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"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy 被引量:1
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作者 Xiao-Si Hu Yong Wang +5 位作者 Hong-Tao Pan Chao Zhu Shi-Lei Chen Hui-Chun Liu Qing Pang Hao Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期503-510,共8页
BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require furt... BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application. 展开更多
关键词 Five steps four quadrants Hepatic hilum lymph node Modularized en bloc clearance Laparoscopic pancreaticoduodenectomy
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Half-integer Shapiro steps in MgB_(2) focused He ion beam Josephson junctions
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作者 殷大利 蔡欣炜 +5 位作者 徐铁权 孙瑞宁 韩颖 张焱 王越 甘子钊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期483-489,共7页
Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(C... Half-integer microwave induced steps(Shapiro steps)have been observed in many different Josephson junction systems,which have attracted a lot of attention because they signify the deviation of current phase relation(CPR)and uncover many unconventional physical properties.In this article,we first report the discovery of half-integer Shapiro steps in MgB_(2)focused He ion beam(He-FIB)Josephson junctions.The half-integer steps'dependence on microwave frequency,temperature,microwave power,and magnetic field is also analyzed.We find that the existence of half-integer steps can be controlled by the magnetic field periodically,which is similar to that of high temperature superconductor(HTS)grain boundary junctions,and the similarity of the microstructures between gain boundary junctions and He-FIB junctions is discussed.As a consequence,we mainly attribute the physical origin of half-integer steps in MgB_(2)He-FIB junctions to the model that a He-FIB junction is analogous to a parallel junctions'array.Our results show that He-FIB technology is a promising platform for researching CPR in junctions made of different superconductors. 展开更多
关键词 Josephson junction half-integer Shapiro steps MgB_(2) focused helium ion beam
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A Clean Switch Inner Mongolian town takes giant steps in transitioning to clean energy production
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作者 XIA YUANYUAN 《ChinAfrica》 2024年第5期34-36,共3页
Staff at the Ruichen Wanniu Livestock Farm in Jungar Zhao Town,Jungar Banner,Inner Mongolia,are consistently busy,even during important festivals.
关键词 CLEAN steps BANNER
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In Her Father's Footsteps
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作者 LI XIAOYU 《ChinAfrica》 2023年第4期30-31,共2页
Chinese nurse chooses to join a medical mission to Mali, just like her father Hong Min will never forget 18 July 2017. It was the day when the nurse received the medal of the Order of Health Merit of Mali for her serv... Chinese nurse chooses to join a medical mission to Mali, just like her father Hong Min will never forget 18 July 2017. It was the day when the nurse received the medal of the Order of Health Merit of Mali for her service in the country as part of the 24th Chinese medical team.The award, in the words of Samba Ousmane Sow, then minister of health and public hygiene. 展开更多
关键词 NURSE WORDS steps
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疏散模拟软件STEPS与Pathfinder对比研究 被引量:40
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作者 杜长宝 朱国庆 李俊毅 《消防科学与技术》 CAS 北大核心 2015年第4期456-460,共5页
为了了解两款疏散模拟软件STEPS与Pathfinder的功能差异及适用范围,采用理论研究与实际模拟相结合的方法进行对比分析。研究发现:STEPS软件采用元胞自动机(CA)模型,疏散规则简单,人员智能化程度低,疏散时人员行为特征与现实情况不完全相... 为了了解两款疏散模拟软件STEPS与Pathfinder的功能差异及适用范围,采用理论研究与实际模拟相结合的方法进行对比分析。研究发现:STEPS软件采用元胞自动机(CA)模型,疏散规则简单,人员智能化程度低,疏散时人员行为特征与现实情况不完全相符,但路径决策系统很好地解决了上述问题,可以真实地模拟常态下人员疏散;Pathfinder软件采用Agent-based模型,人员智能化程度高,个体可以回应环境刺激,人员可以轻松规避障碍物,人群中的个体行为特征丰富且与现实情况十分相符,但在出口选择上存在缺陷,人员只能选择前方的出口而忽略后方的出口,不能模拟常态下的人员疏散。分析得出,Pathfinder模拟结果与真实情况相符程度更高,STEPS更适合模拟常态下人员疏散。 展开更多
关键词 安全疏散 steps 元胞自动机 PATHFINDER Agent-base
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基于STEPS的某高校学生宿舍楼人群疏散 被引量:2
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作者 王丽 任常兴 曾坚 《消防科学与技术》 CAS 北大核心 2017年第6期779-781,共3页
建立实际的宿舍楼模型,通过STEPS进行模拟,研究宿舍楼出口数量、宽度、位置等因素对人员疏散时间的影响。根据不同疏散出口的开启情况设置7个场景,分析不同时刻的人员分布、不同场景下的疏散时间以及不同场景下各出口的利用率等。建议... 建立实际的宿舍楼模型,通过STEPS进行模拟,研究宿舍楼出口数量、宽度、位置等因素对人员疏散时间的影响。根据不同疏散出口的开启情况设置7个场景,分析不同时刻的人员分布、不同场景下的疏散时间以及不同场景下各出口的利用率等。建议此宿舍楼在突发状况下至少开启2个疏散出口,并对人员疏散加以引导。 展开更多
关键词 steps 学生宿舍楼 疏散出口 疏散时间 出口利用率 建筑防火
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基于STEPS的山区高含硫气井周边居民疏散模拟研究 被引量:1
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作者 王丽 刘茂 孟博 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第6期81-87,共7页
我国高含硫气井都位于一些远郊区或偏远山区,在生产运行中已多次因出现井喷、井口溢气等险情而疏散周边居民.以山区某高含硫气井周围1 km内的居民疏散为研究对象,针对当地山峦起伏、山路坡陡等复杂地形的特点,使用STEPS软件进行模拟.根... 我国高含硫气井都位于一些远郊区或偏远山区,在生产运行中已多次因出现井喷、井口溢气等险情而疏散周边居民.以山区某高含硫气井周围1 km内的居民疏散为研究对象,针对当地山峦起伏、山路坡陡等复杂地形的特点,使用STEPS软件进行模拟.根据NASA 2009年的全球DEM数据、航拍图和实地调研结果,提供了在软件中直接绘制山区三维地形和道路网络模型的方法.在人员属性的设置中,考虑了地形坡度对不同性别和年龄的人员移动速度的影响.最后通过STEPS模拟,研究了气井周围三条主要道路上的疏散时间、疏散效率以及不同类型人员的疏散. 展开更多
关键词 山区 高含硫气井 复杂地形 steps 三维疏散模拟
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基于STEPS的音乐厅人员疏散模拟研究 被引量:2
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作者 李大燕 朱国庆 《消防科学与技术》 CAS 北大核心 2016年第8期1080-1083,共4页
介绍元胞自动机理论和STEPS软件。研究音乐厅人员疏散的设计,运用STEPS软件,分析火灾导致某安全出口失效的情况下音乐厅人员疏散过程,分析其他安全出口的利用率。模拟结果显示,安全出口利用不均衡,人员在疏散楼梯口以及个别直通室外的... 介绍元胞自动机理论和STEPS软件。研究音乐厅人员疏散的设计,运用STEPS软件,分析火灾导致某安全出口失效的情况下音乐厅人员疏散过程,分析其他安全出口的利用率。模拟结果显示,安全出口利用不均衡,人员在疏散楼梯口以及个别直通室外的安全出口发生拥堵。建议增大安全出口宽度,合理分流,统筹疏散;制定完善的管理制度和维护措施。将STEPS模拟结果与Pathfinder模拟结果进行对比,模拟结果基本一致。 展开更多
关键词 元胞自动机 steps 音乐厅 人员疏散 疏散模拟 建筑防火
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基于STEPS的超高层建筑人员疏散模拟研究 被引量:3
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作者 白磊 王刘兵 《消防科学与技术》 北大核心 2017年第6期776-779,共4页
选取某超高层写字楼,使用STEPS软件进行人员疏散模拟。按照建筑设计容量和人员密度计算各楼层的人员荷载。将楼梯、不同分布高度的电梯、避难层三种疏散设施相组合,设置5种疏散方案进行模拟研究,得出不同方案下建筑内部剩余人数随时间... 选取某超高层写字楼,使用STEPS软件进行人员疏散模拟。按照建筑设计容量和人员密度计算各楼层的人员荷载。将楼梯、不同分布高度的电梯、避难层三种疏散设施相组合,设置5种疏散方案进行模拟研究,得出不同方案下建筑内部剩余人数随时间变化的曲线以及不同方案中由电梯疏散的人数占总人数的百分比,分析各疏散方案的疏散效率。研究结果表明,"楼梯+电梯+避难层"的组合为最优疏散方案,疏散效率和安全性最高。 展开更多
关键词 超高层建筑 steps 人员疏散 电梯疏散 避难层 疏散效率
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基于STEPS的历史地段火灾疏散模拟研究 被引量:5
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作者 朱剡 《上海城市规划》 2016年第1期45-50,共6页
作为具有生命力的遗产,历史地段不断受到来自火灾的严重威胁。在保护历史地段自身安全的同时,地段内公众的疏散避难安全应得到保证。为了在保护历史地段的基础上保障公众的火灾疏散避难安全性,应用基于细胞自动机的理论的STEPS软件,以... 作为具有生命力的遗产,历史地段不断受到来自火灾的严重威胁。在保护历史地段自身安全的同时,地段内公众的疏散避难安全应得到保证。为了在保护历史地段的基础上保障公众的火灾疏散避难安全性,应用基于细胞自动机的理论的STEPS软件,以宁波走马塘古村落为例,以疏散时间、出口距离、通道使用强度3个指标为依据,对历史地段进行火灾疏散避难模拟分析,对历史地区空间规划提出相应的改造策略,并进行进一步的模拟验证。 展开更多
关键词 历史地段 火灾 steps软件 疏散模拟
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英格兰青少年足球训练理论与实践分析——基于四角模型和STEPS原则 被引量:6
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作者 陈志辉 梁斌 田建强 《海南师范大学学报(自然科学版)》 CAS 2017年第1期99-104,共6页
文章运用实地访谈法、文献资料法等方法对英格兰青少年足球运动员训练培养的内容与方法进行了研究.通过分析训练实例得出,四角模型能从技术、体能、心理和社交四个方面综合培养青少年足球运动员的比赛能力;STEPS原则广泛应用于英格兰青... 文章运用实地访谈法、文献资料法等方法对英格兰青少年足球运动员训练培养的内容与方法进行了研究.通过分析训练实例得出,四角模型能从技术、体能、心理和社交四个方面综合培养青少年足球运动员的比赛能力;STEPS原则广泛应用于英格兰青少年各个年龄阶段的足球训练,且不同年龄阶段培养、发展技能的侧重点十分明确;在训练内容的安排上,注重进阶,接近实战,训练内容和方法具有科学性、针对性和全面性.文章旨在为我国青少年足球运动员的训练培养提供参考. 展开更多
关键词 四角模型 steps原则 英格兰
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在STEPS中的三维宿舍火灾的人群疏散研究 被引量:2
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作者 唐涛 李星华 +1 位作者 何亮 李连营 《地理空间信息》 2011年第1期91-93,96,共4页
在STEPS里建立了一个三维火灾逃生模型,在这个模型当中,首先找到最近的安全出口模拟人群疏散,同时记录每个时段的疏散人数及总的疏散时间;然后以此来研究起火楼层、备用出口的位置和个数、人的反应时间一致性等因素对总的疏散时间的影响。
关键词 steps Fruin分布 疏散时间 正态分布
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远程抄表STEPS系统在校园中的应用 被引量:1
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作者 万彬 喻恺 章继涛 《江西科技学院学报》 2006年第2期75-80,共6页
本文阐述了远程集中抄表系统与传统抄表模式的比较,结合我国校园自身的特点,建立和推出适合学校用电管理状况的新型的三层用电管理系统(STEPS)。为学校的用电管理系统在现行的用电管理系统的基础上探索出一条行之有效的新路和解决方案。
关键词 传统抄表的比较 steps 用电管理系统 集抄系统
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Recovery of waste rare earth fluorescent powders by two steps acid leaching 被引量:17
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作者 Shen-Gen Zhang Min Yang +2 位作者 Hu Liu De-An Pan Jian-Jun Tian 《Rare Metals》 SCIE EI CAS CSCD 2013年第6期609-615,共7页
The effects of the acid leaching and alkali fusion on the leaching efficiency of Y,Eu,Ce,and Tb from the waste rare earth fluorescent powders were investigated in this paper.The results show that hydrochloric acid is ... The effects of the acid leaching and alkali fusion on the leaching efficiency of Y,Eu,Ce,and Tb from the waste rare earth fluorescent powders were investigated in this paper.The results show that hydrochloric acid is better than sulfuric acid in the first acid leaching,and NaOH is better than Na2CO3in the alkali fusion.In the first acid leaching,the Wloss is 20.94%when the waste rare earth fluorescent powders are acid leached in H?concentration 3 mol L-1and S/L ratio 1:3 for 4 h due to red powders dissolved.The better results of the alkali fusion can be got at 800℃ for 2 h when the NaOH is used.The blue powders and the green powders can be dissolved into NaAlO2and oxides such as rare earth oxide(REO).The REO can be dissolved in H?concentration 5 mol L-1,S/L1:10 for 3 h in the second acid leaching.The leaching rates of the Y,Eu,Ce,and Tb are 99.06%,97.38%,98.22%,and 98.15%,respectively.The leaching rate of the total rare earth is 98.60%. 展开更多
关键词 Waste rare earth fluorescent powders Two steps acid leaching Alkali fusion
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基于STEPS的某学校餐厅人员疏散模拟研究 被引量:6
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作者 周晓峰 《中国制造业信息化(应用版)》 2008年第12期66-68,共3页
本文基于STEPS计算机安全疏散模拟软件,对典型人员密集场所某学校餐厅人员疏散进行了研究,首先建立了合理简化后的某学校餐厅的疏散模型。通过STEPS模拟,主要研究了餐厅不同满座率对人员疏散时间的影响;研究了是否使用备用疏散楼梯对疏... 本文基于STEPS计算机安全疏散模拟软件,对典型人员密集场所某学校餐厅人员疏散进行了研究,首先建立了合理简化后的某学校餐厅的疏散模型。通过STEPS模拟,主要研究了餐厅不同满座率对人员疏散时间的影响;研究了是否使用备用疏散楼梯对疏散时问的影响,量化了使用备用楼梯的作用;研究了疏散时各楼梯的使用情况,提出了确定更加合理的人员疏散楼梯使用比例的方法,为安全紧急疏散分区提供理论依据,为进一步缩短了疏散时间,提高了人员安全疏散水平指明方向。 展开更多
关键词 人员疏散 steps 模拟
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Three-Steps-Meshing Based Multiple Crack Identification for Structures and Its Experimental Studies 被引量:3
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作者 LI Bing CHEN Xuefeng HE Zhengjia 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期400-405,共6页
Multiple crack identification plays an important role in vibration-based crack identification of structures. Traditional crack detection method of single crack is difficult to be used in multiple crack diagnosis. A th... Multiple crack identification plays an important role in vibration-based crack identification of structures. Traditional crack detection method of single crack is difficult to be used in multiple crack diagnosis. A three-step-meshing method for the multiple cracks identification in structures is presented. Firstly, the changes in natural frequency of a structure with various crack locations and depth are accurately obtained by means of wavelet finite element method, and then the damage coefficient method is used to determine the number and the region of cracks. Secondly, different regions in the cracked structure are divided into meshes with different scales, and then the small unit containing cracks in the damaged area is gradually located by iterative computation. Lastly, by finding the points of intersection of three frequency contour lines in the small unit, the crack location and depth are identified. In order to verify the effectiveness of the presented method, a multiple cracks identification experiment is carried out. The diagnostic tests on a cantilever beam under two working conditions show the accuracy of the proposed method: with a maximum error of crack location identification 2.7% and of depth identification 5.2%. The method is able to detect multiple crack of beam with less subdivision and higher precision, and can be developed as a multiple crack detection approach for complicated structures. 展开更多
关键词 multiple cracks structure three steps meshing
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TWO STEPS CHEMICAL-MECHANICAL POLISHING OF RIGID DISK SUBSTRATE TO GET ATOM-SCALE PLANARIZATION SURFACE 被引量:11
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作者 LEI Hong LUO Jianbin LU Xinchun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期496-499,共4页
In order to get atomic smooth rigid disk substrate surface, ultra-fined alumina slurry and nanometer silica slurry are prepared, and two steps chemical-mechanical polishing (CMP) of rigid disk substrate in the two s... In order to get atomic smooth rigid disk substrate surface, ultra-fined alumina slurry and nanometer silica slurry are prepared, and two steps chemical-mechanical polishing (CMP) of rigid disk substrate in the two slurries are studied. The results show that, during the first step CMP in the alumina slurry, a high material removal rate is reached, and the average roughness (Ra) and the average waviness (Wa) of the polished surfaces can be decreased from previous 1.4 nm and 1.6 nm to about 0.6 nm and 0.7 nm, respectively. By using the nanometer silica slurry and optimized polishing process parameters in the second step CMP, the Ra and the Wa of the polished surfaces can be further reduced to 0.038 nm and 0.06 am, respectively. Atom force microscopy (AFM) analysis shows that the final polished surfaces are ultra-smooth without micro-defects. 展开更多
关键词 TWo steps Chemical-mechanical polishing(CMP) Rigid disk substrateAtom-scale planarization Slurry
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“Ten Steps”法在污水处理厂设备管理中的应用 被引量:1
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作者 高勇 蔡芝斌 +2 位作者 许华英 邹华 徐建祥 《环境科学与管理》 CAS 2011年第5期112-114,共3页
污水处理厂设备管理具有相应的特点,结合多年的污水处理厂设备管理经验,从设备的选、用、养、修等诸多环节进行讨论,总结了设备管理"Ten Steps"法,为行业设备管理提供相应借鉴。
关键词 污水处理厂 设备管理 环节 TEN steps 借鉴
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“Final all possible steps”approach for accelerating stochastic simulation of coupled chemical reactions 被引量:1
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作者 周文 彭新俊 +2 位作者 刘祥 闫正楼 王翼飞 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第3期379-387,共9页
In this paper, we develop a modified accelerated stochastic simulation method for chemically reacting systems, called the "final all possible steps" (FAPS) method, which obtains the reliable statistics of all spec... In this paper, we develop a modified accelerated stochastic simulation method for chemically reacting systems, called the "final all possible steps" (FAPS) method, which obtains the reliable statistics of all species in any time during the time course with fewer simulation times. Moreover, the FAPS method can be incorporated into the leap methods, which makes the simulation of larger systems more efficient. Numerical results indicate that the proposed methods can be applied to a wide range of chemically reacting systems with a high-precision level and obtain a significant improvement on efficiency over the existing methods. 展开更多
关键词 "final all possible steps approach stochastic simulation algorithm chemically reacting systems
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Cognitive Translation:On UT and Translation Steps from the Perspective of Cognitive Psychology
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作者 刘雪 《海外英语》 2010年第5X期197-197,共1页
The unit of translation(UT thereafter) is a significant and controversial issue in the study of translation theories and practice.It is generally acknowledged that the UT is dynamic rather than static,and translator&#... The unit of translation(UT thereafter) is a significant and controversial issue in the study of translation theories and practice.It is generally acknowledged that the UT is dynamic rather than static,and translator's cognitive role is of great account.This thesis has been devoted to a brief glimpse of the UT from the perspective of cognitive psychology,and proposes the operable translation steps. 展开更多
关键词 COGNITIVE TRANSLATION unit of TRANSLATION TRANSLATION steps
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