Second-order Reflection Research Articles

Realizing highly efficient vertical coupling with dielectric deflective metasurfaces.

Using dielectric deflective metasurfaces, we propose a novel, to the best of our knowledge, out-of-plane modulation scheme to realize vertical coupling on a 220 nm silicon-on-insulator platform. The metasurface is used to deflect vertical incident light to an oblique angle with high efficiency in the cladding layer. This deflection introduces a lateral wave vector component, thus preventing bi-directional transmission of traditional vertical coupling due to the second-order Bragg reflection of the grating. Additionally, an apodized design is employed for the subwavelength grating to improve mode matching with a deflection angle incident. The integration of the metasurface and subwavelength grating enables a new vertical coupling scheme with high efficiency. After global optimization, we achieved a simulation coupling efficiency of -2.19 dB. The measured coupling efficiency is -3.36 dB with a center wavelength of 1545.6 nm and a 1-dB bandwidth of 32 nm. The results confirm the feasibility of the proposed new architecture.

ASSESSING MULTIDIMENSIONAL SCALE OF LOW SELF-CONTROL IN MALAYSIAN PROPERTY CRIMES PRISONERS

The increasing incidence of criminal and delinquent behaviour has received a lot of attention. The Low Self-Control Scale (LSCS) developed by Grasmick et al. (1993) has been significant in our understanding of the role of self-control in that behaviour. The purpose of this study is to look into the psychometric properties of the Malay language modified multidimensional LSCS among 181 property crime convicts in Malaysia prisoner. The validity and reliability of the LSCS second-order reflection measurement model were investigated using the partial least square structural equation modelling (PLS-SEM) method. The findings demonstrate that the six LSCS constructs (temper, easy tasks, self-centered, risk seeking, physicality, and impulsivity), as well as the 23 indicators, can explain the concept of low self-control. This research proved the construct reliability, discriminant validity, and convergent validity of the LSCS’s Malay version. In addition, this research also demonstrated that prisoners disclosed themselves high on each LSCS’s constructs, having the highest ratings on impulsivity and the lowest on temper. In conclusion, the psychometric evidence of LSCS in this study will be catalyzed for future studies of individual self-control in delinquent or criminal behavior.

Propagation of nonlinear surface waves over non-periodic oscillatory bottom profiles

The effect of non-uniform, oscillating bottom profiles on a two-layer stable density stratification model has been examined using the method of weakly non-linear analysis. The study of bottom profiles in the context of two-layered stratified fluids has focused on three specific types: (a) profiles that exhibit a monotonically decreasing pattern, (b) profiles that decay exponentially, and (c) profiles that display Gaussian oscillations. The analysis of the second-order reflection and transmission coefficients for the nonlinear boundary value problem was conducted using a combination of the regular perturbation method and the Fourier transforms technique. The numerical findings pertaining to various physical parameters have been presented, demonstrating the impact of the Class I Bragg resonance in all three profiles and the elevation of the tails in the monotonically decreasing oscillatory profile. Specifically, the presence of high reflections due to the tail-lifting phenomenon is observed in a profile that exhibits a monotonically decreasing pattern, in contrast to the other profiles. The findings of the study indicate that interface modes demonstrate pronounced reflections when the density ratios are low, but divergent results are observed when the density ratios are high. As the density ratio R increases, there is a greater migration of wave energy from the interface mode to the surface mode, resulting in increased levels of reflection. As the value of R approaches 1, it is observed that lower frequencies exhibit significantly more pronounced internal mode reflections compared to surface mode. Several contrasting aspects can be observed in three oscillatory profiles when compared to periodic profiles. These aspects include the disappearance of zero reflection, also known as complete transmission, as well as the presence of oscillations. The findings of this study demonstrate that a monotonically oscillating decreasing profile can be considered as an efficacious Bragg breakwater. Furthermore, this study investigates the energy transfer that occurs during the movement of surface and internal waves across non-periodic oscillatory profiles. As a result, an energy balance relationship is derived, which specifically applies to surface and interface modes. This work has hydrodynamical relevance to wave propagation in coastal regions and to the hydrodynamics of tsunamis in the open ocean, both of which are affected by changes in the bathymetry of the fluid region.

High-performance grating couplers on 220-nm thick silicon by inverse design for perfectly vertical coupling

Efficient grating couplers (GCs) for perfectly vertical coupling are difficult to realize due to the second-order back reflection. In this study, apodized GCs (AGCs) are presented for achieving perfectly-vertical coupling to 220 nm thick silicon-on-insulator (SOI) waveguides in the C-band. We compare the performance of the AGCs to that of uniform GCs (UGCs) and demonstrate the superiority of the former. The AGCs were obtained through inverse design using gradient-based optimization and were found to effectively suppress back reflection and exhibit better matching to the Gaussian beam profile. The design and measurement results show that AGCs have a 3 dB lower coupling loss than UGCs. We fabricated focusing AGCs by electron beam lithography with a single, 70 nm shallow etch and a minimum feature size of 100 nm, which makes them compatible with CMOS technology. The AGCs achieved a coupling efficiency of −5.86 dB for perfectly vertical coupling. Overall, our results demonstrate the potential of AGCs for achieving high-performance coupling in the C-band on the SOI platform.

Downlink Multi-IRS Aided NOMA System With Second-Order Reflection

The performance of non-orthogonal multiple access (NOMA) system can be enhanced by the incorporation of intelligent reflecting surface (IRS), which has the capability of reconfiguring each user’s channel condition according to the demands. In this letter, we aim to design a transmission scheme with low power consumption for downlink multi-IRS assisted NOMA system with the consideration of second-order reflection. To this end, a joint transmit power and phase shift optimization problem is formulated. By leveraging the relationship between the phase shifts and each user’s required transmit power, the joint minimization problem is simplified as a pure phase shift optimization problem. To further address the transformed non-convex problem, a successive phase-rotation method is proposed to determine the phase shifts sequentially. Simulation results show that the proposed scheme performs better than extensive benchmarking schemes in terms of total transmit power.

Optical computation of the Laplace operator at oblique incidence using a multilayer metal-dielectric structure.

We investigate the possibility of the optical computation of the Laplace operator in the oblique incidence geometry using a layered structure consisting of a set of homogeneous thin films. For this, we develop a general description of the diffraction of a three-dimensional linearly polarized optical beam by a layered structure at oblique incidence. Using this description, we derive the transfer function of a multilayer structure consisting of two three-layer metal-dielectric-metal structures and possessing a second-order reflection zero with respect to the tangential component of the wave vector of the incident wave. We show that under a certain condition, this transfer function can coincide up to a constant multiplier with the transfer function of a linear system performing the computation of the Laplace operator. Using rigorous numerical simulations based on the enhanced transmittance matrix approach, we demonstrate that the considered metal-dielectric structure can optically compute the Laplacian of the incident Gaussian beam with the normalized root-mean-square error of the order of 1%. We also show that this structure can be effectively utilized for optical edge detection of the incident signal.

Objectivity of scientific reflection

The article focuses on scientific reflection. The transcendental reflection does not analyse the content of knowledge, but reveals its conditions and is a condition of scientific research. This is not only thinking about thinking, but also the operations of identifying and distinguishing sensory data, and the rules for structuring the universe. The selection of input data depends on objective cognitive operations. Reflection reveals possible ways of transforming nature. Different forms of reflection achieve different goals. Reflection as a metatheory builds a fundament for future science. The analysis of cognitive procedures reveals the privileged status of classical theory and possible ways of creating non-classical theories. The classical theory is the original theory from which the non-classical ones are derived. Correspondently, scientific knowledge is divided into initial and derived forms. Derived forms are established by second-order reflection. Thus, the objective structure of science is conditioned by the structure of the reflexive activity of the mind.

Methods for Simplifying Quasi-Deterministic Millimeter-Wave Channel Models

It is crucial to have a dependable and precise channel model in order to study the properties of millimeter wave (mmWave) propagation. The Quasi-deterministic (QD) channel model is employed in this viewpoint, which describes the propagation of mm-Wave as a group of reflected and scattered rays originating from a complex environmental setup. These rays are assumed to travel in clusters, with each cluster consisting of a deterministic ray followed by postcursor rays and preceded by precursor rays. The summation of these rays is the number of multiple path components (MPCs) of each cluster. However, this comes at the cost of higher computational complexity for the channel model, which can hinder the simulation’s scalability. To simplify the QD channel model while maintaining accuracy, one option is to decrease the number of MPCs. In this paper, we present an analysis of path gains (PGs) of specular and diffused rays to reduce the total number of MPCs. Specifically, we propose two different reduction methods namely: i) the reduced post rays (RPR) method ii) the removed surfaces post rays (RSPR) method. The computational performance of the proposed methods is investigated in terms of computational time, and complexity. Additionally, the accuracy validation compared to the original QD model is evaluated in terms of PG cumulative distribution function (CDF), signal-to-noise ratio (SNR), and intra-cluster statistics. The proposed methods’ complexity and accuracy were assessed by examining measured data from indoor and outdoor environments at 60 GHz and 28 GHz, respectively. Both first and second-order reflection orders were tested to illustrate the balance between the two variables. The simplified methods suggested can decrease computational time by approximately 16% and 11% for RSPR and RPR schemes, respectively, when compared to the original QD.

REFLECTION IN SECOND-ORDER SET THEORY WITH ABUNDANT URELEMENTS BI-INTERPRETS A SUPERCOMPACT CARDINAL

Abstract After reviewing various natural bi-interpretations in urelement set theory, including second-order set theories with urelements, we explore the strength of second-order reflection in these contexts. Ultimately, we prove that second-order reflection with the abundant atom axiom is bi-interpretable and hence also equiconsistent with the existence of a supercompact cardinal. The proof relies on a reflection characterization of supercompactness, namely, a cardinal $\kappa $ is supercompact if and only if every $\Pi ^1_1$ sentence true in a structure M (of any size) containing $\kappa $ in a language of size less than $\kappa $ is also true in a substructure $m\prec M$ of size less than $\kappa $ with $m\cap \kappa \in \kappa $ .

Graphical acoustic computing method incorporated with the shooting and bouncing ray: application to target strength prediction of concave objects with second-order reflection effects

The acoustic backscattering prediction of underwater targets has been drawing concerns from underwater vehicle designers. A graphical acoustic computing method combined with the shooting bouncing ray method (GRACO-SBR) is introduced to solve the acoustic target strength of complex underwater target with concave surfaces. The graphical acoustic computing (GRACO) is an asymptotic method based on physical acoustics. Aided with OpenGL 3D graphical rendering pipeline, this method can process the acoustic integration parallelly and efficiently. Since the traditional GRACO only considers the first-order scattering, the shooting and bouncing ray (SBR) is compounded with the GRACO to cope with the higher-order scattering of concave structures. The target strength of an impedance sphere is solved with several different methods including the GRACO. The results show that the GRACO has an outstanding advantage of the efficiency over the finite element method (FEM) and the traditional Kirchhoff approximation at minor cost of the accuracy in high frequency range. Besides, the prediction of the backscattering of a dihedral corner reflector tells that the GRACO-SBR which considers the second-order scattering can acquire much more accurate solutions than the traditional GRACO method. Further, a stern with cross rudders is considered by both GRACO and GRACO-SBR, and the solutions show that the second-order scattering cannot be overlook when predicting the backscattering of concave structures.

Second-order approximate reflection coefficients of vertical transversely isotropic thin beds

Second-order approximate reflection coefficients of vertical transversely isotropic thin beds

How can critical reflection be promoted in professional learning communities? Findings from an innovation research project in four schools

This article presents findings from an innovation research project titled School-In, focusing on school staff’s reflection. Teachers in four schools participated in focus group discussions in the beginning and at the end of the innovation. Wackerhausen’s theory is used to understand reflection and how it develops in professional learning communities. Findings from the study indicate: (1) in the beginning of the innovation, reflection mainly of first order – focusing on how things are or should have been, and (2) at the end of the innovation, reflection mainly of second order – critical reflection on the school’s practices. Change is promoted by use of different reflective work forms in mixed groups, focusing on collective capacity and common expectations. The innovation releases teachers’ knowledge and experiences, enabling them to carry out second-order reflection and to critically analyzing their personal and the school’s practice.

Reflection principles and second-order choice principles with urelements

We study reflection principles in Kelley-Morse set theory with urelements (KMU). We first show that First-Order Reflection Principle is not provable in KMU with Global Choice. We then show that KMU + Limitation of Size + Second-Order Reflection Principle is mutually interpretable with KM + Second-Order Reflection Principle. Furthermore, these two theories are also shown to be bi-interpretable with parameters. Finally, assuming the existence of a κ+-supercompact cardinal κ in KMU, we construct a model of KMU + Second-Order Reflection Principle where Limitation of Size fails.

Revolution or Rejection?

Mark S. Massa’s The Structure of Theological Revolutions: How the Fight Over Birth Control Transformed American Catholicism is a study on two levels. On one level, it is a study of the responses of select American moral theologians to Pope Paul VI’s 1968 encyclical on contraception, Humanae vitae (hereafter, HV). On another level, it is a second-order reflection on these theological responses, using them as data, as it were, for a theory about how theology changes or does not change over time. The book certainly succeeds on the first level. I am not sure, however, that that success translates easily to the second level. To the extent that it is possible, I would like to work with these levels successively, even if, for Massa, the two are accomplished simultaneously, since the narration of the “brilliance” (passim) of the individuals treated is tied to the narration of how each of them radically broke with the paradigm of natural law that Massa claims is enshrined in HV.

The Three Pillars of Functional Autonomy of Hackers

We propose a conceptual framework for analysing the relationship between social emancipation and alternative technology development. Key is the “functional autonomy” of the collective of users and developers of the technology vis-a-vis state and capital. We draw on previous empirical work about three hacker projects to substantiate the claim that the functional autonomy of hackers rests on three “pillars of autonomy”: technical skill, shared values, and collective memory. These three pillars sustain the autonomy of a community of hackers so that it may successfully resist recuperation attempts by capital. We make this claim in contradistinction to looser constellations of users, citizen scientists, DIY hobbyists, etc., where the functional autonomy tends to be much weaker. Hence, in the latter case, we should expect the actors to be recuperated in short time. The emancipatory promises that they make in regard to their practices, and are often mirrored in the academic literature about user innovation, citizen science, etc., will then turn sour. From this observation, we develop a second-order reflection on the role of the scholar studying purportedly emancipatory technology projects. As against the popular “follow-the-actors” approach, we defend the continued need for scholarly critique. We do so with the caveat that critique must in part be conducted as self-critique.

Nonlinear signal errors in homodyne laser Doppler vibrometry induced by strong second-order ghost reflections and their mitigation.

A variety of mechanisms can induce distortions in the output signals of a homodyne laser Doppler vibrometer (LDV). In this paper, the nonlinear LDV distortions caused by a strong second-order ghost reflection originating from lens flares are theoretically explained and analyzed. We propose a simple compensation method to mitigate this distortion. The performance and limitations of this method are also explained both in simulation and in experiment.

Babel in Russian and Other Literatures and Topographies: The Tower, the State, and the Chaos of Language. Martin Meisel. Lanham, MD: Lexington Books, 2019. Pp. xx+148.

<i>Babel in Russian and Other Literatures and Topographies: The Tower, the State, and the Chaos of Language</i>. Martin Meisel. Lanham, MD: Lexington Books, 2019. Pp. xx+148.

A modified mixed domain method for modeling acoustic wave propagation in strongly heterogeneous media.

In this paper, phase correction and amplitude compensation are introduced to a previously developed mixed domain method (MDM), which is only accurate for modeling wave propagation in weakly heterogeneous media. Multiple reflections are also incorporated with the one-way model to improve the accuracy. The resulting model is denoted as the modified mixed domain method (MMDM) and is numerically evaluated for its accuracy and efficiency using four distinct cases. It is found that the MMDM is significantly more accurate than the MDM for strongly heterogeneous media, especially when the phase aberrating layer is approximately perpendicular to the acoustic beam. Additionally, a convergence study suggests that the second-order reflection could be sufficient for cases involving high contrast inhomogeneities and large loss values (e.g., skulls). The method developed in this work could facilitate therapeutic ultrasound for treating brain-related diseases and disorders.

СУЩЕСТВОВАНИЕ АВТОРСКОГО ТЕКСТА В КОНТЕКСТЕ ПОНИМАНИЯ ПЛАТОНОВСКИХ ЭЙДЕСОВ

This article is devoted to the study of musical text in the context of the Plato ontology. Our task is to show the process of cognitive comprehension of a musical text as an ontological and hermeneutic reflection. It is fundamentally important for the author to become acquainted with two basic philoso-phical positions, showing fundamentally opposite views on the musical ontology as a whole. To reveal the existence of a musical text at the ontological and hermeneutic levels, we need to develop the neces-sary tools to “subtract” the authentic meanings that underlie the creation of the creator of the text. In the context of the problem under study, we will get acquainted with the various ontological positions of philosophers such as Peter Kivy, Jerome Levinson and other thinkers. Observing, for example, the invisible controversy of Kiwi and Levinson, we can track two radically opposite approaches to the study of musical text. Developing the position of classical Platonism that musical compositions are discovered rather than created, Peter Kivy shows us musical works as discovered eternal types. The opposite position is that of Jerome Levinson, showing a musical composition as a soluble idea, which lies in the potentiality of the author. This approach criticizes the idea of combining musical creations with Platonic universals (Kivy), arguing, on the contrary, about the author’s onto-logical principle. Choosing one of the approaches to understanding the authentic intent of the author’s text, we need to establish the primary and secondary levels of reflection. Given the direct relationship between the author and the interpreter of the text, it is important for us to identify the ontological conditions for the emergence of the text as the primary level of reflective immersion. The level of hermeneutic exist-ence, which implies the conditions and variability of the musical variant of the text, we will attribute to second-order reflection. Thus, in the context of the Plato ontology, it is important for us to identify the uniqueness of the historical text and show the self-existence of its existence. In this regard, the author comes to the con-clusion that the moment of birth of the text is in intuitive experience as an eternal idea that does not depend on anything and does not go anywhere. This level is the most basic, since the fact of fixing the idea of the text in direct graphics is secondary, and having recognized the graphics, the transcriptor creates the interpretation-thing of the idea, just trying to establish similarity as the principle of com-munication. An attempt to establish this connection in the form of a musical interpretation is multivari-ate and coincides with the original idea only partially. As a result, at the hermeneutic level, scoring of musical notations enlivens the musical being of the text, but at the same time alienates us from under-standing its original idea.

SVM-Assisted Realization and Demonstration of Indoor 4 Mb/s Non-Line-of-Sight Visible Light Communication With Second-Order Reflection

Non-line of sight (NLOS) visible light communication (VLC) from reflections can expand the application beyond the line-of-sight (LOS) link. We demonstrate the experimental results on such indoor NLOS VLC, up to the second-order reflection. We employ an avalanche photodiode (APD) receiver due to the strong ambient light background. Manchester coding is adopted at the transmitter, and digital filtering is adopted at the receiver. We propose an Support Vector Machine (SVM) detection method to solve the significant distortion issue due to weak signal of the NLOS link. Experimental results on the second-order reflection-based VLC demonstrate that the detection error probability of the proposed SVM detection can be reduced up to at least two orders of magnitude compared with the Gaussian approximation-based detection, and can reach $10^{-4}$ at bit rate 4Mbps. Thus, low-data rate applications can be achieved by VLC with only the second-order reflection, which implies the potential in speech/image/control message transmission and Internet of Things (IoT) applications, for example the mobile robots that may operate in the shadow or even under a table. Experimental results on the second-order reflection at different transmission rates, different sampling rates, different AC signal amplitudes, and different DC voltages of bias-tee are also demonstrated.