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挑战与机遇:人类面临的四大困境与最大危机及其引发的科技革命 被引量:8
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作者 刘益东 《科技创新导报》 2016年第35期221-230,共10页
该文将著名的囚徒困境和自己提出来的动车困境、双刃剑困境、魔戒困境与科技危机合称"四大困境与最大危机",将其认定为目前人类面临的最大威胁和挑战,目前风起云涌的大IT革命、创客运动与科技的快速发展正全面加剧这种困境与... 该文将著名的囚徒困境和自己提出来的动车困境、双刃剑困境、魔戒困境与科技危机合称"四大困境与最大危机",将其认定为目前人类面临的最大威胁和挑战,目前风起云涌的大IT革命、创客运动与科技的快速发展正全面加剧这种困境与危机,因此将引发一场科技革命。发现目前社会已经形成了"恐怖实现系统",人类已经进入危变社会和危变时代,实现从"建设优先""产销优先"向"安全优先""解危优先"的转型是当务之急。 展开更多
关键词 动车困境 双刃剑困境 魔戒困境 致毁知识 科技危机 对不准原理 恐怖实现系统 危变社会 科技巨风险 黑客社会 最大危机 可持续创新与发展 容错战略管理 科技的总体安全观 负责任创新 图位化 科技革命
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Ground-State Phase Diagram of Transverse Spin-2 Ising Model with Longitudinal Crystal-Field 被引量:5
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作者 ZHAO Jie WEI Guo-Zhu XU Xing-Guang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期749-753,共5页
The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal-field is studied within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. The ground-state phase diagram and th... The transverse spin-2 Ising ferromagnetic model with a longitudinal crystal-field is studied within the mean-field theory based on Bogoliubov inequality for the Gibbs free energy. The ground-state phase diagram and the tricritical point are obtained in the transverse field Ω/ zJ-longitudinal crystal D / zJ field plane. We find that there are the first order-order phase transitions in a very small range of D /zJ besides the usual first order-disorder phase transitions and the second order-disorder phase transitions, 展开更多
关键词 transverse spin-2 Ising model longitudinal crystal field ground state phase diagram first orderorder phase transition
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Redox behavior and chemical species of arsenic in acidic aqueous system 被引量:11
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作者 Jin-qin YANG Li-yuan CHAI +1 位作者 Qing-zhu LI Yu-de SHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期2063-2072,共10页
Arsenic(As)removal from smelting acidic wastewater is an urgent task.The most common method is oxidation of trivalent As(III)to pentavalent As(V)subsequently precipitated by ferric(Fe(III))salts.Foundations of redox b... Arsenic(As)removal from smelting acidic wastewater is an urgent task.The most common method is oxidation of trivalent As(III)to pentavalent As(V)subsequently precipitated by ferric(Fe(III))salts.Foundations of redox behavior and chemical species are of great importance for understanding As removal.In this work,cyclic voltammetry(CV)and UV?Vis spectroscopy were used for laboratory observation;meanwhile HSC and MINTEQ software were employed for theoretical analyses.It is found that As(III)oxidation,a multiple electron transfer reaction,is diffusion-controlled.The oxidation over-potential is very high(about0.9V)in sulfuric acid solutions(pH1.0).In addition,Fe(III)?As(V)complexes are evidenced by UV?Vis spectra and chemical species analyses in series of Fe(III)?As(V)?H2SO4?H2O solutions.Therefore,the Fe(III)and As(V)species distribution against pH values are determined and a newφ?pH diagram with inclusion of Fe?As complexes is consequently compiled based on thermodynamic data predicted by other researchers. 展开更多
关键词 ARSENIC ferric-arsenic complexes φ-pH diagram chemical species acidic wastewater
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Mobile robot localization algorithm based on multi-sensor information fusion 被引量:10
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作者 WANG Ming-yi HE Li-le +1 位作者 LI Yu SUO Chao 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第2期152-160,共9页
In order to effectively reduce the uncertainty error of mobile robot localization with a single sensor and improve the accuracy and robustness of robot localization and mapping,a mobile robot localization algorithm ba... In order to effectively reduce the uncertainty error of mobile robot localization with a single sensor and improve the accuracy and robustness of robot localization and mapping,a mobile robot localization algorithm based on multi-sensor information fusion(MSIF)was proposed.In this paper,simultaneous localization and mapping(SLAM)was realized on the basis of laser Rao-Blackwellized particle filter(RBPF)-SLAM algorithm and graph-based optimization theory was used to constrain and optimize the pose estimation results of Monte Carlo localization.The feature point extraction and quadrilateral closed loop matching algorithm based on oriented FAST and rotated BRIEF(ORB)were improved aiming at the problems of generous calculation and low tracking accuracy in visual information processing by means of the three-dimensional(3D)point feature in binocular visual reconstruction environment.Factor graph model was used for the information fusion under the maximum posterior probability criterion for laser RBPF-SLAM localization and binocular visual localization.The results of simulation and experiment indicate that localization accuracy of the above-mentioned method is higher than that of traditional RBPF-SLAM algorithm and general improved algorithms,and the effectiveness and usefulness of the proposed method are verified. 展开更多
关键词 mobile robot simultaneous localization and mapping(SLAM) graph-based optimization sensor fusion
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The effect of the support on the surface composition of PtCu alloy nanocatalysts: In situ XPS and HS-LEIS studies 被引量:6
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作者 黄俊杰 宋艳英 +3 位作者 马冬冬 郑燕萍 陈明树 万惠霖 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1229-1236,共8页
Supported PtCu alloys have been broadly applied in heterogeneous catalysis and electrocatalysis owing to their excellent catalytic performance and high CO tolerance. It is important to analyze the outermost surface c... Supported PtCu alloys have been broadly applied in heterogeneous catalysis and electrocatalysis owing to their excellent catalytic performance and high CO tolerance. It is important to analyze the outermost surface composition of the supported alloy nanoparticles to understand the nature of the catalytically active sites. In this paper, homogeneous face-centered cubic PtCu nanoparticles with a narrow particle size distribution were successfully fabricated and dispersed on a high-surface-area Ti〇2 powder support. The samples were oxidized and reduced in situ and then introduced into the ultrahigh vacuum chamber to measure the topmost surface composition by high-sensitivity low-energy ion scattering spectroscopy, and to determine the oxidation states of the elements by X-ray photoelectron spectroscopy. The surface composition and morphology, elemental distribu-tion, and oxidation states of the components were found to be significantly affected by the support and treatment conditions. The PtCu is de-alloyed upon oxidation with CuO wetting on the TiO2 sur-face and re-alloyed upon reduction. Phase diagrams of the surface composition and the bulk com-position were plotted and compared for the supported and unsupported materials. 展开更多
关键词 PtCu alloy Bimetal catalyst Surface composition Phase diagram In situ XPS-LEIS
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EAG and behavioral responses of Helicoverpa armigera males to volatiles from poplar leaves and their combinations with sex pheromone 被引量:15
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作者 邓建宇 黄永平 魏洪义 《Journal of Zhejiang University Science》 EI CSCD 2004年第12期1577-1582,共6页
Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antenn... Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that some volatiles shouldmodify sex pheromone caused behavior and that some of them could possibly be used as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field. 展开更多
关键词 Helicoverpa armigera Wilted leave volatiles Chinese black poplar Sex pheromone EAG Wind-tunnel bioassay
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Blur Invariant Image Forgery Detection Method Using Local Phase Quantization
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作者 Beste Ustubioglu Elif Baykal +1 位作者 Gul Muzaffer Guzin Ulutas 《Journal of Energy and Power Engineering》 2016年第6期358-363,共6页
With the rapid development of powerful image, editing software makes the forgery of the digital image easy. Researchers proposed methods to cope with image authentication in recent years. We proposed a passive image a... With the rapid development of powerful image, editing software makes the forgery of the digital image easy. Researchers proposed methods to cope with image authentication in recent years. We proposed a passive image authentication technique to determine the copy move forgery that copied a part of an image and pasted it on the other region in the same image. First, the method divides the image into overlapping blocks. It uses LPQ (local phase quantization) to label each block. The column average value of labeled blocks constitutes the feature vector for the block. Similarity among the feature vectors gives a clue about the forgery. Local phase quantization has not been used to detect copy move forgery in the literature before. Experimental results show that, the method has higher accuracy ratios and lower false negative values under blurring operation at high levels compared to other methods. Our method can also detect multiple copy move forgery. 展开更多
关键词 Copy move forgery LPQ blur invariant.
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New tectonic map of Northern-Central-Eastern Asia: Position and evolution of Mesozoic sedimentary basins
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作者 I.Pospelov 0.Petrov +2 位作者 S.Shokalsky Li T.D. Dong S.W. 《Global Geology》 2016年第4期261-276,共16页
The beginning of the XXI century was marked a new rising of the international tectonic cartography as a result of analysis and synthesis of a huge volume of geological information obtained for the territory of Asia e... The beginning of the XXI century was marked a new rising of the international tectonic cartography as a result of analysis and synthesis of a huge volume of geological information obtained for the territory of Asia es-pecially during the last 30 years. The previous tectonic maps for Asia were created in the 1960s-1970s of the last century. Since that time, the national geological surveys have compiled tectonic maps exclusively in the limits of their own state boundaries. The international cooperation of five countries since 2002 ( Russia, China, Mongolia, Kazakhstan and Republic of Korea) gave a unique possibility to join the data into a united cartog-raphic form as Atlas of Geological Maps (since 2002-Atlas of Geological Maps of Central Asia and since 2007- Atlas of Geological Maps of Northem-Central-Eastem Asia). Both atlases include four maps: geological, tecton-ic ,metallogenic, and energy resources. Tectonic Map of Northem-Central-Eastem Asia and Adjacent Areas at scale 1 : 2 500 000 was the key map for further compilation of the metallogenic and energy resources ( coal, oil and gas) maps. By this reason, special attention was given to showing the structure and composition of the Mes-ozoic sedimentary basins in Northern-Central- Eastern Asia as the most perspective structures for oil-and-gas and coal prospect. 展开更多
关键词 tectonic map Mesozoic basins platforms and fold be lts Northern Central Eastern Asia
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Berth Management in Container Terminals: Quality of Service
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作者 Lopez-Ansorena Inigo Camarero-Orive Alberto Gonzalez-Cancelas Nicoletta Camarero-Orive Alfonso 《Journal of Shipping and Ocean Engineering》 2012年第6期340-362,共23页
This paper empirically evaluates container terminal service attributes. The methodology proposed focuses on statistical control, Based on the concept of service segmentation, the authors employed control charts to cla... This paper empirically evaluates container terminal service attributes. The methodology proposed focuses on statistical control, Based on the concept of service segmentation, the authors employed control charts to classify container terminal services. The purpose of control charts is to allow simple detection of events that are indicative of actual process change. This simple decision can be difficult where the process characteristic is continuously varying, the control chart provides statistically objective criteria of change. When change is detected and considered good its cause should be identified and possibly become the new way of working, where the change is bad then its cause should be identified and eliminated. Both theoretical and practical implications of the research findings are discussed in this paper. 展开更多
关键词 Container terminals quality of service control chart.
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Autonomous map query:robust visual localization in urban environments using Multilayer Feature Graph
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作者 李海丰 Wang Hongpeng Liu Jingtai 《High Technology Letters》 EI CAS 2015年第1期31-38,共8页
When a vehicle travels in urban areas, onboard global positioning system (GPS) signals may be obstructed by high-rise buildings and thereby cannot provide accurate positions. It is proposed to perform localization b... When a vehicle travels in urban areas, onboard global positioning system (GPS) signals may be obstructed by high-rise buildings and thereby cannot provide accurate positions. It is proposed to perform localization by registering ground images to a 2D building boundary map which is generated from aerial images. Multilayer feature graphs (MFG) is employed to model building facades from the ground images. MFG was reported in the previous work to facilitate the robot scene understand- ing in urhan areas. By constructing MFG, the 2D/3D positions of features can be obtained, inclu- cling line segments, ideal lines, and all primary vertical planes. Finally, a voting-based feature weighted localization method is developed based on MFGs and the 2D building boundary map. The proposed method has been implemented and validated in physical experiments. In the proposed ex- periments, the algorithm has achieved an overall localization accuracy of 2.2m, which is better than commercial GPS working in open environments. 展开更多
关键词 visual localization urban environment multilayer feature graph( MFG) voting- based method
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Quantification of Blur and Its Applications
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作者 Hiroyuki Hase 《Journal of Mathematics and System Science》 2012年第3期210-216,共7页
Human visual sense has two aspects in our feeling for blurred image, that is, one is the amount of blur depending on object size, the other is the amount of blur independent of the object size. In the former for examp... Human visual sense has two aspects in our feeling for blurred image, that is, one is the amount of blur depending on object size, the other is the amount of blur independent of the object size. In the former for example, when the image size becomes larger, the author feels smaller amount blur. The quantitative evaluation based on entropy for blurred images is proposed in this paper. The author calls this metric "variation entropy". This metric has two kinds of aspects that coincide with the human visual sense. The first is the absolute evaluation of blur, and the second is the relative evaluation of blur. The former can be quantified by variation entropy for a unit boundary length (or L-type variation entropy: HL ), which is dependent on resolution, and the latter can be quantified by variation entropy for a unit area (or A-type variation entropy: H^A ), which is independent of resolution. These two metrics have complementary properties. At last, two variation entropies are applied to the standard kanji character database, and then the strong relation between variation entropy and accuracy of recognition is discussed. The tendency of writing skills for grades is evaluated by applying the metric to a database collected from school children. 展开更多
关键词 Blurred image quantification of blur character database human visual sense.
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The evolution of multi-component visual signals in darters (genus Etheostoma) 被引量:1
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作者 Jennifer M. GUMM Tamra C. MENDELSON 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第2期125-139,共15页
As complex traits evolve, each component of the trait may be under different selection pressures and could respond independently to distinct evolutionary forces. We used comparative methods to examine patterns of evol... As complex traits evolve, each component of the trait may be under different selection pressures and could respond independently to distinct evolutionary forces. We used comparative methods to examine patterns of evolution in multiple components of a complex courtship signal in darters, specifically addressing the question of how nuptial coloration evolves across different areas of the body. Using spectral reflectance, we defined 4 broad color classes present on the body and fins of 17 species of freshwater fishes (genus Etheostoma) and quantified differences in hue within each color class. Ancestral state reconstruction suggests that most color traits were expressed in the most recent common ancestor of sampled species and that differences among species are mostly due to losses in coloration. The evolutionary lability of coloration varied across body regions; we found sig- nificant phylogenetic signal for orange color on the body but not for most colors on fins. Finally, patterns of color evolution and hue Of the colors were correlated among the two dorsal fins and between the anterior dorsal and anal fins, but not between any of the fins and the body. The observed patterns support the hypothesis that different components of complex signals may be subject to distinct evolutionary pressures, and suggests that the combination of behavioral displays and morphology in communication may have a strong influence on patterns of signal evolution . 展开更多
关键词 Comparative method ETHEOSTOMA Independent evolution Nuptial coloration
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