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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries
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作者 Haining Yin Zhaoxiang Wang +3 位作者 Lin Wang Jianhong Cao Jiakui Wang Zhumei Xi 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期713-731,共19页
Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with ... Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards. 展开更多
关键词 Vitis vinifera L. Orientated rows Berry composition SUGAR PHENOLIC Light quality Solar radiation
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Inter-Row Spacing of PV Power Plant
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作者 Laiqat Ali Khan 《Energy and Power Engineering》 2024年第3期121-129,共9页
When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designe... When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designed. This research paper and case study will help a lot to avoid shadow, especially when selecting inter-row spacing between the strings of solar power plants. 展开更多
关键词 Inter row Spacing Shadow Effect on PV Plant Hot Spot Heating
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堆石体修正Rowe剪胀方程与南水模型 被引量:43
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作者 张丙印 贾延安 张宗亮 《岩土工程学报》 EI CAS CSCD 北大核心 2007年第10期1443-1448,共6页
在分析堆石体三轴试验成果的基础上,探讨了堆石体的体积变形特性,提出了形式简洁的堆石体修正Rowe剪胀方程。将所建立的修正Rowe剪胀方程引入到沈珠江院士提出的"南水模型",克服了该模型由于采用体变–轴向应变抛物线假设所... 在分析堆石体三轴试验成果的基础上,探讨了堆石体的体积变形特性,提出了形式简洁的堆石体修正Rowe剪胀方程。将所建立的修正Rowe剪胀方程引入到沈珠江院士提出的"南水模型",克服了该模型由于采用体变–轴向应变抛物线假设所带来的一些缺陷。应用堆石体常规三轴试验和典型复杂应力路径三轴试验成果对修正后模型的合理性进行了验证。 展开更多
关键词 堆石料 rowe剪胀方程 双屈服面弹塑性模型
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敏感环境下地下水池基坑围护施工技术
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作者 苏宇 《山西建筑》 2025年第2期68-71,81,共5页
杨树浦水厂深度处理改造工程具有地质条件复杂、场地工况敏感、施工组织及环境保护要求高等特点。结合周边建筑物密集,且离运营中的文保工业建筑最近距离仅为15 m的特点,从支撑选型、回填及降水、土方开挖等方面介绍了敏感环境下地下水... 杨树浦水厂深度处理改造工程具有地质条件复杂、场地工况敏感、施工组织及环境保护要求高等特点。结合周边建筑物密集,且离运营中的文保工业建筑最近距离仅为15 m的特点,从支撑选型、回填及降水、土方开挖等方面介绍了敏感环境下地下水池处理改造基坑围护施工技术,有效地保障了重大工程的高效、安全实施,为今后类似环境下地下结构建造涉及到的基坑施工提供了借鉴和参考。 展开更多
关键词 硬咬合排桩 复杂地质 文保建筑 双C环形支撑 基坑开挖 工期高效
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Effects of Ratio of Row Spacing to Intrarow Spacing on Yield and Top Three Leaves of Super High-yielding Early and Late Rice 被引量:2
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作者 林洪鑫 彭春瑞 +5 位作者 雷享亮 袁展汽 肖运萍 刘仁根 胡启锋 张结刚 《Agricultural Science & Technology》 CAS 2014年第1期52-56,101,共6页
Using a split plot design, super high-yielding early rice &quot;Zhongjiazao 17&quot;and &quot;Ganxin 203&quot; and super high-yielding late rice &quot;Ganxin 688&quot; and &quot;Wufengy-ouT025&quot; were taken... Using a split plot design, super high-yielding early rice &quot;Zhongjiazao 17&quot;and &quot;Ganxin 203&quot; and super high-yielding late rice &quot;Ganxin 688&quot; and &quot;Wufengy-ouT025&quot; were taken as materials with planting density the same at 312 000 hil s/hm2, to explore the effects of RS/IS (Ratio of row spacing to intrarow row spacing) on yield, top three leaves morphological features and its relationship of them in 2011 and 2012. The results showed that, whether early or late rice, biomass, accumula-tion and apparent utilizing rate of nitrogen were lower in RS/IS5.0 (40.0 cm &#215;8.0 cm) treatment, but yield of rice was higher in RS/IS2.0 (25.0 cm &#215;12.8 cm) treatment;grain numbers per spike of rice was more in RS/IS2.8 (30.0 cm&#215;10.7 cm) treatment, and thousand-grain weight of rice was higher in RS/IS1.3 (20.0 cm&#215;16.0 cm) treat-ment. For 4 varieties of early or late rice aforementioned, basal angle, opening an-gle and leaf area of 2nd leaf from top were larger in RS/IS5.0 treatment, and basal angle and opening angle were smal er in RS/IS2.0 treatment and leaf area smal er in RS/IS1.3 treatment. 展开更多
关键词 Super high-yielding early and late rice Ratio of row spacing to intrarowspacing Top three leaves Leaf morphology
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Bell不等式实验检验的重大进展——Weihs实验和Rowe实验述评 被引量:1
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作者 黄政新 《南京理工大学学报(社会科学版)》 2010年第4期45-50,共6页
Weihs实验(1998)和Rowe实验(2001)可能是自Aspect实验(1982)以来已完成的几十个Bell型实验中最重要的两个。这两个实验已分别地封闭了定域性漏洞和效率漏洞,但定域隐变量理论并没有完全被排除。相信有朝一日人们会完成一个无漏洞的实验... Weihs实验(1998)和Rowe实验(2001)可能是自Aspect实验(1982)以来已完成的几十个Bell型实验中最重要的两个。这两个实验已分别地封闭了定域性漏洞和效率漏洞,但定域隐变量理论并没有完全被排除。相信有朝一日人们会完成一个无漏洞的实验。即使如此,定域隐变量理被排除的问题仍然会是悬而未决的。断言试图通过完成一个无争议的判决性实验来解决定域隐变量理论与量子力学的冲突是不可能的。 展开更多
关键词 Weihs实验 rowe实验 BELL不等式 定域性漏洞 效率漏洞
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Row Fixation - A Parallel Algorithm for Matrix Computing
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作者 沈文枫 郁松年 徐炜民 《Advances in Manufacturing》 SCIE CAS 2000年第S1期119-122,共4页
Row fixation is a parallel algorithm based on MPI that can be implemented on high performance computer system. It keeps the characteristics of matrices since row-computations are fixed on different nodes. Therefore t... Row fixation is a parallel algorithm based on MPI that can be implemented on high performance computer system. It keeps the characteristics of matrices since row-computations are fixed on different nodes. Therefore the locality of computation is realized effectively and the acceleration ratio is obtained very well for large scale parallel computations such as solving linear equations using Gaussian reduction method, LU decomposition of matrices and m-th power of matrices. 展开更多
关键词 row fixation MPI SMP augmented matrix speedup ratio
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Effects of Planting Density and Row Spacing on Grass Yield of Forage Sweet Sorghum(Sorghum bicolor [L.]Moench)
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作者 周汉章 刘环 +4 位作者 贾海燕 魏志敏 袁淑红 侯升林 李顺国 《Agricultural Science & Technology》 CAS 2017年第12期2345-2353,2371,共10页
[Objective] The aim was to explore high-yielding cultivation techniques for forage sweet sorghum. [Method[ The effects of planting density and row spacing on plant productivity and grass yield of forage sweet sorghum ... [Objective] The aim was to explore high-yielding cultivation techniques for forage sweet sorghum. [Method[ The effects of planting density and row spacing on plant productivity and grass yield of forage sweet sorghum (Sorghum bicolor (L.) Moench) were compared using split-plot design and LSD method of IBMSPSSStatis- ticsv22. [Result]The planting density and row spacing had important influence on the plant productivity and yield of forage sweet sorghum. The optimum planting density- row spacing combination for plant productivity of forage sweet sorghum was A1B,, i. e., planting density of 75 000 plants/hm2 and row spacing of 40 cm, and the opti- mum combination for yield of forage sweet sorghum was A2B,, i.e., planting density of 225 000 plants/hm2 and row spacing of 40 cm. [Conclusion] This study will pro- vide theoretical basis and technical support for the production practice of forage sweet sorghum. 展开更多
关键词 Forage sweet sorghum Planting density row spacing Grass yield
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Light Simplified Cultivation Techniques of Wide Row and Double Ridge with Filming, Fertilizing and Sowing on One for Foxtail Millet
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作者 夏雪岩 刘猛 +6 位作者 杜钟 宋世佳 赵宇 刘斐 任晓利 南春梅 李顺国 《Agricultural Science & Technology》 CAS 2016年第3期563-565,共3页
In view of the problems of completely depending on rain, low and unstable yield and complicated planting of dry land foxtail millet, the light simplified cultivation techniques of wide row and double ridge with filmin... In view of the problems of completely depending on rain, low and unstable yield and complicated planting of dry land foxtail millet, the light simplified cultivation techniques of wide row and double ridge with filming, fertilizing and sowing on one for foxtail millet was formed through the integration of plastic film mulching technology and mechanized production technology by Institute of Millet crops of Hebei Academy of Agriculture and Forestry Sciences, and the techniques were introduced from the key technologies of pre-sowing preparation, sowing, supporting equipment, field management, harvesting, plastic film recycling. 展开更多
关键词 Foxtail millet Wide row and double ridge cultivation Filming and fertilizing Light simplified cultivation techniques
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朝永-Rowe理论作为原子核代数模型的基础
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作者 周孝谦 《核技术》 CAS CSCD 北大核心 1989年第8期494-497,共4页
将Rowe的Sp(6)核集体运动模型以两种方法嵌入较大的李代数。分别以费米子和玻色子为基础。两种方法得到的大的李代数都有丰富的约化群链。它们分别与FDSM和IBM相应。
关键词 原子核 代数模型 rowe理论 约化群
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关节镜下单排固定与无结缝线桥固定治疗合并骨质疏松的肩袖损伤
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作者 张浩亮 夏思佳 +3 位作者 展兵振 冯硕 查国春 李程 《中国组织工程研究》 CAS 北大核心 2025年第15期3188-3192,共5页
背景:关节镜下单排固定与无结缝线桥固定技术已普遍应用于治疗肩袖损伤,但对于合并骨质疏松的肩袖损伤的修复效果尚不明确。目的:探讨关节镜下单排固定与无结缝线桥固定治疗合并骨质疏松的肩袖损伤的临床疗效。方法:回顾性分析2018年1月... 背景:关节镜下单排固定与无结缝线桥固定技术已普遍应用于治疗肩袖损伤,但对于合并骨质疏松的肩袖损伤的修复效果尚不明确。目的:探讨关节镜下单排固定与无结缝线桥固定治疗合并骨质疏松的肩袖损伤的临床疗效。方法:回顾性分析2018年1月至2022年8月徐州医科大学附属医院收治的122例接受关节镜治疗的合并骨质疏松的肩袖损伤患者,根据治疗方案分为2组,其中单排固定患者63例(单排组),无结缝线桥固定患者59例(缝线桥组)。比较两组患者术前和术后1年时的疼痛目测类比评分、美国加州大学肩关节评分、美国肩肘外科医师学会评分、Constant-Murley肩关节功能评分和肩关节活动度;术后1年采用Sugaya分型标准评估肩袖再撕裂情况;记录两组患者并发症发生情况。结果与结论:①所有患者均获得1年以上随访;术后两组患者均未发生切口感染、神经损伤等并发症;②两组患者术后1年目测类比评分、美国加州大学肩关节评分、美国肩肘外科医师学会评分、Constant-Murley评分以及肩关节活动度均较术前显著改善(P<0.05);缝线桥组术后1年目测类比评分、美国加州大学肩关节评分、美国肩肘外科医师学会评分、Constant-Murley评分以及肩关节活动度均优于单排组(P<0.05);③术后1年,单排组再撕裂率为22%(14/63),显著高于缝线桥组7%(4/59),差异有显著性意义(χ^(2)=5.777,P=0.016);④提示关节镜下单排固定与无结缝线桥固定治疗合并骨质疏松的肩袖损伤均能获得满意的临床疗效,但无结缝线桥固定修复效果更好,术后再撕裂率更低。 展开更多
关键词 肩袖损伤 单排固定 无结缝线桥技术 骨质疏松 关节镜
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ORA_ROWSCN伪列在Oracle历史数据迁移中的应用研究
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作者 徐鲁辉 吕丽平 《现代计算机》 2012年第15期58-60,共3页
通过对Oracle常见数据迁移方法的利弊分析,给出利用ORA_ROWSCN行级跟踪模式的Oralce 10g数据迁移解决方案,该方案既使数据迁移省时省力,又能保证数据库的完整性和一致性,为企业做Oracle历史数据迁移提供完美方案。
关键词 ORACLE 数据迁移 OR-A rowSCN伪列 行级跟踪
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Mapping of Mutant Gene prbs Controlling Poly-Row-and-Branched Spike in Barley (Hordeum vulgare L.) 被引量:6
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作者 HUANG Bi-guang WU Wei-ren 《Agricultural Sciences in China》 CAS CSCD 2011年第10期1501-1505,共5页
A row-type mutant of barley named poly-row-and-branched spike (prbs) was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produce... A row-type mutant of barley named poly-row-and-branched spike (prbs) was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produces branched spikes with irregular multiple rows. Genetic analysis indicated that the mutant phenotype was caused by a recessive gene prbs, and the PRBS locus had a recessive epistatic effect on an independent locus (denoted as Vrsx) conferring the variation of two-rowed spike vs. six-rowed spike. This study aimed to map PRBS as well as Vrsx using simple sequence repeats (SSR) markers. We developed an F2 population from a cross between the prbs mutant and a six-rowed cultivar Putianwudu for the gene mapping. As the two target loci interacted to result in a segregation ratio of two-rowed type:six-rowed type:prbs=9:3:4 in the population, we adopted a special strategy to map the two loci. PRBS was mapped between SSR markers HvLTPPB and Bmag0508A on the short arm of chromosome 3H, with distances of 24.7 and 14.3 cM to the two markers, respectively. Vrsx was mapped between SSR markers Bmag0125 and Bmag0378 on chromosome 2H, with distances of 6.9 and 15.3 cM to the two markers, respectively. This suggests that Vrsx should be the known locus Vrs1, which predominantly controls row-type variation in barley cultivars, and PRBS is a new locus related to the row type of spikes in barley. 展开更多
关键词 BARLEY row type prbs MAPPING SSR
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Effect of row spacing and direction of sowing on yield and yield attributing characters of wheat cultivated in Western Chitwan, Nepal 被引量:5
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作者 Bisheshwor Prasad Pandey Komal Bahadur Basnet +3 位作者 Madan Raj Bhatta Shrawan Kumar Sah Resham Bahadur Thapa Tanka Prasad Kandel 《Agricultural Sciences》 2013年第7期309-316,共8页
A field experiment was conducted to study the growth and productivity of wheat as affected by row spacing and direction of sowing at Rampur, Chitwan, Nepal during the 2007-2008 wheat growing season. The experiment was... A field experiment was conducted to study the growth and productivity of wheat as affected by row spacing and direction of sowing at Rampur, Chitwan, Nepal during the 2007-2008 wheat growing season. The experiment was carried out in 3-factors factorial randomized complete block design comprising two varieties (Gautam and BL-2800), three row spacings (15, 20 and25 cm) and two row directions of sowing (east-west and north-south). The effects of variety and row direction of sowing on grain yield were significant (p < 0.05), but the grain yield was not affected by the row spacing treatment. BL-2800 variety produced higher grain yield (3.53 t·ha-1) as compared to Gautam (3.11 t·ha-1). Both wheat varieties yielded about 11% higher (p < 0.05) grain in the north-south sowing as compared to the eastwest sowing. 展开更多
关键词 Grain YIELD row Direction row Spacing TRITICUM AESTIVUM WHEAT Variety
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Effect of wide-narrow row arrangement in mechanical pot-seedling transplanting and plant density on yield formation and grain quality of japonica rice 被引量:29
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作者 HU Qun JIANG Wei-qin +7 位作者 QIU Shi XING Zhi-peng HU Ya-jie GUO Bao-wei LIU Guo-dong GAO Hui ZHANG Hong-cheng WEI Hai-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第5期1197-1214,共18页
Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machi... Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machine lacked optimized density spacing and limited yield potential for japonica rice. Therefore, ascertaining the optimized density by wide-narrow rows and the appropriate transplanting method for yield formation and grain quality of japonica rice is of great importance for high-quality rice production. Field experiments were conducted using two japonica rice cultivars Nanjing 9108 and Nanjing 5055 under three transplanting methods in 2016 and 2017: mechanical pot-seedling transplanting with wide-narrow row(K, average row spacing of 30 cm);equidistant row(D, 33 cm×12 cm);and mechanical carpet-seedling transplanting(T, 30 cm×12.4 cm). In addition, five different density treatments were set in K(K1–K5, from 18.62×10~4 to 28.49×10~4 hills ha^(–1)). The results showed that the highest yield was produced by a planting density of 26.88×104 hills ha^(–1) in mechanical pot-seedling transplanting with wide-narrow row with a greater number of total spikelets that resulted from significantly more panicles per area and slightly more grain number per panicle, as compared with equidistant row, and yield among density in wide-narrow row showed a parabolic trend. Compared with mechanical carpet-seedling transplanting, the treatment of the highest yield increased yield significantly, which was mainly attributed to the larger sink size with improved filled-grain percentage and grain weight, higher harvest index, and increased total dry matter accumulation, especially the larger amount accumulated from heading stage to maturity stage. With the density in wide-narrow row decreasing, processing quality, appearance quality, and nutrition quality were all improved, whereas amylose content and the taste value were decreased. Compared with mechanical carpet-seedling transplanting, mechanical pot-seedling transplanting improved processing quality and nutrition quality, but decreased amylose content and deteriorated appearance quality. These results suggested that mechanical pot-seedling transplanting with wide-narrow row coupling produced a suitable planting density of 26.88×10~4 hills ha^(–1) and may be an alternative approach to improving grain yield and quality for japonica rice. 展开更多
关键词 density grain quality JAPONICA rice TRANSPLANTING methods wide-narrow row yield formation
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Study of modeling unsteady blade row interaction in a transonic compressor stage part 2:influence of deterministic correlations on time-averaged flow prediction 被引量:3
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作者 Yang-Wei Liu Bao-Jie Liu Li-Peng Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期291-299,共9页
The average-passage equation system (APES) provides a rigorous mathematical framework for account- ing for the unsteady blade row interaction through multistage compressors in steady state environment by introducing... The average-passage equation system (APES) provides a rigorous mathematical framework for account- ing for the unsteady blade row interaction through multistage compressors in steady state environment by introducing de- terministic correlations (DC) that need to be modeled to close the equation system. The primary purpose of this study was to provide insight into the DC characteristics and the in- fluence of DC on the time-averaged flow field of the APES. In Part 2 of this two-part paper, the influence of DC on the time-averaged flow field was systematically studied; Several time-averaging computations boundary conditions and DC were conducted with various for the downstream stator in a transonic compressor stage, by employing the CFD solver developed in Part 1 of this two-part paper. These results were compared with the time-averaged unsteady flow field and the steady one. The study indicat;d that the circumferential- averaged DC can take into account major part of the unsteady effects on spanwise redistribution of flow fields in compres- sors. Furthermore, it demonstrated that both deterministic stresses and deterministic enthalpy fluxes are necessary to reproduce the time-averaged flow field. 展开更多
关键词 UNSTEADY Blade row interaction Compressor Deterministic correlation Average-passage equation system CFD
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Study of modeling unsteady blade row interaction in a transonic compressor stage part 1:code development and deterministic correlation analysis 被引量:5
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作者 Yang-Wei Liu Bao-Jie Liu Li-Peng Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期281-290,共10页
The average-passage equation system (APES) provides a rigorous mathematical framework for account- ing for the unsteady blade row interaction through multi- stage compressors in steady state environment by introduc-... The average-passage equation system (APES) provides a rigorous mathematical framework for account- ing for the unsteady blade row interaction through multi- stage compressors in steady state environment by introduc- ing deterministic correlations (DC) that need to be modeled to close the equation system. The primary purpose of this study is to provide insight into the DC characteristics and the influence of DC on the time-averaged flow field of the APES. In Part 1 of this two-part paper, firstly a 3D viscous unsteady and time-averaging flow CFD solver is developed to investi- gate the APES technique. Then steady and unsteady simu- lations are conducted in a transonic compressor stage. The results from both simulations are compared to highlight the significance of the unsteady interactions. Furthermore, the distribution characteristics of DC are studied and the DC at the rotor/stator interface are compared with their spatial cor- relations (SC). Lastly, steady and time-averaging (employing APES with DC) simulations for the downstream stator alone are conducted employing DC derived from the unsteady re- suits. The results from steady and time-averaging simula- tions are compared with the time-averaged unsteady results. The comparisons demonstrate that the simulation employing APES with DC can reproduce the time-averaged field and the 3D viscous time-averaging flow solver is validated. 展开更多
关键词 UNSTEADY Blade row interaction Compressor.Deterministic correlation. Average-passage equation system~ CFD
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Imaging features of solid pseudopapillary tumor of the pancreas on multi-detector row computed tomography 被引量:29
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作者 Deng-Bin Wang Qing-Bing Wang +2 位作者 Wei-Min Chai Ke-Min Chen Xia-Xing Deng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第7期829-835,共7页
AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant... AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential. METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P 〈 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6 cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly (P 〈 0.05).Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors. CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyrna and nearby structures in SPTs of the pancreas can be accurately revealed by MDCT preoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases. 展开更多
关键词 Solid pseudopapillary tumor PANCREAS Multi-detector row computed tomography Malignantpotential Aggressive behaviors
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Response of leaf carbon metabolism and dry matter accumulation to density and row spacing in two rapeseed(Brassica napus L.)genotypes with differing plant architectures 被引量:6
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作者 Jie Kuai Xiaoyong Li +4 位作者 Jianli Ji Zhen Li Yan Xie Bo Wang Guangsheng Zhou 《The Crop Journal》 SCIE CSCD 2022年第3期680-691,共12页
Biological yield indicates the potential for increasing yield.Leaf carbon metabolism plays an important role in the biomass accumulation of rapeseed(Brassica napus L.).Field experiments with the hybrid HZ62(with a con... Biological yield indicates the potential for increasing yield.Leaf carbon metabolism plays an important role in the biomass accumulation of rapeseed(Brassica napus L.).Field experiments with the hybrid HZ62(with a conventional plant architecture)grown in 2016–2017,and HZ62 and accession 1301(with a compact plant architecture)grown in 2017–2018 were conducted to characterize the physiological and proteomic responses of leaf photosynthetic carbon metabolism to density and row spacing configurations.The densities were set at 15×10;ha^(-1)(D1),30×10^(4)ha^(-1)(D2),and 45×10^(4)ha^(-1)(D3)(main plot),with row spacings of 15 cm(R15),25 cm(R25),and 35 cm(R35)(subplot).Individual and plant population biomass accumulation was greatest at R25,R15,and R15 for D1,D2,and D3,respectively,for both genotypes.In comparison with D1 R25,the individual aboveground biomass of HZ62 decreased by60.2%,whereas the population biomass increased by 31.9%,and the individual biomass of genotype1301 decreased by 54.0%and the population biomass increased by 53.9%at D3 R15.Leaf carbon metabolic enzymes varied between genotypes at flowering stage.In contrast to D1 R25,at D3 R15 the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)and sucrose phosphate synthase(SPS)and the contents of starch,sucrose and soluble sugars in leaves were significantly decreased in HZ62 and increased in genotype 1301.The activities of fructose-1,6-bisphosphatase(FBPase)decreased,in consistency with the abundance of fructose-bisphosphate aldolase in HZ62.In contrast,sucrose synthase(Su Sy)activity appeared to decrease in both genotypes,but a significant increase in abundance of a protein with sucrose synthase was found in the 1301 genotype by proteomic analysis.With increased density and reduced row spacing,the expression of most key proteins involved in carbon metabolism was elevated,and enzyme activity and carbon assimilate content were increased in 1301,whereas HZ62 showed the opposite trend,indicating that the compact plant type can accumulate more population biomass with denser planting. 展开更多
关键词 RAPESEED DENSITY row spacing Dry matter Leaf carbon metabolism
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Automatic Guidance of an Agricultural Tractor along with the Side Shift Control of the Attached Row Crop Cultivator 被引量:8
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作者 Javad Robati Hossein Navid +1 位作者 Mahdi Rezaei Amir Rikhtehgar Ghiasi 《Journal of Agricultural Science and Technology(B)》 2012年第1期151-158,共8页
This paper presents the automatic guidance system of an agricultural tractor and the side shift control of the attached row crop cultivator using electro-hydraulic actuators. In order to simulate the dynamic behaviour... This paper presents the automatic guidance system of an agricultural tractor and the side shift control of the attached row crop cultivator using electro-hydraulic actuators. In order to simulate the dynamic behaviour of the tractor along with the attached cultivator, the modified bicycle model was adopted. Steering angle sensor, fibre optic gyroscope (FOG) and RTK-DGPS technologies are assumed for measurements of the steering angle, yaw rate and the lateral position of the tractor, respectively. The kinematics model was used for the implement. In this study four cascade controllers were designed and simulated for tractor guidance which consists ofPD, PD, P and PID controllers. Other PI and PID controllers also had been designed for implement side shifting purpose. Then, these two systems were combined and the performance of the whole system was evaluated through the simulation results. According to the results tractor reaches the desired path after less than 10 seconds. Simulations showed that the maximum deviation of the tractor from the desired path was about 5 cm within this period. And the cultivator blades would follow the predetermined path with steady state error of about 5 cm too. 展开更多
关键词 row crop cultivator yaw rate servo valve servo cylinder cascade controller.
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