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A Review of the Research on the Influencing Factors of Enterprise Key Core Technology Breakthrough
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作者 Liangcan Liu Yuexian Zou 《Proceedings of Business and Economic Studies》 2024年第4期125-129,共5页
The breakthrough of key core technology is a theoretical and practical strategic issue to realize the rise of the country.This paper analyzes the concept of key core technology and its breakthrough and analyzes its ch... The breakthrough of key core technology is a theoretical and practical strategic issue to realize the rise of the country.This paper analyzes the concept of key core technology and its breakthrough and analyzes its characteristics.Based on the perspective of participants,this paper summarizes the influencing factors of key core technology breakthroughs in enterprises:internal and external enterprises,universities and scientific research institutions,and government.This paper expands the relevant research on key core technology breakthroughs and provides inspiration for enterprises to carry out key core technology research and breakthrough practices. 展开更多
关键词 key core technology breakthrough Concept discrimination Technical features Influencing factors
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Key Environmental Factors Monitoring System of Low-power Greenhouse Based on WSN Technology
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作者 柳军 陶建平 吕晓兰 《Agricultural Science & Technology》 CAS 2016年第2期449-452,共4页
A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs ... A low-power environmental monitoring system based on WSN technology is proposed to effectively monitor the environmental status and ensure the healthy growth of greenhouse crops in the greenhouse. The system performs dynamic mon- itoring on the environmental data of temperature, humidity, illumination, soil tempera- ture and humidity of the greenhouse, and it reduces the energy consumption by us- ing solar energy and lithium battery as the power supply mode and dynamic power management algorithm combined with improved routing protocol. Stable and reliable, the system could effectively monitor the key environmental factors in the green- house, making it of certain promotion value. 展开更多
关键词 Environmental monitoring GREENHOUSE Wireless sensor network WSN technology key factor
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Key factors in developing the trinitrobenzene sulfonic acid-induced post-inflammatory irritable bowel syndrome model in rats 被引量:12
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作者 Hong-Yan Qin Hai-Tao Xiao +3 位作者 Justin CY Wu Brian M Berman Joseph JY Sung Zhao-Xiang Bian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第20期2481-2492,共12页
AIM:To investigate the key factors in developing the trinitrobenzene sulfonic acid(TNBS)-induced postinflammatory irritable bowel syndrome(PI-IBS)model in rats. METHODS:TNBS was administered to rats at the following c... AIM:To investigate the key factors in developing the trinitrobenzene sulfonic acid(TNBS)-induced postinflammatory irritable bowel syndrome(PI-IBS)model in rats. METHODS:TNBS was administered to rats at the following conditions:(1)with different doses(20,10,5 mg/0.8 mL per rat);(2)with same dose in different concentrations(20 mg/rat,25,50 mg/mL);(3)in different ethanol percentage(25%,50%);and(4)at depth either 4 cm or 8 cm from anus.At 5 d and 4 wk after TNBS administration,inflammation severity and inflammation resolution were evaluated.At 4 and 8 wk after TNBS application,visceral hyperalgesia and enterochromaffin(EC)cell hyperplasia were assayed by abdominal withdrawal reflex test,silver staining and capillary electrophoresis. RESULTS:Our results showed that:(1)TNBS induced dose-dependent acute inflammation and inflammation resolution.At 5 d post TNBS,the pathological score and myeloperoxidase(MPO)activity in all TNBS treated rats were significantly elevated compared to that of the control(9.48±1.86,8.18±0.67,5.78± 0.77 vs 0,and 3.55±1.11,1.80±0.82,0.97±0.08 unit/mg vs 0.14±0.01 unit/mg,P<0.05).At 4 wk post TNBS,the pathological score in high and median dose TNBS-treated rats were still significantly higher than that of the control(1.52±0.38 and 0.80±0.35 vs 0,P<0.05);(2)Intracolonic TNBS administration position affected the persistence of visceral hyperalgesia.At 4 wk post TNBS,abdominal withdrawal reflex (AWR)threshold pressure in all TNBS-treated groups were decreased compared to that of the control(21.52 ±1.73 and 27.10±1.94 mmHg vs 34.44±1.89 mmHg,P<0.05).At 8 wk post TNBS,AWR threshold pressure in 8 cm administration group was still significantly decreased(23.33±1.33 mmHg vs 36.79±2.29 mmHg,P<0.05);(3)Ethanol percentage affected the TNBS-induced inflammation severity and visceral hyperalgesia.In TNBS-25%ethanol-treated group,the pathological score and MPO activity were significantly lowered compared to that of the TNBS-50%ethanoltreated group,while AWR threshold pressure were significantly elevated(36.33±0.61 mmHg vs 23.33±1.33 mmHg,P<0.05);and(4)TNBS(5 mg/0.8 mL per rat, in 50%ethanol,8 cm from anus)-treated rats recovered completely from the inflammation with acquired visceral hyperalgesia and EC cell hyperplasia at 4 wk after TNBS administration.CONCLUSION:TNBS dosage,concentration,intraco-lonic administration position,and ethanol percentage play important roles in developing visceral hyperalgesia and EC cell hyperplasia of TNBS-induced PI-IBS rats. 展开更多
关键词 Post-inflammatory Irritable bowel syndrome Rat model Trinitrobenzene sulfonic acid key factors
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Geological Characteristics and Ore-controlling Factors of the Beiya Gold–Polymetallic Ore Deposit, Northwestern Yunnan Province 被引量:9
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作者 ZHOU Yunman ZHANG Changqing +4 位作者 HE Zhonghua LIU Huan ZHOU Guiwu SUN Jia LIU Bo 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期1841-1861,共21页
Based on comprehensive petrological, geochronological, and geochemical studies, this study analyzed the relationships between the Beiya gold-polymetallic skarn deposit and quartz syenite porphyries, and discussed the ... Based on comprehensive petrological, geochronological, and geochemical studies, this study analyzed the relationships between the Beiya gold-polymetallic skarn deposit and quartz syenite porphyries, and discussed the source(s) and evolution of magmas. Our results suggest that syenite porphyries(i.e. the Wandongshan, the Dashadi, and the Hongnitang porphyries), which formed between the Eocene and the early Oligocene epochs, are the sources for the gold-polymetallic ores at the Beiya deposit. Carbonate rocks(T2 b) of the Triassic Beiya Formation in the ore district provide favorable host space for deposit formation. Fold and fault structures collectively play an important role in ore formation. The contact zone between the porphyries and carbonates, the structurally fractured zone of carbonate and clastic rocks, and the zone with well-developed fractures are the ideal locations for ore bodies. Four types of mineralization have been recognized: 1) porphyry-style stockwork gold–iron(copper) ore, 2) skarn-style gold-iron(copper and lead) ore in the near contact zone, 3) strata-bound, lense-type lead–silver–gold ore in the outer contact zone, and 4) distal vein-type gold–lead–silver ore. Supergene processes led to the formation of oxide ore, such as the weathered and accumulated gold–iron ore, the strata-bound fracture oxide ore, and the structure-controlled vein-type ore. Most of these ore deposits are distributed along the axis of the depressed basin, with the hypogene ore controlling the shape and characteristics of the oxide ore. This study provides critical geology understanding for mineral prospecting scenarios. 展开更多
关键词 porphyry-skarn type quartz syenite porphyries ore-controlling factors Beiya goldpolymetallic deposit northwestern Yunnan province
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Quantitative analysis of geological ore-controlling factors and stereoscopic quantitative prediction of concealed ore bodies 被引量:5
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作者 毛先成 邹艳红 +2 位作者 卢晓琴 吴湘滨 戴塔根 《Journal of Central South University》 SCIE EI CAS 2009年第6期987-993,共7页
To address the issues for assessing and prospecting the replaceable resource of crisis mines, a geological ore-controlling field model and a mineralization distribution field model were proposed from the viewpoint of ... To address the issues for assessing and prospecting the replaceable resource of crisis mines, a geological ore-controlling field model and a mineralization distribution field model were proposed from the viewpoint of field analysis. By dint of solving the field models through transferring the continuous models into the discrete ones, the relationship between the geological ore-controlling effect field and the mineralization distribution field was analyzed, and the quantitative and located parameters were extracted for describing the geological factors controlling mineralization enrichment. The method was applied to the 3-dimensional localization and quantitative prediction for concealed ore bodies in the depths and margins of the Daehang mine in Guangxi, China, and the 3-dimensional distribution models of mineralization indexes and ore-controlling factors such as magmatic rocks, strata, faults, lithology and folds were built. With the methods of statistical analysis and the non-linear programming, the quantitative index set of the geological ore-controlling factors was obtained. In addition, the stereoscopic located and quantitative prediction models were set up by exploring the relationship between the mineralization indexes and the geological ore-controlling factors. So far, some concealed ore bodies with the resource volume of a medium-sized mineral deposit are found in the deep parts of the Dachang Mine by means of the deep prospecting drills following the prediction results, from which the effectiveness of the predication models and results is proved. 展开更多
关键词 geological ore-controlling factor concealed ore body stereoscopic prediction
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Study of the key factors affecting the triple grid lifetime of the LIPS-300 ion thruster 被引量:4
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作者 孙明明 王亮 +3 位作者 杨俊泰 温晓东 黄永杰 王蒙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第4期152-163,共12页
In order to ascertain the key factors affecting the lifetime of the triple grids in the LIPS-300 ion thruster,the thermal deformation,upstream ion density and component lifetime of the grids are simulated with finite ... In order to ascertain the key factors affecting the lifetime of the triple grids in the LIPS-300 ion thruster,the thermal deformation,upstream ion density and component lifetime of the grids are simulated with finite element analysis,fluid simulation and charged-particle tracing simulation methods on the basis of a 1500 h short lifetime test.The key factor affecting the lifetime of the triple grids in the LIPS-300 ion thruster is obtained and analyzed through the test results.The results show that ion sputtering erosion of the grids in 5 kW operation mode is greater than in the case of 3 kW.In 5 kW mode,the decelerator grid shows the most serious corrosion,the accelerator grid shows moderate corrosion,and the screen grid shows the least amount of corrosion.With the serious corrosion of the grids in 5 kW operation mode,the intercept current of the acceleration and deceleration grids increases substantially.Meanwhile,the cold gap between the accelerator grid and the screen grid decreases from 1 mm to 0.7 mm,while the cold gap between the accelerator grid and the decelerator grid increases from 1 mm to 1.25 mm after 1500 h of thruster operation.At equilibrium temperature with 5 k W power,the finite element method(FEM)simulation results show that the hot gap between the screen grid and the accelerator grid reduces to 0.2 mm.Accordingly,the hot gap between the accelerator grid and the decelerator grid increases to 1.5 mm.According to the fluid method,the plasma density simulated in most regions of the discharge chamber is 1?×?10;-8?×?10;m;.The upstream plasma density of the screen grid is in the range 6?×?10;-6?×?10;m;and displays a parabolic characteristic.The charged particle tracing simulation method results show that the ion beam current without the thermal deformation of triple grids has optimal perveance status.The ion sputtering rates of the accelerator grid hole and the decelerator hole are 5.5?×?10;kg s;and 4.28?×?10;kg s;,respectively,while after the thermal deformation of the triple grids,the ion beam current has over-perveance status.The ion sputtering rates of the accelerator grid hole and the decelerator hole are 1.41?×?10;kg s;and 4.1?×?10;kg s;,respectively.The anode current is a key factor for the triple grid lifetime in situations where the structural strength of the grids does not change with temperature variation.The average sputtering rates of the accelerator grid and the decelerator grid,which were measured during the 1500 h lifetime test in5 k W operating conditions,are 2.2?×?10;kg s;and 7.3?×?10;kg s;,respectively.These results are in accordance with the simulation,and the error comes mainly from the calculation distribution of the upstream plasma density of the grids. 展开更多
关键词 the triple grids LIFETIME ion thruster key factor
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Optimization on Production Key Factors of Microbial Fermented Feed and Analysis on Composition Variation During Fermentation 被引量:4
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作者 Lin Biaosheng Luo Jian +3 位作者 Li Yiming He Yuqin Luo Maochun Yang Xiaoyan 《Animal Husbandry and Feed Science》 CAS 2017年第3期179-183,194,共6页
[ Objective] In order to study the production key factors of microbial fermented feed and the composition variation during fermentation. [ Methods ] Water, temperature, energy and protein were selected to study the ef... [ Objective] In order to study the production key factors of microbial fermented feed and the composition variation during fermentation. [ Methods ] Water, temperature, energy and protein were selected to study the effects on microbial fermented feed. And the fermentation conditions were optimized. Changes on nutrient composition during fermentation were determined and analyzed. [ Result ] Test results showed that feed formula with high sugar content, low protein, 34% - 36% water content, high fermentation temperature was more conducive to the production and actual production needs of fermentation strains. During the fermentation, strains showed interactions, test tended to be completed at the 144^th h after the fermentation, and number of lactic acid bacteria reached the peak of 1.86×10^9 strain/g, contents of lactic acid could even reach 0.89%. As time prolonged, contents of total energy, fiber and isothiocyanate gradually reduced, while contents of water and protein increased slightly. Contents of vitamin were stable, which in an order of VB〉 VE 〉 Vx 〉 VA 〉 VD. Composition of amino acids showed an better change, contents of glutamic acid and proline decreased slowly, while contents of glycine and phenylalanine increased slowly. [ Conclusion] High quality microbial fermentation feed could improve the palatability and safety of feed and keep the intestinal balance of livestock and poultry, which had broad application prospect. 展开更多
关键词 Microbes Fermented feed key factors Composition variation ANALYSIS
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Spatial distribution and potential poverty-returning factors of former poverty-stricken villages in the Liangshan Mountains,China
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作者 CHEN Yang SHU Bo +2 位作者 CHEN Yu HU Jin-hao WEI Dong 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2692-2707,共16页
Remote mountainous villages are at risk of falling back into poverty,despite having been lifted out of extreme poverty.However,there has been a lack of focus on the factors contributing to povertyreturn in these villa... Remote mountainous villages are at risk of falling back into poverty,despite having been lifted out of extreme poverty.However,there has been a lack of focus on the factors contributing to povertyreturn in these villages,which making it difficult to understand the risks and their underlying causes.This study investigates the spatial distribution of 546 key assistance villages(KAVs)in the Liangshan mountainous region,a former poverty-stricken area,using the average nearest neighbor(ANN)and kernel density estimation(KDE)methods.Linear regression and geographically weighted regression(GWR)models are then employed to analyze the relationship between the KAVs'economy and potential povertyreturning factors.The results show that KAVs are primarily located in elevation ranges of 1800-2500 m(31.87%),with slopes of 6°-15°(42.67%)and 2-3 km from the township(28.94%).The distribution of KAVs exhibits distinct spatial clustering,forming four gathering areas.Several factors impact the KAVs'economy positively,including the normalized difference vegetation index(NDVI),built-up area,grassland,and education facilities,while elevation has a negative effect.The built-up area has the most critical impact on the rural economy,followed by NDVI and elevation.Additionally,education facilities and grassland areas also have significant effects.The study suggests promoting the Ex-situ Poverty Alleviation Relocation Program(ESPARP)and increasing rural built-up areas,grasslands,and educational facilities as practical measures for preventing poverty return and promoting economic development promotion in remote mountain villages. 展开更多
关键词 key assistance villages Rural revitalization Spatial distribution Potential poverty-returning factors Geographically weighted regression
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Effect of key factors on cold orbital forging of a spur bevel gear 被引量:1
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作者 庄武豪 董丽颖 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期277-285,共9页
Cold orbital forging is an advanced spur bevel gear forming technology. Generally, the spur bevel gear in the cold orbital forging process is formed by two steps: the preforming step and the final step. Due to the gre... Cold orbital forging is an advanced spur bevel gear forming technology. Generally, the spur bevel gear in the cold orbital forging process is formed by two steps: the preforming step and the final step. Due to the great importance of the final step to gear forming and its complication with interactive factors, this work aims at examining the influence of key factors on the final step in cold orbital forging of a spur bevel gear. Using the finite element(FE) method and control variate method, the influence rules of four key factors, rotation velocity of the upper tool, n, feeding velocity of the lower tool, v, tilted angle of the upper tool, γ, friction factor between the tools and the billet, m, on the geometry and the deformation inhomogeneity of the cold orbital forged gear are thoroughly clarified. The research results show that the flash becomes more homogeneous with increasing v, increasing m, decreasing n or decreasing γ. And the deformation of the gear becomes more homogeneous with increasing v, decreasing n or decreasing γ. Finally, a corresponding experiment is conducted, which verifies the accuracy of FE simulation conclusions. 展开更多
关键词 cold orbital forging FE modeling key factors spur bevel gears
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Identifying Key Environmental Factors Influencing Spatial Variation of Water Quality in Upper Shitoukoumen Reservoir Basin in Jilin Province,China
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作者 TANG Yanling ZHANG Guangxin +1 位作者 YANG Yuesuo GAO Yingzhi 《Chinese Geographical Science》 SCIE CSCD 2009年第4期365-374,共10页
Based on the observed data in monitored drainage areas and GIS spatial analysis tools,watershed basic database of Shitoukoumen Reservoir Basin was built.The multivariate analysis and redundancy analysis(RDA) were used... Based on the observed data in monitored drainage areas and GIS spatial analysis tools,watershed basic database of Shitoukoumen Reservoir Basin was built.The multivariate analysis and redundancy analysis(RDA) were used to analyze the spatial and temporal variations of water quality,identify the key environmental factors and their patterns influencing the spatial variation of water quality,and determine the main types and forms of the non-point source(NPS) pollutant export controlled by the key environmental factors.The results show that different patterns of environmental factors lead to great changes in water quality at spatial and seasonal scales.All selected environmental factors explain 64.5% and 68.2% of the spatial variation of water quality over dry season and rainy season,respectively,which shows clear seasonal difference.Over dry season,residential land is the most important environmental factor,which possesses 35.4% of the spatial variation,and drainage area is the second key environmental factor,which possesses 17.0% of spatial variation in the total variance.Over rainy season,slope length and drainage area are the key environmental factors,which possess 29.3% of the spatial variation together.Residential land influences nitrogen export by changing NH4+-N and particulate organic nitrogen(PON) discharge over dry season,and drainage area controls phosphorus export by regulating dissolved phosphorus(DP) drainage over dry season and phosphorus associated particulate(PAP) loss over rainy season,respectively.Although slope length is an important environmental factor,it does not influence NPS pollutant export.It is interesting that soil organic matter,as a minor environmental factor,highly determines phosphorus and nitrogen export by enhancing the DP,PAP and PON loss. 展开更多
关键词 non-point source pollution key environmental factor redundancy analysis Shitoukoumen Reservoir
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Key Human Factors of Vehicle Interior Occupant Packaging in SAE Standard
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作者 丁祎 胡平 +1 位作者 靳春宁 吴晓军 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期38-44,共7页
Fourteen SAE standards related to accommodation and occupant' packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationship... Fourteen SAE standards related to accommodation and occupant' packaging for vehicle interior are studied. The influencing factors, key reference accommodation points and major design dimensions and their relationships of occupant packaging and ergonomics during the vehicle interior layout design and development are analyzed. Prototypes are presented to verify the results and how to achieve the packaging is shown. Auto- mobile designers can achieve significant practical guidance for human safety, efficiency accommodation and occupant packaging of all passengers during the vehicle design process. 展开更多
关键词 vehicle interior occupant packaging vehicle layout design and verification key design factors
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Study on the Key Influence Factors of Environmental Mass Incidents by Delphi-PCA-Frequency Analysis Composite Method
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作者 Chuai Xiaoming HAN Jingwen +1 位作者 Zhou Ying Wang Jiajia 《Meteorological and Environmental Research》 CAS 2018年第3期54-59,共6页
In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. A... In order to prevent and control environmental mass incidents,by comprehensively using literature research,case analysis and logical reasoning method,27 factors influencing environmental mass incidents were selected. Among them,15 key influencing factors were screened by Delphi-PCA-frequency analysis composite method. The key influencing factors were analyzed,and corresponding countermeasures were put forward. 展开更多
关键词 Environmental mass incidents Delphi-PCA-frequency analysis key influence factors
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ORE-CONTROLLING FACTORS AND PROSPECTS OF GEODEPRESSION (DIWA) BASIN SANDSTONE TYPE COPPER DEPOSITS IN CHINA
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《Geotectonica et Metallogenia》 1994年第Z2期48-49,共2页
关键词 ore-controlLING factors AND PROSPECTS OF GEODEPRESSION BASIN SANDSTONE TYPE COPPER DEPOSITS IN CHINA DIWA
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Impacts of Environmental Factors on the Structure Characteristics of Avian Community in Shanghai Woodlots in Spring 被引量:31
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作者 葛振鸣 王天厚 +2 位作者 施文彧 周立晨 薛文杰 《Zoological Research》 CAS CSCD 北大核心 2005年第1期17-24,共8页
From March to May, 2004, we selected 8 typical parks or green lands in Shanghai downtown as the study sites to conduct a ornithological research. During this study, total 55 species of birds were recorded, which inclu... From March to May, 2004, we selected 8 typical parks or green lands in Shanghai downtown as the study sites to conduct a ornithological research. During this study, total 55 species of birds were recorded, which included 31 resident and 24 migratory species. With statistics methodology, we analyzed the avian communities with 10 major environmental factors covering the park area, water percentage, vegetation species, canopy cover, shrub cover, grass cover, hill number, location condition, human quantity, path width, the study results indicated that: (1) the following 7 environmental factors were important to impact the structures of the avian community, they were park area, vegetation species, shrub coverage, grass coverage, hill number, location condition of the parks and path width; (2) the avian community of theses urban parks tended to deteriorate in the bird number and diversity; the man-made lake which was currently promoted in the park designing and planning process would not be good to attract the birds. 展开更多
关键词 Urban avian community Bird diversity key environmental factor Shanghai park
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Risk Factors of Cervical Carcinoma and Countermeasures against Them in Mountainous Area of Wufeng County, China 被引量:1
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作者 TAONing WUXu-feng +3 位作者 QIUXiao-ping ZHAOMin TANYun WUXin-xing 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期759-766,共8页
Cases (n=44) with squamous cell cervical cancer (SCCA) and age-matched healthy controls (n=176) were analyzed. Significant difference due to human papillomavirus (HPV) infection, ages at the first marriage, ages at th... Cases (n=44) with squamous cell cervical cancer (SCCA) and age-matched healthy controls (n=176) were analyzed. Significant difference due to human papillomavirus (HPV) infection, ages at the first marriage, ages at the first sexual intercourse, ages at the first birth given to baby, number of gravidities, number of deliveries, Body Mass Index (BMI), education level of women and their husbands (p<0.05) was observed. According to multivariate logistic regression analysis, four factors have entered the model (p<0.05), including HPV infection [OR (odds ratio)=26.13, 95%CI (confidence interval)=9.40?72.60], education level of women (OR=0.41, 95%CI=0.21?0.79), education level of spouses (OR=0.45, 95%CI=0.22?0.94), BMI (OR=0.73, 95%CI=0.57?0.93). Moreover, HPV infection is relative to education level of women (r=?0.14), and their spouses (r=?0.21), age at the first marriage (r=?0.20), age at the first birth given to baby (r=?0.20) and BMI (r=?0.15). 展开更多
关键词 key words cervical carcinoma human papillomavirus (HPV) risk factor
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R & D A Key Driving Factor of the Pipeline Industry
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《China Oil & Gas》 CAS 1999年第4期239-240,共2页
Kalamay-Dushanzioilpipelinebuiltin1958isthefirstlongdistanceoilpipelineofChina.Since1960s,withthedevelopmentofDaqing,Shengli,HuabeiandZhongyuanoilfields,oilpipelinenetworkscoveringnortheast,eastChina,andnorthChinahave... Kalamay-Dushanzioilpipelinebuiltin1958isthefirstlongdistanceoilpipelineofChina.Since1960s,withthedevelopmentofDaqing,Shengli,HuabeiandZhongyuanoilfields,oilpipelinenetworkscoveringnortheast,eastChina,andnorthChinahavebeensetup.Withthedevelopmentofnat... 展开更多
关键词 D A key Driving factor of the Pipeline Industry
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从社会幸福感到积极心理健康模型—Keyes介评 被引量:19
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作者 苗元江 赵姗 《心理研究》 2009年第5期13-16,25,共5页
继主观幸福感、心理幸福感后,Keyes提出了社会幸福感理论,构成幸福感理论第三阵营。其主要贡献涉及社会幸福感理论与测量、心理健康双因素理念,倡导积极心理健康模型,深化了幸福感的理解,拓展了幸福感的应用,架构了从幸福感到积极心理... 继主观幸福感、心理幸福感后,Keyes提出了社会幸福感理论,构成幸福感理论第三阵营。其主要贡献涉及社会幸福感理论与测量、心理健康双因素理念,倡导积极心理健康模型,深化了幸福感的理解,拓展了幸福感的应用,架构了从幸福感到积极心理健康的桥梁。 展开更多
关键词 keyes 社会幸福感 双因素理论 积极心理健康模型
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Future Drought Changes in China Projected by the CMIP6 Models:Contributions from Key Factors 被引量:2
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作者 Qingxin CHEN Tianbao ZHAO +3 位作者 Lijuan HUA Jinhua YU Yafang WANG Chuan XU 《Journal of Meteorological Research》 SCIE CSCD 2023年第4期454-468,共15页
Model simulations show that drought may become more severe and widespread in the 21st century due to humaninduced global warming. However, the contributions from the key factors to the model-projected drought changes ... Model simulations show that drought may become more severe and widespread in the 21st century due to humaninduced global warming. However, the contributions from the key factors to the model-projected drought changes in China have not yet been examined in detail. We used the self-calibrated Palmer Drought Severity Index with Penman–Monteith potential evapotranspiration(scPDSIpm) based on 10 model simulations selected from the Coupled Model Intercomparison Project Phase 6(CMIP6). We investigated the contributions from precipitation(P), near-surface air temperature and specific humidity [Δ(T + q)], net surface longwave radiation(LW), net surface shortwave radiation(SW), and wind speed(WS) to the future changes in scPDSIpm, including the long-term mean, drying area,probability distribution function(PDF), drought frequency, and drought duration based on the scPDSIpm over China.Our results show that model-projected drying mainly occurs over southern China, whereas the dry areas under drought conditions increase from 20% to about 23%/30% under the two scenarios of the shared socioeconomic pathway(SSP2-4.5/SSP5-8.5) from 1985 to 2100, despite large uncertainties in individual projections partly due to internal variability. Drought frequency is projected to increases by about 10%–54%(15%–88%) under the SSP2-4.5(SSP5-8.5) scenario by the late 21st century, along with increases in drought duration. These changes are accompanied by a decrease in the mean scPDSIpm and flattening of the PDFs. The changes in drying over southern China are mainly attributed to surface warming and the increased surface vapor pressure deficit(VPD), with small contributions from changes in the surface net radiation. The changes in wetting over northern China mostly result from increased precipitation along with a small wetting effect from the changes in wind speed. 展开更多
关键词 DROUGHT future projection key factors China Coupled Model Intercomparison Project Phase 6
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Anomalous Cell Detection with Kernel Density-Based Local Outlier Factor 被引量:2
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作者 Miao Dandan Qin Xiaowei Wang Weidong 《China Communications》 SCIE CSCD 2015年第9期64-75,共12页
Since data services are penetrating into our daily life rapidly, the mobile network becomes more complicated, and the amount of data transmission is more and more increasing. In this case, the traditional statistical ... Since data services are penetrating into our daily life rapidly, the mobile network becomes more complicated, and the amount of data transmission is more and more increasing. In this case, the traditional statistical methods for anomalous cell detection cannot adapt to the evolution of networks, and data mining becomes the mainstream. In this paper, we propose a novel kernel density-based local outlier factor(KLOF) to assign a degree of being an outlier to each object. Firstly, the notion of KLOF is introduced, which captures exactly the relative degree of isolation. Then, by analyzing its properties, including the tightness of upper and lower bounds, sensitivity of density perturbation, we find that KLOF is much greater than 1 for outliers. Lastly, KLOFis applied on a real-world dataset to detect anomalous cells with abnormal key performance indicators(KPIs) to verify its reliability. The experiment shows that KLOF can find outliers efficiently. It can be a guideline for the operators to perform faster and more efficient trouble shooting. 展开更多
关键词 data mining key performance indicators kernel density-based local outlier factor density perturbation anomalous cell detection
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New Weak Keys in RSA
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作者 WANG Baocang LIU Shuanggen HU Yupu 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1529-1532,共4页
The security of the RSA system with the prime pairs of some special form is investigated. A new special-purpose algorithm for factoring RSA numbers is proposed. The basic idea of the method is to factor RSA numbers by... The security of the RSA system with the prime pairs of some special form is investigated. A new special-purpose algorithm for factoring RSA numbers is proposed. The basic idea of the method is to factor RSA numbers by factoring a well-chosen quadratic polynomial with integral coefficients. When viewed as a general-purpose algorithm, the new algorithm has a high computational complexity. It is shown thai the RSA number n = pq can be easily factored if p and q have the special form of p = as+b, q=cs+d, where a, b, c, d are relatively small numbers. Such prime pairs (p, q) are the weak keys of RSA, so when we generate RSA modulus, we should avoid using such prime pairs (p, q). 展开更多
关键词 integer factorization RSA number public key cryptosystem special-purpose algorithm
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