Using Genetic Algorithms for Texts Classification Problems

The avalanche quantity of the information developed by mankind has led to concept of automation of knowledge extraction - Data Mining ([1]). This direction is connected with a wide spectrum of problems - from recognition of the fuzzy set to creation of search machines. Important component of Data Mining is processing of the text information. Such problems lean on concept of classification and clustering ([2]). Classification consists in definition of an accessory of some element (text) to one of in advance created classes. Clustering means splitting a set of elements (texts) on clusters which quantity are defined by localization of elements of the given set in vicinities of these some natural centers of these clusters. Realization of a problem of classification initially should lean on the given postulates, basic of which - the aprioristic information on primary set of texts and a measure of affinity of elements and classes.Comment: 16 pages, exposed on 5th International Conference "Actualities and Perspectives on Hardware and Software" - APHS2009, Timisoara, Romani

Stabilization of spectral parameters in a strontium vapor laser

The article provides a review on the laser on strontium vapor and its stabilization, considers the Lamb method and describes laser devices .Authors also consider the characteristics of a strontium vapor lase

Educational Robotics as a Factor in the Development of Network Interaction in the System of Engineering Training

Introduction. Educational robotics is a new learning technology and an effective tool for training engineering staff. Networking of educational organizations and enterprises expands their potential in the system of level engineering training. The main idea of the article is to create and test a local model of an effective networked educational system in the context of federal and regional concepts and programs that would meet the development trends of modern society and at the same time would allow the preparation of schoolchildren for real participation in practical activities. Materials and Methods. We conducted a theoretical analysis of foreign and domestic literature. The method of scientific modeling, namely, the creation of a graphic hierarchical model was applied to develop an integrated system of engineering education for schoolchildren. When organizing the practical use of the model, pedagogical design, comparative analysis of verification works, sociological tools and criterial formative evaluation are used. Results. Authors made an attempt of systematization of subjects and forms of lifelong engineering education at the stages from preschool to higher, based on research conducted over six years. It is defined that the subject of inter-agency coordination network between participants of educational organizations. A tool to ensure continuity in the transition to a new level of education, and the implementation of interdisciplinary component pre-engineering education are interdisciplinary programs, in particular, robotics. Implementation of programs on robotics is carried out through curricular and extracurricular activities, additional education program, vacation employment and other forms of work, provided resources as the base of the organization and network partners. The author’s summer program of the camp “Technosphere” was developed and approved with the day-time stay of children during the vacation period. The model of the Integrated System of Level Engineering Engineering for Schoolchildren was developed and introduced into the city’s education system. Discussion and Conclusions.The system of level engineering training, which combines the levels of education, additional educational programs and the potential of network interaction, allows to optimize all directions and forms of organization of the educational process. As a result of the study, a model of an integrated system of level engineering training at the stage of pre-school and primary general education was developed

Чувствительностью поляризационного отношения к изменениям температуры морской поверхности при зондировании в СВЧ диапазоне

The paper analyses an impact of the seawater physical-chemical characteristics on the forming radar signal in the microwave range. The analysis was carried out for the incidence angles from 25° to 75°. At these angles a recorded radar signal determines the resonant mechanism to scatter radio waves by the uneven surface. For numerical simulation we used a model based on Debye double-frequency approximation. The model describes dependence of the complex dielectric constant of water on the temperature, salinity and frequency of the sounding radio wave.A changing level of the sea surface unevenness is the main factor to determine a value of the normalized cross-section of the backscattering radio signal. The polarization ratio allows us to exclude this factor, leaving only the dependence on the incidence angle and the complex dielectric constant of water. The polarization ratio becomes dependent on the seawater temperature and salinity because at different polarizations a level of the backscattered signal has different sensitivity to these parameters. At horizontal polarization the sensitivity is higher than at vertical one.The polarization ratio sensitivity to the changes in the complex dielectric constant grows with increasing incidence angle. It also increases with decreasing radio wavelength, i.e. the greatest sensitivity is observed when sounding in the millimeter range. If the sounding is carried out at the incidence angle of 75 °, the relative change in the polarization ratio can reach 10% when the temperature changes by 5°. The relative change in the polarization ratio when sounding at an angle of 25 ° is approximately ten times lower. It is shown that changes in salinity within the limits observed in the Global Ocean lead to relatively small changes in the polarization ratio, as compared with changes due to temperature variations.Анализируется влияние физико-химических характеристик морской воды на формирование сигнала радиолокатора, работающего в СВЧ диапазоне. Анализ проводится для углов падения от 25°до 75°. При указанных углах регистрируемый сигнал локатора определяет резонансный механизм рассеяния радиоволн шероховатой поверхностью. Для численного моделирования используется модель, построенная на основе двухчастотной аппроксимации Дебая. Модель описывает зависимость комплексной относительной диэлектрической проницаемости воды от температуры, солености и частоты зондирующей радиоволны.Основным фактором, определяющим величину нормированного сечения обратного рассеяния радиосигнала является изменение уровня шероховатости морской поверхности. Использование поляризационного отношения позволяет исключить этот фактор, оставив только зависимость от угла падения и комплексной относительной диэлектрической проницаемости. Зависимость поляризационного отношения от температуры и солености морской воды возникает вследствие разной чувствительности к этим параметрам уровня рассеянного назад сигнала на разных поляризациях. На горизонтальной поляризации чувствительность выше, чем на вертикальной.Чувствительность поляризационного отношения к изменениям относительной диэлектрической проницаемости растет с ростом угла падения. Также она растет с уменьшением длины радиоволны, т.е. наибольшая чувствительность наблюдается при зондировании в миллиметровом диапазоне. Если зондирование проводится в миллиметровом диапазоне длин волн при угле падения 75°, то относительное изменение поляризационного отношения может достигать 10 % при изменении температуры на 5°. Относительное изменение поляризационного отношения при зондировании под углом падения 25° примерно в десять раз ниже. Показано, что изменения солености в тех пределах, которые наблюдаются в Мировом океане, приводят к относительно небольшим изменениям поляризационного отношения, по сравнению с изменениями, вызванными вариациями температуры

Multiwavelength metal vapor laser systems for applied spectroscopy of the atmosphere

Results from a cycle of experimental studies of a multiwavelength metal vapor laser based on an original multimedia laser configuration are reported. This approach is novel in that two gas discharge active media (strontium and copper bromide vapor) are placed in a common cavity with each pumped separately by an independent power supply. This makes it possible to optimize them independently in terms of excitation conditions and permits operational control over the set of output wavelengths and their relative power distributions. This system is attractive for a number of scientific and technological applications. The total output power was ~17 W in 11 wavelengths ranging from 0.43 to 6.45 μm

Multiwavelength metal vapor laser systems for applied spectroscopy of the atmosphere

Results from a cycle of experimental studies of a multiwavelength metal vapor laser based on an original multimedia laser configuration are reported. This approach is novel in that two gas discharge active media (strontium and copper bromide vapor) are placed in a common cavity with each pumped separately by an independent power supply. This makes it possible to optimize them independently in terms of excitation conditions and permits operational control over the set of output wavelengths and their relative power distributions. This system is attractive for a number of scientific and technological applications. The total output power was ~17 W in 11 wavelengths ranging from 0.43 to 6.45 μm

Cardiovascular effects of non-invasive ventilation in the treatment of breathing-related sleep disorders in bariatric patients

The article presents a non-systematic review of studies on breathing-related sleep disorders in patients with morbid obesity, and on the use of non-invasive ventilation in the pre-, peri-, and postoperative period of bariatric surgery, with an assessment of cardiovascular effects