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1 – 10 of over 14000I. Antoniadis and A. Kanarachos
Although the existence of a close relationship between the areas ofdigital signal processing and time integration methodology is known, asystematic application of the concepts and…
Abstract
Although the existence of a close relationship between the areas of digital signal processing and time integration methodology is known, a systematic application of the concepts and methods of the first area to the second is missing. Such an approach is followed in this paper, arising from the fact that any time integration formula can be viewed as a digital filter of the applied excitation force, approximating as close as possible to the behaviour of a ‘prototype analogue filter’, which is in fact the semi discrete equations of motion of the system. This approach provides a universal framework for handling and analysing all various aspects of time integration formulae, such as analysis in the frequency domain, algebraic operations, accuracy and stability, aliasing, spurious oscillations generation, introduction of digital filters within the time integration formula, initial conditions handling and overshooting. Additionally it is shown that digital signal processing methods, such as pre‐ or post‐processing, time delays, etc. can be in certain cases a quite effective complement of the time integration scheme.
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Mehdi Habibi and Ahmad Reza Danesh
The purpose of this study is to propose a pulse width based, in-pixel, arbitrary size kernel convolution processor. When image sensors are used in machine vision tasks, large…
Abstract
Purpose
The purpose of this study is to propose a pulse width based, in-pixel, arbitrary size kernel convolution processor. When image sensors are used in machine vision tasks, large amount of data need to be transferred to the output and fed to a processor. Basic and low-level image processing functions such as kernel convolution is used extensively in the early stages of most machine vision tasks. These low-level functions are usually computationally extensive and if the computation is performed inside every pixel, the burden on the external processor will be greatly reduced.
Design/methodology/approach
In the proposed architecture, digital pulse width processing is used to perform kernel convolution on the image sensor data. With this approach, while the photocurrent fluctuations are expressed with changes in the pulse width of an output signal, the small processor incorporated in each pixel receives the output signal of the corresponding pixel and its neighbors and produces a binary coded output result for that specific pixel. The process is commenced in parallel among all pixels of the image sensor.
Findings
It is shown that using the proposed architecture, not only kernel convolution can be performed in the digital domain inside smart image sensors but also arbitrary kernel coefficients are obtainable simply by adjusting the sampling frequency at different phases of the processing.
Originality/value
Although in-pixel digital kernel convolution has been previously reported however with the presented approach no in-pixel analog to binary coded digital converter is required. Furthermore, arbitrary kernel coefficients and scaling can be deployed in the processing. The given architecture is a suitable choice for smart image sensors which are to be used in high-speed machine vision tasks.
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Changhai Lin, Zhengyu Song, Sifeng Liu, Yingjie Yang and Jeffrey Forrest
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Practical implications
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.
Originality/value
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.
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Ivars Bilinskis and Gerald Cain
Addresses the problem of full digital processing of sensor signals at frequencies in the microwave and radio frequency range. Discusses advantages and drawbacks of the emerging…
Abstract
Addresses the problem of full digital processing of sensor signals at frequencies in the microwave and radio frequency range. Discusses advantages and drawbacks of the emerging digital alias‐free signal processing technology considering it as a new DSP tool prospective for achieving a breakthrough in DSP theory and techniques leading to a stepwise enlarging of the DSP application frequency range.
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Elena Fedorova, Daria Aleshina and Igor Demin
The goal of this work is to evaluate how digital transformation disclosure in corporate news and press releases affects stock prices. We examine American and Chinese companies…
Abstract
Purpose
The goal of this work is to evaluate how digital transformation disclosure in corporate news and press releases affects stock prices. We examine American and Chinese companies from the energy and industry sectors for two periods: pre-COVID-19 and during the COVID-19 pandemic.
Design/methodology/approach
To estimate the effects of disclosure of information related to digital transformation, we applied the bag-of-words (BOW) method. As the benchmark dictionary, we used Kindermann et al. (2021), with the addition of original dictionaries created via Latent Dirichlet allocation (LDA) analysis. We also employed panel regression analysis and random forest.
Findings
For USA energy sector, all aspects of digital transformation were insignificant in pre-COVID-19 period, while sustainability topics became significant during the pandemic. As for the Chinese energy sector, digital strategy implementation was significant in pre-pandemic period, while digital technologies adoption and business model innovation became relevant in COVID-19 period. The results show the greater significance of digital transformation aspects for industrials sectors compared to the energy sector. The result of random forest analysis proves the efficiency of the authors’ dictionary which could be applied in practice. The developed methodology can be considered relevant.
Originality/value
The research contributes to the existing literature in theoretical, empirical and methodological ways. It applies signaling and information asymmetry theories to the financial markets, digital transformation being used as an instrument. The methodological contribution of this article can be described in several ways. Firstly, our data collection process differs from that in previous papers, as the data are gathered “from investor’s point of view”, i.e. we use all public information published by the company. Secondly, in addition to the use of existing dictionaries based on Kindermann et al. (2021), with our own modifications, we apply the original methodology based on LDA analysis. The empirical contribution of this research is the following. Unlike past works, we do not focus on particular technologies (Hong et al., 2023) connected with digital transformation, but try to cover all multi-dimensional aspects of the transformational process and aim to discover the most significant one.
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Ntogas Nikolaos and Ventzas Dimitrios
The purpose of this paper is to introduce an innovative procedure for digital historical documents image binarization based on image pre‐processing and image condition…
Abstract
Purpose
The purpose of this paper is to introduce an innovative procedure for digital historical documents image binarization based on image pre‐processing and image condition classification. The estimated results for each class of images and each method have shown improved image quality for the six categories of document images described by their separate characteristics.
Design/methodology/approach
The applied technique consists of five stages, i.e. text image acquisition, image preparation, denoising, image type classification in six categories according to image condition, image thresholding and final refinement, a very effective approach to binarize document images. The results achieved by the authors' method require minimal pre‐processing steps for best quality of the image and increased text readability. This methodology performs better compared to current state‐of‐the‐art adaptive thresholding techniques.
Findings
An innovative procedure for digital historical documents image binarization based on image pre‐processing, image type classification in categories according to image condition and further enhancement. This methodology is robust and simple, with minimal pre‐processing steps for best quality of the image, increased text readability and it performs better compared to available thresholding techniques.
Research limitations/implications
The technique consists of limited but optimized pre‐processing sequential steps, and attention should be given in document image preparation and denoising, and on image condition classification for thresholding and refinement, since bad results in a single stage corrupt the final document image quality and text readability.
Originality/value
The paper contributes in digital image binarization of text images suggesting a procedure based on image preparation, image type classification and thresholding and image refinement with applicability on Byzantine historical documents.
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Omotayo Farai, Nicole Metje, Carl Anthony, Ali Sadeghioon and David Chapman
Wireless sensor networks (WSN), as a solution for buried water pipe monitoring, face a new set of challenges compared to traditional application for above-ground infrastructure…
Abstract
Purpose
Wireless sensor networks (WSN), as a solution for buried water pipe monitoring, face a new set of challenges compared to traditional application for above-ground infrastructure monitoring. One of the main challenges for underground WSN deployment is the limited range (less than 3 m) at which reliable wireless underground communication can be achieved using radio signal propagation through the soil. To overcome this challenge, the purpose of this paper is to investigate a new approach for wireless underground communication using acoustic signal propagation along a buried water pipe.
Design/methodology/approach
An acoustic communication system was developed based on the requirements of low cost (tens of pounds at most), low power supply capacity (in the order of 1 W-h) and miniature (centimetre scale) size for a wireless communication node. The developed system was further tested along a buried steel pipe in poorly graded SAND and a buried medium density polyethylene (MDPE) pipe in well graded SAND.
Findings
With predicted acoustic attenuation of 1.3 dB/m and 2.1 dB/m along the buried steel and MDPE pipes, respectively, reliable acoustic communication is possible up to 17 m for the buried steel pipe and 11 m for the buried MDPE pipe.
Research limitations/implications
Although an important first step, more research is needed to validate the acoustic communication system along a wider water distribution pipe network.
Originality/value
This paper shows the possibility of achieving reliable wireless underground communication along a buried water pipe (especially non-metallic material ones) using low-frequency acoustic propagation along the pipe wall.
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Qiang Lu, Yihang Zhou, Zhenzeng Luan and Hua Song
This study empirically investigates how ambidextrous innovations and their balancing affect the supply chain financing performance (SCFP) of small and medium-sized enterprises…
Abstract
Purpose
This study empirically investigates how ambidextrous innovations and their balancing affect the supply chain financing performance (SCFP) of small and medium-sized enterprises (SMEs), based on signaling theory. Moreover, this study explores the moderating effect of the breadth and depth of digital technology deployment on the relationship between ambidextrous innovations and the SCFP of SMEs.
Design/methodology/approach
A mixed-methods design is used, including a qualitative study and a quantitative study. Qualitative data have been collected from six multi-cases in different industries. Questionnaire data have been collected from 259 SMEs in China, and a multiple regression model is used to verify the research hypotheses.
Findings
The findings indicate that, in supply chain financing, both exploitative innovation and exploratory innovation are helpful in improving the SCFP of SMEs. For resource-constrained SMEs, a relative balance between exploitative innovation and exploratory innovation can help improve SCFP. The breadth of digital technology deployment can strengthen the relationship between exploitative innovation and SCFP, while the depth of digital technology deployment can weaken the relationship between exploratory innovation and SCFP. In addition, increasing the depth of digital technology deployment strengthens the positive correlation between the relative balance of ambidextrous innovations and SCFP.
Practical implications
To effectively obtain supply chain financing, SMEs can either concentrate their limited resources on a single type of innovation or use relative balance strategies to simultaneously pursue two innovations. In addition, in the process of obtaining supply chain financing by ambidextrous innovations, SMEs should appropriately deploy digital technologies.
Originality/value
This study first deconstructs the impact mechanism of ambidextrous innovation capabilities on SCFP based on signaling theory, and then discusses the balancing effect of ambidextrous innovations on SCFP in the cases of resource-constrained SMEs. This study also goes further and finds the negative moderating effect of digital technology deployment in the process of supply chain financing.
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An introduction to disc‐based audio‐video technologies
Abstract
Purpose
An introduction to disc‐based audio‐video technologies
Design/methodology/approach
Description of the basic disc‐based audio‐video technologies.
Findings
Provides the baseline for types of disc‐based audio‐video technology such as holographic video disc (HVD), BluRay, HD DVD, DVD‐Audio and others.
Originality/value
This paper is useful for information management professionals who seek greater understanding of the basics disc storage medium.
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Jivan Shrikrishna Parab, Rupesh Sadanand Paliekar Porob, Kottanal Roy Francis Joseph, Kunal Vishwanath Naik, Rajanish K. Kamat and Gourish M. Naik
Aims to design a heterogeneous embedded system with CPLD and microcontroller as co‐processors sharing a memory module.
Abstract
Purpose
Aims to design a heterogeneous embedded system with CPLD and microcontroller as co‐processors sharing a memory module.
Design/methodology/approach
The system receives external analog input signal, which is applied to the PIC 16F73 microcontroller. Upon converting the data in to digital format using the on‐chip ADC, the PIC stores the digitized version in the SRAM (HCM 6264) chip. SRAM HCM 6264 has been used as a shared memory model, of which both the PIC and CPLD can access all the locations. Once the PIC passes controls to the CPLD, the further processing is carried out by the CPLD without any intervention of the PIC. This is a true example of co‐processing of the architecturally diversified computing modules from completely different vendors with totally different programming suits.
Findings
The board has been tested with IC temperature sensors and also found to be useful for sensor array applications involving three types of processing viz. analog (through instrumentation amplifier), real‐time digital (through microcontroller) and customized reconfigurable digital (with the CPLD).
Practical implications
The system has several potential applications in avionics, military and robotic embedded systems, which have inherent real‐time constraints that need to be supported by the underlying hardware and driver programs.
Originality/value
Discusses the rare and unique combination of diversified processing core to build an embedded system.
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