According to the freely linear Rossby wave theory, global 1°×1°climatology of Rossby deformation radius and phase speed are studied under the fiat bottom fluid approximation. Geographical variations in ...According to the freely linear Rossby wave theory, global 1°×1°climatology of Rossby deformation radius and phase speed are studied under the fiat bottom fluid approximation. Geographical variations in the contours of the phase speed are very similar to those of the Rossby radius of formation, which are mainly affected by stratification, rotation, water depth, topography, etc. The basin-crossing time of the first baroclinic Rossby wave is obtained and analyzed in the global ocean basins. The results are useful to learn the importance of Rosaby wave and the adiabatic adjustment of large-scale ocean circulation.展开更多
Background: Obstacle crossing is the common reason of falling in older adults. Anticipatory postural adjustments phase (APAP) and reaction time phase (RTP) are two important factors in falling prediction. According to...Background: Obstacle crossing is the common reason of falling in older adults. Anticipatory postural adjustments phase (APAP) and reaction time phase (RTP) are two important factors in falling prediction. According to previous studies, these parameters increase in older adults at high risk falling. This study explored the effect of aging on APAP and RTP in obstacle negotiation. Method: Nineteen older adults (mean age: 66.73 ± 3.38 years) and twelve young adults (mean age: 26.5 ± 4.37 years), participated in this study. Participants take part in gait initiation task from a starting position on a force platform under two conditions, unobstructed and obstructed (obstacle placed at 1 m from the initial position). RTP and APAP were measured and Timed “Up” & “Go” test (TUG) as a functional test, recorded for all participants. Results: There was no significant difference between healthy young and older adults in RTP and APAP in the unobstructed and obstructed conditions. TUG test was the most sensitive indicator of falling between two groups. Conclusion: Information processing capacity for motor planning and proper strategy selection in pre crossing phase of obstacle negotiation did not have significant difference in healthy old and young groups. Maybe in respect to select healthy older adults without any neurological disorders and cognitive impairments, low attention demand of well learned walking and obstacle negotiation tasks, lead to perform both postural task more automatically and without any significant difference detection.展开更多
Due to the limited transmission resources for data relay in the tracking and data relay satellite system (TDRSS), there are many job requirements in busy days which will be discarded in the conventional job scheduli...Due to the limited transmission resources for data relay in the tracking and data relay satellite system (TDRSS), there are many job requirements in busy days which will be discarded in the conventional job scheduling model. Therefore, the improvement of scheduling efficiency in the TDRSS can not only help to increase the resource utilities, but also to reduce the scheduling failure ratio. A model of nonhomogeneous parallel machines scheduling problems with time window (NPM-TW) is firstly built up for the TDRSS, considering the distinct features of the variable preparation time and the nonhomogeneous transmission rates for different types of antennas on each tracking and data relay satellite (TDRS). Then, an adaptive subsequence adjustment (ASA) framework with evolutionary asymmetric path-relinking (EvAPR) is proposed to solve this problem, in which an asymmetric progressive crossover operation is involved to overcome the local optima by the conventional job inserting methods. The numerical results show that, compared with the classical greedy randomized adaptive search procedure (GRASP) algorithm, the scheduling failure ratio of jobs can be reduced over 11% on average by the proposed ASA with EvAPR.展开更多
In order to achieve dynamical optimization of mobility load balancing,we analyze the conflict between mobility load balancing and mobility robustness optimization caused by the improper operation of handover parameter...In order to achieve dynamical optimization of mobility load balancing,we analyze the conflict between mobility load balancing and mobility robustness optimization caused by the improper operation of handover parameters.To this end,a method of Handover Parameters Adjustment for Conflict Avoidance(HPACA)is proposed.Considering the movement of users,HPCAC can dynamically adjust handover range to optimize the mobility load balancing.The movement of users is an important factor of handover,which has a dramatic impact on system performance.The numerical evaluation results show the proposed approach outperforms the existing method in terms of throughput,call blocking ratio,load balancing index,radio link failure ratio,ping-pong handover ratio and call dropping ratio.展开更多
By considering economic strength and economic profit of insurance company, this paper presents a concept-contact point, and gives premium expectation adjust-time model which provides more practical significance for in...By considering economic strength and economic profit of insurance company, this paper presents a concept-contact point, and gives premium expectation adjust-time model which provides more practical significance for insurance company to make rational adjustment of premium. Finally, an illustration is given to show their application.展开更多
目的分析1990—2019亚洲主要国家及全球宫颈癌疾病负担,为制定宫颈癌防控策略提供科学依据。方法收集1990—2019年全球疾病负担研究(global burden of disease,GBD)数据,利用发病、死亡、伤残调整寿命年(disability-adjusted life years...目的分析1990—2019亚洲主要国家及全球宫颈癌疾病负担,为制定宫颈癌防控策略提供科学依据。方法收集1990—2019年全球疾病负担研究(global burden of disease,GBD)数据,利用发病、死亡、伤残调整寿命年(disability-adjusted life years,DALY)等指标定量评估宫颈癌的疾病负担情况,采用估计百分百变化(estimated annual percent change,EAPC)分析疾病负担时间变化趋势。结果1990—2019年,全球宫颈癌标化发病率从7.64/10万下降至6.81/10万,标化死亡率从4.46/10万降低至3.40/10万,标化DALY率从139.98/10万下降至107.20/10万,年平均降低分别为0.39%、0.96%、0.94%(EAPC<0,P<0.05)。亚洲主要国家中,中国的标化发病率从4.20/10万上升至5.53/10万,平均每年增长1.63%(EAPC>0,P>0.05)。中国宫颈癌的死亡数从2.64万增加到5.34万,相对增长1.02倍,全球及亚洲主要国家标化死亡率、标化DALY率均呈逐年下降趋势,而中国未出现下降趋势。相关分析显示,发病率与社会人口指数(socio-demographic index,SDI)无明显相关性(ρ=-0.13,P=0.11),死亡率与SDI呈负相关(ρ=-0.74,P<0.001),DALY与SDI也呈负相关(ρ=-0.77,P<0.001)。结论中国宫颈癌的标化发病率、死亡率逐年增加,疾病负担呈上升趋势,应积极采取科学有效的防控措施,降低宫颈癌疾病负担。展开更多
基金This study was supported by the National Natural Science Foundation of China under contract No.40576020the Youth Innovative Foundation Project of Polar Reasearch Institute of China under contract No.J0D 200601.
文摘According to the freely linear Rossby wave theory, global 1°×1°climatology of Rossby deformation radius and phase speed are studied under the fiat bottom fluid approximation. Geographical variations in the contours of the phase speed are very similar to those of the Rossby radius of formation, which are mainly affected by stratification, rotation, water depth, topography, etc. The basin-crossing time of the first baroclinic Rossby wave is obtained and analyzed in the global ocean basins. The results are useful to learn the importance of Rosaby wave and the adiabatic adjustment of large-scale ocean circulation.
文摘Background: Obstacle crossing is the common reason of falling in older adults. Anticipatory postural adjustments phase (APAP) and reaction time phase (RTP) are two important factors in falling prediction. According to previous studies, these parameters increase in older adults at high risk falling. This study explored the effect of aging on APAP and RTP in obstacle negotiation. Method: Nineteen older adults (mean age: 66.73 ± 3.38 years) and twelve young adults (mean age: 26.5 ± 4.37 years), participated in this study. Participants take part in gait initiation task from a starting position on a force platform under two conditions, unobstructed and obstructed (obstacle placed at 1 m from the initial position). RTP and APAP were measured and Timed “Up” & “Go” test (TUG) as a functional test, recorded for all participants. Results: There was no significant difference between healthy young and older adults in RTP and APAP in the unobstructed and obstructed conditions. TUG test was the most sensitive indicator of falling between two groups. Conclusion: Information processing capacity for motor planning and proper strategy selection in pre crossing phase of obstacle negotiation did not have significant difference in healthy old and young groups. Maybe in respect to select healthy older adults without any neurological disorders and cognitive impairments, low attention demand of well learned walking and obstacle negotiation tasks, lead to perform both postural task more automatically and without any significant difference detection.
基金supported by the National Natural Science Foundation of China(6113200291338101+3 种基金91338108)the National S&T Major Project(2011ZX03004-001-01)the Research Fund of Tsinghua University(2011Z05117)the Co-innovation Laboratory of Aerospace Broadband Network Technology
文摘Due to the limited transmission resources for data relay in the tracking and data relay satellite system (TDRSS), there are many job requirements in busy days which will be discarded in the conventional job scheduling model. Therefore, the improvement of scheduling efficiency in the TDRSS can not only help to increase the resource utilities, but also to reduce the scheduling failure ratio. A model of nonhomogeneous parallel machines scheduling problems with time window (NPM-TW) is firstly built up for the TDRSS, considering the distinct features of the variable preparation time and the nonhomogeneous transmission rates for different types of antennas on each tracking and data relay satellite (TDRS). Then, an adaptive subsequence adjustment (ASA) framework with evolutionary asymmetric path-relinking (EvAPR) is proposed to solve this problem, in which an asymmetric progressive crossover operation is involved to overcome the local optima by the conventional job inserting methods. The numerical results show that, compared with the classical greedy randomized adaptive search procedure (GRASP) algorithm, the scheduling failure ratio of jobs can be reduced over 11% on average by the proposed ASA with EvAPR.
基金supported by the National Natural Science Foundation of China under Grant No.61071118the National Basic Research Program of China(973 Program)under Grant No.2012CB316004+1 种基金Special Fund of Chongqing Key Laboratory(CSTC)Chongqing Municipal Education Commission’s Science and Technology Research Project under Grant No.KJ111506
文摘In order to achieve dynamical optimization of mobility load balancing,we analyze the conflict between mobility load balancing and mobility robustness optimization caused by the improper operation of handover parameters.To this end,a method of Handover Parameters Adjustment for Conflict Avoidance(HPACA)is proposed.Considering the movement of users,HPCAC can dynamically adjust handover range to optimize the mobility load balancing.The movement of users is an important factor of handover,which has a dramatic impact on system performance.The numerical evaluation results show the proposed approach outperforms the existing method in terms of throughput,call blocking ratio,load balancing index,radio link failure ratio,ping-pong handover ratio and call dropping ratio.
文摘By considering economic strength and economic profit of insurance company, this paper presents a concept-contact point, and gives premium expectation adjust-time model which provides more practical significance for insurance company to make rational adjustment of premium. Finally, an illustration is given to show their application.
文摘目的分析1990—2019亚洲主要国家及全球宫颈癌疾病负担,为制定宫颈癌防控策略提供科学依据。方法收集1990—2019年全球疾病负担研究(global burden of disease,GBD)数据,利用发病、死亡、伤残调整寿命年(disability-adjusted life years,DALY)等指标定量评估宫颈癌的疾病负担情况,采用估计百分百变化(estimated annual percent change,EAPC)分析疾病负担时间变化趋势。结果1990—2019年,全球宫颈癌标化发病率从7.64/10万下降至6.81/10万,标化死亡率从4.46/10万降低至3.40/10万,标化DALY率从139.98/10万下降至107.20/10万,年平均降低分别为0.39%、0.96%、0.94%(EAPC<0,P<0.05)。亚洲主要国家中,中国的标化发病率从4.20/10万上升至5.53/10万,平均每年增长1.63%(EAPC>0,P>0.05)。中国宫颈癌的死亡数从2.64万增加到5.34万,相对增长1.02倍,全球及亚洲主要国家标化死亡率、标化DALY率均呈逐年下降趋势,而中国未出现下降趋势。相关分析显示,发病率与社会人口指数(socio-demographic index,SDI)无明显相关性(ρ=-0.13,P=0.11),死亡率与SDI呈负相关(ρ=-0.74,P<0.001),DALY与SDI也呈负相关(ρ=-0.77,P<0.001)。结论中国宫颈癌的标化发病率、死亡率逐年增加,疾病负担呈上升趋势,应积极采取科学有效的防控措施,降低宫颈癌疾病负担。