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EVOKE： A VALUE-DRIVEN CONCEPT SELECTION METHOD FOR EARLY SYSTEM DESIGN

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Journal of Systems Science and Systems Engineering 2018年第1期27卷 46-77页

作者： Marco Bertoni Alessandro Bertoni ola Isaksson GKN Aerospace Sweden AB Trollhättan Sweden

The development of new technologically advanced products requires the contribution from a range of skills and disciplines, which are often difficult to fred within a single company or organization. Requirements establishment practices in Systems Engineering （SE）, while ensuring coordination of activities and tasks across the supply network, fall short when it comes to facilitate knowledge sharing and negotiation during early system design. Empirical observations show that when system-level requirements are not available or not mature enough, engineers dealing with the development of long lead-time sub-systems tend to target local optima, rather than opening up the design space. This phenomenon causes design teams to generate solutions that do not embody the best possible configuration for the overall system. The aim of this paper is to show how methodologies for value-driven design may address this issue, facilitating early stage design iterations and the resolution of early stage design trade-offs. The paper describes how such methodologies may help gathering and dispatching relevant knowledge about the ＇design intent＇ of a system to the cross-functional engineering teams, so to facilitate a more concurrent process for requirement elicitation in SE. The paper also describes EVOKE （Early Value Oriented design exploration with KnowledgE maturity）, a concept selection method that allows benchmarking design options at sub-system level on the base of value-related information communicated by the system integrators. The use of EVOKE is exemplified in an industrial case study related to the design of an aero-engine component. EVOKE＇s ability to raise awareness on the value contribution of early stage design concepts in the SE process has been further verified with industrial practitioners in ad-hoc design episodes.

关键词： Requirements elicitation concept selection systems engineering value-driven design,decision-making knowledge maturity

Palynology and stratigraphy of the Upper Miocene Chad Formation, Bornu Basin,northeastern Nigeria

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Journal of Palaeogeography 2017年第2期6卷 108-116页

作者： A. olatunji ola-Buraimo Yunusa Abdulganiyu Department of Geology Federal University Bimin Kebbi Bimin Kebbi Nigeria

Both lithological and palynological analyses were employed to decipher sedimentary stacking patterns and to date the sediments within the interval 50—325 m in Kemar-1 well,Bornu Basin,northeastern *** different lithofacies units deposited in various environments were *** are:(1) the grayish sandy claystone,rich in organic matter and associated with lignite,deposited in a continental to lacustrine environment;(2) the micaceous claystone,rich in muscovite flakes and organic matter,deposited in a lacustrine environment;(3) the lithified claystone which intercalates the dark gray shale,and deposited in a marine setting;(4) the shale;(5) the micaceous sandstone,which is characterized by presence of muscovite,silty to granular grain sizes,well sorted and deposited in a meandering setting;(6) the poorly-sorted *** is poorly sorted,poorly-graded,and coarse-grained,with erosive surfaces to underlying facies,and deposited in a fluvial environment;(7) the heterolithic clayey sandstone,poorly graded,grayish,with a degree of organic richness,suggesting an anoxic lacustrine environment;and(8) the grayish claystone which is nonlithic and rarely ferruginized marking the Upper Miocene/Eocene *** main palynological zone,i.e.,the Echitricolporites spinosus assemblage zone,has been *** base of the studied section at 385 m is characterized by the last up-hole occurrence of Grimsdalea magnaclavata suggestive of Eocene boundary while the overlying sediments are characterized by Late Miocene marker species such as ***,Elaeis guineensis,Anthocerus sp.,Nymphaea lotus,and *** *** Chad Formation is dated as Late Miocene age unconformably overlying the Eocene Kerri-Kerri Formation which indicated that the Chad Formation was probably deposited during an alternation of lacustrine and continental settings,due to climatic change.

关键词： Palynology Lacustrine Continental Late Miocene Heterolithic Unconformity Bornu Basin Northeastern Nigeria

Biostratigraphy and palaeoenvironment of deposition of Nsukka Formation,Anambra Basin,southeastern Nigeria

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Journal of Palaeogeography 2017年第1期6卷 45-59页

作者： S.A.Bankole A.O.ola-Buraimo Department of Chemical and Geological Sciences Al-Hikmah UniversityllorinNigeria Department of Geology Federal UniversityBimin KebbiNigeria

Biostratigraphy investigation of Nsukka Formation was carried out by subjecting weLt cutting samples obtained from Nzam-1 weLL to patynotogicat studies with the view towards determining the relative geologic age and pataeoenvironment of deposition of the sediments. SampLes were treated in the Laboratory through digestion with hydrofluoric acid, sieving with 5 μm, oxidation with Nitric acid and mounting of the sLides into sections with DPX mountant. A fairLy high abundance and diversity of miospores were recovered, white the interval （847-1372 m） contains distinctive and diagnostic patynomorphs which are stratigraphicatty important. A Spinizonocolpites baculatus assemblage zone was established based on the basal occurrence of S. baculatus, Spinizonocolpites echinatus, Constructipollenites ineffectus, Periretisyncolpites sp. Periretisyncolpites giganteus, Monocolpites sp 1, Foveotriletes margaritae, Syncolporites marginatus, and Longapertites marginatus. The upper part of the intervat is marked by association of Anacolosidites luidonisis （at top）, Mauritiidites crassibaculatus, Retistephanocolpites williamsi, Proteacidites dehaani, Echitriporites trianguliformis, Proxapertites cursus, Retidiporites magdalenensis, S. baculatus, Retitricolpites gigeonetti, F. margaritae and Araucariadtes sp. The Nsukka Formation is dated as Late Maastrichtian based on the cooccurrence of recovered index fossits. Importantly, Cretaceous-Tertiary （K/T） boundary is marked by high fossil content in the Maastrichtian sediments compared to paucity in patynomorph that characterises the overtying Pateocene facies. Pataeoenvironment of the anatyzed section varies atternatety from marginaL marine to continental setting based on the presence of land-derived miospores and dinoflagettates.

关键词： Biostratigraphy Palaeoenvironment Assemblage Gonyaulacacean/Peridinacean ratio Index fossil Anambra Basin

RTP-based broadcast streaming of high definition H.264/AVC video: an error robustness evaluation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 19-26页

作者： HILLESTAD Odd Inge JETLUND ola PERKIS Andrew Centre for Quantifiable Quality of Service in Communication Systems Norwegian University of Science and Technology Trondheim N-7491Norway

In this work, we present an evaluation of the performance and error robustness of RTP-based broadcast streaming of high-quality high-definition (HD) H.264/AVC video. Using a fully controlled IP test bed (Hillestad et al., 2005), we broadcast high-definition video over RTP/UDP, and use an IP network emulator to introduce a varying amount of randomly distributed packet loss. A high-performance network interface monitoring card is used to capture the video packets into a trace file. Purpose-built software parses the trace file, analyzes the RTP stream and assembles the correctly received NAL units into an H.264/AVC Annex B byte stream file, which is subsequently decoded by JVT JM 10.1 reference software. The proposed measurement setup is a novel, practical and intuitive approach to perform error resilience testing of real-world H.264/AVC broadcast applications. Through a series of experiments, we evaluate some of the error resilience features of the H.264/AVC standard, and see how they perform at packet loss rates from 0.01% to 5%. The results confirmed that an appropriate slice partitioning scheme is essential to have a graceful degradation in received quality in the case of packet loss. While flexible macroblock ordering reduces the compression efficiency about 1 dB for our test material, reconstructed video quality is improved for loss rates above 0.25%.

关键词： H.264/AVC Video streaming Error robustness

Decreasing Arctic Sea Ice Mirrors Increasing CO_2 on Decadal Time Scale

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Atmospheric and Oceanic Science Letters 2008年第1期1卷 51-56页

作者： ola M Johannessen Mohn-Sverdrup Center for Global Ocean Studies and Operational Oceanography / Nansen Environmental and Remote Sensing Center Geophysical Institute University of Bergen

Arctic sea ice is a keystone indicator of greenhouse-gas induced global climate change, which is expected to be amplified in the Arctic. Here we directly compare observed variations in arctic sea-ice extent and CO 2 since the beginning of the 20th century, identifying a strengthening linkage, such that in recent decades the rate of sea-ice decrease mirrors the increase in CO 2 , with r ～ -0.95 over the last four decades, thereby indicating that 90% (r 2 ～ 0.90) of the decreasing sea-ice extent is empirically "accounted for" by the increasing CO 2 in the atmosphere. The author presents an empirical relation between annual sea-ice extent and global atmospheric CO 2 concentrations, in which sea-ice reductions are linearly, inversely proportional to the magnitude of increase of CO 2 over the last few decades. This approximates sea-ice changes during the most recent four decades, with a proportionality constant of 0.030 million km 2 per ppmv CO 2 . When applied to future emission scenarios of the Intergovernmental Panel on Climate Change (IPCC), this relationship results in substantially faster ice decreases up to 2050 than predicted by IPCC models. However, departures from this projection may arise from non-linear feedback effects and/or temporary natural variations on interannual timescales, such as the record minimum of sea-ice extent observed in September 2007.

关键词： CO2 increase ice decrease ice projection to2050

Production network flexibility:case study of Norwegian diary production network

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Advances in Manufacturing 2015年第2期3卷 151-165页

作者： Taravatsadat Nehzati Heidi C.Dreyer Jan ola Strandhagen Department of Production and Quality Engineering Norwegian University of Science and Technology

By increasing advances in the production net- works planning, understanding of relations and dynamics of production networks is gaining more attention in order to use all network capabilities. To achieve this under- standing, it is not only important to have a good under- standing of individual firm＇s manufacturing flexibility next to supply chain flexibility, but also to consider the internal （among production network＇s facilities） and external （other tiers of supply chain） relationships in a production network. Studying the production network＇s flexibility dimensions facilitates the effective use of the synergy of cooperation in the network. On other words, the potential in the network structure cannot be exploited unless the planning and control of network consider the available flexibility of network and operationalize the opportunities which arise. This paper identifies different dimensions of flexibility in a production network and describes how they can support firms in responding to customers＇ needs. This research employs exploratory and descriptive approaches and uses a single case study of Norwegian diary to capture the dynamics of production networks. Three product categories with different network characteristics are selected, and the identified network flexibility dimensions are investigated for these products. The status of case company under each flexibility dimension is presented and discussed.

关键词： Production network Flexibility Planning Capacity Inventory

Testicular vasomotion in different mammals

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Asian Journal of Andrology 2000年第4期2卷 297-300页

作者： ola Collin JimL.Zupp BrianP.Setchell Department of Integrative Medical Biology Section for Anatomy Umed University SwedenDepartment of Animal Science University of Adelaide AustraliaDepartment of Animal Science University of Adelaide Australia

Vasomotion is a rhythmical variation in arterial blood flow present in many different organs among them the mttestis. Vasomofion is suggested to play an important role for the transvascular fluid exchange and the exchange of nutri-ents over the capillary wall as well as the formation of interstitial fluid. The present study was undertaken to elucidatewhether vasomotion is present in the testes of different species independent of their anatomical vascular *** flow in the testes of mouse, brush-tailed possum, tammar wallaby, ram and human was investigated by using alaser Doppler fiowmeter. Vasomotion was found in all the species investigated. (Asian J Androl 2000 Dec; 2: 297-30O)

关键词： testis vasomotion human rats possum rams mice tammar-wallaby

Inflammatory processes in the liver: divergent roles in homeostasis and pathology

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Cellular & Molecular Immunology 2021年第6期18卷 1375-1386页

作者： ola Ahmed Mark W.Robinson Cliona O’farrelly School of Medicine Trinity College DublinDublinIreland Department of Biology Kathleen Lonsdale Institute for Human Health ResearchMaynooth UniversityMaynoothIreland School of Biochemistry&Immunology Trinity College DublinDublin 2Ireland

The hepatic immune system is designed to tolerate diverse harmless foreign moieties to maintain homeostasis in the healthy *** priming and regulation ensure that appropriate immune activation occurs when challenged by pathogens and tissue *** to accurately discriminate,regulate,or effectively resolve inflammation offsets this balance,jeopardizing overall tissue health resulting from an either overly tolerant or an overactive inflammatory *** scientific and clinical evidence links dysregulated hepatic immune and inflammatory responses upon sterile injury to several pathological conditions in the liver,particularly nonalcoholic steatohepatitis and ischemia-reperfusion *** and human studies have described interactions between diverse immune repertoires and nonhematopoietic cell populations in both physiological and pathological activities in the liver,although the molecular mechanisms driving these associations are not clearly ***,we review the dynamic roles of inflammatory mediators in responses to sterile injury in the context of homeostasis and disease,the clinical implications of dysregulated hepatic immune activity and therapeutic developments to regulate liver-specific immunity.

关键词： homeostasis immunology inflammation liver

Steam Pretreatment of Rice Hulls to Release Fermentable Saccharides:An Approach to Improve Recovery of(Hemi)Cellulosic Sugars Through Multivariate Design

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Rice science 2021年第5期28卷 501-510,I0037-I0039页

作者： Sheila MONTIPO Christian Roslander Marli Camassola Mats Galbe ola Wallberg Department of Chemical Engineering Lund UniversityP.O.Box 124Lund SE-22100Sweden Biotechnology Institute University of Caxias do SulCaxias do Sul 95070-560Brazil

The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the *** carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.

关键词： ligno cellulosic feedstock sulfur dioxide high solid loading hydrolysis central composite rotatable design