Target Layouts Research Articles

An Investigation of Multimodal Kinematic Template Matching for Ray Pointing Prediction for Target Selection in VR

We explore the use of multimodal input to predict the landing position of a ray pointer while selecting targets in a virtual reality (VR) environment. We first extend a prior 2D Kinematic Template Matching technique to include head movements. This new technique, Head-Coupled Kinematic Template Matching, was found to improve upon the existing 2D approach, with an angular error of 10.0° when a user was 40% of the way through their movement. We then investigate two additional models that incorporated eye gaze, which were both found to further improve the predicted landing positions. The first model, Gaze-Coupled Kinematic Template Matching resulted in angular error of 6.8° for reciprocal target layouts and 9.1° for random target layouts, when a user was 40% of the way through their movement. The second model, Hybrid Kinematic Template Matching, resulted in angular error of 5.2° for reciprocal target layouts and 7.2° for random target layouts when a user was 40% of the way through their movement. We also found that using just the current gaze location resulted in sufficient predictions in many conditions. We reflect on our results by discussing the broader implications of utilizing multimodal input to inform selection predictions in VR.

Digital inverse patterning solutions for fabrication of high-fidelity microstructures in spatial light modulator (SLM)-based projection lithography.

Digital mask projection lithography (DMPL) technology is gaining significant attention due to its characteristics of free-mask, flexibility, and low cost. However, when dealing with target layouts featuring sizes smaller than the wavelength scale, accurately producing resist patterns that closely match the target layout using conventional methods to design the modulation coefficients of digital masks produced by spatial light modulators (SLM) becomes challenging. Here, we present digital inversion lithography technology (DILT), which offers what we believe to be a novel approach to reverse engineer the modulation coefficients of digital masks. In the case of binary amplitude modulation, DILT achieves a remarkable reduction in pattern errors (PE), reaching the original 0.26. At the same time, in the case of the gray amplitude modulation, the PE can be reduced to the original 0.05, which greatly improves the high-fidelity transfer of the target layout. This significant improvement enhances the accuracy of target design transfer. By leveraging the capabilities of DILT, DMPL can now attain higher precision and reliability, paving the way for more advanced applications in the field of micro-nano device manufacturing.

Hybrid Target Selections by ”Hand Gestures + Facial Expression” for a Rehabilitation Robot

In this study we propose a "hand gesture + face expression" human machine interaction technique, and apply this technique to bedridden rehabilitation robot. "Hand gesture + Facial expression" interactive technology combines the input mode of gesture and facial expression perception. It involves seven basic facial expressions that can be used to determine a target selecting task, while hand gestures are used to control a cursor's location. A controlled experiment was designed and conducted to evaluate the effectiveness of the proposed hybrid technology. A series of target selecting tasks with different target widths and layouts were designed to examine the recognition accuracy of hybrid control gestures. An interactive experiment applied to a rehabilitation robot is designed to verify the feasibility of this interactive technology applied to rehabilitation robots. The experimental results show that the "hand + facial expression" interactive gesture has strong robustness, which can provide a novel guideline for designing applications in VR interfaces, and it can be applied to the rehabilitation robots.

Label-free neural networks-based inverse lithography technology.

Neural network-based inverse lithography technology (NNILT) has been used to improve the computational efficiency of large-scale mask optimization for advanced photolithography. NNILT is now mostly based on labels, and its performance is affected by the quality of labels. It is difficult for NNILT to achieve high performance and extrapolation ability for mask optimization without using labels. Here, we propose a label-free NNILT (LF-NNILT), which is implemented completely without labels and greatly improves the printability of the target layouts and the manufacturability of the synthesized masks compared to the traditional ILT. More importantly, the optimization speed of LF-NNILT is two orders of magnitude faster than the traditional ILT. Furthermore, LF-NNILT is simpler to implement and can achieve better solvers to support the development of advanced lithography.

Preliminary study on spallation target characteristics in an Accelerator-Driven system

This study aims to investigate the neutronic characteristics of spallation targets for Accelerator-Driven subcritical System (ADS) and find the optimal target design for reducing the strength of the required beam current. All the calculations were conducted using the MCNP6.1 with cross-section library ENDF/B-VII. In this study, the influence of several parameters on spallation targets is investigated, such as neutron production with various spallation target layouts, spallation neutron distribution with different proton beam energy levels, and spallation neutron spectrum.

Motion Planning for Convertible Indoor Scene Layout Design

We present a system for designing indoor scenes with convertible furniture layouts. Such layouts are useful for scenarios where an indoor scene has multiple purposes and requires layout conversion, such as merging multiple small furniture objects into a larger one or changing the locus of the furniture. We aim at planning the motion for the convertible layouts of a scene with the most efficient conversion process. To achieve this, our system first establishes object-level correspondences between the layout of a given source and that of a reference to compute a target layout, where the objects are re-arranged in the source layout with respect to the reference layout. After that, our system initializes the movement paths of objects between the source and target layouts based on various mechanical constraints. A joint space-time optimization is then performed to program a control stream of object translations, rotations, and stops, under which the movements of all objects are efficient and the potential object collisions are avoided. We demonstrate the effectiveness of our system through various design examples of multi-purpose, indoor scenes with convertible layouts.

Performance-constrained analogue layout retargeting and optimisation with geometric programming

Layout parasitic has crucial influence on the performance of analogue integrated circuits. The paper presents a performance-constrained analogue layout retargeting and optimisation scheme. Geometric programming (GP), is a kind of nonlinear optimisation problem, is used in the method, which can be transferred or fitted into a convex optimisation problem based on mathematical analyses. Then, a global optimum solution can be achieved. To achieve the desired circuit performance, performance sensitivities based on layout parasitic are carried out in the analogue layout optimisation. In addition, a central difference method is applied to control parasitic-related layout geometries by constructing a set of performance constraints subject to maximum performance deviation. At last, a two-stage Miller-compensated operational amplifier and a single-ended folded cascode operational amplifier are simulated with the proposed scheme. The automatically generated target layouts can satisfy performance constraints to ensure the desired specifications. The experimental results show that the scheme can achieve effective retargeting of analogue circuit with less layout area and better circuit performance.

Assessment of target types and layouts in 3D laser scanning for registration accuracy

3D laser scanning technology is now widely and increasingly used in several construction tasks such as indoor mapping, project control, construction metrology and automation, development of as-built models, and resource management through scanning, data processing, and modeling stages. The accuracy of these stages affects the quality of the end product and can be improved by decreasing the errors caused by manual work processes. This paper focuses specifically on data acquisition errors caused by target setup, acquisition, and reorientation. The paper explores how different target types and target layouts affect registration accuracy. A total of twelve tests were conducted with phase-based and time-of-flight scanners in both exterior and interior scan scenes in order to assess registration errors and time inefficiencies associated with current scanning practices. The paper compares different target types (paper, paddle, and sphere) and presents the lessons learned to achieve optimal target layout design.

Directly performance-constrained template-based layout retargeting and optimization for analog integrated circuits

Due to intrinsic intricacy, layout parasitics exhibit a significant impact on the performance of analog integrated circuits. In this paper a directly performance-constrained parasitic-aware automatic layout retargeting and optimization algorithm is presented. Unlike the conventional sensitivity analysis, a general central-difference based scheme using any simulator for sensitivity computation is deployed. We propose a piecewise sensitivity model to enforce more accurate sensitivity computation during parasitic optimization. Moreover, mixed-integer performance constraints due to parasitics are included in the formulated mixed integer nonlinear programming problem rather than through either indirect parasitic-bound constraints or inaccurate worst-case sensitivities. A graph technique and mixed-integer nonlinear programming are effectively combined to solve the formulated parasitic optimization problem. The automatically generated target layouts can satisfy performance constraints to ensure the desired specifications. The experimental results show that the proposed algorithm can achieve effective retargeting of analog circuits with less layout area and significant reduction in execution time.

Two-mode target selection: Considering target layouts in small touch screen devices

A variety of studies have been conducted to improve methods of selecting a tiny virtual target on small touch screen interfaces of handheld devices such as mobile phones and PDAs. These studies, however, focused on a specific selection method, and did not consider various layouts resulting from different target sizes and densities on the screen. This study proposes a Two-Mode Target Selection (TMTS) method that automatically detects the target layout and changes to an appropriate mode using the concept of an activation area. The usability of TMTS was compared experimentally to those of other methods. TMTS changed to the appropriate mode successfully for a given target layout and showed the shortest task completion time and the fewest touch inputs. TMTS was also rated by the users as the easiest to use and the most preferred. TMTS could significantly increase the ease, accuracy, and efficiency of target selection, and thus enhance user satisfaction when the users select targets on small touch screen devices. Relevance to Industry The results of this study can be used to develop fast and accurate target selection methods in handheld devices with touch screen interfaces especially when the users use their thumb to activate the desired target.

Toward Optimal Target Placement for Neural Prosthetic Devices

Neural prosthetic systems have been designed to estimate continuous reach trajectories (motor prostheses) and to predict discrete reach targets (communication prostheses). In the latter case, reach targets are typically decoded from neural spiking activity during an instructed delay period before the reach begins. Such systems use targets placed in radially symmetric geometries independent of the tuning properties of the neurons available. Here we seek to automate the target placement process and increase decode accuracy in communication prostheses by selecting target locations based on the neural population at hand. Motor prostheses that incorporate intended target information could also benefit from this consideration. We present an optimal target placement algorithm that approximately maximizes decode accuracy with respect to target locations. In simulated neural spiking data fit from two monkeys, the optimal target placement algorithm yielded statistically significant improvements up to 8 and 9% for two and sixteen targets, respectively. For four and eight targets, gains were more modest, as the target layouts found by the algorithm closely resembled the canonical layouts. We trained a monkey in this paradigm and tested the algorithm with experimental neural data to confirm some of the results found in simulation. In all, the algorithm can serve not only to create new target layouts that outperform canonical layouts, but it can also confirm or help select among multiple canonical layouts. The optimal target placement algorithm developed here is the first algorithm of its kind, and it should both improve decode accuracy and help automate target placement for neural prostheses.

Effectiveness of Nuclear Weapons against Buried Biological Agents

This report describes the results of some calculations on the effectiveness of penetrating nuclear weapons of yield 1 and 10 kilotons against targets containing biological agents. The effectiveness depends in detail on the construction of the bunkers, on how the bioagents are stored, on the location of the explosions with respect to the bunkers, the bioagent containers and the surface of the ground, and on the yield of the explosion and the geology of the explosion site. Completeness of sterilization of the bioagents is crucial in determining effectiveness. For most likely cases, however, complete sterilization cannot be guaranteed. Better calculations and experiments on specific target types would improve the accuracy of such predictions for those targets, but significant uncertainties would remain regarding actual geology, actual target layouts, and the position of the explosion with respect to the target. Based on preliminary calculations, casualties from the aboveground effects of underground nuclear explosions would be fewer than the casualties that would result from the dispersal of large quantities of bioagents.