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Application of Prediction Techniques in Carbonate Karst Reservoir in Tarim Basin 被引量:5
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作者 陈广坡 撒利明 +2 位作者 韩剑发 管文胜 Guan Wensheng 《Applied Geophysics》 SCIE CSCD 2005年第2期111-118,F0003,共9页
Carbonate karst reservoir is the emphases of Tarim's carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir ... Carbonate karst reservoir is the emphases of Tarim's carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper. 展开更多
关键词 Tarim basin karst reservoir seismic response reservoir prediction and comprehensive evaluation
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写在前面的话
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《标准计量与质量(广西)》 2003年第5期4-4,共1页
关键词 《米制公约》 单位 科学 技量技术
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Quantum Secure Communication Using a Class of Three-Particle W State 被引量:2
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作者 DONG Li XIU Xiao-Ming GAO Ya-Jun CHI Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期359-362,共4页
A theoretical scheme of quantum secure communication using a class of three-particle W states is proposed. In the scheme,two communicators may communicate after they test the security of the quantum channel.The receiv... A theoretical scheme of quantum secure communication using a class of three-particle W states is proposed. In the scheme,two communicators may communicate after they test the security of the quantum channel.The receiver can obtain the secret message determinately if the quantum channel is safe.The present scheme can be realized without using teleportation. 展开更多
关键词 quantum cryptography quantum secret communication W state
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Constrained multi-degree reduction of rational Bézier curves using reparameterization 被引量:1
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作者 CAI Hong-jie WANG Guo-jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第10期1650-1656,共7页
Applying homogeneous coordinates, we extend a newly appeared algorithm of best constrained multi-degree reduction for polynomial Bezier curves to the algorithms of constrained multi-degree reduction for rational Bezie... Applying homogeneous coordinates, we extend a newly appeared algorithm of best constrained multi-degree reduction for polynomial Bezier curves to the algorithms of constrained multi-degree reduction for rational Bezier curves. The idea is introducing two criteria, variance criterion and ratio criterion, for reparameterization of rational Bezier curves, which are used to make uniform the weights of the rational Bezier curves as accordant as possible, and then do multi-degree reduction for each component in homogeneous coordinates. Compared with the two traditional algorithms of "cancelling the best linear common divisor" and "shifted Chebyshev polynomial", the two new algorithms presented here using reparameterization have advantages of simplicity and fast computing, being able to preserve high degrees continuity at the end points of the curves, do multi-degree reduction at one time, and have good approximating effect. 展开更多
关键词 Rational Bezier curves Constrained multi-degree reduction Reparameterization
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Roller Profile Online Measurement Based on Ultrasonic Circulation Pulse-echo Technology 被引量:1
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作者 WEN Shu-hui XU Feng-rong 《Semiconductor Photonics and Technology》 CAS 2007年第3期238-242,共5页
In order to meet the high precision requirement of wide steel strip in industry field, a novel online measurement of roller profile based on sonic circulation and pulse-echo technology was introduced. All kinds of the... In order to meet the high precision requirement of wide steel strip in industry field, a novel online measurement of roller profile based on sonic circulation and pulse-echo technology was introduced. All kinds of the factors influencing the accuracy of roller profile online measurement were analyzed in detail and error compensation analysis of system was accordingly presented. In order to reduce count error, field program gate array(FPGA) was introduced and a highprecision data acquisition system was designed based on digital phase-shift technology. Experiments indicate that the standard deviation of measure data was 7.27 μm, which showed the feasibility and validity of the proposed method, and realized the roll profile measurement with high precision. 展开更多
关键词 ultrasonic circulation roll profile online measurement pulse-echo technology error compensation
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Exploring the Sample Quality Using Rough Sets Theory for the Supervised Classification of Remotely Sensed Imagery 被引量:1
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作者 GE Yong BAI Hexiang +1 位作者 LI Sanping LI Deyu 《Geo-Spatial Information Science》 2008年第2期95-102,共8页
In the supervised classification process of remotely sensed imagery, the quantity of samples is one of the important factors affecting the accuracy of the image classification as well as the keys used to evaluate the ... In the supervised classification process of remotely sensed imagery, the quantity of samples is one of the important factors affecting the accuracy of the image classification as well as the keys used to evaluate the image classification. In general, the samples are acquired on the basis of prior knowledge, experience and higher resolution images. With the same size of samples and the same sampling model, several sets of training sample data can be obtained. In such sets, which set reflects perfect spectral characteristics and ensure the accuracy of the classification can be known only after the accuracy of the classification has been assessed. So, before classification, it would be a meaningful research to measure and assess the quality of samples for guiding and optimizing the consequent classification process. Then, based on the rough set, a new measuring index for the sample quality is proposed. The experiment data is the Landsat TM imagery of the Chinese Yellow River Delta on August 8th, 1999. The experiment compares the Bhattacharrya distance matrices and purity index zl and △x based on rough set theory of 5 sample data and also analyzes its effect on sample quality. 展开更多
关键词 supervised classification measuring the sample quality rough set
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Secondary cooling technology for high-efficiency continuous billet-casting
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作者 陈登福 《Journal of Chongqing University》 CAS 2007年第4期242-248,共7页
The mathematical model of high-efficiency continuous billet casting was developed, incorporating the effective spraying water coefficient and the effective specific spraying water flowrate of secondary cooling. To rea... The mathematical model of high-efficiency continuous billet casting was developed, incorporating the effective spraying water coefficient and the effective specific spraying water flowrate of secondary cooling. To realize uniform cooling in secondary cooling zones, the spraying cooling structure and the arrangement of nozzles were redesigned and optimized, and an additional spraying cooling zone was used. A new secondary cooling model of spraying water was built. It was found that the required spraying water flowrate of a cooling zone was related with the casting speed, the casting temperature, the compositions of liquid steel and the cooling water temperature of secondary cooling. The operation of the reformed caster proved that the spraying cooling structure and the new secondary cooling model were suitable, and the casting speed was greatly enhanced. The highest casting speed was (3.8 to 4.0) m/min for billet with a section of 150× 150 mm^2. The quality And the outout of the billet were imoroved, andthe economical benefit was heightened. 展开更多
关键词 high-efficiency continuous casting water flowrate of secondary cooling secondary cooling model of sprayingwater billet quality
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Outlier Detection in Near Infra-Red Spectra with Self-Organizing Map 被引量:2
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作者 李晓霞 李刚 +4 位作者 林凌 刘玉良 王焱 李健 杜江 《Transactions of Tianjin University》 EI CAS 2005年第2期129-132,共4页
A new method to detect multiple outliers in multivariate data is proposed. It is a combination of minimum subsets, resampling and self-organizing map (SOM) algorithm introduced by Kohonen,which provides a robust way w... A new method to detect multiple outliers in multivariate data is proposed. It is a combination of minimum subsets, resampling and self-organizing map (SOM) algorithm introduced by Kohonen,which provides a robust way with neural network. In this method, the number and organization of the neurons are selected by the characteristics of the spectra, e.g., the spectra data are often changed linearly with the concentration of the components and are often measured repeatedly, etc. So the spatial distribution of the neurons can be arranged by this characteristic. With this method, all the outliers in the spectra can be detected, which cannot be solved by the traditional method, and the speed of computation is higher than that of the traditional neural network method. The results of the simulation and the experiment show that this method is simple, effective, intuitionistic and all the outliers in the spectra can be detected in a short time. It is useful when associated with the regression model in the near infra-red research. 展开更多
关键词 OUTLIER near infra-red spectra minimum subsets RESAMPLING self-organizing map
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Ultrasonic Resonator Techniques for Broad-band Spectroscopy and for High-resolution Sound Velocity Measurement of Liquids
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作者 Udo Kaatze Frieder Eggers 《Journal of Measurement Science and Instrumentation》 CAS 2010年第1期1-9,共9页
This review gives a short introduction into the principles of ultrasonic measurement techniques for liquids, using cavity resonators. Guidelines for the resonator design in broad-band ultrasonic stxctroscopy as well a... This review gives a short introduction into the principles of ultrasonic measurement techniques for liquids, using cavity resonators. Guidelines for the resonator design in broad-band ultrasonic stxctroscopy as well as in high-resolution single-frequncy or narrowband applications are presented. Deviations of the field configuration in real cells frtxn that in an ideal resonator are discussed and relations for the mode spectrum of cavity fields are given. Recent resonator measurement procedures and methods of data evaluation are mentioned briefly. Some examples of measurements show the extended usability of ultrasonic resonator techniques in basic science and in a wide range of applications for rrkaterials characterization, in manufacturing processes, as well as in control routines. 展开更多
关键词 ultrasonic measurements liquids sound velocity attenuation coefficient resonator techniques ultrasonic spectrometry
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Relative navigation for satellite formation flight using a continuous-discrete converted measurement Kalman filter
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作者 雪丹 曹喜滨 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期450-454,共5页
The present paper develops an approach of relative orbit determination for satellite formation flight.Inter-satellite measurements by the onboard devices of the satellite were chosen to perform this relative navigatio... The present paper develops an approach of relative orbit determination for satellite formation flight.Inter-satellite measurements by the onboard devices of the satellite were chosen to perform this relative navigation,and the equations of relative motion expressed in the Earth Centered Inertial frame were used to eliminate the assumption of the circular reference orbit.The relative orbit estimation was achieved through a continuous-discrete converted measurement Kalman filter design,in which the measurements were transformed to the inertial frame to avoid the linearization error of the observation equation.In addition,the situation of the coarse measurement period(only microwave radar measurements are available)existing was analyzed.The numerical simulation results verify the validity of the navigation approach,and it has been proved that this approach can be applied to the formation with an elliptical reference orbit. 展开更多
关键词 satellite formation flight relative navigation continuous-discrete converted measurement Kalman filter
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Applying sub-band energy extraction to noise cancellation of ultrasonic NDT signal
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作者 Qi ZHANG Pei-wen QUE Wei LIANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第8期1134-1140,共7页
In ultrasonic non-destructive tests, the echo signal at the flaw is highly complex due to the interference of multiple echoes with random amplitudes and phases, and is disturbed by all kinds of noises, such as thermal... In ultrasonic non-destructive tests, the echo signal at the flaw is highly complex due to the interference of multiple echoes with random amplitudes and phases, and is disturbed by all kinds of noises, such as thermal noise, digitalization noise, and structure noise. In this paper, the ultrasonic signal was decomposed by empirical mode decomposition (EMD) to obtain the in-trinsic mode function (IMF) components according to ultrasonic defect echo signals occuring at the corresponding time, and the energy of the ultrasonic signal was concentrated. The IMF component selection criterion based on sub-band energy extraction was proposed to extract the ultrasonic signal component accurately and automatically from IMF components. When the selected IMF components were filtered by a band pass filter, the signal-to-noise ratio (SNR) was enhanced greatly. 展开更多
关键词 Empirical mode decomposition (EMD) Signal-to-noise ratio (SNR) DE-NOISING Non-destructive testing (NDT) Intrinsic mode function (IMF)
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ANALYSIS AND MEASUREMENT OF LARGE DYNAMIC RANGE RF SWITCH INTER-MODULATION
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作者 Han Zhouan 《Journal of Electronics(China)》 2008年第3期422-427,共6页
Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic sw... Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic switch circuit and its inter-modulation, and studies in detail the measurement methods and systems of RF switch intercept point. It has provided cascaded simulation testing methods, which can accurately measure the PF switch, of which the second or third order intercept point value is above 75dB and 60dB, respectively. As the testing results are consistent with the theoretical analyses, it proves that the validity of the method satisfies the requirements of large scaled linearity measurement in engineering. 展开更多
关键词 Large dynamic range Radio Frequency (RF) switch Intercept point MEASUREMENT
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Quantum Secure Communication by Using GHZ State in High-Dimensional Hilbert Space
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作者 GAO Gan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期368-370,共3页
We propose a quantum superdense coding secure communication scheme by using GHZ state.This scheme combines the ideas of quantum superdense coding and sequence transmission.Its distinct advantage is high source capacit... We propose a quantum superdense coding secure communication scheme by using GHZ state.This scheme combines the ideas of quantum superdense coding and sequence transmission.Its distinct advantage is high source capacity.In addition,in checking eavesdropping,we need not to destroy quantum entanglement. 展开更多
关键词 GHZ state measurement quantum secure communication re-arranging orders
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Research on P2P Traffic Monitoring System based on DPI Technology
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作者 Zhiqiang Ma 《International Journal of Technology Management》 2014年第9期85-87,共3页
This paper focuses on the key technologies of P2P technology and network traffic monitoring, which focuses on AC automaton and bypass interference control technology, and on based of it, we design a new P2P traffic mo... This paper focuses on the key technologies of P2P technology and network traffic monitoring, which focuses on AC automaton and bypass interference control technology, and on based of it, we design a new P2P traffic monitoring system. The system uses DPI and DFI recognition technology, as well as straight loss and bypass interference control technology, basically meet the recognition and control of P2P traffic. Finally, the test results show that this system recognition accuracy of P2P traffic is high, good control effect, function and performance meet the design requirements. 展开更多
关键词 monitoring system network traffic traffic monitoring P2P traffic monitoring
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Vector Shift Method for Islanding Detection Based on Simulation Test
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作者 侯梅毅 高厚磊 +1 位作者 刘炳旭 邹贵彬 《Transactions of Tianjin University》 EI CAS 2008年第2期123-127,共5页
Vector shift(VS)is one of the typical methods used for islanding detection in distributed generations.This paper investigates the impact of both the active power imbalance and load variation on VS method.The investiga... Vector shift(VS)is one of the typical methods used for islanding detection in distributed generations.This paper investigates the impact of both the active power imbalance and load variation on VS method.The investigation was conducted via simulation test in the power system dynamic simulation laboratory of Shandong University.The results show that it will take longer time for the VS relay to detect islanding state with the decrease of active power imbalance.In some cases,the vector shift angle is smaller than the setting and VS method would not be able to detect islanding state.In addition,the performance of VS method is impacted by the load variation in normal operation in which the distributed generator is operated in parallel with the main grid.The simulation results show that VS method would cause nuisance tripping if the load changes sharply. It can be summarized that VS method would be unable to reliably discriminate islanding state and normal system disturbances in some cases. 展开更多
关键词 distributed generation islanding detection vector shift physical model simulation islanding operation
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Technological Content of the Import of Services and the Transformation of Growth Patterns of China's Industrial Economy
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作者 戴翔 金碚 《China Economist》 2014年第2期58-74,共17页
Based on the latest approach for measuring technology content of import of services and with the contribution of total factor productivity(TFP) to gross industrial output as the indicator for measuring the growth patt... Based on the latest approach for measuring technology content of import of services and with the contribution of total factor productivity(TFP) to gross industrial output as the indicator for measuring the growth pattern of China's industrial economy,this paper provides an empirical study on the effect of import technology content of trade in services on the development pattern of China's industrial economy between 2004 and2011.Result of econometric test reveals that the technology content of import of services has a significant positive effect on transforming the growth pattern of China's industrial economy.Moreover,import of new types of trade in services with high technology such as computer and information services has a much stronger positive effect compared with import of traditional trade in services with relatively low technology content such as transport.In terms of different industrial sectors,technology content of import of services has the greatest effect on transforming the development pattern of China's technologyintensive industrial sectors,followed by capital-intensive,resource-intensive and laborintensive sectors respectively.Transformation of the development pattern of China's industrial economy cannot be isolated from the system of global division of work.Against the backdrop of global service sector fragmentation,China should take the important opportunities in the development of global trade in services and give more attention to improving the quality of import of services in the interest of transforming the development pattern of its industrial economy. 展开更多
关键词 trade in services technology content of import development pattern ofindustrial economy
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Dynamic Integrity Measurement Model Based on vTPM 被引量:2
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作者 Ruizhong Du Wangyang Pan Junfeng Tian 《China Communications》 SCIE CSCD 2018年第2期88-99,共12页
With the development of cloud computing, virtualization technology has been widely used in our life. Meanwhile, it became one of the key targets for some attackers. The integrity measurement in virtual machine has bec... With the development of cloud computing, virtualization technology has been widely used in our life. Meanwhile, it became one of the key targets for some attackers. The integrity measurement in virtual machine has become an urgent problem. Some of the existing virtualization platform integrity measurement mechanism introduces the trusted computing technology, according to a trusted chain that the Trusted Platform Module(TPM) established for trusted root to measure the integrity of process in static. But this single chain static measurement cannot ensure the dynamic credible in platform running. To solve the problem that the virtual trusted platform can not guarantee the dynamic credibility, this paper put forward Dynamic Integrity Measurement Model(DIMM) based on virtual Trusted Platform Module(v TPM) which had been implemented with typical virtual machine monitor Xen as an example. DIMM combined with virtual machine introspection and event capture technology to ensure the security of the entire user domain. Based on the framework, this paper put forward Self-modify dynamic measurement strategy which can effectively reduce the measurement frequency and improve the measurement performance. Finally, it is proved that the validity and feasibility of the proposed model with comparison experiments. 展开更多
关键词 XEN trusted chain integrity mea-surement Self-modify measurement strategy dynamic integrity
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A Limited Dependent Variable Analysis of Integrated Pest Management Adoption in Uganda 被引量:2
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作者 Jackline Bonabana-Wabbt Daniel Blaine Taylor 《Journal of Agricultural Science and Technology(A)》 2012年第10期1162-1174,共13页
Integrated Pest Management (IPM) technologies can reduce pest damage to crops by emphasizing non-chemical control methods thereby reducing potential negative effects of chemicals on the environment while preserving ... Integrated Pest Management (IPM) technologies can reduce pest damage to crops by emphasizing non-chemical control methods thereby reducing potential negative effects of chemicals on the environment while preserving profitability. This study investigates the adoption of eight IPM practices including intercropping, crop rotation, two improved varieties, incorporating a "striga chaser" in sorghum production, changing planting dates, altering planting density and fertilizer use. Explanatory variables include economic factors, social factors, management factors, and institutional factors. Results were consistent across logit and ordered logit analyses. Most factors affecting adoption across all crops and technologies are economic factors, including labor availability, technology resource requirements, technology complexity, and the level of expected benefits. Social factors are generally less associated with IPM technology adoption than either market or institutional factors. Results indicate that the evaluated technologies were scale-neutral and that farmer age and education level did not affect technology adoption. 展开更多
关键词 IPM LOGIT cumulative logit ADOPTION Uganda.
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Damage detection of frames using the increment of lateral displacement change
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作者 王建民 陈龙珠 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第3期202-212,共11页
The method proposed in this paper is based on the fact that the damage in different types of structural members has distinctive influence on the structural stiffness. The intrinsic mechanical property of the structure... The method proposed in this paper is based on the fact that the damage in different types of structural members has distinctive influence on the structural stiffness. The intrinsic mechanical property of the structure is tapped and fully utilized for damage detection. The simplified model of the flexibility of frames treats the individual storeys as springs in series and the frame as an equivalent column. It fully considers the main deformation of all beams and columns in the frame. The deformation property of the simplified model accorded well with that of the actual frame model. The obtained increment of lateral displacement change (IOLDC) at the storey level was found to be very sensitive to the local damage in the frame. A damage detection method is pro- posed using the IOLDCs as the damage identification parameters. Numerical examples demonstrate the potential applicability of this method. 展开更多
关键词 Damage detection Increment of lateral displacement change Static test FRAME Equivalent column
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A Research on MPLS-Based Transition Technology of Next-Generation Internet
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作者 Changan Ma 《International English Education Research》 2014年第10期51-53,共3页
With the continuous advancement of Intemet technology, Intemet is penetrating to various sectors of the society and every comer of life, which spawned a variety of needs. Therefore. the development of the Interact sho... With the continuous advancement of Intemet technology, Intemet is penetrating to various sectors of the society and every comer of life, which spawned a variety of needs. Therefore. the development of the Interact should ahvays meet the needs of customers. How the next generation of the lntemet will develop? How the technology will get the breakthrough? How to use MPLS technology to make the transition of the lntemet more practical and more scientific? And so on. These questions need network technical staff give full play of the technical expertise to promote Interact technology' continues moving forward. This paper first introduces MPLS technology, and then analyzes the overall architecture of the next generation Interact and the service quality required by the next generation lntemet, and at last study how to make the MPLS-based transition technology of next-generation more perfect. 展开更多
关键词 Next Generation Network: Quality of Service MPLS Technology Integration Services Multi-Label Prolocol Switching
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