Tensile force correction calculation method for prestressed construction of tension structures

Factors such as errors during the fabrication or construction of structural components and errors of calculation assumption or calculation methods, are very likely to cause serious deviation of many strings＇ actual prestressing forces from the designed values during tension structure construction or service period, and further to threaten the safety and reliability of the structure. Aiming at relatively large errors of the prestressing force of strings in a tension structure construction or service period, this paper proposes a new finite element method （FEM）, the ＂tensile force correction calculation method＂. Based on the measured prestressing forces of the strings, this new method applies the structure from the zero prestressing force status approach to the measured prestressing force status for the first phase, and from the measured prestressing force status approach to the designed prestressing force status for the second phase. The construction tensile force correction value for each string can be obtained by multi-iteration with FEM. Using the results of calculation, the strings＇ tensile force correction by group and in batch will be methodic, simple and accurate. This new calculation method can be applied to the prestressed correction construction simulation analysis for tension structures.     

金钱与爱情

[1] When the Romantic Movement was still in its first fervor, it was a I common matter of debate whether people should marry for love or for money. The young people concerned usually favored love, and their parents usually favored money. In the novels of the period the dilemma was felicitously solved by the discovery, on the last page, that the     

Optimization on bicriterion policies for M/G/1 system with second optional service

We compare the optimal operating cost of the two bicriterion policies, 〈p,T〉 and 〈p,N〉, for an M/G/1 queueing system with second optional service, in which the length of the vacation period is randomly controlled either by the number of arrivals during the idle period or by a timer. After all the customers are served in the queue exhaustively, the server immediately takes a vacation and may operate 〈p,T〉 policy or 〈p,N〉 policy. For the two bicriterion policies, the total average cost function per unit time is developed to search the optimal stationary operating policies at a minimum cost. Based upon the optimal cost the explicit forms for joint optimum threshold values of （p,T） and （p,N） are obtained.     

A study of optimal switching problem in limited-cycle with multiple periods

In a social system or production line,the restrictions of the cost and the due-time exist in each period.Generally,whether these restrictions are satisfied is dependent not only on the risks of this period,but also on the risks generated beforehand.We consider controlling the production process by switching the processing rate to a faster one at a given period.This paper deals with the optimal switching period to minimize the total expected cost of the production process.We first propose the optimal switching period model,and then the mathematic formulation of the total expectation is presented.Finally,the policy of optimal switching period is investigated in detail by numerical experiments.     

童年--一生中最幸福的时光?

It is about time somebody exploded1 that hoary2 old mythabout childhood being the happiest period of your life.Childhood may certainly be fairly happy,but its greatestmoments can’t compare with the sheer joy being anadult.Who ever asked a six-year-old for an opinion?Childrendon’t have opinions,or if they do,nobody notices.Adultschoose the clothes their children will wear,the books they willread and the friends they will play with.Mother and father arekindly but absolute dictators3.This have to be manipulated4 so     

Reconstruction of Current Density Distribution in Weld Area During Resistance Spot Welding of Aluminum Alloy Based on Magnetic Field

Magnetic flux density around the weld area was used to reconstruct the current density distribution during resistance spot welding(RSW) of aluminum alloy according to inverse problem theory. A current-magnetic field model was established and the conjugate gradient method was used to solve this model. The results showed that the current density was low at the center of nugget while high on the edge of nugget. Moreover, the welding time of 30ms—60 ms is a key period for nucleation. The current density distribution can reflect whether the weld nugget is formed or splashed, therefore it has the potential to monitor the weld quality of RSW.     

The Change of Meaning Of Some Engliish Words

No Language is fixed or unvarying. Ail languages show considerable linguistic variation at any given point of time or over a period of time. Words are the building materials of lan-     

The Contribution of International Student Mobility to Human Development and Global Understanding

International student mobility has been an important indicator for the degree of internationalisation in higher education. Today, international student mobility has moved from unorganised or self-organised study abroad to a variety of mobility forms organised within programmes. It has also become an issue of economic competitiveness, like attracting best talent, wealth creation and brain drain. This paper focuses on mobility as a limited period of study abroad （typically between six and 12 months） and not on mobility for the purpose of studying a whole degree programme abroad. Meanwhile, it takes ERASMUS program in Germany for example, analyzes the barriers to student mobility and possible solutions, and draws conclusions that widening participation and broadening geographical scope.     

The Analysis of Comparison Between English and Chinese Animal Idioms

Idioms are essence of a language and a kind of special and fixed phrases or short sentences in the long period of language use.Because animals have been considered as people’s best friends for hundreds of years,people adopt different species of animals as metaphors to express all their emotions.However,due to the different national characteristics between English and Chinese,such as geographical conditions and tradition so in most cases easterners and westerners have different attitudes and understanding towards same animals,of course,some animal idioms have the same meaning.     

外教教你学第六讲FOR EXAMPLE,SUCH AS的用法

1. The expression, "for example", can be used with greater freedom than the expression, "such as" . (for example使用的范围比such as要广。)You can say, "in the tropics-for example, in Kenya or Indonesia..." "For example" can come at the beginning of a sentence, or at the end, or in the middle. It can introduce instances of a general concept, (for example 可以出现在句首、句末或句     

Practicality in Curriculum Building: A Historical Perspective on the Mission of Chinese Education

This paper examines how the definition and interpretation of the concept gewu zhizhi 格物致知 (investigating things and extending knowledge), evolved along with Chinese intellectual efforts to construct the framework for Chinese learning which, in turn, had a profound impact on the development of educational curricula in different historical periods. In Confucian philosophy, “practicality” appears ambivalent, as it can refer to moral cultivation in daily life or knowledge in the material world. Such ambivalence, embodied in the evolution of the concept of gewu zhizhi, can be interpreted as a Chinese search for a well-rounded curriculum in education. Within this framework, this paper traces the origin of the concept in The Great Learning, and investigates how it was developed to refer specifically to natural studies and then to scientific knowledge introduced into China in the late Qing period. This historical reflection on Chinese education points to the shared humanistic values in the Confucian approach to education and in the Renaissance ideal of a liberal education. It calls for a search for a common humanity in rethinking the content and aim of a modern Chinese education.     

When and How to Teach Grammar

The paper reviewed Linguist and Professor Li Guanyi’s ESL experiences,and tried to find the critical period and appropriate approach for grammar teaching.It is concluded that it is more important to teach the use of language rather than the usage of it,especially for those beginners,and grammatical-translation approach is more effective in grammar teaching for the learners of higher cognitive abilities.     

话“天气”

Whatever happens or whatever the weather. ＂I＇ II be at the theatre tomorrow, come rain or shine-I wouldn＇t miss your debut performance for the world.＂To save money for a time that you might need it （during an emergency, for example）. ＂I try to save about 10% of my salary for a rainy day. You never know when you might need it.＂     

PRACTICAL ANALYSIS OF ORTHOTROPIC PLATES SUPPORTED IN ONE DIRECTION

A practical method for computing the one-way rectangular orthotropicplate(isotropic plate as a special case)is suggested in this paper.The supported condi-tions in two opposite edges may be simply supported,continuous or supportednonsymmetrically and the other two opposite edges are slide-supported or free.A series ofsimplified formulas are given for calculating the bending moments along the cross section(loaded section),in which the acting point of the concentrated load or the center of a rec-tangular uniform load is located.The valid range and accuracy of these formulas were stud-ied and the approximate results were examined and compared extensively with those by thetriangular series solution or finite element method.     

日本学生如何学习数学

A group of ninth-grade students are devising a formula for calculating the area of a stretch of winding road, and throughout the 50-minute period they remain intent on their task. They produce several possible solutions and reason them through until the principle behind the challenge is clear. At class's end, some students linger for more problem solving.     

Theoretical and experimental studies of heat transfer with moving phase-change interface in freezing and thawing of porous potting soil

Soil in a cold region is subject to frequent freezing and thawing cycles. Soil frozen for a prolonged period may cause adverse freeze damage to the plants due to cell dehydration or root cell rupture. It is important to understand the detailed heat transfer behaviors of the freezing and thawing processes to prevent freeze damage, and to devise proper mitigation measures for effective pot planting in cold regions. A theoretical model was developed to analyze the transient moving phase-change interface heat transfer in the freezing and thawing of porous potting soil. The theoretical derivation is based on the assumption that the soil freezes completely at a single temperature. Microscopic poromechanic effects on heat transfer behavior were ignored. The spatial domain of the problem was simplified to a 1 D spherical coordinate system with variation in the radial direction. Green＇s function was applied to solve for the time-dependent body temperature. Experiments were conducted for validation of the theoretical model Reasonable agreement between the theoretical predictions and experimental measurements was obtained. The theoretical model developed can be easily used to determine the sensitivity of various parameters in the freezing/thawing processes, e.g., thermal properties of soil, ambient temperature, and planting pot size.     

An Interesting Answer

Mary has been going to primary school for a week.At the end of the first week,ber father asked her,“Whieh period you like best at school？”     

The Enlightenment of Language Attrition and Forgetting to English Vocabulary Memory Strategies for College English Majors

This paper reviews the theory of language attrition,which refers to the loss or degradation of second language skills due to lack of using the second language for a certain period of time.Although our country attaches great importance to English language teaching,most of college English majors use English far less frequently than that of Chinese in real life,which makes them easily influenced by language attrition.Therefore,it is of great significance for college English majors to improve the efficiency of English vocabulary memory from the perspective of language attrition combined with Forgetting.This thesis consists of three parts.Chapter one is an analysis the concept of language attrition and Forgetting.Chapter two describes and analyzes the existing problems in current vocabulary memory among the college English majors via a questionnaire survey.The final chapter puts forward some corresponding countermeasures to help college English majors get rid of the influence of language attrition on vocabulary learning.     

《英语国家概况》模拟试题及分析(英文)

Ⅰ. Read the following unfinished statements or questions carefully. For each unfinished statement or question, four suggested answers marked A, B, C and D are given. Choose the one which you think best completes the statement or answers the question. Write the letter of the answer A, B, C, or D you have chosen in the corresponding space on the answer sheet. (40 points, 1 point for each)     

Retrofitting of RC Slabs Against Explosive Loads

With the increase of terrorist bomb attacks on buildings, there is a need to develop advanced retrofitting techniques to strengthen structures against blast loads. Currently, several guidelines including an Australian version for retrofitting reinforced concrete (RC) structures are available for the design of retrofitting systems against seismic and monotonic loads using steel or fibre reinforced polymer (FRP) plates that can be either adhesively bonded to the surface or near surface mounted to the concrete cover. However, none of these guidelines provide advice suitable for retrofitting structures subjected to blast loads. In this paper, numerical models are used to simulate the performance of retrofitted RC slabs subjected to blast loads. Airblast pressure distributions on the surface of the slabs estimated in a previous study are used as input in the analysis. A material damage model developed previously for concrete and an elastoplastic model for steel bars are employed in this research for modelling reinforced concrete behaviour due to explosive loads. The material models and blast loading are coded into a finite element computer program LS-DYNA3D to do the analysis. With the numerical model, parametric studies are conducted to investigate RC slabs retrofitted by either externally bonded or near-surface mounted plates or GFRP sheets subjected to blast loads. Discussion is made on the effectiveness of the retrofitting system for RC slabs against blast loads.