共查询到20条相似文献，搜索用时 796 毫秒
1.
文章针对PLC控制系统中T、C、D软元件数据常频繁改变的特点,介绍了一种利用变址寄存器V预先设定T(C或者D)的软元件序号,并根据设定的序号、改变用户程序中的T(C或者D)的设定值并显示. 相似文献
2.
运用博弈论研究了原制造商（OEM）和独立再制造商（IR）的R&D研发模式和溢出效应对再制造闭环供应链的影响.建立并求解了NC、 C、 V以及CV等4种R&D研发模式,并用比较分析和数值仿真对结果进行了探讨.研究表明：OEM和IR的R&D投资额和社会福利均在CV模式下最高,C模式和V模式次之,NC模式下最低;不同R&D模式下供应链成员的利润差异受废旧品回收率、溢出率和R&D成本的影响;废旧品回收率的增大不仅会提升IR的R&D投资额,增大供应链成员的利润,也会改变供应链成员以及整个社会的R&D模式偏好. 相似文献
3.
4.
5.
设计以STC89C52单片机核心来设计温湿度控制系统,分为两个部分,一个是上位机,另一个是下位机（单片机）。系统具有显示温湿度、设定温湿度上下限值并保存设定的上下限值的功能,且能自动控制环境的温湿度参数。 相似文献
6.
掌握省际研发（R&D）资本存量水平及其时空动态演化特征，对于准确理解区域科技创新水平和落实区域创新驱动发展战略意义重大。本文遵循SNA2008的R&D资本核算原则，运用综合永续盘存法，测算出1998-2018年中国31个省份R&D的资本存量总额（K）、资本存量净额（Kn）和生产性资本存量（Kp），并对这三种指标进行比较检验和空间动态分析。研究发现：样本期间，我国R&D资本存量保持年均15.58%的稳步增长，东部地区R&D资本存量显著高于中部、西部和东北地区之和；相较于K和Kn，使用Kp作为研发投入指标更能体现区域R&D水平；省际R&D资本存量的空间分布不均衡状态明显，呈现出“高-高”水平和“低-低”水平的正向空间集聚特征，并且在样本期间这种特征没有得到根本性的改变。据此，本文提出了优化省际R&D资本存量空间布局、推动区域间研发活动合作的几点对策建议。 相似文献
7.
8.
机床的直线轴通常设置有软限位（参数设定限位）和硬限位（行程开关限位）两道保护“防线”，限位问题是数控机床常见故障之一，就导致“限位报警”的主要原因作一些分析和说明。 相似文献
9.
由于机床数控系统种类繁多、设备形态结构各异、设计方式多种多样、故障现象千差万别,维护好数控设备是具有相当难度的工作。在掌握了机械结构及电气控制原理的同时,必须合理分析,灵活运用,善于总结才能起到事半功倍的收效。立足于原理,由易到难地去缩小故障范围并排除。为了保障机床地运行安全,机床的直线轴通常设置有软限位（参数设定限位）和硬限位（行程开关限位）两道保护“防线”。 相似文献
10.
目的:观察右美托咪定防治经尿道前列腺电切术患者寒颤的临床效果。方法:选择择期在腰硬联合麻醉下经尿道前列腺电切术(TURP)的患者69例,随机分为右美托咪定组(D组)、曲马多组(T组)、对照组(C组),每组23人。D组静脉泵注右美托咪定负荷量0.5μg·kg~(-1),随后以0.2~0.3μg·kg~(-1)·h-1维持泵注至手术结束前0.5 h;T组静脉注射曲马多负荷量0.6 mg·kg~(-1),随后以1 mg·kg~(-1)泵注至手术结束前0.5 h;C组给予等量的生理盐水泵注。记录麻醉前(T1)、手术开始后45 min(T2)、术毕(T3)患者的体温和镇静状态评分;记录寒颤评级和恶心呕吐等情况。结果:三组组间对应时点的体温无差异(P0.05),T2和T3的体温均低于T1(P0.05);D组和T组的镇静评分高于C组(P0.05);D组和T组的寒颤发生率低于C组(P0.05);T组恶心呕吐的发生率高于D组和C组(P0.05)。结论:右美托咪定可以防治经尿道前列腺电切术患者的寒颤,比曲马多更有优越性。 相似文献
11.
12.
生物制药作为一种高技术含量的知识密集型产业,专利申请对于新药研发显得尤为重要。从投入产出网络分析方法出发,通过测算专利技术群的技术感应力系数和技术影响力系数,以此来识别核心技术和前沿技术;然后运用动态投入产出模型,对各个技术群专利量的演化趋势进行预测。研究结果表明,IPC为C12N的技术群是生物制药技术网络中的前沿技术群和核心技术群,并预测出该技术群的专利量在未来几年的演化趋势。 相似文献
13.
R. Dhananjayan T. Malati Y. Rupasree Vijay Kumar Kutala 《Indian journal of clinical biochemistry : IJCB》2015,30(3):263-270
The present work was aimed to study the association of one carbon genetic variants, hyperhomocysteinemia and oxidative stress markers, i.e., serum nitrite, plasma malondialdehyde (MDA) and glutathione (GSH) on intimal medial thickening (IMT) in patients with type 2 diabetes mellitus (T2D). A total number of 76 subjects from ACS Medical College and Hospital, Chennai, India were included in the study, i.e., Group I (n = 42) of T2D and Group II (n = 34) of age- and sex matched healthy controls. The glycated haemoglobin was measured by ion-exchange resin method; plasma homocysteine by Enzyme Linked Immunosorbant Assay method; serum nitrite (nitric oxide, NO), plasma MDA and GSH by spectrophotometric methods; the IMT by high frequency ultrasound. The polymorphisms of one carbon genetic variants were genotyped using polymerase chain reaction-restriction fragment length polymorphism and amplified fragment length polymorphism methods. Results indicate that methyltetrahydrofolate homocysteine methyl transferase (MTR) A2756G allele was found to be protective in T2D and the other variants were not significantly associated with T2D. Glutamate carboxypeptidase II (GCP II) C1561T (r = 0.34; p = 0.05) and methylene tetrahydrofolate reductase (MTHFR) C677T (r = 0.35; 0.04) showed positive correlation with plasma homocysteine in T2D cases. In this study, MTR A2756G allele was found to be protective in T2D; GCP II C1561T and MTHFR C677T showed positive association with plasma homocysteine in T2D cases. Among all the genetic variants, MTR A2756G was found influence IMT. RFC 1 G80A and TYMS 5′-UTR 2R3R showed synergistically interact with MTR A2756G in influencing increase in IMT. 相似文献
14.
将异枝竹属Metasasa W．T. Lin作为酸竹属Acidosasa C．D．Chu et C．S．Chao ex Keng f．的异名处
理。异枝竹Metasasa carinata W．T. Lin和白环异枝竹 Metasasa albo-farinosa W．T．Lin作为新组合名Aci-dosasa nanunica(McCl．)C．S．Chao et G．Y．Yang，comb．nov．的异名。 相似文献
15.
为解决基于分类号或财产号随书光盘存取管理模式所存在的随书光盘难排架、难查询、难定位的问题,提出一种基于随书光盘工作流水号的存取模式,并采用数据库和Flash图形动画等技术,实现具有数据录入、记录查询和Flash图形动画定位等功能的可视化随书光盘存取管理系统。 相似文献
16.
Ramesh Chander Kavita Singh A K Khanna S M Kaul Anju Puri Rashmi Saxena Gitika Bhatia Farhan Rizvi A K. Rastogi 《Indian journal of clinical biochemistry : IJCB》2004,19(2):141-148
Terminalia arjuna (T. arjuna) stem bark was successively extracted with petroleum ether (A), solvent ether (B), ethanol (C) and water (D). The lipid lowering
activity of these four fractions A, B, C, and D was evaluatedin vivo in two models viz., triton WR-1339 induced hyperlipemia in rats as well as fructose rich high fat diet (HFD) fed diabetic-
dyslipidemic hamsters. Hyperlipidemia induced by triton caused marked increase in the plasma levels of total cholesterol (Tc),
triglyceride (Tg) and phospholipids (PL) in rats. After treament withT. arjuna fractions A, B, C, and D at the doses of 250 mg/kg per oral (p.o.),only the ethanolic fraction (C) exerted significant lipid
lowering effect as assessed by reversal of plasma levels of Tc, Tg and PL in hyperlipidemic rats. In another experiment, feeding
with HFD produced marked dyslipidemia as observed by increased levels of plasma Tc, Tg, glucose (Glu), glycerol (Gly) and
free fatty acids (FFA) in hamsters. After treatment withT. arjuna fractions at the doses of 250 mg/kg p.o. only two fraction (B and C) could exert significant lowering in the plasma levels
of lipids and Glu. in dyslipidemic hamsters.In vitro experimentT. arjuna fractions at tested concentrations (50–500 μg/ml) inhibited the oxidative degradation of lipids in human low density lipoprotein
and rat liver microsomes induced by metal ions. These fractions when tested against generation of oxygen free radicals at
the concentrations (50–500 μg/ml), counteracted the formation of superoxide anions (O−2) and hydrodyl radicals (OH) in non enzymic test systems. The efficacy ofT. arjuna fractions as antidyslipidemic and antioxidant agents was found, fraction C> fraction B> fraction A. 相似文献
17.
We examined the performance of three microfluidic devices for stretching DNA. The first device is a microchannel with a contraction, and the remaining two are the modifications to the first. The modified designs were made with the help of computer simulations [C. C. Hsieh and T. H. Lin, Biomicrofluidics 5(4), 044106 (2011) and C. C. Hsieh, T. H. Lin, and C. D. Huang, Biomicrofluidics 6, 044105 (2012)] and they were optimized for operating with electric field. In our experiments, we first used DC electric field to stretch DNA. However, the experimental results were not even in qualitative agreement with our simulations. More detailed investigation revealed that DNA molecules adopt a globular conformation in high DC field and therefore become more difficult to stretch. Owing to the similarity between flow field and electric field, we turned to use flow field to stretch DNA with the same devices. The evolution patterns of DNA conformation in flow field were found qualitatively the same as our prediction based on electric field. We analyzed the maximum values, the evolution and the distributions of DNA extension at different Deborah number in each device. We found that the shear and the hydrodynamic interaction have significant influence on the performance of the devices. 相似文献
18.
陶德定 《中国科学院研究生院学报》1994,32(4):369-369
A revision is made of the species Walsura xizangensis C. Y. Wu et H. Li found
in Xizang. A new combination, Glycosmis xizangensis (C. Y. Wu et H. Li)D. D. Tao, is made. 相似文献
19.
技术集成的实证研究——以Iansiti对美日半导体行业的研究为例 总被引：7，自引：0，他引：7
“技术集成”是产品开发过程中企业对多种技术选项进行评估和选择的过程。本文以美日半导体行业为对象,介绍了对技术集成阶段与绩效的关系,技术集成方式与绩效的关系所做的实证研究。研究表明:技术集成与半导体产业研发活动的绩效有着非常显著的相关性;技术集成方式有渐进式和革命式之分,具体选择应依据企业所处的环境而定。我国半导体产业仍处于技术追赶阶段,宜采用以渐进式为主的技术集成方式。 相似文献
20.
Industrial research and development (R&D) is a set of activities within the broader set of decisions and activities: the process of technological innovation (TI). It is technology transfer (commercialization of the innovation) that leads to technology diffusion that permits production and employment expansion and hence economic growth — an important goal of industrial policy. Firms' managements and government policy- makers should recognize the close relationships among the phases of TI and direct their policy, planning, budgeting and control decisions to the complete process. Many policies currently focus their attention to only one or a few points (such as R&D).In this study we conducted a detailed cost analysis of a limited number of innovation projects and studied the distributions of TI cost over the process phases. We find that almost half of TI costs are devoted to R&D, which implies that government support of this phase is important. Different cost patterns emerge when we classify innovations by industrial sectors, firms' sizes and project complexity. Complex innovations require larger and more variable (risky) R&D budgets. Smaller firms need more assistance in technology transfer. These are only a few important policy implications. This study emphasizes the importance of post-R&D phases and concludes that differential industrial policy may be required for technological innovations. 相似文献