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AUGMENTED REALITY SYSTEM FOR AIDING ENGINEERING DESIGN PROCESS OF MACHINERY SYSTEMS

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Journal of Systems Science and Systems Engineering 2011年第3期20卷 294-309页

作者： Marcin JANUSZKA wojciech MOCZULSKI Department of Fundamentals of Machinery Design Silesian University of TechnologyKonarskiego 18A44-100 GliwicePoland

The paper presents the application of augmented reality for aiding product design and development of machinery systems. Augmented reality technology integrates an interactive computer-generated word with an interactive real word in such a way that they appear as one environment. AR technology can enhance a user＇s perception of the real world with information that is not actually part of the scene but is relevant to the user＇s present activity. Presented in the AR system is a mode for changing views of data - especially 3D models - allowing the user to understand the prospective machinery system in a more comprehensive way, thus making the design process more efficient than the one supported by conventional present-day CAD systems. The presented prototype system contains an expert system integrated with AR system and allows the delivering of knowledge to the designer about successive steps of the design process of a mobile robot and practical solutions of realized constructional problems. An approach concerning AR enables the system user to analyze and verify solutions （represented as 3D models） relative to real scenes/objects. This approach is advantageous because the real environment around us often provides a vast amount of information that is difficult to duplicate in a computer. In some cases, the application of an AR system could be an optimal way to verify developed products.

关键词： Augmented reality human-computer interface CAD design for customer satisfaction computer-aided decision making

Modelling of wave transmission through a pneumatic breakwater

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Journal of Hydrodynamics 2017年第2期29卷 283-292页

作者： Maciej Paprota wojciech Sulisz Institute of Hydro-Engineering of Polish Academy of Sciences GdafiskPoland

A theoretical approach is derived to study interaction of linear water waves with an air bubble curtain used as a pneumatic breakwater. Modelling of wave transmission through an aerial barrier is a complex task due to a need to cover processes associated with wave-current interaction, effects of two-phase flows, wave damping, etc.. An initial boundary-value problem is solved by applying an efficient eigenfunction expansion method and a time-stepping procedure. The derived semi-analytical solution is used to study the effect of basic parameters of the model on wave dissipative properties of the pneumatic breakwater. Results show that wave damping by the breakwater is mainly affected by an air flow rate. The increased air discharge results in higher velocities of ascending bubbles and increases aerial barrier width. This leads to a substantial reduction of transmitted wave heights, especially for waves of intermediate length and short waves. In order to verify the applicability of the presented theoretical approach, laboratory experiments are conducted in a wave flume for different wave regimes and pneumatic breakwater characteristics. The analysis of a wave trans- mission coefficient calculated numerically and measured in the laboratory confirms that the derived model can be used for a certain range of wave conditions.

关键词： Surface waves wave transmission wave-current interaction pneumatic breakwater numerical modelling

Simulation of Fluid Flow in a Channel Induced by Three Types of Fin-Like Motion

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Journal of Bionic Engineering 2007年第3期4卷 165-176页

作者： wojciech Kowalczyk Antonio Delgado Institute of Fluid Mechanics University of Erlangen-NurembergCauerstr. 4D-91058 ErlangenGermany

One of many interesting research activities in biofluidmechanics is dedicated to investigations of locomotion in water. Some of propulsion mechanisms observed in the underwater world are used in the development process of underwater autonomic vehicles （AUV）. In order to characterise several solutions according to their manoeuvrability, influence on the surrounding fluid and energetic efficiency, a detailed analysis of fin-like movement is indispensable. In the current paper an analysis of undulatory, oscillatory and combined fin-like movements by means of numerical simulation is carried out. The conservation equation of mass and the conservation equation of momentum axe solved with the Finite Volume Method （FWM） by use of the software CFX-10.0. The undulatory and oscillatory fin movements axe modelled with an equation that is implemented within an additional subroutine and joined with the main solver. N carried out in the computational domain, in which one fin is fixed in a flow-through water duct. Simulations axe carded out in the range of the Re number up to 105. The results show significant influence of applied fin motion on the velocity distribution in the surrounding fluid.

关键词： biofluid dynamics fro-like movement fish propulsion computational fluid dynamics

Modeling of Propagation and Transformation of Transient Nonlinear Waves on A Current

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China Ocean Engineering 2013年第5期27卷 579-592页

作者： wojciech Sulisz Maciej Paprota Institute of Hydroengineering Polish Academy of Sciencies

A novel theoretical approach is applied to predict the propagation and transformation of transient nonlinear waves on a current. The problem was solved by applying an eigenfunction expansion method and the derived semi-analytical solution was employed to study the transformation of wave profile and the evolution of wave spectrum arising from the nonlinear interactions of wave components in a wave train which may lead to the formation of very large waves. The results show that the propagation of wave trains is significantly affected by a current. A relatively small current may substantially affect wave train components and the wave train shape. This is observed for both opposing and following current. The results demonstrate that the application of the nonlinear model has a substantial effect on the shape of a wave spectrum. A train of originally linear and very narrow-banded waves changes its one-peak spectrum to a multi-peak one in a fairly short distance from an initial position. The discrepancies between the wave trains predicted by applying the linear and nonlinear models increase with the increasing wavelength and become significant in shallow water even for waves with low steepness. Laboratory experiments were conducted in a wave flume to verify theoretical results. The free-surface elevations recorded by a system of wave gauges are compared with the results provided by the nonlinear model. Additional verification was achieved by applying a Fourier analysis and comparing wave amplitude spectra obtained from theoretical results with experimental data. A reasonable agreement between theoretical results and experimental data is observed for both amplitudes and phases. The model predicts fairly well multi-peak spectra, including wave spectra with significant nonlinear wave components.

关键词： numerical modeling transient waves current boundary conditions initial conditions

General neutrino mass spectrum and mixing properties in seesaw mechanisms

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Chinese Physics C 2021年第2期45卷 152-164页

作者： wojciech Flieger Janusz Gluza Institute of Physics University of SilesiaKatowicePoland Faculty of Science University of Hradec KrálovéCzech Republic

Neutrinos stand out among the elementary particles because of their unusually small *** seesaw mechanisms attempt to explain this *** this work,applying insights from matrix theory,we are in a position to treat variants of seesaw mechanisms in a general ***,using Weyl's inequalities,we discuss and rigorously prove under which conditions the seesaw framework leads to a mass spectrum with exactly three light *** find an estimate of the mass of heavy neutrinos to be the mass obtained by neglecting light neutrinos,shifted at most by the maximal strength of the coupling to the light neutrino *** provide analytical conditions allowing one to prescribe that precisely two out of five neutrinos are *** higher-dimensional cases the inverse eigenvalue methods are *** particular,for the CP-invariant scenarios we show that if the neutrino sector has a valid mass matrix after neglecting the light ones,*** the respective mass submatrix is positive definite,then large masses are provided by matrices with large elements accumulated on the ***,the Davis-Kahan theorem is used to show how masses affect the rotation of light neutrino eigenvectors from the standard Euclidean *** general observation concerning neutrino mixing,together with results on the mass spectrum properties,opens directions for further neutrino physics studies using matrix analysis.

关键词： neutrino mass matrix seesaw mechanism matrix theory

Impact of systemic steroids combined with immunosuppressive treatment on glaucomatous features in patients with systemic lupus erythematosus

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International Journal of Ophthalmology(English edition) 2022年第1期15卷 71-76页

作者： Marta P.Wiącek Danuta Bobrowska–Snarska Marek Brzosko wojciech Lubiński Monika Modrzejewska First Department of Ophthalmology Pomeranian Medical UniversitySzczecin 70-111Poland Institute of Physics University of SzczecinSzczecin 70-451Poland Department of Rheumatology Internal Medicine and GeriatricsPomeranian Medical UniversitySzczecin 71-252Poland Second Department of Ophthalmology Pomeranian Medical UniversitySzczecin 70-111Poland

AIM:To evaluate the incidence of increased intraocular pressure(IOP)and glaucomatous changes in systemic lupus erythematosus(SLE)patients in comparison with systemic steroids and immunosuppressive ***:Sixty-two women with SLE were divided into two groups:treated(n=47,94 eyes)and not treated(n=15,30 eyes)with systemic glucocorticosteroids(GC;GC-free).Twenty-one individuals in GC group were treated with immunosuppressive agents(immunomodulating and biologic).The visual acuity and IOP with ocular pulsatile amplitude(OPA)measurements,as well as scanning laser polarimetry(GDx)with nerve fiber index(NFI)measurement,spectral domain optical coherence tomography(SD-OCT)of the optic disk with retinal nerve fiber layer(RNFL)analysis and the macular region with ganglion cell analysis(GCA)were ***:Mean IOP values in group with combined GC and immunosuppressive therapy was 15.8±2.56 mm Hg and was significantly lower than in individuals with exclusive GC treatment(17.63±4.38 mm Hg,P=0.043).Contrary,no dif ferences in mean IOP values between GC-free group and individuals treated with combined GC and immunosuppressive therapy were detected(P=0.563).Similarly,mean IOP in GC was 17.14±3.94 mm Hg and in GC-free patients was equal to 16.67±3.45 mm Hg(P=0.671).According to treatment regimen no statistical differences in optic disk SD-OCT for RNFL thickness,RNFL symmetry,cupping volume and the C/D ratio were ***,no statistical differences for the mean and minimal ganglion cell layer(GCL)thickness measured in macular SD-OCT or NFI in GDx were ***:Combined immunosuppressive and systemic GC therapy in SLE patients may lower the risk of iatrogenic ocular *** relationship between treatment regimen and glaucomatous damage of optic nerve fibers in analyzed groups with SLE is detected.

关键词： immunosuppression ocular hypertension steroid induced glaucoma steroid therapy systemic lupus erythematosus

End-to-end learning of 3D phase-only holograms for holographic display

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Light(Science & Applications) 2022年第9期11卷 2176-2193页

作者： Liang Shi Beichen Li wojciech Matusik Computer Science and Artificial Intelligence Laboratory Massachusetts Institute of Technology32 Vassar StCambridgeMA 02139USA

Computer-generated holography(CGH)provides volumetric control of coherent wavefront and is fundamental to applications such as volumetric 3D displays,lithography,neural photostimulation,and optical/acoustic ***,deep learning-based methods emerged as promising computational paradigms for CGH synthesis that overcome the quality-runtime tradeoff in conventional simulation/optimization-based ***,the quality of the predicted hologram is intrinsically bounded by the dataset's *** we introduce a new hologram dataset,MIT-CGH-4K-V2,that uses a layered depth image as a data-efficient volumetric 3D input and a two-stage supervised+unsupervised training protocol for direct synthesis of high-quality 3D phase-only *** proposed system also corrects vision aberration,allowing customization for *** experimentally show photorealistic 3D holographic projections and discuss relevant spatial light modulator calibration *** method runs in real-time on a consumer GPU and 5 FPS on an iPhone 13 Pro,promising drastically enhanced performance for the applications above.

关键词： holographic synthesis overcome

A New Species Group in the Genus Tanytarsus van der Wulp (Diptera:Chironomidae) Based on a Fossil Record from Baltic Amber

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 714-719页

作者： wojciech GILKA Department of Invertebrate Zoology University of GdanskAl.Marszalka Pitsudskiego 4681-378 GdyniaPoland

A new fossil chironomid, Tanytarsus serafini, found in Baltic amber is described and illustrated based on adult males. The new species and similar extant species of the genus Tanytarsus van der Wulp are compared. Due to several distinct characters of wing, legs and bypopygium, a new species group for Tanytarsus serafini is proposed, and its diagnostic features are evaluated.

关键词： Diptera Chironomidae Tanytarsus new species Baltic amber Eocene

Environmental Risk Assessment for Exploration and Extraction Processes of Unconventional Hydrocarbon Deposits of Shale Gas and Tight Gas:Pomeranian and Carpathian Region Case Study as Largest Onshore Oilfields

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Journal of Earth Science 2020年第1期31卷 215-222页

作者： Monika Wojcik wojciech Kostowski Polish Oil and Gas Company Warszawa 01-224Poland Silesian University of Technology Institute of Thermal TechnologyGliwice 44-100Poland

Shale gas and tight gas exploration and extraction processes create potential threats to the *** Poland,no comprehensive guidelines for environmental risk assessment have been prepared so *** paper presents a proposal of environmental risk assessment methodology which can be used for corporate risk management procedures during exploration and extraction of unconventional hydrocarbons in *** most frequent environmental threats that may occur during the exploration and exploitation of unconventional hydrocarbon deposits include degradation of soils through construction of drilling rigs and access roads,landforms change,local soil pollution caused by fuels,cleaning agents and materials used to prepare drilling fluids,rubble,cement,gravel,pollution of surface and underground water as a result of emergency discharges of sewage,infiltration of pollution from waste reservoirs,disturbance of hydrogeological equilibrium through significant water intake,noise and atmospheric pollution resulting from the combustion of *** check the level of these threats' six exploration sites form Pomeranian and Carpathian region of Poland(3 wells of shale gas and 3 wells of tight gas) have been evaluated in detail,and the risk quantification has been *** of a local,short-term and reversible environment impact,the environmental risks for the exploration and extraction processes of unconventional hydrocarbons have been found to be medium or negligibly *** is recommended that using the same methodology for other regions of Poland where we can find unconventional hydrocarbons and it can be enriched in dedicated application with spatial maps to give the investors a quick feedback on the potential environmental risks.

关键词： environmental risk assessment sustainable development shale gas tight gas drilling rig environment pollution