期刊文献+
共找到343篇文章
< 1 2 18 >
每页显示 20 50 100
Impacts of forest plantation programs on sectoral CO_(2) emissions regionally in New Zealand
1
作者 Saeed Solaymani Andrew Dunningham 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期13-28,共16页
Investing in projects that support environmental benefits,such as tree harvesting,has the potential to reduce air pollution levels in the atmosphere in the future.However,this kind of investment may increase the curre... Investing in projects that support environmental benefits,such as tree harvesting,has the potential to reduce air pollution levels in the atmosphere in the future.However,this kind of investment may increase the current level of emissions.Therefore,it is necessary to estimate how much the policy affects the current level of CO_(2) emissions.This makes sure the policy doesn’t increase the level of CO_(2) emis-sions.This study aims to analyze the effect of the One Bil-lion Trees program on CO_(2) emissions in New Zealand by employing the 2020 input–output table analysis.This inves-tigation examines the direct and indirect effects of policy on both the demand and supply sides across six regions of New Zealand.The results of this study for the first year of plantation suggest that the policy increases the level of CO_(2) emissions in all regions,especially in the Waikato region.The direct and indirect impact of the policy leads to 64 kt of CO_(2) emissions on the demand side and 270 kt of CO_(2) emis-sions on the supply side.These lead to 0.19 and 0.74%of total CO_(2) emissions being attributed to investment shocks.Continuing the policy is recommended,as it has a low effect on CO_(2) emissions.However,it is crucial to prioritize the use of low-carbon machinery that uses fossil fuels during the plantation process. 展开更多
关键词 regional input–output analysis Forest investment program Sectoral CO_(2) emissions Environmental policies Supply-side policy Demand-side policy
在线阅读 下载PDF
Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
2
作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation regional large-scale Online recognition Feature extraction method
在线阅读 下载PDF
Hyperbolic map unravels eight regions in temperature volatility regionalization of China' Mainland
3
作者 Yuxuan Song Changgui Gu +4 位作者 Muhua Zheng Aixia Feng Yufei Xi Haiying Wang Huijie Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第12期526-534,共9页
Abrupt temperature volatility has detrimental effects on daily activities,macroeconomic growth,and human health.Predicting abrupt temperature volatility and thus diminishing its negative impacts can be achieved by exp... Abrupt temperature volatility has detrimental effects on daily activities,macroeconomic growth,and human health.Predicting abrupt temperature volatility and thus diminishing its negative impacts can be achieved by exploring homogeneous regions of temperature volatility and analyzing the driving factors.To investigate the regionalization of temperature volatility in China's mainland,a network constructed by the cosine similarity of temperature volatility series from China's mainland was embedded in hyperbolic space.Subsequently,we partitioned the network on the hyperbolic map using the critical gap method and then found eight regions in all.Ultimately,a network of communities was constructed while the interaction among communities was quantified.This yields a perspective of temperature volatility regionalization that can accurately reflect factors including altitude,climate type,and the geographic location of mountains.Further analysis demonstrates that the regionalization in the hyperbolic map is distinct from provinces and has a realistic basis:communities in southwest China show strong correlations due to the temperature sensitivity to altitude,and communities in northern China show a convergence in the area of Dingxi,Gansu,mainly owing to the strong temperature sensitivity to climate types.As a consequence,node distributions and community divisions in the hyperbolic map can offer new insights into the regionalization of temperature volatility in China's mainland.The results demonstrate the potential of hyperbolic embedding of complex networks in forecasting future node associations in real-world data. 展开更多
关键词 complex network hyperbolic embedding community detection regionalIZATION
在线阅读 下载PDF
Empirical Research on the Competence of Intellectual Property Rights in Shenzhen Based on Regional Industrial Innovation 被引量:1
4
作者 李平 李蓉 +1 位作者 萧延高 蔡晓红 《Journal of Electronic Science and Technology of China》 2006年第4期345-349,452,共6页
Based on statistical data of the regional industry and the level of intellectual property right (IPR) development, this paper adopts the ways such as regression analysis and description statistics, trying to analyze... Based on statistical data of the regional industry and the level of intellectual property right (IPR) development, this paper adopts the ways such as regression analysis and description statistics, trying to analyze the intrinsic linkage among the regional industry innovation, regional competence and IPR competence. A conclusion was drawn that IPR competence can assuredly upgrade the industrial competence and regional competence, but the supporting from perfect institutional environment and service system of intellectual property rights (IPR) is yet needed. According to the analysis, this paper gives some suggestions on how to improve the IPR competence of Shenzhen, 展开更多
关键词 regional industrial innovation intellectual property competence regional competence regressions
在线阅读 下载PDF
Based on Design Method of Regional Architecture
5
作者 朱海声 《海外英语》 2012年第13期275-276,共2页
In face of energy crisis,raw materials exhaustion,environmental pollution and other environmental issues caused by the current social and economic development model,theory and method of regional architecture have been... In face of energy crisis,raw materials exhaustion,environmental pollution and other environmental issues caused by the current social and economic development model,theory and method of regional architecture have been noted and studied by persons in the field of architecture and ecology.In the paper,the author analyzes architectural region,interprets regional architecture of Mario Botta and summarizes organic theory with a view to recognizing the importance of regional architecture method and reflecting on the significance of architectural region theories at the present times under the background of current globalization and information era. 展开更多
关键词 REGION NEW regional ARCHITECTURE Mario Botta ORGAN
在线阅读 下载PDF
Regional Differences of the Urinary Proteomes in Healthy Chinese Individuals 被引量:2
6
作者 吴建强 秦伟伟 +4 位作者 潘利 王小蓉 张彪 单广良 高友鹤 《Chinese Medical Sciences Journal》 CAS CSCD 2019年第3期157-167,共11页
Objective Urine is a promising biomarker source for clinical proteomics studies.Regional physiological differences are common in multi-center clinical studies.In this study,we investigate whether significant differenc... Objective Urine is a promising biomarker source for clinical proteomics studies.Regional physiological differences are common in multi-center clinical studies.In this study,we investigate whether significant differences are present in the urinary proteomes of individuals from different regions in China.Methods In this study,morning urine samples were collected from healthy urban residents in three regions of China(Haikou,Xi’an and Xining)and urinary proteins were preserved using a membrane-based method(Urimem).The urine proteomes of 27 normal samples were analyzed using LC-MS/MS and compared among three regions.Functional annotation of the differential proteins among the three areas was analyzed using the DAVID online database,and pathway enrichment of the differential urinary proteins was analyzed using KEGG.Results We identified 1898 proteins from Urimem samples using label-free proteome quantification,of which 56 urine proteins were differentially expressed among the three regions(P<0.05).Hierarchical clustering analysis showed that inter-regional differences caused less significant changes in the urine proteome than intersex differences.After gender stratification,16 differential proteins were identified in male samples and 84 differential proteins were identified in female samples.Among these differential proteins,several proteins have been previously reported as urinary disease biomarkers.Conclusions Urimem will facilitate urinary protein storage for large-scale urine sample collection.Regional differences are a confounding factor influencing the urine proteome and should be considered in future multicenter biomarker studies. 展开更多
关键词 URINE PROTEOMICS BIOBANK biomarkers regional differences
在线阅读 下载PDF
Regional differences of water conservation in Beijing’s forest ecosystem 被引量:11
7
作者 ZHANG Biao XIE Gao-di YAN Yu-ping YANG Yan-gang 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期295-300,共6页
The water conservation capacities of main forests in Beijing,China were estimated through the quantitative analysis.Various methods developed in published papers on forest hydrology were employed.The forests in Huairo... The water conservation capacities of main forests in Beijing,China were estimated through the quantitative analysis.Various methods developed in published papers on forest hydrology were employed.The forests in Huairou,Yanqing,Miyun,Mentougou and Fangshan districts are the main contributors to water conservation(the cumulative ratio reaches 65%),and the forests in Tongzhou,Chaoyang,Shunyi and Daxing districts have the highest water conservation capacity(3000 m3/ha).Altitude and slope are the key factors to affect the water conservation capacity.The forests located in Plain Area,Hilly Area,Low Mountain,and Middle Mountain contributes 27%,28%,24% and 21% of the conserved water,respectively.The water conservation capacity of forests in Plain Area(2 948 m3/ha),is superior to the forests in other regions.And the forests situated on Flat Slope,Moderate Slope and Gentle Slope constitute the largest proportion(nearly 93%) of water conservation,while the forests on Flat Slope has the highest water conservation capacity(2 797 m3/ha),and the forest on Steep slope has the lowest water conservation capacity(948 m3/ha). 展开更多
关键词 forest ecosystem regional difference water conservation BEIJING
在线阅读 下载PDF
Spatial and temporal patterns of the sensitivity of radial growth response by Picea schrenkiana to regional climate change in the Tianshan Mountains 被引量:10
8
作者 Zhongtong Peng Yuandong Zhang +6 位作者 Liangjun Zhu Mingming Guo Qingao Lu Kun Xu Hui Shao Qifeng Mo Shirong Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1669-1681,共13页
Climate change significantly impacts forest ecosystems in arid and semi-arid regions.However,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipita... Climate change significantly impacts forest ecosystems in arid and semi-arid regions.However,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipitation in north-west China is unclear.The dendrochronological method was used to study climate response sensitivity of radial growth of Picea schrenkiana from 158 trees at six sites during 1990-2020.The results show that climate warming and increased precipitation significantly promoted the growth of trees.The response to temperature first increased,then decreased.However,the response to increased precipitation and the self-calibrating Palmer Drought Severity Index(scPDSI)increased significantly.In most areas of the Tianshan Mountains,the proportion of trees under increased precipitation and scPDSI positive response was relatively high.Over time,small-diameter trees were strongly affected by drought stress.It is predicted that under continuous warming and increased precipitation,trees in most areas of the Tianshan Mountains,especially those with small diameters,will be more affected by precipitation. 展开更多
关键词 regional climate change Picea schrenkiana Climate response sensitivity Spatiotemporal patterns Tianshan mountains
在线阅读 下载PDF
Satellite Constellation Design with Multi-Objective Genetic Algorithm for Regional Terrestrial Satellite Network 被引量:12
9
作者 Cuiqin Dai Guimin Zheng Qianbin Chen 《China Communications》 SCIE CSCD 2018年第8期1-10,共10页
Constellations design for regional terrestrial-satellite network can strengthen the coverage for incomplete terrestrial cellular network. In this paper, a regional satellite constellation design scheme with multiple f... Constellations design for regional terrestrial-satellite network can strengthen the coverage for incomplete terrestrial cellular network. In this paper, a regional satellite constellation design scheme with multiple feature points and multiple optimization indicators is proposed by comprehensively considering multi-objective optimization and genetic algorithm, and "the Belt and Road" model is presented in the way of dividing over 70 nations into three regular target areas. Following this, we formulate the optimization model and devise a multi-objective genetic algorithm suited for the regional area with the coverage rate under simulating, computing and determining. Meanwhile, the total number of satellites in the constellation is reduced by calculating the ratio of actual coverage of a single-orbit constellation and the area of targets. Moreover, the constellations' performances of the proposed scheme are investigated with the connection of C++ and Satellite Tool Kit(STK). Simulation results show that the designed satellite constellations can achieve a good coverage of the target areas. 展开更多
关键词 regional terrestrial-satellite net-work constellation design multi-objective optimization genetic algorithm coverage performance
在线阅读 下载PDF
Evaluation of Land-Use Efficiency Based on Regional Scale——A Case Study in Zhanjiang,Guangdong Province 被引量:8
10
作者 CHEN Shi-yin LIU Yao-lin CHEN Cui-fang 《Journal of China University of Mining and Technology》 EI 2007年第2期215-219,共5页
Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,econom... Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,economy,ecology and environment. The weight of each indicator was defined by an analytical hierarchy process (AHP) and the entropy method (EM). Then,a case study in Zhanjiang was carried out to analyze the regional land use efficiency from 1996 to 2004 and its development by using the method of multifactor composite evaluation and an analytical model of the de-gree of coordination. The results indicate that land use efficiency with respect to society and the economy improved,whereas the ecological and environmental efficiencies were found to decrease. The degree of coordination in Zhanjiang is still at the status of basic coordination. Finally,measures for enhancing the ecological and environmental establish-ment are suggested in order to improve the regulations of land use structure and patterns,establish ecological forests for the public good and green corridors and prevent the soil erosion. 展开更多
关键词 regional scale land-use efficiency degree of coordination EVALUATION
在线阅读 下载PDF
Assessment of the effects of the shelterbelt on the soil temperature at regional scale based on MODIS data 被引量:3
11
作者 DENG Rong-xin LI Ying +2 位作者 ZHANG Shu-wen WANG Wen-juan SHI Xiao-liang 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期65-70,共6页
At present, the most researches on the protected effect of shelterbelt are on the basis of the two scales of forest belts and networks. However, with the further research on the global environmental change, more atten... At present, the most researches on the protected effect of shelterbelt are on the basis of the two scales of forest belts and networks. However, with the further research on the global environmental change, more attention was paid to the regional climate effect of shelterbelt. In present study, we analyzed the temperature effect of the shelterbelt at regional scale by using the land surface temperature (LST) data from the moderate resolution imaging spectroradiometer (MODIS) at Yushu, Nong'an, Dehui, and Fuyu in Jilin Province of China from March to October in 2008. Results show that the shelterbelt can increase the soil temperature of the protected farmland as compared with no shelterbelt zone, with the increment of 0.57oC per day in fine shelterbelt and 0.38oC per day in the normal shelterbelt. Moreover, the correlation analysis of the air temperature, precipitation and the soil type and the shelterbelt effect shows that the air temperature and precipitation are negatively correlated with the shelterbelt effects, that is, the more the temperature and precipitation are, the less the effect produced. While the impact of the soil types on the shelterbelt's effect is not very obvious as a whole. This paper draws significance in terms of analyzing the effects of the shelterbelt on the soil temperature at regional scale utilizing the remotely sensed data and GIS technique. 展开更多
关键词 regional scale remote sensing SHELTERBELT temperature effect
在线阅读 下载PDF
Variations in the biomass of Eucalyptus plantations at a regional scale in Southern China 被引量:2
12
作者 Quanyi Qiu Guoliang Yun +6 位作者 Shudi Zuo Jing Yan Lizhong Hua Yin Ren Jianfeng Tang Yaying Li Qi Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1263-1276,共14页
We quantified deviations in regional forest biomass from simple extrapolation of plot data by the biomass expansion factor method(BEF) versus estimates obtained from a local biomass model,based on large-scale empiri... We quantified deviations in regional forest biomass from simple extrapolation of plot data by the biomass expansion factor method(BEF) versus estimates obtained from a local biomass model,based on large-scale empirical field inventory sampling data.The sources and relative contributions of deviations between the two models were analyzed by the boosted regression trees method.Relative to the local model,BEF overestimated accumulative biomass by 22.12%.The predominant sources of the total deviation (70.94%) were stand-structure variables.Stand age and diameter at breast height are the major factors.Compared with biotic variables,abiotic variables had a smaller overall contribution (29.06%),with elevation and soil depth being the most important among the examined abiotic factors.Large deviations in regional forest biomass and carbon stock estimates are likely to be obtained with BEF relative to estimates based on local data.To minimize deviations,stand age and elevation should be included in regional forest-biomass estimation. 展开更多
关键词 BEF Boosted regression trees Eucalyptus plantations Local biomass model regional biomass estimation Biotic versus abiotic factors Uncertainty analysis
在线阅读 下载PDF
Evaluation on Regional Ecological Benefits of Windbreak Systems 被引量:1
13
作者 宫伟光 张国珍 +1 位作者 向开馥 赵雨森 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第3期148-151,共4页
This paper studied how dynamically to evaluate regional ecological benefits of windbreak systems in a county scale. Data of air temperature. humidity. wind speed, crop yield and forest cover percentage were investigat... This paper studied how dynamically to evaluate regional ecological benefits of windbreak systems in a county scale. Data of air temperature. humidity. wind speed, crop yield and forest cover percentage were investigated and collected in some of counties of Heilongjiang Province, where windbreak systems were established in the last thirty years. Through analysis, an evaluation index system estimating regional ecological benetits of windbreak systems was set up, which consists of both a vegetation index system and a climate index systeln. The former includes a forest cover percentage index and a crop yield index; the later does three variable indexes of wind speed, air temperature and humidity. An integrated regional ecological benefit index.was developed through combinations of some coined evaluation indexes from the evaluation system.And to take Zhaozhou County and Anda County as a case study, the regional ecological benetits since establishment of windbreak systems of the two counties were evaluated dynamically using the integrated index. 展开更多
关键词 Windbreak system regional ecological benefit INDEX EVALUATION
在线阅读 下载PDF
Review of trans-Mediterranean power grid interconnection:a regional roadmap towards energy sector decarbonization 被引量:1
14
作者 Kaifeng Yu Paul van Son 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期115-126,共12页
Climate change is becoming an important issue in all fields of infrastructure development.Electricity plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern.A well-built trans-... Climate change is becoming an important issue in all fields of infrastructure development.Electricity plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern.A well-built trans-Mediterranean backbone grid can hedge the profound evolution of regional power generation,transmission,and consumption.To date,only Turkey and the Maghreb countries(i.e.,Morocco,Algeria,and Tunisia)are connected with the Continental European Synchronous Area.Other south-and east-shore countries have insufficient interconnection infrastructures and synchronization difficulties that have proven to be major hurdles to the implementation of large-scale solar and wind projects and achievement of climate goals.This study analyzes the current trans-boundary grid interconnections and power and carbon emission portfolios in the Mediterranean region.To align with the recently launched new climate target‘Fit for 55’program and the accelerated large-scale renewables target,a holistic review of projected trans-Mediterranean grids and their market,technical,and financial obstacles of implementation was conducted.For south-and east-shore countries,major legal and regulatory barriers encompassing non-liberalized market structure,regulation gaps of taxation and transmission tariffs,and the private sector’s access rights need to be removed.Enhancement of domestic grids,substations,and harmonized grid codes and frequency,voltage,and communication technology standards among all trans-Mediterranean countries are physical prerequisites for implementing the Trans-Mediterranean Electricity Market.In addition,the mobilization of capital instruments along with private and international investments is indispensable for the realization of supranational transmission projects.As the final section of the decarbonization roadmap,the development of electric appliances,equipment,and vehicles with higher efficiency is inevitable in the decarbonized building,transportation,and industry sectors. 展开更多
关键词 Mediterranean Grid interconnection regional roadmap Power system Decarbonization Climate change
在线阅读 下载PDF
Impact of adolescent complex regional pain syndrome on the psychopathology of young men ahead of military service: A retrospective cohort analysis of Korean conscription data 被引量:1
15
作者 Shin-Heon Lee Myeong-Jin Ko +2 位作者 Taek-Kyun Nam Jeong-Taik Kwon Yong-Sook Park 《Military Medical Research》 SCIE CSCD 2021年第3期363-372,共10页
Background: The relationship between physical and psychopathological features in complex regional pain syndrome(CRPS) has been a subject of constant interest, but no data are available in adolescents. Therefore, we ai... Background: The relationship between physical and psychopathological features in complex regional pain syndrome(CRPS) has been a subject of constant interest, but no data are available in adolescents. Therefore, we aimed to identify the factors associated with psychopathology in adolescents with CRPS ahead of military service.Methods: We retrospectively reviewed all conscription examinees who had completed a Military Personality Inventory(MPI) during a period between February 2013 and December 2016. A total of 63 persons with a history of CRPS(19-years of age for all) were enrolled. Basic demographic and pain-related data were analyzed to examine their association with MPI results. The mean FGR score as well as the 8 subdomain scores were compared between those with pain duration at <15 months(n=30) vs. ≥15 months(n=33). Binary MPI results(normal-abnormal) were also compared between the two groups.Results: In multivariate analysis, abnormal MPI was associated with pain duration, with an odds ratio(OR) at 1.05 for every 1-month increase [95% confidence interval(CI) 1.02–1.08;P=0.002]. Subjects with pain duration at ≥15 months have lower faking good response score(P<0.001 vs. those with pain duration at <15 months), and higher abnormal MPI result rate, faking bad response, inconsistency, anxiety, depression, somatization, paranoid, personality disorder cluster A, and personality disorder cluster B scores(P<0.05). Pain duration was significantly associated with the MPI variables.Conclusions: Pain duration is associated with psychopathology in adolescents with CRPS. Psychopathologic features increased as the disease duration increased. A comprehensive understanding of time-dependent psychopathological factors could support the planning of multimodal approaches for managing adolescent CRPS. 展开更多
关键词 Chronic pain Complex regional pain syndromes PSYCHOPATHOLOGY Personality inventory ADOLESCENT Military personnel
在线阅读 下载PDF
Procedural simulation:medical student preference and value of three task trainers for ultrasound guided regional anesthesia 被引量:2
16
作者 Shadi Lahham Taylaur Smith +6 位作者 Jessa Baker Amanda Purdy Erica Frumin Bret Winners Sean P.Wilson Abdulatif Gari John C.Fox 《World Journal of Emergency Medicine》 CAS 2017年第4期287-291,共5页
BACKGROUND: Ultrasound guided regional anesthesia is widely taught using task trainer models. Commercially available models are often used; however, they can be cost prohibitive. Therefore, alternative "homemade&... BACKGROUND: Ultrasound guided regional anesthesia is widely taught using task trainer models. Commercially available models are often used; however, they can be cost prohibitive. Therefore, alternative "homemade" models with similar fidelity are often used. We hypothesize that professional task trainers will be preferred over homemade models. The purpose of this study is to determine realism, durability and cleanliness of three different task trainers for ultrasound guided nerve blocks.METHODS: This was a prospective observational study using a convenience sample of medical student participants in an ultrasound guided nerve block training session on January 24 th, 2015. Participants were asked to perform simulated nerve blocks on three different task trainers including, 1 commercial and 2 homemade. A questionnaire was then given to all participants to rate their experiences both with and without the knowledge on the cost of the simulator device.RESULTS: Data was collected from 25 participants. The Blue Phantom model was found to have the highest fidelity. Initially, 10(40%) of the participants preferred the Blue Phantom model, while 10(40%) preferred the homemade gelatin model and 5(20%) preferred the homemade tofu model. After cost awareness, the majority, 18(72%) preferred the gelatin model.CONCLUSION: The Blue Phantom model was thought to have the highest fidelity, but after cost consideration the homemade gelatin model was preferred. 展开更多
关键词 Ultrasound guided NERVE block TASK TRAINER regional ANESTHESIA
在线阅读 下载PDF
Probe into Key Techniques of Regional-Oriented 3D GIS 被引量:2
17
作者 ZHULiang-feng WUXin-cai PANXin 《Journal of China University of Mining and Technology》 2005年第2期141-147,共7页
Regional Geological Information System combines the multi-dimensional and dynamic spatial information into an integrated spatial information system. 3D geological modeling and its preprocessing or post-processing are ... Regional Geological Information System combines the multi-dimensional and dynamic spatial information into an integrated spatial information system. 3D geological modeling and its preprocessing or post-processing are the most difficult problems for constructing the system. Based on the current 3D GIS technique, some basic problems in establishing the system are discussed in this paper, including 3D spatial data model, 3D geological modeling, and visu- alization of 3D geological data. A kind of 3D vector data model based on boundary representation for geological object and its topology was developed in order to model and visualize complex geological structures. In addition, some key techniques are pointed out for further study. 展开更多
关键词 regional Geological Information System 3D GIS data model 3D geology modeling VISUALIZATION
在线阅读 下载PDF
New Regional Satellite Positioning Constellation Scheme Discussion 被引量:1
18
作者 初海彬 张乃通 顾学迈 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期471-476,共6页
The characteristics of present “Beidou” satellite positioning system are analyzed. In order to perfect our country regional satellite positioning system, the idea of “Beidou” geosychronous earth orbit (GEO) sate... The characteristics of present “Beidou” satellite positioning system are analyzed. In order to perfect our country regional satellite positioning system, the idea of “Beidou” geosychronous earth orbit (GEO) satellites combined with some middle earth orbit (MEO) satellites constellation is put forward. The details of general satellite constellation optimized method are described, using this method the multiple positioning constellation design results are gained. And those results belong to two type of sehems, one is 2 GEO plus some MEO satellites and the other is 3 GEO plus some MEO satellites. Through simulation and comparison, among those multiple design results, final optimized regional positioning constellation is given. In order to check the chosen constellation cover performance, the position dilution of preeision(PDOP) is calculated, and with ,satellite constellation simulation software Satlab many coverage performances of the chosen constellation substellar point track, elevation, azimuth and visible satellites number changing situation are also simulated. 展开更多
关键词 satellite navigation “Beidou” system position dilution of precision (PDOP) regional coverage
在线阅读 下载PDF
LMI Approach to Robust H_∞/H_2 Controller Design with Regional Poles Constraint of a Pump-Motor System 被引量:1
19
作者 郭初生 王向周 王渝 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期57-61,共5页
The time domain guideposts requirements of a pump-motor system is transfered into a series of constraints which express the robust performance upper bound and regional poles limits of the closed loop system. Then the ... The time domain guideposts requirements of a pump-motor system is transfered into a series of constraints which express the robust performance upper bound and regional poles limits of the closed loop system. Then the servo system control problem is transferred into the problem of robust performance optimizing under regional poles constrains described by linear matrix inequality (LMI). These LMIs are easy to solve through the Matlab LMI-toolbox. Simulations indicate that the controller has excellent dynamic, static and disturbance rejection performance, and the control system is robust and has perfect H2 performance to the bounded external torque disturbance. 展开更多
关键词 linear matrix inequality (LMI) H∞/H2 robust control regional poles placement pump-motor system servo system
在线阅读 下载PDF
Postmortem regional distribution of morphine in dependent rats 被引量:1
20
作者 王惠玲 马丽霞 +1 位作者 唐承汉 赵晏 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第4期230-234,共5页
Objective: Morphine concentration measured in postmortem tissues may or may not reflect antemortem concentration. We measured levels of morphine in autopsied tissues to determine whether morphine distribution in morph... Objective: Morphine concentration measured in postmortem tissues may or may not reflect antemortem concentration. We measured levels of morphine in autopsied tissues to determine whether morphine distribution in morphine-dependent rats is altered after death. Methods: Solid-phase extraction was used to extract morphine from the samples, and morphine levels were measured at 0-96 h postmortem using gas chromatography. Results: The study of the morphine dependent rats showed a significant (P<0.05) increase of morphine concentration in postmortem cardiac blood, liver tissues and kidneys tissues. A significant increase was also observed at 72 h and 96 h postmortem in the brain, while morphine levels in cardiac tissues only increased at 24 h and 96 h postmortem. These changes were associated with an observed pH rapid decrease: pH of cardiac blood dropped from 7.36±0.15 to 6.86±0.09 (P<0.01), pH of liver tissues from 6.98±0.04 to 6.34±0.03 (P<0.05). Conclusion: The postmortem regional distribution of morphine occurs in dependent rats, but different from the change that occurs in acute poisoning rats. The morphine concentration in cardiac blood and tissues tends to increase during the period of 0-96 h postmortem in dependent rats. Morphine concentration increases with pH rapid decrease. The antemortem internal amount of morphine affects its postmortem regional distribution. It appears that several mechanisms are accountable for postmortem morphine distribution. The understanding of the mechanisms and patterns may eventually lead to better choices of samples which may better represent antemortem drug levels. 展开更多
关键词 postmortem regional distribution DEPENDENCE MORPHINE RAT
在线阅读 下载PDF
上一页 1 2 18 下一页 到第
使用帮助 返回顶部