This paper introduces the development history of the project design of spaceflight launching site in China and the main forms used in the design, and points out that there shouldn't exist only one fixed mode for the spacecraft launch. China should, according to its national condition, design and build the launching project facility and device that correspond to the technology development of spacecraft and carrier rocket.
In the early stage of the universe, during the hadronic era, the light velocity was larger than c, in fact was v=75c. This implies that light velocity has been decreasing in time slowly, from v down to the present value c. On the other hand, based on the measurements of 128 quasar absorption lines, the average increase in fine-structure constantαwas6×10-6 over the past 6~12Ga. Scientists think it was aroused by the light-speed variation. It would be interesting to investigate if these facts have influenced the past history of the universe. This paper also discusses some problems of faster-than-light research profoundly, such as the velocity definition of the microscopic particles, the velocity of gravitation, the interaction speed of the quantum-entangle-state(QES), and the over distance action.
This paper discusses the unforeseeability and foreseeability of innovation, and on this basis, classifies innovations into three types: foreseeable, unforeseeable and that situated between above two. The paper analyses some problems and phenomena relative to innovation in China and presents views and suggestions for promotion of innovation.
The developing course of the Western architecture from the Modernism to the Post-Modernism, and that of various schools of Avant唱garde are reviewed. The paper advocates to develop a road of China's own "New Modernism" in the process of modernization, based on the national conditions, with emphasis on returning to the basic spirit of Modernism, the Rationalism, and drawing on the experience of the Post唱 Modernism in paying close attention to the tradition, and opposing the individuation of the Avant-garde.
With the aim of providing low DC sources in gasoline inverter generator set, the switching power supply with simple structure has been designed. Less ripple voltage, smaller in volume, lower cost are its features. On the basis of design principle of high frequency transformer, an accessory power supply (15W active power) with 4 sets of outputs is designed. The experimental results show its validity.
On the basis of providing the definition of public security system, this paper puts forward the concept of public security comprehensive index, discusses the characteristics of uncertainty and the method of system non-optimum analysis, at the same time, it establishes the running system of public security. Based on the security index, it provides the index of public security control ability and discusses the analysis method of uncertain factor. Studies have shown that the scientific and technological contribution rate of public security is the key to the scientific and technological strategic research. This paper also sets up the function between science and technology input and public security target, discusses the relationship between input and output of science and technology contribution increase ratio, and finally establishes basic thinking of public security science and technology research system and research planning.
In traditional Chinese medicine, tongue moisture plays an important role in tongue diagnosis. However, there are still some problems in conventional measurement. Therefore, a hygroscope, which uses digital humidity and temperature sensor, was developed to test tongue moisture based on mass transfer means. This paper presents its testing principle and the design method of its hardware and software. This hygroscope finds itself with some attractive features, such as portability, handy operation, low power consumption, etc. It has been proved that the standard deviation of this tester, only 2.9%, is better than that of other conventional instruments, and the tongue moisture could be measured rapidly and accurately.
The elastic instability of a gel cylinder was researched with classical elastic theory. The non-classic boundary condition of the elastic instability has been educed by the energy functional variation analysis. So a criterion equation of the elastic instability can be got. Through the analysis of the equation, it is found that the elastic instability is relevant to the radius, intrinsic scale and instable wavelength of the cylinder.
This paper tries to describe the continuous transformation characteristic of reservoir operations with optimal control theory. After constructing the optimal control model of reservoir o perations, the paper presents the necessary condition of optimal control of reservoir operations using maximum principle and analyzes the characteristic and concrete expression of optimal control strategy of reservoir operations in different conditions and environment. At last, an analysis of a numerical example is presented and the results indicate the approach is valid.
The catalytic oxidizer assembly(COA)is an important part of the trace contaminant control subassembly in manned spacecraft. Temperature control in COA via a new self-tuning fuzzy logical controller (FLC)is analyzed in this paper. The new tuning method applies the bang-bang on-line tuned method to the design of the self-tuning FLC for obtaining the system parameters. On the basis of these parameters, the input and output scaling factors are calculated with simple tunable formulas. Then the proposed self-tuning FLC is realized by combining the scaling factors and the normal look-up table. It can realize self-tuning parameters, and simplify the design. Simulation results show that the proposed self-tuning FLC is fit for controlling the temperature of COA and isn't sensitive to parameter changes.
In this paper, a computational evacuation discrete time model(EDTM) has been presented to analyze the building egress evacuation time problem with previous works, and discusses the advantages of the use of the modified model over the use of the previous model. EDTM uses crowd flow theory and discrete computational methods to identify various width of egress that are available to the occupants for movement, which is more accurate and practicable because the crowd flow rate is variable, while the crowd flow rate as the function of crowd density based on the empirical relations between density and velocity of crowd movement. A case of stadium stand egress is chosen for the validity of EDTM, and a comparison of EDTM with previous model and computer simulation indicates that both the EDTM and the simulation curves are found to give better predictions than the previous model. Based upon the results, EDTM shows great value in dealing with stadium, especially the2008Beijing Olympic stadium, evacuation time calculation, egress performance design, selecting and optimizing of routes and so on.
The hyperbolic mild slope equation has been widely used as an effective mathematic model to simulate the propagation of water waves in coastal zones. In this paper, the grid system that collocated in time and staged in space has been used to discretize the hyperbolic mild slope equation and two examples have been used to validate the numerical model. The numerical results show that the numerical model used in the paper can be effectively used in the numerical simulation of the hyperbolic mild slope equation.
In this paper, on the basis of the constitutive relation theory which includes inner variables, with the general explicit description of incremental strain thermal-plastic constitutive relations and the specific incremental thermal-plastic constitutive relations, combining the simulation of X ray load and the tube responsing problem which is greatly important in practice, the self-contained equation group about the stress wave in the flexible material_steel composite shell problem is developed. Numerical simulations are carried out with the presented constitutive relations for explosive-filled sphere fracture problem and the results are analyzed. The thickness of explosive and flexible material that influences the load of the interface is discussed emphatically.
An approach to inspection of incipient faults in dam by non_d estructive testing is a so far emerging inspection technology in the world. In this paper, inspection principles, system integrity and key items of the new blasting source-based technology for inspection of incipient faults in dam, different from common non- destructive testing, are presented, following briefing experiences in dam inspection by elastic wave CT in recent years. Specific procedures and goals for further spreading and application as well as conclusion are introduced finally.
Technologic problems of top coal recovery ratio, rock burst, coal spontaneous combustion and gas accumulation induced by hard top-coal or roof's fall in coal mining were introduced. Current research and development trend of hydraulic fracture weakening for hard top-coal or roof was analyzed, including the law of crack expanding induced by hydraulic fracture in rock mass, mescoscopic structure alteration of cracked rock mass by seepage pressure and its macroscopic mechanics response, controlling technology of hydraulic crack's expanding, the technology of enveloping drillbore and weakening effect monitoring.
Researching flow in aspirating lines in altiplano environment can offer gist of designing air aspirating lines of HSASD (High Sensitivity Aspirating Smoke Detector)at tableland. Velocity equation of air aspirating line and velocity equation of aspirating aperture could be derived from continuity equation and dynamics equation. Average velocity of air aspirating line and average velocit y of aspirating aperture could be concluded when air aspirating line had only single aspirating aperture. Contrasting average velocity of air aspirating line and aspirating aperture at high altitude and normal atmosphere pressure concluded difference of them and main factors that affected flow of air aspirating lines at high altitude. Flow velocity of air aspirating lines and aspirating aperture is mainly affected by viscosity coefficient, negative pressure at aspirating pump inlet. Equal flow velocity of air aspirating lines and aspirating aperture can be got through shortening aspirating lines length. Equation 4.14 gives a compute method of shortening aspirating lines length in altiplano environment.
Based on the crystal silicon solar cells' power complete differential equation, and combined with the experimental facts that the open circuit voltage and power vary along with the cells'temperature and insolation, the independence of the parameters that determine solar cells' operating state is investigated. After a strict mathematic deducing process, it is concluded that the insolation, cells' temperature and load resistance are the independent parameters of crystal silicon solar cells, and that the series resistance is a function of cells' temperature. The series resistance's experimental results show the theoretical analysis's accuracy.
Based on the actual construction design project and the human distribution in some large supermarkets, two improved design projects are presented because the evacuation staircase width of the fire zones are not distributed symmetrically. One is the improvement to current fire zone design, making the distribution of evacuation staircase width more symmetrically by setting shared evacuation staircase. The other is to relocate the related fire zone, decrease the area of current fire zones and add one more fire zone. The occupant evacuation times of three evacuation scenarios are simulated by EVACNET4. Results show that when the fire zone area is large, to symmetrically distribute the evacuation staircase width of the fire zones is more effective for evacuation. Setting shared evacuation staircase will help for evacuation and improve the efficiency of using the staircase. Decreasing the fire zone area will shorten the evacuation distance, and the evacuation time will be reduced.