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21.
Sensors, mounted on the dexterous end of a robot, can be used for feedback control or calibration. When you mount a sensor on a robot it becomes necessary to find the pose (orientation and position) of the sensor relative to the robot. This is the sensor registration problem. Many researchers have provided closed-form solutions to the sensor registration problem; however, the published solutions apply only to sensors that can measure a complete pose (three positions and three orientations). Many sensors, however, can provide only position information; they cannot measure the orientation of an object. This article provides a closed-form solution to the sensor registration problem applicable when: (1) the sensor can provide only position information and (2) the robot can move along and rotate about straight lines. © 1994 John Wiley & Sons, Inc. 相似文献
22.
同志们,今天我们在这里隆重召开2005年度科技工作总结表彰大会,会议开得非常好。梁铁总工程师作的2005年度科技工作报告,总结了去年的科技工作,布置了今年的科技工作,这是对广大科技工作人员过去工作的肯定和今后工作的展望。我们还表彰了一批科技工作先进个人、先进集体和先进单位,并聘任了第三批技术专家和第四批学科带头人,这说明柳钢的科技工作是欣欣向荣的。 相似文献
23.
国内核电厂吸取福岛事故的经验教训,增加了严重事故后应急补水设施,完善了应急补水的相关功能,进一步提高了核电厂的安全水平.对M 310核电机组严重事故状态下的应急补水设施进行技术分析,分析计算结果表明,应急水源到应急补水泵接入点距离过长,水损过大,实际补水压力及流量无法满足设计要求.针对该问题提出一系列设计改进措施,优化改进后的应急补水设施可保证严重事故工况下M 310核电机组应急补水设施的可用性,从而进一步提高核电机组的安全性. 相似文献
24.
Shuya Liang Miaomiao Wang Jun Wang Guanzhi Chen 《Chembiochem : a European journal of chemical biology》2021,22(22):3184-3189
To overcome high toxicity, low bioavailability and poor water solubility of chemotherapeutics, a variety of drug carriers have been designed. However, most carriers are severely limited by low drug loading capacity and adverse side effects. Here, a new type of metal-drug nanoparticles (MDNs) was designed and synthesized. The MDNs self-assembled with Fe(III) ions and drug molecules through coordination, resulting in nanoparticles with high drug loading. To assist systemic delivery and prolong circulation time, the obtained MDNs were camouflaged with red blood cell (RBCs) membranes (RBCs@Fe-DOX MDNs) to improve their stability and dispersity. The RBCs@Fe-DOX MDNs presented pH-responsive release functionalities, resulting in drug release accelerated in acidic tumor microenvironments. The outstanding in vitro and in vivo antitumor therapeutic outcome was realized by RBCs@Fe-DOX MDNs. This study provides an innovative design guideline for chemotherapy and demonstrates the great capacity of nanomaterials in anticancer treatments. 相似文献
25.
电感电容损耗电阻的讨论 总被引:3,自引:0,他引:3
通过对电容电感阻抗的测量,发现实验值偏离理论值。定性地分析了误差的来源,得出的结论是电感电容内部的损耗电阻随着频率的变化而变化,变化方向相反而并非相同。 相似文献
26.
针对磷酸二铵(DAP)产品养分波动大、含水量偏高、易结块、颜色变化大等缺点,在生产过程中采取了相应的解决措施,如配矿、联产、设备改造、工艺指标调整等,使DAP装置不仅保持了原有的优点,而且产品质量问题也得到了有效解决。养分基本保持在64.0%~64.6%,水分下降到2.1%~2.2%,结块现象较少,颜色也比较统一。 相似文献
27.
Effect of additives on formation of natural gas hydrate 总被引:1,自引:0,他引:1
The formation of natural gas hydrate (NGH) is studied in this work. Kinetics data of hydrate formation with no agitation were collected at various concentrations of the aqueous solutions with different additives such as alkylpolyglucside, sodium dodecyl benzene sulfonate and potassium oxalate monohydrate. Various kinds of additive increased the formation rates of NGH and its storage capacity and reduced the induction time of NGH formation. Moreover, the storage capacity, the induction time and the hydrate formation rate were influenced by the concentration of the aqueous solution. 相似文献
28.
Rui-Hong Liang Xian-Lin Dong Ying Chen Fei Cao Yong-Ling Wang 《Journal of the American Ceramic Society》2006,89(10):3273-3276
Ba0.55 Sr0.45 TiO3 /MgO composites were successfully prepared by the heterogeneous precipitation method and their structural, surface morphological, tunable properties, and dielectric properties at microwave frequency were systemically investigated. Compared with the sample prepared by the traditional solid-state method, the sample prepared by the heterogeneous precipitation method exhibits a smaller grain size, more uniform microstructure, higher tunability, and lower microwave loss, and these properties are very beneficial to the development of the microwave tunable devices application. Moreover, the effects of La2 O3 doping on the dielectric and tunable properties of BST/MgO composites are investigated. The result shows that the La3+ -doped sample has higher tunability and lower microwave loss than the undoped one. 相似文献
29.
In this paper, we will extend the strict maximum principle preserving flux limiting technique developed for one dimensional scalar hyperbolic conservation laws to the two-dimensional scalar problems. The parametrized flux limiters and their determination from decoupling maximum principle preserving constraint is presented in a compact way for two-dimensional problems. With the compact fashion that the decoupling is carried out, the technique can be easily applied to high order finite difference and finite volume schemes for multi-dimensional scalar hyperbolic problems. For the two-dimensional problem, the successively defined flux limiters are developed for the multi-stage total-variation-diminishing Runge–Kutta time-discretization to improve the efficiency of computation. The high order schemes with successive flux limiters provide high order approximation and maintain strict maximum principle with mild Courant-Friedrichs-Lewy constraint. Two dimensional numerical evidence is given to demonstrate the capability of the proposed approach. 相似文献
30.