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烟雾病颞浅动脉-大脑中动脉分流术+脑-硬脑膜-颞肌血管融通术围手术期护理 被引量:11
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作者 刘靖 欧阳光 黄书岚 《中国临床神经外科杂志》 2019年第11期705-707,共3页
目的总结烟雾病行颞浅动脉-大脑中动脉(STA-MCA)分流术+脑-硬脑膜-颞肌血管融通术(EDMS)围手术期护理经验。方法回顾性分析2016年12月至2018年12月采用STA-MCA分流术+EDMS治疗58例烟雾病的临床资料,总结围手术期护理经验。结果58例中,3... 目的总结烟雾病行颞浅动脉-大脑中动脉(STA-MCA)分流术+脑-硬脑膜-颞肌血管融通术(EDMS)围手术期护理经验。方法回顾性分析2016年12月至2018年12月采用STA-MCA分流术+EDMS治疗58例烟雾病的临床资料,总结围手术期护理经验。结果58例中,3例出现脑过度灌注综合征,对症治疗2周后症状缓解;1例术后12 h出现癫痫发作;1例术后对侧肢体活动障碍,肌力Ⅲ级,经治疗后3个月复查肌力为Ⅳ级。结论烟雾病行STA-MCA分流术+EDMS治疗,加强围手术期护理,可有效提高手术效果,减少并发症。 展开更多
关键词 烟雾病 颞浅动脉-大脑动脉分流术术 脑-硬脑膜-颞肌血管融通术 围手术期护理
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FLOW800技术在STA-MCA分流术治疗烟雾病效果评估中的作用 被引量:4
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作者 王浩 章剑剑 陈劲草 《中国临床神经外科杂志》 2019年第8期449-452,共4页
目的探讨FLOW800技术在判断烟雾病颞浅动脉(STA)-大脑中动脉(MCA)分流术中血管吻合口通畅度及在手术治疗效果评估中的作用。方法回顾性分析2017年4月至2018年11月接STA-MCA分流术治疗的33例烟雾病的临床资料,手术前后应用FLOW800技术评... 目的探讨FLOW800技术在判断烟雾病颞浅动脉(STA)-大脑中动脉(MCA)分流术中血管吻合口通畅度及在手术治疗效果评估中的作用。方法回顾性分析2017年4月至2018年11月接STA-MCA分流术治疗的33例烟雾病的临床资料,手术前后应用FLOW800技术评估血管吻合口通畅情况及手术区域灌注改善情况。使用FLOW800软件对感兴趣区(ROI)进行分析,得到时间-荧光强度曲线,其中造影剂由动脉经循环后流至静脉的时间称为局部循环时间(MVTT),手术前后MVTT差值定义为ΔMVTT。结果33例均手术顺利,术中FLOW800分析均显示吻合口通畅。1因吻合口出现未行血管检查,其余32例吻合血管均通畅。术后11例发生并发症,其中低改善组6例(ΔMVTT<3 s),过改善组5例(ΔMVTT>3 s)。过改善组术前MVTT、ΔMVTT明显高于无并发症组和低改善组(P<0.05),而后两组均统计学差异(P>0.05)。受试者工作特征曲线分析结果显示ΔMVTT判断无并发症与低改善的最佳临界时间为1.635 s,敏感度和特异度分别为0.667和0.682;ΔMVTT判断无并发症与过改善的最佳临界时间为3.525 s,敏感度和特异度为别为1.000和0.727。结论FLOW800技术可准确评价烟雾病STA-MCA分流术中吻合口通畅程度,并在术后并发症的预测中起到一定的作用。 展开更多
关键词 烟雾病 颞浅动脉-大脑动脉分流 FLOW800技术 脑组织灌注
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颞浅动脉-大脑中动脉分流术对颅内动脉狭窄性脑卒中患者脑血流灌注及神经功能的影响 被引量:1
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作者 涂博 《临床医学工程》 2020年第9期1161-1162,共2页
目的观察颞浅动脉-大脑中动脉分流术对颅内动脉狭窄性脑卒中患者脑血流灌注及神经功能的影响。方法选取2018年2月至2019年1月我院收治的颅内动脉狭窄性脑卒中患者30例,均行颞浅动脉-大脑中动脉分流术,比较患者手术前后脑血流灌注指标、N... 目的观察颞浅动脉-大脑中动脉分流术对颅内动脉狭窄性脑卒中患者脑血流灌注及神经功能的影响。方法选取2018年2月至2019年1月我院收治的颅内动脉狭窄性脑卒中患者30例,均行颞浅动脉-大脑中动脉分流术,比较患者手术前后脑血流灌注指标、NIHSS评分及术后并发症发生情况。结果术后2周,患者的脑血流量高于术前,平均通过时间、患侧达峰时间短于术前(P<0.05);术后3个月,患者的NIHSS评分低于术前(P<0.05);术后仅3例患者出现头痛,经治疗后逐渐好转。结论颞浅动脉-大脑中动脉分流术可有效改善颅内动脉狭窄性脑卒中患者脑血流灌注,促进其神经功能恢复,且术后并发症较少,值得临床推广。 展开更多
关键词 颅内动脉狭窄性脑卒 颞浅动脉-大脑动脉分流 脑血流灌注 神经功能 并发症
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成人烟雾病STA-MCA分流术联合EMS后脑出血和高灌注综合征的关系 被引量:16
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作者 邱永逸 陈劲草 +4 位作者 章剑剑 余金 许双祥 张继波 王声播 《中国临床神经外科杂志》 2019年第7期387-389,共3页
目的探讨成人烟雾病颞浅动脉(STA)-大脑中动脉(MCA)分流术联合颞肌贴敷术(EMS)后脑出血和高灌注综合征的影响因素及其关系。方法回顾性分析2015年1月至2018年6月武汉大学中南医院神经外科连续收治的125例成人烟雾病的临床资料,均采用STA... 目的探讨成人烟雾病颞浅动脉(STA)-大脑中动脉(MCA)分流术联合颞肌贴敷术(EMS)后脑出血和高灌注综合征的影响因素及其关系。方法回顾性分析2015年1月至2018年6月武汉大学中南医院神经外科连续收治的125例成人烟雾病的临床资料,均采用STA-MCA分流术联合EMS治疗。结果术后发生高灌注综合征10例(7.04%),术后发生脑出血7例(4.93%)。发病早期(发病≤90 d)进行手术具有更高的并发症发生率(P<0.05)。术后发生高灌注综合征10例中,发生脑出血6例(60.0%);术后未发生高灌注综合征132例,发生脑出血1例(0.8%);两者具有显著性差异(P<0.05)。结论对于成人烟雾病,晚期(发病后>90 d)进行手术治疗,围手术期并发症发生率较低,术后高灌注综合征与术后脑出血关系密切。 展开更多
关键词 烟雾病 颞浅动脉-大脑动脉分流 颞肌贴敷术 高灌注综合征 脑出血
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SULZER中浓纸浆输送系统 被引量:3
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作者 肖德林 《中华纸业》 CAS 北大核心 2004年第3期30-32,共3页
以SULZER公司制造的MCE中浓浆泵、中浓混合器、中浓浆料分流排料器为例,介绍了中浓纸浆输送系统的设备原理、特点及应用等。
关键词 SUL ZER公司 浓纸浆输送系统 MCE浓浆泵 浓混合器 浓浆料分流排料器 工作原理
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斯科佩尔港拟建中欧物流中心
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《中外物流》 2006年第11期58-58,共1页
近日,斯科佩尔港董事会主席Rober Casta先生在科佩尔港水果恒温库建成仪式上介绍,科佩尔港计划在未来10年投资4.5亿欧元,建成中欧物流中心。投资计划包括:扩建1、2号货运码头;新建3号货运码头、货物分流中心及拥有1.2万个停车位的... 近日,斯科佩尔港董事会主席Rober Casta先生在科佩尔港水果恒温库建成仪式上介绍,科佩尔港计划在未来10年投资4.5亿欧元,建成中欧物流中心。投资计划包括:扩建1、2号货运码头;新建3号货运码头、货物分流中心及拥有1.2万个停车位的车场。新建成的水果恒温库,占地1.7万平方米,可存储1万吨进口水果。 展开更多
关键词 物流 进口水果 投资计划 董事会主席 分流 停车位 恒温
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“鑫飞鸿”投3000万美元在汕建物流中心
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《潮商》 2011年第2期67-67,共1页
乘搭海西经济区和经济特区扩至全市“顺风车”的汕头市,即将进入一个高速发展的新阶段。一些知名企业也把握好这个机遇,纷纷在汕增资扩产。中国十大速递品牌企业之一的广东鑫飞鸿(快递)集团准备在汕头市投资3000万美元,建立粤东物... 乘搭海西经济区和经济特区扩至全市“顺风车”的汕头市,即将进入一个高速发展的新阶段。一些知名企业也把握好这个机遇,纷纷在汕增资扩产。中国十大速递品牌企业之一的广东鑫飞鸿(快递)集团准备在汕头市投资3000万美元,建立粤东物流分流中心。 展开更多
关键词 物流 美元 海西经济区 经济特区 知名企业 品牌企业 分流 汕头市
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成人出血型烟雾病合并颅内动脉瘤的诊治及预后分析 被引量:5
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作者 李舜 唐晓平 +5 位作者 文军 罗仁国 张柳 段军伟 彭华 赵龙 《中国临床神经外科杂志》 2017年第4期213-215,共3页
目的探讨成人出血型烟雾病合并颅内动脉瘤的治疗方法。方法回顾性分析2010年7月至2015年3月收治的63例成人出血型烟雾病的临床资料,其中合并颅内动脉瘤8例。结果 63例中,蛛网膜下腔出血22例,伴发动脉瘤4例;脑室内出血35例,伴发动脉瘤4例... 目的探讨成人出血型烟雾病合并颅内动脉瘤的治疗方法。方法回顾性分析2010年7月至2015年3月收治的63例成人出血型烟雾病的临床资料,其中合并颅内动脉瘤8例。结果 63例中,蛛网膜下腔出血22例,伴发动脉瘤4例;脑室内出血35例,伴发动脉瘤4例;其他类型颅内出血6例,未发现颅内动脉瘤。8例伴发动脉瘤中,5例为主要动脉型动脉瘤,3例为外周动脉型动脉瘤;1例行开颅动脉瘤夹闭术+颞浅动脉-大脑中动脉(STA-MCA)分流术,5例行栓塞术+STA-MCA分流术,2例行保守治疗。所有病例出院后随访12~40个月,平均24个月;开颅夹闭+分流术或栓塞+分流术治疗的病人有较好疗效,无死亡及残疾,无再出血;2例保守治疗病人分别于初次发病后第11天、第20个月再出血死亡。结论对成人出血型烟雾病合并动脉瘤,可行开颅夹闭或栓塞处理动脉瘤,再行STA-MCA分流术,预后较好;若为外周动脉型动脉瘤,不能栓塞可予保守治疗,但疗效不确切,可再发颅内出血。 展开更多
关键词 娴雾病 动脉瘤 颅内出血 动脉瘤夹闭术 颞浅动脉-大脑动脉分流 成人
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李斯特经济学的历史地位、性质与重大现实意义 被引量:18
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作者 贾根良 《学习与探索》 CSSCI 北大核心 2015年第1期81-88,共8页
李斯特经济学总结了英国工业革命及其以前西方世界兴衰的经验教训,是经济学中最早系统地揭示欠发达国家向发达国家转变的历史规律的经济学说,对美国和德国的兴起产生了重大影响,并是导致中日两国在近现代史上发展道路"大分流"... 李斯特经济学总结了英国工业革命及其以前西方世界兴衰的经验教训,是经济学中最早系统地揭示欠发达国家向发达国家转变的历史规律的经济学说,对美国和德国的兴起产生了重大影响,并是导致中日两国在近现代史上发展道路"大分流"及其截然不同命运的首要根源。"二战"后的冷战环境导致了李斯特经济学的衰微,国际金融危机的爆发呼唤李斯特经济学的归来。李斯特经济学所开辟的发展道路曾是历史上发达国家崛起的普遍道路,而"中国模式说"却假定了"中国例外论"。为了解决中国目前所面临的重大挑战,我们开设了"纪念李斯特经济学传入中国90周年"的专题讨论,其目的就在于"为往圣继绝学",改变李斯特经济学在中国被边缘化的状态,并在探索适合中国国情的经济发展新模式的过程中,创建中国的"新李斯特学派"。 展开更多
关键词 李斯特经济学 西方世界的兴起 日大分流 国模式 国例外论 新李斯特学派
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Effects of BYHW Decoction and Its Effective Constituents on the Fluidity of the Cell Membrane in a Stroke-Modeled Rat Brain 被引量:3
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作者 卢景芬 李晨旭 +4 位作者 古力努尔 李廷凤 屠鹏飞 殷俊杰 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第4期132-136,共5页
With in vitro spin labeling electron spin resonance (ESR) spectroscopy, we have studied the effects of Bu Yang Huan Wu (BYHW) decoction and its effective constituents such as astragaloside IV ferulic acid, chua... With in vitro spin labeling electron spin resonance (ESR) spectroscopy, we have studied the effects of Bu Yang Huan Wu (BYHW) decoction and its effective constituents such as astragaloside IV ferulic acid, chuanxiongzine, rutin, chlorogenic acid, 9,10 dimethoxy pterocarpane 7 O β D glucoside, calycosin, formononetin, calycosin 7 O glucoside, paeoniflorin, paeonal and quercein on the cell membrane fluidity of a rat brain which was modeled after the dual cervical arteries were intercepted and released for realizing an ischemia reperfusion injury which was selected as a brain stroke model. Our results indicated that the cell membrane fluidity in the model group decreased approximately 8% compared with the control group, and after brain cells were incubatied with species, the membrane fluidity could be recovered closely to the control level depending on the BYHW decoction and its different constituents. As the membrane fluidity is a very sensitive biological index which reflectsd the cell status, our method will be useful to study the molecular mechanism of tradition Chinese medicine (TCM) and its combination recipe. 展开更多
关键词 Bu Yang Huan Wu decoction Brain stroke Cell membrane fluidity ESR
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Analysis of anthropogenic aluminum cycle in China 被引量:4
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作者 岳强 王鹤鸣 +1 位作者 陆钟武 智升科 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1134-1144,共11页
Anthropogenic aluminum cycle in China was analyzed by the aluminum flow diagram based on the life cycle of aluminum products. The whole anthropogenic aluminum cycle consists of four stages: alumina and aluminum produ... Anthropogenic aluminum cycle in China was analyzed by the aluminum flow diagram based on the life cycle of aluminum products. The whole anthropogenic aluminum cycle consists of four stages: alumina and aluminum production, fabrication and manufacture, use and reclamation. Based on the investigation on the 2003-2007 aluminum cycles in China, a number of changes can be found. For instance, resources self-support ratio (RSR) in alumina production dropped from 95.42%to 55.50%, while RSR in the aluminum production increased from 52.45%to 79.25%. However, RSR in the Chinese aluminum industry leveled off at 50%in the period of 2003-2007. The respective use ratios of domestic and imported aluminum scrap in the aluminum industry of 2007 were 5.38% and 9.40%. In contrast, both the net imported Al-containing resources and the lost quantity of Al-containing materials in aluminum cycle increased during the same period, as well as the net increased quantity of Al-containing materials in social stock and recycled Al-scrap. Proposals for promoting aluminum cycle were put forward. The import/export policy and reducing the loss of Al-containing materials for the aluminum industry in China in the future were discussed. 展开更多
关键词 ANTHROPOGENIC aluminum cycle in China SFA weighted average method average use life
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“中国情境”下的议题识别及其价值——基于“中西分流“”中日分流”的探讨
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作者 梁华 《南开学报(哲学社会科学版)》 CSSCI 北大核心 2019年第5期99-107,共9页
就从农业文明向工业文明转变初期的近代中国而言,'中西分流'议题的核心价值在于,通过和已经崛起的工业文明代表欧洲比较,揭示转变的大趋势。但在解释这种大趋势的转变时,把原因归为英国独有的'环境和生态'因素,又将议... 就从农业文明向工业文明转变初期的近代中国而言,'中西分流'议题的核心价值在于,通过和已经崛起的工业文明代表欧洲比较,揭示转变的大趋势。但在解释这种大趋势的转变时,把原因归为英国独有的'环境和生态'因素,又将议题带回了'西方情境'。就被工业化浪潮裹挟前进的近代中国来说,'中日分流'议题的核心价值在于,通过和转型成功的代表日本比较,揭示经济制度构想和建设的多样性,从而更为彻底地把研究旨趣从'西方情境'引向'中国情境'。经历了一个半世纪的探索,中国特色经济制度建设路径逐渐形成,因此,走入'中国情境',发现问题,设置议题,方显哲学社会科学学科、学术和话语体系的中国特色。 展开更多
关键词 议题设置 西分流 分流 国工业化
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Effects of Chinese herbs on salivary fluid secretion by isolated and perfused rat submandibular glands 被引量:9
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作者 Masataka Murakami Mu-Xin Wei +1 位作者 Wei Ding Qian-De Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第31期3908-3915,共8页
AIM: TO determine whether Chinese herbs (CHs) relieve xerostomia (dry mouth) by increasing salivary secretion. METHODS: The submandibular glands of Wistar rats were surgically isolated and perfused arterially wi... AIM: TO determine whether Chinese herbs (CHs) relieve xerostomia (dry mouth) by increasing salivary secretion. METHODS: The submandibular glands of Wistar rats were surgically isolated and perfused arterially with buffered salt solution. After control perfusion, recording started 5 min prior to the start of stimulation. After fluid secretion was induced by 0.2 μmol/L carbamylcholine (CCh) in the perfusate for 10 min, Chinese herb (CH) was added in the perfusion for 5 min. CCh was then overloaded at 0.2 μmol/L in the perfusion for 20 min. The volume of salivary fluid secretion was recorded by a computer-controlled balance system. RESULTS: Saliva secretion formed an initial ephemeral peak at 30 s followed by a gradual increase to a sustained level. CH alone induced no or little saliva in all types of CH selected. During perfusion with CH,overloading of CCh promoted fluid secretion in 1S of 20 CHs. This promotion was classified into four patterns, which were eventually related to the categories of CH: Overall sustained phase was continuously raised (Yin-nourishing, fluid production-promoting and heatclearing agents); The sustained secretion rose to reach a maximum then decreased (Qi-enhancing agent); Sustained secretion rose to reach the highest maximum and was then sustained with a slight decline (swelling-reducing, phlegm-resolving and pus-expelling agents); Stimulation of salivary secretion without any added stimulants. Addition of CCh raised the fluid secretion to reach the highest maximum then sharply decreased to a lower sustained level (blood activating agent). CONCLUSION: The present findings lead to the conclusion that various CHs have different promotional effects directly on the salivary gland. 展开更多
关键词 Chinese herbs Salivary secretion Submandibular glands XEROSTOMIA
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新冠肺炎疫情背景下应急性建筑的结构设计实践与思考 被引量:6
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作者 刘挺 王术春 +2 位作者 孙娜 和超 刘芳 《建筑结构》 CSCD 北大核心 2021年第3期27-31,46,共6页
西安咸阳国际机场旅客应急分流转运中心是为应对新冠肺炎疫情而新建的应急性建筑,从开工建设到交付使用需在7d之内完成,为此,设计及施工均采取了非常规的措施,最终该项目仅用时5d建成。工程实践表明,应急性建筑的结构设计与常规条件下... 西安咸阳国际机场旅客应急分流转运中心是为应对新冠肺炎疫情而新建的应急性建筑,从开工建设到交付使用需在7d之内完成,为此,设计及施工均采取了非常规的措施,最终该项目仅用时5d建成。工程实践表明,应急性建筑的结构设计与常规条件下的结构设计存在诸多差异。对该工程的结构设计做了详细介绍,并对应急性建筑的结构设计做了深入分析与思考。最后,提出应急性建筑的结构设计应以“安全适用、建造快捷、便于维护”为原则。 展开更多
关键词 应急性建筑 旅客分流 结构设计 门式刚架 设计原则
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Prevalence of hepatitis C virus infection among hemodialysis patients in the Middle-East: A systematic review and meta-analysis 被引量:8
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作者 Soheil Ashkani-Esfahani Seyed Moayed Alavian Mohammad Salehi-Marzijarani 《World Journal of Gastroenterology》 SCIE CAS 2017年第1期151-166,共16页
AIM To determine hepatitis C virus(HCV)infection prevalence in each country of the Middle-East and the overall prevalence of the region.METHODS In this systematic review,we gathered all documents related to HCV infect... AIM To determine hepatitis C virus(HCV)infection prevalence in each country of the Middle-East and the overall prevalence of the region.METHODS In this systematic review,we gathered all documents related to HCV infection prevalence among hemodialysis patients in 17 middle-east countries from April 2006 to March 2016.We selected only cross-sectional studies that had proper sampling and measurement methods as well as a valid statistical analysis.RESULTS After screening of 7311 documents,56 studies were selected reporting the prevalence of HCV infection among hemodialysis patients from 10 countries of the region.Seven countries including United Arab Emirates,Afghanistan,Qatar,Bahrain,Kuwait,Oman,Israel,and Cyprus did not have any relevant document;thus,their latest reports were just mentioned.We performed the meta-analysis and determined the prevalence rates for each country as well as the whole region.The overall HCV infection prevalence among hemodialysis patients in the region was reported to be 25.3%;Egypt and Syria had the highest reported rates while Iran and Lebanon had the lowest.Further investigations are still needed to provide more reliable databases,find main risk factors,and to improve diagnosis and treatment plans,particularly in higher prevalent countries.CONCLUSION Controlling the prevalence and improving the management methods of HCV infection among hemodialysis patients are of a great concern in the Middle-East region. 展开更多
关键词 Hepatitis C HEMODIALYSIS PREVALENCE MIDDLE-EAST META-ANALYSIS REVIEW
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An Improved Genetic Algorithm for Allocation Optimization of Distribution Centers 被引量:7
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作者 钱晶 庞小红 吴智铭 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期73-76,共4页
This paper introduced an integrated allocation model for distribution centers (DCs). The facility cost, inventory cost, transportation cost and service quality were considered in the model. An improved genetic algorit... This paper introduced an integrated allocation model for distribution centers (DCs). The facility cost, inventory cost, transportation cost and service quality were considered in the model. An improved genetic algorithm (IGA) was proposed to solve the problem. The improvement of IGA is based on the idea of adjusting crossover probability and mutation probability. The IGA is supplied by heuristic rules too. The simulation results show that the IGA is better than the standard GA(SGA) in search efficiency and equality. 展开更多
关键词 distribution center allocation optimization improved genetic algorithm
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A COMPREHENSIVE ANALYSIS OF INTERACTIONS BETWEEN MESO-SCALE CONVECTIVE CLOUD CLUSTERS IN TYPHOONS AND MESOSCALE HEAVY RAINS 被引量:1
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作者 林毅 刘爱鸣 林新彬 《Journal of Tropical Meteorology》 SCIE 2003年第1期80-85,共6页
In this paper, time and space distribution regularity of meso-scale heavy rains in five selected typhoons which landed at Fujian from 1996 to 1998 has been analyzed. Besides, with hourly digitized satellite infrared i... In this paper, time and space distribution regularity of meso-scale heavy rains in five selected typhoons which landed at Fujian from 1996 to 1998 has been analyzed. Besides, with hourly digitized satellite infrared imagery, the features of the mesoscale are revealed for the genesis and evolution of mesoscale convective systems in typhoons. It indicates that the intensity of mesoscale storms is closely connected with the temperature and the area of the coldest cloud cluster. The heavy rainfall usually emerges on the eastern side of the mesoscale convective cloud clusters, where the cloud mass is developing and with a dense gradient and big curvature of isoline of the cloud top temperature. 展开更多
关键词 TYPHOONS MESOSCALE heavy rains convective cloud clusters
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Effects of Tillage Management on Infiltration and Preferential Flow in a Black Soil, Northeast China 被引量:8
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作者 FAN Ruqin ZHANG Xiaoping +3 位作者 YANG Xueming LIANG Aizhen JIA Shuxia CHEN Xuewen 《Chinese Geographical Science》 SCIE CSCD 2013年第3期312-320,共9页
The impacts of no-tillage (NT) and moldboard plough (MP) managements on infiltration rate and preferential flow were characterized using a combined technique of double-ring device and dye tracer on a black soil (... The impacts of no-tillage (NT) and moldboard plough (MP) managements on infiltration rate and preferential flow were characterized using a combined technique of double-ring device and dye tracer on a black soil (Mollisols) in Northeast China. The ob- jective of this study is to evaluate how tillage practices enhance soil water infiltration and preferential flow in favor of soil erosion con- trol in the study area. The steady infiltration rates under NT management are 1.6 and 2.1 times as high as those under MP management in the 6th and 8th years of the tillage management in place, while the infiltrated water amounts under NT management are 1.4 and 2.0 times as high as those under MP management, respectively. The depth of methylene blue penetrated into NT soil increases from 43 cm in the 6th year to 57 cm in the 8th year, which are 16 cm and 19 em deeper than those in MP soil, respectively. The results of morphol- ogic image show that more biological macro-pores occur in NT soil than in MP soil. These macro-pores play a key role in enhancing preferential flow in NT soil, which in turn promotes water infiltration through preferential pathways in NT soil. The results are helpful to policy-making in popularizing NT and have the implications for tillage management in regard to soil erosion control in black soil region of China. 展开更多
关键词 NO-TILLAGE moldboard plough dye tracer macro-pore black soil Northeast China
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A STUDY OF PARTITIONING Q VECTOR ON BACKGROUND CONDITIONS OF A TORRENTIAL RAINFALL OVER SHANGHAI,CHINA ON 25 AUGUST 2008 被引量:4
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作者 岳彩军 鲁小琴 +1 位作者 李小凡 宗志平 《Journal of Tropical Meteorology》 SCIE 2011年第3期231-247,共17页
A rainfall that occurred during 0200–1400 Beijing Standard Time(BST)25 August 2008 shows the rapid development of a convective system,a short life span,and a record rate of 117.5 mm h-1for Xujiahui station since 1872... A rainfall that occurred during 0200–1400 Beijing Standard Time(BST)25 August 2008 shows the rapid development of a convective system,a short life span,and a record rate of 117.5 mm h-1for Xujiahui station since 1872.To study this torrential rainfall process,the partitioning method of Q vector is developed,in which a moist Q vector is first separated into a dry ageostrophic Q vector(DQ)and a diabatic-heating component.The dry ageostrophic Q vector is further partitioned along isothermal lines in the natural coordinate to identify different scale forcing in adiabatic atmosphere,and the large-scale and convective condensational heating in non-uniform saturated atmosphere,convective condensational heating, and Laplace of diabatic heating that includes radiative heating and other heating and cooling processes,are calculated to study the forcing from diabatic heating.The effects of the environmental conditions on the development of the rainfall processes are diagnosed by performing the partitioning of Q vector based on 6-hourly NCEP/NCAR Final Analysis(FNL)data with the horizontal resolution of 1°×1°.The results include the following:(1)a low-pressure inverted trough associated with the landfall of Typhoon Nuri (2008),a strong southwesterly jet along the western side of the subtropical high,and an eastward-propagating westerly low-pressure trough provide favorable synoptic conditions for the development of torrential rainfall;(2)the analysis of DQ vector showed that the upward motions forced by the convergence of DQ vector in the lower troposphere(1000–600 hPa)favor the development of torrential rainfall.When DQ vector converges in the upper troposphere(500–100 hPa),upward motions in the whole air column intensify significantly to accelerate the development of torrential rainfall;(3)the partitioning analysis of DQ vector reveals that large-scale forcing persistently favors the development of torrential rainfall whereas the mesoscale forcing speeds up the torrential rainfall;(4)the calculations of large-scale condensational heating in non-uniform saturated atmosphere,convective condensational heating, and Laplace of diabatic heating showed that the forcing related to diabatic heating has the positive feedback on the convective development,and such positive feedback decays and dissipates when the convective system propagates eastward and weakens. 展开更多
关键词 background conditions of torrential rainfall partitioning of Q vector dry ageostrophic Q vector diabatic heating
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CFD modelling and optimization of oxygen supply mode in KIVCET smelting process 被引量:4
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作者 Jia-dong LI Ping ZHOU +3 位作者 Zhou LIAO Li-yuan CHAI Chenn Q. ZHOU Ling ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1560-1568,共9页
The influence of oxygen supply mode on the KIVCET (a Russian acronym for flash?cyclone?oxygen?electric?smelting) process was investigated using numerical simulation. The mass rate ratio (MRR) of central oxygen to late... The influence of oxygen supply mode on the KIVCET (a Russian acronym for flash?cyclone?oxygen?electric?smelting) process was investigated using numerical simulation. The mass rate ratio (MRR) of central oxygen to lateral oxygen of the central jet distributor (CJD) burner was defined to express the oxygen supply mode, and the KIVCET process with an MRR ranging from 0.09 to 0.39 was simulated. The results show that there are four efficient reaction regions that correspond to four CJD burners. A higher central oxygen flow improves the mixing between particles and oxygen, thus enhancing reactions and shortening the reaction regions. However, a higher dust rate is induced due to the spread of the particle columns. The optimal MRR for a KIVCET furnace with a smelting capacity of 50000 kg/h is suggested to be 0.31. In this case, the chemical reactions associated with the feed are completed with an acceptable dust rate. 展开更多
关键词 KIVCET furnace central jet distributor (CJD) burner computational fluid dynamics (CFD) central oxygen lateral oxygen optimization
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