检索结果-南通市图书馆

can graphene keep its promise?

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2015年第1期2卷 54-56页

作者： philip Ball philip Ball writes for NSR from London.

Over the past decade,the carbon material known as graphene has been hailed as a‘wonder material’,which might revolutionize everything rom microelectronic circuitry to ultra-strong composite *** displays several striking properties:it conducts electricity,it is transparent,and exceedingly strong and *** will it live up to its promise?

关键词： can graphene keep its promise high very

Synthetic organic chemistry in china: building on an ancient tradition——an interview with Qi-Lin Zhou and Xiaoming Feng

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2017年第3期4卷 437-440页

作者： philip Ball philip Ball writes for NSR from London.

If the core of chemistry is making molecules,then the construction of those found in nature—natural products—has long been regarded as one of the highest forms of the art in *** molecules,produced by living organism... 详细信息

关键词： in Synthetic organic chemistry in china an interview with Qi-Lin Zhou and Xiaoming Feng been that for is of with

Adaptive control of MIMO Mechanical Systems with Unknown Actuator Nonlinearities Based on the Nussbaum Gain Approach

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

IEEE/cAA Journal of Automatica Sinica 2016年第1期3卷 26-34页

作者： ci chen Zhi Liu yun Zhang c.L.philip chen Shengli Xie School of Automation Guangdong University of Technology IEEE Faculty of Science and Technology University of Macao Guangdong Key Laboratory of IoT Information Processing

This paper investigates MIMO mechanical systems with unknown actuator nonlinearities. A novel Nussbaum analysis tool for MIMO systems is established such that unknown time-varying control coefficients are tackled. In contrast to existing literatures on continuous-time systems, the newly-developed Nussbaum tool focuses on extending the traditional Nussbaum result from one dimensional case to the multiple one. Specifically, not only the multiple unknown input coefficients are extended to the time-varying, but also the limitation of the prior knowledge of coefficients' upper and lower bounds is removed. Furthermore, an adaptive robust controller associated with the proposed tool is presented. The asymptotic tracking of MIMO mechanical systems is guaranteed with the help of the Lyapunov Theorem. Finally, a simulation example is provided to examine the validity of the proposed scheme. © 2014 chinese Association of Automation.

关键词： Actuators Adaptive control systems control nonlinearities Mechanical actuators Mechanics MIMO systems Time varying control systems

在线全文

学校读者我要写书评

暂无评论

量子计算的最佳量子比特可能就是原子

世界科学 2024年第5期 26-29页

作者：苦山菲利普·鲍尔《自然》杂志社

在为量子计算机寻找最具可扩展性的硬件的过程中，由单个原子构成的量子比特正在迎来突破性的时刻。2023年年底，科技巨头IBM宣布了一个听起来像是量子计算领域里程碑事件的消息：他们推出了有史以来第一款拥有1000多个量子比特（qubit...

在为量子计算机寻找最具可扩展性的硬件的过程中，由单个原子构成的量子比特正在迎来突破性的时刻。2023年年底，科技巨头IBM宣布了一个听起来像是量子计算领域里程碑事件的消息：他们推出了有史以来第一款拥有1000多个量子比特（qubits，又称量子位）的芯片，名为“秃鹰”。考虑到仅仅在两年前，该公司才刚推出首款拥有100多个量子比特的芯片“鹰”，这似乎表明该领域正在飞速发展。要制造出能解决今天最强大的经典超级计算机也无法解决的有用问题的量子计算机，就需要进一步扩大它们的规模——也许量子比特数要达到数万甚至数十万才行。但这肯定只是一个工程问题，对吧？

关键词：

Sustainability Issues Related to the Engineering Geology of Long Linear Developments

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2011年第2期8卷 321-327页

作者： PAIGE-GREEN philip cSIR Built Environment Pretoria 0001 South Africa

The development of long linear structures such as roads, rail roads, tunnels, canals and pipelines often has unique engineering geology challenges. These include geological modeling, the identification of material strength and support factors, stability and risk issues, material excavation characteristics and the proposal of techniques for overcoming geotechnical problems, which are normally assessed as part of the conventional engineering geological investigation. An additional factor that is becoming increasingly important but is seldom included in investigations is the sustainability of the geotechnical inputs, in contrast to the sustainability of the project which is generally included. Sustainability issues revolve around the non-renewable nature of most construction resources and there is no doubt that the injudicious use of these construction materials and construction water is not sustainable in the long term: it is thus essential that the engineering geo-logical investigation should take cognizance of such issues and be adapted to provide the design engineer with the information that will maximize the sustainability options. This will also require a closer on-going relation-ship between the engineering geologist and the design engineer. This paper highlights significant sustainability issues (note that these differ from conventional environmental issues) and suggests some mitigating solutions. The sustainability issues discussed include primarily material and water usage, with some reference to energy conservation (mostly through alternative material usage and processing techniques and transportation).

关键词： Engineering geology Sustainability Linear structures construction material Water

Sailing Through the Storm: A Strategic Review of cNOOc’s Unocal Acquisition

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2006年第4期3卷 10-14页

作者： chang philip c. Wang Zhen University of calgary Canada china University of Petroleum Beijing 102249 China

cNOOc＇s 2005 attempt to take over Unocal was dubbed by some chinese media as ＂Acquisition of the century＂, as the $18.5 billion bid was the largest-ever overseas acquisition by a chinese company. cNOOc eventually withdrew its offer after chevron joined the bidding war and political sentiment in the U.S. congress became hostile. This paper analyzes the competitive bidding process and provides a strategic review. cNOOc＇s advantages in the acquisition included its international expertise, financing capability, access to the growing chinese market, and its willingness to retain Unocal staff after the merger. The main challenges were corporate governance, especially the understanding of the role of the board and the management of political risk in the U.S. In hindsight a pledge to divest Unocal＇s U.S. assets and not to give any impression of using subsidized loans could have helped deflect some political criticisms. Eventually, the U.S. government published the required energy security study in 2006 and it provided no support to the political concerns of the congress.

关键词： Strategy political risk cNOOc Unocal chevron

HARMONIc OScILLATORS AT RESONANcE,PERTURBED By A NON-LINEAR FRIcTION FORcE

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2014年第4期34卷 1025-1028页

作者： philip KORMAN yi LI Department of Mathematical Sciences University of CincinnatiCincinnati Ohio 45221-0025USA Department of Mathematics and Statistics Wright State UniversityDayton OH 45435USA

This note is an addendum to the results of Lazer and Frederickson [1], and Lazer [4] on periodic oscillations, with linear part at resonance. We show that a small modification of the argument in [4] provides a more ge... 详细信息

关键词： resonance existence of periodic solutions

Standard Monomial Theory of RR Varieties

在线全文

学校读者我要写书评

暂无评论

Algebra colloquium 2015年第3期22卷 395-404页

作者： philip Foth Sang jib Kim cEGEP champlain - St. Lawrence Qudbec GIV 4K2 Canada Department of Mathematics Ewha Womans University Seoul 120-750 Korea

We construct the RR varieties as the fiber products of Bott-Samelson varieties over Richardson varieties. We study their homogeneous coordinate rings and standard monomial theory.

关键词： Bott-Samelson varieties Richardson varieties RR varieties

Male infertility microsurgical training

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2013年第1期15卷 61-66页

作者： Akanksha Mehta philip S Li center for Male Reproductive Medicine and Microsurgery Cornell Institute for Reproductive Medicine Department of Urology Weill Cornell Medical College New York NY10065 USA

Microsurgical training is imperative for urologists and clinical andrologists specializing in male infertility. Success in male infertility microsurgery is heavily dependent on the surgeon＇s microsurgical skills. Laboratory-based practice to enhance microsurgical skills improves the surgeon＇s confidence, and reduces stress and operating time, benefiting both the patient and the surgeon. This review provides guidelines for setting up a microsurgical laboratory to develop and enhance microsurgical skills using synthetic and animal models. The role of emerginE techniaues, such as robotic-assisted microsureerv, is also discussed.

关键词： laboratory male infertility microsurgery training vasoepididymostomy vasovasostomy