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上博楚竹书(二)《民之父母》“夙夜基命宥密”考
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作者 黎广基 《中国文字研究》 2005年第1期59-65,共7页
本文对上海博物馆楚竹书《民之父母》中的"夙夜基命宥密"进行了考辨,主张:"基命"谓周人始受之天命,"密"应释"宓","宥密"应读为"有服"。"夙夜基命有服",犹言日... 本文对上海博物馆楚竹书《民之父母》中的"夙夜基命宥密"进行了考辨,主张:"基命"谓周人始受之天命,"密"应释"宓","宥密"应读为"有服"。"夙夜基命有服",犹言日夜服行上天之基命。 展开更多
关键词 楚竹书 夙夜基命宥密
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袁崇焕与北京保卫战
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作者 阎崇年 《学习与研究(北京)》 1981年第2期43-44,共2页
明朝末年杰出的军事家袁崇焕,在抵御八旗军南犯的北京保卫战中,立下了丰功伟勋。他虽不幸蒙冤而死,但其英雄业绩却值得称颂。袁崇焕(1584—1630年),字元素,号自如,广西藤县(祖籍广东东莞)人。他自幼读书勤奋,聪颖机敏,万历四十七年(1619... 明朝末年杰出的军事家袁崇焕,在抵御八旗军南犯的北京保卫战中,立下了丰功伟勋。他虽不幸蒙冤而死,但其英雄业绩却值得称颂。袁崇焕(1584—1630年),字元素,号自如,广西藤县(祖籍广东东莞)人。他自幼读书勤奋,聪颖机敏,万历四十七年(1619年)中进士。旋任福建邵武知县。袁崇焕登上政治舞台时。 展开更多
关键词 袁崇焕 北京保卫战 登上政治舞台 崇祯帝 宁远大捷 东林党 蒙古骑兵 祖大寿 基命 阿巴泰
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《詩》簡讀札三則
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作者 陳晨 《简帛》 2022年第2期93-102,共10页
安大簡《詩經·碩鼠》簡81“遆皮樂=或=”“遆皮樂=土=”、簡82“遆皮樂=蒿=”中的重文符號皆應從《毛詩》讀三遍,這是《詩經》類文獻中獨有的一種重文符號的特殊用法;阜陽漢簡《詩經》簡S014“印其離”當從《毛詩》讀;上博簡《民... 安大簡《詩經·碩鼠》簡81“遆皮樂=或=”“遆皮樂=土=”、簡82“遆皮樂=蒿=”中的重文符號皆應從《毛詩》讀三遍,這是《詩經》類文獻中獨有的一種重文符號的特殊用法;阜陽漢簡《詩經》簡S014“印其離”當從《毛詩》讀;上博簡《民之父母》引《周頌·昊天有成命》“夙夜基命宥密”句應該讀爲“夙夜諆命有密”。同時,本文對《尚書·洛誥》“王若弗敢及天基命定命”中“基命”的相關訓釋問題也做了考證。 展开更多
关键词 《詩經》 重文符號 印其離 夙夜基命宥密
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Amplitude phase control for electro-hydraulic servo system based on normalized least-mean-square adaptive filtering algorithm 被引量:4
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作者 姚建均 富威 +1 位作者 胡胜海 韩俊伟 《Journal of Central South University》 SCIE EI CAS 2011年第3期755-759,共5页
The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorit... The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorithm.The command input was corrected by weights to generate the desired input for the algorithm,and the feedback was brought into the feedback correction,whose output was the weighted feedback.The weights of the normalized LMS adaptive filtering algorithm were updated on-line according to the estimation error between the desired input and the weighted feedback.Thus,the updated weights were copied to the input correction.The estimation error was forced to zero by the normalized LMS adaptive filtering algorithm such that the weighted feedback was equal to the desired input,making the feedback track the command.The above concept was used as a basis for the development of amplitude phase control.The method has good real-time performance without estimating the system model.The simulation and experiment results show that the proposed amplitude phase control can efficiently cancel the amplitude attenuation and phase delay with high precision. 展开更多
关键词 amplitude attenuation phase delay normalized least-mean-square adaptive filtering algorithm tracking performance electro- hydraulic servo system
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Probiotic bacteria change Escherichia coli-induced gene expression in cultured colonocytes:Implications in intestinal pathophysiology 被引量:10
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作者 Pinaki Panigrahi Gheorghe T Braileanu +1 位作者 Hegang Chen O Colin Stine 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第47期6370-6378,共9页
AIM: To investigate the change in eukaryotic gene expression profile in Caco-2 cells after infection with strains of Escherichia coli and commensal probiotic bacteria. METHODS: A 19 200 gene/expressed sequence tag gen... AIM: To investigate the change in eukaryotic gene expression profile in Caco-2 cells after infection with strains of Escherichia coli and commensal probiotic bacteria. METHODS: A 19 200 gene/expressed sequence tag gene chip was used to examine expression of genes after infection of Caco-2 cells with strains of normal flora E. coli,Lactobacillus plantarum,and a combination of the two. RESULTS: The cDNA microarray revealed up-regulation of 155 and down-regulation of 177 genes by E. coli . L. plantarum up-regulated 45 and down-regulated 36 genes. During mixed infection,27 genes were up-regulated and 59 were down-regulated,with nullification of stimulatory/inhibitory effects on most of the genes. Expression of several new genes was noted in this group. CONCLUSION: The commensal bacterial strains used in this study induced the expression of a large number of genes in colonocyte-like cultured cells and changed the expression of several genes involved in important cellular processes such as regulation of transcription,protein biosynthesis,metabolism,cell adhesion,ubiquitination,and apoptosis. Such changes induced by the presence of probiotic bacteria may shape the physiologic and pathologic responses they trigger in the host. 展开更多
关键词 LACTOBACILLUS Escherichia coli Gene expression Probiotic cDNA microarray
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A quantitative method for sustainable product development 被引量:1
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作者 Arash Hosseinpour 彭庆金 顾佩华 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期87-93,共7页
A quantitative measure-based method for the design and evaluation of sustainable products is proposed. The method uses multi-criteria in product design to meet sustainable requirements from qualitative criteria to qua... A quantitative measure-based method for the design and evaluation of sustainable products is proposed. The method uses multi-criteria in product design to meet sustainable requirements from qualitative criteria to quantitative metrics. The method integrates quality function deployment concepts with the life cycle assessment to establish a quantitative method for sustainable product development. It considers both customer needs and sustainable requirements by mapping these needs into design details using the axiomatic design and benchmarking methods. The method is applied in the wheelchair design. Four popular wheelchairs in the market are selected as benchmarks and are rated based on customer needs and sustainable criteria. The design matrix identifies the relationship of functional requirements and design parameters of the wheelchair. Compared to the best benchmark product, the proposed wheelchair can reduce costs by 13.8%, environment footprints 18.55%, mass 4.5%, and components 2.2%. 展开更多
关键词 SUSTAINABILITY product design life cycleassessment BENCHMARKING
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Structural evolution of Pt‐based oxygen reduction reaction electrocatalysts 被引量:5
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作者 Jiaheng Peng Peng Tao +3 位作者 Chengyi Song Wen Shang Tao Deng Jianbo Wu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第1期47-58,共12页
The commercialization of proton exchange membrane fuel cells(PEMFCs)could provide a cleaner energy society in the near future.However,the sluggish reaction kinetics and harsh conditions of the oxygen reduction reactio... The commercialization of proton exchange membrane fuel cells(PEMFCs)could provide a cleaner energy society in the near future.However,the sluggish reaction kinetics and harsh conditions of the oxygen reduction reaction affect the durability and cost of PEMFCs.Most previous reports on Pt-based electrocatalyst designs have focused more on improving their activity;however,with the commercialization of PEMFCs,durability has received increasing attention.In-depth insight into the structural evolution of Pt-based electrocatalysts throughout their lifecycle can contribute to further optimization of their activity and durability.The development of in situ electron microscopy and other in situ techniques has promoted the elucidation of the evolution mechanism.This mini review highlights recent advances in the structural evolution of Pt-based electrocatalysts.The mechanisms are adequately discussed,and some methods to inhibit or exploit the structural evolution of the catalysts are also briefly reviewed. 展开更多
关键词 Oxygen reduction reaction Structural evolution Pt‐based electrocatalyst DURABILITY In situ electron microscopy characterizations
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Preparation of Ti/PTFE-F-PbO2 Electrode with a Long Life from the Sulfamic Acid Bath and Its Application in Organic Degradation 被引量:5
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作者 洪夏萍 张蓉 +1 位作者 童少平 马淳安 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期1033-1038,共6页
A polytetrafluoroethylene (PTFE)-doped PbO2 electrode on a Ti substrate was prepared by galvanostatic method from the sulfamic acid bath (Ti/PTFE-F-PbO2-I) or nitric acid bath (Ti/PTFE-F-PbO2-II). Scanning Elect... A polytetrafluoroethylene (PTFE)-doped PbO2 electrode on a Ti substrate was prepared by galvanostatic method from the sulfamic acid bath (Ti/PTFE-F-PbO2-I) or nitric acid bath (Ti/PTFE-F-PbO2-II). Scanning Electron Microscopy revealed that the Ti/PTFE-PbO2-I electrode had a more regular morphology with smaller size crystals than the Ti/PTFE-F-PbO2-II electrode. On the basis of the results of both the accelerated electrolysis test and the empirical formula for estimating the service life of an electrode, the service life of the Ti/PTFE-PbO2-I electrode was predicted to be more than 7 years under conventional electrolysis conditions (0.1 A·cm^-2). During the treatment of 4-chlorophenol-contaminated water, the Ti/PTFE-PbO2-I anode showed both a good electro-catalytic activity and high electrochemical stability, exhibiting an excellent potential application. 展开更多
关键词 lead dioxide sulfamic acid electrochemical oxidation 4-CHLOROPHENOL
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Research on goal-setting method of rock drivage based on the balance among period, cost and quality 被引量:1
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作者 SHAN Ren-liang CAI Wei-ling +2 位作者 WANG Yu-bao LI Dong-gang CHEN Xiang 《Journal of Coal Science & Engineering(China)》 2012年第2期218-224,共7页
On the basis of the analysis on the disadvantages of the original goal-setting about rock drivage, this paper defined the "life cycle quality". With project management theory and the Cobb-Douglas function, "quality... On the basis of the analysis on the disadvantages of the original goal-setting about rock drivage, this paper defined the "life cycle quality". With project management theory and the Cobb-Douglas function, "quality-cost and quality-price curve model" and the "total cost-period prediction model" were built. Then the goal-setting method of the balance among quality, cost and period of rock drivage was constructed by finding "life cycle cost" through "life cycle quality" using "quality-cost and quality-price curve model" and ensuring period through "life cycle cost" using "total cost-period prediction model" (hereinafter referred to as the "three goals balance method"). "Value contribution" which is the value of the contribution to a mine because of rock drivage, was found in the process of constructing the "quality-cost and quality-price curve model". An industrial test was done in coal mine A with the research results, staff footage efficiency improved by 24.24%, the period shortened by 14.3%, the "life cycle cost" dropped by 2.09%, the "life cycle quality price" improved by 3.29%, and value contribution increased by 25.3%. The result shows that the new goal method setting on the basis of coal mine profit maximization can ensure construc- tion period. At the same time, it can realize cost and quality objectives and the optimization and balance of relationship among them; rewarding excavation teams by "value contribution" can combine organizational goal with personal goal, it significantly raise the employee's work efficiency. 展开更多
关键词 GOAL-SETTING life cycle theory balance among quality and cost and period value contribution
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Receptor-mediated gene delivery using polyethylenimine (PEI) coupled with polypeptides targeting FGF receptors on cells surface
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作者 LI Da WANG Qing-qing +4 位作者 TANG Gu-ping HUANG Hong-liang SHEN Fen-ping LI Jing-zhong YU Hai 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第11期906-911,共6页
Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targe... Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targeting ability. Methods: The synthetic polypeptides CR16 for binding FGF receptors was conjugated to PEI and the characters of the polypeptides in-cluding DNA condensing and particle size were determined. Enhanced efficiency and the targeting specificity of the synthesized vector were investigated in vitro and in vivo. Results: The polypeptides were successfully coupled to PEI. The new vectors PEI-CR16 could efficiently condense pDNA into particles with around 200 nm diameter. The PEI-CR16/pDNA polyplexes showed significantly greater transgene activity than PEI/pDNA in FGF receptors positive tumor cells in vitro and in vivo gene transfer, while no difference was observed in FGF receptors negative tumor cells. The enhanced transfection efficiency of PEI-CR16 could be blocked by excess free polypeptides. Conclusion: The synthesized vector could improve the efficiency of gene transfer and targeting specificity in FGF receptors positive cells. The vector had good prospect for use in cancer gene therapy. 展开更多
关键词 FGF receptors POLYETHYLENIMINE TARGETING Gene delivery Gene therapy
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Analysis of Sustainability Based on Life Cycle Assessment: An Empirical Study of Wine Production
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作者 Gabriella Arcese Maria Claudia Lucchetti Olimpia Martucci 《Journal of Environmental Science and Engineering(B)》 2012年第5期682-689,共8页
The environmental planning and the current policy initiatives in European Union are aimed at continuous improvement of the productive fabric, heading toward a system in which the "quality" of products will no longer... The environmental planning and the current policy initiatives in European Union are aimed at continuous improvement of the productive fabric, heading toward a system in which the "quality" of products will no longer regardless of their environmental impacts. In this context, the methodology of LCA (life cycle assessment) is certainly one of the most innovative methods in the field of environmental protection as it allows evaluating the environmental burdens associated with a product, process or activity by identifying and quantifying material and energy consumption and environmental emissions. The objectives focus on finding the main impacts of the wine life cycle, as well as identifying crucial activities/stages in the wine production which establish the largest impacts. This paper's objective is to expose the advantages resulting from the use of the LCA method in the wine production sector, with a specific application to wine production in the Tuscany region. 展开更多
关键词 SUSTAINABILITY LCT (life cycle thinking) approach wine production agricultural products environmental impacts.
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The Tree of Death and Eternal Life
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作者 Ken A. Bryson 《Journal of Philosophy Study》 2012年第3期145-162,共18页
The "Tree of Death" is a metaphor I use to unlock my Christian assumptions on how the dead attain eternal existence in the afterlife state. The tree's unconcealedness, in this life and presumably the next, along wi... The "Tree of Death" is a metaphor I use to unlock my Christian assumptions on how the dead attain eternal existence in the afterlife state. The tree's unconcealedness, in this life and presumably the next, along with the moral habits an agent develops in this life explain the obstinacy of the dead, that is, how the agent's irrevocable decision to side with the God of Abraham, or not, is possible. For that to be the case, the existential relationships that generate personal identity in this life must accompany (individuate) the subject in the next life. In Christian philosophy, the person-making process mirrors the relationships of the Blessed Trinity. While Martin Heidegger is not a Christian philosopher, his view on truth and being's unconcealedness provides a useful piece of the argument to continue the Thomistic case for personal immortality. Heidegger is not a catholic philosopher, but the focus he places on being's unconcealedness is consonant with the focus Thomas Aquinas puts on the intelligibility of being. While Heidegger's discussion of being is rooted in Dasein's finitude, the Thomistic interpretation of being situates unconcealedness within the perspective of God's creative act. His vision resets the possibility of applying Heidegger's fundamental ontology beyond temporality. The paper develops through a discussion of the Tree's "branches, trunk, and roots" to conclude that the Christian perspective transforms Heidegger's view of death into "the ultimate possibility of possibility." 展开更多
关键词 being's unconcealedness eternal life final decision GOD human death IMMORTALITY person-makingprocess personal identity
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Grain size based low cycle fatigue life prediction model for nickel-based superalloy 被引量:13
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作者 Peng ZHANG Qiang ZHU +2 位作者 Gang CHEN He-yong QIN Chuan-jie WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第10期2102-2106,共5页
Nickel-based superalloys are easy to produce low cycle fatigue(LCF)damage when they are subjected to high temperature and mechanical stresses.Fatigue life prediction of nickel-based superalloys is of great importance ... Nickel-based superalloys are easy to produce low cycle fatigue(LCF)damage when they are subjected to high temperature and mechanical stresses.Fatigue life prediction of nickel-based superalloys is of great importance for their reliable practical application.To investigate the effects of total strain and grain size on LCF behavior,the high temperature LCF tests were carried out for a nickel-based superalloy.The results show that the fatigue lives decreased with the increase of strain amplitude and grain size.A new LCF life prediction model was established considering the effect of grain size on fatigue life.Error analyses indicate that the prediction accuracy of the new LCF life model is higher than those of Manson-Coffin relationship and Ostergren energy method. 展开更多
关键词 nickel-based superalloy low cycle fatigue life prediction model grain size
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Service Life Prediction and Management of Concrete Bridge Structures Due to Corrosion
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作者 Moe M. S. Cheung Kevin K. L. So 《Journal of Civil Engineering and Architecture》 2015年第10期1153-1166,共14页
The increasing stocks of public infrastructure and serious deterioration of infrastructure systems due to corrosion present great financial, safety, technical and operational challenges to government organizations in ... The increasing stocks of public infrastructure and serious deterioration of infrastructure systems due to corrosion present great financial, safety, technical and operational challenges to government organizations in charge of public infrastructure development and management. To meet those challenges, a performance-based life-cycle management model for reinforced concrete structures was proposed in this paper. This model predicts the life-cycle performance of infrastructure based on the corrosion-induced deterioration mechanism: condition index as well as performance limit states. A case study is provided to demonstrate the use of the proposed performance-based life-cycle cost management model. 展开更多
关键词 Concrete structure CORROSION DETERIORATION life-cycle management.
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Approaching an Abstract Cinematic Form: The Tree of Life by Terrence Malick
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作者 Christos Dermentzopoulos Thanassis Vassiliou 《Journal of Literature and Art Studies》 2014年第9期722-728,共7页
One of the most important tools in film analysis is "segmentation", as defined by the major film theorist Christian Metz, with the help of the "great syntagmatic" (Grande Syntagmatique); an array, which will gua... One of the most important tools in film analysis is "segmentation", as defined by the major film theorist Christian Metz, with the help of the "great syntagmatic" (Grande Syntagmatique); an array, which will guarantee the classification of any kind of shot in any kind of film and its consequent decoding. The division into sections allowed a clinical approach of high validity, highlighting the hidden rhymes, the power of repetition, the underlying pulses of the film, "decoding", in a way, their soul; in essence their meaning. However, by the mid-1970s, the semiotics of cinema was considered outdated and unrealistic, mainly because it failed to solve a problem to which it was believed that it held the key to guarantee the "translation" of any abstract cinematic form. In this text, we attempt to explore what semiotics can do today and how far "segmentation" can take us in the face of a particularly "opaque" film, which is made of fragments of impressions, disparate elements and contrasts, such as The Tree of Life (2011) by Terrence Malick. 展开更多
关键词 Metz segmentation Grand Syntagmatique NARRATION EDITING
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Pressure-Dependent Base-Wavefunction Admixture and Lifetime of R1 State of La3Lu2Ga3O12:Cr3+
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作者 ZHANG Zheng-Jie MA Dong-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1147-1152,共6页
As a key factor leading to the pressure-dependent R1-line-shift reversal and R1-state lifetime, at 10 K, the pressure-dependent variation of mixing-degree of |t2^2(^3T1)e^4T2) and |t2^32E〉 base-wavefunetions in ... As a key factor leading to the pressure-dependent R1-line-shift reversal and R1-state lifetime, at 10 K, the pressure-dependent variation of mixing-degree of |t2^2(^3T1)e^4T2) and |t2^32E〉 base-wavefunetions in the wavefunction of R1 state of LLGG:Cr^3+ has been calculated and analyzed. From this, the physical origin of the pressure-dependent R1-line-shift reversal has been revealed. Furthermore, by using the pressure-dependent values of the sum of all square mixlng-coefficients of |t2^2 (^3T1)e^4T2〉 in the wavefunction of R1 state, the lifetimes of R1 state of LLG G:Cr^3+ at various pressures have been calculat, ed, which arc in good agreement with observed results. The quantum anticrossing effect between t2^32E and t2^2 (^3T1)e^4T2 levels due to both spin-orbital interaction and electron-phonon interaction is remarkable, which is related to the admixture of |t2^2(^3T1)e^4T2) and |t2^32E〉 as well as the low high crystal-field transition. 展开更多
关键词 high-pressure effect base-wavefunction mixing between |t22(3T1)e4T2〉 and |t322E〉 R1-state lifetime quantum anticrossing Ri-line-shift reversal low-high crystal-field transition
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A Packet I/O Architecture for Shell Script-based Packet Processing
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作者 Yohei Kuga Takeshi Matsuya +3 位作者 Hiroaki Hazeyama Kenjiro Cho Rodney Van Meter Osamu Nakamura 《China Communications》 SCIE CSCD 2014年第2期1-11,共11页
We propose a new scripting model for rapid and easier development of packet processing using shell scripts. In this paper we present EtherPIPE, a character network I/O device, that allows the programmer to access netw... We propose a new scripting model for rapid and easier development of packet processing using shell scripts. In this paper we present EtherPIPE, a character network I/O device, that allows the programmer to access network traffic data as a file through UNIX commands. By setting a UNIX pipe "r' from or to EtherP1PE's output or input with UNIX commands, packets can be easily processed, executing functions such as packet filtering, packet capturing, generating arbitrary packets, and rewriting header information. In order to prove the utilities of our model, we have developed FPGA-based EtherPIPE adapter using a commodity FPGA card and a character device driver featuring new offloading functions. With our prototype implementation, packet scripting works at 1Gbps wire-speed, receiving packets with precise hardware timestamps. This paper argues for use cases of the EtherPIPE, and discusses enhanced formats of character devices for easier network scripting.) 展开更多
关键词 network I/O ETHERNET Shellscript Software-Defined Networking devicedriver network adapter
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Characteristics of Antisense Non-coding RNA in the INK4 Locus and Its Roles in Disease
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作者 Jin-hua He Yu-guang Li 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第2期122-123,共2页
Abstract With the development of genome-wide sequencing technology, 195 types of functional long non-coding RNAs (lncRNAs) have so far been found, and their cellular roles are gradually being revealed. Now lncRNAs h... Abstract With the development of genome-wide sequencing technology, 195 types of functional long non-coding RNAs (lncRNAs) have so far been found, and their cellular roles are gradually being revealed. Now lncRNAs have become a hotspot in the life science. These small molecules exist in almost all higher eukaryotes, and have very important regulatory roles in these organisms. This review briefly summarizes recent progress in researches on antisense non-coding RNA in the INK4 locus. 展开更多
关键词 long non-coding RNAs antisense non-coding RNA in the INK4 locus EXPRESSION
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Thales of Miletus, Archimedes and the Solar Eclipses on the Antikythera Mechanism
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作者 G6ran Henriksson 《Journal of Earth Science and Engineering》 2014年第12期757-769,共13页
Thales of Miletus (640?-546 BC) is famous for his prediction of the total solar eclipse in 585 BC. In this paper, the author demonstrate how Thales may have used the same principle for prediction of solar eclipses ... Thales of Miletus (640?-546 BC) is famous for his prediction of the total solar eclipse in 585 BC. In this paper, the author demonstrate how Thales may have used the same principle for prediction of solar eclipses as that used on the Antikythera Mechanism. At the SEAC conference in Alexandria in 2009, the author presented the paper "Ten solar eclipses show that the Antikythera Mechanism was constructed for use on Sicily." The best defined series of exeligmos cycles started in 243 BC during the lifetime of Archimedes (287-212 BC) from Syracuse. The inscriptions on the Antikythera Mechanism were made in 100-150 BC and the last useful exeligmos started in 134 BC. The theory for the motion of the moon was from Hipparchus (ca 190-125 BC). A more complete investigation of the solar eclipses on the Antikythera Mechanism reveals that the first month in the first saros cycle started with the first new moon after the winter solstice in 542 BC. Four solar eclipses 537-528 BC, from the first saros cycle, and three one exeligmos cycle later, 487-478 BC, are preserved and may have been recorded in Croton by Pythagoras (ca 575-495 BC) and his school. 展开更多
关键词 Solar eclipse exeligmos cycle saros cycle seasonal hour equinoctial hour.
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Effect of bis(tributyltin)oxide on reproduction and population growth rate of calanoid copepod Schmackeria poplesia 被引量:1
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作者 黄瑛 朱丽岩 +1 位作者 邱旭春 张天文 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期280-287,共8页
A full life-cycle toxicity test, combined with histology, on calanoid copepod Schmackeria poplesia was used to study the effect of bis(tributyltin) oxide (TBTO). The results indicate no sex-specific differences in... A full life-cycle toxicity test, combined with histology, on calanoid copepod Schmackeria poplesia was used to study the effect of bis(tributyltin) oxide (TBTO). The results indicate no sex-specific differences in TBTO toxicity. Long-term mortalities of the copepods exposed to concentrations higher than 20 ng TBTO L"1 were significantly elevated compared with that of control, and larval development was inhibited when they were exposed to 40 and 60 ng TBTO L-1. The percentages of ovigerous females were reduced compared with the control (P〈0.01) after 24 days exposure to concentrations higher than 10 ng TBTO L-1. Histological examinations suggest that exposure to TBTO might block the posterior end of the diverticula and inhibits the production of egg sacs. A modified Euler-Lotka equation was used to calculate a population-level endpoint, the intrinsic rate of natural increase (rm), from individual life-table endpoints, i.e. mortality rate, time of release of first brood, sex ratio, the fraction of ovigerous females among all females as well as the number of nauplii per ovigerous female. Apart from the highest TBTO concentration (60 ng LI), where all females aborted their egg sacs, 20 ng TBTO L-1 was the only concentration that significantly decreased rm compared with that of control (an effect associated with decreased sex ratio). The results show that the S. poplesia is affected by prolonged exposure to low concentrations of TBTO. The full life-cycle toxicity test combined with histology experiments provides more integral understanding of the toxicity of endocrine disrupters. 展开更多
关键词 TRIBUTYLTIN REPRODUCTION population growth rate GONAD Schmackeria poplesia toxicity testing
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