A class of mechanically decidable problems beyond Tarski's model

By means of dimension-decreasing method and cell-decomposition,a practical algorithm is proposed to decide the positivity of a certain class of symmetric polynomials,the numbers of whose elements are variable.This is a class of mechanically decidable problems beyond Tarski model.To implement the algorithm,a program nprove written in maple is developed which can decide the positivity of these polynomials rapidly.

Relay,for a better MRE!

After careful consideration,with the consent of Editor-inChief Weiyan Zhang(张维岩)and Editor-in-Chief Ho-kwang Mao(毛河光),I have decided to step down as the Executive Editor-inChief of MRE to focus on my health and research.I will be succeeded by the next Executive Editor-in-Chief,Professor Jinren Sun(孙今人)of the Shanghai Institute of Laser Plasma,China Academy of Engineering Physics,and Professor Hongbo Cai(蔡洪波)of the Institute of Applied Physics and Computational Mathematics in Beijing.With the help of both of these excellent and experienced physicists,I believe that MRE and its community can be raised to a higher level.

90岁励志爷爷喜圆大学梦

主题语境:励志故事篇幅:322词建议用时:6分钟。1 A grandfather named Paul Hocheder has decided to keep his mind moving with a full college experience at 90 years old.2 Paul already earned one degree in 1960,when he graduated from the University of Maryland after serving seven years in the service.But he decided it would help keep him awake and alive if he went back for another round.

My Good Habit

Eating healthy is my good habit.I used to having lots of bad eating habits.For example,I had no breakfast,but ate junk food or drank cola,so I often got sick.To keep fit,I decided to change my bad eating habits.Now,I always have my three meals regularly.I try my best to eat more fresh fruit and green vegetables instead of junk food.I also drink more milk and water.Gradually,I find my body is geting more and more strong.

Spine Decide软件在脊柱外科临床实习教学中的应用

背景:脊柱,因其复杂的结构和其特殊的功能,一直以来是临床教学的难点和重点,如何将现代化软件应用于脊柱外科临床教学是目前研究的热点。目的:探索Spine Decide软件在脊柱外科临床教学中的应用。方法:通过Spine Decide软件,带教教师可以主动引导实习生自己学习脊柱疾病的诊断,设计手术方案,通过实际手术的参与,充分理解脊柱外科疾病的诊疗过程和疾病发生发展过程。结果与结论:学员通过主动的学习以及与Spine Decide软件的积极互动,能够在短时间内系统化、条理化的理解脊柱疾病的发生机理、诊断、治疗以及预后。Spine Decide应用于教学后,实习生的临床思维能力、自学能力等明显提高,学生学习脊柱相关疾病的主动性和积极性显著优于传统教学方法,创新性和探索性也有了突破性的提高,切实提高了教学质量。

A multi-objective fuzzy optimization model for cropping structure and water resources and its method

Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development.

We Never Told Him He Couldn't Do It

My son Joey was born with*club feet1. Doctors assured us that with treatment he would be able to walk normally-but would never run very well. The first three years of his life were spent in surgery casts and braces. By the time he was eight, you wouldn’t know he had a problem when you saw him walk.

阅读理解练与析

Shoppers,crowding into the West End of Londonyesterday for the start of sales,answered demands fromthe police to use public transportation rather than theircars.They also decided not to invite danger,after thebursting of a bomb in the West End on Christmasevening,by not waiting in line outside the shops.“Iwould have been very worried of what they had.”saidMr Harry Weblin,manager of Liberty’s.Last night the police,which operated a big actionincluding special searches outside the main shops,spoke highly of the common sense of the

你对未来感到焦虑吗？

从前有两个村民坐在树下看日落。他们是非常要好的朋友。安静地坐了一会儿,一个人问对方：“我打算买五亩地,（建）一个花园。你觉得怎么样？”另一个人马上说,“别买花园!”第一个人很惊讶。他问：“为什么？”第二个人回答说：“我打算买一只水牛。然后,我的水牛会闯进你的花园,我们将因此打架,产生误解,然后失去我们的友谊。

“桥”的故事

There are many expressions using the word"bridge".So today,let’s talk about the stories of"bridge".英语中有很多表达中使用了"桥"一词,所以今天我们就来说说"桥"的故事吧。A bridge is a structure that provides passage over something—such as a river,train tracks,a highway or a deep,wide opening in the ground.The word"bridge"can also

动词不定式 作用应熟知

<正>动词不定式是英语非谓语动词的一种(另外两种非谓语动词形式分别是-ing分词和-ed分词,因为它们不能在句子中充当谓语,所以叫作非谓语动词),它不仅具有名词的特征,可在句中充当主语、表语、宾语,同时还具有形容词、副词的特征,可在句中充当宾语补足语、定语、状语,也可充当独立成。同时它还形式多样,不仅有一般式、进行式和完成式,还有主动式和被动式,而且具有多种作用。下面我们就对动词不定式的形式和作用进行总结。

Stylistic Characteristics of English Legal Texts

The characteristics of authority and standard in Legal English decide the significance of the translation about legal English texts. This thesis presents the stylistic features of legal English. It is hoped that translators would be able to understand legal English accurately.

民用飞行器仿真模拟与训练方法研究

民用飞行器是指用于非军事目的的飞行器(flight vehicle)。作为一种运人载物的交通工具,特别强调其安全性、经济性和舒适性,广泛应用于交通业、农业、旅游业等越来越多的领域。该文制定了可行、有效、经济的民用飞行器仿真模拟与训练方法,建立了民用飞行器仿真模拟器训练的DECIDE模型,用于提高民用飞行仿真模拟器的训练效果,保证民用飞行器的安全飞行和任务的有效执行。

基于OODA环的海警装备体系作战能力评估

针对海警装备体系作战能力评估问题,引入OODA作战环理论,建立海警作战OODA环模型,并对其进行时效性分析,修正海警装备体系作战能力解析模型,结合典型的海警装备体系案例,应用OODA环评估方法对海警装备体系作战能力进行估算,得出侦察监视要素对海警装备作战效能影响的基本规律。

Epidemic Spreading Model Based on Social Active Degree in Social Networks

In this paper,an improved Susceptible-Infected-Susceptible(SIS) epidemic spreading model is proposed in order to provide a theoretical method to analyze and predict the spreading of diseases.This model is based on the following ideas:in social networks,the contact probability between nodes is decided by their social distances and their active degrees.The contact probability of two indirectly connected nodes is decided by the shortest path between them.Theoretical analysis and simulation experiment were conducted to evaluate the performance of this improved model.Because the proposed model is independent of the network structure,simulation experiments were done in several kinds of networks,namely the ER network,the random regular network,the WS small world network,and the BA scale-free network,in order to study the influences of certain factors have on the epidemic spreading,such as the social contact active degree,the network structure,the average degree,etc.This improved model provides an idea for studying the spreading rule of computer virus,attitudes,fashion styles and public opinions in social networks.

The Social Support System to be Expanded in 2005 Remarks by NPFPC Vice Minister Pan Guiyu at a Press Conference

At the beginning of 2004, the Chinese government decided to introduce the System of Social Support for Some Rural Families Practicing Family Planning ("social support system"). The General Office of the State Council introduced the proposed program of the National Population and Family Planning Commission (NPFPC) and Ministry of Finance (MOF) on implementing the pilot project of the social support system ("Pilot

Using Multiple Satellites to Search for Maritime Moving Targets Based on Reinforcement Learning

Searching for maritime moving targets using satellites is an attracting but rather difficult problem due to the satellites' orbits and discontinuous visible time windows.From a long term cyclic view,a non-myopic method based on reinforcement learning(RL)for multi-pass multi-targets searching was proposed.It learnt system behaviors step by step from each observation which resulted in a dynamic progressive way.Then it decided and adjusted optimal actions in each observation opportunity.System states were indicated by expected information gain.Neural networks algorithm was used to approximate parameters of control policy.Simulation results show that our approach with sufficient training performs significantly better than other myopic approaches which make local optimal decisions for each individual observation opportunity.

visit with是什么意思?

【问】[389]在美国朋友来信中,常有visit with这个用语。例如: 1.We decided to come to North Carolina and visitwith our son for 6 weeks. 2.We are talking about the possibility of takinganother trip to Ningbo while we’re there to visit with you.

不带to的动词不定式

现代英语中,动词不定式是以动词原形前加虚词to为标志的,但不带to动词不定式(bare infinitive)也很常见,现将常用语法书尚未专门论述的几种情况介绍如下。

精心设计的婚姻骗局

Jeff Peters and Andy Tucker could never be trusted.One day,the two men decided to open a marriage business to make some quick and easy money.The first thingthey did was to fix up an advertisement to be published in newspapers.Their advertisement read like this：