available component-based software reliability models consume high computational cost and suffer from the evaluating complexity for the software system with complex structures,a component-based back-propagation reliability model(CBPRM)with low complexity for the complex software system reliability evaluation is presented in this paper.The proposed model is based on the artificial neural networks and the component reliability sensitivity analyses.These analyses are performed dynamically and assigned to the neurons to optimize the reliability evaluation.CBPRM has a linear increasing complexity and outperforms the state-based and the path-based reliability models.Another advantage of CBPRM over others is its robustness.CBPRM depends on the component reliabilities and the correlative sensitivities,which are independent from the software system structure.Based on the theory analysis and experiment results,it shows that the complexity of CBPRM is evidently lower than the contrast models and the reliability evaluating accuracy is acceptable when the software system structure is complex. 展开更多
关键词 software reliability evaluation component-based software system component reli-ability sensitivity artificial neural networks
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Reliability Evaluation Optimal Selection Model of Component-Based System
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作者 Guo Yong Wan Tian Tian +1 位作者 Ma Pei Jun Su Xiao Hong 《Journal of Software Engineering and Applications》 2011年第7期433-441,共9页
If the components in a component-based software system come from different sources, the characteristics of the components may be different. Therefore, evaluating the reliability of a component-based system with a fixe... If the components in a component-based software system come from different sources, the characteristics of the components may be different. Therefore, evaluating the reliability of a component-based system with a fixed model for all components will not be reasonable. To solve this problem, this paper combines a single reliability growth model with an architecture-based reliability model, and proposes an optimal selecting approach. First, the most appropriate model of each component is selected according to the historical reliability data of the component, so that the evaluation deviation is the smallest. Then, system reliability is evaluated according to both the relationships among components and the using frequency of each component. As the approach takes into account the historical data and the using frequency of each component, the evaluation and prediction results are more accurate than those of using a single model. 展开更多
关键词 OPTIMAL EVALUATION Approach LIKELIHOOD Estimation Reliability EVALUATION component-based SYSTEM OPTIMAL SELECTION Model (OSM)
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Testing Component-Based Software: What It has to do with Design and Component Selection
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作者 Shyam S. Pandeya Anil K. Tripathi 《Journal of Software Engineering and Applications》 2011年第1期37-47,共11页
In a component-based software development life cycle, selection of preexisting components is an important task. Every component that has to be reused has an associated risk of failure of not meeting the functional and... In a component-based software development life cycle, selection of preexisting components is an important task. Every component that has to be reused has an associated risk of failure of not meeting the functional and non-functional requirements. A component's failure would lead a developer to look for some other alternative of combinations of COTS, in-house and engineered components among possible candidate combinations. This means design itself can readily change. The very process of design of a software system and component selection seems to be heavily dependent on testing results. Instability of design, further, becomes more severe due to requirements change requests. Therefore, this instability of design has to be essentially mitigated by using proper design and testing approaches, otherwise, it may lead to exorbitantly high testing cost due to the repeated testing of various alternatives. How these three activities: Component-based software design, component selection and component-based software testing are interrelated? What process model is most suited to address this concern? This work explores the above questions and their implication in terms of nature of a process model that can be convincing in case of component-based software development. 展开更多
关键词 CBSE (component-based SOFTWARE Engineering) SOFTWARE TESTING SOFTWARE Process COTS (Commercial Off-The-Shelf Software)
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汽车连接器典型TPA插拔力研究
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作者 杜艳平 王武军 王志广 《汽车电器》 2025年第7期109-113,116,共6页
为实现两端固定型TPA一次设计成功率的目标,并精准预测其插拔力,文章先对两端固定型TPA开展全面深入的理论研究,严谨进行公式推导;接着通过科学的方法拟合出修正系数,从而完成插拔力计算公式的最终确定;最后针对所推导的理论公式进行试... 为实现两端固定型TPA一次设计成功率的目标,并精准预测其插拔力,文章先对两端固定型TPA开展全面深入的理论研究,严谨进行公式推导;接着通过科学的方法拟合出修正系数,从而完成插拔力计算公式的最终确定;最后针对所推导的理论公式进行试验验证。验证结果表明:插拔力的计算结果与试验结果的一致性高达85%。该研究成果对典型TPA的设计具有极为重要的指导意义,能有效助力TPA设计工作的科学开展与高效推进。 展开更多
关键词 tpa 插拔力 修正系数
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基于TPA的某皮卡车道路噪声问题诊断及优化
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作者 李芳杰 杨曼 +2 位作者 赵飞 刁硕 孙骏竹 《计算机辅助工程》 2025年第2期41-46,共6页
为解决某皮卡车样车的道路噪声问题,采用轮心力加载法对皮卡车道路噪声进行仿真和优化。实验测量特定速度下的轮心加速度响应,仿真计算轮心到测点的传递函数,利用逆矩阵和主分量分析(principle components analysis,PCA)理论,获得轮心力... 为解决某皮卡车样车的道路噪声问题,采用轮心力加载法对皮卡车道路噪声进行仿真和优化。实验测量特定速度下的轮心加速度响应,仿真计算轮心到测点的传递函数,利用逆矩阵和主分量分析(principle components analysis,PCA)理论,获得轮心力的24个线性无关的主分量结果,并将其加载到整车仿真模型中,得到与实验较吻合的道路噪声结果。结合传递路径分析(transfer path analysis,TPA)思路,提出快速诊断道路噪声峰值的方法,从而有效定位问题点。该皮卡车底盘衬套刚度优化结果证明本文诊断和优化流程的有效性。 展开更多
关键词 轮心力 逆矩阵 传递路径分析(tpa) 底盘模态 衬套刚度 参数优化
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基于时频域信号优化器的Mi-MkTCN轴承寿命预测模型
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作者 刘毅 高雪莲 +3 位作者 李一弘 王永琦 孔玲丽 康立军 《现代制造工程》 北大核心 2026年第2期117-128,共12页
滚动轴承是机械设备中的常见关键部件,准确预测其剩余使用寿命对机械设备的安全稳定运行至关重要。针对目前轴承寿命预测存在的轴承退化特征不明显、模型泛化能力差以及数据长期依赖关系难以捕捉的问题,提出基于时频域信号优化器(Time-F... 滚动轴承是机械设备中的常见关键部件,准确预测其剩余使用寿命对机械设备的安全稳定运行至关重要。针对目前轴承寿命预测存在的轴承退化特征不明显、模型泛化能力差以及数据长期依赖关系难以捕捉的问题,提出基于时频域信号优化器(Time-Frequency domain signal Ratio Optimizer,TFRO)的多重膨胀多核时间卷积网络(Multi inflated Multi kernel Time Convolutional Network,Mi-MkTCN)模型。TFRO优化器为了精准记忆重要信息,在每一个时间节点上,将过去信息和当前信息重组,其中过去信息中的重要的时频域特征经过了有比例的分配。Mi-MkTCN利用多重膨胀确保重要特征不丢失,再利用多核时间卷积网络实现对不同尺度特征的提取。最终的消融对比实验验证了改进方法的有效性,模型的平均绝对误差、均方误差及均方根误差指标分别为0.00145、0.05069和0.12045。实验结果表明,所提方法显著提升了轴承剩余使用寿命的预测精度,为轴承剩余使用寿命预测提供了高精度、高鲁棒性的解决方案。 展开更多
关键词 时频域信号比例优化器 精准记忆tpa 多重膨胀 多核时间卷积网络 轴承剩余使用寿命预测
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r-TPA眼内注射对眼球破裂伤患者玻璃体切割手术效果影响分析
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作者 庄绍熙 肖正霞 +1 位作者 韩贝贝 刘建伟 《国际眼科杂志》 2025年第12期2052-2055,共4页
目的:探讨经平坦部玻璃体切割手术(PPV)术前玻璃体腔注射重组组织纤溶酶原激活剂(r-TPA)对眼球破裂伤(RG)患者手术效果的影响。方法:回顾性地收集2020年4月至2023年11月本院Ⅰ期缝合稳定后7-10 d行PPV的RG患者37例37眼,根据PPV术前1 d... 目的:探讨经平坦部玻璃体切割手术(PPV)术前玻璃体腔注射重组组织纤溶酶原激活剂(r-TPA)对眼球破裂伤(RG)患者手术效果的影响。方法:回顾性地收集2020年4月至2023年11月本院Ⅰ期缝合稳定后7-10 d行PPV的RG患者37例37眼,根据PPV术前1 d是否行玻璃体腔注射r-TPA,分为术前注射r-TPA组14例14眼及术前未注射r-TPA组23例23眼。比较两组患者PPV术中视网膜复位率、术中硅油应用情况、术后眼内再出血、术后低眼压及最佳矫正视力情况。结果:两组患者术前一般资料具有可比性(P>0.05)。两组患者术中视网膜复位率、硅油填充量及术后最佳矫正视力占比均有差异(均P<0.05),两组术中硅油填充率、术后眼内再出血情况、术后低眼压发生率无差异(均P>0.05)。结论:PPV术前1 d接受r-TPA眼内注射的RG患者术中视网膜复位率和术后视力改善率更高。 展开更多
关键词 眼球破裂伤 重组组织纤溶酶原激活剂(r-tpa) 玻璃体切割手术
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松花菜种质花球质地品质的评价
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作者 陈敏氡 裘波音 +2 位作者 黄昊 李永平 温庆放 《中国农业科学》 北大核心 2026年第6期1302-1316,共15页
【目的】通过对松花菜种质资源花球质地性状数据的分析,建立统一、客观的松花菜花球质地评价方法,并研究影响花球质地的潜在因素,以期为松花菜食用品质评价和品质育种提供参考。【方法】应用质地多面剖析法(TPA)和感官评价法对166份松... 【目的】通过对松花菜种质资源花球质地性状数据的分析,建立统一、客观的松花菜花球质地评价方法,并研究影响花球质地的潜在因素,以期为松花菜食用品质评价和品质育种提供参考。【方法】应用质地多面剖析法(TPA)和感官评价法对166份松花菜种质资源进行评价,获得5种TPA指标(硬度、内聚性、弹性、咀嚼性和回复性)和3种感官评价指标(感官脆度、感官硬度和感官咀嚼性)数据,开展相关性分析和线性回归分析,构建感官评价指标与质地参数间的关系模型,并通过主成分分析、隶属函数分析和聚类分析,建立松花菜花球质地评价数学模型,划分松花菜种质资源的质地类群。进一步分析不同类群松花菜花球的细胞微观结构、细胞壁组分含量的差异,探究影响松花菜花球质地的潜在因素。【结果】8个花球质地指标在不同松花菜种质间差异显著,其中,咀嚼性指标的离散程度最大。感官评价指标与TPA指标之间存在不同程度的正相关性,通过构建二者的线性回归方程,发现硬度在感官质地评价中具有重要预测价值。采用主成分分析提取2个影响松花菜花球质地的主成分,累计贡献率达90.22%,其中,第一主成分主要包括硬度、咀嚼性和弹性,是决定松花菜的适口性的重要参数。建立松花菜花球质地评价数学模型:质地综合得分值C=-2.045+0.017×咀嚼性+3.108×回复性+0.555×弹性+0.010×硬度+1.950×内聚性。依据C值将166份松花菜种质资源分为3种质地类型,第Ⅰ类群花球C值最低(0.01≤C≤0.35),呈现低硬度、咀嚼性差的特征,属绵软型;第Ⅱ类群花球C值居中(0.37≤C≤0.62),质地均衡且适口性良好,属脆嫩型;第Ⅲ类群花球C值最高(0.65≤C≤1.00),表现为较高的硬度、弹性与咀嚼性,属脆弹型。不同质地的松花菜花球在细胞结构和细胞壁成分上存在显著差异,脆弹型松花菜花球细胞圆度较高、结构紧密,纤维素与半纤维素含量较高;脆嫩型松花菜花球细胞形态饱满、结构均匀,其纤维素、半纤维素和可溶性果胶含量比例适中;绵软型松花菜花球则具有明显的细胞孔隙和疏松结构,可溶性果胶含量偏高。【结论】建立松花菜花球质地评价数学模型:C=-2.045+0.017×咀嚼性+3.108×回复性+0.555×弹性+0.010×硬度+1.950×内聚性,划分出不同松花菜花球质地类型的C值范围可用于松花菜种质资源的鉴定,细胞结构和细胞壁组成物质对松花菜花球的质地品质具有重要影响。 展开更多
关键词 松花菜 种质资源 花球质地评价 质地多面剖析法 感官评价法
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