检索结果-南通市图书馆

Simulation study on improvement of air quality by introducing electric vehicles

在线全文

学校读者我要写书评

暂无评论

International Journal of Modeling, Simulation, and Scientific Computing 2015年第4期6卷 153-163页

作者： Yiman Du jianping wu Kezhen Hu Yue Guo Department of Civil Engineering Tsinghua University Beijing 100084P.R.China†Nissan(China)investment Co.LTD Beijing100020P.R.China

Recently,Chinese megacities have suffered serious air *** studies have pointed out that transportation systems have become one of the major sources of air pollution and on-road pollutant concentrations are significantly higher than *** vehicle(EV)introduction is proposed as a method to alleviate the current *** order to better understand the benefit of the use of EVs in Beijing,a simulation platform has been developed to evaluate the improvement of air quality with the use of EVs quantitatively within the selected *** scenarios with different EV penetration rates are proposed and the results revealed 5%,10%,15%EV penetration rates which will bring about improvement of 0.86%,9.01%and 12.23%for PM2.5,0.92%,9.01%and 13.32%for nitrogen oxides(NO_(x)),0.95%,8.86%and 13.73%for CO,*** results revealed a promising improvement of air quality with the introduction of EVs.

关键词： Electric vehicle PM2.5 traffic simulation air quality

Urban air quality, meteorology and traffic linkages: Evidence from a sixteen-day particulate matter pollution event in December 2015, Beijing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2017年第9期29卷 30-38页

作者： Dongmei Hu jianping wu Kun Tian Lyuchao Liao Ming Xu Yiman Du Department of Civil Engineering Tsinghua University Fujian Key Laboratory for Automotive Electronics and Electric Drive Fujian University of Technology

A heavy 16-day pollution episode occurred in Beijing from December 19, 2015 to January 3,2016. The mean daily AQI and PM2.5 were 240.44 and 203.6 μg/m^3. We analyzed the spatiotemporal characteristics of air pollutants, meteorology and road space speed during this period, then extended to reveal the combined effects of traffic restrictions and meteorology on urban air quality with observational data and a multivariate mutual information model. Results of spatiotemporal analysis showed that five pollution stages were identified with remarkable variation patterns based on evolution of PM2.5 concentration and weather conditions. Southern sites（DX, YDM and DS） experienced heavier pollution than northern ones（DL, CP and WL）. Stage P2 exhibited combined functions of meteorology and traffic restrictions which were delayed peak-clipping effects on *** information values of Air quality–Traffic–Meteorology（ATM–MI） revealed that additive functions of traffic restrictions, suitable relative humidity and temperature were more effective on the removal of fine particles and CO than NO2.

关键词： Pollution event Air quality Meteorology Traffic restrictions Mutual information

Revisiting the TALE repeat

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2014年第4期5卷 297-306页

作者： Dong Deng Chuangye Yan jianping wu Xiaojing Pan Nieng Yan State Key Laboratory of Bio-membrane and Membrane Biotechnology Center for Structural Biology School of Life Sciencesand School of Medicine Tsinghua-Peking Center for Life Sciences Beijing 100084 China Tsinghua-Peking-NIBS Joint Program Tsinghua University Beijing 100084 China

Transcription activator-like （TAL） effectors specifically bind to double stranded （ds） DNA through a central domain of tandem repeats. Each TAL effector （TALE） repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-rec- ognition hyper-variable residue. This new numbering system is consistent with the （=-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine （A） and guanine （G） by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

关键词： TAL effectors DNA recognition plasticity

Building an IPv6 address generation and traceback system with NIDTGA in Address Driven Network

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2015年第12期58卷 14-27页

作者： LIU Ying REN Gang wu jianping ZHANG ShengLin HE Lin JIA YiHao Institute for Network Sciences and Cyberspace Tsinghua University Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and Technology Tsinghua University

In the design and construction process of Next Generation Internet, it is important to identify the source of each IP packet forwarding accurately, especially for the support of precise fine-grained management,control, traceability and improving the trustworthiness of the Internet. This paper designed a scalable Network Identity(NID) scheme for the Internet users, proposed NIDTGA(Network Identity and Time Generated Address), an IPv6 address generation algorithm embedded NID and time information, then designed and implemented an IPv6 address generation and traceback system based on NIDTGA. The design of NIDTGA, which reflects the length, time and owner attributes of the IP address, can be a good support to ADN(Address Driven Network). At the same time, by embedding the key elements of user identity and time in the IPv6 address,and by taking into account both the traceability and privacy, NIDTGA can provide a technical basis for the establishment of the network trust mechanism, and achieve the traceability of security event.

关键词： network identity IPv6 Address Driven Network IP traceback IP address generation

Finding the best answer: measuring the optimization of public and authoritative DNS

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2019年第3期62卷 208-210页

作者： Jia ZHANG Haixin DUAN Jian JIANG Jinjin LIANG jianping wu Institute for Network Science and Cyberspace Tsinghua University

Dear editor,Public domain name system (DNS) and authoritative DNS service providers have adopted various methods to optimize the accuracy of their resolution [1]. The public DNS server supports EDNS client subnet (ECS)[2], which can send the subnet information of the end users to the authoritative DNS server, and the authoritative DNS also grad-

关键词： measuring the optimization of public and authoritative DNS ECS Finding the best answer

Plant–rodent interactions after a heavy snowfall decrease plant regeneration and soil carbon emission in an old-growth forest

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Forest Ecosystems 2021年第2期8卷 403-412页

作者： Qingqiu Zhou Debao Li Shangwen Xia Zhe Chen Bo Wang jianping wu Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology Yunnan UniversityKunming 650500China Key Laboratory of Soil Ecology and Health in Universities of Yunnan Province School of Ecology and Environmental SciencesYunnan UniversityKunming 650500China Xishuangbanna Tropical Botanical Garden Chinese Academy of SciencesMengla 666303China School of Resources and Environmental Engineering Anhui UniversityHefei 230601China

Background:Climate extremes are likely to become more common in the future and are expected to change ecosystem processes and *** important consumers of seeds in forests,rodents are likely to affect forest regeneration following an extreme weather *** April 2015,we began a field experiment after an extreme snowfall event in January 2015 in a primary forest that was>300 years *** heavy snow broke many tree limbs,which presumably reduced the numbers of seeds *** treatments(rodent exclusion and rodent access)were established in the forest,in which rodent exclusion were achieved by placing stainlessness nets around the plot *** abundance,plant species richness,soil properties,soil microbial community composition,basal and substrate-induced respiration were determined in December ***:Plant abundance and species richness significantly increased,but soil microbial biomass decreased with rodent *** activity and soil basal respiration also significantly decreased with rodent *** other soil properties,however,were unaffected by rodent *** relative effects of multiple predictors of basal respiration were mainly explained by the composition of the soil microbial ***:After a heavy snowfall in an old-growth forest,exclusion of rodents increased plant regeneration and reduced microbial biomass and soil basal *** main factor associated with the reduction in soil basal respiration was the change in the composition of the soil microbial *** findings suggest that after a heavy snowfall,rodents may interfere with forest regeneration by directly reducing plant diversity and abundance but may enhance carbon retention by indirectly altering the soil microbial community.

关键词： Climate extreme PLFAs Soil respiration Forest ecosystem Enzyme activity

Aftershock sequence relocation of the 2021 M_(S)7.4 Maduo Earthquake, Qinghai, China

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2021年第8期64卷 1371-1380页

作者： Weilai WANG Lihua FANG jianping wu Hongwei TU Liyi CHEN Guijuan LAI Long ZHANG Institute of Geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Qinghai Earthquake Agency Xining 810001China

The 2021 Qinghai Maduo M_(S)7.4 earthquake was one of the strongest earthquakes that occurred in the Bayan Har block of the Tibetan Plateau during the past 30 years,which spatially filled in the gap of strong earthquake in the eastern section of the northern block *** this study,the aftershock sequence within 8 days after the mainshock was relocated by double difference *** results show that the total length of the aftershock zone is approximately 170 km;the mainshock epicenter is located in the center of the aftershock zone,indicating a bilateral *** aftershocks are mainly distributed along NWW direction with an overall strike of 285°.The focal depth profiles indicate that the seismogenic fault is nearly vertical and dips to southwest or northeast in different sections,indicating a complex *** is an aftershock gap located to the southeast of the mainshock epicenter with a scale of approximately 20 *** the eastern end of the aftershock zone,horsetaillike branch faults show the terminal effect of a large strike-slip *** is a NW-trending aftershock zone on the north side of the western section,which may be a branch fault triggered by the *** location of the aftershock sequence is close to the eastern section of the Kunlun Mountain Pass-Jiangcuo(KMPJ)*** sequence overlaps well with surface trace of the KMPJ *** speculate that the KMPJ fault is the main seismogenic fault of the M_(S)7.4 Maduo earthquake.

关键词： Maduo earthquake Aftershock sequence Double-difference location Kunlun Mountain Pass-Jiangcuo fault

Lithospheric structure beneath Ordos Block and surrounding areas from joint inversion of receiver function and surface wave dispersion

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2022年第7期65卷 1399-1413页

作者： jianping wu Yaning LIU Shijun ZHONG Weilai WANG Yan CAI Wei WANG Jing LIU Institute of Geophysics China Earthquake AdministrationBeijing 100081China Beijing Earthquake Agency Beijing 100080China

Ordos Block has undergone rapid uplift,and a series of rift basins have been formed around the block since the Cenozoic,but the formation mechanisms remain controversial.A high-resolution 3 D velocity structure of crust and mantle is important for understanding the lithospheric deformation and deep dynamic process.A here we present a 3 D S-wave velocity structure of the crust and upper mantle in the Ordos Block and surrounding regions by joint inversion of receiver functions and surface wave data from a dense broadband seismic *** lithosphere of the Ordos Block exhibits an obvious highvelocity *** the east and north of the Ordos and the southwestern part of the Tibetan Plateau,obvious low-velocity anomalies are detected in the upper mantle and extend into the *** lithosphere of the Ordos Block is thick in the center and thin at the edge,while the crust is relatively thin in the center and thick in the southwest and *** crustal thickness of the tensional basin in the north is greater than that in the central *** suggest that the outward expansion of the mantle thermal materials in eastern Tibet and the upper mantle thermal upwelling in the eastern part of the North China Craton lead to the non-uniform lithospheric thinning,temperature rise and density reduction of the Ordos *** additional buoyancy and thermodynamic effects provided by them contributed to the continuous uplift of the Ordos Block since the *** by the extrusion of Tibetan Plateau,the crustal thickening and rapid uplift occur in the southwestern and northern parts of the Ordos *** lithospheric structures of the Alxa and Ordos Blocks are different,and they may belong to different independent blocks before the Mesozoic.

关键词： Ordos North China Craton Lithospheric structure S-wave velocity structure Receiver function Surface wave

同方期刊数据库

Application of 3D Web GIS and real-time technique in earthquake information publishing and visualization

在线全文

学校读者我要写书评

暂无评论

Earthquake Science 2015年第3期28卷 223-231页

作者： Boren Li jianping wu Mao Pan Jing Huang Institute of Geophysics China Earthquake Administration School of Earth and Space Sciences Peking University

In hazard management, earthquake researchers have utilized GIS to ease the process of managing *** use Web GIS to assess hazards and seismic risk. Although they can provide a visual analysis platform based on GIS technology, they lack a general description in the extensibility of Web GIS for processing dynamic data,especially real-time data. In this paper, we propose a novel approach for real-time 3D visual earthquake information publishing model based on Web GIS and digital globe to improve the ability of processing real-time data in systems based on Web GIS. On the basis of the model, we implement a real-time 3D earthquake information publishing system—Eq Map3 D. The system can not only publish realtime earthquake information but also display these data and their background geoscience information in a 3D scene. It provides a powerful tool for display, analysis, and decisionmaking for researchers and administrators. It also facilitates better communication between researchers engaged in geosciences and the interested public.

关键词： Earthquake Real time irtual globe Web GIS