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The purpose of this paper is to analyze the effects of white noise perturbations of the input voltage on the band pass filter response, both on pass band and reject band.

By adding white noise term in the input voltage of the filter circuit, the deterministic ordinary differential equation (ODE) is replaced by a stochastic differential equation (SDE). With the application of Ito lemma, the analytical solution of SDE has been obtained. Furthermore, based on the Euler–Maruyama approximation, the numerical simulation for SDE has been done.

Numerical examples are performed using MATLAB programming to show the efficiency and accuracy of the present work.

All previous noise analyses of filter circuits were done using ODEs or component noise formulas in the electrical domain. The stochastic perspective for these circuits is adopted for the first time in this paper.

Structural stress and strain in the key components of aircraft structure is important for structural health monitoring and strength assessment. However, the measure of dynamic strain is often difficult to implement because of the complex test equipment and inconvenient measure points, especially in flight test. This study aims to propose an algorithm of dynamic strain estimation using the acceleration response in time domain to simplify the measure of dynamic strain.

The relationship between the strain and acceleration response is established through the sinusoidal response or modal analysis, which is insensitive to the excitation position and form. A band-pass filter is used to obtain the modal acceleration response, and a filter frequency band selection method is proposed. Then, the dynamic strain at the concerned points can be estimated based on the modal superposition principle.

Simulation and experiment are implemented to validate the applicability and effectiveness of the strain estimation method. The estimated strain results agree well with numerical simulation as well as the experimental results. The simplicity and accuracy of the strain estimation method show practicability for dynamic strength and fatigue analysis in engineering applications.

An algorithm of dynamic strain estimation using the acceleration response in time domain is developed. A band-pass filter is used to obtain the modal acceleration response, and a filter frequency band selection method is proposed. The dynamic strain at the concerned points can be estimated based on the modal superposition principle.

This paper reports the behaviour of a parallel coupled band pass microstrip filter due to an Al₂O₃ thin film‐thick film overlay and the effect of the moisture ambient on the properties of the overlaid microstrip filter. The thickness of the initial thin‐film overlay affects the behaviour of the filter after thick‐film overlay. Moisture has the effect of lowering the transmittance drastically and shifting the pass band to the lower frequency end. The filter loses its band pass characteristics after a few moisture‐heat cycles, indicating irreversible change taking place in the overlay material. It is felt that the ageing aspects of the overlay material should be taken into account when using dielectric overlays for circuit protection and cross‐over insulation purposes.

The purpose of this paper is to introduce modified in–phase and quadrature components (I–Q) demodulator based on low temperature co-fired ceramics (LTCC) dielectric substrate GreenTape 951PX for M-Sequence ultra-wide band (UWB) sensor system.

Microstrip low pass (LP) and band pass (BP) filters for UWB sensor systems with required properties (for both filters, minimum attenuation is −40dB in stopband, bandwidth of pass band is 6 to 8.5 GHz for BP filter and cutoff frequency is 2.5 GHz for LP filter) were designed, simulated, fabricated and measured using dielectric substrates Du Pont GreenTape 951 PX. The developed microstrip filters were integrated with all parts of I–Q demodulator on one multilayer structure based on LTCC substrate Du Pont GreenTape 951 PX.

Both type of microstrip filters integrated in the I– Q demodulator achieved better transmission characteristics in comparison with commercial available filters. It was shown that LTCC technology based on GreenTape 951PX proves good stability in gigahertz frequency and suitability for fabrication of I–Q demodulator with a multilayer approach.

The novelty of this work lies in substituting commercially available LP and BP filters used in I– Q demodulator by microstrip LP and BP filters with better performance and furthermore the I– Q demodulator is fabricated based on LTCC instead of previously used PCB.

Aims to present a simple circuit for the realization of electronically tunable ideal grounded inductor, which consists of two current controlled conveyors along with a grounded capacitor. Also its application for realization of multifunctional filter is demonstrated.

Multifunctional filter (low pass, band pass and high pass filters) is designed using proposed grounded inductor realization which provides standard responses without any constrains in terms of matching conditions.

The multifunctional filter designed using the proposed realization has many attractive features such as low component count, high‐Q, low sensitivity performance, independent Q‐tuning of the filter without affecting its pole frequency.

Simulation results show excellent performance with low power consumption of 1.87 mW at ±2.5 supply voltage.

The purpose of this paper is to present the design and manufacture of embedded passive devices in organic substrates.

Low cost and high performance duplexers have been designed for WiMAX front‐end modules with multi‐layered organic substrates. Band‐pass filters (BPFs) and duplexers for the WiMAX FEM have been embedded in organic substrates. In addition, a new organic substrate manufacturing process has been proposed in order to improve the tolerance of embedded passives in organic substrates.

The overall size of FEM, which includes PA and bypass capacitor, is 5.4×4×1.5 mm. BPFs and duplexer show good electrical performances with low insertion loss and high attenuation. The dual‐band FEM with embedded passive components incorporates the duplexers including 2 and 5 GHz BPFs. The dimensions of BPFs and duplexer are 1.65×1.8×0.12 mm, 1.32×1.2×0.12 mm and 2×2×0.6 mm, respectively. The integrated dual‐band BPFs show an insertion loss < 1.8 dB in path band and 22‐40 dB attenuation performance in rejection band. The newly proposed fabrication process improves the tolerance for embedded capacitors in the organic substrate. This new process provides two main advantages. First, the flat coating process is not required. Second, it has a better copper pattern tolerance since the pattern is achieved with the addictive process. The tolerance of capacitances produced by the newly proposed process is compared with one manufactured by the conventional etching process. The newly proposed process provides a better capacitance tolerance.

In future studies, it is suggested that the tolerance study should include other variations such as thickness, alignment and material properties.

The paper's findings can be used for designing and manufacturing embedded passives devices for wireless applications.

This study shows a technology development in the area of embedded passive devices in organic substrates.

This paper aims to assess the feasibility of the proposed Caribbean Monetary Union (CMU) by examining the synchronization of business cycles within CARICOM. According to the literature on optimum currencies, the synchronization of business cycles is a key requirement for the formation of a monetary union.

In order to extract the business cycles we use the Hodrick‐Prescott (HP) filter and the band pass (BP) filter. For the purposes of measuring synchronization two concepts are used: the simple correlation coefficient and the Concordance statistic of Pagan and Harding. First, the feasibility of enlarging the Eastern Caribbean Currency Union is examined and then consideration is given to the formation of a new monetary union with Trinidad and Tobago as the center.

The paper finds the degree of business cycle synchronization to be weak. This casts doubt on the feasibility of the proposed CMU.

This paper has placed emphasis on the synchronization of business cycles. While the synchronization of business cycles is necessary, is not sufficient for a successful monetary union. Other factors such as political cohesion may be just as important.

This paper's main contribution is that it employs a more rigorous framework and a more comprehensive data set than previous studies.

The purpose of this paper is to analyze the mechanism and filter efficacy of accumulation generation operator (AGO)/inverse accumulation generation operator (IAGO) in the frequency domain.

The AGO/IAGO in time domain will be transferred to the frequency domain by the Fourier transform. Based on the consistency of the mathematical expressions of the AGO/IAGO in the gray system and the digital filter in digital signal processing, the equivalent filter model of the AGO/IAGO is established. The unique methods in digital signal processing systems “spectrum analysis” of AGO/IAGO are carried out in the frequency domain.

Through the theoretical study and practical example, benefit of spectrum analysis is explained, and the mechanism and filter efficacy of AGO/IAGO are quantitatively analyzed. The study indicated that the AGO is particularly suitable to act on the system's behavior time series in which the long period parts is the main factor. The acted sequence has good effect of noise immunity.

The AGO/IAGO has a wonderful effect on the processing of some statistical data, e.g. most of the statistical data related to economic growth, crop production, climate and atmospheric changes are mainly affected by long period factors (i.e. low-frequency data), and most of the disturbances are short-period factors (high-frequency data). After processing by the 1-AGO, its high frequency content is suppressed, and its low frequency content is amplified. In terms of information theory, this two-way effect improves the signal-to-noise ratio greatly and reduces the proportion of noise/interference in the new sequence. Based on 1-AGO acting, the information mining and extrapolation prediction will have a good effect.

The authors find that 1-AGO has a wonderful effect on the processing of data sequence. When the 1-AGO acts on a data sequence X, its low-pass filtering effect will benefit the information fluctuations removing and high-frequency noise/interference reduction, so the data shows a clear exponential change trends. However, it is not suitable for excessive use because its equivalent filter has poles at the non-periodic content. But, because of pol effect at zero frequency, the 1-AGO will greatly amplify the low-frequency information parts and suppress the high-frequency parts in the information at the same time.

The purpose of this paper is to review and provide a detailed performance evaluation of a number of texture descriptors that analyse texture at micro‐level such as local binary patterns (LBP) and a number of standard filtering techniques that sample the texture information using either a bank of isotropic filters or Gabor filters.

The experimental tests were conducted on standard databases where the classification results are obtained for single and multiple texture orientations. The authors also analysed the performance of standard filtering texture analysis techniques (such as those based of LM and MR8 filter banks) when applied to the classification of texture images contained in standard Outex and Brodatz databases.

The most important finding resulting from this study is that although the LBP/C and the multi‐channel Gabor filtering techniques approach texture analysis from a different theoretical perspective, in this paper the authors have experimentally demonstrated that they share some common properties in regard to the way they sample the macro and micro properties of the texture.

Texture is a fundamental property of digital images and the development of robust image descriptors plays a crucial role in the process of image segmentation and scene understanding.

This paper contrast, from a practical and theoretical standpoint, the LBP and representative multi‐channel texture analysis approaches and a substantial number of experimental results were provided to evaluate their performance when applied to standard texture databases.

This article aims to examine empirically the relationship between budget periodicity and expenditure volatility in state governments. Using a large panel dataset for fifty states over the years 1960-2012, after controlling for institutional, economic, and political factors, we find general expenditure of biennial states has been significantly less volatile than that of annual states. The finding suggests that a choice between annual and biennial budget period can emerge as a feasible and effective countercyclical strategy to overcome fiscal difficulties in the short run and promote fiscal stability in the long run.