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Science China Earth Sciences 2011年第7期54卷 1095-1104页

作者： SHEN BaiZhu LIN ZhongDa LU RiYu lian yi Institute of Meteorological Science of Jilin Province Changchun 130062 China Laboratory of Research for Mid-High Latitude Circulation System and East Asian Monsoon Changchun 130062 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Summer rainfall is vital for crops in Northeast China. In this study, we investigated large-scale circulation anomalies related to monthly summer rainfall in Northeast China using European Center for Medium-Range Weather Forecast ERA-40 reanalysis data and monthly rainfall data from 79 stations in Northeast China. The results show that the interannual variation in rainfall over Northeast China is mainly dominated by a cold vortex in early summer (May-June) and by the East Asian summer monsoon in late summer (July-August). In early summer, corresponding to increased rainfall in Northeast China, an anomalous cyclonic anomaly tilted westward with height appears to the northwest and cold vortices occur frequently. In late summer, the rainfall anomaly is mainly controlled by a northward shift of the local East Asian jet stream in the upper troposphere and the northwest extension of the western Pacific subtropical high (WPSH) in the lower troposphere. The enhanced southwesterly anomaly in the west of the WPSH transports more moisture into Northeast China and results in more rainfall. In addition, compared with that in July, the rainfall in Northeast China in August is also influenced by a mid- and high-latitude blocking high over Northeast Asia.

关键词： summer rainfall Northeast China interannual variation cold vortex western Pacific subtropical high East Asian jetstream

Measurement of the distance from grain divider to harvesting boundary based on dynamic regions of interest

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 226-232页

作者： Jin Chen Jie Song Zhuohuai Guan yi lian College of Mechanical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Synergistic Innovation Center of Jiangsu Modern Agricultural Equipment and Technology Zhenjiang 212013JiangsuChina

Combine harvesters need to work along the crop boundary line during *** deviation(the distance between the grain divider and the harvesting boundary line)is important navigation *** the measurement accuracy and real-time performance of lateral deviation is an effective way to improve navigation *** at the problems of poor real-time performance and low measurement accuracy of existing lateral deviation measurement methods,a method of dynamic selection of the region of interest in the process of image processing was proposed and verified by field *** calculation of lateral deviation includes the following stages:analyzing the average gray value of each column in the field image;drawing dynamic region of interest using maximum average gray value;extracting the rice boundary line by using the probabilistic Hough transform algorithm;predicting the location of the boundary line by using the Kalman filter algorithm;measuring the lateral deviation by using the inverse perspective transform *** analysis of images under different rice fields showed that the method can effectively identify crop boundary *** to the test results of calling cameras in different installation positions,the highest extraction success rate of the boundary line was 96.9%,the average success rate was 94.8%,and the speed of real-time measurement of lateral deviation was 0.065 s/*** the driving speed was 0.4 m/s,the detection error of linear tracking detection was less than 4.3 *** the increase of speed,the error gradually *** algorithm has a good real-time performance and high accuracy during low-speed driving.

关键词： distance harvesting boundary dynamic region of interest combine harvester measurement

Numerical Experiments on the Impact of Spring North Pacific SSTA on NPO and Unusually Cool Summers in Northeast China

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Advances in Atmospheric Sciences 2014年第6期31卷 1305-1315页

作者： lian yi ZHAO Bin SHEN Baizhu LI Shangfeng LIU Gang Laboratory of Research for Middle–High Latitude Circulation Systems and East Asian Monsoon Institute of Meteorological Sciences of Jilin Province National Meteorological Center Jilin Meteorological Science and Technology Service Center

A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold （warm） El Ni（n）o （La Ni（n）a） phases in the Ni（n）o4 region and sea surface temperature anomalies （SSTA） in the westerly drifts region would result in abnormally enhanced NorthEast Cold Vortex （NECV） activities in early *** spring,the central equatorial Pacific El Ni（n）o phase and westerly drift SSTA forcing would lead to the retreat of non-adiabatic waves,inducing elliptic low-frequency anomalies of tropical air *** would enhance the anomalous cyclone-anticyclonecyclone-anticyclone low-frequency wave train that propagates from the tropics to the extratropics and further to the mid-high latitudes,constituting a major physical mechanism that contributes to the early summer circulation anomalies in the subtropics and in the North Pacific mid-high *** central equatorial Pacific La Ni（n）a forcing in the spring would,on the one hand,induce teleconnection anomalies of high pressure from the Sea of Okhotsk to the Sea of Japan in early summer,and on the other hand indirectly trigger a positive low-frequency East Asia-Pacific teleconnection （EAP） wave train in the lower troposphere.

关键词： atmospheric model westerly drifts Ni(n)o4 SSTA low-frequency variation circulation pattern cool summer Northeast China

Development of a monitoring system for grain loss of paddy rice based on a decision tree algorithm

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International Journal of Agricultural and Biological Engineering 2021年第1期14卷 224-229页

作者： yi lian Jin Chen Zhuohuai Guan Jie Song College of Mechanical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Synergistic Innovation Center of Jiangsu Modern Agricultural Equipment and Technology Zhenjiang 212013JiangsuChina

China has the world’s largest planting area of paddy rice,but large quantities of paddy rice fall to the ground and are lost during harvesting with a combine *** grain loss is an effective way to increase production and *** this study,a monitoring system was developed to monitor the grain loss of the paddy rice and this approach was tested on the test bench for verifying the *** development of the monitoring system for grain loss included two stages:the first stage was to collect impact signals using a piezoelectric film,extract the four features of Root Mean Square,Peak number,Frequency and Amplitude(fundamental component),and identify the kernel impact signals using the J48(C4.5)Decision Tree *** the second stage,the precision of the monitoring system was tested for the paddy rice at three different moisture contents(10.4%,19.6%,and 30.4%)and five different grain/impurity ratios(1/0.5,1/1,1/1.5,1/2,and 1/2.5).According to the results,the highest monitoring accuracy was 99.3%(moisture content 30.8%and grain/impurity ratio 1/2.5),the average accuracy of the monitoring tests was 92.6%,and monitoring of grain/impurity ratios between 1/1 and 1/1.5(>95.4%)had higher accuracy than monitoring the other grain/impurity *** accuracy decreased as impurities *** lowest accuracy for grain loss monitoring was obtained when the grain/impurity ratio was 1/2.5,with monitoring accuracies of 88.2%,75.7%and 78.8%at moisture contents of 10.4%,19.6%and 30.4%.

关键词： monitoring system combine harvester paddy rice grain loss sensor data mining decision tree development

Bias correction and projection of surface air temperature in LMDZ multiple simulation over central and eastern China

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Advances in Climate Change Research 2018年第1期9卷 81-92页

作者： GUO lian-yi GAO Qian JIANG Zhi-Hong Laurent LI Key Laboratory of Meteorological Disaster Ministry of EducationJoint International Research Laboratory of Climate and Environment ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044Chin Jiaxiang County Meteorological Service Jining 272400China Laboratory of Meteorological Dynamics UPMC/CNRSIPSLParis 75005France

Based on LMDZ4 daily temperature dataset,equidistant cumulative distribution function matching method(EDCDFm)and cumulative distribution function-transform method(CDF-t)are used to evaluate the ability of models in simulating extreme temperature over central and eastern *** future temperature change is then *** results show that the EDCDFm and CDF-t methods function effectively correct the spatial distribution of daily mean temperature and extreme temperature,significantly reduce the biases of the model simulation and effectively improve the capacity of models for spatial pattern of extreme ***,the cold bias of the CDF-t method in winter is obviously higher than that of the EDCDFm method,and the temperature change curve of the EDCDFm method is closer to the observation than that of the CDF-t *** projection based on the EDCDFm method shows that under the RCP4.5 emission scenario,the temperature in the study area shows a warming *** to 1986e2005,the mean temperature is projected to increase by 0.76,1.84,and 2.10℃during 2017e2036,2046e2065,and 2080e2099,*** spatial change for the mean,maximum,and minimum temperature in the three future periods have good consistency;warming in northern China is higher than that in the *** in temperature projection are large in the Tibetan Plateau and Sichuan *** days decrease significantly,especially in the Tibetan Plateau,and the frost days in the three periods decrease by more than 15,30,and 40 d,*** variation of heat wave indice is the smallest;the increase of heat wave is mainly in eastern China,and the increase in South China is more than 2 ***,under the global warming of 1.5℃and 2℃,the response characteristics of extreme temperature over central and eastern China are also *** results show that the mean temperature,maximum temperature and minimum temperature in the study area increase by more than 0.75℃under 1.5℃target

关键词： EDCDFm method CDF-T method Future temperature projection 1.5℃and 2℃global warming

Comparison of dental pulp periodontal therapy and conventional simple periodontal therapy as treatment modalities for severe periodontitis

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World Journal of Clinical Cases 2021年第33期9卷 10098-10105页

作者： Lu Li Hong-Jie Chen yi lian Tuo Wang Department of Stomatology The Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Stomatology Wuhou District People's Hospital of ChengduChengdu 610041Sichuan ProvinceChina Department of Stomatology Chengdu Children Special HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND Severe periodontitis is a major oral health concern today as it can lead to loss of *** periodontal therapy has numerous pitfalls as it does not address the pulp-periodontal complex in its *** To investigate the effect of dental pulp periodontal therapy on the levels of interleukin-1β(IL-1β)and IL-10 in gingival crevicular fluid(GCF)in patients with severe *** Eighty-six patients with severe periodontitis were randomly divided into a research group(n=43)and a control group(n=43).The control group was treated with simple periodontal therapy,and the research group was treated with dental pulp periodontal *** total effective rates of the treatments;periodontal status before and after treatment through the measurement of the periodontal pocket probing depth(PPD),gingival sulcus bleeding index(SBI),mobility(MD),and plaque index(PLI);the levels of inflammatory factors IL-1βand IL-10 in the GCF;and the incidence of complications were calculated for both groups and compared using the Student’s t test and theχ^(2) *** The total effective rate of treatment in the study group(93.02%)was higher than that in the control group(76.74%;P<0.05).While before treatment,there was no significant difference in the PLI,MD,SBI,or PPD between the two groups,the post-treatment values of PLI,MD,SBI,and PPD(4.71±0.16 mm,0.61±0.09 mm,0.96±0.17 mm,and 0.76±0.26 mm,respectively)were significantly lower(P<0.05)in the research group than in the control group(5.35±0.24 mm,0.93±0.15 mm,1.35±0.30 mm,and 1.04±0.41 mm,respectively).There was no significant difference in the level of IL-1βor IL-10 in the GCF before treatment between the two groups;after treatment,the IL-1βlevel in the research group(139.04±15.54 pg/mL)was significantly lower than that in the control group(156.35±18.10 pg/mL),and the level of IL-10 in the research group(7.98±1.01 ug/L)was higher than that in the control group(5.56±0.96 ug/L)(P<0.05).The incidence of com

关键词： Severe periodontitis Dental pulp and periodontal therapy Interleukin-1β Interleukin-10

A 20 μW 95 dB dynamic range 4th-order Delta-Sigma modulator with novel power efficient operational transconductance amplifier and resonator

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第6期12卷 486-498页

作者： Jian XU Xiao-bo WU Meng-lian ZHAO Jun-yi SHEN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

A low power high performance Delta-Sigma modulator for portable measurement applications is presented. To reduce power consumption while maintaining high performance, a fully feedforward architecture with a comprehensive system-level design is implemented. As a key building block, a novel power efficient current mirror operational transconductance amplifier (OTA) with a fast-settling less-error switched-capacitor common-mode feedback (SC CMFB) circuit is introduced, and the effects of both gain nonlinearity and 1/f noise of OTA are discussed. A new method to determine the voltage gain of an OTA is also proposed. The bottom terminal parasitic effect of poly-insulator-poly (PIP) capacitors is considered. About an extra 20% of capacitance is added to the total capacitance load. A power and area efficient resonator is adopted to realize a coefficient of 1/90 for 50% power and 75% area reduction compared with conventional designs. The chip is implemented in a low cost 0.35 μm complementary metal oxide semiconductor (CMOS) process. The total power consumption is 20 μW with a 1.5 V supply, and the measured dynamic range (DR) is 95 dB over a 1 kHz bandwidth. Experimental results show that a high figure-of-merit (FOM) is achieved for the designed modulator in comparison with those from the literature.

关键词： Low power High performance Power efficient OTA and resonator Delta-Sigma modulator

Interannual Variability of Summer Rainfall over the Northern Part of China and the Related Circulation Features

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Journal of Meteorological Research 2016年第5期30卷 615-630页

作者： BUEH Cholaw LI Yan LIN Dawei lian yi International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 College of Atmosphere Science Chengdu University of Information Technology Chengdu 610225 University of Chinese Academy of Sciences Beijing 100049 Laboratory of Research for Middle High Latitude Circulation and East Asian Monsoon Changchun 130062 Institute of Meteorological Sciences of Jilin Province Changchun 130062

In this study, interannual variability of summer rainfall over the northern part of China （NPC） and associated circulation patterns were investigated by using long-term （1961-2013） observational and reanalysis data. Two important NPC rainfall modes were identified by empirical orthogoual function analysis： the first is characterized by an almost uniformly distributed rainfall anomaly over most parts of the NPC, while the second shows rainfall variability in Northeast China （NEC） and its out-of-phase relationship with that in North China （NC） and the northern part of Northwest China. The results also suggest that the NPC summer rainfall anomalies are also closely associated with those in some other parts of China. It is revealed that the circumglobal teleconnection pattern associated with the anomalous Indian summer monsoon （ISM） and the Polar/Eurasia （PEA） pattern work in concert to constitute the typical circulation pattern of the first rainfall mode. The cooperative engagement of the anomalous ISM circulation and the PEA pattern is fundamental in transporting water vapor to the NPC. The study emphasizes that the PEA pattern is essential for the water vapor transport to the NPC through the anomalous midlatitude westerly. In the second NPC rainfall mode, the typical circulation pattern is characterized by the anomalous surface Okhotsk high and the attendant lower tropospheric circulation anomaly over NEC. The circulation anomaly over NEC leads to a redistribution of water vapor fluxes over the NPC and constitutes an out-of-phase relationship between the rainfall anomalies over NEC and NC.

关键词： summer rainfall northern part of China circumglobal teleconnection pattern Polar/Eurasia pattern water vapor transport

Peroxymonosulfate activation based on Co_(9)S_(8)@N-C:A new strategy for highly efficient hydrogen production and synchronous formaldehyde removal in wastewater

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Journal of Materials Science & Technology 2022年第32期127卷 256-267页

作者： Caiyan Gao Xuezhen Feng lian yi Xiaoyong Wu Renji Zheng Gaoke Zhang Yubiao Li School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

Formaldehyde(FA),as an important chemical raw material,has been widely used in many ***,the discharge of a large amount of FA-containing wastewater poses a serious threat to the environment and human ***,the in-situ hydrogen energy release technology of hydrogen-containing stable liquid has been extensively explored due to its safe *** a robust method to achieve FA removal and synchronous in-situ hydrogen release from FA containing wastewater is of great significant for environmental protection and energy crisis ***,we have innovatively introduced peroxymonosulfate(PMS)activation technology into FA removal and hydrogen production *** composite of nitrogen doped carbon coating Co_(9)S_(8)nanotubes(Co_(9)S_(8)@N-C)is employed as a proof of concept for FA decomposition and simultaneously hydrogen production based on PMS activation *** expected,the Co_(9)S_(8)@N-C/PMS system presents much superior hydrogen production efficiency and satisfactory FA removal rate towards FA wastewater than those of common catalysis,photocatalysis and Fenton reaction in the basic condition in a wide range of FA *** hydrogen yield reaches a value as high as 471μmol within 60 min,corresponding to a FA degradation rate of 30%with an initial FA concentration of 0.722 mol L^(-1).Characterizations and density functional theory(DFT)calculations suggest that the free radical process dominated by superoxide radical(O_(2)·^(-))and nonradical process dominated by singlet oxygen(^(1)O_(2)),which are induced by Co_(9)S_(8)@N-C/PMS system,are responsible for highly efficient hydrogen production via FA *** generated O_(2)·^(-)and ^(1)O_(2)can extract·H from FA to form·OOH intermediate,which can further combine with the·H from water to produce *** study provides an applicable technique for environmental purification and new energy development based on FA containing wastewater.

关键词： Peroxymonosulfate activation Co9S8@N–C Hydrogen evolution Formaldehyde removal

Interdecadal Variations of Cold Air Activities in Northeast China during Springtime

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Journal of Meteorological Research 2016年第5期30卷 645-661页

作者： LI Shangfeng JIANG Dabang lian yi YAO Yaoxian Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Laboratory of Research for Middle High Latitude Circulation and East Asian Monsoon Institute of Meteorological Sciences of Jilin Province Changchun 130062 Jilin Meteorological Bureau Changchun 130062 University of Chinese Academy of Sciences Beijing 100049

Based on the daily mean temperature data of CN05.2 from 1961 to 2012, cold events （CEs） are first divided into two categories according to their duration： strong cold events （SCEs） and weak cold events （WCEs）. Then, the characteristics of CEs, SCEs, and WCEs during springtime are investigated. The results indicate that in the pre-1990s epoch, ENSO and Arctic Oscillation events in the previous winter are closely related to SCEs in the following spring. The multidecadal variations of CEs, SCEs, and WCEs are obvious. The intensity trend for SCEs is significantly negative, but it seems less apparent for WCEs. Further analysis reveals that when both SCEs and WCEs occur, a typical East Asian trough in the 850- hPa wind field, whose northwesterly wind component invades Northeast China （NEC） and causes freezing days, can be found in every decade. For the SCEs, a cold vortex, with its center located over Okhotsk and northeasterly current affecting NEC, is found as an additional feature. For the WCEs, the cold vortex is located in Karafuto and its northwesterly airflow intrudes into NEC. As for the difference between SCEs and WCEs, the northwestern flow is weaker while the northeastern counterpart is stronger during the SCEs, in all decades. In the Takaya-Nakamura flux and divergence fields, for the SCEs, a divergence center exists over NEC; and over its downstream regions, a stronger divergence center appears, not like a wave train. However, the opposite is the case for the WCEs; moreover, the wave train appears clearly during the WCEs, which means that the wave energy can propagate and dissipate more easily during WCEs.

关键词： cold events East Asian trough interdecadal variability wave flux ENSO Arctic Oscillation