Search results

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.

Microstructure noise contaminates high-frequency estimates of asset price volatility. Recent work has determined a preferred sampling frequency under the assumption that the properties of noise are constant. Given the sampling frequency, the high-frequency observations are given equal weight. While convenient, constant weights are not necessarily efficient. We use the Kalman filter to derive more efficient weights, for any given sampling frequency. We demonstrate the efficacy of the procedure through an extensive simulation exercise, showing that our filter compares favorably to more traditional methods.

The purpose of this chapter is to present a model (Beginning, Acting, Telling (BAT) model) developed for the elementary-school classroom that integrates features identified by research into information-seeking behavior and information literacy.

The chapter provides an overview of research in the areas of information-seeking behavior and information literacy and models in which they have intersected (namely, the Information Search Process (ISP) model) to provide a theoretical framework in which to situate the BAT model. Examples from previous empirical studies conducted by the author that informed the model are provided.

A preliminary iteration of the BAT model has successfully been piloted in two third-grade classrooms in Buffalo, New York. Plans are underway to introduce the model to a wider audience.

The BAT model with its use of image and mnemonic cues can be used to teach the research process to students, beginning in the earliest grades of elementary school.

This chapter is the first time the final iteration of the BAT model has been presented. It is the first model integrating features inherent in information-seeking behavior and information literacy that also makes use of imagery and mnemonic.

The information which has hitherto appeared in the daily press as to the evidence laid before the Departmental Committee which is inquiring into the use of preservatives and colouring matters can hardly have afforded pleasant reading to the apologists for the drugging of foods. It is plainly the intention of the Committee to make a thorough investigation of the whole subject, and the main conclusions which, in the result, must bo forced upon unbiassed persons by an investigation of this character will be tolerably obvious to those who have given serious attention to the subject. At a later stage of the inquiry we shall publish a full account of the evidence submitted and of the Committee's proceedings. At present we may observe that the facts which have been brought forward fully confirm the statements made from time to time upon these matters in the BRITISH FOOD JOURNAL, and amply justify the attitude which we have adopted on the whole question. Representatives of various trade interests have given evidence which has served to show the extent to which the practices now being inquired into are followed. Strong medical evidence, as to the dangers which must attach to the promiscuous and unacknowledged drugging of the public by more or less ignorant persons, has been given; and some medical evidence of that apologetic order to which the public have of late become accustomed, and which we, at any rate, regard as particularly feeble, has also been put forward. Much more will no doubt be said, but those who have borne the heat and burden of the day in forcing these matters upon the attention of the Legislature and of the public can view with satisfaction the result already attained. Full and free investigation must produce its educational effect ; and whatever legal machinery may be devised to put some kind of check upon these most dangerous forms of adulteration, the demand of the public will be for undrugged food, and for a guarantee of sufficient authority to ensure that the demand is met.

The purpose of this paper is to determine which criteria should be taken into account while choosing face masks for pandemic times and to what extent their effects are.

Nine face mask alternatives were evaluated based on the assessments of their performance with respect to twelve attributes. Seven experts were asked to evaluate the mask alternatives and the influences among attributes. In gathering expert judgments, spherical fuzzy number-based linguistic terms were utilized in the study to provide a more comprehensive representation domain to them.

According to the results, the most important attributes are found as material type, cost and bacteria–virus protection level. The best face mask is N95, which is followed by respirators and surgical masks.

The implication of the research is to evaluate face masks in terms of criteria such as physical, performance, protection and cost to decide on what basis they were selected as a personal protective equipment (PPE) based on expert assessments. This is useful in selection of the right face mask with optimum performance and provides guidance to the general public and profession specific groups for this purpose. The face mask companies might be also benefitted from the implications of the present study in their design and research and development (R&D) operations.

The preference ranking of the face mask alternatives has not been studied in detail yet in the literature. Focusing on this issue, the present study provides a comprehensive assessment of the selection criteria of face masks in the pandemic era.

This paper seeks to understand how users determine credibility in the internet environment from a conceptual level and the implications of these new methods of credibility determination on internet tools (primarily software) and services.

The author first examines the underlying reasons for increased dependence on the internet for information, using electronic commerce as a starting point. The central concept of “information self‐sufficiency” is introduced and then examined through the lens of the internet and conversation theory.

The author finds that users are shifting from more traditional “authority” methods of credibility determination, where users cede determinations to trusted third parties, to a “reliability” approach where users seek commonalities and coherence among multiple information sources. This has led to an increased pressure for participation and openness at all levels of the internet.

Studies on users and credibility must better account for often invisible technical factors.

Libraries must take into account a greater need for participation and technical fluency when dealing with patrons, particularly in information literacy programs and instruction.

This paper presents a large‐scale conceptual approach to credibility on the internet. It seeks to inform current approaches to the subject nested in communications and instruction with the unique technical environment of the internet.

This study aims to describe the preparation of antimicrobial material usable in 3D printing of medical devices. Despite the wealth of technological progress at the time of the crisis caused by SARS-CoV-2 virus: Virus that causes current Pandemic situation (COVID-19), the global population had long been exposed beforehand to an acute absence of essential medical devices. As a response, a new type of composite materials intended for rapid prototyping, based on layered silicate saponite (Sap), antimicrobial dye phloxine B (PhB) and thermoplastics, has been recently developed.

Sap was modified with a cationic surfactant and subsequently functionalized with PhB. The hybrid material in powder form was then grounded with polyethylene terephthalate-glycol (PETG) or polylactic acid (PLA) in a precisely defined weight ratio and extruded into printing filaments. The stability and level of cytotoxicity of these materials in various physiological environments simulating the human body have been studied. The applicability of these materials in bacteria and a yeast-infected environment was evaluated.

Ideal content of the hybrid material, with respect to thermoplastic, was 15 weight %. Optimal printing temperature and speed, with respect to maintaining antimicrobial activity of the prepared materials, were T = 215°C at 50 mm/s for PETG/SapPhB and T = 230°C at 40 mm/s for PLA/SapPhB. 3 D-printed air filters made of these materials could keep inner air flow at 63.5% and 76.8% of the original value for the PLA/SapPhB and PETG/SapPhB, respectively, whereas the same components made without PhB had a 100% reduction of airflow.

The designed materials can be used for rapid prototyping of medical devices.

The new materials have been immediately used in the construction of an emergency lung ventilator, Q-vent, which has been used in different countries during the COVID-19 crisis.

The purpose of this paper is to explore how education for sustainable development (ESD) was measured in the taught curriculum at the University of Bristol (UoB), providing comparison to other methods of measurement and how measurements were used to engage academics in considering the visibility of the penetration of sustainable development into their teaching.

The process of designing a quantitative and comparative method of reviewing ESD utilising a reflective process at the UoB is considered, which can be applied by other institutions. The UoB decided on an in-house method of assessment using the Unit and Programme Catalogue, a list of all taught units. Initially this revealed that some information relating to ESD was not clearly articulated. A school ESD review refined the data along with the release of key information set data, a nationally published data set which identifies mandatory, typical and optional diets taken by students on programmes.

Text-based methods of assessing ESD penetration into programmes of study have limited use as direct measures of sustainability visibility in programmes, but can be improved by using interpretative methodologies. The combination of quantitative and qualitative methodologies can produce data, which is a useful catalyst for academic reflection. Most importantly, it provides a tool for engagement while also enabling the targeting of resources and support. The UoB has avoided the pitfalls of manipulatable text count methods, and shown that comparative methods can be combined effectively with real engagement with academics and students for a measurement method that showcases good practice.

Increasingly, universities and the higher education sector more widely are looking to embed ESD. To assess progress, systems of measurement and monitoring are required. This case study shares a replicable methodology combining quantitative and qualitative methods developed at the UoB which has been used by academics as a reflective tool to change their practice.

Nature and occurrence of food-borne pathogens in raw and processed food products evolved greatly in the past few years due to new modes of transmission and resistance build-up against sundry micro-/macro-environmental conditions. Assurance of food health and safety thus gained immense importance, for which bio-sensing technology proved very promising in the detection and quantification of food-borne pathogens. Considering the importance, different studies have been performed, and different biosensors have been developed. This study aims to summarize the different biosensors used for the deduction of food-borne pathogens.

The present review highlights different biosensors developed apropos to food matrices, factors governing their selection, their potential and applicability. The paper discusses some related key challenges and constraints and also focuses on the needs and future research prospects in this field.

The shift in consumers’ and industries’ perceptions directed the further approach to achieve portable, user and environmental friendly biosensing techniques. Despite of these developments, it was still observed that the comparison among the different biosensors and their categories proved tedious on a single platform; since the food matrices tested, pathogen detected or diagnosed, time of detection, etc., varied greatly and very few products have been commercially launched. Conclusively, a challenge lies in front of food scientists and researchers to maintain pace and develop techniques for efficiently catering to the needs of the food industry.

Biosensors deduction limit varied with the food matrix, type of organism, material of biosensors’ surface, etc. The food matrix itself consists of complex substances, and various types of food are available in nature. Considering the diversity of food there is a need to develop a universal biosensor that can be used for all the food matrices for a pathogen. Further research is needed to develop a pathogen-specific biosensor that can be used for all the food products that may have accuracy to eliminate the traditional method of deduction.

The present paper summarized and categorized the different types of biosensors developed for food-borne pathogens.

The purpose of this paper is to analyze the spectral characteristics of moving average operator and to propose a novel time-frequency hybrid sequence operator.

Firstly, the complex data is converted into frequency domain data by Fourier transform. An appropriate frequency domain operator is constructed to eliminate the impact of disturbance. Then, the inverse Fourier transform transforms the frequency domain data in which the disturbance is removed, into time domain data. Finally, an appropriate moving average operator of N items is selected based on spectral characteristics to eliminate the influence of periodic factors and noise.

Through the spectrum analysis of the real-time data sensed and recorded by microwave sensors, the spectral characteristics and the ranges of information, noise and shock disturbance factors in the data can be clarified.

The real-time data analysis results for a drug component monitoring show that the hybrid sequence operator has a good effect on suppressing disturbances, periodic factors and noise implied in the data.

Firstly, the spectral analysis of moving average operator and the novel time-frequency hybrid sequence operator were presented in this paper. For complex data, the ideal effect is difficult to achieve by applying the frequency domain operator or time domain operator alone. The more satisfactory results can be obtained by time-frequency hybrid sequence operator.