检索结果-南通市图书馆

STOCK LOAN VALUATION UNDER A REGIME-SWITCHING MODEL WITH MEAN-REVERTING AND FINITE MATURITY

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2010年第3期23卷 572-583页

作者： david PRAGER Department of Mathematics University of Georgia

Stock loans are business contracts between borrowers and lenders in which the borroweruses shares of stock as collateral for the *** the value of the collateral is subject to wide andfrequent price swings,valuing such a transaction behaves more like an option pricing problem thana debt valuation *** paper will list,prove,and analyze formulas for stock loan valuationwith finite horizon under various stock models,including classical geometric Brownian motion,meanreverting,and two-state regime-switching with both mean-reverting and geometric Brownian *** examples are reported to illustrate the results.

关键词： Mean reversion regime switching stock loan.

Predictions of decreased surface roughness after shot peening using controlled media dimensions

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第23期58卷 120-129页

作者： Siavash Ghanbari david F.Bahr School of Materials Engineering Purdue UniversityWest LafayetteIN47907USA

Shot peening induces residual compressive stresses on metallic substrates, often used to decrease fatigue crack growth. The relationship between surface roughness and the magnitude of the stress can be affected by peening media size or the extent of peening. Generally, an ideal condition from shot peening would be a high compressive residual stress and a low surface roughness, but these tend to be inversely *** study proposes a method for decreasing roughness and increasing residual stress concurrently using a distribution of shot sizes in a single shot peening passage based on finite element modeling that has been calibrated using by experimental results. Numerical models predict mixed shot sizes will create a smoother surface than using monodispersed shot at 100 % coverage. The residual stress profile for mixed shot sizes showed a broad range of compressive residual stresses in comparison with the largest impact ball size. This newly proposed method can improve the surface quality and the extent of the compressive residual stresses in a single-shot peening passage.

关键词： Numerical analysis Shot peening Roughness

A fast and accurate model for the creation of explosion fragments with improved fragment shape and dimensions

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2022年第2期18卷 159-169页

作者： david Felix Ian Colwill Paul Harris School of Computing Engineering&MathematicsUniversity of BrightonBrightonUK Engineering and Design(Alumni) University of SussexBrightonUK

Explosion models based on Finite Element Analysis(FEA)can be used to simulate how a warhead *** their execution times are *** protection systems need to make very fast predictions,before a fast attacking weapon hits the *** execution times are also needed in real time simulations where the impact of many different computer models is being ***,FEA explosion models are not appropriate for these real-time *** research presented in this paper delivers a fast simulation model based on Mott’s equation that calculates the number and weight of fragments created by an *** addition,the size and shape of fragments,unavailable in Mott’s equation,are calculated using photographic evidence and a distribution of a fragment’s length to its *** model also identifies the origin of fragments on the warhead’s *** results are verified against experimental data and a fast execution time is achieved using uncomplicated simulation *** developed model then can be made available for real-time simulation and fast computation.

关键词： Distribution of fragments Fragment shape Real-time simulation Cylindrical explosion

Ricochet quantification using a multiple sensor approach

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2021年第2期17卷 305-314页

作者： Michael Muster Amer Hameed david Wood Centre for Defence Engineering Cranfield UniversityDefence Academy of the United KingdomShrivenhamSN68LAUK

This study investigates the ricochet behaviour of three different small-arms projectile types using a novel ricochet measuring *** results can be used to estimate the danger potential of ricochets on shooting ranges.A ricochet is the change of direction and velocity of a projectile after impacting an oblique *** impact produces strong vibrations on a rigid *** this impact,flexural waves travel radially outwards from the point of *** waves are used to determine the properties of the impactor with accelerometers situated on the target *** the use of two measurement plates,one can produce a ricochet and detect the velocity at the same *** are suitable for accurate momentum measurements of single ***,depending upon strike velocity and the impact angle,a ricochet can separate in multiple fragments after being *** the operational safety perspective,these fragments need to be detected,as *** approach of a coupled sensor concept was chosen to solve this *** sensors were additionally used to visualise the heat which is produced after penetrating a rubber layer pasted in front of the steel target *** this approach one was able to detect the position of *** investigations showed that the measurement system performance is better with a multiple sensor design,which includes accelerometers for the velocity,impact strength and partly the position measurement,while the thermographic sensor was used for the position measurement and partly the momentum *** investigated ammunition showed plausible fragmentation behaviour,and the results can already be used to estimate the danger potential of different ammunition *** projectiles fragment to small particles already after being deflected under a small ***,Full Metal Jacket projectiles with or without a steel core do not fragment under angles which are less than 5.The objective of the pa

关键词： Ricochet analysis Small-calibre ammunition Velocity measurement Thermography

Pico-washing:simultaneous liquid addition and removal for continuous-flow washing of microdroplets

在线全文

学校读者我要写书评

暂无评论

Microsystems & Nanoengineering 2022年第2期8卷 249-261页

作者： Michael J.Siedlik david Issadore Department of Bioengineering University of PennsylvaniaPhiladelphiaPA 19104United States

Droplet microfluidics is based on a toolbox of several established unit operations,including droplet generation,incubation,mixing,pico-injection,and *** the last two decades,the development of droplet microfluidic systems,which incorporate these multiple unit operations into a workflow,has demonstrated unique capabilities in fields ranging from single-cell transcriptomic analyses to materials *** unit operation that is sorely underdeveloped in droplet microfluidics is washing,exchange of the fluid in a droplet with a different ***,we demonstrate what we name the"pico-washer,"a unit operation capable of simultaneously adding fluid to and removing fluid from droplets in flow while requiring only a small footprint on a microfluidic *** describe the fabrication strategy,device architecture,and process parameters required for stable operation of this technology,which is capable of operating with kHz droplet ***,we provide an image processing workflow to characterize the washing process with microsecond and micrometer ***,we demonstrate the potential for integrated droplet workflows by arranging two of these unit operations in series with a droplet generator,describe a design rule for stable operation of the pico-washer when integrated into a system,and validate this design rule *** anticipate that this technology will contribute to continued development of the droplet microfluidics toolbox and the realization of novel droplet-based,multistep biological and chemical assays.

关键词： operations simultaneous removing

Analysis of the effect of bore centerline on projectile exit conditions in small arms

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2022年第12期18卷 2160-2169页

作者： david Leonhardt Mark Garnich Miljenko Lucic College of Engineering University of CanterburyPrivate Bag 4800Christchurch8140New Zealand Novacam Technologies Inc. 277 Lakeshore Road Suite#4Pointe-ClaireQuebecH9S 4L2Canada

Most finite element models of small arms focus on an idealized barrel,typically one with a perfectly straight bore *** five different experimentally measured bore centerlines,this investigation analyzes the effect centerline nonlinearity has on projectile exit *** includes the effect of rotating a centerline through several *** using Abaqus/Explicit,this dynamic analysis simulates a single firing cycle for each *** jump is calculated for each model as a measure of the effects of warped *** warped centerlines have a small effect on barrel dynamics.

关键词： Finite element analysis Small arms Barrel dynamics Bore centerline

Olfactory dysfunction as a common biomarker for neurodegenerative and neuropsychiatric disorders

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2023年第5期18卷 1029-1030页

作者： david Slabik Olga Garaschuk Department of Psychiatry and Psychotherapy Tübingen Center for Mental HealthEberhard Karls University of TübingenTübingenGermany Institute of Physiology Department NeurophysiologyEberhard Karls University of TübingenTübingenGermany

The sense of smell supports the identification and the safety of food,warns of danger/predators,and plays a key role in mating(Croy and Hummel,2017;Kondo et al.,2020;Tzeng et al.,2021).Via connection to the limbic system,it supports behavioral adaption and emotions and can detect fear,tears,and happiness in the body odor of others(Croy and Hummel,2017;Tzeng et al.,2021).

关键词： Kondo tears al.

Forest visualization at multiple scales for management and planning

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2006年第z1期49卷 27-34页

作者： david J.Mladenoff Department of Forest Ecology and Management

In this study forests were visualized at various scales by placing individual trees into a forest with realistic sizes and densities. Tree images were used from two sources: high quality field photos and images created using graphic design software. The terrain, species composition, and tree sizes and density from forest inventory were all represented in GIS data format. In addition, non-tree objects and features that are essential for close-to-reality visualization were combined with the tree images in a 3-D visualization software package. We further portrayed stand level effects by animating a simulated fly-through of a forest. To visualize temporal change, a case study of four different forest patches was animated. The advantages of this approach comparing to other visualization approaches are: (1) it represents the forests with realistic individual tree images; and (2) it maintains both visual and informational realism in a forest viewable from within-stand to landscape scales. Thus, this approach is realistic in two aspects. First, it is almost as realistic as a photograph, and secondly, its information content is actual forest composition, density, and height.

关键词： 3-D, visualization, forest, landscape, multiple scales.

Ferroptosis:copper-iron connection in cuprizone-induced demyelination

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2022年第1期17卷 89-90页

作者： Priya Jhelum Samuel david Centre for Research in Neuroscience and Brain Program The Research Institute of the McGill University Health CentreMontrealQCCanada

Redox active metals such as iron,copper,zinc,and manganese play important roles in promoting a variety of biochemical reactions essential for cellular *** is made possible by the ability of these metals to accept and donate *** in the form of iron-sulfur clusters and heme plays a key role in adenosine triphosphate generation in mitochondria as well as numerous other enzymatic *** the other hand.

关键词： function. copper metals