Dynamical Field Inference and Supersymmetry

Knowledge on evolving physical fields is of paramount importance in science, technology, and economics. Dynamical field inference (DFI) addresses the problem of reconstructing a stochastically-driven, dynamically-evolving field from finite data. It relies on information field theory (IFT), the information theory for fields. Here, the relations of DFI, IFT, and the recently developed supersymmetric theory of stochastics (STS) are established in a pedagogical discussion. In IFT, field expectation values can be calculated from the partition function of the full space-time inference problem. The partition function of the inference problem invokes a functional Dirac function to guarantee the dynamics, as well as a field-dependent functional determinant, to establish proper normalization, both impeding the necessary evaluation of the path integral over all field configurations. STS replaces these problematic expressions via the introduction of fermionic ghost and bosonic Lagrange fields, respectively. The action of these fields has a supersymmetry, which means there exists an exchange operation between bosons and fermions that leaves the system invariant. In contrast to this, measurements of the dynamical fields do not adhere to this supersymmetry. The supersymmetry can also be broken spontaneously, in which case the system evolves chaotically. This affects the predictability of the system and thereby makes DFI more challenging. We investigate the interplay of measurement constraints with the non-linear chaotic dynamics of a simplified, illustrative system with the help of Feynman diagrams and show that the Fermionic corrections are essential to obtain the correct posterior statistics over system trajectories.

Effect of Gas Exchange Interval on CH4 Recovery Efficiency and Study of Mechanism of CH4 Hydrate Replacement by CO2 Mixture

As an environment-friendly natural gas hydrate exploitation method, CO2 replacement method can not only achieve the purpose of mining natural gas hydrate, but also store the current greenhouse gas CO2 in the form of hydrate on the seabed, and maintain the stratum stability of hydrate deposit area. In order to improve the rate and efficiency of CH4-CO2 replacement reaction, researchers proposed to use CO2 contained gas mixture instead of pure CO2 to replace CH4 in natural gas hydrate. Based our previous work about CH4 hydrate recovery with 40% CO2 + 60% H2, in this study, the effect of gas concentration in gas phase on final CH4 recovery are investigated by implying different time interval of gas exchange operation. Experimental results show that The CH4 recovery efficiency is 10.41 when the gas exchange is continues through the whole replacement process, and CH4 recovery efficiency changes to 12.25, 32.24 and 28.86 when gas exchange operation is carried out every 12, 24, 36 h. Indicating that replaced CH4 needs to be discharged in time to avoid CH4 molecules being replaced to form hydrates again, and it is necessary to accurately control the time interval of gas exchange operation to avoid insufficient contact time between CO2 and H2 molecules and CH4 hydrate, which affects the final replacement efficiency. In addition, the mechanism of CO2 gas mixture containing small gas molecule such as H2, N2 are studied. The results indicate that when CO2 containing small molecules such as H2 and N2 displace CH4 hydrate, the existence of small molecules (H2, N2) can give rise to decompose the hydrate lattice and release CH4 gas. If the gas molecules (CO2, N2, H2, CH4) in the gas phase have enough driving force to enter the hydrate lattice and remain stability, CH4 hydrate will not decompose completely; If not, CH4 hydrate will be completely decomposed.

Effect of the Exchanged Cation in an Algerian Montmorillonite Used as a Heterogeneous Catalyst for Biginelli Reaction

In this work, an Algerian montmorillonite (Mt) is exchanged by different cations from the transition metals family, namely: Cu2+, Ni2+, Cr3+, Co2+, Fe2+ and Fe3+, it is used as a heterogeneous catalyst for Biginelli reaction. The exchanged cations are known for their catalytic properties in homogeneous catalysis. The main purpose is to study the effect of the exchanged cations on the yield and the kinetics of the reaction. The characterization of montmorillonite was carried out by XRD, which allows us to follow the evolution of the basal spacing d001 as a function of the exchanged cation and to show that the exchange operation has not altered the montmorillonite structure. The cation exchange capacity (CEC) is determined by the titration of the exchanged cation by atomic absorption. The product of the reaction is characterized by NMR, IR and by the determination of the melting point. In addition, the importance of the introduction order of the reagents into the reaction medium has been demonstrated on the yield and the kinetics. Finally, the obtained results show that the exchanged montmorillonite is competitive with other costly heterogeneous and homogeneous catalysts.

DIAGONAL COMMUTATION MODEL FOR PARALLEL SORTING OF DATA ARRAYS

Oбъект исследования - алгоритмы параллельной сортировки с применением базовой операции «сравнение-обмен». Цель исследования - сокращение шагов работы алгоритма сортировки массива данных за счет уменьшения количества промежуточных перестановок элементов массива. Цель достигается разработкой оригинальной схемы коммутаций элементов массива. Данная схема составляет основу модели диагональных коммутаций пар элементов массива. Массив имеет 2d-представление, что позволяет объединить в пары элементы из его различных половин. За счет 2d-представления массива образуемые пары элементов позволяют уменьшить количество перестановок. Новизна модели диагональных коммутаций состоит в том, что операции «сравнение-обмен» параллельно выполняются на неконфликтующих парах элементов, взятых из различных половин массива. Это свойство модели позволяет «прыжками» перемещать элемент в необходимую позицию массива. Модель диагональных коммутаций объединена с известной моделью четно-нечетной сортировки. В результате объединения был получен алгоритм параллельной сортировки с гибридной схемой коммутации. Эта схема реализует на четных шагах предложенную модель, а на нечетных шагах - модель четно-нечетной сортировки. Моделирование алгоритмов четно-нечетной сортировки и гибридной сортировок показало преимущество разработанной модели. Расширение четно-нечетной сортировки моделью диагональных коммутаций позволяет сократить среднее число шагов сортировки. Кроме четно-нечетной сортировки, модель диагональных коммутаций применима для алгоритмов параллельной сортировки, использующих базовую операцию «сравнение-обмен» - сортировки Батчера, Шелла, слиянием The object of the research is parallel sorting algorithms using the basic operation "compare-swap". The aim of the research is to reduce the steps of the algorithm for sorting the data array by reducing the number of intermediate permutations of the array elements. The goal is achieved by developing an original switching circuit of the array elements. This circuit forms the basis of the model for diagonal commutation of pairs of array elements. The array is 2D, which allows one to pair elements from its different halves. Due to the 2D representation of the array, the formed pairs of elements allow reducing the number of permutations. The novelty of the diagonal commutation model is that the “compare-exchange” operations are performed in parallel on non-conflicting pairs of elements taken from different halves of the array. This property of the model allows one to "jump" the element to the desired position in the array. The diagonal commutation model is combined with the well-known odd-even sorting model. The combination resulted in a parallel sorting algorithm with a hybrid switching scheme. This scheme implements the proposed model at even steps, and the even-odd sorting model at odd steps. Modeling algorithms for odd-even sorting and hybrid sorting showed the advantage of the developed model. Extension of even-odd sorting by the diagonal commutation model allows to reduce the average number of sorting steps by 6-10%. In addition to odd-even sorting, the diagonal commutation model is applicable for parallel sorting algorithms using the basic comparison-exchange operation - Butcher, Shell, merge sorting

Some Novel Tricyclic Caged-Nitramines - A DFT Study

A tricyclic caged-nitramine structure having embedded RDX base has been designed. It also has three etheric linkages in the cage structure. In that sense it reminds TEX structure but it has much better oxygen balance than RDX and TEX. Then two hetero atom exchange operation (N to O replacement) at a time has been carried out to produce different isomeric structures. Through optimization process (B3LYP/6-311++G(d,p)) they have yielded some conformers and stereoisomers. The effect of heteroatom replacement on various geometrical, quantum chemical and spectral properties of the isomers have been investigated and discussed.

A Review of the Prospect and Challenges for Developing and Marketing a Brayton-Cycle Based Power Genset Gas-Turbine Using Supercritical CO2: Part I — The General System Challenges

Around the 1960s, the proposal of the supercritical dioxide (s-CCO2) power-cycle was first introduced; however, because of various obstacles, the development was slow at that time. With current worldwide emission and power problems, the s-CO2 power cycle has regained more attention because of its unique properties as a working fluid for power-cycle, and zero-emission potential. Each s-CO2 power cycle requires various components for compression, expansion, and heat exchange operation. Among various working fluid, s-CO2 has four significant advantages favorable for developers: 1. Relatively low and achievable critical conditions (∼7.3Mpa, ∼31°C). 2. The high density (∼400kg/m3) results in a very compact turbomachinery design. 3. The low dynamic-viscosity of s-CO2 can reduce the overall flow friction loss. 4. Low compressibility value which can reduce the overall system compression works. All these advantages make the s-CO2 the perfect working fluid for next-generation high-efficiency power-cycle design. This paper in two parts reviews the s-CO2 cycle technologies for power generation and critically assesses the recent challenges and development status. This paper, Part I, focuses on the general cycle concepts, thermodynamic properties, materials selection, and other components considerations.

TRANSFORMATION OF MARKET LOGISTICS IN THEORETICAL REPRESENTATION AND PRACTICAL APPLICATION

The article presents an analysis of the essence of logistics as an object of scientific research and as an organizational mechanism aimed at streamlining the functioning of commodity markets. It has been determined that such an organizational essence of logistics affects the efficiency of commodity movement along the logistics chain of the market, and, on the other hand, the efficiency of the activities of the logistics entities themselves. It is shown that the process of commodity circulation in the market is based on a commodity exchange operation. Tying the theory of logistics to the theory of commodity markets, the authors consider it expedient and reasonable to introduce the concept of "market logistics" or "market logistics" into scientific and practical circulation. On this basis, an analysis of the difference in goals, functions and mechanisms of these scientific categories is presented.