Miracle-dz/UniFAR-FTUs huggingface dataset:
TEC retrieval from spaceborne SAR data and its applications

It is well known that the spaceborne synthetic aperture radar (SAR) at VHF‐UHF band can be seriously affected by the ionosphere. Thus, the geophysical information of the ionosphere will be embedded in the low‐frequency SAR echoes after they transverse the ionosphere. Correspondingly, the total electron content (TEC), a typical ionospheric information parameter, can be retrieved from the spaceborne SAR data. However, the existing dual‐band techniques for TEC retrieval usually do not include consideration of multiple scattering effects caused by turbulent ionosphere, which plays an important role in the total path delay of signal under the strong fluctuation regimes. The result of TEC retrieval is therefore inaccurate and not applicable. Aiming at this issue, first, this paper analyzes the effects of regular background and the irregularity of electron density on SAR at L‐band, and the theoretical formulation is given. Then, a triband path delay technique of TEC retrieval based on the SAR data is proposed. By using three path delays corresponding to three specific frequencies within the signal bandwidth, this technique can remove the errors of multiple scattering due to the irregularity, and a high accuracy resolution of TEC value therefore can be obtained. Meanwhile, the sensitivity of this technique is analyzed. Finally, compared with traditional dual‐band technique, the numerical simulations show that the correction of SAR imaging based on triband technique is improved significantly. In addition, the resolution of reconstruction imaging using computerized ionospheric tomography performs significantly better based on the triband technique.
Resource-Constrained Embedded Control and Computing Systems

This thesis deals with methods for handling resource constraints in embedded control systems and real-time computing systems. By dynamic feedback-based resource scheduling it is possible to achieve adaptability andincreased performance for these systems. A feedback scheduling strategy is presented, which uses feedback from plant states to distribute computing resources optimally among a set of controller tasks. Linear-quadratic controllers are analyzed, and expressions relating the expected cost to the sampling period and the plant state are derived and used for on-line sample-rate adjustments. A flexible implementation of model predictive control (MPC) tasks is described. A termination criterion is derived that, unlike traditional MPC, takes the effects of computational delay into account in the optimization. A scheduling scheme is also described, where the MPC cost functions being minimized are used as dynamic task priorities for a set of MPC tasks. A method for optimizing the use of computational resources in a multi-camera-based positioning system is studied. The covariance of the estimation error is minimized, while meeting computation time constraints. A novel predictor for delay control in server systems is introduced. The predictor uses instantaneous measurements of queue length and arrival times and is continuously updated as new requests arrive according to a receding horizon principle. The predictor is evaluated in simulation and by experiments on an Apache web server. The MATLAB/Simulink-based simulator TrueTime is presented. TrueTime is a codesign tool that facilitates simulation of distributed real-time control systems. TrueTime also supports simulation of wireless communication and resource constraints associated with wireless sensor/actuator networks.
Time-frequency peak filtering applied to FSK signals

This paper considers the problem of non-coherent detection of M-ary frequency-shift-keyed signals embedded in white Gaussian noise. The time-frequency peak filter (TFPF) is suggested as a technique to improve the signal-to-noise ratio of these signals before detection. First the method of TFPF is briefly reviewed and it is shown that TFPF is in general biased when the peak of the Wigner-Ville distribution (WVD) is used to estimate the signal instantaneous frequency. Then criteria are given for determining the reduced bias pseudo WVD window length which allows for practical implementation. Finally we demonstrate using simulations, the effectiveness of TFPF for improving non-coherent detection of MFSK signals. <<ETX>>
A new single-ended artificial neural network-based protection scheme for shunt faults in six-phase transmission line

Summary In this paper, modular concept of artificial neural network (ANN)-based technique is introduced to identify and locate all type of shunt faults (120) in a six-phase transmission line. The proposed algorithm is composed of two stages. In the first stage, ANN-based algorithm has been developed to detect and classify all possible types of shunt faults within one cycle time. Then, the second stage dispenses the location of shunt faults. Total 11 numbers of modular ANNs have been developed in both the stages which are based on the fundamental components of voltage and current signals at the sending end of transmission line only. For validation of the proposed scheme, simulation studies have been carried out on a six-phase transmission system. The test results of ANN-based fault detector/classifier and locator indicate that the proposed algorithm correctly detects/classifies and locates the shunt faults. The results demonstrate high speed, reliability and suitability of the proposed technique and its adaptability to changing system conditions viz. fault type, fault inception angle, fault location, high fault resistance, short circuit capacity of source and its X/R ratio. Even the cases of slight variations in system frequency, generated voltage and initial power flow angle are also taken into account. Copyright © 2014 John Wiley & Sons, Ltd.
Passive eddy-current damping as a means of vibration control in cryogenic turbomachinery

Lateral shaft vibrations produced by a rotating unbalance weight were damped by means of eddy currents generated in copper conductors that were precessing cyclicly in the gap formed by the pole faces of C-shaped, permanent magnets. The damper assembly, which was located at the lower bearing support of a vertically oriented rotor was completely immersed in liquid nitrogen during the test run. The test rotor was operated over a speed range from 800 to 10,000 rpm. Three magnet/conductor designs were evaluated. Experimental damping coefficients varied from 180 to 530 N sec/m. Reasonable agreement was noted for theoretical values of damping for these same assemblies. Values of damping coefficients varied from 150 to 780 N sec/m. The results demonstrate that passive eddy-current damping is a viable candidate for vibration control in cryogenic turbomachinery.
A review of vocabulary learning applications: From the aspects of cognitive approaches, multimedia input, learning materials, and game elements

In recent years, mobile applications (apps) have been increasingly used and investigated as a vocabulary learning approach. Despite the extensive use of commercial English as a Foreign Language (EFL) vocabulary learning apps in China, there is a lack of a review of these apps for a systematic understanding of the components and usefulness of app-assisted vocabulary learning. To fill this knowledge gap, this study presents a systematic review of 15 EFL vocabulary learning apps that were most downloaded in China, focusing on how these apps help students develop word knowledge. The results of this study showed that most apps enabled students to access word knowledge through translating words into their native language. Notably, word knowledge was usually presented through text-plus-image and text-plus-image-plus-audio. Most of these mobile apps provided sentence examples as vocabulary learning materials. Many of these apps were integrated with game elements, especially in interactivity or feedback systems and reward systems. Based on the review results, we have provided three recommendations to vocabulary learning app developers concerning the use of video for the input of word knowledge, the efficiency of vocabulary learning, and the integration of more game elements.
THE LATERAL DYNAMICS OF MOTORCYCLES AND BICYCLES

SUMMARY The paper is a review of the state of knowledge and understanding of the steering behaviour of single-track vehicles, with the main accent on vehicle design, and vehicle design analysis and behaviour prediction. The body of the paper consists of a chronological account of the steps which have been taken in establishing the current position. Scientific study of the motions of two-wheelers has been in progress for more than 100 years, but progress was slow and many conflicting conclusions were drawn until increasing understanding of tyre mechanics, systematic application of the laws of motion for systems of rigid bodies, digital computation and modern numerical methods, and improved mobile measurement, recording, and data processing capabilities allowed the pace to accelerate. The current position, which is that a good understanding of the relationship between design and performance has been achieved, but that by no means have all the problems of significance been solved, is described at the end of .
Identification in closed‐loop operation of models for collective pitch robust controller design

To achieve load reduction and power optimization, wind turbine controllers design requires the availability of reliable control-oriented linear models. These are needed for model-based controller design. Model identification of wind turbine while operating in closed loop is an appropriate solution that has recently shown its capabilities when linear time-invariant controllers and complicated control structures are present. However, the collective pitch control loop, one of the most important wind turbine loops, uses non-linear controllers. Typically, this non-linear controller is a combination of a linear controller and a gain scheduling. This paper presents a new algorithm for identification in closed-loop operation that allows the use of this kind of non-linear controllers. The algorithm is applied for identification the collective pitch demand to generator speed of a wind turbine at various operating points. The obtained models are presented and discussed from a control point of view. The validity of these models is illustrated by their use for the design of a linear fix robust controller. The performance based on simulation data of this linear controller is similar to that obtained with simulations based on a linear controller with gain scheduling, but its design and implementation is much simpler. Copyright © 2012 John Wiley & Sons, Ltd.
Undertaking HRD research in higher education: A longitudinal approach to evaluating undergraduate “enterprise education” modules

Purpose – Educational programmes that are concerned with the learning and teaching of enterprise education, such as enterprise focused degrees and/or modules, could be argued to be of particular interest to human resource development (HRD) research since they commonly have an overt focus on influencing and shaping the career choices of students. Furthermore, the perceptions of students about their own career choices are also of immense value, especially in a period of economic downturn and financial uncertainty. The main aim of this paper is to report problems encountered by the authors when attempting to evaluate the impact of enterprise modules in higher education, in the context of HRD research. The paper also aims to discuss the evaluation of learning by students studying enterprise modules.Design/methodology/approach – The research strategy for this project consisted of a longitudinal approach, initially over the course of three years using a pre‐designed research instrument (known as the EHGI questi.
Frequency allocations and regulations in the 50-to-70-GHz band

Industry Canada, a Ministry of the Canadian federal government, is planning to implement policies for the use of the 50-70-GHz band. In aid of establishing regulations for Canada, a review of the allocations and rules of other countries has been conducted. The results of this review are being evaluated by the Radio Advisory Board of Canada (RABC), which will make policy recommendations to Industry Canada. A summary of the terrestrial (fixed and mobile) allocations and regulations of the US, Europe, UK, Australia, and Japan for the 50-70-GHz band is presented herein.
Fire Modeling Using CFD - An introduction for Fire Safety Engineers

Fundamental laws of nature used in field modelling using Computational Fluid Dynamics are discussed and explained. Extensions and models used to complement these basic laws of physics in fire specific scenarios are also discussed. The field model SOFIE, Simulation Of Fires In Enclosures, has been used and predictions of gas-temperature, gas-velocity and presence of combustion gases are compared to experimental results from three different experimental series.
Penerapan Algoritma Squeezer Untuk Memberikan Rekomendasi Pilihan Lagu Berdasarkan Daftar Lagu Yang Dimainkan Pada Pemutar Mp3 Android

Pada tulisan ini dibuat sebuah aplikasi pemutar mp3 pada perangkat Android dan juga layanan web yang terintegrasi menjadi sebuah sistem yang dapat memberikan rekomendasi lagu kepada penggunanya. Rekomendasi yang diberikan akan didasarkan pada riwayat lagu yang sering didengarkan oleh pengguna. Untuk menghasilkan rekomendasi digunakan algoritma Squeezer. Algoritma Squeezer membantu dalam mengelompokkan riwayat lagu pengguna dan memberikan rekomendasi lagu baru yang mirip dengan kelompok riwayat lagu yang paling besar. Berdasarkan hasil pengujian yang dilakukan tingkat akurasi rekomendasi yang diberikan mencapai 80% serta mendapat respon yang baik dari pengguna.
A participatory action research study of knowledge management implementation in a large European telecommunication company in their UK office

Knowledge management is being highlighted as a major source of sustained competitive advantage for contemporary organisations. Deploying knowledge management programs presents many challenges and this is evident by the high failure rate of initiatives. Conventional research techniques have failed to develop a rich understanding of the major implementation barriers and have therefore provided minimal assistance to practicing managers. This paper discusses the importance of knowledge to customer support organisations in the telecommunications sector and how one European support organisation approached the deployment of knowledge-centric support in their UK office. The deployment approach incorporates a participatory action research framework that facilitates research and project delivery and ensures practising managers have learning outcomes that can be applied in their organisations.
Small-scale water reuse for urban agriculture in Namibia: Modeling water flows and productivity

Treating and reusing municipal wastewater for urban agriculture raises water productivity. This paper developed a methodology to quantify water flows and productivity of a proposed infrastructure including water supply, sanitation, wastewater treatment and water reuse for agriculture. The methodology consists in calculating the pathogen reduction achieved with wastewater treatment, designing a crop scheme for the irrigation with treated water, modeling irrigation requirements and quantifying water flows with mathematical material flow analysis. This methodology was applied for the current state and with the planned facility in semi-arid Namibia. This infrastructure has the potential to raise water productivity by +10% as household water use increases with improved sanitation. Compared to not reusing the water for agriculture, water productivity can be raised by +39%. This methodology allowed the consideration of the impact of facility user behavior on water flows and found that water productivity increases less than computed with a fixed wastewater inflow.
On-wafer calibration techniques for giga-hertz CMOS measurements

This paper presents five different methods for performing on-wafer calibration of RF CMOS measurements. All methods are compatible with standard CMOS technology. A comparison of method performance up to 12 GHz is made with measurements on RF CMOS devices. The results verify that substrate and metallization losses must be considered to obtain high accuracy. Fixture design issues are discussed and a method for mitigating overestimation of DUT performance is suggested.
Aplikasi Peramalan Kurs Valuta Asing Rupiah per Dollar Amerika Serikat dengan Menggunakan Metode Box-Jenkins (ARIMA)

ABSTRACT For a multinational company foreign exchange is one of key variable in their day to day activity. The ability in managing their forex portfolio could help them to achieve a good performance. This research was applying The Box – Jenkins Method in order to forecast USD to IDR fluctuation. Using this method we find that it is suitable to apply this method for forecasting USD vis a vis IDR fluctuation. We find the USD-IDR fluctuation statistically significant following an ARMA (2,1) process but for forecasting purposes it is better to use ARMA (4,1) process since this process have better explanatory power. We recommend using higher data frequency such as daily or weekly data for a better forecasting result and for the applicability of this model to the real world. Kata Kunci: Kurs, nilai tukar, ARIMA Model, Time Series Forecasting
Electron Wave Packet Dynamics on the Attosecond Time Scale

One objective of attosecond science is to study electron dynamics in atoms and molecular systems on their natural time scale. This can be done using attosecond light pulses. Attosecond pulses are produced in a process called high-order harmonic generation, in which a short, intense laser pulse interacts with atoms or molecules in a highly nonlinear process, leading to the generation of high-order frequencies of the fundamental laser with a large spectral bandwidth, supporting pulses with attosecond duration. In some condition the harmonics are locked in phase leading to a train of attosecond pulses or, in some cases, to a single attosecond pulse. This thesis presents experiments based on interferometry to study electron dynamics using attosecond pulses. The first part describes a series of experiments, in which the dynamics of electrons was studied after photoionization with an attosecond pulse train. The time resolution in these experiments was achieved by measuring the accumulated phase of the free electron wave packet after photoemission using an interferometric technique. The phase carries temporal information about the ionization process, from which the delay in photoemission can be determined with a much better time resolution than that given by the temporal structure of the pulse train. The same technique was applied to investigate the phase behavior of resonant two-photon ionization in helium atoms. The second part describes the application of an interferometric pump-probe technique to characterize bound electron wave packets. Single attosecond pulses are used to excite a broad electron wave packet containing bound and continuum states. The bound part of the wave packet is further ionized by an infrared laser with a variable delay. Analysis of the resulting interferogram allows for full reconstruction of the bound wave packet, since both the amplitude and the phase of all ingoing states in the wave packet are encoded in the interference pattern.
Www.regulation: the why, what and whither of communications regulation

Regulation is as controversial today as ever before. Some call for a 'lighter touch' while others demand stronger intervention to create 'Broadband Britain'. The author describes what regulators do and why, Oftel's accountability, the role of the engineer within Oftel and the forthcoming changes that will create OFCOM, the Office for Communications, from five existing communications regulators.
A technique of electromagnetic interference measurements with high-impedance electric and low-impedance magnetic fields inside a TEM cell

Transverse electromagnetic (TEM) cells are usually used to perform electromagnetic interference (EMI) measurements of equipment inside the cell in a plane wave-field environment. A newly developed technique of generating predominantly high-impedance electric or low-impedance magnetic fields inside a TEM cell for EMI measurements of relatively small printed circuit boards (PCBs), electronic devices, etc., is described. The technique simulates environments similar to the near-field EMI environment for intrasystem EMI/EMC (electromagnetic compatibility) studies. Variations of electric and magnetic fields, as well as impedances along the length of the cell, are given. The results indicate that a test region of reasonable size exists in the cell over which the field amplitudes are uniform within +or-1 dB. <<ETX>>
Survey of Tea (Camellia Sinensis L.) Insect Pests in Southwest Ethiopia

Tea is a perennial crop, grown as a monoculture and one of the most popular beverages. The objectives of the study were to collect, identify and prioritize major insect pest species that constrain tea production in the Southwest. Wushwush, Gumaro, and East Africa and their surrounding tea out grower’s farms were considered in the survey and assessed from 77 tea farms. Different insect pests were observed feeding various plant parts of tea in field. Among them, tea aphid and termite were considered as major pests. The percent of farm infestation of aphids was 85% at East Africa, 40% at Gumaro, 50% at Jimma research center. Most of the minor insect pests of tea were recorded from various farms. There was highly significant (p<0.001) variation in access to crop protection training among farmers and only 31.2 % of them took training. Generally, there were variations of species and infestation of insect pests’between and within tea plantations. Although most of the insects recorded during the study period have been considered as minor, it is not unlikely that any one of the minor pests may attain the status of major pests depending upon the environmental conditions. Therefore, the present findings calls regular monitoring of tea gardens in different ecological range and it could also provide good knowledge of all prevailing pest problems.
AlN-based lossy ceramics for high power applications

This paper presents materials properties and RF cold test results obtained for several types of Ceradyne aluminum nitride (AIN) based electromagnetically lossy dielectrics. These materials have been recently developed as an alternative to beryllia (BeO) based materials. Historically, BeO-SiC composites have been the material of choice for high average power microwave/millimeter-wave applications because of their relatively high thermal conductivity (130 W/m-K). However, growing concerns over beryllium-related health/environmental issues, a shrinking supply base, and the limited number of machining/grinding facilities capable of handling beryllium-based materials have prompted the development of more environmentally-friendly alternatives.