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511.
Jiunn-Liang Guo Gin-Shuh Liang Kung-Don Ye Younger Wu 《Maritime Policy and Management》2007,34(1):21-36
Nowhere else in the world are there marine transportations highly confined than across the Taiwan Straits (mainland China and Taiwan). This study strives to explore the present employment status of Taiwanese ship officers under the influence of special shipping across the Taiwan Straits, and to make sure if such an employment trend has a negative impact on the future operating mode of Taiwan shipping companies. By means of field interview and questionnaire, this study collected the employment data of ship officers from 21 leading shipping companies in Taiwan, and made a statistical analysis. The research findings show that the existing cross-strait shipping relationship, which is seriously distorted by the hostility between the governments of Taiwan and mainland China across the Taiwan Straits, has made Taiwanese shipping companies turn to flagging-out in order to enter the extensive shipping market of mainland China. This leads to a decline of job opportunities for Taiwanese ship officers. Ironically, the ship officers from mainland China pose a biggest threat to those in Taiwan in this respect. In addition, the operating modes of Taiwanese shipping companies also change gradually in tune with the increasing number of non-Taiwanese ship officers (mainly those from mainland China). 相似文献
512.
LIU Peter Xiao-ping 《船舶与海洋工程学报》2002,1(2):46-50
An Internet-based teleoperation platform for Mobile Robot is introduced in this paper. The hardware of the system mainly consists of a mobile robot. Its software employs client-server architecture for robot control and feedback information display . Different communication protocols are adopted according to the characteristics of message exchanged between the robot server and the client. The user interface is designed for the purpose of interaction. The great benefit of this client-server architecture is that the client software is insulated from the lowest level details of the mobile robot. Thus, it is very easy to implement and test new advanced teleoperation control algorithms, interface designs and applications on this platform without large programming work. 相似文献
513.
用放射免疫法对妊娠16~28周179例孕妇血清、羊水及胎血进行甲胎蛋白(alphafetoprotein,AFP)、人绒毛膜促性腺激素β亚基(freebetasubunitofhumanchorionicgonadotropin,β-HCG)及游离雌三醇(unconjugatedoestriol,uE3)的联合检测发现:正常孕妇血清和羊水、胎儿血清中AFP、β-HCG和uE3均呈正相关。无脑儿、羊水过少及胎死宫内母血清AFP升高,分别为5.20MOM、5.77MOM和14.03MOM,β-HCG和μE3为低值;胎儿染色体异常──21三体、14三体嵌合体,β-HCG值在羊水、母血清和胎儿血清中明显升高,分别为3.84MOM、2.65MOM和1.75MOM,而AFP和uE3水平降低,提示联合检测妊娠中期母血清中的AFP、β-HCG和uE3值,不仅可作为产前筛查胎儿染色体异常、神经管缺陷的指标,同时可预示胎儿高危状态和围产儿死亡。 相似文献
514.
用数值模拟方法对旁通增压系统的动态性能作了研究,着重考察了旁通阀以不同规律启闭时增压系统各主要参数的响应情况,探讨了当柴油机负荷突变时由于旁通阀响应滞后而可能出现的问题。本文的研究助于揭示该增压系统的动态特性,为柴油机的优化控制系统设计提供了依据。 相似文献
515.
现阶段,我们对综合运输的理解是:综合运输是一种至少包括两种以上运输方式,并在基础设施、技术标准、政策法规、通讯信息和管理体制等方面,实现了全面整合的长途、全程、无缝、连续的运输过程。从发展过程来看,可分成传统综合运输发展阶段和现代综合运输发展阶段。 在传统综合运输发展时期,各种运输方式的运输能力,特别是它们各自的基础设施能力,都分别得到较充分的发展,各种运输方式的经济、 相似文献
516.
站修移动式成套钩缓装置拆装机是铁道部运输局装备部提出的站修应配备的10项主要修车装备之一。从2001年开始,天津铁路分局科委组织了拆装机的研制工作,完成了从一代机到二代机的过渡,并且在拆装机的设计、制造等方面积累了一定的经验。 相似文献
517.
粉喷桩与土工格栅相结合方案处理天汊路改建工程中舜时滑塌段软土路基,具有工艺简单,工期短,工后沉降小,提高地基承载力见效快的特点,是快速处理局部软土路基,确保工程质量和进度简便易行的方法。 相似文献
518.
519.
The effects of a moving gate on dam break flow experiments are numerically considered in this paper. The dam break flow process is modelled by a sudden gate release. A Constrained Interpolation Profile (CIP)-based model is employed to solve the Navier-Stokes equations with the free surface boundary condition to deal with the water-air-gate interactions. In addition, the VOF-type THINC/SW method is used to capture the free surface. The movable gate is simulated by an immersed boundary, and a gate motion formula is proposed from existing experimental data and applied in the dam break flow computations. The difference between the water profile and pressure domain with/without gate motion is examined. The dam breaks with different gate motions are discussed as well. The numerical results show that the proposed gate motion formula correlates well with the numerical modelling, and the gate motion has a significant influence in the water collapse process and cannot be neglected in the study of dam break. 相似文献
520.
Objective To evaluate the methylation status at CpG site -55 in the interferon-gamma (IFN-7) gene promoter and its effect on IFN-7 expression in chronic hepatitis B. Method The authors recruited 30 patients with UBeAg-positive chronic hepatitis B (CHB), 30 HBeAg-negative CHB patients, and 30 healthy blood donors. Pyrosequeneing was used to determine the methylation status at CpG site -55 in the IFN-γ gene promoter following bisulfite treatment of DNA in peripheral blood mononuclear cells (PBMCs). The expression of IFN-γ was analyzed by real-time RT-PCR and ELISA. HBV DNA in PBMCs was detected by nested PCR. Results The methylation level at CpG site -55 in the IFN-γ gene promoter was significantly increased, resulting in subsequent down-regulation of the expression of this cytoldne in CHB. The methylation level at CpG site -55 was significantly higher in HBeAg-positive patients than in HBeAg-negative ones (P<0.01) and was also significantly higher in PBMCs from HBV DNA-positive patients than from HBV DNA-negative ones (P<0.01) ; the methylation level at CpG site -55 was positively correlated with the amount of HBV DNA in serum (P<0.01). Oonclusion IFN-γ gene expression appears to be regulated by methylation of the IFN-γ gene promoter in CHB; the methylation level at CpG site -55 is associated with HBV infection. 相似文献