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Maize kernel weight responses to sowing dateassociated variation in weather conditions 被引量:21
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作者 Baoyuan Zhou Yang Yue +3 位作者 Xuefang Sun Zaisong Ding Wei Ma Ming Zhao 《The Crop Journal》 SCIE CAS CSCD 2017年第1期43-51,共9页
Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions an... Variation in weather conditions during grain filling has substantial effects on maize kernel weight(KW). The objective of this work was to characterize variation in KW with sowing date-associated weather conditions and examine the relationship between KW, grain filling parameters, and weather factors. Maize was sown on eight sowing dates(SD) at 15–20-day intervals from mid-March to mid-July during 2012 and 2013 in the North China Plain. With sowing date delay, KW increased initially and later declined, and the greatest KW was obtained at SD6 in both years. The increased KW at SD6 was attributed mainly to kernel growth rate(Gmean), and effective grain-filling period(P). Variations in temperature and radiation were the primary factors that influenced KW and grain-filling parameters. When the effective cumulative temperature(AT) and radiation(Ra)during grain filling were 950 °C and 1005.4 MJ m-2, respectively, P and KW were greatest. High temperatures(daily maximum temperature [Tmax] > 30.2 °C) during grain filling under early sowing conditions, or low temperatures(daily minimum temperature [Tmin] < 20.7 °C) under late sowing conditions combined with high diurnal temperature range(Tmax-min> 7.1 °C) decreased kernel growth rate and ultimately final KW. When sowing was performed from May 25 through June 27, higher KW and yield of maize were obtained. We conclude that variations in environmental conditions(temperature and radiation) during grain filling markedly affect growth rate and duration of grain filling and eventually affect kernel weight and yield of maize. 展开更多
关键词 MAIZE Sowing date weather conditions Kernel weight Grain filling
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Innovation of the double-maize cropping system based on cultivar growing degree days for adapting to changing weather conditions in the North China Plain 被引量:3
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作者 WANG Dan LI Guo-rui +6 位作者 ZHOU Bao-yuan ZHAN Ming CAO Cou-gui MENG Qing-feng XIA Fei MA Wei ZHAO Ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第12期2997-3012,共16页
Double-maize cropping system is an effective option for coping with climate change in the North China Plain. However, the effects of changes in climate on the growth and yield of maize in the two seasons are poorly un... Double-maize cropping system is an effective option for coping with climate change in the North China Plain. However, the effects of changes in climate on the growth and yield of maize in the two seasons are poorly understood. Forty-six cultivars of maize with different requirements for growing degree days (GDD), categorized as high (H), medium (M) or low (L), and three cultivar combinations for two seasons as LH (using JD27 and DMY1 from category L in the first season;and YD629 and XD22 from category H in the second season), MM (using JX1 and LC3 from category M in the first season;and ZD958 and JX1 from category M in the second season) and HL (using CD30 and QY9 from category H in the first season;and XK10 and DMY3 from category L in the second season) were tested to examine the eco-physiological determinants of maize yield from 2015 to 2017. The correlations between the combinations of cultivars and grain yield were examined. The combination LH produced the highest annual grain yield and total biomass, regardless of the year. It was followed, in decreasing order, by MM and HL. Higher grain yield and biomass in LH were mainly due to the greater grain yield and biomass in the second season, which were influenced mainly by the lengths of the pre- and post-silking periods and the rate of plant growth (PGR). Temperature was the primary factor that influenced dry matter accumulation. In the first season, low temperatures during pre-silking decreased both the duration and PGR in LH, whereas high temperatures during post-silking decreased the PGR in MM and HL, resulting in no significant differences in biomass being observed among the three combinations. In the second season, high temperatures decreased both the PGR and pre- and post-silking duration in MM and HL, and consequently, the biomass of those two combinations were lower than that in LH. Moreover, because of lower GDD and radiation in the first season and higher grain yield in the second season, production efficiency of temperature and radiation (Ra) was the highest in LH. More importantly, differences in temperature and radiation in the two seasons significantly affected the rate and duration of growth in maize, and thereby affecting both dry matter and grain yield. Our study indicated that the combination of LH is the best for optimizing the double-maize system under changing climatic conditions in the North China Plain. 展开更多
关键词 double-maize cropping system weather conditions grain yield North China Plain
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The relationship between ischemic stroke and weather conditions in Duzce, Turkey 被引量:6
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作者 Harun Gunes Hayati Kandis +2 位作者 Ayhan Saritas Suber Dikici Ramazan Buyukkaya 《World Journal of Emergency Medicine》 CAS 2015年第3期207-211,共5页
BACKGROUND: Weather conditions are thought to increase the risk of stroke occurrence. But their mechanism has not yet been clarified. We investigated possible relationships between ischemic stroke and weather conditio... BACKGROUND: Weather conditions are thought to increase the risk of stroke occurrence. But their mechanism has not yet been clarified. We investigated possible relationships between ischemic stroke and weather conditions including atmospheric pressure, temperature, relative humidity, and wind speed.METHODS: One hundred and twenty-eight patients with ischemic stroke who had been admitted to our hospital between January 1 and December 31, 2010 were enrolled in this study. We investigated the relationship between daily cases and weather conditions the same day or 1, 2, and 3 days before stroke.RESULTS: A negative correlation was found between maximum wind speed and daily cases 3 days before stroke. As the relationship between daily cases and changes of weather conditions in consecutive days was evaluated, a negative correlation was found between daily cases and change of atmospheric pressure in the last 24 hours.CONCLUSIONS: The maximum wind speed 3 days before stroke and change of atmospheric pressure in the last 24 hours were found to increase the cases of ischemic stroke. We recommend that individuals at risk of ischemic stroke should pay more attention to preventive measures, especially on days with low maximum wind speed, on subsequent 3 days, and on days with low atmospheric pressure in the last 24 hours. 展开更多
关键词 weather conditions Ischemic stroke TURKEY
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Study on the Relationship between Acid Rain Characteristics and Weather Conditions in Nanchang
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作者 蔡哲 贺志明 +1 位作者 唐春燕 吴琼 《Meteorological and Environmental Research》 CAS 2010年第6期49-52,65,共5页
Based on the rainfall monitoring data and high altitude meteorological data,the present situation of acid rain pollution in Nanchang City was analyzed and the forming factors of acid rain were revealed. The results sh... Based on the rainfall monitoring data and high altitude meteorological data,the present situation of acid rain pollution in Nanchang City was analyzed and the forming factors of acid rain were revealed. The results showed that acid rain in Nanchang had the characteristics of high acidity and frequency,and the pH value of rainfall reduced in recent years,belonging to sulfuric acid type,and the most serious acid rain pollution appeared in autumn and winter. The pH value of rainfall went up with the improvement of rainfall grade,and the increase of rainfall quantity had diluting effect on the rainfall acidity. High altitude meteorological conditions affected acid rain obviously,when the upper wind velocity was below 7 m/s,the frequency of acid rain was higher and its pH value was lower,with serious acid rain pollution,and it showed that upper wind had diluting effect on the horizontal transport of pollutants. The frequency of acid rain became higher with stronger inversion intensity. Moreover,the surrounding industrial areas had obvious effect on the formation of acid rain. Unstable meteorological conditions were beneficial to the horizontal and vertical diffusion of pollution in the lower atmosphere,reducing the effect of induced-acidity pollutants on a region. 展开更多
关键词 Nanchang Acid rain weather condition pH value of rainfall China
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The Effect of Weather Conditions on Pediatric Supracondylar Humerus Fractures 被引量:1
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作者 Şükrü Demir Sefa Key Murat Gürger 《Open Journal of Orthopedics》 2021年第10期308-314,共7页
<b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="... <b><span style="font-family:Verdana;">Background:</span></b><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Environmental conditions are effective on childhood su</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">pracondylar humerus fractures. In this study</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> we evaluated the relationship between weather conditions and these fractures. </span><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> We started </span><span style="font-family:Verdana;">this study following the approval of a non-interventional research ethics</span><span style="font-family:Verdana;"> committee. Patients (<16 years) who applied to the hospital between January 2013 </span><span style="font-family:Verdana;">and July 2018 with supracondylar humerus fracture</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> were included in the</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> study. The hospital’s PROBEL system was used to diagnose (International Classification of the Diseases, ICD, S42.4) radiological images and patient information. Information on the weather conditions in the day and time period, in </span><span style="font-family:Verdana;">which supracondylar humerus fracture occurred, was obtained from TR</span><span style="font-family:Verdana;"> (Turkey) Ministry of Agriculture and Forestry General Directorate of Mete</span><span style="font-family:Verdana;">orology. The relationship between supracondylar fracture and daily weather </span><span style="font-family:Verdana;">conditions (wind, air temperature, cloudiness, and</span><span style="font-family:Verdana;"> sea</span><span><span style="font-family:Verdana;">son) was analyzed. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Most of the patients (n = 76, 40.6%, p < 0.05)</span></span><span style="font-family:Verdana;"> were fractures occurring under cloudless weather conditions. Fractures were con</span><span style="font-family:Verdana;">centrated with a second frequency in cloudy weather over 60%, except for</span><span style="font-family:Verdana;"> cloud</span><span style="font-family:Verdana;">less weather conditions (n = 51, 27.3%, p < 0.05). In the summer months </span><span style="font-family:Verdana;">when the air temperature was high, the number of fractures was higher (n = 62, 33.2%, p < 0.05) and less in the winter months (n = 24, 12.8%, p < 0.05). In hot weather conditions where the daily average temperature was above 20<span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;">&deg;</span>C, supracondylar humerus fractures were observed more (n = 101, 54%) and less than 10<span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;">&deg;</span>C (n = 43, 23%, p < 0.05). Increased incidence of fractures was observed in the </span><span><span style="font-family:Verdana;">presence of wind (n = 4, 2.1%, p < 0.05). </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Supracondylar</span></span><span style="font-family:Verdana;"> humerus fractures are </span><span style="font-family:Verdana;">common in children. Environmental conditions (temperature, wind, and</span><span style="font-family:Verdana;"> season) can be effective in the occurrence of these fractures.</span></span></span></span> 展开更多
关键词 Supracondylar Humerus Fracture Seasonal Change weather conditions Elbow Fractures
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Analysis of Weather Conditions for Aerial Security and Optimization in Maroua-Salak
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作者 Daïka Augustin Igri Moudi Pascal +1 位作者 Mounabbahou Mal Oumarou Mbane Biouele Cesar 《Atmospheric and Climate Sciences》 2022年第1期172-188,共17页
In this study, the weather conditions of the accident at Maroua-Salak airport on 02 August 2020 are analyzed. This C130 aircraft accident took place under bad weather conditions. This bad weather is diagnosed using th... In this study, the weather conditions of the accident at Maroua-Salak airport on 02 August 2020 are analyzed. This C130 aircraft accident took place under bad weather conditions. This bad weather is diagnosed using the models as CFS, GFS and GEFS that reanalyze outputs of the results. At the end of this re-analysis, the result obtained shows that the event which took place at the Maroua-Salak airport was predictable. However, the analysis of these results has made it possible to present the rainfall cumul between 05 and 10 mm for this day. In addition, a comparative study of the rainfall cumul obtained by the CFS, GFS and GEFS models and that estimated by the satellites has been carried out. These models can significantly improve the prevention of such disasters in the region. 展开更多
关键词 weather conditions Maroua-Salak Airport Models Rainfall Cumul
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Modeling of Artificial Intelligence Based Traffic Flow Prediction with Weather Conditions 被引量:3
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作者 Mesfer Al Duhayyim Amani Abdulrahman Albraikan +5 位作者 Fahd N.Al-Wesabi Hiba M.Burbur Mohammad Alamgeer Anwer Mustafa Hilal Manar Ahmed Hamza Mohammed Rizwanullah 《Computers, Materials & Continua》 SCIE EI 2022年第5期3953-3968,共16页
Short-term traffic flow prediction (TFP) is an important area inintelligent transportation system (ITS), which is used to reduce traffic congestion. But the avail of traffic flow data with temporal features and period... Short-term traffic flow prediction (TFP) is an important area inintelligent transportation system (ITS), which is used to reduce traffic congestion. But the avail of traffic flow data with temporal features and periodicfeatures are susceptible to weather conditions, making TFP a challengingissue. TFP process are significantly influenced by several factors like accidentand weather. Particularly, the inclement weather conditions may have anextreme impact on travel time and traffic flow. Since most of the existing TFPtechniques do not consider the impact of weather conditions on the TF, it isneeded to develop effective TFP with the consideration of extreme weatherconditions. In this view, this paper designs an artificial intelligence based TFPwith weather conditions (AITFP-WC) for smart cities. The goal of the AITFPWC model is to enhance the performance of the TFP model with the inclusionof weather related conditions. The proposed AITFP-WC technique includesElman neural network (ENN) model to predict the flow of traffic in smartcities. Besides, tunicate swarm algorithm with feed forward neural networks(TSA-FFNN) model is employed for the weather and periodicity analysis. Atlast, a fusion of TFP and WPA processes takes place using the FFNN modelto determine the final prediction output. In order to assess the enhancedpredictive outcome of the AITFP-WC model, an extensive simulation analysisis carried out. The experimental values highlighted the enhanced performanceof the AITFP-WC technique over the recent state of art methods. 展开更多
关键词 Smart cities artificial intelligence urban transportation deep learning weather condition TFP
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A Trend towards a Stable Warm and Windless State of the Surface Weather Conditions in Northern and Northeastern China during 1961–2014 被引量:2
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作者 Bo SUN Huijun WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第6期713-726,共14页
This study investigates the trends in the mean state and the day-to-day variability (DDV) of the surface weather conditions over northern and northeastern China (NNEC) during 1961-2014 using CN05.1 observational d... This study investigates the trends in the mean state and the day-to-day variability (DDV) of the surface weather conditions over northern and northeastern China (NNEC) during 1961-2014 using CN05.1 observational data. In this study, we show that the surface temperature (wind speed) has increased (decreased) over NNEC and that the DDV of the surface temperatures and wind speeds has decreased, indicating a trend towards a stable warm and windless state of the surface weather conditions over NNEC. This finding implies a trend towards more persistent hot and windless episodes, which threaten human health and aggravate environmental problems. The trends are also examined in reanalysis data. Both the ERA-40 and the NCEP data show an increasing (decreasing) trend in the mean state of the surface temperatures (wind speeds). However, the reanalysis data show a consistent decreasing trend in the DDV of the surface weather conditions only in the spring. The underlying reason for the decreased DDV of the surface weather conditions is further analyzed, focusing on the spring season. Essentially, the decreased DDV of the surface weather conditions can be attributed to a decrease in synoptic-scale wave activity, which is caused by a decrease in the baroclinic instability. There is a contrasting change in the baroclinic instability over East Asia, showing a decreasing (increasing) trend north (south) of 40°N. This contrasting change in the baroclinic instability is primarily caused by a tropospheric cooling zone over East Asia at approximately 40°N, which influences the meridional temperature gradient over East Asia. 展开更多
关键词 day-to-day variability surface weather condition TREND northern and northeastern China
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Modeling of the Photovoltaic Module Operating Temperature for Various Weather Conditions in the Tropical Region
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作者 Mame Cheikh Diouf Mactar Faye +2 位作者 Ababacar Thiam Alphousseyni Ndiaye Vincent Sambou 《Fluid Dynamics & Materials Processing》 EI 2022年第5期1275-1284,共10页
The operating temperature is a critical factor affecting the performances of photovoltaic(PV)modules.In this work,relevant models are proposed for the prediction of this operating temperature using data(ambient temper... The operating temperature is a critical factor affecting the performances of photovoltaic(PV)modules.In this work,relevant models are proposed for the prediction of this operating temperature using data(ambient temperature and solar irradiance)based on real measurements conducted in the tropical region.For each weather condition(categorized according to irradiance and temperature levels),the temperatures of the PV modules obtained using the proposed approach is compared with the corresponding experimentally measured value.The results show that the proposed models have a smaller Root Mean Squared Error than other models developed in the literature for all weather conditions,which confirms the reliability of the proposed framework. 展开更多
关键词 PHOTOVOLTAIC operating temperature PV module weather condition
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Performance Analysis of Curved Track G2T-FSO(Ground-to-Train Free Space Optical)Model under Various Weather Conditions
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作者 Mohammed A.Alhartomi Mohammad F.L.Abdullah +5 位作者 Wafi A.B.Mabrouk Mohammed S.M.Gismalla Ahmed Alzahmi Saeed Alzahrani Mohammad R.Altimania Mohammed S.Alsawat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第12期2087-2105,共19页
The demand for broadband data services on high-speed trains is rapidly growing as more people commute between their homes and workplaces.However,current radio frequency(RF)technology cannot adequately meet this demand... The demand for broadband data services on high-speed trains is rapidly growing as more people commute between their homes and workplaces.However,current radio frequency(RF)technology cannot adequately meet this demand.In order to address the bandwidth constraint,a technique known as free space optics(FSO)has been proposed.This paper presents a mathematical derivation and formulation of curve track G2T-FSO(Ground-to-train Free Space Optical)model,where the track radius characteristics is 2667 m,divergence angle track is 1.5°for train velocity at V=250 km/h.Multiple transmitter configurations are proposed to maximize coverage range and enhance curve track G2T-FSO link performance under varying weather conditions.The curved track G2T-FSO model was evaluated in terms of received power,signal-to-noise ratio(SNR),bit error rate(BER),and eye diagrams.The results showed maximum coverage lengths of 618,505,365,and 240 m for 4Tx/1Rx,3Tx/1Rx,2Tx/1Rx,and 1Tx/1Rx configurations,respectively.The analyzed results demonstrate that the G2T-FSO link can be effectively implemented under various weather conditions. 展开更多
关键词 Free space optics curve track ground-to-train communications geometrical loss weather conditions
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Influences of harvester and weather conditions on field loss and milling quality of rough rice 被引量:5
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作者 Ragab Khir Griffiths Atungulu +1 位作者 Ding Chao Zhongli Pan 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2017年第4期216-223,共8页
A better understanding of factors affecting field losses and milling quality during harvest is needed to improve the economic value of rice.The main objective of this study was to evaluate the impact of harvester head... A better understanding of factors affecting field losses and milling quality during harvest is needed to improve the economic value of rice.The main objective of this study was to evaluate the impact of harvester header,harvester type,and weather conditions on field loss and milling quality of rough rice.Four popular harvesters equipped with different headers:John Deere 9870 with header D60-S,John Deere 9860 with header D972-S,Hardy,and John Deere 9770 with stripper header were evaluated in this study.The header and total field losses of rice were evaluated for each harvester under regular,rainy and windy weather conditions.Tests were conducted in a rice field cultivated with medium grain rice,variety M206,at Grimes,CA.Total rice yield(TRY),head rice yield(HRY)and whiteness index(WI)were examined to evaluate the effect of weather conditions on milling quality.The obtained results revealed that the rice field loss was affected by harvester header and type,and weather conditions.Among the conventional headers,D60-S significantly reduced the rice loss compared to the D972-S and the Hardy.Harvesting with John Deere 9860 resulted in significant header and field loss compared to other tested harvesters.The average loss increased from 236.2 kg/hm^(2)and 445.2 kg/hm^(2)under regular condition to 711.1 kg/hm^(2)and 907.9 kg/hm^(2)under windy condition for John Deere 9870 and John Deere 9860,respectively.The corresponding loss percentages increased from 2.6%and 4.9%to 7.9%and 10.1%.HRY was significantly affected by weather condition at harvest time.However,the weather condition had no significant effect on TRY and WI.To minimize the rice field loss and obtain good milling quality,commercial rice harvesting during regular weather conditions is important.A proper combination of harvester type and header could be vital for reducing the rice loss. 展开更多
关键词 RICE harvesters field loss weather conditions milling quality harvester header
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Problems and Opportunities for Biometeorological Assessment of Conditions in Cold Season
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作者 Elena S.Andreeva Sergey S.Andreev 《Journal of Atmospheric Science Research》 2023年第4期77-85,共9页
The article is devoted to a discussion of the possibilities of biometeorological assessment of the severity of weather conditions during the cold season.The relevance of the study is ensured not only by the fact that ... The article is devoted to a discussion of the possibilities of biometeorological assessment of the severity of weather conditions during the cold season.The relevance of the study is ensured not only by the fact that residents of a number of states,whose total number is more than 27 million people,live in these extreme climatic conditions,but also by the need to improve biometeorological approaches to assessing the impact of these conditions on the body and health of the population.This study examined biometeorological characteristics that illustrate a measure of cold stress.These include the Siple wind-chill index;Bodman winter severity index;Arnoldi weather hardness coefficient;Mountain wind chill index;weather hardness coefficient according to I.M.Osokin.The results of a comparison of winter severity assessments based on the values of the calculated Siple and Bodman indices made it possible to establish that the Bodman index is more acceptable when assessing mildly severe winters.The most adequate for assessing the“severity”of the cold period against the background of a decrease in air temperature and an increase in wind speed is the Siple index.The need to provide the countries of the world with high-quality hydrometeorological and biometeorological forecast information is justified and relevant.In this regard,these studies are very promising. 展开更多
关键词 Biometeorological indices Severe weather Cold period of the year “rigidity”of weather conditions Cold stress Biometeorological assessment
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Feature extraction for classification of different weather conditions 被引量:1
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作者 Xudong ZHAO Peng LIU +1 位作者 Jiafeng LIU Xianglong TANG 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2011年第2期339-346,共8页
Classification of different weather conditions provides a first step support for outdoor scene modeling,which is a core component in many different applications of outdoor video analysis and computer vision.Features d... Classification of different weather conditions provides a first step support for outdoor scene modeling,which is a core component in many different applications of outdoor video analysis and computer vision.Features derived from intrinsic properties of the visual effects of different weather conditions contribute to successful classification.In this paper,features representing both the autocorrelation of pixel-wise intensities over time and the max directional length of rain streaks or snowflakes are proposed.Based on the autocorrelation of each pixel’s intensities over time,two temporal features are used for coarse classification of weather conditions according to their visual effects.On the other hand,features are extracted for fine classification of video clips with rain and snow.The classification results on 249 video clips associated with different weather conditions indicate the effectiveness of the extracted features,by using C-SVM as the classifier. 展开更多
关键词 feature extraction CLASSIFICATION RAIN SNOW illumination variation weather condition autocorrelation function
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A Study on Palaeogeography and Metallogenic Conditions of Early Carboniferous Bauxite Deposits of Old Weathered Crust in Guizhou, Sichuan, Hunan and Hubei Provinces 被引量:2
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作者 Liao Shifan Guizhou Bureau of/Geology and Mineral Resources, Guiyang, Guizhou Zhang Zhongmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第4期391-404,共14页
There are four subtypes. namely, Ia, Ib, Ic and Id of the Early Carboniferous bauxite deposits of the old weathered crust type in Guizhou, Sichuan, Hunan and Hubei provinces. They are all distributed in the Upper Yang... There are four subtypes. namely, Ia, Ib, Ic and Id of the Early Carboniferous bauxite deposits of the old weathered crust type in Guizhou, Sichuan, Hunan and Hubei provinces. They are all distributed in the Upper Yangtze old land. As a result of the Hunan-Guizhou palaeo-faulting, the crust on the northern side of the fault was uplifted and became land, thus suffering denudation. The bauxitic substances left in the weathered crust evolved and were reworked into bauxite. On the other hand, the crust on the southern side of the fault sank and remained to be part of an ocean. The bauxite deposits of Ia and Ib subtypes were formed by in-situ enrichment of residual bauxitic substances in the weathered crust of the old land, but bauxite deposits of Ic and Id subtypes resulted from transportation, accumulation and sedimentation of allothogenous bauxitic substances on the weathered crust of the old land. The processes of transportation may be distinguished as dry transportation and wet transportation, both of which proceeded under atmospheric conditions. 展开更多
关键词 A Study on Palaeogeography and Metallogenic conditions of Early Carboniferous Bauxite Deposits of Old weathered Crust in Guizhou SICHUAN
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Modeling differential car-following behavior under normal and rainy conditions: A memory-based deep learning method with attention mechanism
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作者 柏海舰 过晨晨 +3 位作者 丁恒 卫立阳 孙婷 陈星宇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期187-202,共16页
In order to analyze and learn the difference in car-following behavior between normal and rainy days, we first collect car-following trajectory data of an urban elevated road on normal and rainy days by microwave rada... In order to analyze and learn the difference in car-following behavior between normal and rainy days, we first collect car-following trajectory data of an urban elevated road on normal and rainy days by microwave radar and analyze the differences in speed, relative speed, acceleration, space headway, and time headway among data through statistics. Secondly, owing to the time-series characteristics of car-following data, we use the long short-term memory(LSTM) neural network optimized by attention mechanism(AM) and sparrow search algorithm(SSA) to learn the different car-following behaviors under different weather conditions and build corresponding models(ASL-Normal, ASL-Rain, where ASL stands for AM-SSA-LSTM), respectively. Finally, the simulation test shows that the mean square error(MSE) and reciprocal of time-to-collision(RTTC) of the ASL model are better than those of LSTM and intelligent diver model(IDM), which is closer to the real data. The ASL model can better learn different driving behaviors on normal and rainy days. However,it has a higher sensitivity to weather conditions from cross test on normal and rainy data-sets which need classification training or sample diversification processing. In the car-following platoon simulation, the stability performances of two models are excellent, which can describe the basic characteristics of traffic flow on normal and rainy days. Comparing with ASL-Rain model, the convergence time of ASL-Normal is shorter, reflecting that cautious driving behavior on rainy days will reduce traffic efficiency to a certain extent. However, ASL-Normal model produces a more severe and frequent traffic oscillation within a shorter period because of aggressive driving behavior on normal days. 展开更多
关键词 car-following behavior deep learning weather condition heterogeneous traffic flow
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Changes in the adult sex ratio of six duck species breeding populations over two decades
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作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population Population dynamics Red-listed species WATERFOWL Winter weather conditions
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Evaluations and Suggestions about Effect of Weather in Guangxi on Rice Production 被引量:5
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作者 何燕 徐世宏 +2 位作者 欧钊荣 蒋珍娇 夏小曼 《Agricultural Science & Technology》 CAS 2010年第5期49-54,105,共7页
[Objective] The paper aims to study the effect of weather on rice production in Guangxi. [Method] The authors evaluated the effect of weather and weather disasters in Guangxi on rice production by comparison and analy... [Objective] The paper aims to study the effect of weather on rice production in Guangxi. [Method] The authors evaluated the effect of weather and weather disasters in Guangxi on rice production by comparison and analysis in terms of temperature,rain and sunlight in 2009. [Result] The study summarized the main favorable and unfavorable weather conditions of rice growth,and proposed the measures and suggestions to tend to interest and avoid harm on rice production in Guangxi. [Conclusion] This study provides references to the evaluations about effect of weather in Guangxi on rice production and suggestions on how to reduce weather disasters influence and ensure rice production security. 展开更多
关键词 Rice weather conditions Effect
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Influence of Climate Conditions on Potato Yield and Studies on the Forecasting Model of Potato Yield
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作者 孙俊 李剑萍 《Agricultural Science & Technology》 CAS 2010年第4期121-123,129,共4页
[Objective]The aim was to research influence of climate conditions on potato yield and establish the forecasting model of potato yield.[Method]SPSS(Statistical Package for the Social Sciences) was used to separate p... [Objective]The aim was to research influence of climate conditions on potato yield and establish the forecasting model of potato yield.[Method]SPSS(Statistical Package for the Social Sciences) was used to separate potato output into meteorological yield and tendency yield over the years,and analysis of the relation between potato climate yield and meteorological factors was carried out.[Result]The result showed that affecting yield factor consisted of the universality and regional.The universality included vapour pressure or relative humidity of air in last August-September,precipitation in late June to early July and in mid-August;The regional is including precipitation in January and in early to mid April,vapour pressure of air in May.Prediction model about yield was established by using stepwise regression method,which qualified rates of fitting better quality.[Conclusion]Because of its long effective period,high accuracy and simplicity to dalculate,the method provided a guarantee for weather service on the crop farming of potatoes. 展开更多
关键词 Potato yield weather condition Prediction model
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The Effect of Weather and Agronomic Practice on Deoxynivalenol Mycotoxin in Durum Wheat
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作者 Isabel Giménez Jacqueline Escobar +5 位作者 Elena Ferruz Susana Lorán Marta Herrera Teresa Juan Antonio Herrera Agustin Arino 《Journal of Life Sciences》 2012年第5期513-517,共5页
Deoxynivalenol (DON) produced by Fusarium graminearum and F. culmorum in durum wheat (Triticum turgidum L. var. durum) is an important food safety issue for the cereal chain. A number of agronomic practices are kn... Deoxynivalenol (DON) produced by Fusarium graminearum and F. culmorum in durum wheat (Triticum turgidum L. var. durum) is an important food safety issue for the cereal chain. A number of agronomic practices are known to affect the infection and mycotoxin production by these Fusarium species in cereal grains. A field study was conducted to compare the natural occurrence of DON in durum wheat grown under conventional (n = 67 samples) and organic (n = 50) farming conditions during two consecutive crop years. DON mean levels were 95 and 194 μg/kg in conventional and organic durum wheat, respectively. The incidence and levels of DON were higher in the second crop year due to higher rainfall (〉 100 mm) during flowering. Overall, organically managed farming system may provide Lsome reduction in DON levels in durum wheat, which could be attributable to the lower intensity of cultivation in addition to the different system of cropping rotation. However, favourable weather conditions are likely to be more important for DON contamination than crop system. 展开更多
关键词 Agronomic factors weather conditions organic and conventional farming durum wheat mycotoxins deoxynivalenol.
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Early warning for geo-hazards based on the weather condition in China 被引量:11
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作者 Chuanzheng LIU Yanhui LIU Mingsheng WEN Can TANG Tiefeng LI Jianfa LIAN 《Global Geology》 2006年第2期131-137,共7页
According to national early warning practice for geo-hazards from 2003 to 2005,it is systematically concluded that the basic characteristics of geo-hazards,early warning method and forecast result based on the geologi... According to national early warning practice for geo-hazards from 2003 to 2005,it is systematically concluded that the basic characteristics of geo-hazards,early warning method and forecast result based on the geological maps of China in a scale 1∶6 000 000.With the contrast of different characters between sustained rainfall and typhoon rainfall inducing geo-hazards,the disaster reduction result and some problems are preliminarily analyzed.Some basic recognition is that early warning to geo-hazards is feasible,national scale forecast is only to call attention,but can't immediately be used to disaster reduction decision-making.And,the future direction is to build a united disaster reduction framework of early warning system including national,provincial and county levels based on weather factors in different scale of area. 展开更多
关键词 China geo-hazards early warning based on weather condition result analysis
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