This essay summarizes the main technical points related to 100-meter-high concrete slab dam and analyzes the main problems and their causes of 200-meter-high concrete slab dam during construction period. Based on the main experiences of the super-high concrete slab dam built after the year of 2000, key technical issues related to 300-meter-high concrete slab dam that need research have been raised in this article.
In this paper, the principle of interaction between plastic volumetric and shear strains for rock and soil has been extended to the field of unsaturated soils. Two new interactions of suction-plastic volumetric strain and pore air pressure-plastic volumetric strain appear in the unsaturated state of a soil besides the interaction between plastic volumetric and shear strains. The suction possesses a dual property. Thereby the effect of the suction on plastic volumetric strain includes two opposite aspects. By means of this property of suction, the physical significance of effective stress parameter, effects of suction on volume change and preconsolidation pressure, and the mechanism of collapse upon wetting all can be explained. In addition, it is theoretically proved by application of this principle of interaction that the critical state line for unsaturated soils exists, and is unique and independent of the stress history.
With the rapid social and economic development in China, technology innovations in the extraction and utilization of mineral resources are demanded to address the problems associated with larger mining depth and other adverse conditions confronted by the mining industries, increase the efficiency of extracting mineral resources, and safeguard the safety and health of mining workers. To this end, the Chinese Ministry of Science and Technology (MOST) has launched a series of research directions through the 863 Program aimed at frontiers in the subject of personless mining to enhance technology innovations in personless mining and provide the mining industries with a fresh perspective to personless mining. In response to the MOST initiative, this paper presents a brief review on the development of automated mining technologies in the industrialized nations such as Canada, Australia, Finland and Sweden, outlines the major technological issues on the frontiers of automated mining, and proposes some avenues of advancing technology innovations in automated mining in China.
On the basis of considering each factor of urban public traffic line network, the decision-making method for the optimization of urban public traffic line network is set up by grey theory and fuzzy theory. This paper proposes to use interval numbers of three parameters to present grey fuzzy numbers. A comprehensive optimization method for urban public traffic line network is given by using theories above. It was applied to the practical optimization of urban public traffic line network in the city. Applied results indicate that the method improves the efficiency of urban public traffic line network.
The paper explains the great importance of the research on the innovative talents of the new times, and explores the connotation of the new times: taking innovation as the age spirit, including peaceful and developing age, civilized ecosystem age, knowledge economy age, democratic and law-ruled age, creative culture age, and reform and opening age explored from multi-views. In the paper the innovative talents of the new times are divided into four categories: the general, the top, the outstanding and the master. Five basic features of the innovative intellects of the new times are summarized as: the concepts with up-to-date sense of times, the comprehension of qualities, the advantage of orientations, the comprehension of researches and the innovation of accomplishments. The paper summarizes the training pattern of innovative talents of the new times and interprets the enlightenment of the research on innovative talents of the new times to the innovation of higher education.
In order to analyse the pressure sensitivity feature of high-dip fractures in the extra low-permeability sandstone reservoirs, the contrast experiment among matrix sample, bearing natural fracture sample and bearing artifieial fracture sample of extra low-permeability reservoirs in Ordos basin was accomplished. The experiment results indicate quite obvious pressure sensitivity feature of fractures in the extra low-permeability reservoirs. The matrix sample without fracture has medium pressure sensitivity and the samples with fractures have strong pressure sensitivity. The bigger the fracture aperture and permeability, the stronger the pressure sensitivity is. The stronger the pressure sensitivity, the lower the resumptive degree of fracture permeability is. The pressure sensitivity of fractures is of great significance to the development of the extra low-permeability sandstone reservoirs.
An experimental FM radio based non-cooperative bistatic radar is briefly described, and two related key techniques, i. e. line-of-sight (LOS) signal cancellation and targets detection, are listed in this paper. Other than algorithms appeared in most papers, NLMS based non-causal filters are used to equalize the array multi-channel differences. The LOS signal about 80 dB above the noise level is cancelled completely after joint time-space processing. Civil airplanes are detected 300 km away. Experimental data verifies the simplicity and effectiveness of the proposed method.
Heading face is a special underground workspace, generally forced ventilation is chose to supply fresh air, and the air movements in it belong to restricted wall-attached jet. According to the characteristics of workspace in heading face, this paper gives the definition of partial air age and average air age, and their models for calculating. Tracer gas method was used to menstruate the average air age, and numerical simulation has been used to calculate the ventilation airfield of restricted wall-attached jet and average air age of heading face, and elicit ventilation flow field and distributing of average air age of heading face. Based on them, relations between the air age and ventilation flow field, ventilation validity are analyzed, and the mathematical model of air exchange efficiency and ventilation efficiency of heading face were set up. The study revealed that the major influences to air age are air-flow organization and blast volume, and to air quality are air age and pollutant concentration. The conclusion of this research provides a kind of new theory basis for appraising the ventilation validity of heading face.
An on-line tracking self-learning algorithm for fuzzy basis function (FBF) neural network classifier is proposed in this paper. Based on the previous possibility distribution of the clusters, which is kept within the sample mean and covariance matrix with forgetting factor, a strategy for constructing the target output of the new training sample set is given. With the new sample set the FBF network can be trained to track the variable clustering boundary. Meanwhile, a recursive algorithm for computing the sample mean and covariance matrix with forgetting factor is also proposed to overcome the difficult of storing the vast old training samples. The proposed method is used for fault recognition of the rotating machinery, and the results show that it is feasible and effective.
A basic requirement for passive state estimation using single observer is the existence of a unique tracking solution. This leads to the question of observability. The target state is observable over the time interval if, and only if, it is uniquely determined by the measurements taken in that interval. In this paper, the state-observability problem for passive target tracking by angle measurements is analyzed using three methods: the geometrical method, the elementary algebraic method and linear system method. The observability for target tracking with frequency measurements is also analyzed. Degree of observability is discussed. And a concise review of papers on observability analysis is presented.
MR damper is analyzed on its mechanical characteristic, and is applied in multi-dimension damping in this paper. A kind of three-translation parallel mechanism is used as main mechanism of multi-dim damping, whose position and dynamics formula are deduced. The input signal of controller is from the result of equation of kinematics, and LQR is used as the semi-active control arithmetic. Considering complexity of the dynamics equation in dynamic process, a way is used in control progress when the mechanism is in a steady state through which the entire flat roof is limited adjacent to an equilibrium position. The result of emulation confirms that the controller is effective.
Trajectory tracking is one of the core problem in navigation with mobile robots. In this article, feedback linearization method is used in the design of trajectory tracking controller for nonholonomic vehicle. Robustness of the tracking algorithm is studied via simulation. Engineering problems, such as design of parameter observer, are introduced at last.
K-means algorithm is one of common clustering algorithms, but the cluster center initialization is a hard problem. In this paper, a hierarchical-based initialization approach is proposed for K-Means algorithm. The general clustering problem is treated as weighted clustering problem, the original data is sampled level by level to reduce the data amount. Then clustering is carried out at each level by top-down. The initial center of each level is mapped from the clustering center of upper level and this procedure is repeated until the original data level is reached. As a result, the initial center for the original data is obtained. Both the experimental results on simulated data and real data show that the proposed method has high converging speed, high quality of clustering and is insensitive to noise, which is superior to some existing clustering algorithms.
Based on steady state incompressible Reynolds-averaged Navier-Stokes equation, turbulence model, the three-dimension airflow and concentration fields in passenger car are calculated numerically. Regarding passengers as cubes and the exhalant CO2 as representative contaminant respectively, the airflow and concentration distributions are investigated in non-empty state. The results show that existing sew supply modes make the airflow distribution homogeneous except for the ends. Body heat and solar radiation have much influence on airflow and temperature fields. The air distribution in occupied passenger car differs from that in empty one. The heat flux from body heat and solar radiation produces a much big temperature gradient in occupied passenger car. The concentration is low in gangway zone while high in seat zone with crowded passengers. The concentration in middle section is higher than that in end section and contaminant gathers in respiratory region, and the polluted air can´t be exchanged effectively in seat zone, which is disadvantageous to air quality in passenger car.
Simulating biological immune mechanism to implement performance rejuvenation is a new research approach for computing grid. This paper analyzes and compares the immune process's characteristics and computing system's rejuvenation, sets up the logical model of system rejuvenation based on immune agent above simulates the biological immune mechanisms to monitor resource usage and diagnose performance degradation, constructs the mathematics model, then puts forward a method to make decision for rejuvenation policy. On the basis of above an application regarding audio-video resource transaction process system as background is studied, a two-stage hyper-exponential model is proposed to evaluate system performance. The results of case study indicate that this method is effective and feasible.
The paper makes experiment about six T-shaped cross section column frame joints under low periodic cycle loads. The paper uses variable parameters of beam section height, the axis-pressed ratio and the volume ratio of hoop reinforcement to research cracks formation and development and the failure mechanism of the joints. The paper points out that joints'crack shape appears as reverse "K" but not the common rectangular joints' "X" shape, and the endure mechanism is inclined to the steep press-pole mechanism. At the same time, this paper makes use of a software ANSYS to develop the language APDL two times to T-shaped column joints to carry on nonlinear finite element analysis, adopts discrete cracking model smeared cracking model, and carries on the contrast analysis with experiment result. Analysis enunciates that nonlinear finite element analysis calculation results fit in aill with experiment result. The paper changes procedure parameters to cause the core area shear-press breakage, and to do further argument about the formation of the joints crack and the joints failure mechanism.
Starting with the analysis of the definition and concept of the theory of architecture, the framework of architectural theory and the filling theory innovation, the author gives his understanding on the framework of architectural theory with Chinese characteristics.
Germanium is a typical dispersed element, it is the most important semiconductor material except for silicon. Today, Germanium is used principally in the field of infrared optical, telecommunication fiber optics, a polymerization catalyst for polyethylene terephthalate(PET), a kind of commercially important plastic in solar cell and in biomedicine, and as a semiconductor and substrate in electronics circuitry. Germanium resource is scarce in the earth. The reserve of germanium in China ranks first in the world. Yunnan Province owns about40percent of germanium reserve of China and owns the basis of research and development in the field of infrared optical, so it is very significant to develop germanium industry in Yunnan. This paper analyzes the exterior and interior circumstances for the industrial development of germanium in Yunnan, brings forward the orientation of development and the total target of Yunnan germanium industry from2006to2020, and discusses the industrial chains of germanium, product position, industrial layout, the supporting system and the key projects.
Distillate from atmospheric distillation of bio-oil accounts for about50%by weight. Bio-oil can't be applied for requiring complete evaporation before combustion, but can be employed for atomizing combustion. The composition of bio-oil is complicated, phenols derived from lignin can be extracted by vacuum distillation or/and steam distillation. And the distillation method can also be used to improve the ov erall fuel properties of bio-oil such as stability, heat value, the pH value and so on.
Engineering is a construction activity and process to reform the nature under certain restriction (including decision. ,design, construction and evaluation), following necessary procedure, design documents, regulations, rules and standards to integrate basic production elements and resource with specific related engineering science, engineering technology and management principles, its final result is an engineering body with predetermined functions. The essence of engineering is the sum of mass activities to utilize and reform the nature. The basic characters of engineering are integration, mass involved, dynamic and with agreement. The close relationship between engineering and science and technology expresses the incorporation of engineering and science and technology, as well as confluence, unity and interaction of engineering with science and technology.
Through the research of the water-salt movement under different ground condition for the water saving irrigation in dry area, it has been found that there is the symptom of redistribution of water and salt in certain area:when the evolvement of water and salt movement occurs in vertical and horizontal direction, there is also the important symptom of sideward movement and has certain domino effect. This paper analyses the technology for treatment of the salt soil at home and abroad, and discusses the new mode of salt drainage under both the condition of water-salt directional movement and the condition of salt movement to the earth's surface. The study has the practical meaning for research and discussion on the new method of salt soil amending in dry agricultural area in China.
In this paper, developing process and current state of Chinese IC industry are analyzed firstly. Then development trend of world IC industry is introduced, and seven pieces of advice on how to accelerate Chinese IC industry are presented:to construct incompact and lengthwise direction IC enterprise organization mode;to invest more in important domain in IC industry and constitute preferential policy;to optimize IC industrial structure and improve its capability;to encourage the collaboration between complete appliance firms and IC design firms;to accelerate the development of IC industry colony;to build state research center and improve the capability of research and application; to cultivate the talented person and build better situation in IC industry.
Aiming at improving the strength of glass fibre, the paper proposes a nascent state preimpregnation composite modification technique, which enable glass fibre to keep the extremely high neomorphosis strength.
This paper proposes the model for loan portfolio under probability criterion, and designs the hybrid optimization algorithm based on random simulation to solve the model. The algorithm can solve the models with the return rates with any probability distributions, and is not subject to the assumption that the return rates have normal distributions. The feasibility of the algorithm is verified by two examples.
According to the complex geologic condition of deep excavat ion in Huainan, probability-integral method is ewployed to study the for surface displacement due to coal extraction by optimization mining layouts. Correlation parameters about subsidence under thick loose overburden and duplication mining are obtained. The results obtained may provide guidance for the subsidence-administrating. It is valuable of this paper to other coal mines which have similar geological and mining conditions.
To deal with program fault, the method is usually to report them with return-value or emergency. But, when the program fault emerges in the state-orient model, how to make the program return to the state the fault point belong to or take further corresponding actions, the return-value or emergency can't do. In order to realize processing the fault automatically, this article presents automatic program design with uniting combined coding and state redundant design, and proposes its frame model and algorithm. The model is used for decreasing faults of state-switch("prevent" ) and increasing capability of fault-restore("cure" ). At last, part of the results presented in this paper are applied to a vending machine project and the tests show that the results are satisfactory.
To investigate the problem of tracking multiple short range high speed maneuvering targets with multi- static radar system, a tracking algorithm based on parallel processing mechanism is derived. The whole measurement association course was divided into some parallel sub-courses, moreover, an established target's tracking course is separated into two parallel3-D sub-courses which execute iterative filtering processes with synthetic distance-sum and Doppler velocity. Simulation results show that the algorithm can accurately track multiple maneuvering targets in clutter with fast speed. Meanwhile, it has good convergence and stability.
Limited by computing resource, network resource and today's technologies, the scalability of collaborative virtual environment(CVE)has not been efficiently solved until now. The paper discusses the communication model of large-scale CVE first and then devises a CVE architecture based on open grid services architecture(OGSA). Utilizing grid service the CVE architecture separates CVE function realizations from physical resource to solve the scalability of CVE. In addition, the paper focuses on the research of virtual world management service and some related services such as interest management service, consistency management service and concurrent management service which are key issues to solve the scalability of CVE. At last, a CVE case based on Globus Toolkit is developed to validate the feasibility of the proposed CVE architecture and methods.
Aimed at improving wear, corrosion resistance and enhancing fire retardance, several plasma surface treating methods on titanium alloys had been presented, which included add-arc glow hydrogen-free carburizing plasma depositing on titanium alloy, double glow plasma hydrogen-free carburizing on titanium alloy, double glow Mo diffusing, double glow Cr diffusing, double glow Cu diffusing. The results showed that gradient layer had formed on the titanium alloys surface, that was of great significance on wear, corrosion resistance and fire burning resistance.
Human beings are in process of stepping into the technological society. In this society, engineer, as the main body of technological invention and technological application, will directly influence the human being's survival and development by their ethical tropism and ethical responsibility consciousness. It has become necessary to restrict and control the action of engineer from the lay of ethic. The paper discusses five basic ethical principles which engineer should follow in modern technological society.
The necessity and actual application of an on-line temperature monitoring system used for10kV high voltage electric cable of industrial enterprises has been studied in this paper. Selecting method for temperature sensors, composition of temperature monitoring system and its operating have been illustrated as well. The information processing software and trouble shooting expert system software, basic information network of power facility, and on-site bus line technology used in power system are introduced. The online trouble shooting and diagnosis for high voltage electric cable and cable joints with non stop of power supply have been achieved.
Enterprise innovation is the basic requirement for building an innovative country. Since the launch of the Three Gorges Project in1993, the project has been faced with a lot of world-class difficulties. Based on reality, the Three Gorges builders realized great breakthroughs in the dam fast-concreting technology, the hydro design, installation and manufacturing of the700kW turbine, the stability of the high-side-slope of the double-way five stage ship lock, the water system on extra high water head, the manufacturing and installation of the grand scale door and some other key technologies through the means of technology integration and innovation, introducing new technologies into China, fully absorbing them and innovating or innovating in some original technologies. As a result, the Three Gorges Project has accomplished great achievements. According to the" Diamond System" model by Michael E. Porter in analyzing the national competitive strength, the Three Gorges Project has its own characteristics in production factors, requirement conditions, and the performances of related and supporting industries, and also in the strategy and structure of the enterprise, competitors of the enterprise and some other aspects. To rely on the support of the government and the society and seize the precious opportunity for hydropower development, the builders take the Three Gorge Project construction as a big stage for technology innovation and winning honor for the country. Nevertheless, talking about most enterprises in China at present, some protruding problems like low rate of technology introduction and absorption, the lack of intellectual property right and the lack of research input still exist, which severely hamper innovation. To realize the goal of building an innovative country in2020, domestic enterprises should foster and improve the innovation ability in six aspects, namely, relying on the resources of the country and the society, bringing their innovative ability into full play, carrying out the scientific development concept, tapping their self-independent innovation ability, strengthening the construction of the innovation team, and increasing in research input and exerting a coordinated effect and collective scale advantage of innovation.
It is necessary to analyze each factor that affects the stability of mine ventilation system in order to comprehensively and quantitatively analysis the stability of mine ventilation system. Piston wind velocity engendered by hoisting system is one of the primary factors. Using Bernoulli equation and continuity equation of non-steady flow, the paper presents the calculation formula of piston wind velocity in mine hoisting systems by assuming different passing section. According to the formula, piston wind velocity can be quantitatively calculate, which will be used as basic data for the stability analysis of mine ventilation system. In this way, the stability of mine ventilation system can be further analyzed, which will benefit the safety of productien.
Ionic liquids, as green solvents, can preferably solve environmental pollution which is caused by using volatile organic solvents. They have become a hot research field in separation of metal ions by solvent extraction. It is introduced in this paper of the definition of ionic liquid, developing history, character, etc. The characteristics, synthetic methods and development direction of ionic liquids being used for extracting metal ions are emphatically summarized.
Combining membrane bioreactor and A2/O crafts, MB(A2/O) craft is developed to promote the technology with high efficiency for phosphorus and nitrogen removal. This report studies the performances of aerobic and anaerobic phosphorus uptake and the characters of microorganism of municipal sewage treated by MB(A2/O) craft, and analyzes its mechanism as well. The results indicate that the phosphate accumulating organisms take up 20%~40% of active sludge. There are a great deal of DPB which make use of NOx-N as electron acceptor to have denitrifying phosphorus removal and take up approximately 35. 66%~67. 83% of PAOs. The average rate of aerobic phosphorus uptake is 2. 30mgP·gMLSS-1·h-1, and the highest rate is 5. 44mgP·gMLSS-1·h-1. The average velocity of anaerobic phosphorus uptake is 1. 56 mgP·gMLSS-1·h-1, and the biggest rate is 1. 94 mgP·gMLSS-1·h-1.
This article attempts to analyze the characteristics and hazards of the respirable dust, and introduces the new technologies for respirable dust prevention and control at home and aboard in recent years. Based on analyzing and comparing with different technologies of reducing dust, the results show that charged fog with wetting agent is a high- efficiency technology for the removal of the respirable dust of steel enterprise. Through the theoretical analysis and experimental study, it obtains ideal effect when this dedusting technology is applied to the removal of the respirable dust in a steel enterprise.
A novel method for quick measuring moisture of garnierite by means of microwave sensor was investigated, and the effects of the different moisture content on the measuring results were analyzed and discussed in detail. Finally, experimental equipment, properties and application notes are presented, and the moisture measuring by microwave sensor during pyrometallurigical processing of garnierite for nickel products is also described.
After1980s, China's private education has displayed strong development tendency. Private Universities have undertaken certain responsibility and obligation in the process of the higher education entering into popular stage. But meanwhile there are also some pressing issues in its internal management and school behavior. In the process of their development, private universities need to refine and standardize the internal management, as well as improve management from the height of strategy.
By microscope detection of microbe in wastewater from printing and dyeing of one company in Baoding, some rules of microbe diversification are found in cut-and-try process. This article simply introduces some kinds of microbe in different phase, and simply analyses the cause of microbes diversification. This article will offer some referenced to wastewater´s cut-and-try process.