Effective Index Method Research Articles

Enhancing Database Query Performance: Analysis of Indexing Techniques

The need to enhance query performance in databases within the contemporary information environment is crucial for ensuring efficient operations across various domains. This paper is dedicated to an analysis of database indexing techniques aimed at understanding their impact on query performance and efficiency. It meticulously examines various types of indexes, including B-trees, hash tables, and textual indexes, analyzing their advantages and limitations. The investigation into the influence of these techniques on query execution time reveals that performance depends on various factors such as query complexity and data volume. Special attention is given to selecting the optimal index type based on specific database needs and characteristics. The research underscores the importance of considering data volume and database structure in choosing effective indexing methods. Additionally, the advantages and disadvantages of different indexing techniques are scrutinized, taking into account their impact on query execution speed and efficiency. Of the study indicate that the correct selection and utilization of appropriate indexing strategies can significantly enhance the performance of database management systems, providing swift and efficient access to information for users. Ultimately, this work makes a significant contribution to understanding and practically applying indexing techniques to improve query performance in databases.

Effect of The Ratio of Purple Sweet Potato Flour and Rice Crust Flour on The Physical, Chemical, and Sensory Properties of High-Fiber Snack Bar

Dietary fiber, an indigestible component of plants, offers significant health benefits for humans. Creating a high-fiber snack bar can be a substitute for meeting daily requirements for dietary fiber. This research aimed to create snack bar products utilizing locally sourced ingredients, specifically rice crust flour and purple sweet potato flour, with the goal of optimizing the utilization of local food resources and enhancing the diversity of Indonesian cuisine. This study aimed to investigate how the proportion of purple sweet potato flour and rice crust flour influenced the chemical, physical, and sensory characteristics of the high-fiber snack bars that were created. The proportions of purple sweet potato flour to rice crust flour differed across the four snack bar formulas: FI (100%:0%), F2 (90%:10%), F3 (80%:20%), and F4 (70%:30%). The effectiveness index method was employed to determine the optimal formulation for the snack bar. The results indicated that lowering the proportion of purple sweet potato flour would enhance the firmness and color of the snack bar. The dietary fiber content (%db) of each formula was as follows: F1 (18.92 ± 1.43%), F2 (18.33 ± 0.79%), F3 (18.56 ± 2.73%), and F4 (19.48 ± 0.40%). The sensory test results showed a direct correlation between the panelists' preference level and the decrease in the proportion of purple sweet potato flour. Formula F4, consisting of a 70% proportion of purple sweet potato flour and a 30% proportion of rice crust flour, is the optimal formula for creating a snack bar.

On characteristic behavior and flattened chromatic dispersion properties of bent photonic crystal fibers

Abstract In this paper by using modified scalar effective index method, first effective refractive index of straight and bent photonic crystal fibers are determined and then propagation parameters, such as chromatic dispersions for different structural designs of PCF, are obtained. By changing the values of affecting parameters in the bent PCF, such as different bent radius, distance between air holes Λ $\Lambda $ and air-filling factor d / Λ , $d/\Lambda ,$ the chromatic dispersion is determined in terms of propagating wavelengths. The obtained results of bent PCF are compared with the results of straight PCF. The results of the present paper might be useful in designing optical devices and sensing systems.

Inverse Effective Index Method for Two-Dimensional Simulations of Photonic Components

Inverse Effective Index Method for Two-Dimensional Simulations of Photonic Components

Process of making muffin from modified sweet potato flour made from sustainable raw material based Indonesian local resources

Modified sweet potato flour is sweet potato flour that has been enhanced to maintain and improve its quality, thereby reducing the overall consumption of sweet potato flour in Indonesia. Muffins, being a type of quick bread that requires only a small amount of gluten, are highly suitable for use with modified sweet potato flour. This research was carried out in two stages: Stage I involved the modification of sweet potato flour, and stage II consisted of formulating a mixture of wheat flour and modified sweet potato flour. The research employs a non-factorial Completely Randomized Design (CRD) for both of these two stages and the determine of the best treatments are conducted using De Garmo effectiveness index method. The modified flour (annealing, instant yeast fermentation, LAB fermentation, and acetic acid) was analyzed for various quality parameters. Once the best method for modifying sweet potato flour was determined, the second stage involved the preparation of muffins. The muffin (100:0, 75:25, 50:50, 25:75, and 0:100) were also analyzed for various quality. The final results indicated that the J3 treatment (LAB fermentation) was the most effective for modifying the flour, and the F2 treatment (75:25 ratio) was the best formulation for muffins.

AN IMPROVED INDEXING METHOD FOR QUERYING BIG XML FILES

The exponential growth of bioinformatics in the healthcare domain has revolutionized our understanding of DNA, proteins, and other biomolecular entities. This remarkable progress has generated an overwhelming volume of data, necessitating big data technologies for efficient storage and indexing. While big data technologies like Hadoop offer substantial support for big XML file storage, the challenges of indexing data sizes and XPath query performance persist. To enhance the efficiency of XPath queries and address the data size problem, a novel approach that is derived from the spatial indexing method of the R-tre family. The proposed method is to modify the structure of leaf nodes in the indexing tree to preserve XML-sibling connections. Then, new algorithms for constructing the new tree structure and processing sibling queries better are introduced. Experimental results demonstrate the superior efficiency of sibling XPath queries with reduced data sizes for indexing, while other XPath queries exhibit notable performance improvements. This research contributes to the development of more effective indexing methods for managing and querying large XML datasets in bioinformatics applications, ultimately advancing biomedical research and healthcare initiatives.

A Semi-Analytical Method for the S-Parameter Calculations of an N × M Multimode Interference Coupler

A semi-analytical method for the S-parameter calculations of an N×M multimode interference coupler (MMI coupler) is presented. The proposed semi-analytical method is based on the mode decomposition and utilizes an effective index method to approximate the channel waveguide using an equivalent slab waveguide whose modes are described by exact analytic expressions. In comparison to the commonly used beam propagation method (BPM) and finite difference time domain method, which require significant time and computational resources, the proposed method accelerates the design process of photonic integrated circuits and basic building blocks such as an MMI coupler. The simulation results obtained using the developed method and the BPM were compared and showed very similar outcomes for different topologies of the MMI coupler. The key advantage of the proposed semi-analytical method over other analytical models is its ability to accurately simulate MMI couplers with an arbitrary position and number of input and output waveguides. In addition, this method can be extended using the theory of local coupled modes by taking into account the reflections from the end face of the MMI box.

Antioxidant Activity and Organoleptic Quality of Crackers with Differences in the Addition of Black Glutinous Tape and Baking Powder

Tapioca flour-based crackers are a popular dry snack in Indonesia, characterized by their high starch content. However, recent developments have focused on creating crackers that are not only tasty but also have high nutritional value. One way to achieve this is by fortifying crackers with fermented products like black glutinous rice tape. This ingredient is known for its excellent nutrition and high antioxidant content, making it a healthy addition to crackers. The expansion of the volume of crackers is the primary factor that affects the crispness and quality of the crackers. This study aims to determine the proportion of the addition of black glutinous rice tape and baking powder concentration to the characteristics of crackers and determine the best crackers that can produce good quality and are acceptable in terms of sensory. The research design was a randomized complete block design with two factors. The first factor of black glutinous rice tape percentage (20, 30, 40%) and the second factor of baking powder concentration (0.1, 0.2, 0.3%) repeated three times resulted in 27 attempts. The ANOVA two-way statistics was utilized by the researchers to evaluate the chemical data, followed by the Tukey test to detect any significant differences among the treatments. Moreover, they employed Friedman's method to carry out organoleptic testing. The Effectiveness Index method identified the best treatment for chemical and organoleptic analysis, which was T3B2 (0.2% baking powder and 40% black glutinous rice tape). This treatment resulted in an antioxidant activity of 141.15 ppm, a water content of 9.05%, and an ash content of 1.71%. In addition, the organoleptic scores for color, aroma, taste, and texture were rated 4.66, 4.66, 3.40, and 3.70, respectively (3=least liked, 4= liked).

Proposal of a novel analytical method for simultaneous ultra-broadband and ultrashort laser pulses generation in photonic crystal fibers with optimized manufacturing process

In this paper, a novel method for simultaneous ultra-broadband and ultrashort femtosecond laser pulse generation in silica photonic crystal fibers is investigated analytically using the fully vectorial effective index method (FVEIM). By reducing the impact of fifth and lower-order dispersions, the method produces narrower laser pulses and wider supercontinuum using a fixed soliton order over a specific distance of the fiber. Additionally, the larger effective areas utilized in this approach make the manufacturing process simpler compared to other samples. These simultaneous features represent the primary innovations of this study.

Engineering in the Production of Crystal Coconut Sugar Enriched with Vitamin A and its Preference Tests for Consumers

Coconut sugar is a food product that has the potential to be fortified with Vitamin A. This study aims to assess the quality of crystalline coconut sugar with vitamin A and test its preference for consumers. The experimental design used Split Plot Design with two treatment factors and 4 replications. The first treatment as the Main Plot (Main Plot) is the type of raw material for crystalline coconut sugar, which consists of 2 variations, namely: M1 = pure sap, and M2 = printed coconut sugar + 5% granulated sugar. The second treatment as a sub-plot was the proportion between palm oil as a solvent and carrots as a source of carotene (Vitamin A), which consisted of 3 variations, namely: S1= 1 : 1 (v/b), S2 = 1 : 2 (v/b), and S3= 2 : 1 (v/b). Physicochemical data were analyzed by F test and followed by 5% DMRT test, while organoleptic properties data were analyzed by Friedman test and followed by multiple comparison test. The best treatment was analyzed by the effectiveness index method. The results showed that a good raw material for producing crystalline coconut sugar with low reducing sugar content and high sucrose content was pure coconut sap. The proportion between palm oil and carrots which can produce crystalline coconut sugar with high levels of carotene (pro vitamin A) is 1 : 2 (v/b). The treatment combination that can produce crystalline coconut sugar with vitamin A with quality according to SNI-SII No.0268-85 is the treatment of the type of raw material for crystalline coconut sugar from pure coconut sap and the proportion of palm oil as a solvent with carrots as a source of carotene 1 : 2 ( v/b). This combination of treatments produced crystalline coconut sugar with physicochemical and organoleptic properties as follows: carotene content of 9.015 mg/100g of material or the equivalent of 752 RE (Retinol equivalent), water content of 3.617 percent, total sugar content of 81.071 percent, sucrose content of 75.627 percent, sugar content 5.434 percent reduction, 0.753 percent ash content and 0.197 percent water insoluble material content, "very smooth" texture, "creamy" color, "strong" coconut aroma, "not felt" carrot unpleasant smell and level of consumer acceptance (preference) "like".

How bending deformation affects the performance of polarization converters based on slot waveguides

Polarization is an important characteristic of light and plays a critical role in many natural and industrial processes. In this paper, we present an optical gradient force actuated polarization converter based on a slot waveguide, which can convert linearly polarized light into circularly polarized light. The working principle of the presented polarization converter is that optical gradient forces deform the slot waveguide to adjust its birefringence, thus yielding a desired phase shift between two orthogonal components of light. An optomechanical model with all possible mechanical boundaries is developed to solve the bending deformation of polarization converters. The effective index method and dispersion relation method are used for the calculation of birefringence and optical gradient forces, respectively. The influences of the width of waveguides and the initial width of the slot on the working performance of polarization converters are discussed. It is found that these influences are independent of the mechanical boundaries. An empirical formula for describing the relation between the working power and length of polarization converters is given. This empirical formula may be helpful when designing such polarization converters.

HR-Index: An Effective Index Method for Historical Reachability Queries over Evolving Graphs

Reachability query is a fundamental problem and has been well studied on static graphs. However, in the real world, the graphs are not static but always evolving over time. In this paper, we study the problem of historical reachability query on evolving graphs. We propose a novel index, named HR-Index, which integrates complete and correct historical reachability information of the evolving graph. A historical reachability query on an evolving graph can be converted into a static reachability query on its HR-Index and thus query efficiency can be improved significantly. We also propose two optimization techniques to reduce the size of HR-Index effectively. We confirm the effectiveness and efficiency of our method through conducting extensive experiments on real-life datasets. Experimental results show both vertex and edge size of HR-Index are far smaller than that of the evolving graphs and our method has at least an order of magnitude improvement in time and space efficiency compared to the state-of-the-art method.

Design and analysis of 1:2 line optical decoder based on linear optics

In this paper, a simple design of all-optical photonic crystal (PhC) based 1:2 line decoder has been proposed and its operating principle is based on light beam interference. The designed structure has a hexagonal arrangement of air holes in Si substrate with a finite slab height. In our proposed structure, different path lengths have been made so that the light beams should interact out of phase. Effective refractive index method has been adopted to reduce the simulation time. The Finite Difference Time Domain (FDTD) and Plane Wave Expansion (PWE) methods have been applied to evaluate the proposed structures. The required footprint area for proposed device is reported as 215 µm2. Minimum contrast ratio between the logic states of “1” and “0” is obtained as 10 dB. This device is designed based on solely linear optical phenomena in a holes-in-slab PhC structure. Therefore, mechanically stabled, ultra-compact design and simple working mechanism of the proposed optical decoder can be a potential candidate for future generation Photonic Integrated Circuits (PICs).

Applicability of the Effective Index Method for the Simulation of X-Cut LiNbO3 Waveguides

Photonic integrated circuits (PIC) find applications in the fields of microwaves, telecoms and sensing. Generally, PICs are fabricated on a base of isotropic materials such as SOI, Si3N4, etc. However, for some applications, anisotropic substrates such as LiNbO3 are used. A thin film of LiNbO3 on an insulator (LNOI) is a promising material platform for complex high-speed PICs. The design and simulation of PICs on anisotropic materials should be performed using rigorous numerical methods based on Maxwell’s equations. These methods are characterized by long calculation times for one simulation iteration. Since a large number of simulation iterations are performed during the PIC design, simulation methods based on approximations should be used. The effective index method (EIM) is an approximation-based method and is widely applied for simulations of isotropic waveguides. In this study, the applicability of EIM for simulations of anisotropic waveguides is analyzed. The results obtained by EIM are compared with the calculation results of a rigorous finite-difference frequency-domain (FDFD) method for evaluation of the EIM’s applicability limits. In addition, radiation losses in waveguides with rough sidewalls are estimated using the Payne–Lacey model and EIM. The results demonstrate the applicability of EIM for the simulation of anisotropic LNOI-based waveguides with cross-section parameters specified in this paper.

Using Hocker and Burns numerical method to analyze the dispersion properties of a planar waveguide with an exponentially graded-index core layer for s-polarized light

Although not realistic, the theory of step-index waveguide has been discussed in most published works. Electric and magnetic fields can be written as well-known functions such as exponential, sine and cosine functions. However, the index distribution of the most practical waveguides is better described as graded. Despite certain similarities, step-index and graded-index waveguide structures also have considerable differences. The characteristic equation of s-polarized wave propagating in a planar waveguide with an exponentially graded-index thin core layer is examined in this work using the Hocker and Burns numerical approach. This method utilizes the effective index method of analyzing waveguides with 2D confinement. It was efficiently applied to problems of channel waveguides formed by diffusion. The technique depends on finding the phase shift of the curved optical path in the graded index zone as stacked infinite thin layers. Three factors contribute to the total transverse phase shift: (1) film-cladding interface phase delay, (2) film-substrate interface phase delay, and (3) phase delay caused by the zigzag optical path of the guiding film. The findings revealed the following intriguing observations. The dispersion curves of the graded-index waveguide structure are in the normal shape in which the generalized guide index (GeGI) increases with the rise of the normalized frequency. At high values of the normalized frequency, the GeGI displays less dependence on it. The dispersion curves show cut-off thicknesses which increase for higher asymmetry measure values. A comparison between graded-index and step-index waveguide structures is carried out.

Electro-stimulation of tofu wastewater for the production of single cell protein from various microorganisms

Tofu wastewater can be utilized as a substrate for microorganisms that produce single-cell proteins (SCPs). Because different microorganisms have different cellular components, the composition of SCPs varies. Electro-stimulation has the potential to speed up fermentation and increase product yield. The goal of this study was to find the best way to produce SCPs from Aspergillus awamori, Rhizopus oryzae, and Saccharomyces cerevisiae in the tofu wastewater substrate using electro-stimulation. The experimental method was used in the study, the data were analyzed using independent t-test statistical analysis, and the best treatment was identified using the effective index method. This treatment consisted of producing SCP with electro-stimulation of −1.5 V and without electro-stimulation for 72 h for the yeast and 96 h for the mold at 25 °C in tofu wastewater that had already been conditioned to a pH of 5. The parameters measured included measurement of population of microorganism, change in pH, dry biomass weight, carbohydrate content, and protein content. Electro-stimulation reduced the optimum fermentation time of A. awamori SCP from 56 to 32 h, resulting in 0.0406 g/50 mL of dry biomass, 30.09% carbohydrate content, and 6.86% protein content. Meanwhile, the optimal fermentation time on R. oryzae and S. cerevisiae were not accelerated by electro-stimulation. The best treatment was A. awamori without electro-stimulation, which produced 0.0931 g/50 mL of dry biomass, 20.29% carbohydrate, and 7.55% protein.

Machine learning assisted cancer cell detection using strip waveguide Bragg gratings

An early cancer diagnosis has become necessary in the medical domain as it can facilitate a timely and appropriate treatment, providing for the clinical management of patients. This work proposes a rapid and inexpensive label-free bio-sensing platform based on Waveguide Bragg Gratings for cancer detection. The refractive index values of cancer cells are different from normal cells, which provide a different reflection spectrum when the sample is placed on the functionalized surface of the waveguide grating structure. We combine simulations from the effective index method, finite element method, and Transfer Matrix method of the Grating structure to optimize the sensing structure and employ a neural network model to predict whether a sample contains cancerous cells. The machine learning model provides excellent accuracy for high-resolution interrogator data, and the accuracy falls below 95% only when the resolution of the interrogator is taken as 0.9 nm, thereby eliminating the need for an expensive high-resolution optical Interrogator system. This, combined with the mass-scale production capability of the waveguide Bragg gratings using standard CMOS technology, paves the way towards combining nano-scale optical biosensing platforms and machine learning-based optimization techniques for early and low-cost label-free cancer detections.

Transverse Photonic Crystal Mode Engineering for Broad-Area Semiconductor Lasers With Narrow-Divergence Angles

Broad-area semiconductor lasers, coupled with asymmetric transverse photonic crystals (TPCs), are designed by the effective index method and the transfer matrix method. Due to the propagation constant of the fundamental mode lying in the forbidden band of the TPCs, but those of the high-order modes lying in the allowed band of the TPCs, the fundamental mode is mainly concentrated in the active ridge waveguide, while all the high-order modes extend into the lossy TPCs on both sides of the active ridge waveguide. Therefore, the fundamental mode possesses larger optical confinement factor than those of the high-order modes, and reaches the lasing threshold more easily, which is demonstrated by the single-lobe horizontal far-field pattern of the TPC broad-area laser under an injection current of 0.3 A near the threshold. The proposed TPC broad-area laser provides a new strategy of designing broad-area semiconductor lasers with narrow divergence angles.

Determination of the nonlinear thermo-optic coefficient of silicon nitride and oxide using an effective index method.

There is little literature characterizing the temperature-dependent thermo-optic coefficient (TOC) for low pressure chemical vapor deposition (LPCVD) silicon nitride or plasma enhanced chemical vapor deposition (PECVD) silicon dioxide at temperatures above 300 K. In this study, we characterize these material TOC's from approximately 300-460 K, yielding values of (2.51 ± 0.08) · 10-5K-1 for silicon nitride and (5.67 ± 0.53) · 10-6K-1 for silicon oxide at room temperature (300 K). We use a simplified experimental setup and apply an analytical technique to account for thermal expansion during the extraction process. We also show that the waveguide geometry and method used to determine the resonant wavelength have a substantial impact on the precision of our results, a fact which can be used to improve the precision of numerous ring resonator index sensing experiments.

Generation of Parabolic pulse by nonlinear pulse reshaping inside a Silicon on Insulator (SOI) Waveguide

In recent times, silicon photonics attracts a lot of attraction of researchers. It is the technology that converts many functions of the circuit on the thumb-size chip. Nowadays, various types of technology platforms are being used to design photonic integrated circuits using various materials such as high index glass, semiconductors, polymers, and silicon. In our work, we have used silicon to design rectangular silicon on Insulator (SOI) buried waveguide. This type of waveguide has shown great potential in the field of pulse reshaping. We have used the effective index method for the calculation of group velocity dispersion and nonlinearity. Though the two-photon absorption and free-carrier generation contribute significantly to loss parameters, the highly nonlinear buried waveguide is found to be capable of reshaping super-Gaussian pulse input into a parabolic shape. Moreover, the values of input chirp, pulse width, and peak power are further optimized for the generation of a high-quality parabolic pulse at shorter lengths. The length required for pulse reshaping is much less when compared to optical fibers. Thus, our design waveguide has potential in the domain of pulse generation, signal processing, and many more.