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Federated Learning Model for Auto Insurance Rate Setting Based on Tweedie Distribution 被引量:1
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作者 Tao Yin Changgen Peng +2 位作者 Weijie Tan Dequan Xu Hanlin Tang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期827-843,共17页
In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining ... In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining the Tweedie regression model involves training on a centralized dataset,when the data is provided by multiple parties,training a privacy-preserving Tweedie regression model without exchanging raw data becomes a challenge.To address this issue,this study introduces a novel vertical federated learning-based Tweedie regression algorithm for multi-party auto insurance rate setting in data silos.The algorithm can keep sensitive data locally and uses privacy-preserving techniques to achieve intersection operations between the two parties holding the data.After determining which entities are shared,the participants train the model locally using the shared entity data to obtain the local generalized linear model intermediate parameters.The homomorphic encryption algorithms are introduced to interact with and update the model intermediate parameters to collaboratively complete the joint training of the car insurance rate-setting model.Performance tests on two publicly available datasets show that the proposed federated Tweedie regression algorithm can effectively generate Tweedie regression models that leverage the value of data fromboth partieswithout exchanging data.The assessment results of the scheme approach those of the Tweedie regressionmodel learned fromcentralized data,and outperformthe Tweedie regressionmodel learned independently by a single party. 展开更多
关键词 rate setting Tweedie distribution generalized linear models federated learning homomorphic encryption
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Studies on Seed Setting Stability in Associated with Temperature for a Two-Line Hybrid Rice,Liangyoupeijiu 被引量:7
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作者 LuChuan-gen ZONGShou-yu ZOUJiang-shi 《Rice science》 SCIE 2004年第4期191-194,共4页
When being planted in wide areas in southern China (23°23' - 33°23' N, 98°35' - 120°19' E, sea level above 2.7 - 1285 m), Liangyoupeijiu (LYPJ), a two-line hybrid rice combination, ... When being planted in wide areas in southern China (23°23' - 33°23' N, 98°35' - 120°19' E, sea level above 2.7 - 1285 m), Liangyoupeijiu (LYPJ), a two-line hybrid rice combination, showed a seed setting rate of 75.2 - 77.2%, which was lower by 4.3 - 7.5 percent point than that of an indica hybrid rice Shanyou 63 (CK), with similar values of grain yield and coefficients of variation to CK. Sowing during 5-25th of May in Nanjing (32°3' N, 118°48' E), China, LYPJ headed before 4th September, and gave a seed setting rate of 75 - 90%, and grain yield over 1 kg/m2. If the sowing date was delayed to 14 - 15th, June, its heading date would be as late as 17th - 21st September, and seed setting rate would be declined by 10 - 15% in comparison with that on a suitable sowing date. When flowering took place at an average daily temperature range of 13.7 - 28.5℃ for five days, the spikelet fertility (SF) would be increased by 1.9- 10.7%, for each increment of 1℃. The suitable (SF≥90%) and safe (SF≥75%) temperatures for flowering stage were indicated to be 26.5℃ and 22.9℃, respectively. To get a high and stable seed set in cultivating LYPJ, it was recommended that LYPJ would be planted in the areas south of 34癗, and the favorable average daily temperature during flowering stage should be at 26 - 28℃. 展开更多
关键词 RICE intersubspecific hybrid seed setting rate grain yield TEMPERATURE
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Increasing plant density increases Bt toxin concentration of boll wall in cotton by decreasing boll setting speed 被引量:1
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作者 ZHOU Mingyuan CHEN Chen +4 位作者 TAMBEL Leila I.M. CHEN Yuan ZHANG Xiang CHEN Yuan CHEN Dehua 《Journal of Cotton Research》 2021年第2期104-113,共10页
Background: In order to uncover the mechanism of significantly reduced insect resistance at the late developmental stage in cotton(Gossypium hirsutum L.),the relationship between boll setting rate under different plan... Background: In order to uncover the mechanism of significantly reduced insect resistance at the late developmental stage in cotton(Gossypium hirsutum L.),the relationship between boll setting rate under different planting densities and Bacillus thuringiensis(Bt)insecticidal concentrations in the boll wall were investigated in the present study.Two studies were arranged at Yangzhou,China during the 2017–2018 cotton growth seasons.Five planting densities(15000,25000,45000,60000 and 75000 plants per hectare)and the flower-removal treatment were imposed separately on Bt cotton cultivar Sikang3 to arrange different boll setting rates,and the boll setting rates and Bt toxin content were compared.Results: Higher boll setting rate together with lower Bt toxin contents in boll wall was observed under low planting density,whereas lower boll setting rate and higher Bt toxin contents were found under high planting density.Also,higher Bt protein concentration was associated with higher soluble protein content,glutamic-pyruvic transaminase(GPT),and glutamic oxaloacetate transaminase(GOT)activities,but lower amino acid content,and protease and peptidase activities.It was further confirmed that a higher boll setting rate with lower Bt protein content under flower-removal.Conclusions: This study demonstrated that the insecticidal efficacy of boll walls was significantly impacted by boll formation.Reduced protein synthesis and enhanced protein degradation were related to the reduced Bt toxin concentration. 展开更多
关键词 Bt cotton Boll setting rate Bt toxin Protein metabolism
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Factors Influencing the Outcrossed Seed-Setting Obstacles of Photo-thermo Sensitive Genie Male Sterile Rice
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作者 CHENXiong-hui WANBang-hui PENGHai-feng LUYan-peng LIAYGKe-qin ZHAOJing 《Rice science》 SCIE 2004年第3期113-119,共7页
Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the fact... Using photo-thermo sensitive genie male rice (PTGMS) Pei' ai 64S, W7415S, W6154S, N26S, Annong S, Nongken 58S, 7001S and 5088S as female parents and conventional indica lines 8258 and U89 as male parents, the factors affecting outcrossed seed-setting were analyzed. The PTGMS had obstacles in outcrossed seed setting influenced by inheritance and environment at varying degrees. Environmental temperature was regarded as the main factor that resulted in the outcrossed seed-setting obstacles. The sensitive stage was at the early stage of grain filling for outcrossed seed setting. There existed remarkable differences at the sensitivity stage, the duration of sensitive period, the sensitive level and the effective level of outcrossed seed-setting obstacles caused by environmental temperature among different PTGMS lines. Therefore, attention should be paid to outcrossed seed-setting obstacles in selection and utilization of PTGMS lines. 展开更多
关键词 RICE photo-thermo sensitive genie male sterile line outcrossing seed setting rate temperature sensitive stage co-relationship
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Abnormal Structure of Embryo Sac in Autotetraploid Rice 被引量:3
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作者 Guo Hai-bin FENG Jiu-huan Lu Yong-gen LIU Xiang-dong 《Rice science》 SCIE 2006年第4期257-264,共8页
The structures of mature embryo sacs in 13 genetic stock lines of autotetraploid rice (Oryza sativa L.), including indica, japonica and javanica, were studied by using the whole-mount stain-clearing laser scanning c... The structures of mature embryo sacs in 13 genetic stock lines of autotetraploid rice (Oryza sativa L.), including indica, japonica and javanica, were studied by using the whole-mount stain-clearing laser scanning confocal microscopy (WCLSM). Among the 13 autotetraploid rice, the majority of ovaries possess normal polygonum-type embryo sacs, while a few ovaries were characterized by abnormal embryo sacs. The abnormalities of embryo sacs could be classified into six categories, i. e. no female germ unit, abnormal polar nuclei, embryo sac degeneration, no egg apparatus, small embryo sac and 'double set' of embryo sacs. The frequency of abnormal embryo sac in japonica (26.6%) was higher than that in indica (19.34%). In addition, the major abnormalities in each autotetraploid line varied, suggesting that the abnormalities may be related to the genotypes of the varieties. 展开更多
关键词 autotetraploid rice STRUCTURE ANATOMY embryo sac seed setting rate
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Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice 被引量:3
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作者 CHEN Shi-qiang WANG Zhong LIU Man-xi XIE Zhao-wei WANG Hui-hui 《Rice science》 SCIE 2008年第2期125-130,共6页
The germination of pollen grain in vitro and the growth of pollen tube in the pistil of rice were observed with a microscope. The stigma was removed at different time points after pollination to study its effect on se... The germination of pollen grain in vitro and the growth of pollen tube in the pistil of rice were observed with a microscope. The stigma was removed at different time points after pollination to study its effect on seed setting rate. The rice pollen grain started to germinate at 2 min after pollination and the pollen tube penetrated stigma into style in 5-10 min, 30 min later the end of pollen tube reached the bottom of ovary, and only some pollen tubes arrived at embryo sac at 40 min after pollination. Meanwhile, a small amount of callose began to deposit in the pollen tubes, a great deal of callose was observed at 50 min after pollination, whereas the pollen grain began to shrink. The growing rates of pollen tube in the rice stigma, style and ovary were 1500, 5000, and 5400 μm/h, respectively. The seed setting rate was quite low when the stigma was removed at about 10-15 min after pollination, gradually increased when it removed at 20 min to 50 min after pollination, and over 60% when it removed at 50 min after pollination and finally tended to be stable. 展开更多
关键词 RICE pollen grain germination pollen tube growth seed setting rate microscopic observation
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Distribution of the Classification Traits in the F_2 Progeny of Two Crosses of indica/japonica in Rice (Oryza sativa)
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作者 ZHANOZai-jun LIANGCheng-ye ZHUYing-guo 《Rice science》 SCIE 2003年第1期23-28,共6页
Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F_2 progeny of indica-japonica hybrids, 02428/Pei'ai 64 and Taichung 65/Teqing. There existed resemblance no... Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F_2 progeny of indica-japonica hybrids, 02428/Pei'ai 64 and Taichung 65/Teqing. There existed resemblance normal distribution in plant height, and the distribution had no relationship with the seed setting rate and plant height in F_1 progeny, suggesting that there were no gametic selection for the plant height in the F_2 progeny of indica-japoniea hybrids. An average seed setting rate of the F_2 was equal to the F_1 populations in the recombination of 02428/Pei'ai 64 in which there was an excellent cross compatibility, but the remarkable increase in the seed setting rate from the F_1 to F_2 in Taichung 65/Teqing, indicating that gametic selection only took place in the indica-japonica crosses with low cross compatibility while null or little in the hybrids with high compatibility. There were many intermediate types among the leaf pubescence, color of hull at heading, and length of the first and second panicle internode, and these Cheng's morphological traits was distributed normally; there were also a little intermediate types in hull hairness and phenol reaction with bi-peak distribution; while length to width ratio of grain was inclined to the japonica types obviously showing a skewed distribution in the F2 population. Although Cheng's morphological traits in F_2 populations had inconsistent distribution types, Cheng's morphological traits index showed normal distribution, which suggested that intermediate types, i.e. indicalinous or japonicalinous, were primary in F_2 population. 展开更多
关键词 RICE indica-japonica crosses genetic effect generations DISTRIBUTION morphological traits seed setting rate plant height
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Studies on the Growth Habits and Characteristics of Two Polyploid Indica-Japonica Hybrid Rice with Powerful Heterosis
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作者 SONG Zhao-jian DU Chao-qun DAI Bing-cheng CHEN Dong-ling CHEN Jian-guo CAI De-tian 《Agricultural Sciences in China》 CAS CSCD 2007年第3期265-274,共10页
Based on a series of polyploid indica-japonica hybrid plant lines obtained from a new breeding strategy of using double predominance of wide cross and polyploidization to breed super flee, two polyploid indica-japonic... Based on a series of polyploid indica-japonica hybrid plant lines obtained from a new breeding strategy of using double predominance of wide cross and polyploidization to breed super flee, two polyploid indica-japonica hybrids, PSR073 and PSR120 were studied in their growth periods to show the powerful heterosis in a larger scale and to study the characteristics of polyploid indica-japonica hybrids more elaborately. The leaf age, tiller growth, flowering habits, and agronomic traits of them were observed to analyze their growth habits and characteristics. The results showed that the.agronomic traits of PSR073 and PSR120, such as the plant height, panicle length, grain length, grain width, and 1000-grain weight, all acquired obvious predominance of polyploidy, and that the seed setting rate was more than 83%. No significant difference was observed between the two tetraploids and common diploids in the leaf age, tiller growth, and flowering habits. It was concluded that the characteristics of the two powerful heterosis polyploid hybrids were different from those of the polyploid rice reported earlier. Wide cross and polyploidization had no negative effects on their growth habits and characteristics; on the contrary these had powerful heterosis. This had provided theoretic and practical evidences for their application to agricultural production. 展开更多
关键词 POLYPLOID indica-japonica hybrids growth habits and characteristics HETEROSIS seed setting rate
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Province-scale commonalities of some world-class gold deposits:Implications for mineral exploration 被引量:9
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作者 David I.Groves M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第3期389-399,共11页
Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical str... Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical structure of the exploration and mining industry makes this situation difficult to redress. Economic geologists can do little to influence the required changes to the overall structure and philosophy of an industry driven by business rather than geological principles, However, it should be possible to follow the lead of the oil industry and improve the success rate of greenfield exploration, necessary for the next group of lower-exploration-spend significant mineral deposit discoveries. Here we promote the concept that mineral explorers need to carefully consider the scale at which their exploration targets are viewed. It is necessary to carefully assess the potential of drill targets in terms of terrane to province to district scale, rather than deposit scale, where most current economic geology research and conceptual thinking is concentrated. If orogenic, IRGD, Carlin-style and IOCG gold-rich systems are viewed at the deposit scale, they appear quite different in terms of conventionally adop- ted research parameters. However, recent models for these deposit styles show increasingly similar source-region parameters when viewed at the lithosphere scale, suggesting common tectonic settings. It is only by assessing individual targets in their tectonic context that they can be more reliably ranked in terms of potential to provide a significant drill discovery. Targets adjacent to craton margins, other lithosphere boundaries, and suture zones are clearly favoured for all of these gold deposit styles, and such exploration could lead to incidental discovery of major deposits of other metals sited along the same tectonic boundaries. 展开更多
关键词 Mineral exploration Gold deposits Tectonic settings Mining industry Discovery rate
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