Miracle-dz/UniFAR-FTUs huggingface dataset:
Analysis of erbium-doped waveguide amplifiers by a full-vectorial finite-element method

Erbium-doped waveguide amplifiers are analyzed by solving numerically Maxwell equations and propagation-rate equations of a homogeneous three-level laser medium. In these new devices, the large refractive index changes and the complex geometries of the waveguides require an electromagnetic analysis which has to incorporate vectorial effects. A full-vectorial finite-element code is used to account for the effect of spatial mode distributions, and an iterative procedure, based on the Runge-Kutta algorithm, makes it possible to compute both gain and amplified spontaneous emission spectra with standard rate-equations and propagation equations. The method proposed allows one to model waveguide structures of practical interest and to identify an optimum configuration with regard to polarization effects on the signal gain, maximum gain, pumping efficiency and noise characteristics. Numerical results are reported regarding rib, channel, and thin-film erbium-doped silica waveguide amplifiers. >
A Prototype System for Early-Stage Breast Cancer Detection

The early detection of breast cancer is very important. The final goal of this study is to develop an inexpensive portable device for simply detecting the existence of breast cancer using microwaves. In this study, we proposed a detection algorithm and the system configuration of such a device. The feasibility of the proposed method was investigated by numerical simulation and actual measurement. A prototype sensing module was fabricated, and the measurement results for tumor phantoms were presented. The measurement results showed that the prototype sensing module worked well, and the simulation results revealed that the detection rate of the device could be about 60% for a 4 mm tumor and almost 100% for a 6 mm tumor. The proposed device can be used for the self-diagnosis of breast cancer. Further study is required to reduce the size of the sensing module.
Design a linear irregular Fresnel lens to thin an LED-based direct-type backlight module and improve the illuminance and uniformity of LCD panel

We propose a Linear Irregular Fresnel Lens (denoted as LIFL) to replace the diffusion sheet and prism sheet in a rectangular LED-based Direct-type Backlight Module. The aim is to improve the illuminance and uniformity of LCD panel, as well as to reduce the cost of Backlight Module and make the Module thin. Here "Linear" means the grooves of a Fresnel lens are arranged linearly and "irregular" means that the sequence of all groove angles is not increasing or decreasing. To let the designed LIFL possess good effects of light ray guiding, two layers of LIFLs are needed. The first layer LIFL consists of x-axis grooves, whereas the second layer LIFL consists of y-axis grooves to guide all light rays guided by the first layer LIFL. The groove angles of the designed LIFL are evolved by a Genetic Algorithm which is developed in terms of the performance requirement on illuminance and uniformity of LCD panel in a rectangular LED-based Direct-type Backlight Module. In this paper, we will simulate a simple fifteen-LED Direct-type Backlight Module to demonstrate the performances on illuminance and uniformity of the designed LIFL.
Isosceles triangular unequal power divider

A three‐port two‐way isosceles triangular microstrip unequal power divider configuration has been proposed for broadband and direct coupled applications. An isosceles triangular microstrip patch is fed at the vertex of one of its equal angles and unequal power division has been obtained at the other two vertices. Unequal power division from –6.2 to –15.9 dB has been achieved by varying the height of the triangular patch. This configuration has been analyzed using transmission line model and commercially available ie3d software, followed by experimental verifications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:254–258, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27314
System conception of intellectual monitoring of online user's activity on the example of university department

An approach for monitoring Internet user’s activity of computer networks based on the Data Mining technology is offered. Within this conception an investigation on the example of the university department is performed. Justification and selection of the informative indicators describing an Internet user and his network behavior are done. Using the factor analysis its reduction is performed. The existence of a natural segmentation of users in a space of three latent orthogonal factors is proved. The model of deviance analysis for users’ segments by creation of confidence ellipsoids in a space of three mentioned above factors is proposed. Testing simulation on the example of the university department is conducted.
Internet Commerce for Small Businesses

Online buying is expected to hit $4.8 billion in 1998, and is estimated to reach the $12 billion mark by the end of this century. This is one of the very few places where small businesses are able to effectively compete with their bigger rivals. All sites on the Internet are equal, and the small businesses can launch complex sales programs and implement effective globalization strategies on the Internet just like the bigger companies. However, certain guidelines must be observed by owners of small businesses in order to enjoy the benefits of the Internet commerce. This study provides some practical implementation strategies to work at each stage of the Web site life cycle in an effort to help small businesses implement successful Internet commerce programs.
Index Optimization and Integrated Loop Control of Heating Furnaces Based on Modern Control Theory

The furnace temperature control plays an important role in the rolling process, it affects the quality of steel and energy consumption directly. It is clear that furnace temperature change is multivariable, nonlinear, coupling, great inertia and pure lag and the complex industrial process of furnace control should be optimized. In this paper, a intelligent temperature control system was designed which has a two-layer structure includes optimizing and controlling. The control system is successfully applied to a steel company in medium plate product processes, and achieved good effects. The controllability can be applied to similar industrial furnaces, and has a wide application prospect.
Constant frequency torque and flux controllers for direct torque control of induction machines

This paper proposed a simple solution to the variable switching frequency and high torque ripple problems encountered in hysteresis-based DTC drives. The method replaces the hysteresis-based controllers with fixed switching controllers, which operate based on the comparison between the error signals and the triangular waveforms. Implementation of these controllers using digital circuits is highly suitable since they only require comparisons of waveforms rather than calculations of duty cycles or voltage vectors. Modeling and simulation of the DTC drives using these simple controllers are presented and the results show that they are capable of reducing the torque ripples significantly.
Broad-Band Isolators and Variable Attenuators for Millimeter Wavelengths

A longitudinally magnetized rod of ferrite has been used as a dielectric waveguide which provides Faraday rotation independent of frequency in the band from 50 to 60 kMc. This rotator has been incorporated into broad-band isolators with forward losses of 1 db and reverse losses greater than 30 db with return losses of approximately 20 db over the band. It has also been used in a variable attenuator with a minimum loss of 1 db and a maximum loss greater than 30 db which is essentially constant over the band. Advantages of this type of rotator at millimeter wavelengths include bandwidths in excess of 20 per cent, low field requirements (25-50 /spl oelig/), relatively large dimensions, the use of common ferrites, and the absence of conducting waveguide walls which permits rapid switching of the control field. The last feature has been utilized in an automatic power leveling system capable of removing variations of several kc frequency content from the swept output of a millimeter wave BWO.
Optimal Layout of Early Warning Detection Stations for Water Distribution Systems Security

Deliberate contamination is generally viewed as the most serious potential terrorist threat to water systems. Chemical or biological agents could spread throughout a distribution system and result in sickness or death among the people drinking the water. Since September 11, 2001 the U.S. Environmental Protection Agency's water protection task force and regional offices have initiated massive actions to improve the security of the drinking water infrastructure. A methodology is presented for finding the optimal layout of an early warning detection system ~EWDS! The detection system is comprised of a set of monitoring stations aimed at capturing deliberate external terrorist hazard intrusions through water distribution system nodes—sources, tanks, and consumers. The optimization considers extended period unsteady hydraulics and water quality conditions for a given defensive level of service to the public, defined as a maximum volume of polluted water exposure at a concentration higher than a minimum hazard level. Such a scheme provides an EWDS for a deliberate terrorist external hazard intrusion, as well as for accidental contamination entries under unsteady conditions—a problem that currently has not been solved. The methodology is cast in a genetic algorithm framework for integration with EPANET and is demonstrated through two example applications. DOI: 10.1061/~ASCE! 0733-9496~2004! 130:5~377! CE Database subject headings: Water distribution; Monitoring; Optimization; Evolutionary computation; Water quality; Security; Terrorism.
WindGMMN: Scenario Forecasting for Wind Power Using Generative Moment Matching Networks

With the increasing penetration of wind power generation, the fluctuating and intermittent behavior of wind power poses huge challenges to the operation and planning of distribution networks. A popular way to mitigate these challenges is to provide a group of possible wind power forecasting scenarios instead of depending on deterministic point forecasting values, so that system operators can consider the uncertainties. This letter proposes a novel WindGMMN method for wind power scenario forecasting, in which necessary modifications are made on the generative moment matching network (GMMN), and an optimization strategy is designed to find a series of wind power scenarios with similar shapes, probability distributions, and temporal correlations as potential scenarios. Simulations and analyses were performed on a public dataset with 2190 wind power generation curves and their corresponding meteorological features. The results show that the proposed WindGMMN outperforms popular baselines (e.g., variational auto-encoders and generative adversarial networks) for scenario forecasting of wind power, without any restrictions on the time horizon (e.g., times ranging from 10 min to 24 h).
Minimization of the DC current ripple of a three-phase buck-boost PWM unity power factor rectifier

The modulation of a novel three-phase three-switch buck-type unity power factor rectifier with integrated DC/DC boost converter output stage is optimized concerning the ripple amplitude of the buck-boost inductor current. This is achieved by coordination of the switching operation of the buck input stage and of the boost output stage. A comparative evaluation of different modulation schemes does identify a modulation scheme which simultaneously does provide minimum DC current ripple and minimum input filter capacitor voltage ripple at minimum switching losses and/or maximum pulse frequency. All theoretical considerations are for operation in a wide input voltage range and are verified by simulations and by measurements on a DSP-controlled 5 k W prototype of the system.
PHYSICAL MODELS AND LABORATORY TECHNIQUES IN COASTAL ENGINEERING

Laboratory physical models are a valuable tool for coastal engineers. Physical models help us to understand the complex hydrodynamic processes occurring in the nearshore zone and they provide reliable and economic engineering design solutions.This book is about the art and science of physical modeling as applied in coastal engineering. The aim of the book is to consolidate and synthesize into a single text much of the knowledge about physical modeling that has been developed worldwide.This book was written to serve as a graduate-level text for a course in physical modeling or as a reference text for engineers and researchers engaged in physical modeling and laboratory experimentation. The first three chapters serve as an introduction to similitude and physical models, covering topics such as advantages and disadvantages of physical models, systems of units, dimensional analysis, types of similitude and various hydraulic similitude criteria applicable to coastal engineering models.Practical application of similitude principles to coastal engineering studies is covered in Chapter 4 (Hydrodynamic Models), Chapter 5 (Coastal Structure Models) and Chapter 6 (Sediment Transport Models). These chapters develop the appropriate similitude criteria, discuss inherent laboratory and scale effects and overview the technical literature pertaining to these types of models. The final two chapters focus on the related subjects of laboratory wave generation (Chapter 7) and measurement and analysis techniques (Chapter 8).
A Collaborative Optimization Model for Ground Taxi Based on Aircraft Priority

Large hub airports have gradually become the “bottleneck” of the air transport network. To alleviate the “bottleneck” effect, optimizing the taxi scheduling is one of the solutions. This paper establishes a scheduling optimization model by introducing priority of aircraft under collaborative decision-making mechanism, and a genetic algorithm is designed to verify the scheduling model by simulating. Optimization results show that the reliability of the model and the adjusted genetic algorithm have a high efficiency. The taxiing time decreases by 2.26% when compared with an empirical method and the flights with higher priorities are assigned better taxi routes. It has great significance in reducing flight delays and cost of operation.
Let’s Go for a Tour…. The Smart Way

Pandemics are not new, and like other crises and disasters, they can have long-term consequences for individuals, businesses, communities, and countries. This Covid-19 pandemic has also affected tourism industry all over the world, having to face challenges to sustain in the international market. Hence, to address limitations to travel, smart tourism technology is seen as rapidly advancing and opening new potential for tourism growth. With the pandemic highly impacting the tourism industry globally, tourist managers and operators have to resort to the use of smart technology to ensure the sustenance of the tourist industry. As such, smart tourism technology is now being practiced by many tour operators to attract visitors and enhance their trip experience. Many tourism-related firms have implemented a variety of smart technologies to promote and market their locations, where Malaysia is of no exception. In order to explore innovative ways to create memorable experiences for visitors, Malaysia has also taken steps to embrace this technology. The site on “Animal Park” reflected as a zoo is one of the examples that has implemented live virtual tour in order to attract visitors to at least experience “visiting” the zoo by seeing the view of the zoo through virtual technology. Differences in visitor experiences need to be captured to create impact on smart tourism experiences. Thus, this study is to measure the visitor’s satisfaction to the smart tourism technology experiences (informativeness, accessibility, interactivity, personalization, and security) that have been practiced in Malaysia’s virtual animal park. T he anticipated study will assist destination managers and local authorities in gaining information on smart tourism technology and understand the visitor’s satisfaction and their experience in live virtual tours implemented via smart tourism technology. This is in line with the National Tourism Policy (NTP) launched in December 2020 to ensure the continuity of the country’s tourism industry and make Malaysia a preferred tourist destination globally.
Image Mosaic Using SIFT for Bridge Cable Surface Flaw Detection

A machine vision system is developed to detect the cable surface damage of cable-stayed bridge. In the system, four cameras are employed to acquire images around the cable surface. So the same one defect may be split into several images. Image mosaic had to be done to obtain a complete defect image for further process. The feature of cable surface image is simple and its illumination is heterogeneous. So the Scale Invariant Feature Transform (SIFT) feature matching algorithm is suitable for the image mosaic. Firstly, cable surface images should be preprocessed. Secondly, the SIFT algorithm achieves the detection, extraction, description and matching of feature points for defect images. Finally, image fusion is implemented to acquire the integrated image and a complete defect will be showed in the image. Experimental results show that using SIFT for the cable defect image mosaic has good effect on improving the detection accuracy and integrity for cable surface defects.
Evaluation of patella fractures managed by augmented cannulated cancellous screw fixation: A prospective study

Patella is an important part of the extensor mechanism of the knee hence proper management of patellar fractures is necessary to prevent any complications. We conducted this study to evaluate cannulated cancellous screws as a modality of fixation for transverse fractures of patella. 63 patients of patella fracture were admitted, operated and followed who were managed by the above mentioned technique and based on our observation and results we recommend augmented cannulated cancellous screw as a better implant as compared to other contemporary implants for patella fracture fixation.
Field Decorrelation and Isolation Improvement in an MIMO Antenna Using an All-Dielectric Device Based on Transformation Electromagnetics

This work presents a new technique for enhancing the performance of a multiple-input multiple-output (MIMO) antenna by improving its correlation coefficient ρ. A broadband dielectric structure is designed using the transformation electromagnetics (TE) concept to decorrelate the fields of closely placed radiating elements of an MIMO antenna, thereby decreasing ρ and mutual coupling. The desired properties of the broadband dielectric wave tilting structure (DWTS) are determined by using quasi-conformal transformation electromagnetics (QCTE). Next, the permittivity profile of the DWTS is realized by employing air-hole technology, which is based on the effective medium theory, and the DWTS is fabricated using the additive manufacturing (3D printing) technique. The effectiveness of the proposed technique is verified by designing two-element patch-based MIMO antenna prototypes operating at 3 GHz, 5 GHz, and 7 GHz, respectively. The proposed technique helped to reduce the correlation coefficient ρ in the range of 37% to 99% in the respective operating bandwidth of each MIMO antenna, thereby, in each case, improving the isolation between antenna elements by better than 3 dB, which is an excellent performance.
Service management in housing refurbishment: a theoretical approach

It is unusual to find that housing refurbishment projects have been undertaken with a clear focus on customer orientation directed towards the tenants, or owners of cooperative flats or condominiums. Only recently have researchers in construction management begun to look closer at the relationship between contractors and customers. To assess the scope for customer orientation in the refurbishment industry, current thinking in service management is reviewed here in an attempt to identify principles with implications for housing refurbishment. There is a consensus among service management investigators that services are intangible; other often mentioned characteristics are heterogeneity, perishability, and the inseparability of production and consumption. Except for inseparability these characteristics are valid for refurbishment. Nevertheless, features such as the long turn-round time, the number of participants, the complexity and the uncertainty, distinguish housing refurbishment from most services. There is strong empirical support for the claim that customer satisfaction increases customer loyalty and gives the service producer a positive reputation, ultimately increasing profitability. It is concluded that this insight can be interpreted operationally for housing refurbishment projects, bearing in mind that the tenant or the owner of a cooperative flat is the customer's customer.
Miniaturisation and electronic tuning techniques for microstrip spurline filters

A new technique for the miniaturisation and electronic tuning of microstrip spurline filters is presented. The technique is based on connecting a reactive component across the end of the coupling gap of the spurline. The circuit is analysed by using a general coupled-line model, leading to the conclusion that, if a capacitance is used, the filter can be miniaturised or electronically tuned. The analysis leads to a set of simple design equations for these applications and a range of simulations are used to investigate the technique further. The validity of the techniques is demonstrated with three different practical circuits. For a miniaturised spurline filter operating at 1.8 GHz, 50% length reduction is achieved. Two varactor-tuned designs are described: a single-section and a cascaded spurline filter. The single-section spurline can be tuned across almost one octave bandwidth, from 580 MHz to 1.06 GHz whereas the cascaded design achieves tuning range of 320 -723 MHz.
Reflexivity over caste and gender: disrupting researcher’s bias beliefs and habitus

Abstract Reflexivity is not a new concept; however, the researcher’s reflexivity on caste and gender preconception in the South Asian context is an understudied area in qualitative studies. We know less about how a researcher’s prejudice can unconsciously exclude Dalits and females from their research. In this critical autoethnographic study, I extend the concept of reflexivity by illustrating first awareness of the subtle nuances of my own prejudiced disposition and belief against Dalit and female participants, and second how preconceptions can be disrupted by the researcher being conscious of everyday actions in the research field, and questioning moments of awkwardness or difficulties in and out of the field.