The paper presents a new way to capture the multi-peaks of financial dates,which is the nonparametric kernel density estimation with weishted samples.The new way captures the characters of multi-peaks and clusters of ...The paper presents a new way to capture the multi-peaks of financial dates,which is the nonparametric kernel density estimation with weishted samples.The new way captures the characters of multi-peaks and clusters of financial dates to be facility than the ARCH class and mixture distributions models.For example,we find evidences for the multi-peaks of the dynamical structures of stock index in shanghai stock market and some individual stocks.Monte Carlo simulations indicate the weights are important to describe returns which are mixture distributions.展开更多
A novel interleaving based selected mapping （SLM） scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spa...A novel interleaving based selected mapping （SLM） scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spanning only a few bits are used to produce multiple sequences representing the same information, and one of the sequences resulting in the lowest peak-to-average power ratio （PAPR） is selected for transmission. The implementation of the scheme including the structure of the short-span interleaver is illustrated. The performance of this PAPR reduction scheme is investigated by simulations. This scheme exhibits a good PAPR reduction performance, and for signals of high level modulation, such as 16QAM and 64QAM, it approaches the best performance of all SLM schemes. Compared to the conventional interleaving SLM, this short-span interleaving SLM results in a very short time delay, requires very few register units for buffering, and can be easily implemented by hardware.展开更多
Spring snowmelt peak flow （SSPF） can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by ...Spring snowmelt peak flow （SSPF） can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the SSPF. This study used path analysis with a selection of five factors - the antecedent precipitation index （API）, spring precipitation （SP）, winter precipitation as snowfall （WS）, 〈0℃ temperature accumulation in winter （[ATNI）, and average 〉0℃temperature accumulation in spring （AT） - to analyze their influences on the SSPF in the Kaidu River in Xinjiang, China. The results show that {ATN}, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of[ATN] on SSPF is indirect through WS and AT. The indirect influence of [ATN[ on SSPF through WS accounts for 69% of the total influence of [ATN] on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.展开更多
To reveal the mechanism of control of the Woolly Apple Aphid （Eriosoma lanigerum Hausm, WAA） by increase of biodiversity in the apple orchard, a consecutive two-year field trials were conducted in Yurman province, C...To reveal the mechanism of control of the Woolly Apple Aphid （Eriosoma lanigerum Hausm, WAA） by increase of biodiversity in the apple orchard, a consecutive two-year field trials were conducted in Yurman province, China. The results showed that the peak of natural enemy density curve in the cover cropping orchard was well temporally synchronized with that of the WAA density on trees, but did not synchronize with that of WAA density on trees in clean orchard. In addition, the frequency of natural enemies and WAA within a same sample in cover cropping orchard was obviously higher than that in clean cultivated orchard during the peak of population curves, indicating that natural enemies spatially synchronized with aphids. The density of WAA for the whole growing season in cover cropping orchard was much less than that in clean orchard. Therefore, the temporal-spatial synchrony of natural enemy and aphid populations was proposed as one of the mechanisms for aphid control in cover cropped orchards.展开更多
One of the requirements for modem production machine is versatility and easy reconfiguration to produce new products. The production machines use fixed gearing and mechanical cams in history. The cams were used for sp...One of the requirements for modem production machine is versatility and easy reconfiguration to produce new products. The production machines use fixed gearing and mechanical cams in history. The cams were used for specific stokes and cam switches were used for commissioning of technological process. This solution has disadvantages in lower production speed and no flexibility of production. This article summaries practical steps for machine modernization and highlight practical problems in modernization of older production machine. The electronic cam with direct linear drive was used for traversal motion with high peak acceleration. This paper discusses cam stoke curve design, redesign and fitting.展开更多
文摘The paper presents a new way to capture the multi-peaks of financial dates,which is the nonparametric kernel density estimation with weishted samples.The new way captures the characters of multi-peaks and clusters of financial dates to be facility than the ARCH class and mixture distributions models.For example,we find evidences for the multi-peaks of the dynamical structures of stock index in shanghai stock market and some individual stocks.Monte Carlo simulations indicate the weights are important to describe returns which are mixture distributions.
文摘A novel interleaving based selected mapping （SLM） scheme to depress the relatively high peak power of transmit signals in multicarrier communications is proposed. In the scheme, a group of bit-level interleavers spanning only a few bits are used to produce multiple sequences representing the same information, and one of the sequences resulting in the lowest peak-to-average power ratio （PAPR） is selected for transmission. The implementation of the scheme including the structure of the short-span interleaver is illustrated. The performance of this PAPR reduction scheme is investigated by simulations. This scheme exhibits a good PAPR reduction performance, and for signals of high level modulation, such as 16QAM and 64QAM, it approaches the best performance of all SLM schemes. Compared to the conventional interleaving SLM, this short-span interleaving SLM results in a very short time delay, requires very few register units for buffering, and can be easily implemented by hardware.
基金financially supported by the Project of State Key Basic R & D Program of China (973 Program, Grant No. 2010CB951002)the key deployment project of Chinese Academy of Sciences (Grant No. KZZD-EW-12-2)Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (Grant No. 2011T2Z40)
文摘Spring snowmelt peak flow （SSPF） can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the SSPF. This study used path analysis with a selection of five factors - the antecedent precipitation index （API）, spring precipitation （SP）, winter precipitation as snowfall （WS）, 〈0℃ temperature accumulation in winter （[ATNI）, and average 〉0℃temperature accumulation in spring （AT） - to analyze their influences on the SSPF in the Kaidu River in Xinjiang, China. The results show that {ATN}, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of[ATN] on SSPF is indirect through WS and AT. The indirect influence of [ATN[ on SSPF through WS accounts for 69% of the total influence of [ATN] on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.
文摘To reveal the mechanism of control of the Woolly Apple Aphid （Eriosoma lanigerum Hausm, WAA） by increase of biodiversity in the apple orchard, a consecutive two-year field trials were conducted in Yurman province, China. The results showed that the peak of natural enemy density curve in the cover cropping orchard was well temporally synchronized with that of the WAA density on trees, but did not synchronize with that of WAA density on trees in clean orchard. In addition, the frequency of natural enemies and WAA within a same sample in cover cropping orchard was obviously higher than that in clean cultivated orchard during the peak of population curves, indicating that natural enemies spatially synchronized with aphids. The density of WAA for the whole growing season in cover cropping orchard was much less than that in clean orchard. Therefore, the temporal-spatial synchrony of natural enemy and aphid populations was proposed as one of the mechanisms for aphid control in cover cropped orchards.
文摘One of the requirements for modem production machine is versatility and easy reconfiguration to produce new products. The production machines use fixed gearing and mechanical cams in history. The cams were used for specific stokes and cam switches were used for commissioning of technological process. This solution has disadvantages in lower production speed and no flexibility of production. This article summaries practical steps for machine modernization and highlight practical problems in modernization of older production machine. The electronic cam with direct linear drive was used for traversal motion with high peak acceleration. This paper discusses cam stoke curve design, redesign and fitting.
