Theoretical Phase Research Articles

Effect of a Nutrition Education Intervention on Mothers’ Infant and Young Child Feeding Knowledge and Practices in the Peri-Urban Areas of Bobo-Dioulasso: Before and after Study

Background: This study assessed the effect of a nutrition education intervention aiming to improve the knowledge and practices of under 5 years children’s mothers on infant and young child feeding in peri urban areas of Bobo-Dioulasso in Burkina Faso. Methods: A total of 243 mothers of children under 5 years in the peri-urban of Bobo-Dioulasso were surveyed before and after the intervention using the FAO questionnaire for infant and young child feeding (IYCF) knowledge and practices assessment in January and October 2017. The intervention included two components consisting of a theoretical phase (counselling and discussion) and cooking demonstrations implemented for ten months. To account for the before-and-after design of the study, the McNemar’s test was used to assess the effect of the intervention on mothers’ infant and young child feeding knowledge and practices. Results: The mean age of mothers was 29 ± 6.2 years and 50.6% of the mothers were between 20 and 29 years old. All indicators used to assess the mothers’ knowledge of breastfeeding and complementary feeding significantly improved after the intervention (all p-values Conclusion: The intervention improved the mothers’ knowledge on breastfeeding and complementary feeding and some child feeding practices. This study provided some evidence of an effective nutrition education intervention to increase maternal knowledge and practices.

Experimental Assessment of Generalised Super-Twisting Control for Optimal Reference Tracking in Wave Energy Systems

Maximising wave energy extraction is essential for the successful operation of wave energy converters, and appropriate control strategies play a vital role in achieving this objective. This paper presents a control scheme for an experimental wave energy converter setup. The strategy combines an optimal moment-based reference generation technique with a higher-order sliding mode tracking controller, which provides robust tracking of the associated reference, regardless of the uncertainty present in the experimental operation. The device is tested with two different irregular sea states, and results show that the control structure effectively deals with the system's underlying uncertainty, achieving excellent tracking performance while guiding the system to the corresponding surface following the theoretical phase plot convergence. Furthermore, the comparison with a PID tracking control structure indicates that a proper modification of the tracking element of the loop can improve energy extraction. Finally, consistent tracking error and phase plot evolution behaviour are observed for both sea states.

АНАЛІТИЧНИЙ ОПИС ТЕОРЕТИЧНОГО ЕТАПУ СТВОРЕННЯ ПСИХОЛОГІЧНОГО ІНСТРУМЕНТАРІЮ – МЕТАФОРИЧНИХ АСОЦІАТИВНИХ КАРТ "МАСКА" ДЛЯ РОБОТИ З ВІЙСЬКОВОСЛУЖБОВЦЯМИ (КОМБАТАНТАМИ) ЗБРОЙНИХ СИЛ УКРАЇНИ

The article presents analytical review of theoretical phase of psychological techniques development – metaphorical association cards "Masc" to work with servicemen (combatants) of the Ukrainian armed forces. The main purpose of the tools abovementioned is to increase efficiency of psychological support of servicemen (combatants) of the Ukrainian armed forces (including those who take part in combat actions in the combat area). Metaphorical association cards provide arrangement of constructive dialog between a serviceman and a psychologist that makes possible to optimise time for getting into psychological contact. Metaphorical associational cards are helpful both in performing of psychognosis of servicemen (individually and in groups) promptly and enabling to resolve numerous problems (normalize negative emotional conditions, increase motivation for activity, contribute to resolve conflict situations inside of unit) etc. Use of these cards is more practical because of massive refusals of servicemen to perform tests' tasks with traditional methods of psychognosis, i.e. survey, blank test procedures, computer-based automated psychological procedures, etc. The following results were obtained from theoretical phase of research: 1) peculiarities of metaphorical associational cards were defined, they were recognised as an active psychological tool. Procedure for their employment was determined. Basic recommendations for their development were formed; 2) particularities and advantages of Masc therapy method were defined, and recommendations for it practical use were developed; 3) advantages of both methods combination – Masc therapy method and metaphorical associational cards (MAC) use were established. Creation of psychological tools MAC "Masc" was the result of this research, it is designed for psychological work with servicemen (combatants) of the Armed Forces of Ukraine; 4) the basic list of problems was defined, that is the object to find solution for them by mean of abovementioned psychological tools. It is based on analytical description of part-time groups of psychological aid that accompany Ukrainian Armed Forces units in the battle area from the beginning of full-scale invasion; 5) the procedure for development of metaphorical association cards for psychological work with combatants of Ukrainian armed forces was created.

Development of a complex intervention package for dengue prevention

Introduction: Complex interventions are widely used in public health practices with noteworthy health impacts. Communication for Behavioural Impact (COMBI) plan is an effective method directed at enacting behaviour change to benefit health and social development which encourage precise behavioural outcomes and is effective in planning a behavioural change for dengue control. The aim of this study was to develop an intervention package to change the behaviour to prevent dengue in one of the highest dengue-endemic areas of Sri Lanka.Methods: The development of the intervention package was formulated according to the two phases, the ‘Theoretical phase’ and ‘Modelling phase’ of the framework for ‘Developing and Evaluating Complex Interventions’. World Health Organization’s 10 key steps in planning COMBI strategies were followed in order to develop the present intervention package. A situational market analysis was conducted in the highest dengue-endemic area in Kurunegala district to identify the Specific Behavioural Objectives (SBOO) for the COMBI plan. The development of the COMBI plan was conducted using the mixed methodological approach including quantitative and qualitative designs.Results: The overall goal of the COMBI plan was to decrease the morbidity and mortality due to dengue illness by improving the dengue prevention behaviours among householders. The SBOO for the plan were to improve the proper waste management practices according to the ‘3R concept’ (Reduce, Reuse and Re-cycling) and to improve the dengue prevention practices by 30 minutes of weekly cleaning. The strategies of intervention package were to conduct a community empowerment program to improve household waste management and weekly practices on dengue prevention by conducting administrative mobilization and public relationship, public advocacy, community mobilization, personal selling, advertising, and point of service promotion during follow-up.Conclusion: Developing a COMBI plan for an area after the identification of SBOO would be feasible to implement in order to empower the community to prevent dengue and improve community health services.

Skyrmion and meron ordering in quasi-two-dimensional chiral magnets

We revisit the well-known theoretical phase diagram for a two-dimensional chiral magnet with an easy-axis uniaxial anisotropy and an applied magnetic field. A particular emphasis is given to merons---quanta of the phase transition between the cycloid and the hexagonal skyrmion lattice, which possess fractional topological charges $\ifmmode\pm\else\textpm\fi{}1/2$. A localized state of two coupled merons with opposite topological charges exhibits the nonreciprocal current-driven dynamics: it experiences no skyrmion Hall effect, but due to the asymmetry of the attracting intermeron potential gives rise to asymmetric current-velocity characteristics. We also address the problem of skyrmion ordering into hexagonal and square skyrmion crystals. In an entire field range, the square lattice turns out a saddle point state between differently oriented hexagonal lattices. Merons separating elongated skyrmions were also shown to form a local energy minimum by forming a hexagonal lattice shadowing the ordinary lattice of skyrmions. In addition, we focus on the anisotropy-driven transformations of modulated phases and their isolated counterparts, which exist as detached branches of solutions on both sides from the critical anisotropy value. Moreover, a family of isolated skyrmions with both rotational senses can be found near this anisotropy value. Our results are useful from both the fundamental point of view, since they complement previous findings, and from the point of view of applications, since they provide guidelines for developing meron-based spintronic devices.

Depolymerization of polyethylene terephthalate (PET) under mild conditions by Lewis/Brønsted acidic deep eutectic solvents

Modern society urgently needs new recycling methods to handle the impressive amount of plastic items that are annually discarded. Deep Eutectic Solvents (DESs) have shown interesting results in the depolymerization of polyethylene terephthalate (PET), but most of the procedures still need harsh conditions of temperature and pressure. In this contribution, we propose a bifunctional Lewis/Brønsted acidic DES composed of FeCl3·6H2O, cheap and scarcely toxic, in combination with a variety of acids, both mineral and organic, including some of natural origin (citric and acetic acid). We show that the LBDES formed with methanesulfonic acid and para-toluenesulfonic acid are capable of quantitatively depolymerizing PET under mild conditions, with a temperature of 100 °C and a reaction time of 1 h, affording high purity terephthalic acid in high yield. For acetic acid, a reaction time of 3 h are necessary to obtain a quantitative depolymerization. Different strategies to optimize the PET/LBDES ratio has been successfully tested, as the consecutive addition of multiple aliquots of PET or the filtration and reuse of the solvent.The best solvent has been characterized through the comparison of theoretical and experimental eutectic phase diagram, confirming its nature of DES.

Thermal Hall conductivity with sign change in the Heisenberg–Kitaev kagome magnet

The Heisenberg–Kitaev (HK) model on various lattices has attracted a lot of attention because it may lead to exotic states such as quantum spin liquid and topological orders. The rare-earth-based kagome lattice (KL) compounds and have q = 0, 120° order and canted ferromagnetic (CFM) order, respectively. Interestingly, the HK model on the KL has the same ground state long-range orders. In the theoretical phase diagram, the CFM phase resides in a continuous parameter region and there is no phase change across special parameter points, such as the Kitaev ferromagnetic (KFM) point, the ferromagnetic (FM) point and its dual FM point. However, a ground state property cannot distinguish a system with or without topological nontrivial excitations and related phase transitions. Here, we study the topological magnon excitations and related thermal Hall conductivity in the HK model on the KL with CFM order. The CFM phase can be divided into two regions related by the Klein duality, with the self dual KFM point as their boundary. We find that the scalar spin chirality, which is intrinsic in the CFM order, changes sign across the KFM point. This leads to the opposite Chern numbers of corresponding magnon bands in the two regions, and also the sign change of the magnon thermal Hall conductivity.

Atomic Mechanisms of Cation Adsorption/Exchange in Octahedral Molecular Sieves.

Octahedral molecular sieves (OMSs) based on MnO2 have been widely studied in the fields of deionization, geochemistry, and energy storage due to their microporous tunnel framework capable of adsorbing and exchanging various ions, particularly cations. The understanding of cation adsorption/exchange within OMS tunnels demands atomic-scale exploration, which has been scarcely reported. Here, we disclose how various cations (K+/Ag+/Na+) interplay within the OMS tunnel space on an atomic scale. Not only are the lattice sites for each adsorbed cation species pinpointed but the scenario of dual-cation adsorption within single tunnels is also demonstrated, together with the discovery of characteristic concentration-dependent cation ordering. Moreover, compared with the theoretical parent tunnel phase, the heterogeneous tunnels, though sparsely distributed, exhibit a distinct yet orderly cationic accommodation, highlighting the non-negligible role of tunnel heterogeneity in regulating OMS physiochemistry. Our findings clarify the long-existing ambiguities in nano- and atomic-scale science of the ion adsorption process in OMS materials and are expected to inspire their structural/compositional engineering toward functionality enhancement in various fields.

Delirium in a surgical context from a nursing perspective: A hybrid concept analysis.

The term delirium has been defined in medical diagnosis criteria as a multidimensional disorder, and the term acute confusion is included in nursing classifications. Delirium can be a serious complication assessed in a patient after a surgical procedure. Still, the patient's delirium frequently remains unrecognised. Care of patients with delirium after surgical procedure is complex, and it challenges nursing expertise. From the nurses' viewpoint, delirium is associated with ambiguity of concepts and lack of knowledge. Therefore, reseach on how nurses perceive patients with delirium in a surgical context is needed. The aim of this study was to describe the concepts of delirium and acute confusion, as well as the associated dimensions, in adult patients in a surgical context from the nursing perspective. The study used Schwartz and Barcott's hybrid concept analysis with theoretical, fieldwork, and final analytical phases. Surgical wards, surgical intensive care units, and post-anaesthesia care units. A systematic literature search was performed through Pubmed (Medline), Cinahl, PsycInfo, and Embase. Registered nurses and licensed practical nurses (n=105) participated in the fieldwork phase. In the theoretical phase, the concepts' working definitions were formulated based on a systematic literature search with the year limitations from 2000 until February 2021. At the fieldwork phase, the nurses' descriptions of patients with delirium were analysed using the deductive content analysis method. At the final analytical phase, findings were combined and reported. The concepts of delirium, subsyndromal delirium, and acute confusion are well defined in the literature. From the perspective of the nurses in the study, concepts were seen as a continuum not as individual diagnoses. Nurses described the continuum of delirium as a process with acute onset, duration, and recovery with the associated dimensions of symptoms, symptom severity, risk factors, and early signs. The acute phase of delirium was emphasised, and preoperative or prolonged disturbance did not seem to be relevant in the surgical care context. Patients' compliance with care may be decreased with the continuum of delirium, which might challenge both patients' recovery from surgery and the quality of nursing care. In clinical practice the nurses used term confusion inaccurately. The term acute confusion might be used when illustrating an early stage of delirium. Nurses could benefit from further education where the theoretical knowledge is combined with the clinical practice. The discussion about the delirium, which covers the time both before surgery and after the acute phase should be increased.

Concept analysis of patient safety in home care: a hybrid model

BackgroundPatient safety in home care is a fundamental and complex concept in nursing. This concept includes a number of challenges in patient care. Studies have shown that there is no...

Phase Noise Modeling and Experimental Demonstration of Single and Dual-Loop Direct Modulation Optoelectronic Oscillator

A single and dual loop direct modulation Opto-Electronic Oscillator (DMOEO) phase noise model for generation of low phase noise signal operating in Radio Frequency (RF) and microwave frequency range is proposed and experimentally demonstrated. The distribute feedback (DFB) laser diode is used in the proposed design to perform the RF to optical conversion by exploiting its non-linear transfer function characteristics, in contrast to external modulator in conventional OEO designs. We presented the theoretical phase noise model for single and multi-loop DMOEO deign with all possible noise contributions. Also, simulation scenarios have been demonstrated to show the impact of different noise source on the overall phase noise performance of the OEO. A single and dual loop DMOEO with phase noise of −112 dBc/Hz and −110 dBc/Hz at 10 kHz offset from 2.4 GHz carrier respectively is designed and the side mode suppression better than 50 dB is achieved for the generated signal with 11 dBm output power.

AMPUTATION DUE TO COMPLICATIONS OF DIABETES: NURSING CARE PROTOCOL

Objective: to produce and validate a Nursing care protocol for people amputated due to diabetic complications. Methods: a methodological research study conducted in Recife-PE between February 2019 and October 2020, comprising the following stages: 1) Theoretical phase: integrative literature review; 2) Production phase; 3) Validation by specialists; and 4) Validation by the target population. The Content Validity Index was used in the validation by specialists. The Agreement Index was employed in the validation by the target population. Results: the items included in the instrument permeate the following care dimensions: Biological, Psychological and Socio-educational. Validation by the evaluators was in charge of 13 specialists. The instrument presented an index of 0.94. Validation by the target population was conducted with 33 participants; all the items achieved an agreement index ≥ 80%. Conclusion: the protocol enables comprehensive and humanized care, encouraging autonomy and assisting in rehabilitation; it also allows for a reflection regarding individualization of Nursing care.

School Nurse–Parent Partnership in School Health Care for Children with Type 1 Diabetes: A Hybrid Method Concept Analysis

To define school nurse-parent partnerships in school health care for children with type 1 diabetes (T1D) and determine its attributes using a hybrid model. This method involves a three-phase process: theoretical, fieldwork, and analytical. A literature review was conducted during the theoretical phase. A literature search of articles from January 1991 to February 2020 was conducted using relevant electronic databases. Eighty-three articles that met the inclusion criteria were completely read. Fieldwork data were collected through individual interviews from February to July 2019 in South Korea. In the fieldwork phase, interviews were conducted individually with 22 mothers of students with T1D and 20 school nurses recruited by purposeful sampling. Inductive content analysis was conducted. The findings from the theoretical phase were integrated with those from the fieldwork phase, and the final concept was derived. School nurse-parent partnership in school health care for children with T1D has been defined as an interactive process of maintaining a balanced responsibility and providing tailored care to meet needs by establishing trusting relationships and communicating transparently and openly. This analysis yielded four attributes: trusting relationships, transparent and open communication, balanced responsibility, and providing tailored care to meet needs-this entails providing nursing actions by advocating for students and performing a negotiated role together or individually for student and family. The findings of this study add to the importance of an attribute of balancing responsibility for partnership in school health care. The results show that this partnership could contribute to the development of a scale, theory, and nursing intervention in school health care for children with T1D.

Health misinformation: protocol for a hybrid concept analysis and development

Background: Misinformation represents a serious and growing concern in public health; and has attracted much interest from researchers, media, and the public over recent years. Despite increased concern about the impacts of misinformation on health and wellbeing, however, the concept of health misinformation remains underdeveloped. In particular, there is a need to clarify how certain types of health information come to be designated as “misinformation,” what characteristics are associated with this classification, and how the concept of misinformation is applied in public health interventions. Aim: Developing a shared understanding of what it means for health information to be “misinformation” is an important first step to accurately identifying at-risk groups, clarifying pathways of vulnerability, and agreeing goals for intervention. It will also help to ensure that misinformation interventions are accessible, acceptable, and of benefit to the populations to which they are directed. We will therefore examine the characteristics, measurement, and applications of misinformation in public health. Methods: We will undertake a hybrid concept analysis, following a framework from Schwartz-Barcott & Kim (2000). This framework comprises three phases: a theoretical phase, fieldwork phase, and final analysis phase. In the theoretical phase, a search of seven electronic citation databases (PsycInfo, socINDEX, JSTOR, CINAHL, Scopus, PubMed, and ScienceDirect) will be conducted in order to identify original research, review, and theoretical papers, published in English between 2016 and 2022, which examine “health misinformation.” Data from the literature will be synthesised using evolutionary concept analysis methods from Rodgers (2000). In the fieldwork phase, a purposive sampling strategy will be employed to recruit stakeholders for participation in semi-structured interviews. Interviews will be analysed using thematic analysis. The final phase will integrate findings from the theoretical and fieldwork analyses.

Optimizing Metasurface-Component Performance by Improving Transmittance and Phase Match of the Nanopillars.

In the propagation phase of a dielectric metasurface, there are two important problems. Firstly, the range of transmittance of the nanopillars for a building metasurface is usually between 60% and 100%, which reduces the metasurface's overall transmittance and affects the uniformity of the transmitted light. Secondly, the realistic phase provided by the nanopillar cannot be matched very well with the theoretical phase at each lattice location.The phase difference (between a realistic phase and theoretical phase) may reach tens of degrees. Here, we propose an interesting method to solve these problems. With this new method, a metalens is designed in this paper. The nanopillars for building the metalens have transmittance over 0.95, which increases the metalens transmittance and improves the light uniformity. In addition, with the new method, the phase differences of all elements in the metalens can also be reduced to be below 0.05°, decreasing the metalens spherical aberration dramatically. This method not only helps us to optimize the metalens but also provides a useful way for designing high-quality metasurfaces.

Measurement and development of art therapeutic actions in the treatment of children and adolescents with psychosocial problems

ABSTRACT Background Many childhoods and adolescent psychosocial problems involve dysfunctional emotion regulation. A programme has been developed called Affect regulating Arts Therapies (ArAT) to address emotion regulation problems in children and adolescents. The theoretical concepts and techniques have been described in the ArAT programme, but insight into which specific therapeutic actions contribute to the benefits in clinical practice is still lacking. This study aims to construct a measurement instrument (checklist) to test whether the main therapeutic actions are applied in line with the ArAT programme. Method To develop the measurement instrument, we performed desk research on existing documents and additional literature. In addition, developers were interviewed, and group meetings took place. Finally, to develop the instrument further and investigate the reliability of the measurement instrument, film clips from therapeutic sessions were used and scored by multiple raters. Results Typical therapeutic actions were defined from attachment, trauma, affect-regulating, mentalising, art therapeutic theories and treatments, and could be divided into the three theoretical phases of the ArAT programme: tension regulation, attention regulation, and affect regulation. A first draft item list of 83 items was based on qualitative analysis. In three phases, the draft item list was reduced to 15 items, of which twelve items met reliability criteria. Conclusion The therapeutic core of the ArAT programme lies in enhancing the self-regulatory abilities of children/adolescents through art therapeutic actions that target the regulation of tensions, attention, and affects. The set of 15 items is considered a starting point to further investigate the ArAT programme's treatment integrity. Plain-language summary Many childhoods and adolescent psychosocial problems involve a high sensitivity to emotions and strong emotional reactions to stressful situations, also known as emotion regulation problems. A program has been developed called Affect regulating Arts Therapies (ArAT) to address these problems in children and adolescents. The theory has been described in the ArAT programme, but insight into what the therapist does in this therapy is unclear. This study aimed to create a questionnaire to check whether the main therapeutic actions are applied in line with the ArAT programme. To develop the questionnaire, we searched in existing documents and additional literature. In addition, ArAT developers were interviewed, and group meetings took place. Finally, to develop the questionnaire further and to investigate whether the questionnaire could be completed reliably by different people, film clips from therapeutic sessions were used and scored by multiple people. Typical ArAT therapeutic actions were found in different attachment, trauma, affect-regulating, mentalising, art therapeutic theories and, treatments. They could be divided into the three theoretical phases of the ArAT programme: tension regulation, attention regulation, and affect regulation. The first item list of 83 items was based on literature and interviews. In three phases, this list was reduced to 15 items, of which twelve items could be reliably observed. The therapeutic basis of the ArAT programme lies in improving the child's/adolescents ability to regulate their own emotions through art therapeutic actions. The set of 15 items is considered a starting point to further investigate the ArAT programme's extent to which the intervention is implemented as planned.

Seasonal fluctuations in Baltic sea level determined from satellite altimetry

This study used gridded daily satellite altimetry observations to investigate the spatial variability in the Baltic seasonal sea-level cycle and to assess the main factors that affected its interannual changes during the 1993–2018 period. In addition to the widely studied annual (Sa) and semiannual (Ssa) harmonics, the characteristics of higher frequency oscillations (terannual (three times a year or Sta) and quarterannual (four times a year or Sqa)) were investigated. We demonstrated that the Sa, Ssa, and Sqa harmonics can be reliably identified from gridded daily satellite altimetry data for all regions of the Baltic Sea. The Sta harmonic was reliably identified in all regions except the southeast part of the Baltic Proper and Danish Straits. Low amplitudes and large uncertainties caused by noise in the SLA time series impeded the Sta evaluation in these two regions. In the Baltic Sea, annual oscillations of sea level propagate from the southwest to northeast at a speed of 0.15–0.36 m/s, which is close to the theoretical phase speed of the baroclinic Kelvin wave. The Ssa, Sta, and Sqa oscillations did not demonstrate a statistically reliable spatial variability in the phase. In many regions of the Baltic Sea for the 1993–2018 period, a statistically significant (at the 95% level) increase of +1.3– + 2.2 mm/yr was observed for the amplitudes of the Sa harmonic, while for the amplitudes of the Ssa harmonic, a statistically significant decrease was detected. No statistically significant changes were observed in the amplitudes of the Sta and Sqa harmonics. Wind, atmospheric pressure, and water exchange with the North Sea correlated well with interannual changes in the sea-level seasonal cycle. The air temperature correlated well only with the Sa component. Precipitation, evaporation, and river input were not correlated with seasonal or interannual changes in the sea-level cycle.

Towards Predicting Partitioning of Enzymes between Macromolecular Phases: Effects of Polydispersity on the Phase Behavior of Nonadditive Hard Spheres in Solution.

The ability to separate enzymes, or cells or viruses, from a mixture is important and can be realized by the incorporation of the mixture into a macromolecular solution. This incorporation may lead to a spontaneous phase separation, with one phase containing the majority of one of the species of interest. Inspired by this phenomenon, we studied the theoretical phase behavior of a model system composed of an asymmetric binary mixture of hard spheres, of which the smaller component was monodisperse and the larger component was polydisperse. The interactions were modeled in terms of the second virial coefficient and could be additive hard sphere (HS) or nonadditive hard sphere (NAHS) interactions. The polydisperse component was subdivided into two subcomponents and had an average size ten or three times the size of the monodisperse component. We gave the set of equations that defined the phase diagram for mixtures with more than two components in a solvent. We calculated the theoretical liquid–liquid phase separation boundary for the two-phase separation (the binodal) and three-phase separation, the plait point, and the spinodal. We varied the distribution of the polydisperse component in skewness and polydispersity, and we varied the nonadditivity between the subcomponents as well as between the main components. We compared the phase behavior of the polydisperse mixtures with binary monodisperse mixtures for the same average size and binary monodisperse mixtures for the same effective interaction. We found that when the compatibility between the polydisperse subcomponents decreased, the three-phase separation became possible. The shape and position of the phase boundary was dependent on the nonadditivity between the subcomponents as well as their size distribution. We conclude that it is the phase enriched in the polydisperse component that demixes into an additional phase when the incompatibility between the subcomponents increases.

Influence of ITO layer on laser tolerance of liquid crystal device under continuous-wave laser loading

The laser performance of liquid-crystal devices (LCDs) must be considered because of their applications in laser systems. The phase modulation variation mechanisms, as well as the key absorption factor under continuous-wave (CW) laser loading, remain unclear. In this study, the influence of indium tin oxide (ITO) layers on the laser tolerance of LCDs under CW laser loading was investigated. Comparing the phase modulation variations and thermal effects of passive and active LCDs, the influence of the ITO absorbing layer and the decisive role of temperature on the laser tolerance of the LCDs were confirmed. The results showed that the laser tolerance of the LCD with ITO layers was approximately one-seventh of that of the LCD without ITO layers. ITO layers have proven to be the main absorption factor for active LCDs. However, the variations in phase modulation and morphology under CW laser loading were similar for LCDs with or without ITO layers. The phase modulation variations of the LCDs increased with increasing temperature in the irradiated area. For LCDs with or without ITO, once the CW laser loading induced a similar temperature increase, their phase modulation variations were almost the same. The temperature rise of LCDs is confirmed to be an effective parameter for evaluating the phase modulation degradation of LCDs in high-power CW laser applications. The coincidence between the theoretical and experimental phase modulation variations for LCDs with or without ITO indicates that the temperature-induced refractive index change was the main reason for the LCD phase modulation variation under CW laser loading. These results clarify the basic mechanisms of the phase modulation variation of LCDs under CW laser loading and provide guidance for process optimization and application of LCDs in high-power laser systems.

Integration of BIM in Steel Building Projects (BIM-DFE): A Delphi Survey

This study aims to design a BIM integration model for steel building projects (BIM-DFE). It was developed in the following three phases: (i) theoretical phase, (ii) validation phase, and (iii) statistical analysis for the theoretical phase. A literature review was conducted to study the applications of BIM in steel building projects and to develop an integrated BIM process map for the construction lifecycle of steel buildings. Subsequently, in the validation phase, 32 participants were invited to complete a two-round Delphi questionnaire to validate the BIM-DFE proposal. The participants were classified according to their knowledge level (skilled or expert). Based on the literature review, a process map that integrates BIM in different phases of a steel building project was created. In the first round of the Delphi questionnaire for the validation phase, the various groups studied (skilled vs. expert) were in moderate agreement with the BIM-DFE proposal; however, after the second round, this agreement became better. Therefore, this study contributes to the current body of knowledge by providing a BIM integration model to improve the management of steel building projects as defined by critical stakeholders in the steel industry. In addition, a real-time case is presented to elucidate a part of the research contribution.