Reflection Model Research Articles

Providing care during a breech birth

A student midwife, Eowyn Robinson, provides a critical reflection of an experience providing care during a breech birth, exploring the situation using the holistic reflection model

Investigation into the reflection properties of the neutron star low-mass X-ray binary 4U 1636–53

We present the spectroscopy of the neutron star low-mass X-ray binary 4U 1636–53 using six simultaneous XMM-Newton and Rossi X-ray Timing Explorer observations. We applied different self-consistent reflection models to explore the features when the disk is illuminated by either the corona or the neutron star surface. We found that the spectra could be well fitted by these two types of models, with the derived emissivity index below a typical value of 3. The relative low emissivity can be explained if the neutron star and the corona, working together as an extended illuminator, simultaneously illuminate and ionize the disk. Additionally, the derived ionization parameter in the lamppost geometry is larger than the theoretical prediction. This inconsistency likely suggests that the corona does not emit isotropically in a realistic context. Furthermore, we also found that there is a possible trend between the height of the corona and the normalization of the disk emission. This could be understood either as a variation in the reflected radiation pressure or in the context of a jet base. Finally, we found that the disk is less ionized if it is illuminated by the neutron star, indicating that the illuminating source has significant influence on the physical properties of the disk.

Cloud reflection modelling for impact flashes on Jupiter

Aims. We investigate the optical characteristics of flashes caused by the impact of metre- to decametre-sized outer Solar System objects on Jupiter, and the contributions of reflected light from surface clouds at visible wavelengths, in order to estimate more accurate bulk parameters, such as the luminous energy of the flash, the kinetic energy, the mass, and the size of the impact object. Methods. Using the results of recent reflectivity studies of the Jovian surface, we developed a cloud reflection model that calculates the contribution of the reflected light relative to that directly from the flash. We compared the apparent luminous energy of the previously reported flashes with the expected cloud reflection contributions to obtain their revised bulk parameters. Results. We find that cloud reflection contributions can make up to 200% of the flux directly from the flash, and thus can be the most significant uncertainty in the measurement of the bulk parameters. The reflection contributions strongly depend on wavelength. With our cloud reflection correction, we obtained revised bulk parameters for the previously reported flashes. Conclusions. Our cloud reflection correction enables us to better understand the properties of objects impacting Jupiter and is crucial for ongoing detailed investigations using high-sensitivity and multi-wavelength observation systems, such as PONCOTS. It will also be useful for understanding other optical transients in Jupiter’s upper atmosphere, such as the recently discovered sprite-like events.

Constraining the White-dwarf Mass and Magnetic Field Strength of a New Intermediate Polar through X-Ray Observations

We report timing and broadband spectral analysis of a Galactic X-ray source, CXOGBS J174517.0−321356 (J1745), with a 614 s periodicity. Chandra discovered the source in the direction of the Galactic Bulge. Gong proposed that J1745 was either an intermediate polar (IP) with a mass of ∼1 M ⊙, or an ultracompact X-ray binary (UCXB). To confirm J1745's nature, we jointly fit XMM-Newton and NuSTAR spectra, ruling out a UCXB origin. We have developed a physically realistic model that considers a finite magnetosphere radius, X-ray absorption from the preshock region, and reflection from the white-dwarf (WD) surface to properly determine the IP properties, especially its WD mass. To assess systematic errors on the WD mass measurement, we consider a broad range of specific accretion rates ( g cm−2 s−1) based on the uncertain source distance (d = 3–8 kpc) and fractional accretion area (f = 0.001–0.025). Our model properly implements the fitted accretion column height in the X-ray reflection model and accounts for the underestimated mass accretion rate due to the (unobserved) soft X-ray blackbody and cyclotron cooling emissions. We found that the lowest accretion rate of = 0.6 g cm−2 s−1, which corresponds to the nearest source distance and maximum f value, yields a WD mass of (0.92 ± 0.08)M ⊙. On the other hand, as long as the accretion rate is g cm−2 s−1, the WD mass is robustly measured to be (0.81 ± 0.06)M ⊙, nearly independent of . The derived WD mass range is consistent with the mean WD mass of nearby IPs. Assuming spin equilibrium between the WD and accretion disk, we constrained the WD magnetic field to B ≳ 7 MG, indicating that it could be a highly magnetized IP. Our analysis presents the most comprehensive methodology for constraining the WD mass and B field of an IP by consolidating the effects of cyclotron cooling, finite magnetospheric radius, and accretion column height.

PENGARUH MODEL PEMBELAJARAN INTRODUCTION CONNECTION APPLICATION REFLECTION DAN EXTENSION (ICARE) TERHADAP KEMAMPUAN PEMECAHAN MASALAH DAN KEMAMPUAN BERPIKIR KRITIS SISWA PADA MATERI ARITMATIKA SOSIAL DI KELAS VII SMPIT DARUL FIKRI BENGKULU UTARA

This study aims to determine the effect of the Intruction Connection Application Reflection and Extention (ICARE) Learning Model on Students' Problem-Solving Ability and Critical Thinking Ability. This type of research uses the Quasi Experiment method. Data collection is done through tests. Data analysis used the Ancova test. The sample of this study were students of SMPIT Darul Fikri Bengkulu Utara grades VII A and VII B. The results showed that: 1) There was a linear covariate effect of initial ability on problem solving ability with a significant influence of 50.3%. 2) There is a linear influence of the initial ability covariate on critical thinking skills with a large influence of 56.7%. 3) There is an effect of learning using the ICARE model on students' problem-solving abilities with a large influence of 59.9%. 4) There is an influence of learning using the ICARE model on students' critical thinking skills with a large influence of 59.4%.

Diffuse Reflection Effects in Visible Light Positioning: Analysis, Modeling, and Evaluation

Currently, the Global Positioning System (GPS) is widely used, but its signal is attenuated by factors such as trees, walls, and ceilings, which severely degrade its positioning accuracy. To fill the gap, various indoor positioning techniques have attracted increasing attention in recent years. Visible light positioning (VLP) is a promising scheme for indoor positioning due to its high precision, high security, and low energy consumption; however, ubiquitous diffuse reflection affects the accuracy and robustness of VLP. During our testing, we found that diffuse reflection could increase the error in RSS values by 20~30%, severely affecting VLP accuracy; however, diffuse reflection is inevitable in real positioning environments. To solve this problem, this paper first establishes a wall diffuse reflection model and then implements a visible light positioning system based on an Internet of Things platform. Finally, this paper uses the system to verify the effectiveness of the diffuse reflection model. The experiments show that the proposed model effectively improves positioning accuracy by 36.7~61.3%.

Testing Physical Scenarios for the Reflection Features of Type-1 AGNs using XMM-Newton and NuSTAR Simultaneous Observations

Above ∼3 keV, the X-ray spectrum of active galactic nuclei (AGNs) is characterized by the intrinsic continuum and Compton reflection features. For type-1 AGNs, several regions may contribute to the reflection. To investigate the nature of the reflecting medium, we perform a systematic analysis of the reflector using XMM-Newton and Nuclear Spectroscopic Telescope Array observations of a sample of 22 type-1 AGNs. We create a baseline model that includes Galactic absorption and an intrinsically absorbed power law, plus a reflection model. We test a set of nine reflection models in a subsample of five objects. Based on these results, we select three models to be tested on the entire sample, accounting for distinct physical scenarios: neutral/distant reflection, ionized/relativistic reflection, and neutral/distant+ionized/relativistic reflection, namely, a hybrid model. We find that 18 sources require the reflection component to fit their spectra. Among them, 67% prefer the hybrid model. Neutral and ionized models are equally preferred by three sources. We conclude that both the neutral/distant reflector most probably associated with the inner edges of the torus and the ionized/relativistic reflector associated with the accretion disk are required to describe the reflection in type-1 AGNs.

A virtuous cycle of co-production: Reflections from a community priority-setting exercise.

Co-production is gaining increasing recognition as a good way of facilitating collaboration among different stakeholders, including members of the public. However, it remains an ambiguous concept as there is no definitive or universal model of co-production or clarity on what constitutes a good co-production approach. This paper draws on the reflections of the academic researchers, practitioners and public advisors involved in co-producing a priority-setting exercise. The exercise was conducted by the Primary and Community Health Services (PCHS) Theme of the National Institute for Health and Care Research Applied Research Collaboration for Kent, Surrey and Sussex (NIHR ARC KSS). We collected data through written and verbal reflections from seven collaborators involved in the PCHS priority-setting exercise. We used Gibbs' model of reflection to guide the data collection. We then analysed the data through an inductive, reflexive thematic analysis. A common thread through our reflections was the concept of 'sharing'. Although co-production is inherently shared, we used the virtuous cycle to illustrate a sequence of sharing concepts during the research cycle, which provides the underpinnings of positive co-production outcomes. We identified six themes to denote the iterative process of a shared approach within the virtuous cycle: shared values, shared understanding, shared power, shared responsibilities, shared ownershipand positive outcomes. Our results present a virtuous cycle of co-production, which furthers the conceptual underpinnings of co-production. Through our reflections, we propose that positive co-production outcomes require foundations of shared values and a shared understanding of co-production as a concept. These foundations facilitate a process of shared power, shared responsibilitiesand shared ownership. We argue that when these elements are present in a co-production exercise, there is a greater potential for implementable outcomes in the communities in which the research serves and the empowerment of collaborators involved in the co-production process. Three members of the public who are public advisors in the NIHR ARC KSS were involved in the priority-setting exercise that informed this paper. The public advisors were involved in the design of the priority-setting exercise and supported participants' recruitment. They also co-facilitated the focus groups during data collection and were involved in the data analysis, interpretation and preparation of the priority-setting report. For this current manuscript, two of them are co-authors. They provided reflections and contributed to the writing and reviewing of this manuscript.

Teaching Squares

The Teaching Squares Program involves the formation of a 3- or 4-member group of educators from different departments or disciplines. The diversity in knowledge and experience helps to promote cross-disciplinary learning and professional growth among teachers. Once the group has been formed, the teachers select a class they will each teach during the observation phase. Other teachers observe each instructor as they lead the students and engage with them. Participants then meet after they make their observations to provide feedback. The teachers meet regularly to provide feedback in a supportive and constructive manner.
 The Teaching Squares Program helps to promote continuous professional growth and development. As teachers observe their peers, they learn practical strategies that their peers use to encourage a collaborative and supportive learning environment. A significant benefit of Teaching Squares is that faculty can observe and learn from their colleagues. In this program, teachers observe their colleagues in the teaching process and give feedback using given criteria. Teaching Squares allows teachers to receive feedback on their teaching approach and strategies from their peers. The program encourages the teachers to reflect on their practice and seek practical opportunities for development and growth. This program is a multidisciplinary model for instructor reflection and assessment. Furthermore, Teaching Squares provides a sense of togetherness and collaboration among faculty members.
 Usually, teachers devote much of their time to preparing lessons, teaching, and assessing students, leaving them with little time to observe and learn from colleagues. Teaching Squares is a structured program that allows teachers to observe and learn from their colleagues. It is a practical approach that can help improve their performance and effectiveness. This is a peer review process that allows collaboration and reflection among faculty members. Teaching Squares is a structured program that involves approximately 3 to 4 faculty members who observe their colleagues in the teaching process and give feedback using given criteria. The program aims to provide faculty with a platform to observe and learn from each other's teaching approaches in a non-competitive and supportive environment. The participating members follow the teaching process of their colleagues and then offer helpful feedback as they engage in reflective discussions.

Developing student-centred perspectives in PBL: how teacher profiles reveal educational needs for faculty development programmes

BackgroundIn Asian higher education, PBL is not always successful, as few teachers have embraced a student-centred perspective. To cultivate such essential perspectives, faculty development programmes should address teachers’ specific educational needs, which sadly is currently not sufficiently the case. This study aimed to identify teacher profiles that would reveal these specific educational needs of teachers and to investigate the relationship between these profiles and the amount of PBL training previously received.MethodsTo identify the said profiles, we performed latent profile analysis on a stratified random sample of 543 teachers based on a survey of teaching perspectives on the six aspects of Korthagen’s onion model of reflection (environment, behaviour, competencies, beliefs, identity and mission). Additionally, we employed Chi-square and Mann-Whitney tests to investigate the aforementioned relationship.ResultsWe identified six teacher profiles that resemble the diffusion of innovations theory’s classification of innovation adopters: Innovators, Early adopters, Early majority 1, Early majority 2, Late majority and Laggards. The Chi-square test demonstrated that the amount of PBL training received did not differ significantly across profiles, although teachers with a more innovative profile had undergone slightly more PBL training. The Mann-Whitney test furthermore revealed for three profiles that more PBL training was associated with a higher overall score for student-centredness. When aspects were considered separately, however, this was not the case.ConclusionsThe findings confirmed that current faculty development programmes are not sufficiently tailored to teachers’ needs. We therefore propose that faculty development programmes be redesigned to address teachers’ specific educational needs as reflected in the profiles based on the 6 aspects of the onion model. We expect such a tailored approach to more effectively promote the development of student-centred perspectives.

Teachers as Learning Leaders at SMKN 5 Lhokseumawe

The teacher is a professional with his main task of teaching, guiding, training and educating students. In the learning process in the classroom, the teacher is the real leader who manages the classroom environment to achieve learning goals. The teacher is a reflection and role model for students, the attitudes and actions of a teacher can determine the continuity of the learning process to achieve learning goals. This study aims to find out how the competence of teachers as learning leaders at SMKN 5 Lhokseumawe. This study used a qualitative research approach, namely a descriptive survey method. The results of the study showed that: teacher competence as a learning leader at SMKN 5 Lhokseumawe in implementing learning takes place in a conducive manner, because teachers have competence as leaders and This application already exists in the learning system. This can be seen from the teachers who are 87% already have the ability to become a leader and make the class active in the learning process. In addition, teachers at SMKN 5 Lhokseumawe also have skills as learning leaders in class, and meet competency standards as educators, both pedagogical competence, attitude competence, professional competence and individual competence and have a personality in accordance with the teacher's code of ethics that applies in the type law -Types of behavior of educators.

Photonic Characterization and Modeling of Highly Efficient Color Conversion Layers With External Reflectors

We propose a new method for fabricating arrays of colloidal quantum dots for color conversion layers (CCLs) with atomic layer deposited (ALD) encapsulation. Semiconductor processes were used to transfer the CCL onto a transparent glass substrate. This method enables pixels as small as 5 μm, and the pixel's size and pitch can be controlled through the semiconductor process and mask layout. A dual-color array with a red-and-green CCL was also demonstrated to be suitable for microdisplay applications in experiments. The best color conversion efficiency of a single color CCL reached as high as 20.7%. A set of distributed Bragg reflector mirrors was used to increase photon recycling, and these mirrors yielded an increase in peak intensity of 35.7%. We formulated a model of incoherent reflection and transmission to calculate the changes in CCL properties when mirrors are added; this model had close fit with results from experiments in which mirrors of different reflection coefficients were used. Through the use of ALD, the CCL can be stored at a normal room-temperature environment for more than 9000 hours, and the projected lifetime is linearly extrapolated to be 44,041 hours.

MUTE: A multilevel-stimulated denoising strategy for single cataractous retinal image dehazing.

In this research, we studied the duality between cataractous retinal image dehazing and image denoising and proposed that the dehazing task for cataractous retinal images can be achieved with the combination of image denoising and sigmoid function. To do so, we introduce the double-pass fundus reflection model in the YPbPr color space and developed a multilevel stimulated denoising strategy termed MUTE. The transmission matrix of the cataract layer is expressed as the superposition of denoised raw images of different levels weighted by pixel-wise sigmoid functions. We further designed an intensity-based cost function that can guide the updating of the model parameters. They are updated by gradient descent with adaptive momentum estimation, which gives us the final refined transmission matrix of the cataract layer. We tested our methods on cataract retinal images from both public and proprietary databases, and we compared the performance of our method with other state-of-the-art enhancement methods. Both visual assessments and objective assessments show the superiority of the proposed method. We further demonstrated three potential applications including blood vessel segmentation, retinal image registrations, and diagnosing with enhanced images that may largely benefit from our proposed methods.

The exploration of the soft X-ray excess in FSRQ 4C+21.35 during the 2014 X-ray flare

ABSTRACT We report the soft X-ray excess feature and an opposite tendency between the optical/UV and X-ray bands during the flare that occurred in 2014 in flat-spectrum radio quasar (FSRQ) 4C+21.35 with the observations by Swift-XRT and Swift-UVOT. These unusual phenomena are rarely reported in FSRQs. The flare was covered from the optical to the X-ray while no prominent activity in the γ-ray was observed, which could be an indication of weaker jet activity during the flare. We carry out the spectral energy distribution ranging from the optical to X-ray based on four models which are the warm corona model (Model-1), the relativistic reflection model (Model-2), the corona with the jet model (Model-3), and the relativistic reflection with the jet model (Model-4). We find some extreme variation of the parameters in Model-2 and Model-4 and they are unable to explain the correlations between the optical/UV and X-ray bands. Model-1 and Model-3 can obtain reasonable parameters and provide an explanation for the observed opposite tendency between the optical/UV and X-ray bands. However, considering the weak jet activity during the X-ray flare, Model-1 is much preferred for describing the soft X-ray excess, hard X-ray emission, as well as the opposite tendency between the optical/UV and X-rays. Based on Model-1, it is suggested that the flare in 2014 is probably due to the variation of the geometry of the corona, which is expected to be more strictly tested with further observations in the future.

GO-DEEP: A Potential Reflection Model for Experiential Learning

Experiential learning is a critical approach in higher education that emphasizes learning by doing, where students engage in activities that promote hands-on learning experiences. Reflection is a crucial component of experiential learning, enabling learners to extract valuable insights and knowledge from their experiences. This study presents our synthesized reflection model, the GO-DEEP reflection model, which includes six main stages to reflect before, during, and after experiences. This study implemented a pre-experimental design to investigate the model’s usefulness and effectiveness in a work-integrated learning course. The course comprised of eight learning sessions with 39 life science students. During each session, the students actively participated in the process of reflection. The students were asked to complete the GO-DEEP level of use questionnaires after sessions four and eight and they submitted their reflection reports after each session through Google Forms. In addition, they responded to the open-ended questions about their perception of the GO-DEEP reflection model and reflection practices. The collected data were analyzed using descriptive, thematic, and t-test analyses. The findings reveal that the university students who used the GO-DEEP reflection model were highly interested in its use and found it beneficial in extracting valuable insights about their learning experiences by constructing knowledge, promoting, and facilitating learning. These outcomes highlight the efficacy and potential of GO-DEEP as a helpful tool in fostering meaningful and impactful educational experiences. Moreover, based on student experience, GO-DEEP has the potential to be applied not only in academic aspects but also in non-academic activities and life experiences.

REFLECTION OF CREATIVITY: THE EXPERIENCE OF STUDYING AND DEVELOPMENT

The article substantiates the relevance of studying and developing the creativity reflection, which determines the perspective of the development of creative potential in the process of ontogenesis and which is the “triggering mechanism” of all self-processes of personality and a condition for successful self-realisation of personality in the future. The authors give a working definition of the “reflection of creativity” concept as a meta-ability to realise creative self-processes of personality: self-exploration, self-reconstruction, self-design and self-creation, awareness of creative achievements and individual characteristics of the “Creative Self”. The authors developed a diagnostic programme and a model of creativity reflection. The ascertaining, transforming and control stages of the study were implemented in a group of younger schoolchildren. Based on the results of the ascertaining experiment, the authors developed a transformative experiment, which is a developmental programme. Based on the empirical research, the authors determine the age specificity and dynamics of development, the correlation structure of significant indicators of creativity reflection, the features of the dynamic and contradictory process of formation of creativity reflection that contribute to the development of younger schoolchildren as subjects of creative activity.

Detection of a strong ~2.5 Hz modulation in the newly discovered millisecond pulsar MAXI J1816–195

ABSTRACT MAXI J1816–195 is a newly discovered accreting millisecond X-ray pulsar that went outburst in 2022 June. Through timing analysis with Neutron star Interior Composition Explorer (NICER) and Nuclear Spectroscopic Telescope Array (NuSTAR) observations, we find a transient modulation at ~2.5 Hz during the decay period of MAXI J1816–195. The modulation is strongly correlated with a spectral hardening, and its fractional rms amplitude increases with energy. These results suggest that the modulation is likely to be produced in an unstable corona. In addition, the presence of the modulation during thermonuclear bursts indicates that it may originate from a disc-corona where the optical depth is likely the main factor affecting the modulation, rather than temperature. Moreover, we find significant reflection features in the spectra observed simultaneously by NICER and NuSTAR, including a relativistically broadened Fe-K line around 6–7 keV, and a Compton hump in the 10–30 keV energy band. The radius of the inner disc is constrained to be Rin = (1.04–1.23) RISCO based on reflection modeling of the broad-band spectra. Assuming that the inner disc is truncated at the magnetosphere radius, we estimate that the magnetic field strength is $\le 4.67 \times 10^{8}\, \rm G$.

Simulating snow-covered forest bidirectional reflectance by extending hybrid geometric optical–radiative transfer model

Accurate simulations of the bidirectional reflectance distribution function (BRDF) of snow-covered forests are crucial for retrieving snow and canopy properties, which affects the analysis of net radiation, radiative forcing, and climate change. The anisotropic reflectance of snow in conifer forests is greatly influenced by the high reflectance of snow and the complex travel pathways of radiation in 3D canopy structures, which complicates BRDF simulations. Although bidirectional reflection models have been widely established for snow-free forests, few studies have attempted to simulate the BRDF in snow-covered forests. Therefore, we propose a new snow-covered forest bidirectional reflectance (SFBR) model by coupling geometric optical and radiative transfer models, which includes a snow anisotropic reflectance model (ART), needle leaf optical properties model (LIBERTY), canopy radiative transfer model (4SAIL), and geometric optical model (GOST2). The SFBR model mainly focuses on conifer forests with snow backgrounds; it can simulate anisotropic reflectance spectra from 400 nm to 2500 nm and is the only model to fully consider discontinuous canopy distribution, topographic effects, and snow anisotropy. The SFBR model was validated by simulating the reflectance over snow-covered forests, the results of which showed good consistency with simulations of 3D scene model and remote sensing observations. The proposed SFBR model has the potential to quantify radiation interactions between the snow background and forest overstory, evaluate the sensitivity of canopy reflectance to snow and forest properties, and retrieve snow-covered forest parameters from satellite-observed reflectance data.

The complex spectral behavior of the newly discovered neutron star X-ray binary Swift J1858.6-0814

ABSTRACT We report on the NuSTAR observation of the newly discovered neutron star X-ray binary Swift J1858.6-0814 taken on 23rd March 2019. The light curve of the source exhibits several large flares during some time intervals of this observation. The source is softer in the high-intensity interval where the large flaring activity mainly occurs. We perform time-resolved spectroscopy on the source by extracting spectra for two different intensity intervals. The source was observed with a 3 − 79keV luminosity of ∼9.68 × 1036 ergs/s and ∼4.78 × 1036 ergs/s for high and low-intensity interval, respectively assuming a distance of 15 kpc. We find a large value of the absorbing column density ($\rm {N_{H}}\sim 1.1\times 10^{23}$ cm−2), and it appears to be uncorrelated with the observed flux of the source. Each spectrum shows evidence of Fe Kα emission in the 5 − 7keV energy band, an absorption edge around ∼7 − 8keV, and a broad Compton hump above 15keV, indicating the presence of a reflection spectrum. The observed features are well explained by the contribution of a relativistic reflection model and a partially covering absorption model. From the best-fit spectral model, we found an inner disc radius to be $4.87_{-0.96}^{+1.63}\,\,R_{ISCO}$ (for the high-intensity interval) and $5.68_{-2.78}^{+9.54}\,\,R_{ISCO}$ (for the low-intensity interval), indicating a significant disc truncation. The disk inclination is found to be relatively low, i < 330. We further place an upper limit on this source’s magnetic field strength considering the disc is truncated at the magnetospheric radius.

A Full-Wave Reference Simulator for Computing Surface Reflectance

Computing light reflection from rough surfaces is an important topic in computer graphics. Reflection models developed based on geometric optics fail to capture wave effects such as diffraction and interference, while existing models based on physical optics approximations give erroneous predictions under many circumstances (e.g. when multiple scattering from the surface cannot be ignored). We present a scalable 3D full-wave simulator for computing reference solutions to surface scattering problems, which can be used to evaluate and guide the development of approximate models for rendering. We investigate the range of validity for some existing wave optics based reflection models; our results confirm these models for low-roughness surfaces but also show that prior rendering methods do not accurately predict the scattering behavior of some types of surfaces. Our simulator is based on the boundary element method (BEM) and accelerated using the adaptive integral method (AIM), and is implemented to execute on modern GPUs. We demonstrate the simulator on domains up to 60 × 60 × 10 wavelengths, involving surface samples with significant height variations. Furthermore, we propose a new system for efficiently computing BRDF values for large numbers of incident and outgoing directions at once, by combining small simulations to characterize larger areas. Our simulator will be released as an open-source toolkit for computing surface scattering.