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area的相关文献在1985年到2023年内共计39138846篇,主要集中在肿瘤学、自动化技术、计算机技术、无线电电子学、电信技术 等领域,其中期刊论文649篇、会议论文1篇、专利文献39138196篇;相关期刊269种,包括地学前缘、中国科学、中国科学等; 相关会议1种,包括中国电机工程学会第五届青年学术会议等;area的相关文献由50000位作者贡献,包括不公告发明人、王伟、张伟等。

area—发文量

期刊论文>

论文:649 占比:0.00%

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论文:1 占比:0.00%

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论文:39138196 占比:100.00%

总计:39138846篇

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area

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    • Carla Carvalho-Luis; JoséManuel Rodrigues; Luís M.Martins
    • 摘要: After the first detection of the gram-negative bacterium,Xylella fastidiosa multiplex in Portugal,in January 2019,a“Demarcated Area”was delimited and an“Action Plan”to control the pathogen has been developed.It is considered one of the greatest threats to plant health worldwide and leads to loss of forests vitality and productivity.The current study was developed till June 2020,with the objective to understand the dimension of the issue worldwide and in Portugal,analyzing the state-of-the-art on the biology,dispersion,symptoms,control and risks associated with this bacterium(Research Phase).In the Prospecting Phase,we collected 5 branches with 5-8 leaves,from the four quadrants of the tree,wrapping and labeling them-so 2,261 samples were collected and sent to the laboratory for analysis.It was possible to determine that the two initial outbreaks were not an isolated case,as 107 additional outbreaks were detected in other places,revealing a much more worrying panorama,requiring further analysis on the real impact of this bacterial strain on the natural environment.By the end of this study the demarcated area covered about 62,000 ha.The most affected species was lavender with 30%of positive outbreaks,followed by gorse with 22%,and rosemary with 11%.Spread of Phillaenus spumarius and X.fastidiosa indicates that insect vector and transport links appear to be dispersal facilitators together with Douro River.As eradication is unfeasible to achieve in the coming years,containment will be the most appropriate strategy.
    • 刘帛松
    • 摘要: 当下,LPWAN的发展已经走到了一个转折点,原有市场驱动力的优势或许已"山穷水尽",要想"柳暗花明",企业必须将更多的注意力聚焦在LPWAN的应用上。经过5年的快速发展,LPWAN(Low-Power Wide-Area Network,低功率广域网络)如今正面临转折,其原有的驱动优势已然不再。今后,企业必须将注意力集中在LPWAN应用上,才能在下个阶段的发展中夺得先机。
    • Alcindo Neckel; Laércio Stolfo Maculan; Letícia Muller; Dominiki Ceolin; Julia Cristina Clivatti; Paloma Toscan; Lisiane Zwirtes; Henrique Aniceto Kujawa
    • 摘要: The analysis of satellite images is of fundamental importance in relation to understanding the evolution in land use.The general objective of this study is to analyze the changes in characteristics of rural land use in the municipality of Carazinho(RS)from 2001 to 2020 through the analysis of images taken from the Landsat TM-7 and TM-8 satellites.The TM-7 and TM-8 satellite images were classified and supervised,thus generation thematic maps with the following groups:tillage,forest,water resources and exposed soil.The analysis of this study showed that in 2001 the tillage group had an area of 10,651.6 ha,the forest group had an area of 7,248.03 ha,the water resources group occupied an area of 1,444.96 ha,and the exposed soil group occupied an area of 6,798.75 ha.When using the images taken in 2020,the same area presented the following data:the tillage group with an area of 15,941.5 ha.(60.95%),the forest group with an area of 4,320.99 ha(16.52%),water resources group with an area of 141.02 ha(0.53%),and the exposed soil group with an area of 5,747.22 ha(21.97%).The results demonstrate changes in land use during the study period,mainly with regard to the increase of cultivation areas and,consequently,the suppression of vegetation.
    • Lyhour Hin; Borarin Buntong; Manuel RReyes; Lyda Hok; Lytour Lor; Horace Clemmons; Ted SKornecki
    • 摘要: Vegetables are vital for human health and are consumed five days a week in Cambodia.However,the production cannot meet domestic demands due to labor-intensive farming and production costs related to soil tillage.Mechanization is needed along with soil quality and sustainability improvements by the adoption of CA(Conservation Agriculture).The research aimed to compare the performance of the no-till vegetable transplanter with punch-planter in CA and hand transplanting in CT(Conventional Tillage).The study was conducted at the Royal University of Agriculture,Cambodia,starting from January to September 2020,by firstly growing sunn hemp as a cover crop and then transplanting Thai round eggplant.A randomized complete block design was used with three treatments,replicated three times.Each plot was 2 m by 15 m,with 0.2-m row spacing.The results showed that the transplanter speed was 0.54 kmh^-1,almost two times the speed of punch planter and 9 times the speed of hand transplanting.The highest working capacity was also achieved with the transplanter.However,different transplanting did not affect plant spacing,or plant density.Plant spacing was 1 m,and plant density varied from 10,300 to 11,500 plantsha-1.Plant growth and yield were also not influenced by the transplanter in CA,or hand transplanting in CT.Average fruit diameter,fruit weight,fruit number,and yield were 38 mm,31.4 gfruit-1,15.7 fruitsplant-1 and 3.9 tha-1,respectively.The maximum working area of the transplanter and its break-even area were 25.2 ha·y^-1 and 18.3 ha·y^-1,respectively.Using the no-till transplanter may save both time and labor,but its use in combination with CA was unlikely to affect plant growth and yield in the short term.
    • JIA Wenbin; LI Yongsheng; MI Kuifeng; YU Xiaofei
    • 摘要: Objective The Altyn Tagh marks the northern margin of the Qinghai-Tibet Plateau and lies between the Tarim block to the north and the Qaidam block,Qilian Orogen,and Kunlun orogenic belt to the south.The Altyn Tagh region contains ophiolite,high-to ultrahigh-pressure metamorphic rocks,and igneous rocks.Previous research has virified the occurrence of continental rifting,subduction,slab roll-back,and collision between the Tarim block and Proto-Tethys oceanic plate.Moreover,Kaladaban volcanic rocks are mainly distributed in the north Altyn region.Studies of the magmatic evolution of this region have proposed that Altyn oceanic plate was subducted during the Ordovician(Han et al.,2012;Wang et al.,2017).However,the specific timing and other aspects of the subduction are debated,and an investigation of granite porphyry in the Kaladaban area would improve our understanding of this subduction event.In this study,we present new U-Pb zircon dating result and Sr-Nd isotope composition data for granite porphyry from the North Altyn region.The objective is to constrain the timing of subduction of the North Altyn oceanic plate and establish the petrogenesis and magma source of the granite porphyry.
    • GONG Daxing; HUI Bo; DAI Zongming; LAI Yang; TIAN Enyuan
    • 摘要: Objective A set of REE-rich clay rocks is formed at the top of the Emeishan basalt in the eastern Yunnan-Western Guizhou area,accompanied by Nb,Zr,Ga.It is a new type of REE deposit and has great resource potential.This paper introduces its metallogenic conditions and element occurrence states,discusses the genetic mechanism.
    • 摘要: 自从Alienware 1996年创立以来,宗旨就是提供最强的PC性能,最有个性的设计和最好的服务。每一款Alienware产品的出现,都会成为玩家心中的经典乃至信仰,传承优秀的Alienware Area 51m R2并没有沉浸在过去的成功上,搭载桌面10核i9、满血版的RTX2080S等规格的配备,再一次让世人看到顶配笔记本向极限性能发起的新一轮冲击!
    • Ehsan ABDI; Hamid R SALEH; Baris MAJNONIAN; Azade DELJOUEI
    • 摘要: Vegetation roots contribute to soil fixation and reinforcement, thus improving soil resistance against erosion. Generally, the amount of soil fixation presented by roots mainly depends on root density and tensile strength. In the present study, we conducted the research in order to further understand the biotechnical properties of Haloxylon persicum and also to quantify its role in increasing soil cohesion in arid lands of Iran. Ten H. persicum shrubs were randomly selected for root distribution and strength investigations, in which five samples were set on flat terrain and other five samples on a moderate slope terrain. The profile trench method was used to assess the root area ratio(RAR) as the index of root density and distribution. Two profiles were dug around each sample, up and downslope for sloped treatment and north and south sides for flat treatment. The results showed that RAR increased with increasing soil depth and significantly decreased in 40–50 cm layers of downhill(0.320%) and 50–60 cm for uphill(0.210%). The minimum values for the northward and southward profiles were 0.003% and 0.003%, respectively, while the maximum values were 0.260% and 0.040%, respectively. The relationship between the diameter of root samples and root tensile strength followed a negative power function, but tensile force increased with increasing root diameter following a positive power function. The pattern of increased cohesion changes in soil profile was relatively similar to RAR curves. The maximum increased cohesion due to the presence of roots in uphill and downhill sides were 0.470 and 1.400 kPa, respectively. In the flat treatment, the maximum increased cohesions were 0.570 and 0.610 kPa in northward and southward profiles, respectively. The analysis of variance showed that wind and slope induced stresses did not have any significant effect on the amount of increased cohesion of H. persicum. The findings served to develop knowledge about biotechnical properties of H. persicum root system that can assist in assessing the efficiency of afforestation and restoration measures for erosion control in arid lands.
    • Fredrick ANDrew Attah; Christianah Mopelola Asaleye; Adeleye Dorcas Omisore; Babatope Ayodeji Kolawole; Adeniyi Sunday Aderibigbe; Mathew Alo
    • 摘要: BACKGROUND Neuropathy is a common complication of diabetes mellitus resulting from direct damage by hyperglycemia to the nerves and/or ischemia by microvascular injury to the endoneurial vessels which supply the nerves. Median nerve is one of the peripheral nerves commonly affected in diabetic neuropathy. The median nerve size has been studied in non-Nigerian diabetic populations. In attempt to contribute to existing literature, a study in a Nigerian population is needed.AIM To evaluate the cross-sectional area(CSA) of the median nerve using B-mode ultrasonography(USS) and the presence of peripheral neuropathy(PN) in a cohort of adult diabetic Nigerians.METHODS Demographic and anthropometric data of 85 adult diabetes mellitus(DM) and 85 age-and sex-matched apparently healthy control(HC) subjects were taken. A complete physical examination was performed on all study subjects to determine the presence of PN and modified Michigan Neuropathy Screening Instrument(MNSI) was used to grade its severity. Venous blood was taken from the study subjects for fasting lipid profile(FLP), fasting blood glucose(FBG) and glycated haemoglobin(HbA1 c) while their MN CSA was evaluated at a point 5 cm proximal to(5 cmCATL) and at the carpal tunnel(CATL) by high-resolution Bmode USS. Data was analysed using SPSS version 22.RESULTS The mean MN CSA was significantly thicker in DM subjects compared to the HC at 5 cmCATL(P 0.05). However, the severity of DPN had no additional effect on MN CSA 5 cm proximal to and at the CATL. There was no significant association between MN CSA and duration of DM and glycemic control.CONCLUSION Thickening of the MN CSA at 5 cmCATL and CATL is seen in DM. Presence of DPN is associated with worse thickening of the MN CSA at the CATL but not at5 cmCATL. Severity of DPN, duration of DM, and glycemic control had no additional effect on the MN CSA.
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