Two-dimensional Index Research Articles

Effect of large deflection angle on the laser intensity profile produced by acousto-optic deflector scanners in high precision manufacturing

Laser beam scanners have found wide applications in a variety of laser-assisted advanced microprocessing technologies such as printing, patterning, and doping. Traditional galvo-scanners affect the accuracy of beam positioning and repeatability in high precision manufacturing due to mechanical motion of the mirrors and backlash errors. The purpose of this study is to analyze an acousto-optic deflector (AOD) to achieve high diffraction efficiency and high deflection angle. Conventional AODs are operated with one-dimensional refractive index variation induced by modulating only the acoustic wave frequency. The effect of two-dimensional refractive index variations, which can be achieved by modulating both the phase and frequency of the acoustic waves, is analyzed. This study, therefore, advances the current AOD technology from just acoustic wave frequency modulation to a new class of AODs involving both phase and frequency modulations. This new type of AOD is designed by developing an analytic model based on the propagation of a laser beam through the AOD in which the refractive index varies in two dimensions. The model predicts a specific index modulation strength to achieve 100% diffraction efficiency. Also a fairly large diffraction efficiency can be obtained over a large angle of incidence, which is not possible in conventional AODs where the maximum diffraction efficiency occurs only at Bragg angle of incidence.

An Entropy-Robust Optimization of Mobile Commerce System Based on Multi-agent System

Today, mobile commerce is very popular, but all kinds of risks or uncertainties may result in very serious impacts in its development because of its open environment. Therefore, the robust operation and optimization of the mobile commerce system are discussed here. Firstly, a mobile commerce system with uncertainty is modelled as a multi-agent system, as well as its characteristics and related definitions. Secondly, the entropy evolution mechanism of the system is illustrated by entropy flow analysis, and the entropy robustness is also defined based on which the mobile commerce system is described as a system set with an exact part and an uncertain one. Thirdly, a two-dimensional entropy robustness index is presented including the space robustness and time robustness, by which the interaction mechanism of different uncertainties can be analysed and optimized. Lastly, self-organization behaviour and coupling operation of the proposed model are simulated and verified by a dynamics evolution experiment. The proposed model can realize data visualization of multi-agent system under uncertainty, providing a helpful tool for robust optimization of mobile commerce.

Real-time multi-class object detection using two-dimensional index

When there exists only one sample for each category of objects, previous approaches of training multi-class classifiers are not applicable. In this paper, we propose a new template matching method that is both robust and real-time to multi-class object detections. Firstly, object features are encoded as binary codes based on both quantized gradient intensity and quantized gradient orientation mappings. Then, a two-dimensional index table is constructed. This two-dimensional index table has advantages in effectively organizing relationships between the features from the multi-class templates and their corresponding locations in the templates. For a target image, the features are firstly encoded. Then the object is localized by voting based on the queries of features from the index table. Our experiments on two public data sets demonstrate the high efficiency of our method and the superior performance to the state-of-the-art methods.

Do European blocking events precede North Atlantic Oscillation events?

Using a two-dimensional blocking index, the cause and effect relationship between European blocking (EB) events and North Atlantic Oscillation (NAO) events is investigated. It is shown that the EB event frequency is enhanced over Northern (Southern) Europe for negative (positive) phases of the NAO. Enhanced EB events over Northern Europe precede the establishment of negative phase NAO (NAO−) events, while the enhanced frequency of EB events over Southern Europe lags positive phase NAO (NAO+) events. The physical explanation for why enhanced EB events over Northern (Southern) Europe lead (lag) NAO− (NAO+) events is also provided. It is found that the lead–lag relationship between EB events in different regions and the phase of NAO events can be explained in terms of the different latitudinal distribution of zonal wind associated with the different phases of NAO events. For NAO+ events, the self-maintained eastward displacement of intensified midlatitude positive height anomalies owing to the intensified zonal wind can enhance the frequency of EB events over Southern Europe, thus supporting a standpoint that EB events over Southern Europe lag NAO+ events. Over Northern Europe, EB events lead NAO− events because NAO- events arise from the self-maintained westward migration of intensified blocking anticyclones due to the weakened zonal wind in higher latitudes.

A quick assessment from expert judgements to assist in farmland valuation

Land is the most important agricultural asset, farmland transactions are generally not recurring actions for most buyers and sellers, thus it is often required reliable information from expert judgements. This paper presents a quick asset pricing method under uncertainty, based on the use of two reliability functions, a multidimensional index of characteristics or qualities influencing on the market value and the expert judgments, which overcomes the disadvantages of the valuation method based on two distribution functions for a multidimensional quality index. The usefulness of this method is illustrated through an empirical application on farmland pricing in South-East Spain, using a two-dimensional quality index.

The geometry of distributional preferences and a non-parametric identification approach: The Equality Equivalence Test

This paper proposes a geometric delineation of distributional preference types and a non-parametric approach for their identification in a two-person context. It starts with a small set of assumptions on preferences and shows that this set (i) naturally results in a taxonomy of distributional archetypes that nests all empirically relevant types considered in previous work; and (ii) gives rise to a clean experimental identification procedure – the Equality Equivalence Test – that discriminates between archetypes according to core features of preferences rather than properties of specific modeling variants. As a by-product the test yields a two-dimensional index of preference intensity.

Arbitrary GRIN component fabrication in optically driven diffusive photopolymers.

We introduce a maskless lithography tool and optically-initiated diffusive photopolymer that enable arbitrary two-dimensional gradient index (GRIN) polymer lens profiles. The lithography tool uses a pulse-width modulated deformable mirror device (DMD) to control the 8-bit gray-scale intensity pattern on the material. The custom polymer responds with a self-developing refractive index profile that is non-linear with optical dose. We show that this nonlinear material response can be corrected with pre-compensation of the intensity pattern to yield high fidelity, optically induced index profiles. The process is demonstrated with quadratic, millimeter aperture GRIN lenses, Zernike polynomials and GRIN Fresnel lenses.

Analytical electric field intensity profile in diffused channel waveguides

A novel analytic solution to field distribution is used to calculate the intensity distribution for channel waveguides with a two-dimensional diffusion-type refractive index profile. Composition profiles for the waveguides are obtained by applying the two-dimensional diffusion theory to treat the case of isotropic sideways diffusion. The dependence of the field distributions on the width/depth ratio is studied as an aid to the design of modulators and switches for integrated optics.

Two-dimensional refractive index and stresses profiles of a homogenous bent optical fiber.

We present a significant contribution to the theory of determining the refractive index profile of a bent homogenous optical fiber. In this theory we consider two different processes controlling the index profile variations. The first is the linear index variation due to stress along the bent radius, and the second is the release of this stress on the fiber surface. This release process is considered to have radial dependence on the fiber radius. These considerations enable us to construct the index profile in two dimensions normal to the optical axis, considering the refraction of light rays traversing the fiber. This theory is applied to optical homogenous bent fiber with two bending radii when they are located orthogonal to the light path of the object arm in the holographic setup (like the Mach-Zehnder interferometer). Digital holographic phase shifting interferometry is employed in this study. The recorded phase shifted holograms have been combined, reconstructed, and processed to extract the phase map of the bent optical fiber. A comparison between the extracted optical phase differences and the calculated one indicates that the refractive index profile variation should include the above mentioned two processes, which are considered as a response for stress distribution across the fiber's cross section. The experimentally obtained refractive index profiles provide the stress induced birefringence profile. Thus we are able to present a realistic induced stress profile due to bending.

Damage identification in plates using vibratory power estimated from measured accelerations

Vibratory power is defined as the rate of energy transmitted through a cross section of unit width in a vibrating structure. It is known that the vibratory power is a function of the source and travel path. Therefore the spatial distribution of the vibratory power may contain information on the state of a structure. Vibratory power can be estimated experimentally by measuring accelerations. By combining numerical predictions with experimental measurements the location and severity of damage can be identified. This method has been successfully applied to prismatic beam problems. In the present work, the idea is extended to identifying damage in thin plate problems. To identify damage in thin plates by the proposed vibratory power method, the two-dimensional damage index and damage index ratio are newly introduced. The plate is assumed to be of uniform thickness and damaged in the form of a crack simulated as a straight cut of finite length. The vibratory power of the plate is estimated from frequency response functions to random excitations. First, the proposed method is applied numerically and then verified experimentally. Both numerical and experimental results show the present method can identify not only the location of damage but also its direction. The location and direction can be identified by investigating the damage index, the damage index ratio, and local principal axes of the index peak in the vicinity of the damage. The spatial distribution of the damage index, newly introduced in beam problems, can be considered as a scalar field in plate problems. In the neighborhood of the damage, the damage index has the shape of a semi-ellipsoid or a semi-ovoid, and it is found that the major principal axis corresponds to the direction of the crack. It enables us to identify the damage direction correctly without ambiguity.

Analysis of transient radiative transfer in two-dimensional scattering graded index medium with diffuse energy pulse irradiation

The natural element method (NEM) is extended to solve transient radiative transfer in two-dimensional semitransparent graded index media with energy pulse irradiation diffusely incident on the left boundary. The surfaces of the medium are diffusely reflecting and semitransparent. By using a fully implicit backward differencing scheme to discretize the transient term in the radiative transfer equation and employing the least-squares (LS) weighted residuals approach to discretize the radiative transfer equation, a LSNEM approach is devised. Firstly, LSNEM solutions to transient radiative transfer are validated by comparison with results reported in the literature. Afterward, LSNEM is employed to investigate two-dimensional transient radiative transfer in graded index medium with a refractive index discontinuity at the surfaces. Effects of the optical thickness, scattering phase function and scattering albedo on transmittance and reflectance signals are investigated. Finally, the transient radiative transfer process of the medium subject to square diffuse pulse irradiation train are investigated, and the transient behavior of the radiative energy transport inside the medium with two complex graded index distributions is analyzed.

Sustainable Integrated Process Design and Control for a Continuous-Stirred Tank Reactor System

The objective of this paper is to highlight the use of a two-dimensional (2D) sustainability index in performing a sustainable integrated process design and control (Sustain-IPDC) for a continuous-stirred tank reactor (CSTR) system. Sustain-IPDC for a CSTR system is formulated as a mathematical programming problem and solved by decomposing it into six sequential hierarchical sub-problems: (i) pre-analysis, (ii) design analysis, (iii) controller design analysis, (iv) sustainability analysis, (v) detailed economic analysis, and (vi) final selection and verification. The proposed methodology is applied to the production of cyclohexanone using a CSTR. The results show that the proposed methodology is capable in finding an optimal solution for a CSTR design problem that satisfy design, control, sustainability and economic criteria in an easy and systematic manner.

Spatial-temporal Indexing Research based on Road Network: Improved-MON-tree

Contrary to MON-tree index less than the temporal and spatial indexing methods based on road networks we proposed Improved-MON-tree. The index is divided into two levels and the quad tree grid index at the top of the road network, and the bottom of the two-dimensional Rtree index moving object moving information. In order to support the global trajectory of moving objects query, add a hash structure underlying index structure connected to the moving object information. Verified by experiment, under certain conditions, ImprovedMON-tree than the MON-tree based on edge and routes, has good spatial-temporal window query performance and global trajectory.

Beam path and focusing of flexural Lamb waves within phononic crystal-based acoustic lenses

We describe an analytical approach that allows calculating the trajectories of an elastic beam within a two-dimensional phononic crystal-based gradient index medium. The formalism takes into account the anisotropy along the lines of inclusions where the equi-frequency contours may depart from a circle. We then report on a numerical and experimental study of the focusing of flexural Lamb waves in gradient-indexed phononic crystals. The silicon/air heterostructures that we considered for this work features an index that is obtained through the modulation along one axis of either the diameter of the air inclusions or their spacing. In both cases, numerical and experimental results agree very well. The formalism that we have developed explains well the location, shape and size of the focus in either system.

Measurement of the index of refraction of μm crystals by a confocal laser microscope--potential application for the refractive index mapping of μm scale.

A conventional laser microscope can be used to derive the index of refractivity by the ratio of geometrical height of the transparent platelet to the apparent height of the normal incident light for very small crystals in the wide size range. We demonstrate that the simple method is effective for the samples from 100 μm to 16 μm in size using alkali halide crystals as a model system. The method is also applied for the surface fractured micro-crystals and an inclined crystal with microscopic size regime. Furthermore, we present two-dimensional refractive index mapping as well as two-dimensional height profile for the mixture of three alkali halides, KCl, KI, and NaCl, all are μm in size.

Incremental Value of Three-Dimensional Echocardiography in the Evaluation of Left Ventricular Size in Mitral Regurgitation: A Follow-Up Study after Mitral Valve Surgery

Increased left ventricular (LV) dimensions are an indication for surgery in patients with asymptomatic mitral regurgitation, but M-mode or two-dimensional measurements have known limitations. The aim of this study was to determine the value of three-dimensional echocardiography in predicting postoperative outcomes after mitral surgery. Sixty-seven patients with severe asymptomatic or minimally symptomatic mitral regurgitation (69% men; mean age, 62 ± 13 years) who underwent mitral valve surgery from January 2010 to December 2011 were studied. In addition to standard echocardiography, baseline three-dimensional echocardiography was performed for accurate quantification of LV size. Patients were followed over a median time of 1 month (interquartile range, 0-8 months) for postoperative development of atrial fibrillation or LV dysfunction. A multivariate regression analysis was performed to identify associations with events. Postoperative LV dysfunction developed in 15 patients (22%), and 21 patients (31%) had postoperative atrial fibrillation. There was no association between two-dimensional end-systolic volume index and outcomes (hazard ratio, 1.02; P= .18). Postoperative atrial fibrillation or LV dysfunction was associated with baseline three-dimensional LV end-systolic volume index (hazard ratio, 1.06; 95% confidence interval, 1.04-1.16), independent of age and presence of coronary artery disease. LVESVi ≥ 40 mL/m(2) was the best cutoff value to predict postoperative events (sensitivity, 80%; specificity, 85%). After adding LVESVi to a model containing clinical and echocardiographic parameters, net reclassification improvement was 0.27 (95% confidence interval, 0.25-0.29; P= .024). LVESVi from three-dimensional echocardiography is an independent predictor of postoperative outcomes in patients with severe mitral regurgitation that is incremental to other clinical and echocardiographic variables.

Refractive index profiling of a few-mode fiber from fundamental mode excitation

The fundamental mode of a small-core step-index few-mode fiber, originally designed for single-mode operation at 1310/1550nm, was selectively excited at visible wavelengths from a single-mode fiber by adiabatically tapering the fusion splice. A two-dimensional refractive index profile of the few-mode fiber was reconstructed directly from measured guided mode intensity distribution and its spatial partial derivatives with a modified end-fire coupling method using a differential inverse calculation algorithm, which applies only for single-mode guiding.

Semantic-Preserved Index Constructing for RDF-Based Resource in Structured P2P Network

Resource index constructing method directly influences resource retrieval efficiency in structured P2P network, a new approach to semantic-preserved index constructing for RDF-based resource is proposed. Firstly, each class in resource concept structure is assigned a class ID, RDF-based resource index is constructed by two-dimensional value consisted of class ID; secondly, the mapping from two-dimensional index to one-dimensional routing space of structured P2P network is achieved by Hilbert space filling curve; at last, resource query is realized by embedding the process of searching into the nodes of structured P2P networks and using the data search mechanism of networks. Algorithm analysis shows that this approach supports multidimensional semantic retrieval, resolves the problems that only support exact query based on single key words and the irrelevance between logical location and physical location because of ignoring semantic information, and improves RDF-based resource semantic retrieval efficiency in structured P2P network.

Design Principles of Concentration-Dependent Transcriptome Deviations in Drug-Exposed Differentiating Stem Cells

Information on design principles governing transcriptome changes upon transition from safe to hazardous drug concentrations or from tolerated to cytotoxic drug levels are important for the application of toxicogenomics data in developmental toxicology. Here, we tested the effect of eight concentrations of valproic acid (VPA; 25–1000 μM) in an assay that recapitulates the development of human embryonic stem cells to neuroectoderm. Cells were exposed to the drug during the entire differentiation process, and the number of differentially regulated genes increased continuously over the concentration range from zero to about 3000. We identified overrepresented transcription factor binding sites (TFBS) as well as superordinate cell biological processes, and we developed a gene ontology (GO) activation profiler, as well as a two-dimensional teratogenicity index. Analysis of the transcriptome data set by the above biostatistical and systems biology approaches yielded the following insights: (i) tolerated (≤25 μM), deregulated/teratogenic (150–550 μM), and cytotoxic (≥800 μM) concentrations could be differentiated. (ii) Biological signatures related to the mode of action of VPA, such as protein acetylation, developmental changes, and cell migration, emerged from the teratogenic concentrations range. (iii) Cytotoxicity was not accompanied by signatures of newly emerging canonical cell death/stress indicators, but by catabolism and decreased expression of cell cycle associated genes. (iv) Most, but not all of the GO groups and TFBS seen at the highest concentrations were already overrepresented at 350–450 μM. (v) The teratogenicity index reflected this behavior, and thus differed strongly from cytotoxicity. Our findings suggest the use of the highest noncytotoxic drug concentration for gene array toxicogenomics studies, as higher concentrations possibly yield wrong information on the mode of action, and lower drug levels result in decreased gene expression changes and thus a reduced power of the study.

Self-help Groups as Drivers of Entrepreneurship: Evidence from Karnataka and Odisha States

This paper has conceptualised and measured the graduation of a self-help group member as a two-dimensional index, combining savings and enterprise dimensions, that reflects the ability of SHG members to start their own enterprises/income-generating activities. The study has covered a sample of 240 SHG members drawn from four districts, viz. Khordha and Sambalpur (Odisha) and Dakshina Kannada and Koppal (Karnataka). It was found that about 27 per cent of the SHGs did not have any member having individual savings bank account. The less-developed districts (Sambalpur and Koppal) fared better compared to the developed districts (Khordha and Dakshina Kannada) in terms of savings bank account penetration. The SHG members opened savings bank accounts, mostly for pro-entrepreneurial purposes. They undertook multiple activities ranging from mere wage labour to income-generating/microenterprises. The membership in SHG helped about 40 per cent of the people in taking up two or more additional activities than before. Farming followed by wage labour have been found the primary activities among SHG members. The tendency for taking up additional activities was higher among members from less-developed districts. The members with higher accumulated savings and possessing a mobile phone or belonging to younger groups have shown higher probability of going for additional activity. The paper has identified personal factors, SHG-related aspects and environment-related factors that helped the graduation process. Savings have shown positive influence on graduation index. However, borrowings did not emerge as a positive factor behind graduation. Nor it stimulated members to take up additional activities. However, using loan for non-consumption use has encouraged higher level of graduation. The paper has suggested scale, scope, convergence of efforts by different agencies and training as important aspects for consideration and has recommended to start a registry to avoid duplication of efforts.