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Challenges and opportunities in remote sensing-based crop monitoring: a review

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National Science Review 2023年第4期10卷 203-219页

作者： Bingfang Wu Miao Zhang Hongwei Zeng Fuyou Tian Andries B Potgieter Xingli Qin Nana Yan Sheng Chang Yan Zhao Qinghan Dong vijendra boken Dmitry Plotnikov Huadong Guo Fangming Wu Hang Zhao Bart Deronde Laurent Tits Evgeny Loupian State Key Laboratory of Remote Sensing Science Aerospace Information Research Institute Chinese Academy of Sciences School of Resources and Environment University of Chinese Academy of Sciences Executive Committee of Group on Earth Observations Global Agricultural Monitoring (GEOGLAM) Queensland Alliance for Agriculture and Food Innovation The University of Queensland Department of Remote Sensing Flemish Institute of Technological Research Department of Geography and Earth Science University of Nebraska-Kearney Department of Satellite Monitoring Technologies Space Research Institute of Russian Academy of Sciences

Building a more resilient food system for sustainable development and reducing uncertainty in global food markets both require concurrent and near-real-time and reliable crop information for decision ***-driven crop monitoring has become a main method to derive crop information at local, regional,and global scales by revealing the spatial and temporal dimensions of crop growth status and ***, there is a lack of quantitative, objective, and robust methods to ensure the reliability of crop information, which reduces the applicability of crop monitoring and leads to uncertain and undesirable consequences. In this paper, we review recent progress in crop monitoring and identify the challenges and opportunities in future efforts. We find that satellite-derived metrics do not fully capture determinants of crop production and do not quantitatively interpret crop growth status; the later can be advanced by integrating effective satellite-derived metrics and new onboard sensors. We have identified that ground data accessibility and the negative effects of knowledge-based analyses are two essential issues in crop monitoring that reduce the applicability of crop monitoring for decisions on food security. Crowdsourcing is one solution to overcome the restrictions of ground-truth data accessibility. We argue that user participation in the complete process of crop monitoring could improve the reliability of crop *** users to obtain crop information from multiple sources could prevent unconscious ***, there is a need to avoid conflicts of interest in publishing publicly available crop information.

关键词： crop monitoring crop condition crop production Ground data Remote Sensing

Uncertainties in assessing the effect of climate change on agriculture using model simulation and uncertainty processing methods

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Chinese Science Bulletin 2011年第8期56卷 729-737页

作者： YAO FengMei QIN PengCheng ZHANG JiaHua LIN ErDa boken vijendra College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100094 China Chinese Academy of Meteorological Sciences Beijing 100081 China School of Geoscience Yangtze University Jingzhou 434025 China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Geography and Earth Science University of Nebraska at Kearney Kearney NE 68849 USA

Model simulation is an important way to study the effects of climate change on *** assessment is subject to a range of uncertainties because of either incomplete knowledge or model technical uncertainties,impeding effective decision-making to climate *** the basis of uncertainties in the impact assessment at different levels,this article systematically summarizes the sources and propagation of uncertainty in the assessment of the effect of climate change on agriculture in terms of the climate projection,the assessment process,and the crop models linking to climate ***,techniques and methods focusing on different levels and sources of uncertainty and uncertainty propagation are introduced,and shortcomings and insufficiencies in uncertainty processing are pointed ***,in terms of how to accurately assess the effect of climate change on agriculture,improvements to further decrease potential uncertainty are suggested.

关键词：不确定性模型影响评估气候变化农业影响模型模拟不确定性传播气候预测气候模型

基于模型模拟气候变化对农业影响评估的不确定性及处理方法

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科学通报 2011年第8期56卷 547-555页

作者：姚凤梅秦鹏程张佳华林而达 boken vijendra 中国科学院研究生院地球科学学院北京100049 中国气象科学研究院北京100081 长江大学地球科学学院荆州434023 中国农业科学院环境与可持续发展研究所北京100081 Department of Geography and Earth Science University of Nebraska at Kearney

模型模拟是研究气候波动对作物影响的重要手段,也是评估未来气候变化对农业可能影响的主要途径.由于科学认识和模拟技术上的不确定性,当前的气候变化对农业潜在影响评估结果一致性很差,为农业应对气候变化的决策制定带来了极大困难.基... 详细信息

模型模拟是研究气候波动对作物影响的重要手段,也是评估未来气候变化对农业可能影响的主要途径.由于科学认识和模拟技术上的不确定性,当前的气候变化对农业潜在影响评估结果一致性很差,为农业应对气候变化的决策制定带来了极大困难.基于不同层次的影响评估中不确定性,本文从气候预估、影响评估建模过程及气候模式与作物模型的连接3个方面,系统总结了气候变化对农业影响评估中不确定性的来源及传播过程;并介绍了针对多层次、多样化的不确定性源及不确定性传播的处理技术与方法,指出了当前不确定性处理中的缺陷与不足.最后对如何准确地实施气候变化对农业影响的评估,进一步减小气候变化对农业影响评估潜在的不确定性也提出了改进的建议.

关键词：气候变化农业影响评估不确定性模型模拟

Closed-form solution for shock wave propagation in density-graded cellular material under impact

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Theoretical & Applied Mechanics Letters 2021年第5期11卷 252-259页

作者： vijendra Gupta Addis Kidane Michael Sutton Department of Mechanical Engineering University of South Carolina300 Main StreetColumbiaSC 29208USA

Density-graded cellular materials have tremendous potential in structural applications where impact resistance is *** materials subjected to high impact loading result in a compaction type deformation,usually modeled using continuum-based shock *** resulting governing differential equation of the shock model is nonlinear,and the density gradient further complicates the *** studies have employed numerical methods to obtain the *** this study,an analytical closed-form solution is proposed to predict the response of density-graded cellular materials subjected to a rigid body *** for the velocity of the impinging rigid body mass,energy absorption capacity of the cellular material,and the incident stress are obtained for a single shock *** results obtained are in excellent agreement with the existing numerical solutions found in the *** proposed analytical solution can be potentially used for parametric studies and for effectively designing graded structures to mitigate impact.

关键词： Functionally graded cellular material Analytical modeling Impact response Closed-form solution Energy absorption Density gradient

A therapeutic potentiality and toxicity concern of nutrient plant Annona squamosa Linn.

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Traditional Medicine Research 2024年第3期9卷 52-65页

作者： Manisha Chandrakar Khomendra Kumar Sarwa vijendra Kumar Suryawanshi Kumari Pramila University College of Pharmacy Raipur Chhattisgarh Swami Vivekanand Technical University BhilaiChhattisgarh 492001India Department of Pharmacy Government Girls PolytechnicRaipurChhattisgarh 492001India Bharti College of Pharmacy Bharti UniversityDurgChhattisgarh 491001India Faculty of Pharmacy M J College BhilaiDurgChhattisgarh 490023India

Annona squamosa *** is famous for its nutritional value with a long history of medicinal benefits due to the presence of many phytochemicals,including alkaloids,diterpenes,essential oil,phytopeptides,*** studies envisaged that Annona squamosa possesses cytotoxic,diuretic,antiurolithiatic,antitumor,anti-psoriatic,antioxidant,and hepatoprotective *** plant is traditionally used for the treatment of wound infection,dysentery,seizure,tumors,fever,vomiting,parasitic infections,hypertension,thyroid,toothache,acne,heart disease,inflammation,diabetes,hair loss,dandruff,hemorrhage,maggot-infected sores,abortifacient,and ***,some chemical constituents isolated from the plant have shown specific toxic effects in human and animal models,such as acute oral toxic effects,genotoxic,neurotoxic,and ocular *** plant has diverse pharmacological actions,the seeds of this plant possess a genotoxic effect but on the contrary,the bark of the plant shows genoprotective activity.A large number of ethnobotanical studies reported the seed of this plant is used to induce abortion in humans,but a scientific study carried out in pregnant rats reported aqueous seed extract of the plant did not interfere with reproductive *** presented review summarized the traditional uses,pharmacological,and toxicological activities of the isolated compounds from this ***,some patents and commercial products related to Annona squamosa are also brought up in this article to explore its application which would attract the scientific community to search out its hidden side.

关键词： Annona squamosa cytotoxicity cancer abortifacient genotoxicity isosquamocin annonacin neurotoxicity ocular toxicity

All ileo-cecal ulcers are not Crohn's:Changing perspectives of symptomatic ileocecal ulcers

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World Journal of Gastrointestinal Endoscopy 2017年第7期9卷 327-333页

作者： Jay Toshniwal Romesh Chawlani Amit Thawrani Rajesh Sharma Anil Arora Hardik L Kotecha Mohan Goyal vijendra Kirnake Pankaj Jain Pankaj Tyagi Naresh Bansal Munish Sachdeva Piyush Ranjan Mandhir Kumar Praveen Sharma Vikas Singla Rinkesh Bansal Vineet Shah Sunita Bhalla Ashish Kumar Department of Gastroenterology Dr.Toshniwal’s Gastro-Liver Care Department of Gastroenterology Sir Gangaram Hospital Department of Histo-pathology Sir Gangaram Hospital

To investigated clinical, endoscopic and histopathological parameters of the patients presenting with ileocecal ulcers on colonoscopy. METHODSConsecutive symptomatic patients undergoing colonoscopy, and diagnosed to have ulcerations in the ileocecal (I/C) region, were enrolled. Biopsy was obtained and their clinical presentation and outcome were recorded. RESULTSOut of 1632 colonoscopies, 104 patients had ulcerations in the I/C region and were included in the study. Their median age was 44.5 years and 59% were males. The predominant presentation was lower GI bleed (55, 53%), pain abdomen ± diarrhea (36, 35%), fever (32, 31%), and diarrhea alone (9, 9%). On colonoscopy, terminal ileum was entered in 96 (92%) cases. The distribution of ulcers was as follows: Ileum alone 40% (38/96), cecum alone 33% (32/96), and both ileum plus cecum 27% (26/96). The ulcers were multiple in 98% and in 34% there were additional ulcers elsewhere in colon. Based on clinical presentation and investigations, the etiology of ulcers was classified into infective causes (43%) and non-infective causes (57%). Fourteen patients (13%) were diagnosed to have Crohn’s disease (CD). CONCLUSIONNon-specific ileocecal ulcers are most common ulcers seen in ileo-cecal region. And if all infections are clubbed together then infection is the most common (> 40%) cause of ulcerations of the I/C region. Cecal involvement and fever are important clues to infective cause. On the contrary CD account for only 13% cases as a cause of ileo-cecalulcers. So all symptomatic patients with I/C ulcers on colonoscopy are not Crohn’s.

关键词： Ileocecal Crohn’s disease Diffuse large B-cell non-hodgkin’s lymphoma