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L. Gǎvruţa (2012) introduced a special kind of frames, named K-frames, where K is an operator, in Hilbert spaces, which is significant in frame theory and has many applications. In this paper, first of all, we have introduced the notion of approximative K-atomic decomposition in Banach spaces. We gave two characterizations regarding the existence of approximative K-atomic decompositions in Banach spaces. Also some results on the existence of approximative K-atomic decompositions are obtained. We discuss several methods to construct approximative K-atomic decomposition for Banach Spaces. Further, approximative _d-frame and approximative _d-Bessel sequence are introduced and studied. Two necessary conditions are given under which an approximative _d-Bessel sequence and approximative _d-frame give rise to a bounded operator with respect to which there is an approximative K-atomic decomposition. Example and counter example are provided to support our concept. Finally, a possible application is given.

An Autodesk Ember three-dimensional (3D) printer was used to print optical components from Clear PR48 photocurable resin. The cured PR48 was characterized by the per cent of light transmitted and the index of refraction, which was measured with a prism spectrometer. Lenses and diffraction gratings were also printed and characterized. The focal length of the printed lenses agreed with predictions based on the thin lens equation. The periodicity and effective slit width of the printed gratings were determined from both optical micrographs and fits to the Fraunhofer diffraction equation. This study aims to demonstrate the advantages offered by a layer-by-layer DLP printing process for the manufacture of optical components for use in the visible region of the electromagnetic spectrum.

A 3D printer was used to print both lenses and diffraction gratings from Standard Clear PR48 photocurable resin. The manufacturing process of the lenses and the diffraction gratings differ mainly in the printing angle with respect to the printer x-y-axes. The transmission diffraction gratings studied here were manufactured with nominal periodicities of 10, 25 and 50 µm. The aim of this study was to optically determine the effective values for the distance between slits, d, and the effective width of the slits, w, and to compare these values with the printed layer thickness.

The normalized diffraction patterns measured in this experiment for the printed gratings with layer thickness of 10, 25 and 50 µm are shown by the solid dots in Figures 8(a)-(c). Also shown as a red solid line are the fits to the experimental diffraction data. The effective values of d and w obtained from fitting the data are compared to the nominal layer thickness of the printed gratings. The effective distance between slits required to fit the diffraction patterns are well approximated by the printed layer thickness to within 14, 4 and 16 per cent for gratings with a nominal 10, 25 and 50 µm layer thickness, respectively.

Chromatic aberration is present in all polymer lenses, and the authors have not attempted to characterize it in this study. These materials could be used for achromatic lenses if paired with a crown-type material in an achromatic doublet configuration, because this would correct the chromatic aberration issues. It is worthwhile to compare the per cent transmission in cured PR48 resin (approximately 80 per cent) to the percent transmission found in common optical materials like BK7 (approximately 92 per cent) over the visible region. The authors attribute the lower transmission in PR48 to a combination of surface scattering and increased absorption. At the present time, the authors do not know what fraction of the lower transmission is related to the surface quality resulting from sample polishing.

There are inherent limitations to the 3D manufacturing process that affect the performance of lenses. Approximations to a curved surface in the design software, the printing resolution of the Autodesk Ember printer and the anisotropy due to printing in layers are believed to be the main issues. The performance of the lenses is also affected by internal imperfections in the printed material, in particular the presence of bubbles and the inclusion of debris like dust or fibers suspended in air. In addition, the absorption of wavelengths in the blue/ultraviolet produces an undesirable yellowing in any printed part.

One of the most interesting results from this study was the manufacture of diffraction gratings using 3D printing. An analysis of the diffraction pattern produced by these printed gratings yielded estimates for the slit periodicity and effective slit width. These gratings are unique because the effective slit width fills the entire volume of the printed part. This aspect makes it possible to integrate two or more optical devices in a single printed part. For example, a lens combined with a diffraction grating now becomes possible.

This paper aims to present a comprehensive review of the laser engineered net shaping (LENS) process in an attempt to provide the reader with a deep understanding of the controllable and fixed build parameters of metallic parts. The authors discuss the effect and interplay between process parameters, including: laser power, scan speed and powder feed rate. Further, the authors show the interplay between process parameters is pivotal in achieving the desired microstructure, macrostructure, geometrical accuracy and mechanical properties.

In this manuscript, the authors review current research examining the process inputs and their influences on the final product when manufacturing with the LENS process. The authors also discuss how these parameters relate to important build aspects such as melt-pool dimensions, the volume of porosity and geometry accuracy.

The authors conclude that studies have greatly enriched the understanding of the LENS build process, however, much studies remains to be done. Importantly, the authors reveal that to date there are a number of detailed theoretical models that predict the end properties of deposition, however, much more study is necessary to allow for reasonable prediction of the build process for standard industrial parts, based on the synchronistic behavior of the input parameters.

This paper intends to raise questions about the possible research areas that could potentially promote the effectiveness of this LENS technology.

Based on an extensive literature review, this chapter outlines key developments in global health and research during the last century with focus on the emergence of violence and child maltreatment as international public health priorities. Violence has been known to humans for millennia, but only in the late 1990s was it recognised as a global public health issue. Every year, an estimated 1 billion children are exposed to trauma, loss, abuse and neglect. Child maltreatment takes a social and economic toll on countries. Research initiated in 1985 found child maltreatment to be associated with increased disease, disability and premature death in adult survivors. The global availability of data on child maltreatment is, however, sporadic with low validity and reliability. Few global experts have consulted and involved the survivors of child maltreatment, as the experts by experience, in their attempts to provide a more comprehensive picture of reality. Youth and adult survivors of child maltreatment are often traumatised by the experience, and it is important to use trauma-informed approaches to prevent re-traumatisation. Participatory and inclusive research on child maltreatment is only in its infancy. There is a need for more inclusive research, designed by survivors for survivors, hereby strengthening local capacity building and informing policymakers from the bottom up. This chapter reviews lessons learnt and provides recommendations for how to enhance the participation and inclusion of the experts by experience in research on child maltreatment.

The purpose of this paper is to directly link information technology (IT) education with real-world phenomena.

The selected objectives are achieved by modeling line of sight (LOS) and nonline of sight (NLOS) mobile channels using corresponding distributions. Within the described experiments, students verify whether modeled generators generate random variables accordingly to the selected distribution. The results of observations are directly compared with theoretical expectations. The methodology was evaluated by students via questionnaires.

The results show that the proposed methodology can help graduate or undergraduate students better comprehend lectured material from mobile communications or mathematical statistics.

The hands on experience using the EMONA system make the approach original.

Among the proposed radio access strategies for improving system execution in 5G networks, the non-orthogonal multiple access (NOMA) scheme is the prominent one.

Among the most fundamental NOMA methods, power-domain NOMA is the one where at the transmitter, superposition coding is used, and at the receiver, successive interference cancellation (SIC) is used. The importance of power allocation (PA) in achieving appreciable SIC and high system throughput cannot be overstated.

This research focuses on an outage probability analysis of NOMA downlink system under various channel conditions like Rayleigh, Rician and Nakagami-m fading channel. The system design's objectives, techniques and constraints for NOMA-based 5G networks' PA strategies are comprehensively studied.

From the results of this study, it is found that the outage probability performance of downlink ordered NOMA under Rayleigh, Rician and Nakagami-m fading channel was good.

Outage probability analysis of downlink ordered NOMA under various channel conditions like Rayleigh, Rician and Nakagami-m fading channels were employed. Though the performance of Nakagami-m fading channel is lesser compared to Rayleigh channel, the performance for user 1 and user 2 are good.

The purpose of this paper is to explore the perceptions of supply chain managers regarding the elements that make up cyber supply chain risk management (CSCRM) and the related level of alignment, to understand how organizations can deploy a CSCRM strategy that goes beyond the technical, internal functioning of single companies and moves beyond the dyad, to create a better alignment that can ultimately lead to improved cyber supply chain resilience.

An exploratory survey in the fast-moving consumer goods (FMCG) industry involving over 100 organizations in Italy was conducted. Results were analysed through one-way analysis of variance, to appraise the differences in the perceptions of the various actors of the FMCG supply chain (Manufacturers, Logistics Service Providers, Retailers).

While a certain degree of alignment of the perceptions across the FMCG supply chain exists, the study found that Logistics Service Providers can play a crucial role as orchestrators of the CSCRM process towards a more “supply chain-oriented” response to cyber threats and risk events. The research also highlights the necessity to see people as key elements for improving cyber resilience in the supply chain.

Through a vertical analysis of a supply chain, the study extends the existing theory on CSCRM, which contains isolated case studies. It also contributes to extending the current theory with the proposal of the paradigm of Logistics Service Providers as orchestrators of the CSCRM process. The study combines different classifications of CSCRM initiatives and embraces theories external to the supply chain literature.

Through the empirical analysis, this study helps practitioners in streamlining the design of cyber security strategies and actions that span across the supply chain for better alignment. This could mean more coordination of efforts and more targeted/accurate investments in CSCRM initiatives. The study invites practitioners to ponder the perceived relevance of the human factor as a source of risk and the perceived importance of countermeasures aimed at mitigating risk events stemming from that source.

By focusing on an entire supply chain, this is one of the first studies on CSCRM that goes beyond the dyad. Its originality also lies in its use of the investigations of perceptions along the supply chain as pillars for the alignment of CSCRM strategies and mitigation initiatives. This original perspective allows for discovering the role of Logistics Service Providers in driving the alignment of the efforts towards better outcomes of the CSCRM process.

This study describes the applicability of the a priori estimate method on a nonlocal nonlinear fractional differential equation for which the weak solution's existence and uniqueness are proved. The authors divide the proof into two sections for the linear associated problem; the authors derive the a priori bound and demonstrate the operator range density that is generated. The authors solve the nonlinear problem by introducing an iterative process depending on the preceding results.

The functional analysis method is the a priori estimate method or energy inequality method.

The results show the efficiency of a priori estimate method in the case of time-fractional order differential equations with nonlocal conditions. Our results also illustrate the existence and uniqueness of the continuous dependence of solutions on fractional order differential equations with nonlocal conditions.

The authors’ work can be considered a contribution to the development of the functional analysis method that is used to prove well-positioned problems with fractional order.

The authors confirm that this work is original and has not been published elsewhere, nor is it currently under consideration for publication elsewhere.

Damage functions constitute an essential part of the modelling of critical infrastructure (CI) performance under the influence of climate events. This paper aims to compile and discuss publications comprising damage functions for transport assets.

The research included the collection of contemplable literature and the subsequent screening for damage functions and information on them. In conclusion, the derived damage curves and formulae were transferred to a unified design.

Damage functions for the transport sector are scarce in the literature. Although specific damage functions for particular transport assets exist, they mainly consider infrastructure or transport in general. Occasionally, damage curves for the same asset in different publications vary. Major research gaps persist in wildfire damage estimation.

The study scope was restricted to the hazards of fluvial floods and wildfires. Despite all efforts, this study did not cover all existing literature on the topic.

This publication summarises the state of the art of research concerning transport asset damage functions, and hence contributes to the facilitation of prospective research on CI performance, resilience and vulnerability modelling.

The aim of this study is to assess healthcare workers' behavior on the congenital hypothyroidism screening program implementation based on a framework protocol and its associated factors.

A cross-sectional study was conducted using the multistage random sampling method in recruiting health clinic workers and purposive sampling techniques for hospital workers. The demographics, providers' characteristic, occupational profile, attitude, perceived behavior control (PBC), knowledge, behavioral intention and adherence to protocol were gathered using validated and reliable self-administered questionnaires.

Partial intention to adhere to protocol was 25.7%. Weak attitude (adjusted odds ratio [AOR]: 5.48, 95% confidence interval [CI]: 3.32–9.06), low PBC score (AOR: 0.91, 95% CI: 0.86–0.95) and low knowledge score (AOR: 0.85, 95% CI: 0.75–0.96) were associated with partial intention to adhere to protocol. In the self-rated adherence assessment, 92.6% of participants from health clinics, 79.1% from pediatric and 61.1% from pathology were found not adhering to protocol. There was a significant association between intention and adherence to protocol.

Documentations and observations in assessing program implementation were limited to perform in the present study. Using self-rated instruments and focusing on healthcare workers alone did not provide a comprehensive assessment.

Availability of a training module at site and regular refreshing course training should be made available to harness knowledge, attitude and behavioral perception in implementing the program activities.

Integrating the Logical Framework Approach in assessing program implementation and application of the Theory of Planned Behavior and Attitude, Subjective Norms, Self-Efficacy Model in this study were beneficial.