Sézary, A. et Friedmann, E. Duration of incubation in Nicolas-Favre disease. (Bull. Soc. Fr. Derm, et Syph., No. 8, 1936)

1937 ◽  
Vol 33 (7) ◽  
pp. 937-937
Keyword(s):  
Incubation Period ◽  
Experimental Studies ◽  
Point Of View ◽  
Case Histories

In recent years, the authors have observed more than 100 cases of lymphogranulomatosis. The greatest interest from the point of view of studying the duration of the incubation period in this disease deserves 11 cases, the case histories of which the authors cite in brief excerpts. In 8 cases, incubation was equal to one month, in 1 case 1 months and in 2 cases 3 months. The most probable and plausible period is 1 month. Experimental studies on animals show that they have an average incubation of 35 days. Touraine, in a debate on the authors' report, indicated that in the classical manuals and from his personal observations, the incubation period of the disease is 10-25 days.

Masonry: the brittle or plastic material?

2019 ◽  
pp. 22-28
Keyword(s):  
Plastic Material ◽  
Experimental Studies ◽  
Point Of View ◽  
Plastic Properties ◽  
Plastic Deformations ◽  
Base Materials ◽  
Stress States ◽  
Creep Deformations ◽  
Structural Point

The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.

INFLUENCE OF TECHNOLOGICAL FACTORS ON THE EFFICIENCY OF REMOVAL OF SCALE FROM FLATS FOR HOLLOW BALLS

2021 ◽  
pp. 143-147
Author(s):  
А.В. Панфилова ◽  
А.В. Королев ◽  
О.П. Решетникова ◽  
Б.М. Изнаиров ◽  
А.Н. Васин
Keyword(s):  
Rotation Speed ◽  
Experimental Studies ◽  
Surface Cleaning ◽  
Point Of View ◽  
Design Parameters ◽  
Technological Factors ◽  
Proportional Relationship ◽  
Sheet Products ◽  
Process Factors ◽  
Rolled Surface

Рассматриваются результаты проведения экспериментальных исследований способа удаления окалины с поверхности стального листового проката. Предложен новый способ и устройство для очистки поверхности листового проката от окалины режущими пластинами, вращающимися вокруг оси, перемещающейся поступательно вдоль обрабатываемой поверхности. Пластины наклонены в направлении вектора вращения на угол до 10 градусов и упруго поджимаются к обрабатываемой поверхности. Это обеспечивает возможность в процессе очистки поверхности воспроизводить макронеровности листового проката. Приведены результаты экспериментальных исследований, построены математические и графические зависимости, описывающие влияние факторов процесса на эффективность очистки поверхности проката. Показано, что наиболее значимое влияние на параметр оптимизации оказывает сила воздействия инструмента на поверхность заготовки. Причем это влияние реализуется в прямо пропорциональной зависимости. Другие исследованные факторы, а именно: угол наклона пластины, скорость ее вращения и подача, оказывают значительно меньшее влияние на степень очистки проката. Эти исследования были необходимы с точки зрения определения конструктивных параметров силовых элементов как технологической оснастки, реализующей указанный способ, так и технологической установки в целом. План эксперимента был принят, исходя из реальных производственных возможностей индустриального партнера, и соответствовал классическим представлениям теории резания. Описанные результаты дают возможность планировать дальнейшие эксперименты по изучению направлений использования данного способа Here we consider the results of experimental studies of the method of removing scale from the surface of steel sheet products. We propose a new method and device for cleaning the surface of rolled sheets from scale by cutting plates rotating around an axis moving translationally along the treated surface. The plates are tilted in the direction of the rotation vector at an angle of up to 10 degrees and are elastically pressed to the treated surface. This makes it possible to reproduce the macro-dimensions of sheet metal during the surface cleaning process. We present the results of experimental studies. We constructed mathematical and graphical dependences describing the influence of process factors on the efficiency of cleaning the rolled surface. We show that the most significant influence on the optimization parameter is exerted by the force of the tool's impact on the surface of the workpiece. Moreover, this influence is realized in a directly proportional relationship. Other factors studied, namely the angle of inclination of the plate, its rotation speed and feed, have a much smaller impact on the degree of cleaning of rolled products. These studies were necessary from the point of view of determining the design parameters of the power elements of both the technological equipment implementing this method and the technological installation as a whole. We adopted the experimental plan based on the real production capabilities of the industrial partner and corresponded to the classical concepts of the cutting theory. The described results make it possible to plan further experiments to study the directions of using the method

Recurrent Neural Networks with Small Weights Implement Definite Memory Machines

2003 ◽  
Vol 15 (8) ◽  
pp. 1897-1929 ◽  
Author(s):  
Barbara Hammer ◽  
Peter Tiňo
Keyword(s):  
Neural Networks ◽  
Recurrent Neural Networks ◽  
Experimental Studies ◽  
Activation Function ◽  
Transition Function ◽  
Recurrent Network ◽  
Point Of View ◽  
Recurrent Networks ◽  
Contraction Parameter ◽  
Arbitrary Precision

Recent experimental studies indicate that recurrent neural networks initialized with “small” weights are inherently biased toward definite memory machines (Tiňno, Čerňanský, & Beňušková, 2002a, 2002b). This article establishes a theoretical counterpart: transition function of recurrent network with small weights and squashing activation function is a contraction. We prove that recurrent networks with contractive transition function can be approximated arbitrarily well on input sequences of unbounded length by a definite memory machine. Conversely, every definite memory machine can be simulated by a recurrent network with contractive transition function. Hence, initialization with small weights induces an architectural bias into learning with recurrent neural networks. This bias might have benefits from the point of view of statistical learning theory: it emphasizes one possible region of the weight space where generalization ability can be formally proved. It is well known that standard recurrent neural networks are not distribution independent learnable in the probably approximately correct (PAC) sense if arbitrary precision and inputs are considered. We prove that recurrent networks with contractive transition function with a fixed contraction parameter fulfill the so-called distribution independent uniform convergence of empirical distances property and hence, unlike general recurrent networks, are distribution independent PAC learnable.

Лексическая неоднозначность в экспериментальных исследованиях: метаанализ

2020 ◽  
pp. 43-51
Author(s):  
Анжелика Дубасова
Keyword(s):  
Language Processing ◽  
Ambiguity Resolution ◽  
Experimental Studies ◽  
Lexical Ambiguity ◽  
Point Of View ◽  
Lexical Ambiguity Resolution ◽  
Ambiguous Words ◽  
Main Factors ◽  
The Difference ◽  
The Right

The article analyses experimental studies of lexical ambiguity (polysemy and homonymy). In total, 42 papers published between 1981 and 2017 were selected for analysis. Selected works were analyzed from the point of view of a) interaction of the main factors of lexical ambiguity resolution (meaning dominance and context), b) modularity/interactivity of language systems. The choice of these issues was caused by the fact that, despite a significant number of papers addressing them, a common theoretical model of lexical ambiguity resolution is still missing. The analysis concluded that none of the existing models could be chosen as the only true one. I believe that it is more promising to combine all models into one; in this case, we should not talk about “models” but about “algorithms” or “strategies”. This merge is compatible with the results of studies of hemispheric asymmetry, which showed that the right and left hemispheres differently process ambiguous words. This difference is projected on the difference between the two main points of view on language processing, interactive and modular. Also, as a result of the analysis, the properties of meaning dominance and context as the main factors influencing the perception of ambiguity are summarized, and the ways and possibilities of their interaction are determined. These factors can participate in the process of resolving ambiguity autonomously or together, with different functions, speed, and levels of perception.

Development of a new empirical method for Tunnel Squeezing Classification (TSC)

2020 ◽  
Vol 53 (4) ◽  
pp. 655-660 ◽  
Author(s):  
Hadi Farhadian ◽  
Arash Nikvar-Hassani
Keyword(s):  
Quality Index ◽  
Empirical Method ◽  
Point Of View ◽  
Geological Hazard ◽  
Case Histories ◽  
Proposed Model ◽  
Two Parameters ◽  
Classification Tool ◽  
Selection Of

The characterization of squeezing phenomena as a geological hazard is of great importance because squeezing has a crucial role in the selection of the route and type of tunnels and in the characteristics of the excavation device. Tunnel squeezing is also the basis for the designation and construction of tunnelling-related structures. We present a new tunnel squeezing classification tool to predict tunnel squeezing based on two parameters: Q, the tunnelling quality index; and H, the depth of the tunnel. We used data collected from published papers to train the model; these data included 225 case histories from different countries, including Andorra, India, Iran, Japan, Nepal, Spain, Turkey and Venezuela. Validation of the model indicated that our tunnel squeezing classification tool is more accurate than the speculative and analytical methods currently in use. The proposed model will help tunnelling experts to classify tunnelling media from the point of view of squeezing hazards.

scholarly journals Optimization of plastic foam composition for insulation systems

2019 ◽  
Vol 91 ◽  
pp. 02017 ◽  
Author(s):  
Anton Pilipenko ◽  
Ekaterina Bobrova ◽  
Alexey Zhukov
Keyword(s):  
Heat Loss ◽  
Experimental Studies ◽  
Point Of View ◽  
Structural Safety ◽  
Vapor Permeability ◽  
Building Structures ◽  
Polystyrene Foam ◽  
Building Systems ◽  
Insulation Systems ◽  
Extruded Polystyrene Foam

Construction insulation systems should provide solutions to the problems of creation of suitable conditions of load-bearing construction elements and whole construction, reduction of heat loss through thermal insulation layer, and creation of living comfort in buildings. The article presents the results of experimental studies, the purpose of which is to optimize the composition of extruded polystyrene foam, the formation of methods for selecting its composition and the development of systems for the use of products based on extruded polystyrene foam. Main provisions of the method of analytical optimization, which allows significantly reducing the material and time costs for processing the experimental results, are also provided. Aspects of the implementation of building systems using extruded polystyrene foam both from the point of view of minimizing heat loss through contact areas and the degree of influence of vapor permeability of building structures on the temperature and humidity conditions of premises are studied. Mandatory criteria for construction with the use of building systems are safety conditions, including both structural safety (including maintenance-free cycle) and fire safety.

The jet density exponent issue for the noise of heated subsonic jets

1974 ◽  
Vol 64 (3) ◽  
pp. 611-622 ◽  
Author(s):  
R. Mani
Keyword(s):  
Speed Of Sound ◽  
Plug Flow ◽  
Experimental Studies ◽  
Acoustic Power ◽  
Point Of View ◽  
Ambient Fluid ◽  
Simple Assumption ◽  
Exit Velocity ◽  
Radiative Efficiency ◽  
Flow Round

The subject of the present study is the question of how the sound power of a jet of constant exit velocity would vary if the jet exit density were varied. Changes in jet exit density would inevitably be accompanied in a real experiment by changes in the speed of sound (temperature) in the jet, so that both effects must be considered simultaneously. The point of view advanced at the end of the study is that experimentally observed results in this area seem to admit an explanation based on how the radiative efficiency of moving acoustic sources is affected by the shrouding effect of a jet flow whose velocity, temperature and density differ from those of the ambient fluid. This change in efficiency is calculated with the aid of a simple model as follows. We determine the acoustic power output of a convected monopole source, simple harmonic in its own frame of reference, moving along the axis of a plug-flow round jet whose velocity is the same as that of the source. The jet is doubly infinite and the source is assumed to have an infinite lifetime. The density and temperature of the jet are allowed to differ from those of the ambient fluid though the specific-heat ratio of the jet fluid is assumed to be the same as that of the ambient. The requirement of equality of the static pressure inside and outside the jet then calls for a certain restraint on how the jet density and temperature vary. For a specific value of the jet exit velocity, the variation of acoustic power with the ratio of jet to ambient density along with a simple assumption on how the source strength varies with jet density are employed to deduce theoretically the ‘jet density exponent for jets which are subsonic with respect to the ambient speed of sound. The jet density exponent is found to depend both on the jet Mach number and even more strongly on a source frequency parameter. The theoretical results are compared with some experimental studies of this problem. Encouraging agreement is obtained both for the detailed observed effects on the power spectrum and the exponent for the overall power.

Numerical and Experimental Studies of Pendulum Dynamic Vibration Absorber for Structural Vibration

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Seon Il Ha ◽  
Gil Ho Yoon
Keyword(s):  
Experimental Studies ◽  
Point Of View ◽  
Structural Vibration ◽  
Vibration Absorber ◽  
Square Root ◽  
Vibration Absorbers ◽  
Structural Vibrations ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Resonance Frequencies

Abstract This research presents a pendulum dynamic vibration absorber (PDVA) consisting of a spring and a mass in order to attenuate structural vibrations at two frequencies of hosting structure. It is a convention to attach several dynamic absorbers to hosting structure for the sake of the attenuations of structural vibrations at multiple frequencies with enlarged bandwidth and often it increases the total mass and the installation cost. Therefore, the reduction of the number of vibration absorbers for multiple excitation frequencies is an important issue from an engineering point of view. To resolve these difficulties, this study proposes to adopt the vibration absorber framework of the spring-mass vibration as well as the pendulum vibration simultaneously with the present PDVA system. It is composed of a spring and a mass but being allowed to swing circumferentially, the structural vibrations at the two resonance frequencies, i.e., the square root of stiffness over mass and the square root of a length over gravidity, can be simultaneously attenuated. As the length of the spring of the present PDVA is varied, the effective ranges for the pendulum dynamic vibration absorber become widen. To prove the concept of the present PDVA, this research conducts several numerical simulations and experiments.

THE PROBLEM OF PROVIDING GUARANTEES ON THE QUALITY OF MILITARY SPECIALISTS’ TRAINING: RESULTS OF EXPERIMENTAL STUDIES

2019 ◽  
pp. 50-55
Author(s):  
Y. Chernykh ◽  
O. Chernykh
Keyword(s):  
Professional Competence ◽  
Educational Institution ◽  
Research Work ◽  
Experimental Studies ◽  
Educational Process ◽  
Point Of View ◽  
Professional Activity ◽  
Sociological Study ◽  
Military Institute

The article examines the quality of training of cadets – the graduates of higher military educational institutions and military educational units of higher education institutions (hereinafter – HMEI). The quality of training is assessed by future officers as the main components of their own competencies. The main factors contributing to the improvement of the quality of military specialists’ training are analyzed.In order to assess the quality of training of military specialists during the implementation of research work among graduates of HMEI, a sociological study has been conducted. The main attention is paid to the problem of identifying the current state of the quality of training of military specialists and the identification of factors that will increase the effectiveness of the educational process in the HMEI. The sample was taken in seven leading HMEI: National Army Academy, Kharkiv National Air Force University, Military Academy (Odesa), Institute of Armored Forces of National Technical University “Kharkiv Polytechnic Institute”, Zhytomyr Military Institute, the Military Institute of Telecommunications and Informatization, Military Institute of Taras Shevchenko National University of Kyiv.The quality of training of military specialists was considered from the point of view of graduates’ self-examination, namely: awareness of their own professionalism; possibilities of realization of individual abilities and inclinations; mastering the methodology of self-education, self-improvement; psychological readiness for professional activity; competence; ability to perform employment duties in the troops successfully.When planning a sociological study, all questions were brought together into five main blocks: socio-demographic characteristics of respondents; level of readiness of graduates to perform employment duties in troops, forces (the formation of appropriate competencies); changes (directions of improvement) in the content and methods of studying in HMEI offered by graduates to improve the quality of their own training; organizational measures that, in future officers’ opinion, should be used to improve the quality of training of military specialists; factors that are more of a concern for graduates after completing their studies;Key words: quality of training, professional competence, graduate of higher military educational institution, sociological survey

scholarly journals Influence of a rotating nozzle diaphragm on the characteristics of axial low-consumption turbines

2021 ◽  
pp. 86-89
Author(s):  
С.В. Чехранов ◽  
Р.Р. Симашов
Keyword(s):  
Experimental Studies ◽  
Point Of View ◽  
Working Fluid ◽  
Running Wheel ◽  
Flow Angle ◽  
Wide Range ◽  
Axial Turbines ◽  
External Loads ◽  
Large Flow ◽  
Low Consumption

Экспериментально исследуются различные компоновки турбинных ступеней с целью обеспечения многорежимности у осевых малорасходных турбин. Определено, что под многорежимностью понимается способность турбины поддерживать величину КПД неизменной, или с небольшими изменениями в достаточно широком диапазоне изменения внешних нагрузок. С новой точки зрения обращено внимание на то, что наиболее выраженными свойствами многорежимности обладают турбины в состав которых входит вращающийся сопловой аппарат. В этой связи рассмотрены авторские результаты экспериментальных исследований биротативных турбин с большим углом поворота потока и двух-ступенчатых осевых турбин с частичным облопачиванием рабочего колеса. Выявлено, у исследованных биротативных турбин свойство многорежимности проявляется при степени парциальности, близкой к единице и регулируется путем изменения соотношения частот вращения соплового аппарата и рабочего колеса. А у одновальных турбин с частичным облопачиванием рабочего колеса свойство многорежимности проявляется в широком диапазоне изменения степени расширения в турбине также при полном подводе рабочего тела. Various arrangements of turbine stages are experimentally investigated in order to ensure multiplicity of operating levels for axial low-consumption turbines. It has been determined that multiplicity is understood as the ability of a turbine to maintain the efficiency value unchanged, or with small changes in a fairly wide range of external loads. From a new point of view, attention is drawn to the fact that the most marked properties of operating levels multiplicity are relevant to the turbines which include a rotating nozzle diaphragm. In this regard, the author's results of experimental studies of birotative turbines with a large flow angle and two-stage axial turbines with partial blading of the running wheel are considered. It was revealed that in the investigated birotative turbines the property of multiplicity is manifested at a degree of partiality close to 1 and is regulated by changing the ratio of the rotation frequencies of the nozzle diaphragm and the running wheel. And in single-shaft turbines with partial blading of the running wheel, the multiplicity property is manifested in a wide range of changes in the degree of expansion in the turbine, also with full supply of the working fluid.

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