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基于PROMETHEE-Ⅱ的电网科技项目后评估评价方法研究
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作者 王建军 张婷 李存斌 《黑龙江电力》 CAS 2024年第2期151-157,共7页
为满足双碳背景下电网精准投资的迫切需求,面对目前电网科技项目数量的急剧增加,迫切需要构建一个后评价指标体系,以低碳绿色发展、运营效率和经济效益为特点,以便评估电网发展规模和速度、结构和安全性以及效率和效益,进而带动科技项... 为满足双碳背景下电网精准投资的迫切需求,面对目前电网科技项目数量的急剧增加,迫切需要构建一个后评价指标体系,以低碳绿色发展、运营效率和经济效益为特点,以便评估电网发展规模和速度、结构和安全性以及效率和效益,进而带动科技项目成果转化率的提高,加快科研项目向市场的推广进程。从组织管理、技术水平、成果应用以及影响力4个方面构建电网科技项目后评估的评价指标体系,应用三角模糊数和变异系数法结合的组合赋权法确定各评价指标的权重,基于PROMETHEE-Ⅱ方法对电网科技项目进行后评估,确定最终的评价结果。以实际案例分析,验证该模型具有可行性。 展开更多
关键词 科技项目 后评估 变异系数法 PROMETHEE-
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Microwave-Assisted Au and Ag Nanoparticle Synthesis: An Energy Phase-Space Projection Analysis
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 CAS 2023年第4期149-174,共26页
Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commerci... Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commercial temperature controlled microwave chemistry ovens (TCMC), digesters, and axial field helical antennae. For each of these microwave applicators the process energy budget where estimated (Watts multiplied by process time = kJ) and energy density (applied energy divided by suspension volume = kJ·ml<sup>-1</sup>) range between 180 ± 176.8 kJ, and 79.5 ± 79 kJ·ml<sup>-1</sup>, respectively. The axial field helical field an-tenna applicator is found to be the most energy efficient (0.253 kJ·m<sup>-1</sup> per kJ, at 36 W). Followed by microwave ovens (4.47 ± 3.9 kJ·ml<sup>-1</sup> per 76.83 ± 39 kJ), and TCMC ovens (2.86 ± 2.3 kJ·m<sup>-1</sup> per 343 ± 321.5 kJ). The digester applicators have the least energy efficiency (36.2 ± 50.7 kJ·m<sup>-1</sup> per 1010 ± 620 kJ). A comparison with reconstructed ‘non-thermal’ microwave oven inactivation microorganism experiments yields a power-law signature of n = 0.846 (R<sup>2</sup> = 0.7923) four orders of magnitude. The paper provides a discussion on the Au and Ag nanoparticle chemistry and bio-chemistry synthesis aspects of the microwave applicator energy datasets and variation within each dataset. The visual and analytical approach within the energy phase-space projection enables a nanoparticle synthesis route to be systematically characterized, and where changes to the synthesis are to be mapped and compared directly with historical datasets. In order to help identify lower cost nanoparticle synthesis, in addition to potentially reduce synthesis energy to routes informed changes to potentially reduce synthesis energy budget, along with nanoparticle morphology and yield. 展开更多
关键词 Turkevich Microwave-Assisted Synthesis Ag AU HYDROXYAPATITE Nanoparticle FUNCTIONALIZATION Energy phase-Space projection
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Self-reliance and Innovation of Qinshan Phase Ⅱ NPP Project
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作者 Ye Qizhen,Yang Lanhe(Nuclear Power Qinshan Joint Venture Company,Haiyan 314300,China) 《工程科学(英文版)》 2007年第4期20-35,共16页
This article mainly describes the self-reliance and innovation of Qinshan nuclear power project of phase II,in-between it contains new reactor core design,as well as related experimental and calculation analysis,espec... This article mainly describes the self-reliance and innovation of Qinshan nuclear power project of phase II,in-between it contains new reactor core design,as well as related experimental and calculation analysis,especially for new reactor design produced fluid-induced vibration model test,theoretical analysis and testing in-built reactor;aiming at two-loop NSSS a series improvement made for safety systems and related safety analysis to enhance their reliability and redundancy;according to specialty of two-loop NSSS an optimization made for NPP parameters and design of related equipments,for the purpose to make the output of NPP maximal;design of main reactor building and T-G building also improved according to characteristics of two-loop NSSS and site conditions.CRDM and refueling machine are researched and manufactured on base of self-reliance,their performance are better than design requirements,large portion of key equipments are localized through different way.In construction first time realized the integrated erection of containment dome.During the commissioning non-nuclear steam driving of T-G set,as well as 500 kV high voltage rising using emergent diesel generator,etc.are carried out.In period of operation still continuous innovation and improvement are made,so that to keep the good record of operation. 展开更多
关键词 NUCLEAR POWER project phase
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基于改进NSGA-Ⅱ的交叉口信号配时多目标优化
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作者 陈秀锋 王瑞聪 +2 位作者 陈咨羽 高梦圆 郭玉彤 《青岛理工大学学报》 CAS 2024年第1期111-117,125,共8页
针对城市交叉口信号配时多目标优化的求解效率问题,设计了一种基于改进NSGA-Ⅱ的城市交叉口信号配时优化方案。该方法采纳车辆延误、停车次数、通行能力3个评价指标设计了多目标信号配时优化模型,并提出了改进的NSGA-Ⅱ(NSGA-Ⅱ-DE)对... 针对城市交叉口信号配时多目标优化的求解效率问题,设计了一种基于改进NSGA-Ⅱ的城市交叉口信号配时优化方案。该方法采纳车辆延误、停车次数、通行能力3个评价指标设计了多目标信号配时优化模型,并提出了改进的NSGA-Ⅱ(NSGA-Ⅱ-DE)对配时模型进行求解。NSGA-Ⅱ-DE采用DE/Rand/1的全局变异策略对NSGA-Ⅱ算法选择策略进行改进,并设计了种群动态更新算法,提高了算法的收敛速度和求解精度。结果表明改进算法获得了较好的Pareto最优解,通过典型交叉口仿真验证,相对于NSGA-Ⅱ算法,NSGA-Ⅱ-DE方法设计配时方案平均车辆延误优化提升13.42%,排队长度优化提升16.73%,平均停车次数优化提升15.50%,能够实现城市交叉口的最优化控制。 展开更多
关键词 交通工程 信号配时 多目标优化 T形交叉口 城市交通 相位 NSGA--DE算法 全局变异
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强组合PhaseⅠ-PhaseⅡ次可行方向法 被引量:7
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作者 简金宝 《经济数学》 1995年第1期64-70,共7页
本文对Polak等人的组合NaseⅠ-Ⅱ可行方向法进行改进,使之不仅能自动地将初始化阶段(Phasel)和最优化阶段(PhaseⅡ)统一起来,而且保证了满足不等式约束的函数个数不断叠累递增,故称改进后的算法为强组合P... 本文对Polak等人的组合NaseⅠ-Ⅱ可行方向法进行改进,使之不仅能自动地将初始化阶段(Phasel)和最优化阶段(PhaseⅡ)统一起来,而且保证了满足不等式约束的函数个数不断叠累递增,故称改进后的算法为强组合PhaseⅠ-ⅡPhaseⅡ次可行方向法.本文算法包含了一种新的目标局数非单词的非精确线搜索,它保证了算法产生的点列的任何聚点都是问题的K-T的点. 展开更多
关键词 非线性规划 强组合phaseⅠ-phase 可行方向法 非单调线搜索 整体收敛性
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Low side lobe pattern synthesis using projection method with genetic algorithm for truncated cone conformal phased arrays 被引量:7
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作者 Guoqi Zeng Siyin Li +1 位作者 Yan Zhang Shanwei L 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期554-559,共6页
A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone con... A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone conformal phased arrays are projected to the tangent plane in one generatrix of the truncated cone. Then two dimensional (2D) Chebyshev amplitude distribution optimization is respectively used in two mutual vertical directions of the tangent plane. According to the location of the elements, the excitation current amplitude distribution of each element on the conformal structure is derived reversely, then the excitation current amplitude is further optimized by using the genetic algorithm (GA). A truncated cone problem with 8x8 elements on it, and a 3D pattern desired side lobe level (SLL) up to 35 dB, is studied. By using the hybrid method, the optimal goal is accomplished with acceptable CPU time, which indicates that this hybrid method for the low sidelobe synthesis is feasible. 展开更多
关键词 conformal phased array low side lobe pattern synthe-sis projection method genetic algorithm optimization.
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Phase Ⅱ open-label study of recombinant circularly permuted TRAIL as a single-agent treatment for relapsed or refractory multiple myeloma 被引量:5
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作者 Yun Leng Lugui Qiu +7 位作者 Jian Hou Yaozhong Zhao Xuejun Zhang Shifang Yang Hao Xi Zhongxia Huang Ling Pan Wenming Chen 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第12期699-705,共7页
Background: Despite the recent development of new therapies, multiple myeloma(MM) remains an incurable disease. Thus, new, efective treatments are urgently needed, particularly for relapsed or refractory MM(RRMM). In ... Background: Despite the recent development of new therapies, multiple myeloma(MM) remains an incurable disease. Thus, new, efective treatments are urgently needed, particularly for relapsed or refractory MM(RRMM). In an earlier phase I study, a novel form of recombinant human Apo2L/tumor necrosis factor-related apoptosis-inducing ligand(TRAIL) that is currently in clinical development for the treatment of hematologic malignancies, i.e., circularly permuted TRAIL(CPT), was well tolerated at a dose of 2.5 mg/kg per day and showed promising preliminary activity in patients with RRMM. This phase II, open-label, multicenter study further investigated the eicacy and safety of 2.5-mg/kg per day CPT as single-agent therapy for patients with RRMM.Methods: Patients with RRMM were treated once daily with CPT(2.5 mg/kg, intravenously) for 14 consecutive days for each 21-day cycle. Clinical response and toxicity were assessed after each treatment cycle.Results: Twenty-seven patients received CPT. Using the European Group for Blood and Marrow Transplantation criteria, we calculated the overall response rate of 33.3% with 1 near-complete response(n CR) and 8 partial responses(PRs). The clinical beneit rate(48.1%) included 1 nCR, 8 PRs, and 4 minimal responses. The most common treatmentrelated adverse events(TRAEs) were fever, aspartate aminotransferase elevation, alanine aminotransferase elevation, leucopenia, rash, neutropenia, and thrombocytopenia. We graded toxicity using the Common Toxicity Criteria for Adverse Events, version 3.0, and determined that 37.0% of patients had at least 1 grade 3–4 TRAE.Conclusions: CPT as a single agent can elicit a response in patients with RRMM and is well tolerated. Further clinical investigation is warranted. 展开更多
关键词 Recombinant human circularly permuted TRAIL phase trial Relapsed or refractory multiple myeloma Efficacy Safety
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基于改进NSGA-Ⅱ的铁路项目进度计划多目标优化
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作者 周国华 马依婷 《工业工程》 北大核心 2023年第4期85-95,共11页
以总工期最短和总费用最低为目标,针对包含线性活动、条状活动、块状活动等多种施工场景的铁路工程项目,基于RSM方法构建铁路项目多目标优化模型,并提出一种改进的NSGA-Ⅱ算法对模型进行求解.算法设计一种分层次选取种群个体的均匀进化... 以总工期最短和总费用最低为目标,针对包含线性活动、条状活动、块状活动等多种施工场景的铁路工程项目,基于RSM方法构建铁路项目多目标优化模型,并提出一种改进的NSGA-Ⅱ算法对模型进行求解.算法设计一种分层次选取种群个体的均匀进化精英选择策略,以提高种群多样性和收敛性;同时引入差分进化算法的变异、交叉算子,构造分层多策略自适应变异、交叉算子,以平衡整个种群的局部搜索能力和全局搜索能力.结果表明,增加对特殊活动和施工方向的考虑,可增强模型对铁路项目的适用性;改进后的算法收敛速度快,运行稳定,得到的结果更优,能够满足较大规模铁路项目进度计划优化. 展开更多
关键词 重复性项目调度 NSGA-算法 工期-费用 多目标优化
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DEFORMATION MEASUREMENT USING DUAL-FREQUENCY PROJECTION GRATING PHASE-SHIFT PROFILOMETRY 被引量:2
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作者 Yanming Chen Yuming He Eryi Hu Hongmao Zhu 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第2期110-115,共6页
2π phase ambiguity problem is very important in phase measurement when a deformed object has a large out of plane displacement. The dual-frequency projection grating phaseshifting profilometry (PSP) can be used to ... 2π phase ambiguity problem is very important in phase measurement when a deformed object has a large out of plane displacement. The dual-frequency projection grating phaseshifting profilometry (PSP) can be used to solve such an issue. In the measurement, two properchosen frequency gratings are utilized to synthesize an equivalent wavelength grating which ensures the computed phase in a principal phase range. Thus, the error caused by the phase unwrapping process with the conventional phase reconstruct algorithm can be eliminated. Finally, experimental result of a specimen with large plastic deformation is given to prove that the proposed method is effective to handle the phase discontinuity. 展开更多
关键词 dual-frequency phase-shift profilometry projection grating phase unwrapping DEFORMATION
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Multicenter phase Ⅱ trial of modified FOLFIRINOX in gemcitabine-refractory pancreatic cancer 被引量:3
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作者 Moon Jae Chung Huapyong Kang +8 位作者 Ho Gak Kim Jong Jin Hyun Jun Kyu Lee Kwang Hyuck Lee Myung Hwan Noh Dae Hwan Kang Sang Hyub Lee Seungmin Bang 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2018年第12期505-515,共11页
AIM To evaluate the efficacy and safety of modified FOLFIRINOX as a second-line treatment for gemcitabine(GEM)-refractory unresectable pancreatic cancer(PC).METHODS This study was a prospective, multicenter, one-arm, ... AIM To evaluate the efficacy and safety of modified FOLFIRINOX as a second-line treatment for gemcitabine(GEM)-refractory unresectable pancreatic cancer(PC).METHODS This study was a prospective, multicenter, one-arm, open-label, phase Ⅱ trial. Patients with unresectable PC, who showed disease progression during GEMbased chemotherapy were enrolled. All patients were administered FOLFIRINOX with reduced irinotecan and oxaliplatin(RIO; irinotecan 120 mg/m^2 and oxaliplatin 60 mg/m^2), which was set according to the phase Ⅰ study of FOLFIRINOX. The objective response rate(ORR), disease control rate(DCR), progressionfree survival(PFS), overall survival(OS), adverse events were evaluated. Additionally, changes in quality of life(QoL) were assessed using a questionnaire on QoL.RESULTS Between August 2015 and May 2016, a total of 48 patients were enrolled. The median follow-up time was 259 d with a median of 8.5 cycles. The ORR and DCR were 18.8% and 62.5%, respectively, including one patient who showed complete remission. The median PFS was 5.8 mo [95% confidence interval(CI): 3.7-7.9] and median OS was 9.0 mo(95%CI: 6.4-11.6). Neutropenia(64.6%) was the most common grade 3-4 adverse event, followed by febrile neutropenia(16.7%). Although 14.6% of patients experienced grade 3 fatigue, most non-hematologic AEs were under grade 2. In the QoL analysis, the global health status score before treatment was not different from the score at the last visit after treatment(45.43 ± 22.88 vs 48.66 ± 24.14, P = 0.548).CONCLUSION FOLFIRINOX with RIO showed acceptable toxicity and promising efficacy for GEM-refractory unresectable PC. However, this treatment requires careful observation of treatment-related hematologic toxicities. 展开更多
关键词 Pancreatic cancer FOLFIRINOX Clinical Trial phase Chemotherapy GEMCITABINE REFRACTORY
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Phase Transfer Research for Heteropolyanions Containing Cr(Ⅲ),Mn(Ⅳ),Co(Ⅱ),Zn(Ⅱ) 被引量:1
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作者 ZHANG Shu-yun HUANG Ru-dan +1 位作者 YU Xin-wu LI Baitao and WANG En-bo(Departnient of Chemistry,Northeast Normal University,Changchun,130024) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1996年第4期397-400,共4页
PhaseTransferResearchforHeteropolyanionsContainingCr(Ⅲ),Mn(Ⅳ),Co(Ⅱ),Zn(Ⅱ)ZHANGShu-yun;HUANGRu-dan;YUXin-wu;L... PhaseTransferResearchforHeteropolyanionsContainingCr(Ⅲ),Mn(Ⅳ),Co(Ⅱ),Zn(Ⅱ)ZHANGShu-yun;HUANGRu-dan;YUXin-wu;LIBaitaoandWANGEn-... 展开更多
关键词 s:Heteropolyanions phase transfer Cr(Ⅲ) Mn(Ⅳ) Co() Zn()
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Total synthesis of human urotension-Ⅱ by microwave-assisted solid phase method 被引量:1
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作者 Hui Bin Zhang Yu Shi Chi Wen Long Huang Shuai Jian Ni 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期902-904,共3页
Human urotension-Ⅱ was synthesized efficiently on Wang resin under microwave irradiation using Fmoc/tBu orthogonal protection strategy. Disulphide bridge was formed on solid phase with the irradiation of microwave, t... Human urotension-Ⅱ was synthesized efficiently on Wang resin under microwave irradiation using Fmoc/tBu orthogonal protection strategy. Disulphide bridge was formed on solid phase with the irradiation of microwave, then the whole peptide was cleaved from the resin. The purity of crude peptide cyclized under microwave irradiation was higher than that under room temperature. 展开更多
关键词 Human urotension- Microwave irradiation Solid phase Disulphide bridge
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Project2000在模具MRPⅡ中的应用
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作者 刘斌 曹咏 《现代计算机》 2001年第8期76-78,共3页
Project2000是微软公司推出的一种功能强大而灵活的项目管理工具,可以用于控制简单或复杂的项目。模具MRPⅡ是针对模具行业特点开发的MRPⅡ系统,在其生产管理子系统中,适合于引入Project2000这一项目管理工具。本文讨论了如何有机地把Pr... Project2000是微软公司推出的一种功能强大而灵活的项目管理工具,可以用于控制简单或复杂的项目。模具MRPⅡ是针对模具行业特点开发的MRPⅡ系统,在其生产管理子系统中,适合于引入Project2000这一项目管理工具。本文讨论了如何有机地把Project2000与模具MRPⅡ系统相结合,探讨了Project2000的数据库结构,并实现了与MRPⅡ系统数据库的有效互连。 展开更多
关键词 模具 MRP project2000 项目管理软件
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PHASE Ⅱ STUDY OF GEMCITABINE COMBINED WITH PLATINUM CHEMOTHERAPY FOR RECURRENT EPITHELIAL OVARIAN CANCER 被引量:1
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作者 Peng Peng Keng Shen Jia-xin Yang Ming Wu Hui-fang Huang Ling-ya Pan Jing-he Lang 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第3期177-182,共6页
Objective To evaluate the anti-tumor effect and toxicity of gemcitabine combined with platinum chemotherapy on recurrent epithelial ovarian cancer. Methods Phase Ⅱstudy of gemcitabine combined with platinum chemother... Objective To evaluate the anti-tumor effect and toxicity of gemcitabine combined with platinum chemotherapy on recurrent epithelial ovarian cancer. Methods Phase Ⅱstudy of gemcitabine combined with platinum chemotherapy was carried out in 22 patients with recurrent epithelial ovarian cancer. Median age of patients was 50.5 years old. Seven patients were platinum-sensitive and 15 patients were platinum-resistant or -refractory. All patients received gemcitabine combined with carboplatin or oxaliplatin chemotherapy. Patients' response rate (RR) and toxicity of gemcitabine combined with platinum chemotherapy were evaluated. Results A total of 98 gemcitabine-based chemotherapy cycles were performed. Total RR was 36.4%, RR of platinum-sensitive patients was 4/7 and platinum-resistant and -refractory patients was 4/15. The estimated median survival time was 10.0 months (95%CI: 7.0-13.0) after initiation of gemcitabine combined with platinum chemotherapy. There was no significant difference in survival time between platinum-resistant/refractory group and platinum-sensitive group (P=0.061). Side effects of gemcitabine combined with platinum chemotherapy were observed in 81.8% of patients. Grade Ⅱ/Ⅲ anemia (54.5%) and grade Ⅲ/Ⅳ neutropenia (54.5%) were most common toxicities. Ten (45.5%) patients had to delay their chemotherapy cycles or reduce the dose of chemotherapeutic drugs because of the severe side effects. Fourteen (63.6%) patients received granulocyte colony-stimulating factor to relieve neutropenia, and 8 (36.4%) patients received component blood transfusion to treat anemia or thrombocytopenia. There was no treatment-associated death. Conclusion Gemcitabine combined with platinum chemotherapy appears to be an effective and well-tolerant treatment for recurrent epithelial ovarian cancer, including platinum-resistant or -refractory diseases. 展开更多
关键词 卵巢癌 化学疗法 临床检查 病理机制
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Project Construction and Important Technical Innovation for Qinshan Phase Ⅲ (PHWR) Nuclear Power Plant 被引量:1
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作者 Third Qinshan Nuclear Power Co.Ltd,CNNC(Haiyan County,Zhejiang Province,314300,China) 《工程科学(英文版)》 2007年第4期98-117,134,共21页
Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant,the first commercial heavy water reactor nuclear power plant in China,was the biggest trade project performed between the governments of China and Canada.As the owner,the Thir... Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant,the first commercial heavy water reactor nuclear power plant in China,was the biggest trade project performed between the governments of China and Canada.As the owner,the Third Qinshan Nuclear Power Company(TQNPC)persisted in independent innovation management during the project construction,commissioning and self-dependent operation,efficiently realizing the three controls of the project,i.e.quality control,schedule control and investment control,and persisted in technical improvement on the basis of digestion and absorption of CANDU-6 technology to improve the unit safety and reliability.The project construction practice has helped China's nuclear power project management to becomeprogrammed,computerized,standardized and internationalized management from the existing basis.After completion of the project,with unit safe and steady operation as the prerequisite,TQNPC performed several technical modifications and innovations to continuously improve the unit performance.In the area of staff development,TQNPC paid much attention to cultivation of corporate culture,strengthed staff training and built up a good circulating mechanism with staff training and project construction promoting each other.Further to "Zero Breakthrough" and a new step forward of locolization successfully realized in Qinshan Nuclear Power Plant and Nuclear Power Qinshan Joint Venture Company,the improvement and developemnt of nuclear power project management level in Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant provided reference for promotion of nuclear power development in China and standardized management of introducing large imported project. 展开更多
关键词 Qinshan phase HEAVY Water REACTOR NUCLEAR power plant project construction TECHNICAL INNOVATION
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Quality Guided Phase Unwrapping for Fringe Projection Profilometry 被引量:1
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作者 C.J.Tay 《实验力学》 CSCD 北大核心 2006年第1期71-76,共6页
Fringe projection technique is a non-contact, full field 3-D shape measurement method. The object depth information is recorded in one or several deformed fringe patterns. The phase-shifting algorithm or the Fourier t... Fringe projection technique is a non-contact, full field 3-D shape measurement method. The object depth information is recorded in one or several deformed fringe patterns. The phase-shifting algorithm or the Fourier transform method can be used to extract the wrapped phase data. A phase unwrapping process is then applied to retrieve a continuous phase distribution, which represents the surface profile of the test object. In this paper, a quality-guided phase unwrapping approach is incorporated and two novel phase quality evaluation methods are proposed to facilitate the phase unwrapping process. 展开更多
关键词 相品质 相展开 边缘发射 相移 傅立叶变换
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A consistent projection-based SUPG/PSPG XFEM for incompressible two-phase flows 被引量:2
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作者 Jian-Hui Liao Zhuo Zhuang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第5期1309-1322,共14页
In this paper, a consistent projection-based streamline upwind/pressure stabilizing Petrov-Galerkin (SUPG/PSPG) extended finite element method (XFEM) is presented to model incompressible immiscible two-phase flows... In this paper, a consistent projection-based streamline upwind/pressure stabilizing Petrov-Galerkin (SUPG/PSPG) extended finite element method (XFEM) is presented to model incompressible immiscible two-phase flows. As the application of linear elements in SUPG/PSPG schemes gives rise to inconsistency in stabilization terms due to the inability to regenerate the diffusive term from viscous stresses, the numerical accuracy would deteriorate dramatically. To address this issue, projections of convection and pressure gradient terms are constructed and incorporated into the stabilization formulation in our method. This would substantially recover the consistency and free the practitioner from burdensome computations of most items in the residual. Moreover, the XFEM is employed to consider in a convenient way the fluid properties that have interfacial jumps leading to discontinuities in the velocity and pressure fields as well as the projections. A number of numerical examples are analyzed to demonstrate the complete recovery of consistency, the reproduction of interfacial discontinuities and the ability of the proposed projection-based SUPG/PSPG XFEM to model two-phase flows with open and closed interfaces. 展开更多
关键词 Two-phase flow XFEM SUPG/PSPG algorithm Consistency Discontinuous projection
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Risk Assessment at the Design Phase of Construction Projects in Ghana
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作者 Maurice Azochiman Awuni 《Journal of Building Construction and Planning Research》 2019年第2期39-58,共20页
The study was carried out exclusively in Ghana to explore the approaches employed by consultants in risk assessment at the design phase of projects in Ghana. One hundred and fourteen (114) consultants were selected ou... The study was carried out exclusively in Ghana to explore the approaches employed by consultants in risk assessment at the design phase of projects in Ghana. One hundred and fourteen (114) consultants were selected out of a population of one hundred and eighty six (186) from three main professional associations in Ghana made up of the Ghana Institute of Architects, Ghana Institution of Engineers and the Ghana Institution of Surveyors (Quantity Surveying Division) practicing in Ghana for the study. Both primary and secondary data were collected. A descriptive survey was also used to observe and describe the presence, frequency or absence of characteristics of a phenomenon as it naturally occurred, in order to gain additional information. A questionnaire was also designed to collect data from the architects, engineers and quantity surveyors. The data was analyzed using Statistical Package for the Social Scientists (SPSS) 17.0. Descriptive and inferential statistics, such as frequency tables, percentages and cross tabulations were used in the data analysis and summaries. Simple tests of associations were undertaken by using Chi square and Cramer’s V statistics to compare relationships between variables. Again, relative importance index was also used to analyze some of the data by computing to deduce their rankings. The relative importance index was used to analyze some of the data by computing to deduce their rankings. The research revealed that majority of consultants had an average knowledge of risk management. Based on the findings it was recommended that consultants undergo advanced training in risk assessment. It was therefore suggested that consultancy firms should develop a set of laid down procedures for consultants to use in risk assessment in order that the use of intuition employed by majority is lessened. The challenges observed in risk assessment and the remedial steps suggested curtailing the detrimental effects of risks would be of wide importance to many developing economies. 展开更多
关键词 Construction INDUSTRY project RISK Management Assessment DESIGN phase
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Profilometry with Grating Projection Based on One-step Phase Shift 被引量:1
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作者 FAN Yun zheng (School of Physics and Microelectronics, Shandong University, Jinan 250061, CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第3期189-192,共4页
An optical technique for 3 D shape measurement is presented. This technique, based on a deformed projected grating pattern which carries 3 D information of the measured object, can automatically and accurately obtain ... An optical technique for 3 D shape measurement is presented. This technique, based on a deformed projected grating pattern which carries 3 D information of the measured object, can automatically and accurately obtain the phase map of a measured object by using one step phase shift algorithm.In comparison with traditional phase shift technique, the technique is much faster, with the equivalent accuracy. Only one frame image is sufficient for measuring. Experimental result of typical object is presented. 展开更多
关键词 三维表面轮廓 相移 表面光度测定法 光栅投影
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Velocity Projection with Upwind Scheme Based on the Discontinuous Galerkin Methods for the Two Phase Flow Problem
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作者 Jiangyong Hou Wenjing Yan Jie Chen 《International Journal of Modern Nonlinear Theory and Application》 2015年第2期127-141,共15页
The upwind scheme is very important in the numerical approximation of some problems such as the convection dominated problem, the two-phase flow problem, and so on. For the fractional flow formulation of the two-phase... The upwind scheme is very important in the numerical approximation of some problems such as the convection dominated problem, the two-phase flow problem, and so on. For the fractional flow formulation of the two-phase flow problem, the Penalty Discontinuous Galerkin (PDG) methods combined with the upwind scheme are usually used to solve the phase pressure equation. In this case, unless the upwind scheme is taken into consideration in the velocity reconstruction, the local mass balance cannot hold exactly. In this paper, we present a scheme of velocity reconstruction in some H(div) spaces with considering the upwind scheme totally. Furthermore, the different ways to calculate the nonlinear coefficients may have distinct and significant effects, which have been investigated by some authors. We propose a new algorithm to obtain a more effective and stable approximation of the coefficients under the consideration of the upwind scheme. 展开更多
关键词 VELOCITY projectION UPWIND Scheme PENALTY DISCONTINUOUS GALERKIN Methods Two phase Flow in Porous Media
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