The annual highest water level of Taihu Lake （Zm） is very significant for flood management in the Taihu Basin. This paper first describes the inter-annual and intra-annual traits of Zm from 1956 to 2000. Then, using...The annual highest water level of Taihu Lake （Zm） is very significant for flood management in the Taihu Basin. This paper first describes the inter-annual and intra-annual traits of Zm from 1956 to 2000. Then, using the Mann-Kenall （MK） and Spearman （SP） nonparametric tests, the long-term change trends of area precipitation and pan evaporation in the Taihu Basin are determined. Meanwhile, using the Morlet wavelet transformation, the fluctuation patterns and change points of precipitation and pan evaporation are analyzed. Also, human activities in the Taihu Basin are described, including land use change and hydraulic project construction. Finally, the relationship between Zm, the water level of Taihu Lake 30 days prior to the day of Zm （Z0）, and the 30-day total precipitation and pan evaporation prior to the day of Zm （P and E0, respectively） is described based on multi-linear regression equations. The relative influence of climate change and human activities on the change of Zm is quantitatively ascertained. The results demonstrate that： （1） Zm was distinctly higher during the 1980-2000 period than during the 1956-1979 period, and the 30 days prior to the day of Zm are the key phase influencing Zm every year; （2） P increased significantly at a confidence level of 95% during the 1956-2000 period, while the reverse was true for E0; （3） The relationship between Zm, P and E0 distinctly changed after 1980; （4） Climate change and human activities together caused frequent occurrences of high Zm after 1980; （5） Climate change caused a substantially greater Zm difference between the 1956-1979 and 1980-2000 periods than human activities. Climate change, as represented by P and E0, was the dominant factor raising Zm, with a relative influence ratio of 83.6%, while human activities had a smaller influence ratio of 16.4%.展开更多
The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “gre...The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “greatest lake period” may be inferred by the last highest lake shorelines. They are several, even tens times larger than that at present. According to the analyses of tens of lakes on the Plateau, most dating data fell into the range of 40-25 ka BP, some lasted to 20 ka BP. It was corresponded to the stage 3 of marine isotope and interstitial of last glaciation. The occurrence of maximum areas of lakes marked the very humid period on the Plateau and was also related to the stronger summer monsoon during that period.展开更多
The distribution of 0 and 1 is studied in the highest level a e-1of primitive sequences over Z/(2\+e). It is proved that the proportion of 0 (or 1) in one period of a e-1is between 40% and 60% for e≥8.
Let y be a generalized Kac-Moody algebra with an integral Borcherds-Cartan matrix. In this paper, we define a d-type weak quantum generalized Kac-Moody algebra wUq^d（y）, which is a weak Hopf algebra. We also study t...Let y be a generalized Kac-Moody algebra with an integral Borcherds-Cartan matrix. In this paper, we define a d-type weak quantum generalized Kac-Moody algebra wUq^d（y）, which is a weak Hopf algebra. We also study the highest weight module over the weak quantum algebra wUdq^d（y） and weak A-forms of wUq^d（y）.展开更多
CNKI has published the ＂Annual Report for International Citation of Chinese Academic Journals＂ since 2012. In the past three years, it has provided comprehensive data on the international impact of Chinese academic ...CNKI has published the ＂Annual Report for International Citation of Chinese Academic Journals＂ since 2012. In the past three years, it has provided comprehensive data on the international impact of Chinese academic journals. Using the clout index （CI） to rank the Chinese academic journals, ＂the Highest International Impact Academic Journals of China＂ and ＂ the Excellent International Impact Academic Journals of China＂ are announced every year. By introducing the rating criteria of the ＂Annual Report for International Citation of Chinese Academic Journals＂, the characteristics of high impact journals are discussed. Especially, the status of the pharmaceutical journals is discussed. We found that there are increasing numbers of Chinese journals that are included in the SCI, and some of them are high impact journals. However, journals published in Chinese are still facing difficulties to be included in SCI, even though they show higher impact than journals published in other non-English languages. The Chinese Pharmaceutical journals need to enhance their international impact, but Journals on Chinese Medicine show high impact.展开更多
In this paper,we prove that the electrical Lie algebra e D_(5)is isomorphic to the semidirect product of sp_(4)and a 2-step nilpotent Lie algebra.Furthermore,we classify the irreducible highest weight modules for e D_...In this paper,we prove that the electrical Lie algebra e D_(5)is isomorphic to the semidirect product of sp_(4)and a 2-step nilpotent Lie algebra.Furthermore,we classify the irreducible highest weight modules for e D_(5).展开更多
The distribution of 0 and 1 is studied in the highest level ae-1, of primitive sequences over . / (2(?) ), and the upper and lower bounds on the ratio of the number of 0 to the number of 1 in one period of ae-1 are ob...The distribution of 0 and 1 is studied in the highest level ae-1, of primitive sequences over . / (2(?) ), and the upper and lower bounds on the ratio of the number of 0 to the number of 1 in one period of ae-1 are obtained. It is revealed that the larger e is, the closer to 1 the ratio will be.展开更多
Decision-theoretic interval estimation requires the use of loss functions that, typically, take into account the size and the coverage of the sets. We here consider the class of monotone loss functions that, under qui...Decision-theoretic interval estimation requires the use of loss functions that, typically, take into account the size and the coverage of the sets. We here consider the class of monotone loss functions that, under quite general conditions, guarantee Bayesian optimality of highest posterior probability sets. We focus on three specific families of monotone losses, namely the linear, the exponential and the rational losses whose difference consists in the way the sizes of the sets are penalized. Within the standard yet important set-up of a normal model we propose: 1) an optimality analysis, to compare the solutions yielded by the alternative classes of losses;2) a regret analysis, to evaluate the additional loss of standard non-optimal intervals of fixed credibility. The article uses an application to a clinical trial as an illustrative example.展开更多
Based on data from palynology, paleosols, paleolimnology, ice core, archeology, sea levels, etc. , we reconstructed climates and environments of the Holocene Megathermal maximum (7. 2-6. 0 ka B. P. ), particularly veg...Based on data from palynology, paleosols, paleolimnology, ice core, archeology, sea levels, etc. , we reconstructed climates and environments of the Holocene Megathermal maximum (7. 2-6. 0 ka B. P. ), particularly vegetation zones, temperatures, precipitation and sea-level fluctuations. Annual mean temperature during that period was estimated at 1 ℃ higher than today for South China, 2 ℃ higher for the Changjiang River Valley, about 3℃ higher for North China, Northeast China and Northwest China and up to 4 - 5 ℃ higher for southern Qinghai-Xizang Plateau. Relative winter temperatures increased much more than average annual temperatures. The centennial-scale warming was accompanied by the expansion of summer monsoon and recession of winter cold currents as well as northward and westward shift of vegetation zones. Higher lake levels registered in all inland lakes of Inner Mongolia, Xinjiang, Qinghai and Xizang indicated that precipitation increased to a certain extent. The Holocene highest sea level in East China about 1 -3 m higher than today, occurred within 6. 5 and 5. 0 kaB. P. and sea water covered coastal areas of about 7×104 km2, which was the Holocene greatest scope of transgression.展开更多
C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface...C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface area（345 m^2/g） and large mesopore size（ca. 4.2 nm）, capable of offering more accessible active sites as well as faster mass transfer for catalysis. Besides, the doping of C（2.21%, molar fraction） at the O sites in Nb2O5 lattice greatly enhanced visible-light response by lowering the band gap, thereby making the material a photocatalyst under visible-light irradiation. Typically, the C-doped Nb2O5 exhibited a high H2 evolution rate of ca. 39.10·μmol·g^-1·h^-1 and also degraded RhB dye completely after 30 min of visible light exposure, which turned out to be much better than Degussa P25 and pure Nb2O5 catalysts.展开更多
Let F be an algebraically closed field and charF=0. In this note, using the method ofmixed product in ref. [1], the irreducible positive （negative） Z-graded module of Liesuperalgebra H（n） with base space V （top s...Let F be an algebraically closed field and charF=0. In this note, using the method ofmixed product in ref. [1], the irreducible positive （negative） Z-graded module of Liesuperalgebra H（n） with base space V （top space V） is determined, where the highest weightof H（n）<sub>0</sub>-module V is not kλ<sub>1</sub> for any nonnegative integer k.展开更多
In this paper, an interpolation polynomial operator F n(f; l,x) is constructed based on the zeros of a kind of Jacobi polynomials as the interpolation nodes. For any continuous function f(x)∈C b [-1,1] ...In this paper, an interpolation polynomial operator F n(f; l,x) is constructed based on the zeros of a kind of Jacobi polynomials as the interpolation nodes. For any continuous function f(x)∈C b [-1,1] (0≤b≤l) F n(f; l,x) converges to f(x) uniformly, where l is an odd number.展开更多
Using new combinatorics of Young walls,we give a new construction of the arbitrary level highest weight crystal B(λ)for the quantum affine algebras of types A^((2))_(2n),D^((2))_(n+1),A^((2))_(2n−1),D^((1))_(n),B^((1...Using new combinatorics of Young walls,we give a new construction of the arbitrary level highest weight crystal B(λ)for the quantum affine algebras of types A^((2))_(2n),D^((2))_(n+1),A^((2))_(2n−1),D^((1))_(n),B^((1))_(n) and C^((1))_(n).We show that the crystal consisting of reduced Young walls is isomorphic to the crystal B(λ).Moreover,we provide a new realization of the crystal B(∞)in terms of reduced virtual Young walls and reduced extended Young walls.展开更多
The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vect...The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vectors of the Verma modules.The simple highest weight module is isomorphic to either that for the symplectic Lie algebra sp4 or Verma module.展开更多
“Often,its just a mystery,”said the United States Poet Laureate Ada Limón when asked how a poem gets its start.Limón is the 24th Poet Laureate of the US.She is the first Latina ever to receive th...“Often,its just a mystery,”said the United States Poet Laureate Ada Limón when asked how a poem gets its start.Limón is the 24th Poet Laureate of the US.She is the first Latina ever to receive the honor.The purpose of the role is to heighten appreciation of the art of poetry.It is the highest recognition for a poet in the US.展开更多
The influence of a 40-fold attenuated geomagnetic field and its combined action with low doses of α- and γ-irradiation on the physiological characteristics of seeds of the highest plants and redox properties of wate...The influence of a 40-fold attenuated geomagnetic field and its combined action with low doses of α- and γ-irradiation on the physiological characteristics of seeds of the highest plants and redox properties of water was investigated. It established the reduction of seed germination both under direct and indirect effects due to water action of attenuated geomagnetic field. A negative effect of hypomagnetic field on grown characteristics of seeds under indirect effect via water was decreased by the low doses of γ-irradiation, and was increased by low doses of α-irradiation, i.e. ionized radiation was the dominant factor in their combined action. It was revealed the increasing of the value of the oxidation-reduction potential of water under the influence of low-intensive α-ir-radiation (239Pu), γ-irradiation (137Cs) and also that the magnetic induction attenuated pointing to a natural decline. The increasing of the oxidation-reduction potential value testifies about “the regular decreasing of internal energy of water molecules” and the increasing of its oxidative properties, which, in our opinion, is caused the inhibition of the germination of seeds. It is supposed that namely water is the main component in the effects of studying factors on bio-objects, which acts due to the alterations of the properties and structural content of water.展开更多
Following the basin wide heavy flood on Changjiang River in 1998, a significant flood occurred in 1999. Comparative analysis of both floods in terms of flows and flooding situations shows that both floods had one comm...Following the basin wide heavy flood on Changjiang River in 1998, a significant flood occurred in 1999. Comparative analysis of both floods in terms of flows and flooding situations shows that both floods had one common feature, that is, the flood stages were fairly high. But they differed greatly at the same time, that is, the 1998 flood was a basin wide heavy one while the 1999 flood was a significant local one. At Yichang station there occurred eight flood peaks in 1998, while in 1999 only three peaks took place. The maximum peak discharge at this station in 1999 was 57 600 cubic meters per second, which was smaller than that in 1998. The maximum flood-volume in 30 d of the 1998 flood at this station equaled that in 1954, when an extraordinary heavy flood happened on the River, while the maximum flood-volume in 30 d in 1999 was 25.8 billion cubic meters per second smaller than the 1998 one. It is seen that inflow floods from the upstream Changjiang River (above Yichang) in 1999 were not so big. Comparison of flood volumes in longer period shows that the 1999 flood was relatively concentrated while the 1998 one had lasted longer duration. Analysis shows that flooding situations in both years differed significantly in terms of the flood volumes diverted from river channels due to dyke breaches and collapses, the cases of polder embankment collapses, the areas of inundated cultivated land and the numbers of dangerous events for hydraulic structures. These differences had been resulted from the different properties of both floods and the dyke strengthening efforts made after the 1998 flood. It is seen that flood control engineering constructions initiated in the days following the 1998 flood have played an important role in fighting the 1999 flood.展开更多
J. W. Hong shows in [1,2] that: in order to justify some geometric proposition, one needs only to justify a special instance. This work opens up a new field for mechanical theorem proving in elementary geometries. But...J. W. Hong shows in [1,2] that: in order to justify some geometric proposition, one needs only to justify a special instance. This work opens up a new field for mechanical theorem proving in elementary geometries. But it is quite difficult展开更多
基金supported by the National Key Technology R & D Program of the Ministry of Science and Technology of China (Grant No. 2006BAB14B01)the Innovation Program of Science and Technology of the Ministry of Water Resources of China (Grant No. XDS2007-04)
文摘The annual highest water level of Taihu Lake （Zm） is very significant for flood management in the Taihu Basin. This paper first describes the inter-annual and intra-annual traits of Zm from 1956 to 2000. Then, using the Mann-Kenall （MK） and Spearman （SP） nonparametric tests, the long-term change trends of area precipitation and pan evaporation in the Taihu Basin are determined. Meanwhile, using the Morlet wavelet transformation, the fluctuation patterns and change points of precipitation and pan evaporation are analyzed. Also, human activities in the Taihu Basin are described, including land use change and hydraulic project construction. Finally, the relationship between Zm, the water level of Taihu Lake 30 days prior to the day of Zm （Z0）, and the 30-day total precipitation and pan evaporation prior to the day of Zm （P and E0, respectively） is described based on multi-linear regression equations. The relative influence of climate change and human activities on the change of Zm is quantitatively ascertained. The results demonstrate that： （1） Zm was distinctly higher during the 1980-2000 period than during the 1956-1979 period, and the 30 days prior to the day of Zm are the key phase influencing Zm every year; （2） P increased significantly at a confidence level of 95% during the 1956-2000 period, while the reverse was true for E0; （3） The relationship between Zm, P and E0 distinctly changed after 1980; （4） Climate change and human activities together caused frequent occurrences of high Zm after 1980; （5） Climate change caused a substantially greater Zm difference between the 1956-1979 and 1980-2000 periods than human activities. Climate change, as represented by P and E0, was the dominant factor raising Zm, with a relative influence ratio of 83.6%, while human activities had a smaller influence ratio of 16.4%.
基金National Key Project for Basic Research, G19980408 CAS's Project (KZ951-A1-204, KZ95T-06) for Tibetan Research IGSNRR Project
文摘The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “greatest lake period” may be inferred by the last highest lake shorelines. They are several, even tens times larger than that at present. According to the analyses of tens of lakes on the Plateau, most dating data fell into the range of 40-25 ka BP, some lasted to 20 ka BP. It was corresponded to the stage 3 of marine isotope and interstitial of last glaciation. The occurrence of maximum areas of lakes marked the very humid period on the Plateau and was also related to the stronger summer monsoon during that period.
文摘The distribution of 0 and 1 is studied in the highest level a e-1of primitive sequences over Z/(2\+e). It is proved that the proportion of 0 (or 1) in one period of a e-1is between 40% and 60% for e≥8.
基金Supported in part by the Scientific Research Foundation of Zhejiang Provincial Education Department under grant number 20040322It is also sponsored by SRF for ROCS,SEM
文摘Let y be a generalized Kac-Moody algebra with an integral Borcherds-Cartan matrix. In this paper, we define a d-type weak quantum generalized Kac-Moody algebra wUq^d（y）, which is a weak Hopf algebra. We also study the highest weight module over the weak quantum algebra wUdq^d（y） and weak A-forms of wUq^d（y）.
基金Project for Enhancing International Impact of China STM Journals(2013–2015)the High Quality Scientific Journals Project(2014–2015Chinese Association for Science and Technology)
文摘CNKI has published the ＂Annual Report for International Citation of Chinese Academic Journals＂ since 2012. In the past three years, it has provided comprehensive data on the international impact of Chinese academic journals. Using the clout index （CI） to rank the Chinese academic journals, ＂the Highest International Impact Academic Journals of China＂ and ＂ the Excellent International Impact Academic Journals of China＂ are announced every year. By introducing the rating criteria of the ＂Annual Report for International Citation of Chinese Academic Journals＂, the characteristics of high impact journals are discussed. Especially, the status of the pharmaceutical journals is discussed. We found that there are increasing numbers of Chinese journals that are included in the SCI, and some of them are high impact journals. However, journals published in Chinese are still facing difficulties to be included in SCI, even though they show higher impact than journals published in other non-English languages. The Chinese Pharmaceutical journals need to enhance their international impact, but Journals on Chinese Medicine show high impact.
基金Supported by the Fundamental Research Funds for the Central Universities(Grant No.2232021G-13).
文摘In this paper,we prove that the electrical Lie algebra e D_(5)is isomorphic to the semidirect product of sp_(4)and a 2-step nilpotent Lie algebra.Furthermore,we classify the irreducible highest weight modules for e D_(5).
基金Project supported by the State Key Laboratory of Information Security,Graduate School of Chinese Academy of Sciences.
文摘The distribution of 0 and 1 is studied in the highest level ae-1, of primitive sequences over . / (2(?) ), and the upper and lower bounds on the ratio of the number of 0 to the number of 1 in one period of ae-1 are obtained. It is revealed that the larger e is, the closer to 1 the ratio will be.
文摘Decision-theoretic interval estimation requires the use of loss functions that, typically, take into account the size and the coverage of the sets. We here consider the class of monotone loss functions that, under quite general conditions, guarantee Bayesian optimality of highest posterior probability sets. We focus on three specific families of monotone losses, namely the linear, the exponential and the rational losses whose difference consists in the way the sizes of the sets are penalized. Within the standard yet important set-up of a normal model we propose: 1) an optimality analysis, to compare the solutions yielded by the alternative classes of losses;2) a regret analysis, to evaluate the additional loss of standard non-optimal intervals of fixed credibility. The article uses an application to a clinical trial as an illustrative example.
文摘Based on data from palynology, paleosols, paleolimnology, ice core, archeology, sea levels, etc. , we reconstructed climates and environments of the Holocene Megathermal maximum (7. 2-6. 0 ka B. P. ), particularly vegetation zones, temperatures, precipitation and sea-level fluctuations. Annual mean temperature during that period was estimated at 1 ℃ higher than today for South China, 2 ℃ higher for the Changjiang River Valley, about 3℃ higher for North China, Northeast China and Northwest China and up to 4 - 5 ℃ higher for southern Qinghai-Xizang Plateau. Relative winter temperatures increased much more than average annual temperatures. The centennial-scale warming was accompanied by the expansion of summer monsoon and recession of winter cold currents as well as northward and westward shift of vegetation zones. Higher lake levels registered in all inland lakes of Inner Mongolia, Xinjiang, Qinghai and Xizang indicated that precipitation increased to a certain extent. The Holocene highest sea level in East China about 1 -3 m higher than today, occurred within 6. 5 and 5. 0 kaB. P. and sea water covered coastal areas of about 7×104 km2, which was the Holocene greatest scope of transgression.
基金Supported by the National Natural Science Foundation of China（No.21390394） and the National Basic Research Program of China（Nos. 2012CB821700, 2011CB808703）.
文摘C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface area（345 m^2/g） and large mesopore size（ca. 4.2 nm）, capable of offering more accessible active sites as well as faster mass transfer for catalysis. Besides, the doping of C（2.21%, molar fraction） at the O sites in Nb2O5 lattice greatly enhanced visible-light response by lowering the band gap, thereby making the material a photocatalyst under visible-light irradiation. Typically, the C-doped Nb2O5 exhibited a high H2 evolution rate of ca. 39.10·μmol·g^-1·h^-1 and also degraded RhB dye completely after 30 min of visible light exposure, which turned out to be much better than Degussa P25 and pure Nb2O5 catalysts.
基金Project supported by the National Natural Science Foundation of China.
文摘Let F be an algebraically closed field and charF=0. In this note, using the method ofmixed product in ref. [1], the irreducible positive （negative） Z-graded module of Liesuperalgebra H（n） with base space V （top space V） is determined, where the highest weightof H（n）<sub>0</sub>-module V is not kλ<sub>1</sub> for any nonnegative integer k.
文摘In this paper, an interpolation polynomial operator F n(f; l,x) is constructed based on the zeros of a kind of Jacobi polynomials as the interpolation nodes. For any continuous function f(x)∈C b [-1,1] (0≤b≤l) F n(f; l,x) converges to f(x) uniformly, where l is an odd number.
文摘Using new combinatorics of Young walls,we give a new construction of the arbitrary level highest weight crystal B(λ)for the quantum affine algebras of types A^((2))_(2n),D^((2))_(n+1),A^((2))_(2n−1),D^((1))_(n),B^((1))_(n) and C^((1))_(n).We show that the crystal consisting of reduced Young walls is isomorphic to the crystal B(λ).Moreover,we provide a new realization of the crystal B(∞)in terms of reduced virtual Young walls and reduced extended Young walls.
基金Fundamental Research Funds for the Central Universities,China(No.2232021G13)。
文摘The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vectors of the Verma modules.The simple highest weight module is isomorphic to either that for the symplectic Lie algebra sp4 or Verma module.
文摘“Often,its just a mystery,”said the United States Poet Laureate Ada Limón when asked how a poem gets its start.Limón is the 24th Poet Laureate of the US.She is the first Latina ever to receive the honor.The purpose of the role is to heighten appreciation of the art of poetry.It is the highest recognition for a poet in the US.
文摘The influence of a 40-fold attenuated geomagnetic field and its combined action with low doses of α- and γ-irradiation on the physiological characteristics of seeds of the highest plants and redox properties of water was investigated. It established the reduction of seed germination both under direct and indirect effects due to water action of attenuated geomagnetic field. A negative effect of hypomagnetic field on grown characteristics of seeds under indirect effect via water was decreased by the low doses of γ-irradiation, and was increased by low doses of α-irradiation, i.e. ionized radiation was the dominant factor in their combined action. It was revealed the increasing of the value of the oxidation-reduction potential of water under the influence of low-intensive α-ir-radiation (239Pu), γ-irradiation (137Cs) and also that the magnetic induction attenuated pointing to a natural decline. The increasing of the oxidation-reduction potential value testifies about “the regular decreasing of internal energy of water molecules” and the increasing of its oxidative properties, which, in our opinion, is caused the inhibition of the germination of seeds. It is supposed that namely water is the main component in the effects of studying factors on bio-objects, which acts due to the alterations of the properties and structural content of water.
文摘Following the basin wide heavy flood on Changjiang River in 1998, a significant flood occurred in 1999. Comparative analysis of both floods in terms of flows and flooding situations shows that both floods had one common feature, that is, the flood stages were fairly high. But they differed greatly at the same time, that is, the 1998 flood was a basin wide heavy one while the 1999 flood was a significant local one. At Yichang station there occurred eight flood peaks in 1998, while in 1999 only three peaks took place. The maximum peak discharge at this station in 1999 was 57 600 cubic meters per second, which was smaller than that in 1998. The maximum flood-volume in 30 d of the 1998 flood at this station equaled that in 1954, when an extraordinary heavy flood happened on the River, while the maximum flood-volume in 30 d in 1999 was 25.8 billion cubic meters per second smaller than the 1998 one. It is seen that inflow floods from the upstream Changjiang River (above Yichang) in 1999 were not so big. Comparison of flood volumes in longer period shows that the 1999 flood was relatively concentrated while the 1998 one had lasted longer duration. Analysis shows that flooding situations in both years differed significantly in terms of the flood volumes diverted from river channels due to dyke breaches and collapses, the cases of polder embankment collapses, the areas of inundated cultivated land and the numbers of dangerous events for hydraulic structures. These differences had been resulted from the different properties of both floods and the dyke strengthening efforts made after the 1998 flood. It is seen that flood control engineering constructions initiated in the days following the 1998 flood have played an important role in fighting the 1999 flood.
文摘J. W. Hong shows in [1,2] that: in order to justify some geometric proposition, one needs only to justify a special instance. This work opens up a new field for mechanical theorem proving in elementary geometries. But it is quite difficult
