This article, from the angle of management, reviews the world history over the past century, studies the prospective progress in the new century, and discusses ways for promoting world peace and cooperation and realizing common development.
This article reviews studies and applications of mulching agriculture using thin plastic film in China. Plastic film mulching makes great effects on traditional mulching techniques of China. Over past 20 years with application of thin plastic film, some great changes have taken place in agricultural production of China, such as expanding suitable cultivated regions, regulating cropping distribution, increasing cropping index and promoting agricultural development in arid, semi-arid and salinized soil regions. Main mechanisms of yield increasing by plastic film mulching are： raising soil temperature, protecting soil water from evaporation, steadying soil environment, improving light and energy utilization efficiencies and promoting crop roots development. Problems and prospects of mulching agriculture using thin plastic film are reviewed at the end of the erticle.
Along with scale expanding and complexity enhancing of engineering object system, technology integration organizations which are of new style organizations come forth in engineering technology organization. This paper summarizes the historical significances of their emergence, discusses their architecture, roles and functions, working objects and contents, and describes the theoretical basis that they should know well and dominating methodologies and aids that they. Finally, the paper analyses the structure of their personnel and the normal relationship between them and the technological speciality organizations.
A 9-story brick-concrete building rapidly collapsed due to a landslide in Wulong County, China, on May 1st, 2001.The failure took place at the beginning of the rainy season. This paper discusses a number of scenarios to highlight the background geology, possible causes and mechanisms of the rapid movement, as well as the possible perched water conditions and the influence of man-made changes in the morphology. Of particular importance are preceding some related back analyses. For this, at first, a 2-D rigid-body limit equilibrium analysis is carried out in the present paper considering various related loads applied on the slope. Then, based on the geometric data investigated in the field and assuming the slide mass holding limit equilibrium, the shear strength parameters are back calculated out. The parameters are further used for back analyses of the landslide in order to explore the cause of landslide occurred through changing the cut-slope shape and groundwater table. The presented spreadsheet method is another contribution from this paper. Through the work, the authors conclude that apart from possible defects in the structure, it is certain that the landslide initiated the building collapse. Intense rainfalls must have increased water content, and hence fluidity of sandy clay intersected in the beds and layers of the sandstone. The process of excavation prior to building construction may have participated in the loss of stability.
This paper describes the historic evolution,present status and position of Chinese man-made fiber industry. It points out that the engineering and technical trend mainly are exploring differential and functional fibers,upgrading technology and equipment, producing high performance fibers,and developing green and new fibers. Also,the paper discusses bottle necks and improving measurement.
The progresses in explosive materials and engineering blasting in the recent five years at home and abroad are briefly described and the development prospects are pointed out.
This paper and paper ( Ⅱ ), aiming at the problems in the mainstream development of KDD, put forward a new academic thought that, in the knowledge discovery, the database can be restricted and deriven by the knowledge base whose structure can be in turn improved by the database. An open KDD system, KDD* , with double-base cooperating mechanism can thus be created. At the same time, the velocity, precision, and the auto-cognition of knowledge discovery can be imroved and the knowledge base is structurally equipped with the capacity of real time maintenance and to evolve by itself. This paper mainly deals with the corresponding relation between the database and knowledge base, which are the basis of double-base cooperating mechanism.
The complex systems and complexity is the kernel scientific problem of the 21st century. Due to the complexity and indetermination of complex systems, it is difficult to study the complex systems with the traditional reductive theory. The agent-based fuzzy computer simulation is approved in the paper, and a distributed simulation platform based on the agents is designed.
According to comprehensive analysis of river closure risk, a summary of two kinds of reasonable risk variables and models characteristic of high drop and high flow velocity in river closure project are presented. This paper also puts forward the specific methods and procedures to calculate river closure risk probability by means of the data surveyed in practice and stochastic simulation method with an illustrating case study made on the data surveyed in practice. The calculation results tentatively indicate the consistency of the two models and some rules of risk probability. Based on the case study and, evaluation and treatment of river closure risk are further analyzed. A suggestion of reasonable risk severity is given that lays a basic foundation for risk decision of river closure scheme.
The prompting acceleration of hoisting rope system determines the winderssitting comfort and the dynamic load in hoisting rope. The over dynamic load is the main factor which leads slipping or breaking out of hoisting rope. Based on the condition that the hoisting rope. Be regarded as the continuous flexible rod, and the equation of hoisting rope system, by the characteristic lines numerical value analyzing method and taking the ride comfort of hoisting cage and the little dynamic oscillation of hoisting rope as the aim, the rational acceleration curve of rope system is brought out in this paper, and it can provide reference for further study and design of mine winders.
The origin, the current status and existing problems of the same subject both at home and abroad in the research field of the service life of the aircraft were presented. Several key problems and their technical settlement were expounded emphatically, such as the model of corrosion fatigue of aircraft, the evaluation technique for corrosion damage of anticorrosion coats, the database of material-environment-service time and evolution law of corrosion-damage colony, the methods for theoretical analysis of the service life, the technique of nondestructive inspection (NDI) for corrosive damage and so on.
The study on traction behaviors of lubricants which have great influences on dynamic properties of rolling bearings is a vital field of elastohydrodynamic lubrication research. In this paper, a concise description of the traction test pattern, the results of test and data processing of No. 7007 and No. 7018 high speed aviation grease are involved. In the end, two useful formulas are advanced to calculate the traction coefficients of No. 7007 and No. 7018 lubricating grease.
As one of the most important cooperations between China and Brazil in high technology field, the engineering project of the China-Brazil joint TT&C supports to satellites is the first cooperation between the two countries in satellite TT&C supports. The engineering project was completed successfully, and it has provided China with plentiful experiences in international satellite TT&C cooperation, which are very useful for future cooperation. In this paper, the applications of operational research in the engineering project management are described.
In virtue of the use of the CSCW mode, the development and production of product can be implemented among distributed different areas and subjects. Meanwhile, this also increases the incidence of conflict. In this paper, through analyzing the present conflict management, its origin and the whole architecture and the topology of conflict management are described. Furthermore, the authors discusse the managed hierarchy and tri-layer service architecture of conflict. This offers the technological support to manage conflict problems in Web-based collaborative environment.
The development of oversea technique for construction of hydroelectric engineering is briefly described in this paper. Some important aspects on oversea hydroelectric technique, including the physical exploration, high dams and seismic resistance, optimum design on layout of hydropower houses, energy dissipaion in spillway tunnels, prestressed concrete lined tunnels, dam monitoring and repair of old dams, etc, are also described. Finally, some lessons from the comparison between Chinas and oversea hydroelectric techniques are suggested.
Modern structural materials are developing in the direction of compounding. The key to the development of composite materials is to create composite technology with low cost and high reliability. It can reduce the cost and improve the reliability of glass fiber composite by changing the traditional late composite to the new ecological early composite.