Random Geometric Series

Integer sequences where each element is determined by a previous randomly chosen element are investigated analytically. In particular, the random geometric series x_n=2x_p with 0<=p<=n-1 is studied. At large n, the moments grow algebraically, n^beta(s) with beta(s)=2^s-1, while the typical behavior is x_n n^ln 2. The probability distribution is obtained explicitly in terms of the Stirling numbers of the first kind and it approaches a log-normal distribution asymptotically.Comment: 6 pages, 2 figure

Growing random sequences

We consider the random sequence x[n] = x[n-1] + yxq, with y > 0, where q = 0, 1,..., n - 1 is chosen randomly from a probability distribution P[n] (q). When all q are chosen with equal probability, i.e. P[n](q) = 1/n, we obtain an exact solution for the mean and the divergence of the second moment as functions of n and y. For y = 1 we examine the divergence of the mean value of x[n], as a function of n, for the random sequences generated by power law and exponential P[n](q) and for the non-random sequence P[n](q) = δ[q,β(n-1)]

Reconstructing Words from Right-Bounded-Block Words

A reconstruction problem of words from scattered factors asks for the minimal information, like multisets of scattered factors of a given length or the number of occurrences of scattered factors from a given set, necessary to uniquely determine a word. We show that a word $w \in \{a, b\}^{*}$ can be reconstructed from the number of occurrences of at most $\min(|w|_a, |w|_b)+ 1$ scattered factors of the form $a^{i} b$. Moreover, we generalize the result to alphabets of the form $\{1,\ldots,q\}$ by showing that at most $\sum^{q-1}_{i=1} |w|_i (q-i+1)$ scattered factors suffices to reconstruct $w$. Both results improve on the upper bounds known so far. Complexity time bounds on reconstruction algorithms are also considered here

ИССЛЕДОВАНИЕ ПУТЕЙ ОПТИМИЗАЦИИ МАТЕРИАЛОВ ДЛЯ СОЛНЕЧНЫХ БАТАРЕЙ ВТОРОГО ПОКОЛЕНИЯ МЕТОДОМ МНОГОУРОВНЕВОГО МОДЕЛИРОВАНИЯ

Theoretical analysis of optimization options for the properties of CdTe absorber layer is an important task for increasing the efficiency of CdTe/CdS heterojunction based thin−film solar cells. Properties of the materials (e.g. the density of free carriers) often depend essentially on the parameters of the deposition process and subsequent treatment which determine the defect composition of the material. In this work a model based on the lattice kinetic Monte−Carlo method is developed to describe the process of CdTe deposition as a function of temperature and Cd and Te fluxes. To determine the effect of the treatment conditions on CdTe conductivity, we developed a quasichemical model based on the electrical neutrality equation for point defects concentrations that are described by defects formation reaction constants. Parameter obtained from the first−principles density functional calculations were used when developing the models. The developed deposition model correctly describes the transition from evaporation to precipitation as well as the increased evaporation rates in excess of Cd. To explain the observed electrical properties of CdTe after Cl−treatment, we complemented the quasichemical defect model by a deep acceptor complex defect that allowed us to describe both the high−temperature dependence of conductivity on the Cd pressure and the dependence of resistivity on Cl concentration at room temperature. Теоретическое исследование путей оптимизации свойств слоя поглотителя CdTe является важной задачей на пути повышения эффективности тонкопленочных солнечных элементов на основе гетероперехода CdTe/CdS. Свойства получаемых материалов, такие как плотность свободных носителей заряда, часто сильно зависят от параметров процессов осаждения слоев и их последующей обработки, в существенной степени определяющих дефектный состав получаемых материалов. Для описания зависимости скорости процесса осаждения CdTe от температуры и потоков Cd и Te разработана модель на основе решеточного кинетического метода Монте–Карло. Для определения влияния условий обработки CdTe на проводимость разработана квазихимическая модель, основанная на уравнении электронейтральности для концентраций точечных дефектов, описываемых константами реакций образования дефектов. При разработке моделей использованы значения параметров дефектов и реакций, полученных из первопринципных расчетов с помощью теории функционала плотности. Разработанная модель осаждения корректно описывает переход от испарения к осаждению, а также повышение скорости испарения при избытке Cd. Для объяснения наблюдаемых электрических свойств CdTe после обработки Cl квазихимическая модель дефектов дополнена глубоким акцепторным комплексным дефектом, что позволило описать как высокотемпературную зависимость проводимости от давления кадмия, так и зависимость сопротивления от концентрации хлора при комнатной температуре.

ПРИМЕНЕНИЕ НАСТОЙКИ ПРОПОЛИСА ДЛЯ ПРОФИЛАКТИКИ РЕСПИРАТОРНЫХ ИНФЕКЦИЙ ЦЫПЛЯТ-БРОЙЛЕРОВ

Scientific and industrial experiment was carried out at the poultry farming on Ross308 broilers. The authors explored various schemes of application of propolis tincture for pre venting respiratory infection of poultry of bacterial etiology. The researchers arranged a control group and two experimental groups according to the principle of analogues. The groups were placed in separate isolated poultry houses. Chickens of the control group were fed with antibiotic Tilmipool (0.3 ml/l of water) aged 1-3; 14-16; 25-27 days; their poultry house was sprayed with Ecocide C (0.5%, 1 l/100 m3, exposure 60 min) on 1, 7, 14, 21-22, 28-29, 35-36 days of their life. In the 1st group the antibiotic was applied as it was in the control group; aerosol treatment was conducted with propolis tincture (dilution 1:20, 0.5 l/100 m3, exposure 60 min) during the same age periods. In the 2nd group, propolis tincture (1 ml/l of water) was applied for broilers aged 1-5; 14-18; 25-30 days combined with aerosol treatment of propolis tincture air (dilution 1:20, 0.5 l/ 100 m3, exposure 60 min) for 1, 7, 14, 21-22, 28-29, 35-36 days of their life. The most effective way to prevent respiratory diseases of poultry is seen in application of propolis tincture according to the scheme used in the experiment with the 2nd group. The scheme reduces the number of pathogenic, relatively pathogenic microorganisms in the scrapes from the laryngeal mucous membrane and in the air of the poultry house, activates the immune system and metabolism of poultry, increases livability on 3.0% and live weight on 342.7 g, which eliminates application of antibiotics for preventive measures, providing environmentally safe products of poultry farming.Научно-производственный опыт проводили в условиях птицеводческого хозяйства на цыплятах-бройлерах кросса Росс-308. Изучали различные схемы применения настойки прополиса для профилактики респираторной инфекции птиц бактериальной этиологии. С этой целью из суточных цыплят по принципу аналогов скомплектованы контрольная и две опытные группы, размещенные в отдельных изолированных птичниках. Цыплятам контрольной группы выпаивали антибиотик Тилмипул (0,3 мл/л воды) в возрасте 1-3; 14-16; 25- 27 дней и проводили аэрозольную обработку воздуха птичника Экоцидом С (0,5%, 1 л/100 м3 , экспозиция 60 мин) на 1, 7, 14, 21-22, 28-29, 35-36-й дни жизни. В 1-й группе применяли антибиотик, как в контрольной группе, аэрозольную обработку осуществляли настойкой прополиса (разведение 1:20, 0,5 л/100 м3 , экспозиция 60 мин) в те же возрастные периоды. Во 2-й группе выпаивали настойку прополиса (1мл/л воды) в возрастные периоды 1-5; 14-18; 25-30 дней в сочетании с аэрозольной обработкой воздуха настойкой прополиса (разведение 1:20, 0,5 л/ 100 м3 , экспозиция 60 мин) на 1, 7, 14, 21-22, 28-29, 35- 36-й дни жизни. Наиболее эффективным для профилактики респираторных инфекций птиц является применение настойки прополиса по схеме 2-й группы. Использование данной схемы снижает количество патогенных, условно-патогенных микроорганизмов в соскобах со слизистой оболочки гортани и в воздухе птичника, активизирует иммунную систему и обмен веществ, повышает сохранность на 3,0% и живую массу на 342,7 г, что позволяет исключить применение антибиотиков в профилактических целях, обеспечивая получение экологически безопасной продукции птицеводства

Reconstructing Words from Right-Bounded-Block Words

peer reviewedA reconstruction problem of words from scattered factors asks for the minimal information, like multisets of scattered factors of a given length or the number of occurrences of scattered factors from a given set, necessary to uniquely determine a word. We show that a word $w\in\{a,b\}^*$ can be reconstructed from the number of occurrences of at most $min(|w|_a,|w|_b)+1$ scattered factors of the form $a^ib$, where $|w|_a$ is the number of occurrences of the letter $a$ in $w$. Moreover, we generalize the result to alphabets of the form $\{1,…,q\}$ by showing that at most $\sum_{i=1}^{q−1}|w|_i(q−i+1)$ scattered factors suffices to reconstruct $w$. Both results improve on the upper bounds known so far. Complexity time bounds on reconstruction algorithms are also considered here

Greedy Solution of Ill-Posed Problems: Error Bounds and Exact Inversion

The orthogonal matching pursuit (OMP) is an algorithm to solve sparse approximation problems. Sufficient conditions for exact recovery are known with and without noise. In this paper we investigate the applicability of the OMP for the solution of ill-posed inverse problems in general and in particular for two deconvolution examples from mass spectrometry and digital holography respectively. In sparse approximation problems one often has to deal with the problem of redundancy of a dictionary, i.e. the atoms are not linearly independent. However, one expects them to be approximatively orthogonal and this is quantified by the so-called incoherence. This idea cannot be transfered to ill-posed inverse problems since here the atoms are typically far from orthogonal: The ill-posedness of the operator causes that the correlation of two distinct atoms probably gets huge, i.e. that two atoms can look much alike. Therefore one needs conditions which take the structure of the problem into account and work without the concept of coherence. In this paper we develop results for exact recovery of the support of noisy signals. In the two examples in mass spectrometry and digital holography we show that our results lead to practically relevant estimates such that one may check a priori if the experimental setup guarantees exact deconvolution with OMP. Especially in the example from digital holography our analysis may be regarded as a first step to calculate the resolution power of droplet holography