Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-compl...Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-complexity K-best detection algorithms are proposed. The improved-performance K-best detection algorithm deploys minimum mean square error （MMSE） filtering of a channel matrix before QR decomposition. This algorithm can decrease the probability of excluding the optimum path and achieve better performance. The reducedcomplexity K-best detection algorithms utilize a sphere decoding method to reduce searching constellation points. Simulation results show that the improved performance K-best detection algorithm obtains a 1 dB performance gain compared to the K- best detection algorithm based on sorted QR decomposition （SQRD）. Performance loss occurs when K = 4 in reduced complexity K-best detection algorithms. When K = 8, the reduced complexity K-best detection algorithms require less computational effort compared with traditional K-best detection algorithms and achieve the same performance.展开更多
Objective To evaluate the factors affecting optimal stentt expansion in calcified lesions treated by aggressive plaque modification with rotational atherectomy （RA） and a cutting balloon （CB）. Methods From January...Objective To evaluate the factors affecting optimal stentt expansion in calcified lesions treated by aggressive plaque modification with rotational atherectomy （RA） and a cutting balloon （CB）. Methods From January 2014 to May 2015, 92 patients with moderate to severe coronary calcified lesions underwent rotational atherectomy and intravascular ultrasound imaging at Chinese PLA General Hospital （Beijing, China） were included in this study, They were divided into a rotational artherectomy combined with cutting balloon （RACB） group （46 patients treated with RA followed by CB angioplasty） and an RA group （46 patients treated with RA followed by plain balloon angioplasty）. Another 40 patients with similar severity of their calcified lesions treated with plain old balloon angioplasty （POBA） were de- mographically matched to the other groups and defined as the POBA group. All patients received a drug-eluting stent after plaque prepara- tion. Lumen diameter and lumen diameter stenosis （LDS） were measured by quantitative coronary angiography at baseline, after RA, after dilatation, and after stenting. Optimal stent expansion was defined as the final LDS 〈 10%. Results The initial and post-RA LDS values were similar among the three groups. However, after dilatation, the LDS significantly decreased in the RACB group （from 54.5% ± 8.9% to 36.1%＋ 7.1%） but only moderately decreased （from 55.7% ± 7.8% to 46.9% ± 9.4%） in the RA group （time × group, P 〈 0.001）. After stenting, there was a higher rate of optimal stent expansion in the RACB group （71.7% in the RACB group, 54.5% in the RA group, and 15% in the POBA group, P 〈 0.001）, and the final LDS was significantly diminished in the RACB group compared to the other two groups （6.0% ± 2.3%, 10.8% ± 3.3%, 12.7% ± 2.1%, P 〈 0.001）. Moreover, an LDS 〈 40% after plaque preparation （OR = 2.994, 95% CI： 1.297-6.911） was associated with optimal stent expansion, which also had a positive correlation with the appearance of a calcified ring split （r = 0,581, P 〈 0.001）. Conclusions Aggressive plaque modification with RA and CB achieve more optimal stent expansion. An LDS ≤ 40% after plaque modification was a predictive factor for optimal stent expansion in calcified lesions. This parameter was also associated with the presence of calcified ring split.展开更多
The number of scientific investigations on women＇s football specific to the topics of player characteristics and demands of the game has considerably increased in recent years due to the increased popularity of the w...The number of scientific investigations on women＇s football specific to the topics of player characteristics and demands of the game has considerably increased in recent years due to the increased popularity of the women＇s game worldwide, although they are not yet as numerous as in the case of men＇s football. To date, only two scientific publications have attempted to review the main findings of studies published in this area. However, one of them was published about 20 years ago, when women＇s football was still in its infancy and there were only a few studies to report on. The other review was more recent. Nonetheless, its main focus was on the game and training demands of senior elite female players. Thus, information on female footballers of lower competitive levels and younger age groups was not included. Consequently, an updated review is needed in this area. The present article therefore aims to provide an overview of a series of studies that have been published so far on the specific characteristics of female football players and the demands of match-play. Mean values reported in the literature for age （12-27 years）, body height （155-174 cm）, body mass （48-72 kg）, percent body fat （13%-29%）, maximal oxygen uptake （45.1-55.5 mL/kg/min）, Yo-Yo Intermittent Recovery Test Level l （780-1379 m）, maximum heart rate （189-202 bpm）, 30 m sprint times （4.34-4.96 s）, and counter- movement jump or vertical jump （28-50 cm） vary mostly according to the players＇ competitive level and positional role. There are also some special considerations that coaches and other practitioners should he aware of when working with female athletes such as the menstrual cycle, potential pregnancy and lactation, common injury risks （particularly knee and head injuries） and health concerns （e.g., female athlete triad, iron deficiency, and anemia） that may affect players＇ football performance, health or return to play. Reported mean values for total distance covered （4-13 km）, distance covered at high-speed （0.2-1.7 km）, average/peak heart rate （74%-87%/94%-99% HRmax）, average/peak oxygen uptake （52%-77%/96%-98% VO2max）, and blood lactate （2.2-7.3 mmol/L） during women＇s football match-play vary according to the players＇ competitive level and positional role. Methodological differences may account for the discrepancy of the reported values as well. Finally, this review also aims to identify literature gaps that require further scientific research in women＇s football and to derive a few practical recom-mendations. The information presented in this report provides an objective point of reference about player characteristics and game demands at various levels of women＇s football, which can help coaches and sport scientists to design more effective training programs and science-based strategies for the further improvement of players＇ football performance, health, game standards, and positive image of this sport.展开更多
A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an an...A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an annual meltwater output. The short Aghil glaciers on the contrary are continental, arid and cold. 2). The present-day oscillations of the Karakorum glaciers are related to their own mass, and are contrary to and independent of the actual climate. Only the short glaciers, with steep tongue fronts, show a present-day positive balance. 3). C- dated Late Glacial moraines indicate14 a 400~800 m thick valley glacier at the former confluence point of the K2-, Sarpo Laggo- and Skamri glaciers. 4). From the evidence of transfluence passes with roches moutonnées, striae and the limits of glacial polishing, as well as moraines and erratics, a High Glacial at least 1200 m thick ice-stream network between the Karakorums and the Kuen Lun north slopes was reconstructed. The Shaksgam and Yarkand valleys were occupied by glaciers coming from west Tibet. The lowest-lying moraines are to be found in the foreland down to 2000 m, indicating a depression of the High Glacial (LGM) snowline (ELA) by 1300 m. 5). The approximately 10,000 measurements of the radiation balance at up to heights of 5500 m on K2 indicate that with incoming energy near the solar constant the reflection from snow- covered ice is up to 70% greater than from rock and rock waste surfaces. 6).These results confirm for the very dry western margins of Tibet an almost complete ice sheet cover in an area with subtropical energy balance, conforming with the Ice Age hypothesis of the author which is based upon the presence of a 2.4 million km2 Tibetan inland ice sheet. This inland ice developed for the first time when Tibet was uplifted over the snowline during the early Pleistocene. As the measured subtropical radiation balance shows, it was able to trigger the Quaternary Ice Ages.展开更多
The relationship between the strain rate field observed by GPS and global distribution of strong earthquakes is analyzed in this work. How do we recognize the characteristics of global seismic activities with space ob...The relationship between the strain rate field observed by GPS and global distribution of strong earthquakes is analyzed in this work. How do we recognize the characteristics of global seismic activities with space observation technology? A preliminary model of Cellular Automata that could simulate the global seismic activities both in time and space has been established based on the results of global strain rate field provided by the GSRM Program. The grid of the model is evenly divided,which is consistent with that of GSRM.The status of each cell is its strain state,and is adjusted according to the evolution rules.Maximum shear strain criterion is adopted in the evolution of the Cellular Automata. The threshold for cells in surface expansion is 80% of that for those in compression. The preliminary model could in general simulate the main characteristics of the distribution of the global seismic activities. It could exhibit in general the global distribution of weak and active tectonic activities. Although the preliminary Cellular Automata model needs to be improved in many aspects,the result suggests the possibility of modeling the general features of rather complicated global seismic activities based on the strain rates obtained by GPS and other observations.展开更多
Wavelet decomposition is used to analyze barometric fluctuation and earth tidal response in borehole water level changes. We apply wavelet analysis method to the decomposition of barometric fluctuation and earth tidal...Wavelet decomposition is used to analyze barometric fluctuation and earth tidal response in borehole water level changes. We apply wavelet analysis method to the decomposition of barometric fluctuation and earth tidal response into several temporal series in different frequency ranges. Barometric and tidal coefficients in different frequency ranges are computed with least squares method to remove barometric and tidal response. Comparing this method with general linear regression analysis method, we find wavelet analysis method can efficiently remove barometric and earth tidal response in borehole water level. Wavelet analysis method is based on wave theory and vibration theories. It not only considers the frequency characteristic of the observed data but also the temporal characteristic, and it can get barometric and tidal coefficients in different frequency ranges. This method has definite physical meaning.展开更多
Since 1790, Antarctic living resources were becoming subjects of competition among the exploiters to be first in obtaining the maximum profit from them. This led to subsequent extinction of valuable species from fur s...Since 1790, Antarctic living resources were becoming subjects of competition among the exploiters to be first in obtaining the maximum profit from them. This led to subsequent extinction of valuable species from fur seals and next penguins, large through small whales, industrial demersal fish, further to pelagic species and now toothfish, crabs and krill. Catch proportions of their numerous and biomass decrease. The biomass of South Georgia Icefish estimated for 40 years in spide of decreasing trend has one of the largest components-the oscillations with periods of 3 years or 4 years. Their models explain large biomass fluctuations in the years 1975 to 1981 with amplitudes ±15 × 10^3 tonnes around average 20 ×10^3 tonnes and further decline up to 2005 season with oscillation ±4 ×10^3 tonnes around average 5 × 10^3 tonnes. For future season, 2016 model predicts a little increase of the biomass oscillation at level of 8 × 10^3 tonnes with reduced amplitude 2 × 10^3 tonnes. Slowly increase density of adult fish was also reported for target similar and close related mackerel icefish. Additional references for biomass levels help reduce the risk of further depletion biomass of Pseudochaenichthys georgianus which already declined to 75%. As global warming promote phytoplankton growth, replacing krill fishery by algae farms can save unique Antarctic heritages.展开更多
基金The National High Technology Research and Develop-ment Program of China (863Program)(No.2006AA01Z264)the National Natural Science Foundation of China (No.60572072)
文摘Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-complexity K-best detection algorithms are proposed. The improved-performance K-best detection algorithm deploys minimum mean square error （MMSE） filtering of a channel matrix before QR decomposition. This algorithm can decrease the probability of excluding the optimum path and achieve better performance. The reducedcomplexity K-best detection algorithms utilize a sphere decoding method to reduce searching constellation points. Simulation results show that the improved performance K-best detection algorithm obtains a 1 dB performance gain compared to the K- best detection algorithm based on sorted QR decomposition （SQRD）. Performance loss occurs when K = 4 in reduced complexity K-best detection algorithms. When K = 8, the reduced complexity K-best detection algorithms require less computational effort compared with traditional K-best detection algorithms and achieve the same performance.
文摘Objective To evaluate the factors affecting optimal stentt expansion in calcified lesions treated by aggressive plaque modification with rotational atherectomy （RA） and a cutting balloon （CB）. Methods From January 2014 to May 2015, 92 patients with moderate to severe coronary calcified lesions underwent rotational atherectomy and intravascular ultrasound imaging at Chinese PLA General Hospital （Beijing, China） were included in this study, They were divided into a rotational artherectomy combined with cutting balloon （RACB） group （46 patients treated with RA followed by CB angioplasty） and an RA group （46 patients treated with RA followed by plain balloon angioplasty）. Another 40 patients with similar severity of their calcified lesions treated with plain old balloon angioplasty （POBA） were de- mographically matched to the other groups and defined as the POBA group. All patients received a drug-eluting stent after plaque prepara- tion. Lumen diameter and lumen diameter stenosis （LDS） were measured by quantitative coronary angiography at baseline, after RA, after dilatation, and after stenting. Optimal stent expansion was defined as the final LDS 〈 10%. Results The initial and post-RA LDS values were similar among the three groups. However, after dilatation, the LDS significantly decreased in the RACB group （from 54.5% ± 8.9% to 36.1%＋ 7.1%） but only moderately decreased （from 55.7% ± 7.8% to 46.9% ± 9.4%） in the RA group （time × group, P 〈 0.001）. After stenting, there was a higher rate of optimal stent expansion in the RACB group （71.7% in the RACB group, 54.5% in the RA group, and 15% in the POBA group, P 〈 0.001）, and the final LDS was significantly diminished in the RACB group compared to the other two groups （6.0% ± 2.3%, 10.8% ± 3.3%, 12.7% ± 2.1%, P 〈 0.001）. Moreover, an LDS 〈 40% after plaque preparation （OR = 2.994, 95% CI： 1.297-6.911） was associated with optimal stent expansion, which also had a positive correlation with the appearance of a calcified ring split （r = 0,581, P 〈 0.001）. Conclusions Aggressive plaque modification with RA and CB achieve more optimal stent expansion. An LDS ≤ 40% after plaque modification was a predictive factor for optimal stent expansion in calcified lesions. This parameter was also associated with the presence of calcified ring split.
文摘The number of scientific investigations on women＇s football specific to the topics of player characteristics and demands of the game has considerably increased in recent years due to the increased popularity of the women＇s game worldwide, although they are not yet as numerous as in the case of men＇s football. To date, only two scientific publications have attempted to review the main findings of studies published in this area. However, one of them was published about 20 years ago, when women＇s football was still in its infancy and there were only a few studies to report on. The other review was more recent. Nonetheless, its main focus was on the game and training demands of senior elite female players. Thus, information on female footballers of lower competitive levels and younger age groups was not included. Consequently, an updated review is needed in this area. The present article therefore aims to provide an overview of a series of studies that have been published so far on the specific characteristics of female football players and the demands of match-play. Mean values reported in the literature for age （12-27 years）, body height （155-174 cm）, body mass （48-72 kg）, percent body fat （13%-29%）, maximal oxygen uptake （45.1-55.5 mL/kg/min）, Yo-Yo Intermittent Recovery Test Level l （780-1379 m）, maximum heart rate （189-202 bpm）, 30 m sprint times （4.34-4.96 s）, and counter- movement jump or vertical jump （28-50 cm） vary mostly according to the players＇ competitive level and positional role. There are also some special considerations that coaches and other practitioners should he aware of when working with female athletes such as the menstrual cycle, potential pregnancy and lactation, common injury risks （particularly knee and head injuries） and health concerns （e.g., female athlete triad, iron deficiency, and anemia） that may affect players＇ football performance, health or return to play. Reported mean values for total distance covered （4-13 km）, distance covered at high-speed （0.2-1.7 km）, average/peak heart rate （74%-87%/94%-99% HRmax）, average/peak oxygen uptake （52%-77%/96%-98% VO2max）, and blood lactate （2.2-7.3 mmol/L） during women＇s football match-play vary according to the players＇ competitive level and positional role. Methodological differences may account for the discrepancy of the reported values as well. Finally, this review also aims to identify literature gaps that require further scientific research in women＇s football and to derive a few practical recom-mendations. The information presented in this report provides an objective point of reference about player characteristics and game demands at various levels of women＇s football, which can help coaches and sport scientists to design more effective training programs and science-based strategies for the further improvement of players＇ football performance, health, game standards, and positive image of this sport.
文摘A modern research approach and working techniques in hitherto unexamined areas, produced the following results: 1). The tongues of deca- kilometre long Karakorum glaciers belong to temperate ice-streams with an annual meltwater output. The short Aghil glaciers on the contrary are continental, arid and cold. 2). The present-day oscillations of the Karakorum glaciers are related to their own mass, and are contrary to and independent of the actual climate. Only the short glaciers, with steep tongue fronts, show a present-day positive balance. 3). C- dated Late Glacial moraines indicate14 a 400~800 m thick valley glacier at the former confluence point of the K2-, Sarpo Laggo- and Skamri glaciers. 4). From the evidence of transfluence passes with roches moutonnées, striae and the limits of glacial polishing, as well as moraines and erratics, a High Glacial at least 1200 m thick ice-stream network between the Karakorums and the Kuen Lun north slopes was reconstructed. The Shaksgam and Yarkand valleys were occupied by glaciers coming from west Tibet. The lowest-lying moraines are to be found in the foreland down to 2000 m, indicating a depression of the High Glacial (LGM) snowline (ELA) by 1300 m. 5). The approximately 10,000 measurements of the radiation balance at up to heights of 5500 m on K2 indicate that with incoming energy near the solar constant the reflection from snow- covered ice is up to 70% greater than from rock and rock waste surfaces. 6).These results confirm for the very dry western margins of Tibet an almost complete ice sheet cover in an area with subtropical energy balance, conforming with the Ice Age hypothesis of the author which is based upon the presence of a 2.4 million km2 Tibetan inland ice sheet. This inland ice developed for the first time when Tibet was uplifted over the snowline during the early Pleistocene. As the measured subtropical radiation balance shows, it was able to trigger the Quaternary Ice Ages.
基金sponsored by the National Key Techonology R&D Program(2012BAK19B01)the National Natural Foundation of China(41274098)
文摘The relationship between the strain rate field observed by GPS and global distribution of strong earthquakes is analyzed in this work. How do we recognize the characteristics of global seismic activities with space observation technology? A preliminary model of Cellular Automata that could simulate the global seismic activities both in time and space has been established based on the results of global strain rate field provided by the GSRM Program. The grid of the model is evenly divided,which is consistent with that of GSRM.The status of each cell is its strain state,and is adjusted according to the evolution rules.Maximum shear strain criterion is adopted in the evolution of the Cellular Automata. The threshold for cells in surface expansion is 80% of that for those in compression. The preliminary model could in general simulate the main characteristics of the distribution of the global seismic activities. It could exhibit in general the global distribution of weak and active tectonic activities. Although the preliminary Cellular Automata model needs to be improved in many aspects,the result suggests the possibility of modeling the general features of rather complicated global seismic activities based on the strain rates obtained by GPS and other observations.
基金The research was jointly supported by National NatureScience Foundation of China (40374019)the research subject entitled"Research on the Digital Data Analysis and Application of Underground Fluid" under the 11th Five-Year Program of China Earthquake Administration(2006BAC01B02-03-02)
文摘Wavelet decomposition is used to analyze barometric fluctuation and earth tidal response in borehole water level changes. We apply wavelet analysis method to the decomposition of barometric fluctuation and earth tidal response into several temporal series in different frequency ranges. Barometric and tidal coefficients in different frequency ranges are computed with least squares method to remove barometric and tidal response. Comparing this method with general linear regression analysis method, we find wavelet analysis method can efficiently remove barometric and earth tidal response in borehole water level. Wavelet analysis method is based on wave theory and vibration theories. It not only considers the frequency characteristic of the observed data but also the temporal characteristic, and it can get barometric and tidal coefficients in different frequency ranges. This method has definite physical meaning.
文摘Since 1790, Antarctic living resources were becoming subjects of competition among the exploiters to be first in obtaining the maximum profit from them. This led to subsequent extinction of valuable species from fur seals and next penguins, large through small whales, industrial demersal fish, further to pelagic species and now toothfish, crabs and krill. Catch proportions of their numerous and biomass decrease. The biomass of South Georgia Icefish estimated for 40 years in spide of decreasing trend has one of the largest components-the oscillations with periods of 3 years or 4 years. Their models explain large biomass fluctuations in the years 1975 to 1981 with amplitudes ±15 × 10^3 tonnes around average 20 ×10^3 tonnes and further decline up to 2005 season with oscillation ±4 ×10^3 tonnes around average 5 × 10^3 tonnes. For future season, 2016 model predicts a little increase of the biomass oscillation at level of 8 × 10^3 tonnes with reduced amplitude 2 × 10^3 tonnes. Slowly increase density of adult fish was also reported for target similar and close related mackerel icefish. Additional references for biomass levels help reduce the risk of further depletion biomass of Pseudochaenichthys georgianus which already declined to 75%. As global warming promote phytoplankton growth, replacing krill fishery by algae farms can save unique Antarctic heritages.
