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An empirical movement model for sixgill sharks in Puget sound： Combining observed and unobserved behavior

Current Zoology 2012年第1期58卷 103-115页

作者： Levin, Phillip s. Horne, Peter Andrews, Kelly s. Williams, Greg Northwest Fisheries science Center 2725 Montlake Blvd E Seattle WA 98112 USA

Understanding the movement of animals is fundamental to population and community ecology. Historically, it has been difficult to quantify movement patterns of most fishes, but technological advances in acoustic telemetry have increased our abilities to monitor their movement. In this study, we combined small-scale active acoustic tracking with large-scale passive acoustic monitoring to develop an empirical movement model for sixgill sharks in Puget sound, WA, UsA. We began by testing whether a correlated random walk model described the daily movement of sixgills; however, the model failed to capture home-ranging behavior. We added this behavior and used the resultant model （a biased random walk model） to determine whether daily movement patterns are able to explain large-scale seasonal movement. The daily model did not explain the larger-scale pat- terns of movement observed in the passive monitoring data. In order to create the large-scale patterns, sixgills must have per- formed behaviors （large, fast directed movements） that were unobserved during small-scale active tracking. In addition, seasonal shifts in location were not captured by the dally model. We added these ＇unobserved＇ behaviors to the model and were able to capture large-scale seasonal movement of sixgill sharks over 150 days. The development of empirical models of movement al- lows researchers to develop hypotheses and test mechanisms responsible for a species movement behavior and spatial distribution. This knowledge will increase our ability to successfully manage species of concern [Current Zoology 58 （1）： 103-115, 2012].

关键词： Hexanchus griseus Movement Correlated random walk Biased random walk Displacement Movement model

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Experimental Investigations of the Three-DimensionalFlow in a Large Deflection Turbine Cascade with Tip Clearance

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Journal of Thermal science 1998年第3期7卷 149-164页

作者： M.Govardhan s.s.s.R.K.sastri V.s.Vishnubhotla ThermalurbomachinesLab DepartmentofMechanicalEngineeringIndianInstituteofTechnologyMadrasChennai600036IndiaThermalurbomachinesLabDepartmentofMechanicalEngineeringIndianInstituteofTechnologyMadrasChennai600036IndiaThermalurbomachinesLabDepartment

Results obtained from an experbontal study of the threedimensional flow survey within and exit of a large defiection linear turbine cascade are presented for a tip clearance levels of 0.08, 1.5, 3.0 percent of chord and compared with the help of boundary layer probes and that within and exit of a blade passage was done with a miniaturised five hole probe. End wall and blade tip surface static pressures were also obtained, in addition to flow visualisation studies. A strong horse-shoe vortex forms in front of the leading edge for zero clearance whereas this vortex does not appear for 3 percent clearance indicating that for large clearance the pressure forces have dominating infiuence than the viscous forces. In addition to normally known clearance vortex, a small tip separation vortex was noticed on the blade tip surface inside the tip gap. Due to the area contraction caused by the tip separation vortex, the fluid movign towards the tip gap from the pressure side is accelerated. Downstream of the vortex, the endwall pressure increases due to flow mixing. Both vortices increase in size and strength along the chord. The miring is incomplete in the aft portion of the blade. The tip gap velocity profiles exhibit wak like characteristics especially at axial positions where the mixing is incomplete. The passage vortex in the present investigations.did not diminish with increase in clearance. The discharge coefhcient and the total pressure loss coefficient within the tip gap show similar tendency with lower values near the leading and trailing edge regions.

关键词： turbine cascade tip clearance vortex tip separation vortex horse-shoe vor-tex total pressure loss coefficient discharge coefficient

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sterilization of Cotton Fabrics Using Plasma Treatment

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Plasma science and Technology 2013年第10期15卷 1031-1033页

作者： s.sHAHIDI M.GHORANNEVIss Department of Textile Faculty of EngineeringIslamic Azad University Plasma Physics Research Center Science and Research BranchIslamic Azad University

Microbial contamination induces surface deformations and strength degradation of cotton fabrics by invading deeply into the fibers. In this study, the sterilization effects of low pressure plasmas on bacteria-inoculated cotton fabrics were investigated. Oxygen plasma treatment completely sterilized the cotton fabrics inoculated with various concentrations of staphylococcus aureus. also, the influence of plasma treatment on physical properties of fabrics was examined. It was found that the plasma treatment did not affect ultimate tensile strength and surface morphology of the fabrics because it took advantage of relatively low plasma temperature.

关键词： sterilization fabri plasma treatment

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Perspectives in restoration: storage and pretreatments of seeds for better germination of sudanian savanna-woodland species

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Journal of Forestry Research 2016年第4期27卷 773-778页

作者： s.D.Dayamba P.savadogo s.Diawara L.sawadogo World Agroforestry Centre (ICRAF) West and Central Africa Regional Office - Sahel Node World Agroforestry Centre & International Crop Research Institute for the semi-Arid Tropics (ICRAF-ICRIsAT) West and Central Africa Region-Sahel Node De'partement Productions Forestie`res Centre National de la Recherche Scientifique et Technologique Institut de l’Environnement et de Recherches Agricoles

Insufficient knowledge of the germination ecology of local species is one of the main constraints to restoration of degraded rural lands. We tested seeds from fourteen sudanian savanna species targeted for restoration for their response to two different pretreatments（conventional and prolonged acid pretreatments） and two different storage conditions（ambient room conditions and refrigerator at 4 C）. For 6 of the studied species, longer soaking in sulphuric acid significantly improved germination rates and also reduced the germination time of some species. storage condition, in general did not affect germination rates except for two species where cool storage depressed germination. The practical implication is that, for the species tested, when mature seeds are collected for plantation in the upcoming rainy season, there is no need to invest in infrastructure and energy for storing in cold *** study also revealed that in general when seeds are stored in ambient conditions from the time of collection up to seeding time, although germination rate does not increase, germination time is shortened and this could be of great interest in synchronizing germination in real field conditions.

关键词： germination restoration plantation ambient mature stored ecology degraded shortened longer

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Guidance on Design of Internet-based Process Control systems

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自动化学报 2005年第1期31卷 56-63页

作者： s.H.YANG L.YANG ComputerscienceDepartment LoughboroughUniversityLoughboroughLeicestershireLE113TUUK

Internet-based process control is becoming new generations of control systems, in which the Internet is used as a platform for global remote monitoring and control. The obvious benefit is to enable global collaboration between operators from geographically dispersed locations, data sharing and data provision for remote monitoring and control. However, connection to an open network and the use of universal technology present new problems that did not exist with the conventional design and construction of control systems, such as time delay and data loss in Internet transmission and security. This paper reviews the latest research results and presents design guidance of Internet based monitoring and control systems.

关键词：网络等待时间安全性用户界面设计互联网远程监控

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施用钾和腐植酸对相同土壤性质下的小麦(Triticum Aestivum L. var. Delfii)产量和养分含量的影响

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腐植酸 2024年第3期 51-62页

作者： Mehmet DÌnCsoy Ferit sÔnmez 刘晓洁尹微罗利艳齐鹰博田佳美江志阳(译) 博卢阿邦特伊泽特贝萨尔大学农业与自然科学学院种子科学与技术系土耳其博卢14100 辽宁土木启生物科技有限公司沈阳110000 中国科学院沈阳应用生态研究所沈阳110016

于2014年至2015年进行田间试验。本研究中,选用3种K施用量(0、10和20 kg K/da)的K_2sO_4肥(50%K_2O)和3种HA施用量(0、20和40kgHA/da)的商品腐植酸(85%HA)。HA施用量的增加对试验区土壤pH、盐分、有机质、P、Mg、Fe、Mn含量的影响在P<0... 详细信息

于2014年至2015年进行田间试验。本研究中,选用3种K施用量(0、10和20 kg K/da)的K_2sO_4肥(50%K_2O)和3种HA施用量(0、20和40kgHA/da)的商品腐植酸(85%HA)。HA施用量的增加对试验区土壤pH、盐分、有机质、P、Mg、Fe、Mn含量的影响在P<0.01水平上差异显著。研究表明,K施用量的增加对试验区土壤盐分、Mg、Fe和Cu含量的影响在P<0.01水平上差异显著。HA施用量的增加对小麦生物产量、籽粒产量和收获指数有显著影响(P<0.01),而K对小麦生育期没有任何影响。HA施用量的增加对籽粒和秸秆养分含量,P、K、Ca、Mg、Fe和Zn均有显著影响(P<0.01)。K施用量的增加对P、K、Mg、Fe、Zn含量有显著影响(P<0.01)。结果表明,在改善土壤性质、作物产量和养分含量方面,施用HA比施用K更有效。

关键词：腐植酸养分钾小麦产量

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THE ELECTROCHEMICal BEHAVIOR OF OCEANIC MICROBIOLOGICal INFLUENCED CORROsION ON CARBON sTEEL

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Acta Metallurgica sinica(English Letters) 2007年第5期20卷 334-340页

作者： X.T. Chang Y.s. Yin G.H. Niu T. Liu s. Cheng s.B. sun Institute of Materials science and Technology Ocean University of China Qingdao 266003 China College of Materials science and Technology Shandong University Jinan 250061 China

The corrosion behavior of carbon steel in the medium of marine microorganisms was investigated by electrochemical impedance spectra, polarization curves, and so on. Experimental results showed that the corrosion potential of carbon steel moved in a negative direction in the unpurified marine microorganism solution, and the polarization style of the cathodic process.did not change. The electrochemical impedance spectra showed that the impedance value of the electrode decreased in the medium with bacteria, which indicated that the existence of microorganism could accelerate the corrosion progress of carbon steel.

关键词： carbon steel microbiological influenced corrosion polarization curve electrochemical impedance spectroscopy

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What actually is the Münch hypothesis?A short history of assimilate transport by mass flow

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Journal of Integrative Plant Biology 2017年第5期59卷 292-310页

作者： Michael Knoblauch Winfried s.Peters school of Biological sciences Washington State UniversityPullmanWashington 99164USA

In the 192os, the German forestry scientist Ernst M{Jnch postulated that photo-assimilate transport is a mass flow driven by osmotically induced pressure gradients between source organs （high turgot） and sink organs （lower turgor）. Two crucial components of MOnch＇s hypothesis, the translocation by mass flow from sources to sinks and the osmotic mechanism of pressure flow, were established notions at the time, but had been developed by two institutionally separated groups of scholars. A conceptual separation of wholepplant biology from cellular physiology had followed the institutional separation of forestry science from botany in German-speaking central Europe during the so-called Humboldtian reforms, and was reinforced by the delayed institutionalization of plant physiology as an academic discipline. Munch did not invent a novel concept, but accomplished an integration of the organism-focused and the cell-focused research traditions, reducing the polarization that had evolved when research universities emerged in central Europe. Post-Munch debates about the validity of his hypothesis focused increasingly on the suitability of available research methodologies, especially the electron microscope and the proper interpretation of the results it produced. The present work reconstructs the influence of the dynamic scientific and non-scientific context on the history of the Munch hypothesis.

关键词： William J. Lucas University of California Davis UsA

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Design, development and field assessment of a controlled seed metering unit to be used in grain drills for direct seeding of wheat

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Information Processing in Agriculture 2015年第3期2卷 169-176页

作者： s.Kamgar F.Noei-Khodabadi s.M.shafaei Department of Biosystems Engineering College of AgricultureShiraz UniversityShiraz 71441-65186Iran

A newcontrolled seed metering unit was designed and mounted on a common grain drill for direct seeding of wheat(DsW).It comprised the following main parts:(a)a variable-rate controlled direct current motor(DCM)as seed metering shaft driver,(b)two digital encoders for sensing the rotational speed of supplemental ground wheel(sGW)and seed metering shaft and(c)a control box to handle and process the data of the *** to the considered closed-loop control system,the designed control box regularly checked the revolution per minute(RPM)of seed metering shaft,as operation feedback,using its digital encoder *** seeding ratewas determined based on the calculated error signal and output signal of the digital encoder of the sGW.A field with four different levels of wheat stubble coverage(10%,30%,40%and 50%)was selected for evaluation of the fabricated seed metering unit(FsMU).The dynamic tests were conducted to compare the performance of installed FsMU on the grain drill and equipped grain drill with common seed metering unit(CsMU)at three forward speeds of 4,6 and 8(Km/h)for *** of the FsMU assessment demonstrated that an increase in forwardspeed of grain drill(FsGD)and stubble coverage did not significantly affect the seeding rate in the grain drill *** theFsMU reduced the coefficient of variation(CV)by approximately 50%.Consequently,applying the FsMU on the common grain drill led to a desirable seeding rate at different forward speeds of the grain drill and stubble existence.

关键词： Control box seed metering mechanism Forward speed seed drilling Field operation

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Geochemistry of Harappan potteries from Kalibangan and sediments in the Ghaggar River： Clues for a dying river

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Geoscience Frontiers 2018年第4期9卷 1203-1211页

作者： Anirban Chatterjee Jyotiranjan s.Ray Physical Research Laboratory Ahmedabad India

The ephemeral Ghaggar-Hakra River of northwestern India has always been considered to be the remnant of an ancient perennial glacier-fed river（Vedic saraswati）. The exact reason and timing of major hydrological change of this river remains speculative. The river＇s purported association with the zenith of the Harappan civilisation remains a conjecture because the timings of its fluvial past are still being debated. In this study we have made an attempt to resolve this issue using geochemical provenance of sediments from some dated horizons in the Ghaggar flood plain and that of the material used in the potteries from the Mature Harappan period（4600-3900 yr BP） at Kalibangan. sampled sedimentary horizons were dated by radiocarbon and optically stimulated luminescence（OsL） methods. Results of our study from the Ghaggar alluvium indicate that the river did have glacial sources during the early Holocene. However, the data from the potteries suggest that during the Mature Harappan period, the sediments in the Ghaggar as used by the potters.did not have a higher Himalayan provenance and hence, were not derived from glaciated *** findings imply that during the time of the Mature Harappans the Ghaggar had already become a foothill-fed river.

关键词： Ghaggar alluvium Holocene sediment provenance Mature Harappan pottery Geochemistry Vedic saraswati

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