Lower Sublevels Research Articles

Analisis Kemahiran Membaca Buku Ajar MI Berstandar American Council on Teaching of Foreign Languages (ACTFL)

This study discusses content analysis of MI Arabic textbooks for grade VI using ACTFL competency standards. This analysis will later provide a conclusion that the competency in reading the Arabic language textbook shows the appropriate level of competency standards in ACTFL. For each skill, the ACTFL guidelines identify five main levels of proficiency: Distinguished, Superior, Advanced, Intermediate, and Novice. Then start the Advanced (Advanced), Intermediate (Intermediate), and Beginner (Novice) levels. these are further divided into High, Mid, and Low sublevels, respectively. This research is a research with a qualitative approach with content or content analysis methods. Content analysis is a qualitatively oriented technique, standardized measures applied to certain units are usually used to characterize documents or compare them. The data obtained will be analyzed by the author by looking at the concept map and learning objectives of the textbook. The main purpose of writing this research is to complement existing research related to the analysis of MI Arabic textbooks with the ACTFL standard, especially in analyzing reading skills.

A preliminary analysis of the mining-induced rock movement characteristics in the Xinli deposit of the Sanshandao gold mine

Commensurate with economic globalization, the demand for mineral resources is increasing. With increased mining activity, problems related to ground subsidence and rock movement are becoming increasingly prominent, even affecting mining production activities. However, the physical mechanisms behind the ground subsidence phenomenon have been poorly studied, especially for metal mines with a steep dip. This paper applies the Interferometric Synthetic Aperture Radar (InSAR) technique and the numerical simulation method to deduce the characteristics of rock movement in the Xinli deposit of the steeply inclined Sanshandao gold mine. The InSAR results indicate that more subsidence has occurred in the southern part of the Xinli Village coastline area than in the northern part. This is also supported by the numerical simulation results obtained by the fast Lagrangian analysis of continua in three dimensions (FLAC3D). Notably, the range of ground subsidence obtained by numerical simulation shows an obvious asymmetry. The monitoring data of the No. 55 prospecting profile offer a plausible explanation for this, as the surrounding rock of the fault’s hanging wall has a wider range of rock movements. Furthermore, the sublevels of the No. 55 prospecting profile at different depths show different rock movement characteristics, and a logistic function can be well applied to the right part of the settlement curve; the parameter “a” in the function formula is very close to the maximum subsidence value for each sublevel. We defined the ratio “r” to measure the difference between the maximum subsidence value and the corresponding parameter “a” and found this value to be positively correlated with the fractal dimension value of deeper sublevels (−320 m, −400 m, −480 m, and −600 m) and negatively correlated with the fractal dimension value of lower sublevels (−200 m and −240 m).

Prolate spheroidal quantum dot: Effect of dot size and eccentricity on confined energy states

We have explored the energy states of an electron trapped in a prolate spheroidal shape CdSe quantum dot (QD) within a finite barrier height, utilizing the Schrodinger equation in a prolate spheroidal coordinate system. The calculation of various eigen energy states have been performed as a function of the QD volume and spheroid eccentricity. Our findings demonstrate that with the increase in both the QD’s volume and the eccentricity, the confinement energy decreases. Furthermore, we discovered that for any given l value, the energy of states corresponding to higher and lower sublevels (m) decreases with an increase in eccentricity. However, the decrease in energy of sublevels with increasing eccentricity varied for different m values. Additionally, a comparison of the energy states of a confined electron in prolate spheroidal and spherical quantum dots revealed that they are located at different positions.

On the efficiency of laser pumping of hyperfine structure sublevels of Rubidium-87 and Cesium-133 atoms

The evolution of the hyperfine structure magnetic sublevel populations of 87Rb and 133Cs atoms in resonant linearly polarized laser fields is theoretically analyzed. Analytical expressions are obtained for stationary populations of the magnetic sublevels of the ground state 52S1/2 Fg = 1, Ff = 2 in 87Rb and 62S1/2 Fg = 3, Ff = 4 in 133Cs under optical pumping at the Fg ↔ Fe = Fg and Ff ↔ Fe = Ff transitions of the D2 lines (n 2S1/2 n 2P3/2) versus the initial populations. The characteristic population stabilization time are obtained by numerical solution for the density matrix equations, depending on the intensity of the laser fields and the detuning of the optical resonance. It is shown that the alternation of the polarization direction of the laser field at the transition Ff ↔ Fe = Ff almost completely transfers atoms to the lower sublevel of the “clock” M1 transition Fg M = 0 ↔ Ff M = 0 in rubidium and cesium frequency standards, which proportionally increases the signal of the recording system.

Структура и оценка состояния древесных пород буковых лесов Дагестана

Aim. To identify the structural features and assess the current condition of woody species in the beech forests of Dagestan, Russia.Material and Methods. Research was based on the analysis of data from 69 sampling areas located in various physical-geographical regions of Dagestan. A detailed accounting of individual specimens of all age groups of each species was undertaken in the sampling areas. The total area surveyed was 43,125 m2. In total, 11,446 individuals of different species were involved in the statistical analysis, of which 1,974 form a tree tier, in which each individual is evaluated according to a scale of condition categories.Results. A study of the structure of beech forests showed the participation rate of Fagus orientalis Lipsky to be from 7.5 to 8.5 points. The average age of the upper sub-level of beech in the foothills was 110 years and in the highlands 160 years. For most woody species the age spectrum was sinistral and incomplete. Beech with a full-membered age spectrum were observed in the beech forests of the southwestern sub-region and in the high mountain region. A general trend is observed of deterioration of the condition of individuals in the transition from the upper to the lower sub-level. The average condition of beech individuals within the tree tier is 1.4 points. The condition categories of other species are characterized as being generally closer to 'weakened'.Conclusion. The results obtained regarding the structure and condition of woody species in the beech forests of Dagestan confirm the highly edifying role of beech. The greatest negative impact is exerted by the anthropogenic factor, which is confirmed by the incompleteness of the beech age spectrum and the low participation rate of the old-growth generative group and of the post-generative period.

Innovative trend analysis of total annual rainfall and temperature variability case study: Yesilirmak region, Turkey

It is well known that any kind of ordinary hydrometeorological parameter trend may have increasing or decreasing tendency systematically. Various methodologies are developed for possible trend identification such as the well-known Mann-Kendall test and recently Şen innovative trend analysis (ITA) approaches. The former has a set of assumptions, whereas the latter is almost without any restrictive assumption. The main purpose of this paper is to present precipitation and temperature trend behaviors by applying ITA in Yesilirmak drainage basin. Selected observation stations are mainly located at the Black Sea confluence region of Yesilirmak while few others at the middle and upper drainage basins. ITA provided visual inspection with quantitative trend slopes distinctively for low, medium, and high sub-levels with physical interpretations. Based on categorization, precipitation records have significant decreasing trends in low, medium, and high levels as an average − 3.4%, − 3.8%, and − 2.4%, respectively. In contrary to precipitation trend, and consistent to global expectation in climate change, temperature records have significantly strong increasing tendency along the basin. In sub-level of temperature, this strong trend tendencies are detected + 4.6%, + 4.8%, and + 7.2% from low to high ranges, respectively.

Spin-orbit interactions in semiconductor superlattice

The purpose of this paper is to theoretically investigate the spin-orbit interactions of common semiconductor superlattices. Spin splitting and spin-orbit interaction coefficients are calculated based on interactions between the interface-related-Rashba effect and Dresselhaus effect. Semiconductor superlattice shows a series of specific characteristics in spin splitting as follows. The spin splitting of the superlattice structure is greater than that of a single quantum well, contributing to significant spin polarization, spin filtering, and convenient manipulation of spintronic devices. The spin splitting of some superlattice structures does not change with variation of the size of some constituent quantum wells, reducing the requirements for accuracy in the size of quantum wells. The total spin splitting of lower sub-levels of some superlattice can be designed to be zero, realizing a persistent spin helix effect and long spin relaxation time, however, the total spin splitting of higher sub-levels is still appreciable, contributing to desirable spin polarization. These results demonstrate that one superlattice structure can realize two functions, acting as a spin field effect transistor and a spin filter.

Dynamics of a Spinor Exciton–Polariton System in Laterally Strained GaAs Microcavities under Resonant Photoexcitation

The evolution of the spatial coherence and the polarization has been studied in a freely decaying polariton condensate that is resonantly excited by linearly polarized picosecond laser pulses at the lower and upper sublevels of the lower polariton branch in a high-Q GaAs-based microcavity with a reduced lateral symmetry without excitation of the exciton reservoir. It is found that the condensate inherits the coherence of the exciting laser pulse at both sublevels in a wide range of excitation densities and retains it for several dozen picoseconds. The linear polarization of the photoexcited condensate is retained only in the condensate at the lower sublevel. The linearly polarized condensate excited at the upper sublevel loses its stability at the excitation densities higher a threshold value: it enters a regime of internal Josephson oscillations with strongly oscillating circular and diagonal linear degrees of polarization. The polariton–polariton interaction leads to the nonlinear Josephson effects at high condensate densities. All the effects are well described in terms of the spinor Gross–Pitaevskii equations. The cause of the polarization instability of the condensate is shown to be the spin anisotropy of the polariton–polariton interaction.

Динамика спинорной экситон-поляритонной системы в латерально сжатых GaAs микрорезонаторах при резонансном фотовозбуждении

AbstractThe evolution of the spatial coherence and the polarization has been studied in a freely decaying polariton condensate that is resonantly excited by linearly polarized picosecond laser pulses at the lower and upper sublevels of the lower polariton branch in a high-Q GaAs-based microcavity with a reduced lateral symmetry without excitation of the exciton reservoir. It is found that the condensate inherits the coherence of the exciting laser pulse at both sublevels in a wide range of excitation densities and retains it for several dozen picoseconds. The linear polarization of the photoexcited condensate is retained only in the condensate at the lower sublevel. The linearly polarized condensate excited at the upper sublevel loses its stability at the excitation densities higher a threshold value: it enters a regime of internal Josephson oscillations with strongly oscillating circular and diagonal linear degrees of polarization. The polariton–polariton interaction leads to the nonlinear Josephson effects at high condensate densities. All the effects are well described in terms of the spinor Gross–Pitaevskii equations. The cause of the polarization instability of the condensate is shown to be the spin anisotropy of the polariton–polariton interaction.

Signs of Tunneling of (n,π*) Excitation in Fluorescence of cis-Azoalkanes

We have shown that tunneling of weak residual localization of (n,π*) excitation on the original nitrogen atom of the azo group between its atoms causes splitting of the level for the excited state into two sublevels with different phase modulation frequencies, symmetries, and orientations of the fluorescence dipole moments relative to the axis of the azo bond. The phase modulation frequency for the lower sublevel of the state, antisymmetric to the direction of the N=N bond, is proportional to the level splitting. The diffuse nature of the emission spectrum from this sublevel is due to the high phase modulation frequency of the state.

Research of Mining Method for Difficult-to-Mine Ore Bodies in Deep Mine

There are many problems such as depth, high in-situ stress, high ground temperature and rockburst proneness etc. in deep mining. And it is an acknowledged and urgent mining technical puzzle about mining method of gently inclined and medium-thick ore bodies. For such an ore body in West wing of Dongguashan copper mine, if we use traditional mining method, it is hard to conquer such difficulties as high in-situ stress, large open area in roof, removal of mined ore by gravity etc. The theory of “large panel and lower sublevel height” will be easy to solve such problems. This paper use numerical technology to analyze and compare the technical and economical effectiveness for different selected mining method and its structure. The sublevel (at a height of 12 m) open stoping with back-filling by extraction in two steps is quite suitable for ensuring safety, increasing efficiency, productivity and reclaiming resource. The selected method is feasible and well worth spread.

Stochastic pulse switching in a degenerate resonant optical medium

Using the idealized integrable Maxwell-Bloch model, we describe random optical-pulse polarization switching along an active optical medium in the $\ensuremath{\Lambda}$ configuration with disordered occupation numbers of its lower-energy sublevel pair. The description combines complete integrability and stochastic dynamics. For the single-soliton pulse, we derive the statistics of the electric-field polarization ellipse at a given point along the medium in closed form. If the average initial population difference of the two lower sublevels vanishes, we show that the pulse polarization will switch intermittently between the two circular polarizations as it travels along the medium. If this difference does not vanish, the pulse will eventually forever remain in the circular polarization determined by which sublevel is more occupied on average. We also derive the exact expressions for the statistics of the polarization-switching dynamics, such as the probability distribution of the distance between two consecutive switches and the percentage of the distance along the medium the pulse spends in the elliptical polarization of a given orientation in the case of vanishing average initial population difference. We find that the latter distribution is given in terms of the well-known arc sine law.

Weighted barycentric sets and singular Liouville equations on compact surfaces

Given a closed surface, we prove a general existence result for some elliptic PDE with exponential nonlinearities and negative Dirac deltas, extending a theory recently obtained for the regular case. This is done by global methods: since the associated Euler functional might be unbounded from below, we define a new model space, generalizing the so-called space of formal barycenters and characterizing (up to homotopy equivalence) its low sublevels. As a result, the analytic problem is reduced to a topological one concerning the contractibility of this model space. To this aim, we prove a new functional inequality in the spirit of Chen and Li (1991) [11] and then employ a min–max scheme based on conical construction, jointly with the blow-up analysis in Bartolucci and Montefusco (2007) [4] (after Bartolucci and Tarantello, 2002; Brezis and Merle, 1991 [5,7]). This study is motivated by abelian Chern–Simons theory in self-dual regime, or from the problem of prescribing the Gaussian curvature with conical singularities (generalizing a problem raised in Kazdan and Warner, 1974 [24]).

Underground pressure appearance laws analysis for fully mechanized top coal slice caving on high-dipping thick coal seams

Taking Adaohai Coal Mine as the example, underground pressure appearance laws of fully mechanized top coal slice caving on high-dipping and thick coal seams. Through site visit, theoretical analysis and discrete element calculation, the research shows that, as the mining deepens, underground stress of lower sublevels is more obvious and higher than that of upper sublevels and is higher in the air return roadway than that in the air intake roadway in the area that is near to the top coal. Because the top coal is thick and gangue is caved above the support, underground pressure to the working face is relatively gentle. Immediate roof will mainly fall down along the floor. Main roof and the rock bed above the main roof will move to the mined out area along the fault in the early stage and then fall down with the mined out area later. In addition, roof pressure mainly periodically appears in two directions along the trend and the dip.

A class of existence results for the singular Liouville equation

We consider a class of elliptic PDEs on closed surfaces with exponential nonlinearities and Dirac deltas on the right-hand side. The study arises from abelian Chern–Simons theory in self-dual regime, or from the problem of prescribing the Gaussian curvature in presence of conical singularities. A general existence result is proved using global variational methods: the analytic problem is reduced to a topological problem concerning the contractibility of a model space, the so-called space of formal barycenters, characterizing the very low sublevels of a suitable functional.

Phase control of maximal atomic coherence

The atomic coherence in a three-level Λ atom is studied, in which each optical transition is driven by a coherent field and the metastable states are coupled to each other via a microwave field. It’s shown that the atomic coherence crucially depends on the relative phase delay between the envelopes of the amplitudes of the three coupling fields. In particular, when the phase delay is adjusted to 0 or π, the maximal atomic coherence arises, while the maximal atomic coherence doesn’t occur once the phase delay is changed to π/2. The maximal atomic coherence is attributed to the trapping of the population in the lower sublevels.

High resolution IR spectrum of the ν8 band of CH2DF: analysis of the interactions with the near vibrational levels

The IR spectrum of the ν8 band of monodeutero methyl fluoride has been recorded with a resolution of 0.004 cm−1 using a Fourier transform spectrometer. The ν8 vibration, of A′′ symmetry species, gives rise to a pure c-type envelope centred at 1298.58 cm−1, resembling a perpendicular band of a prolate symmetric rotor. From the spectral analysis it has been found that ν8 is coupled with ν4 for the low Ka sublevels while for the higher ones other vibrational states, directly or indirectly, are also interacting. For satisfactory reproduction of the rovibrational data of ν8, the Watson's Hamiltonian in the Ir representation has been implemented with interaction parameters, which included first- and second-order a-, b-type and c-type Coriolis couplings with ν4 and ν9, respectively. Being these states also interacting with other levels, the effective spectroscopic parameters of the analysed band up to fourth order have been obtained from a data set formed by the six fundamentals located below 1500 cm−1.

Influence of the stress state in a coal bump-prone deep coalbed: A case study

The effect of stress is one of the main natural factors that exerts a significant influence in coal bumps and rock bursts, especially in deep coalbeds. Sublevel caving is one of the methods that most influences this stress state and is therefore an extremely important parameter to consider when trying to improve mining conditions in mines with high methane content. This paper presents a practical case to illustrate the stress behavior of sub-vertical coalbeds in deep mines. The site study included two different locations, in two mines in the Riosa-Olloniego coalfield (Asturias, Spain) that are presently being mined by the sublevel caving method at a depth of around 1000 m. The research analyzed the influence that the caving of a particular panel of coal has on the upper and lower sublevels of the coalbed itself, as well as of neighboring coalbeds, with the aim of comparing different mining sequences. The site measurements carried out had two aims: to test the influence of adjacent workings on the 8th Coalbed and its coal-bearing strata and to verify the influence of the stress–strain change on the occurrence of coal bumps. Besides fulfilling these objectives, the work has also provided data for the calibration of possible numerical models that allow the simulation of present and future situations in the mine and has contributed to improving safety conditions of mining works in coal bump-prone deep coalbeds.

Suppression of coherent population trapping upon spontaneous decay of an excited state

The interaction of a model three-level Λ system with electromagnetic radiation is considered under the conditions where a coherence (an off-diagonal matrix element) between lower sublevels arises upon spontaneous decay of an excited state. The cases of bichromatic and incoherent broadband fields are analyzed. It is shown that the occurrence of coherence may significantly change the character of evolution of the system under study with time. These changes are most pronounced for broadband fields. Some features of this phenomenon are considered for multilevel atomic systems.

Model of temperature dependence for gain shape of erbium-doped fiber amplifier

The problem of modeling the temperature dependence of erbium-doped fiber amplifier (EDFAs) is important for multichannel optical WDM systems. A physical model is presented in this paper, which could be used to predict the gain change under temperature variations for such systems. Some of the input parameters for the model are the erbium energy sublevel density, excitation coefficients from lower sublevels to upper sublevels of erbium ions, and electron distribution over energy levels. It is difficult to measure these parameters. In order to use the model for gain shape calculations, some simplifications are demonstrated. These simplifications lead to two numerical models, which are shown to be consistent with experimental data with reasonable accuracy, and are based only on two spectral measurements for different temperatures. Both numerical models were tested for the signal band and the 980 nm pump band of a typical erbium-doped fiber.