290 research outputs found
The contribution of N.F. Filatov the national pediatrics (to the 170 anniversary from the birthday of N.F. Filatov) (1847-1902)
No full textIt was noted that during 25 years of scientific and teaching activity N.F. Filatov has made a significant contribution to the development of world Pediatrics. He is the author of over 70 scientific works, including “a Short textbook of pediatric diseases” (1893), aged 12 editions, and “Clinical lectures” (1900). His monograph “Lectures on acute infectious diseases” (1885) through 4 editions, “Semiotics and diagnosis of childhood diseases” (1890) – 9 editions, it is translated into German, Czech, Italian, Hungarian and French. In the monographs and manuals N.F. Filatov studied many of pokoleniya-pediatricians. He described the infectious disease named Filatov scarlatinal rubella. She was later described by the British physician Duxom; one of the presently used names of the disease – a disease Filatov-Dukes. In the first edition of "Lectures on infectious diseases" N.F. Filatov described is not known until the time of infectious mononucleosis, which he called idiopathic inflammation of the cervical lymphatic glands. The disease is now often called a disease Filatov. In 1895 N.F. Filatov, described an important diagnostic sign of measles is the appearance of catarrhal period of illness 1-2 days before appearance of rash spot grayish-white lesions on the mucosa of lips and cheeks. As was established later, this sign was first described by A.P. Belsky in 1890, then regardless of him F. Filatov, and in 1896 Koplik. In the literature, this symptom is known as spots Belsky-Filatova-Koplik. N.F. Filatov described the pathogenesis of some forms of edema syndrome in children, published works on prolonged afebrile forms of the flu. N.F. Filatov developed a clinical-physiological direction in Pediatrics. He created a large school of domestic pediatricians. Among his students were V.I. Molchanov and G.N. Speransky.</jats:p
CFD modelling of an ammonium nitrate fluidised bed: effect of distribution plate geometry
No full textMEng. (Chemical Engineering), North-West University, Potchefstroom CampusFluidisation, which is a process governed by the suspension of particles in a closed area by blowing air or another medium through the bed of particles, is gaining popularity in industries like pharmaceuticals and mining, to name a few. Contributing researchers developed theory and conducted experiments in an attempt to understand this concept of fluidisation. A wide range of investigations have been conducted, but according to current knowledge, no information was reported on the fluidisation of porous granular ammonium nitrate (PGAN). According to Geldart classification, PGAN falls under Group B particles therefore the behaviour of the particles are expected to be in agreement with that was observed for sand-like particles. The aim of this study is to investigate the effect of different distributor plates on bed hydrodynamics related to an ammonium nitrate fluidised bed in laboratory-scale and pilot-scale setup by: (i) obtaining the characteristics of different suggested distributor plates for use in the fluidisation of PGAN for modelling purposes in a CFD environment, (ii) generating a CFD model for PGAN granules fluidisation that can effectively reproduce the bed pressure drop versus superficial gas velocity curve for different distributor plates using PGAN granules with different particle sizes, and (iii) devising, using the CFD model, means to determine bed density and bed expansion for the (PGAN) fluidisation operation. The plate pressure drop against superficial gas velocity curve was plotted to calculate Darcy- Forchheimer coefficients which were used in the CFD model environment to characterise the distributor plates. The plate pressure drop was found to increase with increasing superficial gas velocity. In the laboratory-scale investigation, the behaviour of the distributor plates was investigated for both a straight duct configuration and bend duct configuration below the distributor plate, while cone-shaped and column-shaped ducts were used in the pilot-scale setup. The model provided a good representation of the experimental observations for both laboratory and pilot-scale fluidisation setups. The velocity profiles obtained from employing the porousSimpleFoam solver with porous media specified by the Darcy-Forchheimer coefficients were used to generate a polynomial function which was employed to specify the boundary conditions of air in the two-phase system. The bed pressure drop versus superficial gas velocity curves resulting from modelled data follow the trend proposed in the literature, therefore the model can be used to predict the bed pressure drop of a fluidised bed system. Fluidisation initialises quicker in the predictive model than in the experimental setups. The model overestimates the bed pressure drop for particles with small average particle diameters and underestimates the bed pressure drop for particles with higher average particle diameters. The model predicts the bed pressure drop accurately at low superficial gas velocities and the error increases with an increase in superficial gas velocity. The range of minimum fluidisation velocity for all particle sizes in the laboratory scale fluidised bed was found to be 0.3-0.6 m/s. Flow patterns were discussed for particles with an average particle diameter of 1.8 mm when fluidising with a superficial gas velocity of 1.1 m/s in a model for 2 seconds. The particles were specified as alpha.particles with a void fraction of 55%. Jetting was observed in a system with a straight duct configuration below the distributor plate. It was concluded that a preferential flow resulted when employing straight ducting configurations as well as bend ducting configurations in the air inlet duct below the distributor plates, both resulting in a high final particle content towards the walls of the duct after a running time of 2s. The fluidised bed expands in general quicker in the model compared to the experiments, but little to no correspondence in behaviour was observed for a bend ducting configuration system due to preferential flow patterns observed in the system. The bed expansion ratio was found to be directly proportional to superficial gas velocity up to a certain (maximum) extent. The bed pressure drop measured along the horizontal axis of the fluidised bed in the direction of the position of the air blower at three different probe positions above the perforated plate was used to calculate bed density across the bed. There was no significant correspondence observed between the experimental bed density and the modelled bed density using plates associated with either a straight duct configuration or a bend duct configuration. A higher bed density was observed when measuring directly above the plate due to high particle content at that position. For all the plates in the pilot-scale setup, the superficial gas velocity and probe position have influenced the bed density. An increase in e.g. the height of measurement above the plate resulted in a decrease in the measured fluidised bed density.Master
The potential affordances of enterprise wikis for creating community in research networks
No full textIn this paper, we describe some of the affordances, (the specific enabling features or characteristics), of an enterprise wiki to meet the needs of a developing community of practice. The Social Innovation Network (SInet) is a nascent research network that spans the social sciences, education and commerce at the University of Wollongong. It will use the enterprise wiki software Confluence to assist in the development of communities of practice across its groups and subgroups. This paper, describes some of the features of the software and how it might be used to perform some of the common activities identified by Wenger (nd) as contributing to the development of community
The activities N.F. Pokrovsky – the first trustee of training district in Odessa
No full textУ статті на основі опублікованих джерел та архівних документів проаналізовано основні
напрямки діяльності першого піклувальника попечителя Одеського навчального округу
Н. Ф. Покровського, його внесок у розвиток освітніх установ округу, роботи по керівництву цензурним комітетом.В статье на основе опубликованных источников и архивных документов проанализированы основные направления деятельности первого попечителя Одесского учебного округа Н.Ф. Покровского, охарактеризован
его вклад в развитие образовательных учреждений округа, работа по руководству цензурным комитетом.In the article on the basis of the published sources and archival documents the author analyzes basic directions
of activity of the first trustee of the Odessa educational district N.F. Pokrovskiy. His contribution to development of
educational institutions of the district and his managing a censorship committee are studied
The activities N.F. Pokrovsky – the first trustee of training district in Odessa
No full textУ статті на основі опублікованих джерел та архівних документів проаналізовано основні
напрямки діяльності першого піклувальника попечителя Одеського навчального округу
Н. Ф. Покровського, його внесок у розвиток освітніх установ округу, роботи по керівництву цензурним комітетом.В статье на основе опубликованных источников и архивных документов проанализированы основные направления деятельности первого попечителя Одесского учебного округа Н.Ф. Покровского, охарактеризован
его вклад в развитие образовательных учреждений округа, работа по руководству цензурным комитетом.In the article on the basis of the published sources and archival documents the author analyzes basic directions
of activity of the first trustee of the Odessa educational district N.F. Pokrovskiy. His contribution to development of
educational institutions of the district and his managing a censorship committee are studied
The activities N.F. Pokrovsky – the first trustee of training district in Odessa
No full textУ статті на основі опублікованих джерел та архівних документів проаналізовано основні
напрямки діяльності першого піклувальника попечителя Одеського навчального округу
Н. Ф. Покровського, його внесок у розвиток освітніх установ округу, роботи по керівництву цензурним комітетом.В статье на основе опубликованных источников и архивных документов проанализированы основные направления деятельности первого попечителя Одесского учебного округа Н.Ф. Покровского, охарактеризован
его вклад в развитие образовательных учреждений округа, работа по руководству цензурным комитетом.In the article on the basis of the published sources and archival documents the author analyzes basic directions
of activity of the first trustee of the Odessa educational district N.F. Pokrovskiy. His contribution to development of
educational institutions of the district and his managing a censorship committee are studied
[[alternative]]Research of Moussorgsky/Ravel :"Pictures at an Exhibition"
No full text[[abstract]]Abstract
Although educated as a young officer, Moussorgky was completely a musician all his Life. With tragic characteristic, he was the most talented one among "the Russian Five". Mussorgsky composed very few piano works and even fewer orchestral works. His "Pictures at an Exhibition", born in piano form, was not popular until Ravel's orchestral arrangement was performed nearly half century later. This research about "Pictures at an Exhibition", Moussorgsky's most famous work, also one of the author's favorite, is to analyze this work.
A literature review was made including the life time of Moussorgsky, the characteristics of his music and the progress of composing "Pictures at an Exhibition". Emphases ". Emphases were also placed upon the painter Hartman, the manusaript and the premiere. Analyses of the work itself including the structure, form, the relation with the pictures, the music language. After a brief introduction of the different arrangements, studies were made regarding Maestro Ravel's orchestral arrangement. The conducting of "Pictures at an Exhibition" was discussed in detailes based on several CDs and LD, live concerts, interviews with conductors, and personal interpentation of the author.
Though emphasized on realism, Moussorgsky's colorful fantasy made people experience the natural Rassian spririt through music. With the efforts of so many arrangers and the master work of Ravel, it was proved that how possible and how progressive this piece was. No wonder Moussorgsky was considered as the most master musician of interpretating Russian soul .
Cracking and induced steel stresses of reinforced and prestressed piles during driving
No full textThe problem of steel stresses during driving of reinforced and prestressed piles in case of concrete failure is analysed in this report using a momentum trap model that includes amplitude and shape of the reflected compressive wave. Special reference is made to the different performance of reinforced and prestressed concrete piles with respect to concrete and steel failure - cracking and yielding. The significant phenomena, bond behavior, prestressing level, prestressing rate and ratio of stress wave length and pile length, are clearly distinguished for assumed linear elastic material behavior which may serve as a basis for further numerical nonlinear analysis.Design & ConstructionCivil Engineering and Geoscience
Stress wave propagation in reinforced concrete piles during driving
No full textThe aim of this report is to give an insight into what happens in a reinforced concrete pile during driving, and to contribute to design requirements for the loading case pile driving. Since the behaviour of stress waves in piles is influenced by a various number of parameters, the fewest of which result in linear relations, models are presented to calculate the initial stress wave, the reflection at the pile tip and the behaviour at a crack in the concrete. These models lead to differential equations that can be solved analytically for assumed linear material behaviour. This allows to follow the stress wave in the pile to every point and time of special interest. Case studies for different wave shapes are presented and the influence of nonlinearities discussed. Nonlinear material behaviour may be introduced, however this makes numerical solutions necessary and requires quantitative knowledge of the different parameters. Special interest is given to reflected tensile waves that may lead to cracks in the concrete. Different crack criteria are discussed and the steel stress in the reinforcement crossing the crack is calculated. The necessary amount of reinforcement then can be evaluated.Design & ConstructionCivil Engineering and Geoscience
Wireless communication systems using signal space diversity
No full textThe next generation communication devices are foreseen to not only support a large variety of applications, ranging from speech, audio and video graphics but also be able to maintain connection with many other devices (rather than a single base station) in different changing environments. The aim of the dissertation is to analyze digital modulation and coding techniques for wireless communication systems in realistic transmission scenarios. Furthermore, an important objective of the dissertation is to explore the degrees of freedom that can make the wireless communication systems overall more adaptive, thereby, resulting in systems that either consume less power for a given performance or offer more performance for a given amount of average energy than conventional systems. The techniques/algorithms analyzed in the dissertation are versatile and suitable for both narrowband as well as wideband wireless communication systems for indoor and low-mobility outdoor scenarios. Signal space diversity, also known as modulation diversity, is used to increase the overall received signal-to-noise ratio (SNR) and to reduce the probability of error. A thorough performance analysis of modulation diversity systems is presented in the thesis to understand the differences from conventional systems in narrowband and wideband channels and also to achieve the maximum possible performance. General methods are presented to optimize the system parameters and to exploit the degrees of freedom available. Channel coding, cooperative demodulation and decoding, and orthogonal frequency division multiplexing (OFDM) schemes are coupled with modulation diversity to reduce the overall power consumption and improve system performance.Electrical Engineering, Mathematics and Computer Scienc
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