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Interpreting the Shortwave Infrared &Thermal Infrared Regions of Remote Sensed Electromagnetic Spectrum with Application for Mineral-Deposits Exploration
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作者 Yu-Jun Zhang Fo-Jun Yao 《Journal of Applied Mathematics and Physics》 2015年第2期254-261,共8页
The ASTER (Advanced Space-borne Thermal Emission and Reflection radiometer) data, including all the 3 parts: VNIR (Visible and Near-Infrared), SWIR (Short Wave Infrared), TIR (Thermal Infrared), were applied for extra... The ASTER (Advanced Space-borne Thermal Emission and Reflection radiometer) data, including all the 3 parts: VNIR (Visible and Near-Infrared), SWIR (Short Wave Infrared), TIR (Thermal Infrared), were applied for extraction of mineral deposits, such as the Ni-Cu deposit in eastern Tianshan, the gypsum in western Tianshan, and the borax in Tibetan. This paper discusses the extraction methodology using the ASTER remote sensing data and reveals the good extraction results. This paper bravely represents the summary of the main achievement for this field by the scientists in other countries and gives a comparison with the works by others. The new achievements, described in this paper, comprise the extraction of anomalies for Ni-Cu deposit, gypsum, and borax. 展开更多
关键词 SWIR (Short Wave Infrared) TIR (Thermal Infrared) RS (Remote Sensing) ETM (Enhanced THEMATIC Mapper) ASTER (Advanced Space-Borne THERMAL Emission and Reflection Radiometer) EMR (Electromagnetic Radiation) SAM (Spectral Angle Mapper)
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Cellular Perception: When the Cell Model Includes a Sense Order which Ensues from a Philosophy of Nature, the Signaling and Epigenetics Effects which Can Result from Exposure to Magnetic Fields Are Described Better 被引量:2
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作者 Pierre Le Chapellier Badri Matta 《Neuroscience & Medicine》 2011年第3期161-177,共17页
Academic biology-medicine refers to a couple of philosophies, Organicism and Mechanism, which translates into an association of Cybernetic diagrams and molecular Reductionism. This association presents logical difficu... Academic biology-medicine refers to a couple of philosophies, Organicism and Mechanism, which translates into an association of Cybernetic diagrams and molecular Reductionism. This association presents logical difficulties which make it unsuitable to describe correctly biological effects of electromagnetic fields, EMF. But these logical difficulties may be overcome when renewing the organic cell idea by means of a Philosophy of Nature which juxtaposes causality order and sense order in the cell. The signalsome, the set of descriptive components resulting from the genome, is constantly reorganized. This remodeling may become epigenetic when the phenotype becomes transformed by experience of perceptions in a given medium, because the perception of overall information coming from the extracellular medium becomes functional within the system. In that cellular perception, it is stated that the significance base which contributes to the sense order results from the qualitative topological structure of the extracellular medium. Therefore the EMF interactions target is not only the membrane and its molecules;it is also the structure of the extracellular medium which bathes the membrane. Knowing that the sense order modulation constitutes the global soil of the (localized) causality order, it is possible to obtain a same EMF bioeffect on a membrane molecule by treating a culture of cells in its bath or by treating only the extracellular aqueous medium. Consequently, the double bioeffect resulting from EMF exposure is described simply, because the sense order, such as it results from the qualitative structuring of the medium, forms the significance base which directs the causal mechanics of the cellular answer. 展开更多
关键词 Philosophy of Nature APORIA ORGANICISM sense Order Causal Order Cell EPIGENETICS Static Magnetic FIELDS SMF Electromagnetic FIELDS EMF Topological Thermodynamics Extracellular Aqueous Medium
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Uniformly Bounded Set-Valued Composition Operators in the Spaces of Functions of Bounded Variation in the Sense of Riesz
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作者 Wadie Aziz Nelson Merentes 《International Journal of Modern Nonlinear Theory and Application》 2015年第4期226-233,共8页
We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty ... We show that the lateral regularizations of the generator of any uniformly bounded set-valued composition Nemytskij operator acting in the spaces of functions of bounded variation in the sense of Riesz, with nonempty bounded closed and convex values, are an affine function. 展开更多
关键词 j-Variation in the sense of RIESZ SET-VALUED Functions Left and Right Regularizations UNIFORMLY BOUNDED OPERATOR Composition (Nemytskij) OPERATOR Jensen Equation
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珠江口淇澳岛红树林湿地变化及调控对策研究 被引量:50
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作者 王树功 黎夏 +2 位作者 周永章 刘凯 陈桂珠 《湿地科学》 CSCD 2005年第1期13-20,共8页
对珠江口内伶仃洋淇澳岛红树林湿地的变化及其驱动力进行了分析。采用的方法包括收集部分历史资料、三个时相段红树林的遥感图像监测和实地样方调查。根据 2 0 0 4年最新遥感测算 ,大约有 2 0 0hm2 红树林生长在该岛 ,这些红树林是珠江... 对珠江口内伶仃洋淇澳岛红树林湿地的变化及其驱动力进行了分析。采用的方法包括收集部分历史资料、三个时相段红树林的遥感图像监测和实地样方调查。根据 2 0 0 4年最新遥感测算 ,大约有 2 0 0hm2 红树林生长在该岛 ,这些红树林是珠江口重要的生态系统 ,但已受到强烈人为干扰。在过去近 2 0年里 ,约 77hm2 的天然红树林被毁掉 ,用于水产养殖、城镇基础设施建设。近些年来研究区红树林面积不断增加 ,尤其是自 1999年实行红树林人工恢复工程以来 ,新引种的红树林 (无瓣海桑Sonneratiaapetala)得以重建。但是淇澳岛红树林斑块的空间格局和种的构成发生了变化 ,红树林群落植物多样性明显减弱。在综合分析基础上 ,根据生态系统管理的思想 ,提出了以构建典型的红树林生态序列和红树林湿地植被多样性为目标的淇澳岛红树林湿地生态系统恢复和建设的建议。 展开更多
关键词 湿 湿 2004 1999
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The Comparison of Diagnostic Significance of Narrow Band Imaging in Contrast of White Light Endoscopy in the Assessment of Nasopharyngeal Cancer 被引量:1
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作者 Paudel Sharad Zhichun Huang +3 位作者 Xin Yang Wu Cao Ghimire Pratiksha Kharbuja Naresh 《Journal of Cancer Therapy》 2020年第3期160-171,共12页
Background: Narrow band imaging (NBI) is reported to improve the diagnostic importance of nasopharyngeal cancer. The purpose of this review was to evaluate the diagnostic significance of NBI in the literature and comp... Background: Narrow band imaging (NBI) is reported to improve the diagnostic importance of nasopharyngeal cancer. The purpose of this review was to evaluate the diagnostic significance of NBI in the literature and compare it to the conventional white light endoscopy. The use of narrow band imaging (NBI) and further technological achievements concerning the resolution and magnification of endoscopic images have in the past 15 years. With the use of NBI, superficial mucosal lesions, which may be missed by standard WLI endoscopy, can be identified easily by their neoangiogenic pattern. Objective:?To assess diagnostic value of the narrow band imaging and white light endoscopy in nasopharyngeal carcinoma and compare diagnostic values (sensitivity, specificity, positive predictive value and negative predictive value) with white light endoscopy. Search Methods: From 2010 to 2020, data was searched from electronic databases such as PubMed, web of science. We used narrow band imaging as a key word accordance with diagnostic modalities such as sensitivity, specificity, PPV and NPV and data were collected. Results: We have found mainly 6 studies have discussed about diagnostic value of endoscopy in nasopharyngeal carcinoma in the total of 2746 suspected patients. Among them, 5 studies have compared diagnostic values such as sensitivity, specificity, positive predictive value and negative predictive value between NBI and WLE. Among 5 studies, 4 studies have found higher sensitivity in NBI, 2 studies found higher 1 equal to WLE specificity in NBI. 3 studies have compared PPV and NPV between NBI and WLE. Among them, all the studies found higher PPV and NPV in NBI than WLE. Conclusion: Recently?developed narrow band imaging has a great significance in the diagnosis of nasopharyngeal carcinoma. Although NBI has also encountered some problem such as contact bleeding and darker image. So, further evaluation should be done. 展开更多
关键词 narrow Band Imaging White Light ENDOSCOPY Head and NECK NEOPLASMS NASOPHARYNGEAL Carcinoma NBI Classification IPCLs Image Enhanced ENDOSCOPY
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Endoscopic tools for the diagnosis and evaluation of celiac disease 被引量:5
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作者 Gianluca Ianiro Antonio Gasbarrini Giovanni Cammarota 《World Journal of Gastroenterology》 SCIE CAS 2013年第46期8562-8570,共9页
Celiac disease(CD)is an autoimmune disease of the small bowel induced by ingestion of wheat,rye and barley.Current guidelines indicate histological analysis on at least four duodenal biopsies as the only way to diagno... Celiac disease(CD)is an autoimmune disease of the small bowel induced by ingestion of wheat,rye and barley.Current guidelines indicate histological analysis on at least four duodenal biopsies as the only way to diagnose CD.These indications are based on the conception of the inability of standard endoscopy to make diagnosis of CD and/or to drive biopsy sampling.Over the last years,technology development of endoscopic devices has greatly ameliorated the accuracy of macroscopic evaluation of duodenal villous pattern,increasing the diagnostic power of endoscopy of CD.The aim of this paper is to review the new endoscopic tools and procedures proved to be useful in the diagnosis of CD,such as chromoendoscopy,Fujinon Intelligent Chromo Endoscopy,Narrow Band Imaging,Optical Coherence Tomography,Water-Immersion Technique,confocal laser endomicroscopy,high-resolution magnification endoscopy,capsule endoscopy and I-Scan technology. 展开更多
关键词 CELIAC disease MALABSORPTION syndrome DUODENUM Diagnostic techniques and proceduresEndoscopy CHROMOENDOSCOPY Fujinon intelligent chromo ENDOSCOPY narrow band imaging Optical coherence tomography Water-immersion technique Confocal laser ENDOMICROSCOPY High-resolution mag-nification ENDOSCOPY Capsule ENDOSCOPY I-scan tech-nology
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Effective use of the Japan Narrow Band Imaging Expert Team classification based on diagnostic performance and confidence level 被引量:6
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作者 Daizen Hirata Hiroshi Kashida +4 位作者 Mineo Iwatate Tomomasa Tochio Akira Teramoto Yasushi Sano Masatoshi Kudo 《World Journal of Clinical Cases》 SCIE 2019年第18期2658-2665,共8页
Five years have passed since the Japan Narrow Band Imaging Expert Team (JNET) classification was proposed in 2014. However, the diagnostic performance of this classification has not yet been established. We conducted ... Five years have passed since the Japan Narrow Band Imaging Expert Team (JNET) classification was proposed in 2014. However, the diagnostic performance of this classification has not yet been established. We conducted a retrospective study and a systematic search of Medical Literature Analysis and Retrieval System On-Line. There were three retrospective single center studies about the diagnostic performance of this classification. In order to clarify this issue, we reviewed our study and three previous studies. This review revealed the diagnostic performance in regards to three important differentiations.(1) Neoplasia from non-neoplasia;(2) malignant neoplasia from benign neoplasia;and (3) deep submucosal invasive cancer (D-SMC) from other neoplasia. The sensitivity in differentiating neoplasia from non-neoplasia was 98.1%-99.8%. The specificity in differentiating malignant neoplasia from benign neoplasia was 84.7%-98.2% and the specificity in the differentiation D-SMC from other neoplasia was 99.8%-100.0%. This classification would enable endoscopists to identify almost all neoplasia, to appropriately determine whether to perform en bloc resection or not, and to avoid unnecessary surgery. This article is the first review about the diagnostic performance of the JNET classification. Previous reports about the diagnostic performance have all been retrospective single center studies. A large-scale prospective multicenter evaluation study is awaited for the validation. 展开更多
关键词 JAPAN narrow Band IMAGING EXPERT TEAM CLASSIFICATION Magnifying endoscopy narrow-BAND IMAGING Validation Diagnostic performance Colonoscopy Colorectal neoplasms
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QPSK DS-CDMA System over Rayleigh Channel with a Randomly-Varying Frequency Narrow-Band Interference: Frequency Tracking Analysis
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作者 Aloys N. Mvuma 《Wireless Sensor Network》 2010年第3期243-249,共7页
This paper analyses frequency tracking characteristics of a complex-coefficient adaptive infinite-impulse response (IIR) notch filter used for suppression of narrow-band interference (NBI) with a randomly-varying freq... This paper analyses frequency tracking characteristics of a complex-coefficient adaptive infinite-impulse response (IIR) notch filter used for suppression of narrow-band interference (NBI) with a randomly-varying frequency in a quadriphase shift keying (QPSK) modulated direct-sequence code-division multiple-access (DS-CDMA) communication system. The QPSK DS-CDMA signals are transmitted over a frequency non-selective Rayleigh fading channel. The analysis is based on a first-order real-coefficient difference equation with respect to steady-state instantaneous frequency tracking error from which a closed-form expression that relates frequency tracking mean square error (MSE) with number of DS-CDMA active users and NBI power is obtained. Closed-form expressions for optimum notch bandwidth coefficient and step size constant that minimize the frequency tracking MSE are also derived. Computer simulations are included to substantiate the accuracy of the analyses. 展开更多
关键词 CODE-DIVISION Multiple Access (CDMA) Quadriphase Shift Keying (QPSK) Complex Adaptive IIR Notch Filter narrow-BAND Interference (NBI) FREQUENCY Tracking MSE
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Effects of a Traditional Japanese Medicine Goshajinkigan, Tokishigyakukagoshuyushokyoto on the Warm and Cold Sense Threshold and Peripheral Blood Flow 被引量:1
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作者 Rika Tsukada Takuji Yamaguchi +3 位作者 Liu Hang Masako Iseki Hiroyuki Kobayashi Eiichi Inada 《Health》 2014年第8期757-763,共7页
The purpose of this study was to investigate the effects of a traditional Japanese medicine Goshajinkigan (TJ-107) and Tokishigyakukagoshuyushokyoto (TJ-38) on warm sense threshold, cold sense threshold and the periph... The purpose of this study was to investigate the effects of a traditional Japanese medicine Goshajinkigan (TJ-107) and Tokishigyakukagoshuyushokyoto (TJ-38) on warm sense threshold, cold sense threshold and the peripheral blood flow. 31 healthy volunteers (control group: 9people, TJ-107 group: 12 people, TJ-38group:10 people) were examined. Drugs administered 2.5 g a dose. Analysis was before and after 1 hour dosage. The warm and cold sense threshold in the thenar of the non-handedness site of these subjects was measured using a thermostimulator (Intercross-200, Intercross Co., Tokyo, Japan). The peripheral blood flow in the finger of the non-handedness site of these subjects was measured using a full-field laser perfusion imager (FLPI, Moor Instruments Ltd., England). Control: The vehicle had no significant effect on the warm sense threshold, cold sense threshold and the peripheral blood flow. TJ-107: The warm sense threshold and cold sense threshold were significantly decreased, and the reaction latency of cold sense was significantly shortening. The peripheral blood flow was significantly increased second and third finger at 115.6%, 119.3%, respectively. TJ-38: The cold sense threshold and the reaction latency of cold sense were significantly increased. The peripheral blood flow was significantly increased second and third finger with 114.3%, 112.8%, respectively. These results suggest that TJ-107 and TJ-38 have effects on the changed warm sense threshold, cold sense threshold and increased peripheral blood flow. 展开更多
关键词 A Traditional JAPANESE MEDICINE Goshajinkigan Tokishigyakukagoshuyushokyoto The WARM and Cold sense THRESHOLD PERIPHERAL Blood Flow
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Spatial Pattern of Land Cover Change Using Remotely Sensed Imagery and GIS: A Case Study of Omo-Shasha-Oluwa Forest Reserve, SW Nigeria (1986-2002) 被引量:1
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作者 Oludare H. Adedeji Clement O. Adeofun 《Journal of Geographic Information System》 2014年第4期375-385,共11页
Spatial patterns of land cover changes in the Omo-Shasha-Oluwa Forest Reserves were conducted on Landsat TM and ETM+ imageries of 1986 and 2002 using remote sensing and GIS techniques. Extent of tree plantation (Gmeli... Spatial patterns of land cover changes in the Omo-Shasha-Oluwa Forest Reserves were conducted on Landsat TM and ETM+ imageries of 1986 and 2002 using remote sensing and GIS techniques. Extent of tree plantation (Gmelina arborea) grew from about 145 sq. km in 1986 to about 322 sq. km in 2002 (122% increase). The natural forest declined from about 2569 sq. km in 1986 to about 2253 sq. km by 2002, while the non-forest areas increased by some 5% from 341 km2?in 1986 to about 490 km2?by 2002. Land cover pattern and its changes in the study area are linked to both natural and anthropogenic processes such as illegal logging, demand for soft wood for industries and expansion of settlements. The conversion of natural forest into monoculture plantations should be discouraged because they do not give room for biodiversity. Specific forestry and environmental laws and regulations that significantly address landscape changes in reserved and protected areas should be enforced to reduce activities that negatively affect the forest reserves. There is also the need to develop a wider and more integrated GIS system of the forest and other land resources in the country to assist different kinds of planning and management activities. 展开更多
关键词 Classification Land COVER CHANGE Change-Detection GIS Landsat TM and ETM%PLUS% Remote Sensing Omo-Shasha-Oluwa Forest RESERVE
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Reverse genetics: Unlocking the secrets of negative sense RNA viral pathogens 被引量:1
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作者 Kathryn Edenborough Glenn A Marsh 《World Journal of Clinical Infectious Diseases》 2014年第4期16-26,共11页
Negative-sense RNA viruses comprise several zoonotic pathogens that mutate rapidly and frequently emerge in people including Influenza, Ebola, Rabies, Hendra and Nipah viruses. Acute respiratory distress syndrome, enc... Negative-sense RNA viruses comprise several zoonotic pathogens that mutate rapidly and frequently emerge in people including Influenza, Ebola, Rabies, Hendra and Nipah viruses. Acute respiratory distress syndrome, encephalitis and vasculitis are common disease outcomes in people as a result of pathogenic viral infection, and are also associated with high case fatality rates. Viral spread from exposure sites to systemic tissues and organs is mediated by virulence factors, including viral attachment glycoproteins and accessory proteins, and their contribution to infection and disease have been delineated by reverse genetics; a molecular approach that enables researchers to experimentally produce recombinant and reassortant viruses from cloned cD NA. Through reverse genetics we have developed a deeper understanding of virulence factors key to disease causation thereby enabling development of targeted antiviral therapies and well-defined live attenuated vaccines. Despite the value of reverse genetics for virulence factor discovery, classical reverse genetic approaches may not provide sufficient resolution for characterization of heterogeneous viral populations, because current techniques recover clonal virus, representing a consensus sequence. In this review the contribution of reverse genetics to virulence factor characterization is outlined, while the limitation of the technique is discussed withreference to new technologies that may be utilized to improve reverse genetic approaches. 展开更多
关键词 Reverse genetics Viral pathogen NEGATIVE sense RNA viruses Influenza A VIRUS EBOLA VIRUS RABIES VIRUS Hendra VIRUS Nipah VIRUS
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基于无导词义消歧的语义查询扩展 被引量:4
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作者 王瑞琴 孔繁胜 《情报学报》 CSSCI 北大核心 2011年第2期131-137,共7页
一个构造良好的查询是信息检索质量的基本保证,语义查询扩展技术解决了传统信息检索系统不能很好理解用户查询意图的问题,在提高检索查全率的同时保证了检索准确率.本文以查询关键字之间的语义关联为切入点,辅以隐式反馈技术获取消歧上... 一个构造良好的查询是信息检索质量的基本保证,语义查询扩展技术解决了传统信息检索系统不能很好理解用户查询意图的问题,在提高检索查全率的同时保证了检索准确率.本文以查询关键字之间的语义关联为切入点,辅以隐式反馈技术获取消歧上下文,以WordNet本体库和WordNet Domains扩展库作为消歧数据源,使用基于局部上下文和基于图论的两类无导词义消歧方法进行查询关键字到本体概念的映射,最后基于概念词汇关联完成基于语义的查询扩展.综合WordNet本体库和WordNet Domains扩展库中的各项知识源对查询词义进行判定,保证了词义消歧的精度;采用无导词义消歧实现查询词义的快速判定,保证了信息检索的实时性;根据查询关键词的多寡分别提出两类消歧方法,满足了各种查询需求. 展开更多
关键词 Word sense DISAMBIGUATION Based Query Expansion WordNet
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Development of Magnetic Compound Fluid Rubber Sensor for Practical Usage on &gamma;-Irradiation and Energy Harvesting for Broad-Band Electromagnetic Waves 被引量:1
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作者 Kunio Shimada Ryo Ikeda +1 位作者 Hiroshige Kikura Hideharu Takahashi 《World Journal of Mechanics》 2019年第9期205-231,共27页
We have performed sequential studies on new types of soft rubber for their application as artificial skin in robots and haptic sensors. Based on a proposed electrolytic polymerization method and novel adhesion techniq... We have performed sequential studies on new types of soft rubber for their application as artificial skin in robots and haptic sensors. Based on a proposed electrolytic polymerization method and novel adhesion technique for rubber and a metal that utilizes a metal complex hydrate, we have developed an MCF rubber sensor. This sensor uses a magnetic compound fluid (MCF), natural rubber (NR-latex) or chloroprene rubber latex (CR-latex), and requires the application of a magnetic field. The potential application of the developed sensor in various engineering scenarios and our daily lives is significant. In this regard, we investigated the effects of &gamma;-irradiation, infrared radiation, microwaves, and a thermal source on the MCF rubber sensor. We established that the MCF rubber is effective enough to be used for power generation of broadband electro-magnetic waves from &gamma;-rays to microwaves, including the range of the solar spectrum, which is the typical characteristic obtained in the present investigation. The remarkable attribute is that the MCF rubber sensor dose is not degraded by &gamma;-irradiation. We also demonstrated the effectiveness of the MCF rubber sensor in energy harvesting. 展开更多
关键词 Γ-IRRADIATION Photovoltaics Energy Harvesting Mechanical Property Thermal Source Infrared Rays Electromagnetic Waves Induced Voltage Natural RUBBER CHLOROPRENE RUBBER Adhesion Electrolytic Polymerization MAGNETIC Cluster MAGNETIC Field MAGNETIC COMPOUND FLUID (MCF) Sensing Robot
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Characteristics of Male Family Caregivers in Japan and Their Sense of Care Burden, Capacity to Deal with Stress, and Subjective Sense of Well-Being
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作者 Sayoko Uemura Keiko Sekido Tetsuya Tanioka 《Health》 2014年第18期2444-2452,共9页
This study aimed to clarify the characteristics of Japanese male family caregivers in terms of their sense of care burden, their capacity to deal with stress, and their subjective sense of well-being. A survey consist... This study aimed to clarify the characteristics of Japanese male family caregivers in terms of their sense of care burden, their capacity to deal with stress, and their subjective sense of well-being. A survey consisting of questionnaires and interviews was conducted from March to May 2014 in the subjects’ homes. Subjects were 27 Japanese males (the age range: 54 - 85) who provided home care for their family member. Caregivers who were good at relieving stress or who had a subjective sense of well-being were found to have a low care burden. The types and seriousness of diseases of the care recipients were not related to the caregivers’ sense of burden, capacity to deal with stress, or subjective sense of well-being. Based on the interview results, caregivers were found to have the following characteristics: they were particular about methods of care;they learned how to provide home care by themselves;they used their social intelligence in home care;they always provided home care while keeping the future in mind;and most notably, they considered home care to be their primary occupation. On the whole, male caregivers were found to alleviate the burdens of home care by making use of the nursing-care service systems that enabled them to relieve stress and enjoy their leisure time. Caregivers considered home care to be their occupation and used their past social experiences. The workforce helped them deal with the care recipients’ health conditions or day-to-day changes so that they could overcome the care burden. 展开更多
关键词 MALE Family Home Caregivers sense of Care BURDEN Capacity to DEAL with Stress SUBJECTIVE sense of WELL-BEING
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吉林省露水河地区森林景观格局变化 被引量:11
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作者 于德永 王艳艳 +4 位作者 郝占庆 潘耀忠 李京 龙中华 李月臣 《资源科学》 CSSCI CSCD 北大核心 2005年第4期147-153,共7页
遥感影像记录的地物信息具有很大的时空延展性,20世纪80年代中期以前传统林业政策在吉林省露水河地区非常盛行,森林经营以采伐为主,从20世纪90年代初开始当地林业经营策略渐趋科学,本文选用研究区1985年及1999年两期遥感影像从景观、类... 遥感影像记录的地物信息具有很大的时空延展性,20世纪80年代中期以前传统林业政策在吉林省露水河地区非常盛行,森林经营以采伐为主,从20世纪90年代初开始当地林业经营策略渐趋科学,本文选用研究区1985年及1999年两期遥感影像从景观、类型及斑块3个尺度研究其森林景观格局和斑块变化特征,结果表明:研究区森林景观本底由成熟林转变为中龄针叶林和成熟阔叶林,成熟针叶林受到的破坏最为严重,全区森林景观趋向破碎化,除中龄针叶林外,其它森林景观类型平均斑块变小。区域森林景观要素有部分趋于优化,如森林覆盖率提高了6·37%,中龄针叶林景观类型逐渐占优势,有利于恢复区域地带性植被,大量宜林地绿化成林等。造成这种格局的主要原因是人类对森林产品的采伐,森林群落自身的演替也是造成区域森林景观破碎化的重要因素,但其影响作用较人类活动小,气候变化因素对森林景观变化起促进作用。本文对研究区森林景观格局优化提出了建议。 展开更多
关键词 2080 2090 1999 1985
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长江三峡库区地质灾害遥感图像信息处理及其监测和评估 被引量:30
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作者 杨武年 濮国梁 +2 位作者 CAUNEAU F RANCHIN T PARIS J P 《地质学报》 EI CAS CSCD 北大核心 2005年第3期423-430,i005-i006,共10页
长江三峡作为世界上最大的水利工程,引起了世界的广泛关注。水库堤岸的长度、水库容载力、三峡移民数量以及其对生态环境的影响都成为议论的焦点。最引人注目的是长江两岸存在大量的地质灾害,如:滑坡、崩塌等,其中有些大型灾害体目前仍... 长江三峡作为世界上最大的水利工程,引起了世界的广泛关注。水库堤岸的长度、水库容载力、三峡移民数量以及其对生态环境的影响都成为议论的焦点。最引人注目的是长江两岸存在大量的地质灾害,如:滑坡、崩塌等,其中有些大型灾害体目前仍处于活动状态,这将给三峡工程的安全与库岸稳定性以及库区生态环境带来深远的影响。因此,采用3S和多时相TM、SPOT、ERS-SAR和RADARSAT等图像集成新技术来快速有效地监测、研究和评估地质灾害对三峡工程以及周边环境的影响,为地质灾害的预防和治理提供科学依据,本成果具有重要的学术意义和实用价值。 展开更多
关键词 RADARSAT SPOT SAR ERS 3S
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基于遥感信息的华北冬小麦区域生长模型及模拟研究 被引量:50
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作者 马玉平 王石立 +3 位作者 张黎 侯英雨 庄立伟 王馥棠 《气象学报》 CAS CSCD 北大核心 2005年第2期204-215,共12页
卫星遥感估产和作物生长模拟在作物监测和产量预测方面有各自不可替代的优势。但是,遥感估产难以揭示作物生长发育和产量形成的内在机理,作物模拟在区域应用时初始值的获取和参数的区域化遇到很多困难。如何利用二者的互补性使其相互结... 卫星遥感估产和作物生长模拟在作物监测和产量预测方面有各自不可替代的优势。但是,遥感估产难以揭示作物生长发育和产量形成的内在机理,作物模拟在区域应用时初始值的获取和参数的区域化遇到很多困难。如何利用二者的互补性使其相互结合受到人们关注。该文在Wofost模型本地化和区域化的基础上,首次利用同化法的思路探讨了MODIS遥感信息与华北冬小麦生长模拟模型结合的可行性和方法,初步建立了潜在生产水平(水分适宜条件)下区域遥感-作物模拟框架模型(WSPFRS模型)。模拟结果显示:WSPFRS模型对区域尺度的出苗期重新初始化后,模拟的开花期、成熟期空间分布的准确性比Wofost模拟结果有所改进;利用遥感信息对区域尺度上返青期生物量重新初始化后,模拟贮存器官干重的空间分布更接近实际单产的分布,贮存器官干重的高值区与实际高产区基本相符。该研究将为下一步实际水分供应条件下基于遥感信息的冬小麦区域生长模拟研究奠定了基础。 展开更多
关键词 MODIS
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近20年来淇澳岛红树林湿地景观格局分析 被引量:33
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作者 王树功 黎夏 +2 位作者 刘凯 周永章 陈桂珠 《地理与地理信息科学》 CSSCI CSCD 北大核心 2005年第2期53-57,共5页
该文分析近20a来淇澳岛红树林湿地景观格局演变,采用遥感和GIS相结合的方法,利用遥感图像处理软件ERDAS对3个时相(1988年、1995年、2002年)的LandsatTM遥感图像应用专家系统方法分类;结合ARCGIS8 1,辅助FRAGSTATS3 01景观软件计算斑块... 该文分析近20a来淇澳岛红树林湿地景观格局演变,采用遥感和GIS相结合的方法,利用遥感图像处理软件ERDAS对3个时相(1988年、1995年、2002年)的LandsatTM遥感图像应用专家系统方法分类;结合ARCGIS8 1,辅助FRAGSTATS3 01景观软件计算斑块和类型水平上的景观格局指数。淇澳岛红树林面积呈上升趋势,1988年、1995年和2002年分别为20 16hm2、28 08hm2、57 96hm2;斑块数目从1988年的1个增加到2002年的18个,总斑块密度、平均斑块周长面积比呈上升趋势;平均斑块大小、平均斑块分维数、平均斑块形状指数呈下降趋势。近20a来淇澳岛红树林湿地景观受人为干扰,景观破碎化程度不断扩大,需对湿地多功能景观进行科学调控。 展开更多
关键词 湿 1988 2002 Landsat 1995 ERDAS TM 湿 20a
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遥感傅里叶变换红外光谱测定气体污染物在单光程上的浓度分布 被引量:2
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作者 李燕 王连军 王俊德 《分析化学》 SCIE EI CAS CSCD 北大核心 2005年第6期825-827,共3页
采用开路傅里叶变换红外光谱(OPFTIR),对室内固定点源排放的污染物丙酮进行了实时遥感监测。给出了丙酮在同一条光路上,不同光程长的积分浓度和采用多项式拟合出的积分浓度,并且利用一种一维计算机层析算法(CT)模型,分别用高斯模型和多... 采用开路傅里叶变换红外光谱(OPFTIR),对室内固定点源排放的污染物丙酮进行了实时遥感监测。给出了丙酮在同一条光路上,不同光程长的积分浓度和采用多项式拟合出的积分浓度,并且利用一种一维计算机层析算法(CT)模型,分别用高斯模型和多项式模型,重构出了丙酮在所测光路上的浓度分布曲线。两种方法重构出丙酮在所测光路上,浓度的最大值分别为0.0190mg/L和0.0213mg/L,最大值分别位于坐标3.11m和3.09m处。研究结果表明两种方法对浓度的分布能够得到较为一致的结果。可见,OPFTIR与一维CT模型联用,可以给出污染物的单光程浓度分布,该技术应用于工业或环境卫生监测,具有预警作用。 展开更多
关键词 线 T
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食管癌内支架术后再梗阻的内镜治疗
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作者 王曼彤 王宏光 徐小华 《中国厂矿医学》 2005年第2期100-100,共1页
目的探讨食管癌内支架术后形成再梗阻内镜治疗的方法和意义。方法通过内镜用高频电热探头烧除网管中心内壁增生的癌组织,直至管腔再通,半月后复查,烧灼后网管内径缩小者用探条扩张。结果9例病人接受高频电烧治疗总次数58次,平均7.1次/... 目的探讨食管癌内支架术后形成再梗阻内镜治疗的方法和意义。方法通过内镜用高频电热探头烧除网管中心内壁增生的癌组织,直至管腔再通,半月后复查,烧灼后网管内径缩小者用探条扩张。结果9例病人接受高频电烧治疗总次数58次,平均7.1次/例。每次形成再梗阻时间29d,电烧治疗间隔时间23d,5例接受探条治疗总次数13次。所有病人均因癌症晚期全身衰竭而终止治疗。结论食管支架扩张术能迅速使食管良恶性狭窄扩张再通,但部分食管癌再通后形成继发性癌性再梗阻。用高频电烧及食管探条张器可达到梗阻再通,由于癌组织生长迅速,梗阻形成时间短,需经常电烧及扩张,使食管癌晚期患者能进流食或半流食,提高部分生活质量。 展开更多
关键词
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