There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i...There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children.展开更多
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ...Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter.展开更多
The fertilization process is the net result of a complex sequence of events that collectively result in the fusion of theopposite gametes. The male gamete undergoes continuous morphological and biochemical modificatio...The fertilization process is the net result of a complex sequence of events that collectively result in the fusion of theopposite gametes. The male gamete undergoes continuous morphological and biochemical modifications during spermdevelopment in the testis (spermatogenesis), maturation in the epididymis, and capacitation in the female reproductivetract. Only the capacitated spermatozoa are able to recognize and bind to the bioactive glycan residue(s) on the ovum'sextracellular coat, the zona pellucida (ZP). Sperm-zona binding in the mouse and several other species is believed totake place in two stages. First, capacitated (acrosome-intact) spermatozoa loosely and reversibly adhere to the zona-in-tact ovum. In the second stage tight irreversible binding occurs. Both types of bindings are attributed to the presence ofglycan- binding proteins (receptors) on the sperm plasma membrane and their complementary bioactive glycan units(ligands) on the surface of the ZP. The carbohydrate-mediated adhesion event initiates a signal transduction cascade re-sulting in the exocytosis of acrosomal contents. This step is believed to be prerequisite which allows the hyperactivatedacrosome-reacted spermatozoa to penetrate the ZP and fertilize the ovum. This review focuses on the role of carbohy-drate residues in sperm-ovum interaction, and triggering of the acrosome reaction. I have attempted to discuss extensiveprogress that has been made to enhance our understanding of the well programmed multiple molecular events necessaryfor successful fertilization. This review will identify these events, and discuss the functional significance of carbohy-drates in these events.展开更多
This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.Aft...This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.After surveying various types of astral scientific tables in ancient China and their layouts,this paper discusses the characteristics and adoption of“licheng”立成tables,a specific kind of pick-up table that seems to have come into use in the Sui period(581–618)and to have been widespread from the Tang period(618–907)onward.The emergence of licheng tables relates largely to the internal development of ancient Chinese astronomy,but they were also probably inspired by auspicial tables and foreign astronomical tables.By comparing tables recorded in the“Lü-li zhi”and the existing licheng tables,we find that most licheng were deleted during the compilation of“Lü-li zhi”to reduce the number of volumes.Moreover,this paper discusses several common solutions used to compress the size of tables in“Lü-li zhi.”The adoption of licheng tables into the ancient Chinese astral sciences and the reformatting of them in“Lü-li zhi”give us a different perspective for understanding the development of ancient Chinese astronomical tables and the compilation of the calendrical portion of official histories.展开更多
ZTE Corporation announced on July 7, 2010 that it is ranked third in the global optical networking （ON） industry, according to the latest research by industry analyst firm Ovum. ZTE posted the strongest gains for th...ZTE Corporation announced on July 7, 2010 that it is ranked third in the global optical networking （ON） industry, according to the latest research by industry analyst firm Ovum. ZTE posted the strongest gains for the first quarter of 2010 and a strong increase in overall revenues to rise from its previous position as the seventh-ranked vendor in Q1,2009.展开更多
Shannon entropy in time domain is a measure of signal or system uncertainty.When based on spectrum entropy,Shannon entropy can be taken as a measure of signal or system complexity. Therefore,wavelet analysis based on ...Shannon entropy in time domain is a measure of signal or system uncertainty.When based on spectrum entropy,Shannon entropy can be taken as a measure of signal or system complexity. Therefore,wavelet analysis based on wavelet entropy measure can signify the complexity of non-steady signal or system in both time and frequency domain.In this paper,in order to meet the requirements of post-analysis on abundant wavelet transform result data and the need of information mergence,the basic definition of wavelet entropy measure is proposed,corresponding algorithms of several wavelet entropies,such as wavelet average entropy,wavelet time-frequency entropy,wavelet distance entropy, etc.are put forward,and the physical meanings of these entropies are analyzed as well.The application principle of wavelet entropy measure in ElectroEncephaloGraphy (EEG) signal analysis,mechanical fault diagnosis,fault detection and classification in power system are analyzed.Finally,take the transmission line fault detection in power system for example,simulations in two different systems,a 10kV automatic blocking and continuous power transmission line and a 500kV Extra High Voltage (EHV) transmission line,are carried out,and the two methods,wavelet entropy and wavelet modulus maxima,are compared,the results show feasibility and application prospect of the six wavelet entro- pies.展开更多
Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furn...Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furnace rollers and the strips contact frequently, alloy elements on the roller surface will form hard protuberance. We call this protuberance ＂pick-up＂. In addition, with the increase of the amount of dust in the furnace atmosphere, the occurrence of furnace roller pick-up will also increase. Through chemical reaction and physical accumulation analysis combined with practical experience, the causes of pick-up in different furnace sections were analyzed. Methods of preventing furnace roller pick-up in the high strength steel sheet processing line were discussed and solutions to improving the strip surface quality in the continous annealing furnace were provided.展开更多
文摘There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children.
基金Supported by National Key Research and Development Program of China(Project No.2017YFD0700800)Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ16E050003)+1 种基金Natural Science Foundation of China(Grant No.51505429)Science Foundation of Zhejiang Sci-Tech University(Grant No.15022011-Y)
文摘Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter.
基金The work was supported in part by grants HD25869 and HD34041 from the National Institute of Child & Human Development
文摘The fertilization process is the net result of a complex sequence of events that collectively result in the fusion of theopposite gametes. The male gamete undergoes continuous morphological and biochemical modifications during spermdevelopment in the testis (spermatogenesis), maturation in the epididymis, and capacitation in the female reproductivetract. Only the capacitated spermatozoa are able to recognize and bind to the bioactive glycan residue(s) on the ovum'sextracellular coat, the zona pellucida (ZP). Sperm-zona binding in the mouse and several other species is believed totake place in two stages. First, capacitated (acrosome-intact) spermatozoa loosely and reversibly adhere to the zona-in-tact ovum. In the second stage tight irreversible binding occurs. Both types of bindings are attributed to the presence ofglycan- binding proteins (receptors) on the sperm plasma membrane and their complementary bioactive glycan units(ligands) on the surface of the ZP. The carbohydrate-mediated adhesion event initiates a signal transduction cascade re-sulting in the exocytosis of acrosomal contents. This step is believed to be prerequisite which allows the hyperactivatedacrosome-reacted spermatozoa to penetrate the ZP and fertilize the ovum. This review focuses on the role of carbohy-drate residues in sperm-ovum interaction, and triggering of the acrosome reaction. I have attempted to discuss extensiveprogress that has been made to enhance our understanding of the well programmed multiple molecular events necessaryfor successful fertilization. This review will identify these events, and discuss the functional significance of carbohy-drates in these events.
文摘This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.After surveying various types of astral scientific tables in ancient China and their layouts,this paper discusses the characteristics and adoption of“licheng”立成tables,a specific kind of pick-up table that seems to have come into use in the Sui period(581–618)and to have been widespread from the Tang period(618–907)onward.The emergence of licheng tables relates largely to the internal development of ancient Chinese astronomy,but they were also probably inspired by auspicial tables and foreign astronomical tables.By comparing tables recorded in the“Lü-li zhi”and the existing licheng tables,we find that most licheng were deleted during the compilation of“Lü-li zhi”to reduce the number of volumes.Moreover,this paper discusses several common solutions used to compress the size of tables in“Lü-li zhi.”The adoption of licheng tables into the ancient Chinese astral sciences and the reformatting of them in“Lü-li zhi”give us a different perspective for understanding the development of ancient Chinese astronomical tables and the compilation of the calendrical portion of official histories.
文摘ZTE Corporation announced on July 7, 2010 that it is ranked third in the global optical networking （ON） industry, according to the latest research by industry analyst firm Ovum. ZTE posted the strongest gains for the first quarter of 2010 and a strong increase in overall revenues to rise from its previous position as the seventh-ranked vendor in Q1,2009.
基金Supported by the National Natural Science Foundation of China (No.50407009)Distinguished Scholars Foundation of Sichuan Province (No.06ZQ026-012)Science Fund of Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control,Ministry of Education,China (No.KW02002).
文摘Shannon entropy in time domain is a measure of signal or system uncertainty.When based on spectrum entropy,Shannon entropy can be taken as a measure of signal or system complexity. Therefore,wavelet analysis based on wavelet entropy measure can signify the complexity of non-steady signal or system in both time and frequency domain.In this paper,in order to meet the requirements of post-analysis on abundant wavelet transform result data and the need of information mergence,the basic definition of wavelet entropy measure is proposed,corresponding algorithms of several wavelet entropies,such as wavelet average entropy,wavelet time-frequency entropy,wavelet distance entropy, etc.are put forward,and the physical meanings of these entropies are analyzed as well.The application principle of wavelet entropy measure in ElectroEncephaloGraphy (EEG) signal analysis,mechanical fault diagnosis,fault detection and classification in power system are analyzed.Finally,take the transmission line fault detection in power system for example,simulations in two different systems,a 10kV automatic blocking and continuous power transmission line and a 500kV Extra High Voltage (EHV) transmission line,are carried out,and the two methods,wavelet entropy and wavelet modulus maxima,are compared,the results show feasibility and application prospect of the six wavelet entro- pies.
文摘Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furnace rollers and the strips contact frequently, alloy elements on the roller surface will form hard protuberance. We call this protuberance ＂pick-up＂. In addition, with the increase of the amount of dust in the furnace atmosphere, the occurrence of furnace roller pick-up will also increase. Through chemical reaction and physical accumulation analysis combined with practical experience, the causes of pick-up in different furnace sections were analyzed. Methods of preventing furnace roller pick-up in the high strength steel sheet processing line were discussed and solutions to improving the strip surface quality in the continous annealing furnace were provided.
