摘要 :
As the competition of Web Search market increases, there is a high demand for accurately judging the relations between the web pages and the user's requirement. In this paper, we propose an information retrieval method that tightl...
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As the competition of Web Search market increases, there is a high demand for accurately judging the relations between the web pages and the user's requirement. In this paper, we propose an information retrieval method that tightly integrates description logic reasoning and traditional information retrieval technique. The method expresses the user's search intention by description logic to infer the user's search object, and selects high-quality keywords according to the semantic context of the search object. Further, fuzzy describing logic is introduced to confirm the relations between the web pages and the user's search requirement, and the method to calculate the membership degree of web pages w.r.t the search requirement is presented. A prototype is implemented and evaluated, and the results show large improvements over existing methods.
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摘要 :
As the competition of Web Search market increases, there is a high demand for accurately judging the relations between the web pages and the user's requirement. In this paper, we propose an information retrieval method that tightl...
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As the competition of Web Search market increases, there is a high demand for accurately judging the relations between the web pages and the user's requirement. In this paper, we propose an information retrieval method that tightly integrates description logic reasoning and traditional information retrieval technique. The method expresses the user's search intention by description logic to infer the user's search object, and selects high-quality keywords according to the semantic context of the search object. Further, fuzzy describing logic is introduced to confirm the relations between the web pages and the user's search requirement, and the method to calculate the membership degree of web pages w.r.t the search requirement is presented. A prototype is implemented and evaluated, and the results show large improvements over existing methods.
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摘要 :
As the competition of Web Search market increases, there is a high demand for accurately judging the relations between the web pages and the user's requirement. In this paper, we propose an information retrieval method that tightl...
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As the competition of Web Search market increases, there is a high demand for accurately judging the relations between the web pages and the user's requirement. In this paper, we propose an information retrieval method that tightly integrates description logic reasoning and traditional information retrieval technique. The method expresses the user's search intention by description logic to infer the user's search object, and selects high-quality keywords according to the semantic context of the search object. Further, fuzzy describing logic is introduced to confirm the relations between the web pages and the user's search requirement, and the method to calculate the membership degree of web pages w.r.t the search requirement is presented. A prototype is implemented and evaluated, and the results show large improvements over existing methods.
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摘要 :
The thermal behavior of the energetic material 2,4,6,8,10,12- hexanitro-2,4,6,8,10,12- hexaaza- tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and its mixtures with aluminum under linear temperature control condition and adiabatic...
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The thermal behavior of the energetic material 2,4,6,8,10,12- hexanitro-2,4,6,8,10,12- hexaaza- tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and its mixtures with aluminum under linear temperature control condition and adiabatic condition were investigated by DSC-TG-MS-FTIR and ARC. Two different particle sizes of aluminum powder (10 μm and 50 nm) were added into CL-20. The influence of particle size on the thermal behavior of CL-20 was studied by using of these apparatuses. The enthalpies of reaction and onset temperatures were determined for various heating rates. The kinetic parameters were found according to Kissinger method, Ozawa method and Friedman method based on DSC data. The gaseous products from the decomposition of CL-20 and its mixtures were determined by simultaneous MS-FTIR experiments. ARC measurements were performed to investigate the thermal stability of the samples. The onset temperature, adiabatic temperature rise, self-heat rate, time to maximum rate and pressure-temperature profile were found from the data measured by ARC. Based on these results, the catalytic effect of aluminum powder was studied.
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摘要 :
The thermal behavior of the energetic material 2,4,6,8,10,12- hexanitro-2,4,6,8,10,12- hexaaza- tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and its mixtures with aluminum under linear temperature control condition and adiabatic...
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The thermal behavior of the energetic material 2,4,6,8,10,12- hexanitro-2,4,6,8,10,12- hexaaza- tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and its mixtures with aluminum under linear temperature control condition and adiabatic condition were investigated by DSC-TG-MS-FTIR and ARC. Two different particle sizes of aluminum powder (10 μm and 50 nm) were added into CL-20. The influence of particle size on the thermal behavior of CL-20 was studied by using of these apparatuses. The enthalpies of reaction and onset temperatures were determined for various heating rates. The kinetic parameters were found according to Kissinger method, Ozawa method and Friedman method based on DSC data. The gaseous products from the decomposition of CL-20 and its mixtures were determined by simultaneous MS-FTIR experiments. ARC measurements were performed to investigate the thermal stability of the samples. The onset temperature, adiabatic temperature rise, self-heat rate, time to maximum rate and pressure-temperature profile were found from the data measured by ARC. Based on these results, the catalytic effect of aluminum powder was studied.
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摘要 :
A novel material,Poly(4 ,4 -diazobenzene-2,5-thiophene) (PDABTh) was synthesized and its third-order opticalnonlinearity was studied using Z-scan technique with 20 ps laser pulse at 1064 nm. We measured the nonlinear refractiveind...
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A novel material,Poly(4 ,4 -diazobenzene-2,5-thiophene) (PDABTh) was synthesized and its third-order opticalnonlinearity was studied using Z-scan technique with 20 ps laser pulse at 1064 nm. We measured the nonlinear refractiveindex n_2=8.4x10~(-19)m~2/w with positive sign and nonlinear absorption coefficient β=1.8X 10~(-12)m/reverse saturableabsorption. The molecular second-order hyperpolarizabilityy was calculated to be 4.2x10~(30)esu. The special 7-electron structure may contribute to these relatively large non-linear optical properties. This suggests that the PDABTh may havea potential application in nonlinear optical devices.
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摘要 :
A novel material,Poly(4 ,4' -diazobenzene-2,5-thiophene) (PDABTh) was synthesized and its third-order optical nonlinearity was studied using Z-scan technique with 20 ps laser pulse at 1064 nm. We measured the nonlinear refractive ...
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A novel material,Poly(4 ,4' -diazobenzene-2,5-thiophene) (PDABTh) was synthesized and its third-order optical nonlinearity was studied using Z-scan technique with 20 ps laser pulse at 1064 nm. We measured the nonlinear refractive index n_2=8.4×10~(19) m~2/w with positive sign and nonlinear absorption coefficient β=1.8×10~(12) m/w with reverse saturable
absorption. The molecular second-order hyperpolarizabilityY was calculated to be 4.2×10~(30)esu. The special π-electron structure may contribute to these relatively large non-linear optical properties. This suggests that the PDABTh may have a potential application in nonlinear optical devices.
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摘要 :
In recent years, with the rapid increase in air traffic flow, flight conflict is becoming increasingly. It is very necessary on air safety risk quantitative analysis research. Especially in China, radar control is being gradually ...
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In recent years, with the rapid increase in air traffic flow, flight conflict is becoming increasingly. It is very necessary on air safety risk quantitative analysis research. Especially in China, radar control is being gradually implemented, in order to ensure air traffic safety, the study of quantitative analysis and evaluation of radar control on security risks has become gTeat significance and practical value. This paper studies the safety assessment method of aircraft radar separation in the case of air traffic flow increasing. Based on the close approach probability (CAP) model and the reference system comparison method, consider the various factors that affect flight safety, the radar separation evaluation model is established. Using statistical knowledge and measured data, the method of this study is verified by compare, the result is displayed in the premise of ensuring flight safety, radar type is related with radar safety separation. Reduced radar separation can greatly improve air traffic flow, ease flight delays, enhance control efficiency.
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摘要 :
In recent years, with the rapid increase in air traffic flow, flight conflict is becoming increasingly. It is very necessary on air safety risk quantitative analysis research. Especially in China, radar control is being gradually ...
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In recent years, with the rapid increase in air traffic flow, flight conflict is becoming increasingly. It is very necessary on air safety risk quantitative analysis research. Especially in China, radar control is being gradually implemented, in order to ensure air traffic safety, the study of quantitative analysis and evaluation of radar control on security risks has become gTeat significance and practical value. This paper studies the safety assessment method of aircraft radar separation in the case of air traffic flow increasing. Based on the close approach probability (CAP) model and the reference system comparison method, consider the various factors that affect flight safety, the radar separation evaluation model is established. Using statistical knowledge and measured data, the method of this study is verified by compare, the result is displayed in the premise of ensuring flight safety, radar type is related with radar safety separation. Reduced radar separation can greatly improve air traffic flow, ease flight delays, enhance control efficiency.
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With the onset of multiple wireless technologies, the end-host devices of today are multi-homed. This has led to research in the simultaneous use of multiple paths between the multi-homed end devices. New multipath transport proto...
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With the onset of multiple wireless technologies, the end-host devices of today are multi-homed. This has led to research in the simultaneous use of multiple paths between the multi-homed end devices. New multipath transport protocols such as Multipath TCP and Concurrent Multipath Transfer SCTP need to be fair to the existing transport protocols like TCP and SCTP in a congested network. One way of being fair is to couple the congestion control mechanisms of the protocol over its multiple utilized paths. This paper illustrates and compares the solutions that have been proposed to ascertain that Multipath TCP can yield an improved performance while being fair to standard TCP. In addition, this paper highlights improvements to one of the proposed solution - Dynamic Window Coupling. It is shown that the new solution performs best in most of the different scenarios of bottlenecks in a network with a higher preference given to being friendlier to TCP.
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