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Upper limits for chlorophyll a changes with brine volume in sea ice during the austral spring in the Weddell Sea,Antarctica

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Acta Oceanologica Sinica 2016年第2期35卷 68-75页

作者： LI Zhijun LI Runling WANG Zipan haas.Christian DIECKMANN gerhard State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Department of Earth and Space Science and Engineering York University Toronto M3J1P3 Canada Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Bremerhaven D-27570 Germany

During the winter and spring of 2006, we investigated the sea ice physics and marine biology in the northwest Weddell Sea, Antarctica aboard R/V Polarstern. We determined the texture of each ice core and 71 ice crystal thin sections from 27 ice cores. We analyzed 393 ice cores, their temperatures, 348 block density and salinity samples,and 311 chlorophyll a（Chl a） and phaeophytin samples along the cruise route during the investigation. Based on the vertical distributions of 302 groups of data for the ice porosity and Chl a content in the ice at the same position, we obtained new evidence that ice physical parameters influence the Chl a content in ice. We collected snow and ice thickness data, and established the effects of the snow and ice thickness on the Chl a blooms under the ice, as well as the relationships between the activity of ice algae cells and the brine volume in ice according to the principle of environmental control of the ecological balance. We determined the upper limits for Chl a in the brine volume of granular and columnar ice in the Antarctica, thereby demonstrating the effects of ice crystals on brine drainage, and the contributions of the physical properties of sea ice to Chl a blooms near the ice bottom and on the ice-water interface in the austral spring. Moreover, we found that the physical properties of sea ice affect ice algae and they are key control elements that modulate marine phytoplankton blooms in the ice-covered waters around Antarctica.

关键词： Antarctic brine volume chlorophyll a ice crystal mode sea ice

RESILIENCE 2.0： COMPUTER-AIDED DISASTER MANAGEMENT

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Journal of Systems Science and Systems Engineering 2017年第3期26卷 321-335页

作者： gerhard Chroust Georg Aumayr Institute for Telecooperation Johannes Kepler University Linz Austria Johanniter Osterreich Ausbildung und Forschung Vienna Austria

Many factors （larger population, more dependency on technology, more human-caused interference in the natural systems and equilibria, climate changes,... ） contribute to the seemingly growing number and severity of disasters. Additional exaggeration is generated by public media. As a consequence Disaster Prevention and Disaster Management must be given increased attention. The ultimate goal of Disaster Management is resilience of the affected system and thus the adequate and acceptable survival of the affected population. We discuss system behavior in the case of an assault or disturbance： from being fragile （loss of their functionality due to the assault） to being resilient （having the capacity ... of bouncing back to dynamic stability after a disturbance）, or even antifragile （being able to ＂learn＂ so as to improve disaster resilience）. Resilience 2. 0 identifies a new paradigm： modem Information and Communication Technologies （ICT） are employed as a basis for enabling and improving resilience of a system. ICT provide the basis for sufficient preparation before an assault, for quick recognition of, and for effective, efficient reactions to disasters. Only the coordinated intra- and interphase deployment of ICT promises sufficient success and can bring resilience to currently as yet fragile systems. We discuss stressors （time and performance pressure, physical and psychological stress on personnel） and problems due to damaged ICT-platforms and communication infrastructure. The basic message is that computer-aided Disaster Management is able to offers a new level of reactivity： Resilience 2.0.

关键词： Disaster vulnerability resilience human reaction hazard threat systemic reaction

Biomimetic Sensors:Active Electrolocation of Weakly Electric Fish as a Model for Active Sensing in Technical Systems

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Journal of Bionic Engineering 2007年第2期4卷 85-90页

作者： gerhard von der Emde Zoological Institute University of Bonn53115 BonnGermany

Instead of vision, many nocturnal animals use alternative senses for navigation and object detection in their dark environment. For this purpose, weakly electric mormyrid fish employ active electrolocation, during which they discharge a specialized electric organ in their tail which discharges electrical pulses. Each discharge builds up an electrical field around the fish, which is sensed by cutaneous electroreceptor organs that are distributed over most of the body surface of the fish. Nearby objects distort this electrical field and cause a local alteration in current flow in those electroreceptors that are closest to the object. By constandy monitoring responses of its electroreceptor organs, a fish can detect, localize, and identify environmental objects. Inspired by the remarkable capabilities of weakly electric fish in detecting and recognizing objects, we designed technical sensor systems that can solve similar problems of remote object sensing. We applied the principles of active electrolocation to technical systems by building devices that produce electrical current pulses in a conducting medium （water or ionized gases） and simultaneously sense local current density. Depending on the specific task a sensor was designed for devices could （i） detect an object, （ii） localize it in space, （iii） determine its distance, and （iv） measure properties such as material properties, thickness, or material faults. Our systems proved to be relatively insensitive to environmental disturbances such as heat, pressure, or turbidity. They have a wide range of applications including material identification, quality control, non-contact distance measurements, medical applications and many more. Despite their astonishing capacities, our sensors still lag far behind what electric fish are able to achieve during active electrolocation. The understanding of the neural principles governing electric fish sensory physiology and the corresponding optimization of our sensors to solve

关键词： biomimetic weakly electric fish sensory system electrolocation sensor

Spatial modeling issues in future smart cities

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Geo-Spatial Information Science 2013年第1期16卷 7-12页

作者： gerhard SCHMITT Department of Architecture and Future Cities Laboratory ETH ZürichZürichSwitzerlandand ETH CREATESingapore

It is our goal to make today’s and future cities smart,sustainable and *** order to achieve this,it is fundamental to understand how each city works,to formalize the knowledge gained and to apply it to a city model as the base for simulations that can generate future scenarios with a high level of *** nature of this model,which must cover design,qualitative and quantitative aspects,has changed over *** this study,we focus on the role of the spatial dimension and of geometry in a city *** from being a dominating generative force in ancient cities,spatial modeling has developed into an underlying description language for present and future cities to define functions and properties of the city in space and *** example of the stocks and flows model applied to the city depicts where and how spatial modeling influences the design,construction and performance of the future Smart City.

关键词： future cities spatial modeling stocks and flows city models reality-based 3D models

THAI experimental research on hydrogen risk and source term related safety systems

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Frontiers in Energy 2021年第4期15卷 887-915页

作者： Sanjeev GUPTA Martin FREITAG gerhard POSS Becker Technologies GmbH Rahmannstrasse 11Eschborn 65760Germany

In the defense-in-depth concept employed for the safety of nuclear installations,maintaining integrity of containment as the last barrier is of high importance to limit the release of radioactivity to the environment in case of a severe *** active and passive safety systems implemented in containments of light water reactors(LWRs)are designed to limit the consequences of such *** the performance and reliability of such systems under accident conditions is critical to the safety of nuclear *** the aftermath of the Fukushima accident,there has been focus on re-examining the existing safety systems to demonstrate their capabilities for a broader range of boundary conditions comprising both the early as well as the late phases of an *** addition to the performance testing of safety systems,their interaction with containment atmosphere needs detailed investigations to evaluate the effects of operation of safety systems on H2 risk and fission product(FP)behavior in containment,which may ultimately have an impact on the source term to the *** this context,an extensive containment safety related experimental research has been conducted in a thermalhydraulics,hydrogen,aerosols,and iodine test facility(THAI,60 m3,single vessel)/(THAI+,80 m3,two interconnected vessels).Related to the subject of this paper,experimental investigations covered performance testing of various safety and mitigation systems,i.e.,containment spray,passive autocatalytic recombiner(PAR),pressure suppression pool(water pools),and effects of their operation on H2 risk and in-containment FP *** experimental results have provided a better phenomenological understanding and database for validation and further improvement of a safety analysis tool based on computation fluid dynamic(CFD)and lumped parameter(LP)modeling *** paper summarizes the main insights obtained from the aforesaid THAI experimental research covering safety systems

关键词： severe accident containment safety mitigation H2 risk source term

On the shear modulus and thermal effects during structural relaxation of a model metallic glass:Correlation and thermal decoupling

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Journal of Materials Science & Technology 2022年第8期103卷 144-151页

作者： Hongbo Zhou Vitaly Khonik gerhard Wilde Institute of Materials Physics University of MuensterWilhelm-Klemm Str.10Muenster 48149Germany Department of General Physics Voronezh State Pedagogical UniversityLenin Str.86Voronezh 394043Russia

Pd_(40)Ni_(40)P_(20)(at.%)samples with different enthalpy states were fabricated through high-pressure torsion or sub-Tg annealing of the as-cast ***,the underlying structural relaxation was studied by in-situ shear modulus measurements and modulated differential scanning *** results show that high-pressure torsion leads to shear modulus softening and an increase of the nonreversible exothermic enthalpy,indicating a significant structural rejuvenation,while sub-Tg annealing causes shear modulus hardening and a decrease of the nonreversible exothermic *** reversible endothermic effect which can reflect the fractional change of supercooled liquid with temperature was found to be almost identical for all samples,and independent of deformation or thermal *** total heat flow can be well correlated with the shear modulus within the framework of interstitialcy ***,we demonstrate that the structural relaxation below Tg decouples into internal stress relaxation andβ-*** addition,this work indicates that the processes ofα-relaxation andβ-relaxation in the metallic glass are of similar structural origin but occur on different spatial scales.

关键词： Bulk metallic glass In-situ shear modulus Thermal properties Relaxation Interstitialcy theory

Repellent effects of pongam oil on settlement and oviposition of the common greenhouse whitefly Trialeurodes vaporariorum on chrysanthemum

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Insect Science 2007年第3期14卷 219-224页

作者： ROMAN PAVELA gerhard HERDA Research Institute of Crop Production Prague Czech University of Agriculture Prague Czech Republic

The repellent activities, including host deterrence and anti-oviposion, of pongam oil against the adults of the common greenhouse whitefly Trialeurodes vaporariorum Westwood in greenhouses were tested. Chrysanthemum plants treated with different concentrations （0.5%-2.0%） of water-suspended pongam oil showed relatively long-lasting host deterrent and anti-oviposition effects on the adults of greenhouse whitefly. Although the repellent effect declined in time and concentration, strong effects on the reduction of oviposition were found, which lasts, dependent on concentration at least 12 days after application.

关键词： botanical insect control agent oviposition pongam oil repellence Trialeurodes vaporariorum

Land Monitoring Network Services based on international geospatial standards:SOSI and geoland2/SDI Projects

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International Journal of Digital Earth 2010年第S01期3卷 70-84页

作者： Stephan Meissl gerhard Triebnig EOX IT Services GmbH Thurngasse 8/41090 WienAustria

Spatial Observation Services and Infrastructure is a project to develop and verify innovative infrastructure and services within the context of land monitoring and Earth Observation initiatives at European and Member State(MS)*** project’s results contribute to the concept definition of the Shared Environmental Information System(SEIS)emphasising symmetrical online sharing of information as opposed to unidirectional *** a pre-operational set-up,involving the European Environment Agency(EEA),four MS sites and the European Space Agency(ESA),a decentralised information system respecting the Infrastructure for Spatial Information in Europe(INSPIRE)principles is demonstrated integrating distributed data and processing services as well as interactive multi-lingual *** geoland2 project is carried out in the context of Global Monitoring for the Environment and Security(GMES),a joint initiative of the European Commission and ESA,aiming to build up a European capacity for *** Spatial Data Infrastructure(SDI)task shall set up operational services for the discovery,viewing,access and delivery of all products generated in the geoland2 *** paper presents the projects along the five International Standards Organisation(ISO)/Reference Model of Open Distributed Processing viewpoints and concludes with the main recommendation that service provisioning can strongly benefit from a(re-)utilisation of the Service Support Environment(SSE)technology provided sustainably by ESA and from the related rich experience.

关键词： geoland2 SOSI INSPIRE GMES environment monitoring satellite Earth Observation

Characterization of fertility related antisperm antibodiesa step towards causal treatment of immunological infertility and immuno-contraception

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Asian Journal of Andrology 2010年第6期12卷 793-794页

作者： gerhard Haidl Department of Dermatology/Andrology Unit University of Bonn Bonn 53127 Germany

Antisperm antibodies （ASA） occur in men and women and may significantly impair fertility. The identification of functionally relevant antigens of ASA is important for establishing causal treatment options on the one hand and may, on the other hand, enhance the development of tools for immunocontraception. One candidate protein is addressed in an article of Wang et al. [1] published in Asian Journal of Andrology.

关键词： Characterization of fertility antisperm antibodies