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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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Arterial Hypertension-Related Factors within Custodial Settings of Southern Benin in 2023
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作者 Mongbo Virginie Kpozehouen Alphonse Achille Kpétékousso 《Open Journal of Epidemiology》 2024年第1期157-166,共10页
Introduction: Hypertension, a non-communicable disease, is a major public health threat worldwide, accounting for a high level of morbidity and mortality. Although it has been extensively published among the general p... Introduction: Hypertension, a non-communicable disease, is a major public health threat worldwide, accounting for a high level of morbidity and mortality. Although it has been extensively published among the general population, further research is needed to understand the reality of hypertension within the custodial setting. This study aimed to investigate the factors associated with arterial hypertension in custodial settings in southern Benin in 2023. Methods: This was a cross-sectional, descriptive, analytical study held in prisons in southern Benin from March to April 2023, involving inmates selected by two-stage random sampling. In the first stage, four prisons out of the six in the southern region of Benin were selected by simple random sampling. In the second stage, the prisoners were selected by systematic random sampling, with the sampling frame being the numbered list of eligible prisoners in each prison selected. Data collected by observation and questionnaire survey were analyzed using Stata 11 software. Hypertension was defined as systolic blood pressure ≥ 140 mmHg and diastolic blood pressure ≥ 90 mmHg. Overweight was defined by a body mass index (weight/height<sup>2</sup> (kg/m<sup>2</sup>) ≥ 25. Factors associated with hypertension were identified by multiple logistic regression, at a 5% threshold of significance. Results: Altogether 336 inmates aged 37.55 ± 1.72 years were surveyed. The prevalence of hypertension in custodial settings in southern Benin in 2023 was 31.32% (95% CI [17.06;52.57]). Associated factors were inmate age (ORa = 3.36 95% CI: [1.94;5.85]) and abnormal waist circumference (ORa = 2.61 95% CI [1.27;5.40]). Conclusion: The prevalence of arterial hypertension in prisons of southern Benin (31.32%) is high when compared with the national average (25.9% (22.5-29.3)). The ministries of the Interior and Health need to collaborate to involve inmates in preventive strategies for non-communicable diseases, including hypertension. 展开更多
关键词 Arterial Hypertension Associated Factors INMATES Custodial setting BENIN
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Prospective randomized study to evaluate and compare the post-procedural sexual function in patients undergoing semi-rigid ureterorenoscopy for distal ureteric stones in three different operating room settings
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作者 Gajanan S.Bhat Anuradha Shastry 《Asian Journal of Urology》 CSCD 2024年第2期331-338,共8页
Objective:To evaluate and compare the effect of semi-rigid ureterorenoscopy on post-procedural sexual function with three different operating room settings.Methods:In this prospective randomized study,consecutive sexu... Objective:To evaluate and compare the effect of semi-rigid ureterorenoscopy on post-procedural sexual function with three different operating room settings.Methods:In this prospective randomized study,consecutive sexually active patients with normal pre-operative sexual function undergoing uncomplicated semi-rigid ureterorenoscopy for distal ureteric stones were randomized into three groups,with three different operating room settings.Procedure-related anxiety and sexual function were assessed pre-operatively using Amsterdam Preoperative Anxiety and Information Scale and Brief Sexual Function Inventory(in males)and Female Sexual Function Index-6(in females),respectively.All the participants were stented following the procedure,and the stent was removed after 3 weeks.Post-procedural sexual function and general discomfort were assessed and compared between three groups at 1 week,3 weeks,and 12 weeks.The effect of surgery-related anxiety,preoperative sexual function,age,and general discomfort(including stent-related discomfort)on post-procedural sexual function were analyzed using multiple regression analysis.A p-value of less than 0.05 was considered statistically significant.Results:Totally,327 eligible patients were randomized into three groups.The group of patients who underwent the procedural with a screen separating the operating area from the patient vision,while the patient could watch the endoscopy through a separate monitor,had better post-procedural sexual function compared to those who had total vision of the operating area as well as to those whose eyes were blocked.This difference was statistically significant.This post-procedural reduction in sexual function could not be attributed to in situ stent alone.Conclusions:Our study showed that semi-rigid ureterorenoscopy can have significant negative effect on sexual function,which can be reduced with proper preoperative counseling and an ideal operating room settings. 展开更多
关键词 Semi-rigid ureterorenoscopy Post-procedural sexual dysfunction Preoperative counselling Operating room setting
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Watson-Jones Anatomical Approach for Open Reduction and Internal Fixation of Proximal Femoral Fractures without Image Intensifier in a Low-Resource Setting
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作者 Loïc Fonkoue Gaspary Fodjeu +6 位作者 Kennedy Olivier Muluem Olivier Ngongang Theophile Nana Marie Ange Ngo Yamben DésiréAkaba Urich Tambekou Daniel Eone Handy 《Open Journal of Orthopedics》 2024年第4期173-186,共14页
Introduction: Standard procedures for surgical fixation of proximal femoral fractures (PFF) require an image intensifier which in developing countries remains a luxury. We hypothesized that, with a well-codified techn... Introduction: Standard procedures for surgical fixation of proximal femoral fractures (PFF) require an image intensifier which in developing countries remains a luxury. We hypothesized that, with a well-codified technique, the Watson Jones approach (WJA) without image intensifier nor traction table, can allow open reduction and internal fixation (ORIF) of PFF using Dynamic hip screw (DHS), with satisfactory outcome. Patients and methods: Forty one consecutive patients (mean age 59.5 ± 21.6 years, 61% males) who were followed in a Teaching Hospital for PFF treated by ORIF using the WJA and DHS from January 2016 to December 2020 were reassessed. The outcome measures were the quality of the reduction, the positioning of the implants, the tip-apex distance (TAD), the rate and delay of consolidation, the functional results using Postel Merle d’Aubigné (PMA) score, the rate of surgical site infection (SSI) and the overall mortality. Logistic regression was used to determine factors associated with mechanical failure. Results: The mean follow-up period was 33.8 ± 15.0 months. Fracture reduction was good in 31 (75.6%) cases and acceptable in 8(19.5%) cases. Implant position was fair to good in 37 (90.2%) patients. The mean TAD was 26.1 ± 3.9 mm. Three patients developed SSI. Consolidation was achieved in 38 (92.6%) patients. The functional results were good to excellent in 80.5% of patients. The overall mortality rate was 7.3%. There were an association between mechanical failure and osteoporosis (p = 0.04), fracture reduction (p = 0.003), and TAD (p = 0.025). In multivariate logistic regression, no independent factors were predictive of mechanical failure. Conclusion: This study shows that ORIF using DHS for PFF via the Watson-Jones approach without an image intensifier can give satisfactory anatomical and functional outcomes in low-resource settings. It provides and validates a reliable and reproducible technique that deserves to be diffused to surgeons in austere areas over the world. 展开更多
关键词 Proximal Femoral Fracture Watson-Jones Approach Dynamic Hip Screw Low Resource setting
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Age and geochemical evolution of granite magmatism in Olkhon region from Caledonian syncollisional ore-free granite to the rare metal granite and pegmatite of Middle Paleozoic intraplate setting
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作者 Viktor Antipin Valentina Makrygina +1 位作者 Larisa Kushch Nataliya Sheptyakova 《China Geology》 CAS CSCD 2024年第1期63-79,共17页
The detailed description of two granite complexes in the Olkhon subterrane is given.The Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon series.It includes migmatites,granite-gnei... The detailed description of two granite complexes in the Olkhon subterrane is given.The Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon series.It includes migmatites,granite-gneisses,granites and pegmatites of normal alkalinity;they belong to the type of syncollisional granites.The Middle Paleozoic Aya granite complex includes mother Aya massif of amazonite-bearing granites and several types of rare-metal pegmatites.They have elevated alkalinity,low of Ba,Sr,and high LILE and HFSE elements contents.The Aya pegmatites lie in northwest cracks of stretching and associated with the rise of the territory under the influence of the North Asian plume.These cracks and pegmatites mark the beginning of a new intraplate geodynamic setting.Two geochemical types are distinguished among the pegmatites of this complex.These are amazonite pegmatites of Li-F type with Ta mineralization and complex type pegmatite with Be-Rb-Nb-Ta and Li-F mineralization(the Ilixin vein).The Tashkiney pegmatite vein is similar to Ilixin,but lies in the gneisses of the Olkhon series.It shows high concentrations of Be,Nb,Ta,as well as W,Sn,but lacks Li and F,due to a greater depth and higher temperature of the melt crystallization of this pegmatite. 展开更多
关键词 PEGMATITE Geochemistry Submantle plume MAGMATISM Caledonian collision Middle Paleozoic intraplate setting Be-Rb-Nb-Ta-Li-F mineralization Olkhon region Russia
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Study on the Influence of Setting Parameters of Tunnel Centralized Smoke Extraction System on Fire Smoke Flow and Temperature Decay
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作者 Zhisheng Xu SohailMahmood Zihan Yu 《Frontiers in Heat and Mass Transfer》 EI 2024年第3期791-816,共26页
The centralized smoke exhaust system of shield tunnel is an important determinant for tunnel fire safety,and the use of different design parameters of the tunnel smoke exhaust system will affect the smoke exhaust effe... The centralized smoke exhaust system of shield tunnel is an important determinant for tunnel fire safety,and the use of different design parameters of the tunnel smoke exhaust system will affect the smoke exhaust effect in the tunnel,and the influence of different design parameters on the smoke exhaust effect and temperature attenuation of the tunnel can help engineers in designing a more effective centralized smoke exhaust system for the tunnel.In this paper,the Fire Dynamic Simulator(FDS)is utilized to examine smoke exhaust vent settings for a centralized exhaust system in shield tunnel with both flat and sloped conditions,including slopes of+4.5%and−4.5%,under a 30MWfire power with a 150m^(3)/s smoke exhaust rate.The results suggest that maintaining a vent spacing of 60m and a vent size of 4.0 m×1.5 m is a reasonable configuration for centralized smoke exhaust systems in both flat and slope shield tunnels.This choice helpsminimize construction costs and prevent excessive smoke accumulation.It also promotes favorable conditions for maintaining temperature distribution at 2-m height,visibility,smoke spread distance,and temperature below the ceiling,all below the threshold values,while ensuring high smoke extraction efficiency.However,in the slope section,the chimney effect can disrupt exhaust efficiency,visibility,ceiling temperature,and temperature distribution at a height of 2 m.Employing different opening methods,such as having 2 vents up and 4 vents down in a+4.5%slope and 4 vents up and 2 vents down in a−4.5%slope,can help mitigate these effects.Furthermore,the temperature decay formula for shield tunnels follows a bi-exponential decay pattern,and different design parameters of centralized smoke exhaust systems have minimal effects on temperature decay in shield tunnels. 展开更多
关键词 Smoke exhaust setting smoke spread efficiency temperature decay
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Significance of“Printing English”in the Curriculum Setting of Business English Majors(Publishing Direction)
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作者 LIN Xuecai 《Sino-US English Teaching》 2024年第4期177-181,共5页
With the development of the global economy and the quick growth of international exchanges,Business English major plays an increasingly important role in higher education.The training goal of Business English major(pu... With the development of the global economy and the quick growth of international exchanges,Business English major plays an increasingly important role in higher education.The training goal of Business English major(publishing direction)has gradually shifted from the improvement of studentslanguage abilities to the cultivation of more specialized business knowledge and publishing skills.As an important course for Business English majors(publishing direction),Printing English is of great significance for cultivating studentsprofessional quality,professional competitiveness,career development,and practical ability.From the perspective of curriculum setting,it is necessary to re-understand the importance of Printing English in the curriculum setting of Business English major(publishing direction),and put forward corresponding teaching methods and strategies. 展开更多
关键词 Business English major Printing English curriculum setting teaching strategies
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Phase-Based Optical Flow Method with Optimized Parameter Settings for Enhancing Displacement Measurement Adaptability
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作者 Zhaoxin Peng Menglian Liu +2 位作者 Zhiliang Wang Wei Liu Xian Wang 《Open Journal of Applied Sciences》 2024年第5期1165-1184,共20页
To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizi... To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizing parameter settings is proposed. The optimized parameters include the best measurement points of the Region of Interest (ROI) and the levels of pyramid filters. Additionally, to address the issue of updating reference frames in practical applications due to the difficulty in estimating the maximum effective measurement value, a mechanism for dynamically updating reference frames is introduced. Experimental results demonstrate that compared to representative image gradient-based displacement measurement methods, the proposed method exhibits higher measurement accuracy in engineering applications. This provides reliable data support for structural damage identification research based on vibration signals and is expected to broaden the engineering application prospects for structural health monitoring. 展开更多
关键词 Displacement Measurement Phase-Based Optical Flow Optimized Parameter setting
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Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays
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作者 Mostafa I. Saleh Gaber El-Saady +1 位作者 Ali M. Yousef El-Noby A. Ibrahim 《Journal of Power and Energy Engineering》 2024年第9期37-49,共13页
Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this... Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains. 展开更多
关键词 Directional Overcurrent Relay Protection Coordination Distributed Generators Central Protection Unite Multiple setting Group Protection Relay
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Effects of Microbial Fertilizer and Compound Feritlizer Mixed Application on Yield and Fruit Quality and Flowering and Fruit Setting of Following Year of Apple 被引量:2
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作者 杨素苗 杜纪壮 +4 位作者 徐国良 石海强 尼群周 俎文芳 秦立者 《Agricultural Science & Technology》 CAS 2016年第3期642-644,共3页
In order to study the application effect of microbial fertilizer and compound fertilizer mixed application on microirrigation apple, three types of fertilizers were applied in spring which were urea(CK, 15 kg/plant)... In order to study the application effect of microbial fertilizer and compound fertilizer mixed application on microirrigation apple, three types of fertilizers were applied in spring which were urea(CK, 15 kg/plant), microbial fertilizer(5.0 kg/plant),microbial fertilizer and compound fertilizer mixed(each 2.5 kg/plant) to study the effect of different fertilizer treatments on yield, fruit quality, flowering and fruit setting of Xinshijie apple. The results showed that application of microbial fertilizer could increase the yield, fruit weight and fruit shape index, significantly increase the flowering rates and inflorescence fruit setting rate of following year, while reduce the fruit hardness and soluble solids content, and the effect of microbial fertilizer and compound fertilizer mixed application on increasing fruit weight and yield was higher than that of microbial fertilizer separate application, the effect of the two was not obvious in other aspects. Therefore, microbial fertilizer could be used instead of some chemical fertilizer and organic fertilizer in apple production to reach the aim of increasing yield and efficiency, and the effect of microbial fertilizer and compound fertilizer mixed application was best. 展开更多
关键词 Microbial fertilizer APPLE YIELD Fruit quality Flowering and fruit setting
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Linguistic approaches to multiple attribute decision making in uncertain linguistic setting 被引量:2
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作者 徐泽水 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2004年第4期482-485,共4页
We studied multiple attribute decision-making problems with uncertain linguistic information, in which the preference values took the form of uncertain linguistic variables. We introduced some operational laws of unce... We studied multiple attribute decision-making problems with uncertain linguistic information, in which the preference values took the form of uncertain linguistic variables. We introduced some operational laws of uncertain linguistic variables and a formula for the comparison between two uncertain linguistic variables. We proposed two new aggregation operators called extended uncertain linguistic aggregation (EULA) operator and interval linguistic aggregation (ILA) operator, and then develop an EULA operator-based linguistic approach and an ILA operator-based linguistic approach, respectively, to multiple attribute decision making in uncertain linguistic setting. The approaches were straightforward and do not produce any loss of information. Finally, an illustrative example was given to verify the developed approaches and to demonstrate their practicality and effectiveness. 展开更多
关键词 AGGREGATES Fuzzy sets LINGUISTICS Mathematical operators
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Effect of Extreme Natural High Temperature on Seed Setting Rate of Rice(Oryza sativa L.) at Heading and Flowering Stage 被引量:1
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作者 朱镇 赵庆勇 +5 位作者 张亚东 陈涛 姚姝 周丽慧 于新 王才林 《Agricultural Science & Technology》 CAS 2015年第8期1666-1671,共6页
The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme na... The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme natural high temperature on seed setting rate of different rice cultivar (line). The results showed that the contin- uous high temperature showed certain effects on the seed setting rates of tested materials, and significant differences were shown in seed setting rate among differ- ent rice cultivars (lines). The seed setting rates differed significantly among indica F1 hybrids derived from different sterile and restorer lines, indicating that the sterile and restorer lines had great effects on heat tolerances of different F~ hybrids. The cor- relation analysis showed that the seed setting rates of conventional indica restorer lines and conventional japonica rice cultivars (lines) were negatively related to the daily highest temperature (P〉0.05), and the seed setting rates of indica F1 hybrids were positively related to the seed setting rates of their restorer lines. Total four in- dica restorer lines, including Ninghuiguangkangzhan, Shuhui 527, Chenghui 3203 and Xianyin-8, and four new japonica rice cultivars (lines), including Wuyinjinghui (B2), Nanjing 4//W3660/Nanjing 44 (B12) and Wuyun 2330/JD6011 (B22) were pre- liminarily screened, and their seed setting rates were all close to the normal level (90%). The screened rice cultivars (lines) showed higher heat tolerances. 展开更多
关键词 High temperature seed setting rate Heading and flowering stage RICE
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The Application of Maslow's Hierarchy of Needs to Educational Settings 被引量:3
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作者 孙景 陈杰 《海外英语》 2012年第5X期280-281,共2页
Hierarchy of Needs,one of the most influential motivation theories,was developed by Abraham Maslow in 1940-50's USA.Hi erarchy of Needs theory has great significance in understanding human motivation,management tr... Hierarchy of Needs,one of the most influential motivation theories,was developed by Abraham Maslow in 1940-50's USA.Hi erarchy of Needs theory has great significance in understanding human motivation,management training and personal development.The purpose of this paper is to investigate briefly the application of the theory to educational settings so as to guide a more effective education. 展开更多
关键词 MASLOW HIERARCHY of Needs EDUCATIONAL settingS
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Effect of Enhanced UV-B Radiation on Seed Setting Rate and 1 000-grain Weight of Indica Hybrid Rice Restorer Lines
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作者 况浩池 曾祥瑞 +5 位作者 罗俊涛 曾正明 杨扬 陈光珍 何兴材 付均 《Agricultural Science & Technology》 CAS 2013年第2期226-229,共4页
[Objective] This study was to investigate the effect of enhanced UV-B radiation on seed setting rate and 1 000-grain weight of hybrid rice combinations. [Method] The seed setting rate and 1 000-grain weight of 10 new ... [Objective] This study was to investigate the effect of enhanced UV-B radiation on seed setting rate and 1 000-grain weight of hybrid rice combinations. [Method] The seed setting rate and 1 000-grain weight of 10 new sterile indica restorer lines planted in pots under enhanced UV-B radiation and fluorescent lamps (control) were respectively measured, and the differences were compared. [Result] The enhanced UV-B radiation significantly reduced the seed setting rate of indica restorer lines, and the differences between that UV-B radiation treatment and control all reached extremely significant level. In addition, the enhanced UV-B radiation reduced the 1 000-grain weight of most indica restorer lines, and compared with that of control the difference achieved significant or very significant level. However, the effect of enhanced UV-B radiation on seed setting rate and 1 000-grain weight differed to different indica restorer lines, and the differences among restorer lines tested were significant or very significant, which indicated the possibility to screen antiUV-B radiation rice materials and combinations. Finally, the indica restorer lines 09R-14, Luhui 37 and 10R-7703 which were strongly resistant to UV-B radiation were screened out. [Conclusion] This study laid foundation for breeding hybrid rice varieties resistance to UV-B radiation. 展开更多
关键词 UV-B radiation Indica restorer lines Hybrid rice Seed setting rate Grain weight
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A Case Study of The Course Setting of Business English of South-Central University For Nationalities
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作者 吕昊 《海外英语》 2011年第10X期50-52,共3页
With the economic globalization and the demand of the situation, many higher universities set up business English major. However, since business English is still a new major and research field in higher education, lot... With the economic globalization and the demand of the situation, many higher universities set up business English major. However, since business English is still a new major and research field in higher education, lots of problems exist in the major construction, in which the issue of course settings is a heated one. The author believes that as for the course setting of business English that is an important branch of English for Specific Purposes (ESP), it should be based on the demand toward business English talents from the market and the characteristics of business English.This thesis will, based on the point view of student, further discuss the issue of business English. Based on the analysis, it is concluded that the course setting of business English in China is not mature enough, which has problems involved in the content and the time arrangement. The significance of this thesis is to put forward reasonable proposals in the hope of solving the problem in the course setting of business English so that the business English graduates will be fit for the needs of the society. 展开更多
关键词 ENGLISH for Specific Purposes (ESP) business ENGLISH COURSE settingS
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Metallogenesis related to Mesozoic Granitoids in the Nanling Range, South China and Their Geodynamic Settings 被引量:26
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作者 HUA Renmin CHEN Peirong ZHANG Wenlan YAO Junming LIN Jinfu ZHANG Zhanshi GU Shengyan LIU Xiaodong QI Huawen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第6期810-820,共11页
Affected by the compressive stress from the South-Central (Indo-China) Peninsula, the Indosinian orogenesis, characterized by collision, thrust and uplifting, took place inside the South China Plate during 250-230 M... Affected by the compressive stress from the South-Central (Indo-China) Peninsula, the Indosinian orogenesis, characterized by collision, thrust and uplifting, took place inside the South China Plate during 250-230 Ma. The ages of the Indosinian granitoids in the Nanling Range and vicinity areas are mostly 240-205 Ma, indicating that they were emplaced in both late collision and post-collision geodynamic environments. No important granite-related metallogenesis occurred in this duration. A post-orogenic setting started at the beginning of the Yanshanian Period, which controlled large-scale granitic magmatism and related metallogenesis. This paper makes the first attempt to divide the Yanshanian Period into three sub-periods, i.e. the early, middle and late Yanshanian Periods, based mainly on the features of magmatism, especially granitoids and related metallogenesis and their geodynamic environments. The magmatic association of the Early Yanshanian (about 185-170 Ma) comprises four categories of magmatism, i.e. basalt, bimodal volcanics, A-type granite and intraplate high-K calc-alkaline (HKCA) magmatism, which indicates an extension-thinning of lithosphere and upwelling of mantle material to a relative small and local extent. Pb-Zn, Cu and Au mineralizations associated with HKCA magmatism represents the first high tide of Mesozoic metallogenesis in the Nanling Range area. During the middle Yanshanian, the lithosphere was subjected to more extensive and intensive extending and thinning, and hence mantle upwelling and basaltic magma underplating caused a great amount of crust remelting granitoids. This period can be further divided into two stages. The first stage (170-150 Ma) is represented by large-scale emplacement of crust remelting granites with local tungsten mineralization at its end. The second stage (150-140 Ma) is the most important time of large-scale mineralizations of non-ferrous and rare metals, e.g. W, Sn, Nb-Ta, Bi, Mo, Be, in the Nanling Range area. The late Yanshanian (140-65 Ma) was generally characterized by full extension and breakup of the lithosphere of South China. However, owing to the influence of the Pacific Plate movement, the eastern part of South China was predominated by subduction-related compression, which resulted in magmatism of calc-alkaline and shoshonite series and related metallogeneses of Au, Ag, Pb-Zn, Cu and (Mo, Sn), followed by extension in its late stage. In the Nanling Range area, the late Yanshanian magmatism was represented by granitic volcanic-intrusive complexes and mafic dikes, which are genetically related to volcanic-type uranium and porphyry tin deposits, and the mobilization-mineralization of uranium from pre-existing Indosinian granites. 展开更多
关键词 METALLOGENESIS GRANITOIDS geodynamic setting Yanshanian Period Nanling Range
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SHRIMP Zircon U-Pb Dating of Alkaline Dykes in the Pobei Area,Beishan Rift,Xinjiang Autonomous Region,China:Implications for Tectonic Setting and Mantle Plume Events 被引量:11
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作者 MAO Jingwen Franco PIRAJNO +1 位作者 ZHANG Zuoheng WAN Yusheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期879-884,共6页
In the Beishan rift in the eastern Tianshan orogen, Xinjiang Province, a N-S-trending dyke swarm is present in the Pobei area. The swarm cuts through the 270-290 Ma mafic-ultramafic intrusions associated with Ni-Cu su... In the Beishan rift in the eastern Tianshan orogen, Xinjiang Province, a N-S-trending dyke swarm is present in the Pobei area. The swarm cuts through the 270-290 Ma mafic-ultramafic intrusions associated with Ni-Cu sulphide mineralization. These mafic-ultramafic intrusions are typically found along E-W major faults in the Tianshan orogenic belts. We report SHRIMP U-Pb dating of zircons from a dyke of alkaline composition, which yielded a mean age of 252~9 Ma. Alkaline dykes of the same age are found in the Altay region of Siberia. This age is younger than the 270-290 Ma intraplate magmatic events that produced the mafic-ultramafic intrusions in the region, but in general agreement with the 250-260 Ma Permian plume event that gave rise to the Siberian traps and the Emeishan flood basalts in SW China. We suggest that there is a link between the Emeishan event and the dyke swarm in the Beishan rift and that the intraplate magmatism at 270-290 Ma reflects an early stage of mantle plume activity. The N-S trending dyke swarm in the Beishan rift may represent a later stage in the evolution of mantle plume activity in the NW and SW of China. We also speculate that in Beishan rift and possibly elsewhere in the Tianshan region, the dykes fed basaltic volcanism, whose products have since been eroded due to the strong uplift of the Tianshan orogen as a result of the IndiaEurasia collision in the Cenozoic. 展开更多
关键词 Alkaline dykes SHRIMP tectonic setting mantle plume China
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Geochemistry of Carboniferous Sandstones (Sardar Formation), East-Central Iran: Implication for Provenance and Tectonic Setting 被引量:7
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作者 Mohammad KHANEHBAD Reza MOUSSAVI-HARAMI +2 位作者 Asadollah MAHBOUBI Mehdi NADJAFI Mohammad Hosein MAHMUDY GHARAIE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第5期1200-1210,共11页
Geochemical analysis of sandstones from the Sardar Formation (from two stratigraphic successions) in east-central Iran were used for identification of geochemical characterization of sandstones, provenance and tecto... Geochemical analysis of sandstones from the Sardar Formation (from two stratigraphic successions) in east-central Iran were used for identification of geochemical characterization of sandstones, provenance and tectonic setting. Sandstones in the two lithostratigraphic successions have similar chemical compositions suggesting a common provenance. Bulk-rock geochemistry analysis of Carboniferous sandstones from Sardar Formation indicates that they are mainly quartz dominated and are classified as quartzarenites, sublitharenites and subarkoses, derived from acid igneous to intermediate igneous rocks. Discrimination function analysis indicates that the sandstones of Sardar Formation were derived from quartzose sedimentary provenance in a recycled orogenic setting. Also, major and trace elements in sandstones of Sardar Formation (e.g., K2O/Na2O vs. SiO2 ) indicate deposition in a stable passive continental margin (PM). Chemical index of alteration (CIA) for these rocks (65%) suggests a moderate to relatively high degree of weathering in the source area. 展开更多
关键词 PROVENANCE CARBONIFEROUS tectonic setting GEOCHEMISTRY Sardar Formation Iran
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Generalized ordered weighted averaging operators based methods for MADM in intuitionistic fuzzy set setting 被引量:4
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作者 Wang Shuqi Li Dengfeng Wu Zhiqian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1247-1254,共8页
Multiattribute decision making(MADM) problems, in which the weights and ratings of alternatives are expressed with intuitionistic fuzzy(IF) sets, are investigated.Firstly, the relative degrees of membership and th... Multiattribute decision making(MADM) problems, in which the weights and ratings of alternatives are expressed with intuitionistic fuzzy(IF) sets, are investigated.Firstly, the relative degrees of membership and the relative degrees of non-membership are formulated as IF sets, the weights and values of alternatives on both qualitative and quantitative attributes may be expressed as IF sets in a unified way.Then a MADM method based on generalized ordered weighted averaging operators is proposed.The proposed method is illustrated with a numerical example. 展开更多
关键词 multiattribute decision making intuitionistic fuzzy set ordered weighted averaging operator fuzzy set.
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The Application of Goal-Setting Theory in the Second Classroom Teaching Activities of College English
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作者 宋琳琳 胡春华 《英语广场(学术研究)》 2012年第5期93-95,共3页
Interest is the precondition and motivation for people's accomplishment.However,due to the exam-oriented system,millions of parents and teachers neglect the interests of children,and our children nearly forget the... Interest is the precondition and motivation for people's accomplishment.However,due to the exam-oriented system,millions of parents and teachers neglect the interests of children,and our children nearly forget their interests or hobbies.Based on different interests of children,the thesis analyzes how to apply the goal-setting theory in the second classroom teaching activities of College English,using the example of Lushan College of Guangxi University of Technology. 展开更多
关键词 goal-setting theory second class teaching activities College English
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