This paper investigates the effect of launching multiple weapons against an area target of normally distributed elements. We provide an analytical form of the average damage fraction and then apply it to obtain optima...This paper investigates the effect of launching multiple weapons against an area target of normally distributed elements. We provide an analytical form of the average damage fraction and then apply it to obtain optimal aimpoints. To facilitate the computational efforts in practice, we also consider optimizations over given constrained patterns of aimpoints. Finally, we derive scaling laws for optimal aimpoints and optimal damage fraction with respect to the radius of the area target.展开更多
The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational geometry.The advances in EOS technology and the ex-pansion of wide-area remote s...The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational geometry.The advances in EOS technology and the ex-pansion of wide-area remote sensing applications have increased the practical significance of SMEATO.In this paper,an adaptive local grid nesting-based genetic algorithm(ALGN-GA)is proposed for developing SMEATO solutions.First,a local grid nesting(LGN)strategy is designed to discretize the target area into parts,so as to avoid the explosive growth of calculations.A genetic algorithm(GA)framework is then used to share reserve information for the population during iterative evolution,which can generate high-quality solutions with low computational costs.On this basis,an adaptive technique is introduced to determine whether a local region requires nesting and whether the grid scale is sufficient.The effectiveness of the proposed model is assessed experimentally with nine randomly generated tests at different scales.The results show that the ALGN-GA offers advantages over several conventional algorithms in 88.9%of instances,especially in large-scale instances.These fully demonstrate the high efficiency and stability of the ALGN-GA.展开更多
The geothermal resources in Fujian Province are mainly hydrothermal resources of medium-low temperature.To better understand the whole process and conditions of heat control in the middle and deep crust,this study foc...The geothermal resources in Fujian Province are mainly hydrothermal resources of medium-low temperature.To better understand the whole process and conditions of heat control in the middle and deep crust,this study focuses on the analysis of heat accumulation model in Hongtang Area of Xiamen,and the main conditions of the model such as faults and sags are explored and interpreted in detail by using gravity and wide-field electromagnetic methods.4 main faults(F33,F2,F12 and HT-F1)and 10 secondary faults(HT-F2,HT-F3,HT-F4,HT-F5,HT-F6,HT-F7,HT-F8,HT-F9,HT-F10 and HT-F11)were inferred,and the distribution range of sags was delineated.The convective geothermal system is composed of four components:Heat source,geothermal reservoir,heat-conductive fault and heat retaining cover,which form a quaternary heat accumulation model.According to the model,the intersection of the main faults F12,HTF1 and F33 can be delineated as the primary target area of geothermal exploration,while the intersection of the secondary faults(F12 and HT-F6;F12 and HT-F2;HT-F9,HT-F10 and F12;F12 and HT-F11;F33 and HT-F3;HT-F8 and HT-F3;HT-F2,HT-F10 and HT-F1)can be delineated as the secondary target area.Borehole DR01,which is located in the primary target area,shows that the water temperature increases from fast to slow in the depth range of 0–500 m,and stays at 36℃below 500 m.The reliability of the heat accumulation model and the target area was tested via geothermal boreholes,which is of great significance to the exploitation and utilization of geothermal resources in Hongtang Area of Xiamen.展开更多
This paper proposes a hybrid method, called CNOP–4 DVar, for the identification of sensitive areas in targeted observations, which takes the advantages of both the conditional nonlinear optimal perturbation(CNOP) and...This paper proposes a hybrid method, called CNOP–4 DVar, for the identification of sensitive areas in targeted observations, which takes the advantages of both the conditional nonlinear optimal perturbation(CNOP) and four-dimensional variational assimilation(4 DVar) methods. The proposed CNOP–4 DVar method is capable of capturing the most sensitive initial perturbation(IP), which causes the greatest perturbation growth at the time of verification;it can also identify sensitive areas by evaluating their assimilation effects for eliminating the most sensitive IP. To alleviate the dependence of the CNOP–4 DVar method on the adjoint model, which is inherited from the adjoint-based approach, we utilized two adjointfree methods, NLS-CNOP and NLS-4 DVar, to solve the CNOP and 4 DVar sub-problems, respectively. A comprehensive performance evaluation for the proposed CNOP–4 DVar method and its comparison with the CNOP and CNOP–ensemble transform Kalman filter(ETKF) methods based on 10 000 observing system simulation experiments on the shallow-water equation model are also provided. The experimental results show that the proposed CNOP–4 DVar method performs better than the CNOP–ETKF method and substantially better than the CNOP method.展开更多
This paper proposed a robust method based on the definition of Mahalanobis distance to track ground moving target. The feature and the geometry of airborne ground moving target tracking systems are studied at first. B...This paper proposed a robust method based on the definition of Mahalanobis distance to track ground moving target. The feature and the geometry of airborne ground moving target tracking systems are studied at first. Based on this feature, the assignment relation of time-nearby target is calculated via Mahalanobis distance, and then the corresponding transformation formula is deduced. The simulation results show the correctness and effectiveness of the proposed method.展开更多
In laser-guided bomb attacking process,the target indication from the laser target designator is the premise for the bomb to hit the target accurately.Considering the lack of quantitative study of the irradiation area...In laser-guided bomb attacking process,the target indication from the laser target designator is the premise for the bomb to hit the target accurately.Considering the lack of quantitative study of the irradiation area of the laser target designator,this paper,based on the existing aircraft motion model and the laser transmission model,uses two aircraft as respectively the carrier of the laser-guided bomb and the carrier of the laser designator and proposes a method to calculate the global irradiation area of the airborne laser designator.By using the proposed algorithm,the global irradiation area when attacking a large flat target or a large spherical target is simulated respectively.Finally,according to the simulation results,the influences of different factors on the shapes of the irradiation area are discussed in detail.展开更多
Objective: to explore the role of medical archiving and communication system in the training of target delineation ability of oncology graduate students and regular training students. Methods: this subject will take t...Objective: to explore the role of medical archiving and communication system in the training of target delineation ability of oncology graduate students and regular training students. Methods: this subject will take the newly admitted graduate students and planning students as the research objects, and senior doctors will use the medical archive and communication system to carry out training on sectional anatomy and target area delineation in the form of department lectures. The application of medical archiving and communication system in improving the ability of target area delineation was explored by self before and after comparison, and the ability of target area delineation was tested before training, after training and three months after graduation. To evaluate the theoretical knowledge and practical operation level of target area delineation in order to explore the superiority and feasibility of medical archiving and communication system in improving the target area delineation ability of oncology graduate students and planning students. Results: there was a statistical difference between the accuracy of target area delineation after relevant knowledge training and three months after graduation by using the medical archive and communication system and before training (P < 0.05). Conclusion: using the medical archive and communication system to train oncology graduate students and training students in relevant knowledge can significantly improve their ability to outline the target area, better adapt to the development of oncology, and lay a solid foundation for becoming a qualified oncologist in the future.展开更多
Land use regionalization is a strategic measure for the rational use,management and protection of land resources based on local conditions.Based on the needs of targeted poverty alleviation and rural revitalization st...Land use regionalization is a strategic measure for the rational use,management and protection of land resources based on local conditions.Based on the needs of targeted poverty alleviation and rural revitalization strategy and the analysis on the natural and socioeconomic conditions,characteristics of land resources,and the current status of land use in Luquan County,corresponding regionalization indices were selected from four aspects:economic environment conditions,socioeconomic conditions,land resources and land use structure,and poverty alleviation and development level,a scientific and feasible index system for land use regionalization was constructed,and land use in Luquan County was regionalized by using systematic cluster analysis method.The results show that the 16 townships(towns)of Luquan County were divided into four land use regions,poverty alleviation region for development of new town and characteristic industries in the southwest(I),agricultural development and ecological poverty alleviation region in central mountainous area(II),poverty alleviation region for development of characteristic agriculture and tourism towns in eastern plateau mountainous area(III),and poverty alleviation region for development of characteristic industries and protection of land economy in the northern alpine valley area(IV).In addition,suggestions were put forward for the rational use of land in each region.展开更多
When the space robot captures a floating target, contact impact occurs inevitably and frequently between the manipulator hand and the target, which seriously impacts the position and attitude of the robot and grasping...When the space robot captures a floating target, contact impact occurs inevitably and frequently between the manipulator hand and the target, which seriously impacts the position and attitude of the robot and grasping security. ＂Dynamic grasping area＂ is introduced to describe the collision process of manipulator grasping target, and grasping area control equation is established. By analyzing the impact of grasping control parameters, base and target mass on the grasping process and combining the life experience, it is found that if the product of speed control parameter and dB adjustment parameter is close to but smaller than the minimum grasping speed, collision impact in the grasping process could be reduced greatly, and then an ideal grasping strategy is proposed. Simulation results indicate that during the same period, the strategy grasping is superior to the accelerating grasping, in that the amplitude of impact force is reduced to 20%, and the attitude control torque is reduced to 15%, and the impact on the robot is eliminated significantly. The results would have important academic value and engineering significance.展开更多
This study examines the time and regime dependencies of sensitive areas identified by the conditional nonlinear optiflml perturbation （CNOP） method for forecasts of two typhoons. Typhoon Meari （2004） was weakly no...This study examines the time and regime dependencies of sensitive areas identified by the conditional nonlinear optiflml perturbation （CNOP） method for forecasts of two typhoons. Typhoon Meari （2004） was weakly nonlinear and is herein referred to as the linear case, while Typhoon Matsa （2005） was strongly nonlinear and is herein referred to as the nonlinear case. In the linear case, the sensitive areas identified for special forecast times when the initial time was fixed resembled those identified for other forecast times. Targeted observations deployed to improve a special time forecast would thus also benefit forecasts at other times. In the nonlinear case, the similarities among the sensitive areas identified for different forecast times were more limited. The deployment of targeted observations in the nonlinear case would therefore need to be adapted to achieve large improvements for different targeted forecasts. For both cases, the closer the forecast time, the higher the similarities of the sensitive areas. When the forecast time was fixed, the sensitive areas in the linear case diverged continuously from the verification area as the forecast period lengthened, while those in the nonlinear case were always located around the initial cyclones. The deployment of targeted observations to improve a special forecast depends strongly on the time of deployment. An examination of the efficiency gained by reducing initial errors within the identified sensitive areas confirmed these results. In general, the greatest improvement in a special time forecast was obtained by identifying the sensitive areas for the corresponding forecast time period.展开更多
Repeater optimization is the key for SOC （System on Chip） interconnect delay design. This paper proposes a novel optimal model for minimizing power and area overhead of repeaters while meeting the target performance...Repeater optimization is the key for SOC （System on Chip） interconnect delay design. This paper proposes a novel optimal model for minimizing power and area overhead of repeaters while meeting the target performance of on-chip interconnect lines. It also presents Lagrangian function to find the number of repeaters and their sizes required for minimizing area and power overhead with target delay constraint. Based on the 65 nanometre CMOS technology, the computed results of the intermediate and global lines show that the proposed model can significantly reduce area and power of interconnected lines, and the better performance will be achieved with the longer line. The results compared with the reference paper demonstrate the validity of this model. It can be integrated into repeater design methodology and CAD （computer aided design） tool for interconnect planning in nanometre SOC.展开更多
Against a background of continuing loss of biodiversity, it is argued that for the successful conservation of threatened plant species we need to ensure the more effective integration of the various conservation actio...Against a background of continuing loss of biodiversity, it is argued that for the successful conservation of threatened plant species we need to ensure the more effective integration of the various conservation actions employed, clarify the wording of the CBD targets and provide clearer operational guidance as to how they are to be implemented and their implementation monitored. The role and effectiveness of protected areas in conserving biodiversity and in particular plant species in situ are discussed as are recent proposals for a massive increase of their extent. The need for much greater effort and investment in the conservation or protection of threatened species outside protected areas where most plant diversity occurs is highlighted. The difficulties involved in implementing effective in situ conservation of plant diversity both at an area-and species/population-based level are discussed. The widespread neglect of species recovery for plants is noted and the desirability of making a clearer distinction between species recovery and reintroduction is emphasized. Key messages from a global overview of species recovery are outlined and recommendations made, including the desirability of each country preparing a national species recovery strategy. The projected impacts of global change on protected areas and on species conservation and recovery, and ways of addressing them are discussed.展开更多
Aircraft single-hit vulnerability/survivability is usually expressed as the probability of kill or the vulnerable area in case of being given a random threat （e.g. a fragment） hit on the aircraft. In this paper, int...Aircraft single-hit vulnerability/survivability is usually expressed as the probability of kill or the vulnerable area in case of being given a random threat （e.g. a fragment） hit on the aircraft. In this paper, introducing the ＂equivalent target method＂ in lethality field into the aircraft vulnerability assessment, a generic vulnerability calculation model is proposed. In order for a good representation of reality, the model considers the threat change of state-of-motion during the threat penetrating into the components successively. Application shows that the proposed generic model has solved the Pk/h （probability of kill given by a hit on the component） calculation problem in aircraft vulnerability assessment, and is easier to be computerized than other commonly used models.展开更多
The electromagnetic scattering principles of geological radar targets and various influential factors were discussed, and the importance of researching into the electromagnetic scattering features of the targets to th...The electromagnetic scattering principles of geological radar targets and various influential factors were discussed, and the importance of researching into the electromagnetic scattering features of the targets to the actual prospecting task was pointed out.展开更多
Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, a...Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, as an research case, this article analyzes and summarizes the industry-supporting poverty alleviation achievements and successful experience of two typical relocation areas (Shanhou Village and Eyang Village) in Xundian County. Practice has shown that the key to industry-supporting poverty alleviation lies in targetedness to strengthen the participation of poor farmers in industrial development. The interests of poverty alleviation entities should be linked by market mechanism to establish a benign interaction between all parties for win-win situation, thereby effectively guaranteeing the long-term and healthy development of poverty alleviation by supporting industry.展开更多
Taking the Dapingzhang copper-polymetallic deposit in Yunnan Province, China as the research object, the maximum entropy model was used to extract the mining information, and the mineral resource prediction model was ...Taking the Dapingzhang copper-polymetallic deposit in Yunnan Province, China as the research object, the maximum entropy model was used to extract the mining information, and the mineral resource prediction model was established by using the exploration data of the deposit and related regions in this area, so as to determine the prospecting prospect area in the study area. In this paper, the Jacknife analysis module of maximum entropy model is used to quantitatively rank the importance of 39 geochemical element variables, and finally obtain the prospecting prospect map of the study area. The research results show that the Dapingzhang mining area has the potential to find hidden ore in the deep and surrounding areas, and the northern and southern ends and western sides of the rock ore control structural belt in the eastern region of the mining area have good prospecting prospects. The research results provide an important basis for the deployment of follow-up exploration work in the study area, and the maximum entropy model has a good application effect in mineral resources exploration.展开更多
In order to find out the various restrictions and difficulties of financial poverty alleviation in rural areas,taking Hubei Province as an example,this paper firstly introduced current situations of financial poverty ...In order to find out the various restrictions and difficulties of financial poverty alleviation in rural areas,taking Hubei Province as an example,this paper firstly introduced current situations of financial poverty alleviation in rural areas of Hubei Province. Then,it analyzed problems confronted by financial poverty alleviation in rural areas of Hubei Province:( i) subjects of financial poverty alleviation not mature and poverty alleviation risks increased,( ii) backward agricultural insurance system,( iii) rural credit system not perfect,and( iv) weak guiding policies of financial poverty alleviation. Finally,it came up with pertinent recommendations: improving rural financial environment,actively developing the innovation mode of financial poverty alleviation,and strengthening relevant supervision efforts.展开更多
文摘This paper investigates the effect of launching multiple weapons against an area target of normally distributed elements. We provide an analytical form of the average damage fraction and then apply it to obtain optimal aimpoints. To facilitate the computational efforts in practice, we also consider optimizations over given constrained patterns of aimpoints. Finally, we derive scaling laws for optimal aimpoints and optimal damage fraction with respect to the radius of the area target.
基金supported in part by the National Natural Science Foundation of China(NSFC),under Grant Nos.72271074 and 72071064.
文摘The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational geometry.The advances in EOS technology and the ex-pansion of wide-area remote sensing applications have increased the practical significance of SMEATO.In this paper,an adaptive local grid nesting-based genetic algorithm(ALGN-GA)is proposed for developing SMEATO solutions.First,a local grid nesting(LGN)strategy is designed to discretize the target area into parts,so as to avoid the explosive growth of calculations.A genetic algorithm(GA)framework is then used to share reserve information for the population during iterative evolution,which can generate high-quality solutions with low computational costs.On this basis,an adaptive technique is introduced to determine whether a local region requires nesting and whether the grid scale is sufficient.The effectiveness of the proposed model is assessed experimentally with nine randomly generated tests at different scales.The results show that the ALGN-GA offers advantages over several conventional algorithms in 88.9%of instances,especially in large-scale instances.These fully demonstrate the high efficiency and stability of the ALGN-GA.
基金supported by the National Natural Science Foundation of China (Grants Nos. 41902242)the Geological Survey Projects Foundation of the Institute of Hydrogeology and Environmental Geology (Grants Nos. DD20190303, DD20221773)。
文摘The geothermal resources in Fujian Province are mainly hydrothermal resources of medium-low temperature.To better understand the whole process and conditions of heat control in the middle and deep crust,this study focuses on the analysis of heat accumulation model in Hongtang Area of Xiamen,and the main conditions of the model such as faults and sags are explored and interpreted in detail by using gravity and wide-field electromagnetic methods.4 main faults(F33,F2,F12 and HT-F1)and 10 secondary faults(HT-F2,HT-F3,HT-F4,HT-F5,HT-F6,HT-F7,HT-F8,HT-F9,HT-F10 and HT-F11)were inferred,and the distribution range of sags was delineated.The convective geothermal system is composed of four components:Heat source,geothermal reservoir,heat-conductive fault and heat retaining cover,which form a quaternary heat accumulation model.According to the model,the intersection of the main faults F12,HTF1 and F33 can be delineated as the primary target area of geothermal exploration,while the intersection of the secondary faults(F12 and HT-F6;F12 and HT-F2;HT-F9,HT-F10 and F12;F12 and HT-F11;F33 and HT-F3;HT-F8 and HT-F3;HT-F2,HT-F10 and HT-F1)can be delineated as the secondary target area.Borehole DR01,which is located in the primary target area,shows that the water temperature increases from fast to slow in the depth range of 0–500 m,and stays at 36℃below 500 m.The reliability of the heat accumulation model and the target area was tested via geothermal boreholes,which is of great significance to the exploitation and utilization of geothermal resources in Hongtang Area of Xiamen.
基金partially supported by the National Key R&D Program of China (Grant No. 2016YFA0600203)the National Natural Science Foundation of China (Grant No. 41575100)
文摘This paper proposes a hybrid method, called CNOP–4 DVar, for the identification of sensitive areas in targeted observations, which takes the advantages of both the conditional nonlinear optimal perturbation(CNOP) and four-dimensional variational assimilation(4 DVar) methods. The proposed CNOP–4 DVar method is capable of capturing the most sensitive initial perturbation(IP), which causes the greatest perturbation growth at the time of verification;it can also identify sensitive areas by evaluating their assimilation effects for eliminating the most sensitive IP. To alleviate the dependence of the CNOP–4 DVar method on the adjoint model, which is inherited from the adjoint-based approach, we utilized two adjointfree methods, NLS-CNOP and NLS-4 DVar, to solve the CNOP and 4 DVar sub-problems, respectively. A comprehensive performance evaluation for the proposed CNOP–4 DVar method and its comparison with the CNOP and CNOP–ensemble transform Kalman filter(ETKF) methods based on 10 000 observing system simulation experiments on the shallow-water equation model are also provided. The experimental results show that the proposed CNOP–4 DVar method performs better than the CNOP–ETKF method and substantially better than the CNOP method.
基金Supported by the National Natural Science Foundation of China Youth Science Fund Project(Nos.62101405,61372185)
文摘This paper proposed a robust method based on the definition of Mahalanobis distance to track ground moving target. The feature and the geometry of airborne ground moving target tracking systems are studied at first. Based on this feature, the assignment relation of time-nearby target is calculated via Mahalanobis distance, and then the corresponding transformation formula is deduced. The simulation results show the correctness and effectiveness of the proposed method.
基金supported by the Aeronautical Science Foundation of China(ASFC-20135153031ASFC-20135553035ASFC-2017ZC53033)
文摘In laser-guided bomb attacking process,the target indication from the laser target designator is the premise for the bomb to hit the target accurately.Considering the lack of quantitative study of the irradiation area of the laser target designator,this paper,based on the existing aircraft motion model and the laser transmission model,uses two aircraft as respectively the carrier of the laser-guided bomb and the carrier of the laser designator and proposes a method to calculate the global irradiation area of the airborne laser designator.By using the proposed algorithm,the global irradiation area when attacking a large flat target or a large spherical target is simulated respectively.Finally,according to the simulation results,the influences of different factors on the shapes of the irradiation area are discussed in detail.
文摘Objective: to explore the role of medical archiving and communication system in the training of target delineation ability of oncology graduate students and regular training students. Methods: this subject will take the newly admitted graduate students and planning students as the research objects, and senior doctors will use the medical archive and communication system to carry out training on sectional anatomy and target area delineation in the form of department lectures. The application of medical archiving and communication system in improving the ability of target area delineation was explored by self before and after comparison, and the ability of target area delineation was tested before training, after training and three months after graduation. To evaluate the theoretical knowledge and practical operation level of target area delineation in order to explore the superiority and feasibility of medical archiving and communication system in improving the target area delineation ability of oncology graduate students and planning students. Results: there was a statistical difference between the accuracy of target area delineation after relevant knowledge training and three months after graduation by using the medical archive and communication system and before training (P < 0.05). Conclusion: using the medical archive and communication system to train oncology graduate students and training students in relevant knowledge can significantly improve their ability to outline the target area, better adapt to the development of oncology, and lay a solid foundation for becoming a qualified oncologist in the future.
文摘Land use regionalization is a strategic measure for the rational use,management and protection of land resources based on local conditions.Based on the needs of targeted poverty alleviation and rural revitalization strategy and the analysis on the natural and socioeconomic conditions,characteristics of land resources,and the current status of land use in Luquan County,corresponding regionalization indices were selected from four aspects:economic environment conditions,socioeconomic conditions,land resources and land use structure,and poverty alleviation and development level,a scientific and feasible index system for land use regionalization was constructed,and land use in Luquan County was regionalized by using systematic cluster analysis method.The results show that the 16 townships(towns)of Luquan County were divided into four land use regions,poverty alleviation region for development of new town and characteristic industries in the southwest(I),agricultural development and ecological poverty alleviation region in central mountainous area(II),poverty alleviation region for development of characteristic agriculture and tourism towns in eastern plateau mountainous area(III),and poverty alleviation region for development of characteristic industries and protection of land economy in the northern alpine valley area(IV).In addition,suggestions were put forward for the rational use of land in each region.
基金Program for Innovative Research Team in University(IRT520)CAST of China (20090703)
文摘When the space robot captures a floating target, contact impact occurs inevitably and frequently between the manipulator hand and the target, which seriously impacts the position and attitude of the robot and grasping security. ＂Dynamic grasping area＂ is introduced to describe the collision process of manipulator grasping target, and grasping area control equation is established. By analyzing the impact of grasping control parameters, base and target mass on the grasping process and combining the life experience, it is found that if the product of speed control parameter and dB adjustment parameter is close to but smaller than the minimum grasping speed, collision impact in the grasping process could be reduced greatly, and then an ideal grasping strategy is proposed. Simulation results indicate that during the same period, the strategy grasping is superior to the accelerating grasping, in that the amplitude of impact force is reduced to 20%, and the attitude control torque is reduced to 15%, and the impact on the robot is eliminated significantly. The results would have important academic value and engineering significance.
基金supported by the National Natural Science Foundation of China(Grant Nos.41105038and40830955)the NationalKey Technology R&D Program(Grant No.2012BAC22B03)
文摘This study examines the time and regime dependencies of sensitive areas identified by the conditional nonlinear optiflml perturbation （CNOP） method for forecasts of two typhoons. Typhoon Meari （2004） was weakly nonlinear and is herein referred to as the linear case, while Typhoon Matsa （2005） was strongly nonlinear and is herein referred to as the nonlinear case. In the linear case, the sensitive areas identified for special forecast times when the initial time was fixed resembled those identified for other forecast times. Targeted observations deployed to improve a special time forecast would thus also benefit forecasts at other times. In the nonlinear case, the similarities among the sensitive areas identified for different forecast times were more limited. The deployment of targeted observations in the nonlinear case would therefore need to be adapted to achieve large improvements for different targeted forecasts. For both cases, the closer the forecast time, the higher the similarities of the sensitive areas. When the forecast time was fixed, the sensitive areas in the linear case diverged continuously from the verification area as the forecast period lengthened, while those in the nonlinear case were always located around the initial cyclones. The deployment of targeted observations to improve a special forecast depends strongly on the time of deployment. An examination of the efficiency gained by reducing initial errors within the identified sensitive areas confirmed these results. In general, the greatest improvement in a special time forecast was obtained by identifying the sensitive areas for the corresponding forecast time period.
基金supported by the National Natural Science Foundation of the China (Grant Nos 60676009 and 60776034)the Doctor Foundation of Ministry of Education of China (Grant No 20050701015)the National Outstanding Young Scientist Foundation of China (Grant No 60725415)
文摘Repeater optimization is the key for SOC （System on Chip） interconnect delay design. This paper proposes a novel optimal model for minimizing power and area overhead of repeaters while meeting the target performance of on-chip interconnect lines. It also presents Lagrangian function to find the number of repeaters and their sizes required for minimizing area and power overhead with target delay constraint. Based on the 65 nanometre CMOS technology, the computed results of the intermediate and global lines show that the proposed model can significantly reduce area and power of interconnected lines, and the better performance will be achieved with the longer line. The results compared with the reference paper demonstrate the validity of this model. It can be integrated into repeater design methodology and CAD （computer aided design） tool for interconnect planning in nanometre SOC.
文摘Against a background of continuing loss of biodiversity, it is argued that for the successful conservation of threatened plant species we need to ensure the more effective integration of the various conservation actions employed, clarify the wording of the CBD targets and provide clearer operational guidance as to how they are to be implemented and their implementation monitored. The role and effectiveness of protected areas in conserving biodiversity and in particular plant species in situ are discussed as are recent proposals for a massive increase of their extent. The need for much greater effort and investment in the conservation or protection of threatened species outside protected areas where most plant diversity occurs is highlighted. The difficulties involved in implementing effective in situ conservation of plant diversity both at an area-and species/population-based level are discussed. The widespread neglect of species recovery for plants is noted and the desirability of making a clearer distinction between species recovery and reintroduction is emphasized. Key messages from a global overview of species recovery are outlined and recommendations made, including the desirability of each country preparing a national species recovery strategy. The projected impacts of global change on protected areas and on species conservation and recovery, and ways of addressing them are discussed.
基金National Natural Science Foundation of China (10372082) Aeronautical Science Foundation of China (02B53008) and Doctorate Foundation of Northwestern Polytechnical University (CX200301)
文摘Aircraft single-hit vulnerability/survivability is usually expressed as the probability of kill or the vulnerable area in case of being given a random threat （e.g. a fragment） hit on the aircraft. In this paper, introducing the ＂equivalent target method＂ in lethality field into the aircraft vulnerability assessment, a generic vulnerability calculation model is proposed. In order for a good representation of reality, the model considers the threat change of state-of-motion during the threat penetrating into the components successively. Application shows that the proposed generic model has solved the Pk/h （probability of kill given by a hit on the component） calculation problem in aircraft vulnerability assessment, and is easier to be computerized than other commonly used models.
文摘The electromagnetic scattering principles of geological radar targets and various influential factors were discussed, and the importance of researching into the electromagnetic scattering features of the targets to the actual prospecting task was pointed out.
基金Supported by Commissioned Project of Office of Rural Work Leading Group of Kunming Municipal Committee of the Communist Party of China"Study on the Poverty Alleviation Model of Kunming City in the Context of World Poverty Reduction"
文摘Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, as an research case, this article analyzes and summarizes the industry-supporting poverty alleviation achievements and successful experience of two typical relocation areas (Shanhou Village and Eyang Village) in Xundian County. Practice has shown that the key to industry-supporting poverty alleviation lies in targetedness to strengthen the participation of poor farmers in industrial development. The interests of poverty alleviation entities should be linked by market mechanism to establish a benign interaction between all parties for win-win situation, thereby effectively guaranteeing the long-term and healthy development of poverty alleviation by supporting industry.
文摘Taking the Dapingzhang copper-polymetallic deposit in Yunnan Province, China as the research object, the maximum entropy model was used to extract the mining information, and the mineral resource prediction model was established by using the exploration data of the deposit and related regions in this area, so as to determine the prospecting prospect area in the study area. In this paper, the Jacknife analysis module of maximum entropy model is used to quantitatively rank the importance of 39 geochemical element variables, and finally obtain the prospecting prospect map of the study area. The research results show that the Dapingzhang mining area has the potential to find hidden ore in the deep and surrounding areas, and the northern and southern ends and western sides of the rock ore control structural belt in the eastern region of the mining area have good prospecting prospects. The research results provide an important basis for the deployment of follow-up exploration work in the study area, and the maximum entropy model has a good application effect in mineral resources exploration.
文摘In order to find out the various restrictions and difficulties of financial poverty alleviation in rural areas,taking Hubei Province as an example,this paper firstly introduced current situations of financial poverty alleviation in rural areas of Hubei Province. Then,it analyzed problems confronted by financial poverty alleviation in rural areas of Hubei Province:( i) subjects of financial poverty alleviation not mature and poverty alleviation risks increased,( ii) backward agricultural insurance system,( iii) rural credit system not perfect,and( iv) weak guiding policies of financial poverty alleviation. Finally,it came up with pertinent recommendations: improving rural financial environment,actively developing the innovation mode of financial poverty alleviation,and strengthening relevant supervision efforts.
