Reflection Method Research Articles

Superimposed imaging of acoustic wave reflections for the detection of underground nonmetallic pipelines

Due to the non-conductive and non-magnetic properties, nonmetallic pipelines are difficult to be detected by traditional pipe location technologies. This paper presents a superimposed imaging method of acoustic wave reflections for pipe location, which operates on the propagation of elastic waves. The propagation and attenuation model of elastic waves in soil are constructed according to the geometric relationship between the acoustic source, geophone array and pipelines. The two-dimensional and three-dimensional acoustic field diagrams of underground pipeline are generated by superimposed imaging of the cross-correlation coefficients between the signals from the sound source and geophone array, with the attenuation caused by hysteretic damping and geometric dissipation considered in the imaging process. In order to suppress clutter interference on the imaging results, the strategy of ‘multi-point transmit, multi-point receive and cross-correlation coefficient superposition’ is adopted. In the simulation, comparison is made to demonstrate the influences of different excitation sources on the detection imaging results, including the single frequency signal, multi-frequency signal, Gaussian pulse signal and sweep signal. It is found that the excitation signals with rich frequency components are more conducive to improving the resolution of detection images. The effectiveness of the proposed imaging method is further verified in the experimental work, which may be beneficial for the visualization and determination of the location, depth and orientation of underground non-metallic pipelines.

Electroseismic Scholte‐wave analysis: A potential method for estimating shear‐wave velocity structure of shallow‐water seabed sediments

AbstractThe potential application of conducting Scholte‐wave analysis using electroseismic pressure fields excited by an electric current source due to the electrokinetic effect in fluid‐saturated porous seabed sediments is investigated. First, we develop a numerical modelling algorithm by combining the Luco–Apsel–Chen generalized reflection and transmission method with the peak‐trough averaging method to simulate the electroseismic wave fields in stratified fluid/porous media. The modelling results show that the electroseismic pressure signals recorded on the seafloor are mainly composed of evanescent electroseismic waves, and Scholte waves are the dominant wave pattern. Their amplitudes are generally within the order of magnitudes capable of being detected by current seismic instruments. Then, the modified frequency–Bessel transform method is extended to extract the Scholte‐wave dispersion curves from electroseismic pressure fields. Results demonstrate that Scholte‐wave dispersion curves extracted from electroseismic records are superior to those extracted from conventional seismic wave fields excited by an airgun source under the same source–receiver geometry because they contain many overtones and are almost free from the interferences of dispersive guided waves. Furthermore, the Scholte‐wave dispersion inversion results obtained by employing the Levenberg–Marquardt method show that the shear‐wave velocity model inverted by Scholte‐wave dispersion curves extracted from the electroseismic pressure field is more accurate than those obtained by dispersion curves extracted from the seismic wave fields with the guided‐wave removal. The above results indicate that the electroseismic Scholte‐wave analysis method has the potential to evaluate the shear‐wave velocities of shallow‐water seabed sediments.

Determination of the thickness and optical properties by reflectance method

In this study, we propose a method based on the reflection spectrum envelope to calculate the thickness and optical constants of a semi-transparent thin film deposited on a glass substrate. To validate this method, we compare these optical constants with those obtained from the transmission spectrum in two different thickness cases: one involving a film with a thickness of 700 nm and the other with a thin film of 80 nm. Comparative results of the methods, including well-established approaches such as Swanepoel, Chambouleyron, Sellmeier, Lorentz and Forouhi–Bloomer reveal notable accuracy with RMS errors of 0.21, 0.22, 0.31, 0.36 and 0.38% respectively. In contrast, the “Cauchy” method shows lower precision with a higher RMS error at 0.71%. The method proposed in this study, applied to a film with a thickness of 700 nm, demonstrates the lowest RMS error at 0.17%.

Analysis of stress drop behavior for stick-slip friction based on total reflection observation experiment

This paper employed an experimental system based on the total reflection method to study the contact interface behavior during the stress drop process of stick-slip friction. The two-stage drop behavior was found for the first time, namely, the tangential load during the stick-slip stress drop underwent two successive drops in different rates and magnitudes, instead of a single drop. A critical location at the contact interface, where the contact areas on both sides of this location exhibited different contact behaviors during stress drop events, was found. An image recognition method was present to identify the boundary between the stick and sliding zones of the interface, the impact of stress drop events on interface contact, and the propagation velocity and direction of rupture fronts. Finally, the mechanism for the interesting phenomenon described in this paper was preliminarily discussed. The research may be useful for better understanding the stick-slip friction and its stress drop events.

Identifying factors in the provision of intravenous stroke thrombolysis in Malaysia: a multiple case study from the healthcare providers’ perspective

BackgroundTranslation into clinical practice for use of intravenous thrombolysis (IVT) for the management of ischemic stroke remains a challenge especially across low- and middle-income countries, with regional inconsistencies in its rate. This study aimed at identifying factors that influenced the provision of IVT and the variation in its rates in Malaysia.MethodsA multiple case study underpinning the Tailored Implementation for Chronic Diseases framework was carried out in three public hospitals with differing rates of IVT using a multiple method design. Twenty-five in-depth interviews and 12 focus groups discussions were conducted among 89 healthcare providers, along with a survey on hospital resources and a medical records review to identify reasons for not receiving IVT. Qualitative data were analysed using reflective thematic method, before triangulated with quantitative findings.ResultsOf five factors identified, three factors that distinctively influenced the variation of IVT across the hospitals were: 1) leadership through quality stroke champions, 2) team cohesiveness which entailed team dynamics and its degree of alignment and, 3) facilitative work process which included workflow simplification and familiarity with IVT. Two other factors that were consistently identified as barriers in these hospitals included patient factors which largely encompassed delayed presentation, and resource constraints. About 50.0 – 67.6% of ischemic stroke patients missed the opportunity to receive IVT due to delayed presentation.ConclusionsIn addition to the global effort to explore sustainable measures to improve patients’ emergency response for stroke, attempts to improve the provision of IVT for stroke care should also consider the inclusion of interventions targeting on health systems perspectives such as promoting quality leadership, team cohesiveness and workflow optimisation.

Addressing the Dark State Problem in Strongly Coupled Organic Exciton-Polariton Systems.

The manipulation of molecular excited state processes through strong coupling has attracted significant interest for its potential to provide precise control of photochemical phenomena. However, the key limiting factor for achieving this control has been the "dark-state problem", in which photoexcitation populates long-lived reservoir states with energies and dynamics similar to those of bare excitons. Here, we use a sensitive ultrafast transient reflection method with momentum and spectral resolution to achieve the selective excitation of organic exciton-polaritons in open photonic cavities. We show that the energy dispersions of these systems allow us to avoid the parasitic effect of the reservoir states. Under phase-matching conditions, we observe the direct population and decay of polaritons on time scales of less than 100 fs and find that momentum scattering processes occur on even faster time scales. We establish that it is possible to overcome the "dark state problem" through the careful design of strongly coupled systems.

Облік та оподаткування в інтернет-бізнесі: перспективи розвитку та виклики

Complex economic relationships have a significant impact on consumer opportunities. When using the services of enterprises operating in the field of e-commerce, buyers get the opportunity to save money through more affordable prices and the opportunity to compare the cost of goods, choosing the most profitable ones. This allows them to save time as well, as they can shop from the comfort of their homes, choose the most convenient method of payment and delivery. The Internet opens the market, expands its geography and increases the competition of goods, does not set any restrictions except for access to the network. The article is devoted to the analysis of features of accounting and taxation system in modern Internet business. The impact of digital transformation on accounting and taxation is considered, taking into account the dynamic nature of this sector of the economy. An overview of the current challenges of Internet business in the context of accounting, including the issues of taxation of e-commerce and activities in the online environment, is proposed. In the article, trade in the field of e-business is considered as an object of accounting. An algorithm for conducting trade on the Internet and accounting for settlements with buyers, determining income and financial result is provided. Modern methods of payment for goods are outlined. The methods of reflection in the cost structure of operations related to the creation of a website, the use of a domain and the receipt of hosting services are analyzed. It is proposed to include in the initial cost of intangible assets the costs of website development and domain prolongation, and to reflect the hosting operation as part of sales costs. The rules for the use of cash registers in conducting business transactions in e-commerce, as well as individual cases in which it is not necessary to use cash registers in online stores, are considered. The problematic aspects of normative regulation and accounting of transactions related to e-commerce are highlighted. Recommendations have been developed that can improve taxation in the field of e-commerce – they provide for the improvement of tax administration for entities engaged in e-business.

Development of Standardization Concepts for Packaging Machines

Packaging machines are designed to meet specific customer requirements and are usually produced on a one-off basis. To cater to consumer demands, packaging machines have become more and more complex. This extends the time taken for development and amplifies expenses. Therefore, novel approaches for standardization have to be explored beyond the established applications of mass production.To achieve this, an interdisciplinary value stream analysis is carried out within the relevant departments of a packaging machine company to identify specific constraints and requirements. These requirements are structured and documented to provide a foundation for targeted development of standardization concepts. Additionally, new possibilities are created to evaluate the effectiveness of standardization measures in the future and to establish a continual improvement process.The aim of this project is to establish a comprehensive strategy for standardization, enhanced communication, and data management that will be applied at all operational levels of the company. New communication methods, along with participatory and reflective methods, are expected to enhance acceptance by the employees and optimize business processes.

Benefits and limitations of implementing the ISO 9004:2018 standard

Purpose: The paper's main objective is to indicate the current state of knowledge regarding the results of implementing the ISO 9004:2018 standard, with a particular focus on identifying the potential benefits and limitations of its implementation. The study is in line with the research stream on improving quality management systems and striving for sustainable market success. Design/methodology/approach: The paper is based on a narrative literature review through analysis of the publications available in scientific databases. It was then combined with the method of scientific reflection. Findings: The paper highlights the opportunities that the implementation of the ISO 9004:2018 standard and its integrated self-assessment model offer to organisations. The analysis also revealed limitations associated with the implementation of the standard's recommendations. Practical implications: The research contributes to the development of knowledge in the practical application of the standard and the self-assessment model. It can serve as a reference point for practitioners and scholars interested in the aforementioned subject matter. Originality/value: The originality of the paper lies in its comprehensive analysis of the requirements of the ISO 9004:2018 standard, addressing significant issues both for the academic environment and practitioners in the field of quality management. The study highlights the benefits of applying the self-assessment model, and outlines the challenges associated with its implementation. Keywords: ISO 9004:2018 standard, self-assessment model, quality improvement, sustainable success. Category of the paper: Literature review.

The Nature of Entrepreneurial Training in Selected Agricultural Training Institutions of the Ministry of Agriculture and Livestock in Zambia

This study explored the nature of entrepreneurial education in the selected Agriculture Training Institutions (ATIs) for the Ministry of Agriculture and Live stocks in Zambia. To do this, the study explored Entrepreneurial Education challenges and opportunities in ATIs, widely acknowledged as a transformative tool for job creation in the country. The argument is that if entrepreneurship education is properly enhanced can provide self-reliance in the Zambia’s agriculture sector to attain sustainable socio-economic growth. The aim of the study was to explore the nature of entrepreneurial education in ATIs curricula; identify challenges, opportunities and ways to promote innovation and job creation through the provision of entrepreneurial education in the selected ATIs in Zambia. The study employed a mixed data collection process through purposive sampling procedures. Qualitative data were analyzed thematically while Quantitative data were analyzed using descriptive statistics such as frequencies, percentages, graphs and tables. The findings show that the current ATI curricula and the National Agricultural Policy (NAP) did not adequately address entrepreneurial education in the agriculture sector because they were loosely developed and were production oriented. The study recommended inter alia that ATIs should create curricula that prioritize creativity, and innovation, utilizing blended interactive and reflective teaching methods to support entrepreneurial education.

Reflective optical mirror group assembly process optimization method based on accurate digital twin

The reflective optical mirror group is the core component of precision optical instruments, and their assembly accuracy will directly impact the imaging of optical instruments. In recent years, with the rapid development of digital twin technology in the field of assembly, the application of digital twin to assembly process optimization is currently a research hotspot. This paper proposes an assembly process optimization method for a reflective optical mirror group based on an accurate digital twin model. By accurately simulating the geometrically distributed errors generated by machining and the physical properties of the assembled parts of the reflective optical mirror group during assembly and use, an accurate digital twin model is established to accurately characterize the geometrical and physical properties of the reflective optical mirror group. Using the accurate digital twin modeling method, the mirror deformation and stress distribution of a reflective optical mirror group are accurately predicted, and the main process parameters in the assembly process are optimized according to the prediction results, so that the target value of the imaging phase of the mirror group after assembly is improved by 24%, and the encircled energy is improved by 15.1%. The optimization calculation method proposed in this paper can obtain the optimized assembly process parameters more accurately, and the research results provide effective support for improving the assembly accuracy and performance of optical mirrors and precision digital twin modeling research.

Rapid and portable mid-infrared analysis of wet sediment samples by a novel “filter-press” attenuated total reflectance method

Mid-infrared (MIR) analysis of wet sediments or soils usually requires freezing and drying, adding considerable analysis time and cost, and promoting changes in chemical properties. A novel attenuated total reflectance (ATR) mid-infrared (MIR) method was developed to enable analysis of non-processed, aqueous sediments. Wet sediment samples from the Coorong Lagoon, South Australia, were subjected to laboratory analysis for physical and chemical properties, our new filter-press ATR method, and conventional ATR and diffuse reflectance (DRIFT) analysis of dried samples. For ATR on wet sediments, samples were pressed onto the ATR crystal with a filter-paper backing and scanned. The spectra were analyzed by principal components analysis (PCA) and partial least squares regression (PLSR) to develop multivariate models for total organic carbon (TOC). ATR spectra of as-received wet sediments were poor due to water absorption features, but filter-pressing reduced these and greatly enhanced the solids spectral component. The filter-pressed PLSR cross-validation for TOC resulted in an R2 = 0.89 and RMSECV = 0.78%. Prediction accuracies were similar to freeze-dried ATR samples and far more accurate than testing wet samples without filter-pressing. Our findings confirmed the filter-press ATR method as proof-of-concept and showed that it has the potential to remove one of the major barriers to in-field application of MIR techniques, the high and variable amounts of moisture levels commonly present in many environmental samples. Extension of the filter-press ATR method to a wider range of analytes may enable it to rapidly acquire moist or wet sediment and soil property data while in the field.

Настройка функции временной регулировки чувствительности ультразвуковой аппаратуры по боковому цилиндрическому отражателю при диагностировании деталей подвижного состава

To increase the efficiency of the use of rolling stock, methods and means of technical diagnostics have been developed, which are used during maintenance and repairs, as well as an independent technological process. Diagnosis makes it possible to increase the availability coefficient, the probability of trouble-free operation, repair and control suitability of rolling stock, reduce the cost of its operation and the complexity of technological processes. The complex of test diagnostic measures includes operations of ultrasonic non-destructive testing of railway rolling stock parts and assemblies for the absence of internal unacceptable irregularities. Pulse-echo method, which refers to reflection methods, has become the most wide-spread among ultrasonic control methods. One of the most important operations in the process of ultrasonic testing is to adjust the sensitivity of ultrasonic equipment. The article focuses on the results of a study on the development of a non-etalon method for adjusting the function of temporary sensitivity ultrasonic equipment setting when diagnosing rolling stock parts, taking into account the attenuation of ultrasound along a lateral cylindrical reflector. To implement the method, a new mathematical apparatus has been developed, which is based on the key laws of physical acoustics, as well as the methods of mathematical and physical modeling. The non-standard adjustment of the temporary sensitivity setting function allows to get rid of the disadvantages when using tuning samples with artificial reflectors. A program NDTRT TSA SCR F-BCR has been developed to automate calculations when diagnosing railway rolling stock parts using the ultrasonic method and taking into account the attenuation of the ultrasonic wave along a lateral cylindrical reflector.

Акустические свойства мартенситно-стареющей стали XM-12 после энергетических воздействий

The study of the acoustic properties of maraging steels operated under various energy force and temperature actions is a critical task, since it is the method of acoustic structuroscopy that provides the most reliable connection with the structure, stress-strain state and mechanical properties of steels. The paper is devoted to research of the acoustic properties of the 15-5 PH maraging steel samples under various types of heat treatment under the conditions of mechanical tensile and cyclic loads. Samples of the 15-5 PH maraging steel were studied in three structural states: solid solution annealing and subsequent aging at 470 and 565 °C; during tensile tests; during cyclic tension-compression loading. The research used a unique scientific installation “Information-measuring complex for investigation of acoustic properties of materials and products”. It implements the acoustic mirror-shadow multiple reflections method using electromagnetic-acoustic and piezoelectric transducers based on polyvinylidene fluoride film to excite and receive waves and allows determining the velocity of wave propagation with an error of no more than 2 m/s. The acoustic (wave velocity, elastic moduli, electromagnetic-acoustical (EMA) transformation coefficients, acoustic anisotropy coefficients, acoustoelastic coupling coefficients) and electromagnetic (coercive force and electrical conductivity) characteristics of the samples were examined. The samples were studied in the initial state (before loading); stepwise in the process of tensile loads and subsequent unloading; after tensile tests; during cyclic tension-compression loading. It was revealed that the following acoustic parameters of 15-5 PH steel samples are the greatest structural sensitivity to mechanical tensile load and cyclic loading: transverse wave velocity, Poisson’s ratio, double EMA-transformation coefficient, and acoustic anisotropy coefficient.

Quantitative evaluation of dislocation density in SUS316L utilizing non-contact microwave reflection method

Quantitative evaluation of dislocation density in SUS316L utilizing non-contact microwave reflection method

QUESTÕES DE MÉTODO EM GEOGRAFIA, PELO ESTRABISMO SARTREANO

Method's reflection is revisited owing to the problematic horizon of coloniality that traces scientific Geography, which questions the validity of its tradition in view of the need to re-discuss its bases. The paper resorts to the Knowledge-Existence dialectic, as placed in its práxis by the thought of Jean-Paul Sartre, as a strategy to problematize the epistemological and ontological issues that are involved in the challenges of contemporary Geography. Keywords: Existentialism; Práxis; Coloniality; Epistemology of Geography.

Reframing Assessment Strategies: The Impact of Reflective Teaching on University EFL Lecturers’ Perspectives and Practices

This study delves into the evolving perspectives and practices of lecturers regarding classroom assessment, especially in terms of integrating reflective teaching methods. Drawing insights from 15 English as a foreign language (EFL) lecturers, certain emergent trends were identified, including a pronounced shift towards constructivist approaches to assessment and an increased emphasis on formative over summative assessment strategies. Lecturers also showcased enhanced reflective abilities in assessment design, with a significant number highlighting the improved alignment between learning outcomes, teaching methodologies, and assessment strategies. A deepened appreciation for diverse learning pathways became evident, and there was an amplified responsiveness to student feedback in tailoring assessment strategies. The study also found trends like embracing technological tools for improved assessment, a surge in interdisciplinary collaboration in assessment design, a heightened empathy towards student challenges, and a strong advocacy for collaborative assessments. The findings underscore the profound implications of reflective teaching on assessment strategies. Recommendations for future studies emphasize the need for a broader participant base and exploration of direct impacts on student outcomes.

Strategi Active Learning dalam Pembelajaran Akidah Akhlak: Prinsip dan Urgensi Penerapannya di Madrasah Ibtidaiyah

Madrasah Ibtidaiyah (MI) is a basic/primary education level where at this level, learning should begin to teach students to think actively, creatively, critically, so that they are trained from an early age to apply learning outcomes in their daily lives. Especially in the Aqidah Akhlak lesson, where the direction of achievement of this learning is not just understanding theories in terms of faith and behavior, but until students can apply good behavior as a habit that they carry out every day. Teachers of moral beliefs at the MI level need guidance on how to apply an active learning strategy or method so that learning objectives can be achieved successfully. The aim of this research is to present a discussion about the principles and urgency of implementing active learning strategies in learning moral beliefs for students at the MI level. The research method is library-research, where research data is taken from books and scientific articles from the internet that are relevant to the research discussion. The research results show that learning moral beliefs using an active learning strategy aims to make students more active, interesting and encouraging to attract interest in learning. Active learning can use the basic principles of speaking and listening, reading, writing and reflection methods on students. This strategy is urgent to implement because it can encourage students to become creative individuals in contextualizing the material they receive with their surroundings. In the context of learning moral beliefs, it will provide experience for students so that they are ready to face and answer problems that arise in an era that continues to develop by becoming polite, civilized, moral individuals who have faith and devotion to Allah SWT.

Impact of E–Supply Chain Management on Customer Satisfaction Through Service Quality in Agricultural E-Commerce

The research aimed to assess the impact of applying e-supply chain management (E-SCM) on service quality (SQ) and customer satisfaction (CS) in agricultural e-commerce. It was motivated by challenges in Indonesia that led to foodwaste due to lengthy supply chain, particularly evident in the horticulture category, such as vegetables. The inefficiencies along the chain resulted in substantial annual losses, ranging from IDR 213 to 551 trillion, equivalent to 4% - 5% of Indonesian GDP. Using associative investigation with three variables and 446 samples selected through simple random sampling, the research aimed to evaluate and enhance E-SCM performance in supply chain. The effective applicationof E-SCM offered benefits, including time and cost efficiency, work flexibility, and other conveniences. Not only this did benefit the company but also enhanced service quality and customer satisfaction. SEM-PLS was used with a reflective method, and data processing was facilitated by SMART-PLS 4 software. The results show a significant influence ofE-SCM application on service quality and customer satisfaction. Furthermore, service quality has a significant and direct impact on customer satisfaction. E-SCM influences customer satisfaction through both direct and indirect pathways, which are mediated by service quality variables.

Effectiveness of Increasing Vocabulary and Constructing Sentences for High Class 4/5/6 SDLB for the Deaf Using the MMR Method with Video Media at SLB Riverkids and SLB Putra Jaya

Deafness is a condition where a child experiences problems with his ability to hear. Deaf children have a small vocabulary. The small vocabulary is caused by poor listening skills so that children are unable to accept new vocabulary which results in difficulties in communicating. Apart from difficulties in communication, they also have difficulty in constructing sentences. One step that can overcome the above problem is to apply the Maternal Reflective Method (MMR). The Reflective Maternal Method (MMR) emphasizes the mother's way of teaching language to children, where the teaching is carried out scientifically. The aim of this research is to analyze MMR on the ability of deaf children in adding vocabulary and constructing sentences. This type of research is Quasi Experimental research with a one group pretest posttest design, which applies five pretests and five posttests. Analysis technique for testing hypotheses using the SPSS 25 for Windows program.The research results showed a significant difference between the pretest results and the posttest results. This is proven by the output results obtained p is 0.000, which means p<0.05 then H0 is rejected and Ha is accepted. This means that there is a significant increase in the vocabulary and sentence learning outcomes of deaf students.The conclusion of this research is that the Maternal Reflective Method (MMR) can influence the addition of vocabulary and sentence construction in deaf children