我国低碳航运产业价值链的结构乘数效应     

甘爱平  詹凌晨  真虹  张婕姝 《上海海事大学学报》2016,37(3):47-51

针对航运低碳投资支出巨大的问题，运用结构性乘数，对我国用于低碳航运产业价值链中的支出产生的乘数效应进行研究.由两部门计算的简单投资乘数为1.547 7，由四部门计算的投资乘数均值为1.293 1.从长期看，乘数效应反映出航运低碳产业的投资收益大于投资支出，对航运业低碳减排具有现实和经济意义.  相似文献   

自动化集装箱码头自动导引小车与轨道式龙门起重机的协同调度     

杨勇生  冯有勇  梁承姬  许波桅  李军军 《上海海事大学学报》2017,38(2):1-6

为解决自动导引小车(Automated Guided Vehicle,AGV)与轨道式龙门起重机(Rail-Mounted Gantry Crane,RMG)的协同调度问题,考虑AGV和RMG的任务分配约束,以卸船作业最小完工时间为目标,建立混合整数规划(Mixed Integer Programming,MIP)模型.改变AGV,岸桥和箱区数量的配置,得出不同条件下的完工时间.对该问题设计两组算例:小规模算例采用CPLEX软件和遗传算法(Genetic Algorithm,GA)分别进行求解,通过结果对比验证GA的有效性;大规模算例采用GA求解,给出自动化码头设备调度优化方案.分析结果表明,卸船完工时间随着卸船任务量的增加而增加,随着AGV,岸桥和箱区数量的增加而减少,且AGV和岸桥数量的增加对完工时间的影响大于箱区数量的增加时完工数量的影响.  相似文献   

Kinematic analysis of the drag flick in field hockey     

Rony Ibrahim  Gert S. Faber  Jaap H. van Dieën 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(1):45-57

Attaining high speed of the stick head and consequently of the ball is essential for successful performance of the drag flick in field hockey, but the coordination pattern used to maximise stick head speed is unknown. The kinematics of the drag flick was studied in ten elite hockey players who performed twenty shots each towards a target located 1.5 m high. A 150 Hz active marker motion analysis system was used, alongside two force plates to detect foot touchdown. Angular velocity and contribution to stick endpoint speed of upper body joints were analysed. Repeated measures ANOVA was used to compare timing of onset and peak angular velocities between joints. Participants used a kinematic pattern that was close to a proximal-to-distal sequence. Trunk axial rotation and lateral rotation towards the target, right wrist flexion and left wrist extension were the main contributors to stick endpoint speed. Coaches should emphasise trunk rotations and wrist flexion and extension movements for maximising stick head speed. Given the high level of the participants in this study, the coordination of joints motions, as reported here, can serve as a guideline for drag flick training.  相似文献   

预制语块与大学英语作文教学   总被引：1，自引：0，他引：1  

卢中 《阿坝师范高等专科学校学报》2006,23(1):115-117

通过预制语块的研究成果,从二语习得的角度,论述了预制语块在英语作文教学中的三个优势。利用预制语块进行作文教学,教师要转变教学观念,传授语块学习的知识和策略,鼓励学生“死记硬背”,以及增加语块输出机会,这样才能为大学英语作文教学找到新的思路。  相似文献   

档案馆信息生态链涵义、结构与类型探析     

康蠡  田彬 《北京档案》2016,(6):10-13

本文在定义档案馆信息生态链的基础上阐述其内涵,认为档案馆信息生态链包含信息人、信息和链接三个基本要素。其主要的结构形态是多链星型结构和多链网状结构。按照不同的分类标准,档案馆信息生态链又可以划分为多种类型。  相似文献   

Hip and upper extremity kinematics in youth baseball pitchers     

Taylor Holt 《Journal of sports sciences》2016,34(9):856-861

The purpose of this study was to examine the relationship between dynamic hip rotational range of motion and upper extremity kinematics during baseball pitching. Thirty-one youth baseball pitchers (10.87 ± 0.92 years; 150.03 ± 5.48 cm; 44.83 ± 8.04 kg) participated. A strong correlation was found between stance hip rotation and scapular upward rotation at maximum shoulder external rotation (r = 0.531, P = 0.002) and at ball release (r = 0.536, P = 0.002). No statistically significant correlations were found between dynamic hip rotational range of motion and passive hip range of motion. Hip range of motion deficits can constrain pelvis rotation and limit energy generation in the lower extremities. Shoulder pathomechanics can then develop as greater responsibility is placed on the shoulder to generate the energy lost from the proximal segments, increasing risk of upper extremity injury. Additionally, it appears that passive seated measurements of hip range of motion may not accurately reflect the dynamic range of motion of the hips through the progression of the pitch cycle.  相似文献   

中外女排比赛接拦回球效果及失误原因的比较分析     

李华燕 《湖北体育科技》2016,(11):1001-1004

中外女排比赛中接拦回球数量仍然较多,占扣球总数的14%左右,比赛中80%左右的拦回球落在3m线前区域。中国女排接拦回球的效果好于日本女排、塞尔维亚女排和多米尼加女排,但与巴西女排、美国女排相比差距较大,同俄罗斯女排、意大利女排接拦回球的效果相差不大。接拦回球失误的主要原因有接拦回球队员反应跟不上造成无防守动作形成失误,其次是接拦回球队员防守意识不强未及时进入防守位置形成失误。中国女排应加强接拦回球跟进保护意识培养,努力提高各种倒地和单手垫球技术,从而提高接拦回球能力。  相似文献   

加工柴油机机体大进给量高速强力铣削专用夹具的应用研究     

蔡红军  段华荣  王林军 《河南广播电视大学学报》2003,16(2):78-80

通过对加工柴油机机体(两侧面)强力高效铣削专用夹具的应用研究，不仅从根本上解决了机体两侧面加工长期存在的扭曲变形难题，而且还对在大进给量高速强力铣削的加工状态下，如何提高夹具的适应能力进行了有益的探索，并取得了明显的效果。  相似文献   

亚硝酸盐及其相关物种的环境暴露与生理功能     

童晓滨 《南平师专学报》2006,25(2):20-24

本文对亚硝酸盐及其相关物种的产生来源及其人在其中的暴露环境进行了剖析,认为有内源性与外源性双重作用,并具有各自的规律,而内源性与外源性的结合是危险因素,并对其暴露结果及其阻断进行了讨论。  相似文献   

英国超市消费现象分析及其启示     

宋涛 《新乡师范高等专科学校学报》2002,16(1):47-48

英国超市消费逐年增长 ,其经营方式更加灵活 ,销售领域更加广泛。中国是一个人口大国 ,随着居民收入水平的不断提高 ,消费水平也必然不断提高 ,如何使我国超市消费成为新的消费热点 ,引导超市经营向良性发展 ,我们可以透过英国超市消费现象 ,得到很好的启迪  相似文献