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The origami principle of folding planar sheets into functional three-dimensional devices promises a future with increased compactness and reconfigurability of biomedical robots. To inspire new origami-based biomedical robots, we highlight two categories of origami patterns that are applicable to build compact actuators, deployable stents, and minimally invasive surgery devices. Due to the requirements in system integration, biocompatibility, and payload capability, the conventional paper-based origamis are converted to physical robots by replacing the zero-thickness facets and zero-width folds with thick panels and flexible hinges, respectively. Therefore, the physical origami-based robots become inhomogeneous, making it more complex and challenging to analyze their mechanics. So far, no such model can analyze the mechanics of any physical origami robot. Herein, we propose a computational model that discretizes the continuous structures into truss and spring elements to fulfill this goal. Based on the model, we simulate the identified origami structures under various boundary conditions to investigate their application in biomedical scenarios. This article is expected to accelerate the design iteration of new functional biomedical origami robots.

Periodic Nonuniform Samplings of order N (PNSN) are interleavings of periodic samplings. For a base period T, simple algorithms can be used to reconstruct functions of spectrum included in an union of N intervals δk of length 1/T. In this paper we study the behavior of these algorithms when applied to any function. We prove that they result in N (or less) foldings on , each of δk holding at most one folding.

Folding a thin sheet material such as paper along curves creates a developable surface composed of ruled surface patches. When using such surfaces in design, designers often repeat a process of folding along curves drawn on a sheet and checking the folded shape. Although several methods for constructing such shapes on a computer have been proposed, it is still difficult to check the folded shapes instantly from the crease patterns. In this paper, we propose a simple method that approximately realizes a simulation of curved folds with a triangular mesh from its crease pattern. The proposed method first approximates curves in a crease pattern with polylines and then generates a triangular mesh. In order to construct the discretized developable surface, the edges in the mesh are rearranged so that they align with the estimated rulings. The proposed method is characterized by its simplicity and is implemented on an existing origami simulator that runs in a web browser.

Knowledge-based statistical potentials have been shown to be rather effective in protein 3-dimensional (3D) structure evaluation and prediction. Recently, several statistical potentials have been developed for RNA 3D structure evaluation, while their performances are either still at low level for the test datasets from structure prediction models or dependent on the “black-box” process through neural networks. In this work, we have developed an all-atom distance-dependent statistical potential based on residue separation for RNA 3D structure evaluation, namely rsRNASP, which is composed of short- and long-ranged potentials distinguished by residue separation. The extensive examinations against available RNA test datasets show that, rsRNASP has apparently higher performance than the existing statistical potentials for the realistic test datasets with large RNAs from structure prediction models including the newly released RNA-Puzzles dataset, and is comparable to the existing top statistical potentials for the test datasets with small RNAs or near-native decoys. Additionally, rsRNASP is also superior to RNA3DCNN, a recently developed scoring function through 3D convolutional neural networks. rsRNASP and the relevant databases are available at website https://github.com/Tan-group/rsRNASP.SIGNIFICANCERNAs play crucial roles in catalyzing biochemical reactions and regulating gene expression, and the biological functions of RNAs are generally coupled to their structures. Complementary to experiments, developing computational models to predict RNA 3D structures can be very helpful for understanding RNA biology functions. For a computational model, a reliable energy function is essentially important either for guiding conformational folding or for structure evaluation. For this purpose, we developed a residue-separation-based distance-dependent statistical potential, named rsRNASP which distinguishes the short- and long-ranged interactions, for RNA 3D structure evaluation. Our rsRNASP were examined against extensive test sets and shows overall superior performance over existing top traditional statistical potentials and a recently developed scoring function through 3D convolutional neural networks, especially for realistic test set from various computational structure prediction models.

Aim: The method of utilization of IoT and other evolving techniques in medical equipment design field is discussed in the present paper. A remotely managed interface equipped in a wheelchair cum bed is embedded for elderly or physically challenged people. With the help of a camera embedded in the proposed solution, a real-time remote monitoring of the patient is achieved using an android application on the concerned person. For achieving the above mentioned purpose, the use of linear actuators has been done. This paper further aims to explore the hidden potentials of the merger of all these fields to benefit the end users. Objectives: Remote monitoring of health of the patient through a cloud-based android application. Automatic adjustment of the wheelchair into bed and vice-versa. Automatic stool passing chamber facility is available under the proposed model. Injuries during transportation of the patient from one chair to another (or chair to bed) have been limited in our designed model. Methods: The basic mechanism of proposed wheelchair has been designed using the computer-aided design software. The basic methodology adopted for development of prototype & subsequent “user review analysis” is displayed. The CAD Model of the wheelchair cum stretcher was designed using the “Solid works solid modelling techniques”. The basic structure has been designed with several modifications when compared to the conventional wheelchair design. The computer made design was then utilized for final fabrication of the prototype. The prototype was tested for endurance, load bearing capacity and customer comfort during various phases of development. The feedbacks of several subjects were recorded for future utilization in improved design & fabrication. Results: The proposed model is of utmost importance as the number of critical patients like accident cases, critical pre and post-surgery cases is increasing day by day. Sometimes these patients need intime medication during transition in ambulance while they are picked up from houses and referred to nearby big hospitals. During transition or in hospital, critical patients can be handled efficiently by a specialist doctor through his/her smart phone applications. It also optimizes the services of specialist doctors as we can find the shortage of specialists in Indian hospitals. In a nutshell, this WheelChair system can be moved anywhere due to its portability. Following are the most highlighted features: 1. Authorized relatives and Doctors can see and interact with the patient remotely at any time on his/her smart phone. 2. Authorized relatives and Doctors can see the Vital Sign of patient like BP, ECG, and Pulse etc. at any time through Smart Phone. 3. Doctor can instruct the caretaker to release the emergency drugs through Infusion Pump. 4. Doctor can plan the exceptions, drug infusion, alarm, etc. 5. System is portable and can easily be shifted to ambulance. All transmissions are wireless, so there is no hassle of wires and connectivity. Conclusion: The presented work is limited to the design and fabrication of a new model of wheelchair, which works as a stretcher and has locomotive capabilities. The key feature of the design is its versatility and adaptability to various working conditions. The feedback obtained from various subjects during the testing of wheelchair shows their confidence and a fair degree of comfort which they felt while using the wheelchair. The easy and user-friendly use of the android application helps to monitor the health of the patient. The smartphone camera helped to achieve this data. The analysis of the data can be done in the cloud-based station. The linear actuator has proved to be the low cost and highly reliable equipment to propel the wheelchair.

The design of hybrid nucleic acid nanomaterials capitalizes on the partitioning of architectural and functional roles between structurally diverse RNA modules and chemically robust DNA components. Selecting optimal combinations of RNA and DNA building blocks is the key to preparing stable polygonal RNA-DNA hybrid nanoshapes. Here, we outline a simple screening strategy by gel electrophoresis under native folding conditions to identify combinations of RNA and DNA modules that self-assemble to robust polygonal hybrid nanoshapes. As a proof of concept, we outline the preparation of RNA-DNA hybrid nanoshapes containing a set of different RNA architectural joints, including internal loop motifs and three-way junction (3WJ) folds. For each hybrid nanoshape, we demonstrate the selection process used to identify optimal DNA modules from a library of DNA connectors. The simple screening strategy outlined here provides a general robust method to identify and prepare RNA-DNA hybrid nanoshapes from diverse libraries of discrete nucleic acid building blocks.

We present new algorithms to classify structural ensembles of macromolecules, based on the recently proposed extended similarity measures. Molecular Dynamics provides a wealth of structural information on systems of biologically interest. As computer power increases we capture larger ensembles and larger conformational transitions between states. Typically, structural clustering provides the statistical mechanics treatment of the system to identify relevant biological states. The key advantage of our approach is that the newly introduced extended similiarity indices reduce the computational complexity of assessing the similarity of a set of structures from O(N2) to O(N). Here we take advantage of this favorable cost to develop several highly efficient techniques, including a linear-scaling algorithm to determine the medoid of a set (which we effectively use to select the most representative structure of a cluster). Moreover, we use our extended similarity indices as a linkage criterion in a novel hierarchical agglomerative clustering algorithm. We apply these new metrics to analyze the ensembles of several systems of biological interest such as folding and binding of macromolecules (peptide,protein,DNA -protein). In particular, we design a new workflow that is capable of identifying the most important conformations contributing to the protein folding process. We show excellent performance in the resulting clusters (surpassing traditional linkage criteria), along with faster performance and an efficient cost-function to identify when to merge clusters.

Curved displays have recently become very popular, with wide applications for both industry and consumers. However, built upon initially flat films, most flexible displays are often incompatible with general nondevelopable surfaces. In this paper, we report a method for producing curved displays of nondevelopable shapes by using a structure-mechanics-inspired functional optimization method to design tessellation patterns that fold into the desired shapes. Representative displays in spherical and saddle shapes are demonstrated. The microfabrication process is employed for manufacturing 2D flexible foldable circuit boards, pick-and-place technology is used for placing illuminant elements onto the boards, and mold guidance is used for folding 2-D sheets into curved 3D display prototypes. The proposed technology is feasible for mass production and advances the application of next-generation curved displays.

The aeroelastic model of a folding wing varies with different configurations, so it actually represents a parameter-varying system. Firstly, a new approach based on interpolation of local models is proposed to generate the linear parameter-varying model of a folding wing. This model is capable of predicting the aeroelastic responses during the slow morphing process and is suitable for subsequent control synthesis. The underlying inconsistencies among local linear time-invariant (LTI) models are solved through the modal matching of structural modes and the special treatment of the rational functions in aerodynamic models. Once the local LTI models are represented in a coherent state-space form, the aeroservoelastic (ASE) model at any operating point can be immediately generated by the matrix interpolation technique. Next, based on the present ASE model, the design of a parameterized controller for suppressing the gust-induced vibration is studied. The receptance method is applied to derive fixed point controllers, and the effective independence method is adopted and modified for optimal sensor placement in variable configurations, which can avoid solving ill-conditioned feedback gains. Numerical simulation demonstrates the effectiveness of the proposed interpolation-based modeling approach, and the parameterized controller exhibits a good gust mitigation effect within a wide parameter-varying range. This paper provides an effective and practical solution for modeling and control of the parameterized aeroelastic system.

Motivation In the last decade, de novo protein structure prediction accuracy for individual proteins has improved significantly by utilising deep learning (DL) methods for harvesting the co-evolution information from large multiple sequence alignments (MSAs). The same approach can, in principle, also be used to extract information about evolutionary-based contacts across protein–protein interfaces. However, most earlier studies have not used the latest DL methods for inter-chain contact distance prediction. This article introduces a fold-and-dock method based on predicted residue-residue distances with trRosetta. Results The method can simultaneously predict the tertiary and quaternary structure of a protein pair, even when the structures of the monomers are not known. The straightforward application of this method to a standard dataset for protein–protein docking yielded limited success. However, using alternative methods for generating MSAs allowed us to dock accurately significantly more proteins. We also introduced a novel scoring function, PconsDock, that accurately separates 98% of correctly and incorrectly folded and docked proteins. The average performance of the method is comparable to the use of traditional, template-based or ab initio shape-complementarity-only docking methods. Moreover, the results of conventional and fold-and-dock approaches are complementary, and thus a combined docking pipeline could increase overall docking success significantly. This methodology contributed to the best model for one of the CASP14 oligomeric targets, H1065. Availability and implementation All scripts for predictions and analysis are available from https://github.com/ElofssonLab/bioinfo-toolbox/ and https://gitlab.com/ElofssonLab/benchmark5/. All models joined alignments, and evaluation results are available from the following figshare repository https://doi.org/10.6084/m9.figshare.14654886.v2. Supplementary information Supplementary data are available at Bioinformatics online.

Most shipyard companies maintain efficiency in all aspects of their business to survive. One of these aspects is ship production costs and their reduction. This study proposes a solution to this problem using an optimization method. A hatch cover composed of plates and stiffeners was selected as a case study. In this study, the mass and material cost of the hatch cover was optimized as an objective function using the Pareto approach with developed optimization methods. Plate thickness t, stiffener shape s, and plate material type m were selected as the design variables in this study along with some constraints. To estimate the optimal plate thickness, an expression of stress equations was developed using an optimization technique. Furthermore, stiffener shape and plate material type selection were optimized using a genetic algorithm (GA). The results show that the optimization method is effective to decrease the mass and material cost of a hatch cover.

Origami, the ancient art of paper folding, has shown its potential as a versatile platform to design various reconfigurable structures. The designs of most origami-inspired architected materials rely on a periodic arrangement of identical unit cells repeated throughout the whole system. It is challenging to alter the arrangement once the design is fixed, which may limit the reconfigurable nature of origami-based structures. Inspired by phase transformations in natural materials, here we study origami tessellations that can transform between homogeneous configurations and highly heterogeneous configurations composed of different phases of origami unit cells. We find that extremely localized and reprogrammable heterogeneity can be achieved in our origami tessellation, which enables the control of mechanical stiffness and in-situ tunable locking behavior. To analyze this high reconfigurability and variable stiffness systematically, we employ Shannon information entropy. Our design and analysis strategy can pave the way for designing new types of transformable mechanical devices. Origami-inspired metamaterials are attractive for their programmable shape-shifting properties but are typically characterized by low structural rigidity. Here, 3D heterogeneous origami structures display highly reconfigurable mechanical properties, including finely controllable and reversible stiffness variation.

In recent years, as a result of advancing VLSI technology, Orthogonal Frequency Division Multiplexing (OFDM) has received a great deal of attention and has been adopted in many new generation wideband data communication systems such as IEEE 802.11a, IEEE 802.16e, HiPerLAN/2, Digital Audio/Video Broadcasting (DAB/DVB), and for 4G Radio mobile communications. This is because of its high bandwidth efficiency as the use of orthogonal waveforms with overlapping spectra. The immunity to multipath fading channel and the capability for parallel signal processing make it a promising candidate for the next generation mobile communication systems. The modulation and demodulation of OFDM based communication systems can be efficiently implemented with an FFT and IFFT, which has made the FFT valuable for those communication systems. The complexity of an OFDM system highly depends upon the computation of Fast Fourier Transform (FFT) algorithm. With the advent of new technology in the fields of VLSI and communication, there is also an ever growing demand for high speed processing and low area design. It is also a well-known fact that the multiplier unit forms an integral part of processor design. Due to this regard, high speed multiplier architectures become the need of the day.

Deacon speculates on the origin of interpretation of signs using autocatalytic origin of life models and Peircean terminology. I explain why interpretation evolved only later as a triadic intervention between symbols and actions. In all organisms the passive one-dimensional genetic informational symbol sequences are converted to active functional proteins or nucleic acids by three-dimensional folding. This symbol grounding is a direct symbol-to-action conversion. It is universal throughout all evolution. Folding is entirely a lawful physical process, leaving neither freedom nor necessity for interpretation. Similarly, the initial converse action-to-symbol conversion of sensory inputs also leaves no freedom for interpretation until after the action-to-symbol conversion.

3D shape completion from single-view scan is an important task for follow-up applications such as recognition and segmentation, but it is challenging due to the critical sparsity and structural incompleteness of single-view point clouds. In this paper, a three-stage generative network (TSGN) is proposed for single-view point cloud completion, which generates fine-grained dense point clouds step by step and effectively overcomes the ubiquitous problem—the imbalance between general and individual characteristics. In the first stage, an encoder–decoder network consumes a partial point cloud and generates a rough sparse point cloud inferring the complete geometric shape. Then, a bi-channel residual network is designed to refine the preliminary result with assistance of the original partial input. A local-based folding network is introduced in the last stage to extract local context information from the revised result and build a dense point cloud with finer-grained details. Experiments on ShapeNet dataset and KITTI dataset validate the effectiveness of TSGN. The results on ShapeNet demonstrate the competitive performance on both CD and EMD.

Strategies for investigating and optimizing the expression and folding of proteins for biotechnological and pharmaceutical purposes are in high demand. Here, we describe a dual-reporter biosensor system that simultaneously assesses in vivo protein translation and protein folding, thereby enabling rapid screening of mutant libraries. We have validated the dual-reporter system on five different proteins and find an excellent correlation between reporter signals and the levels of protein expression and solubility of the proteins. We further demonstrate the applicability of the dual-reporter system as a screening assay for deep mutational scanning experiments. The system enables high throughput selection of protein variants with high expression levels and altered protein stability. Next generation sequencing analysis of the resulting libraries of protein variants show a good correlation between computationally predicted and experimentally determined protein stabilities. We furthermore show that the mutational experimental data obtained using this system may be useful for protein structure calculations., Heterologous expression of recombinant proteins often results in misfolding, aggregation and degradation. Here, we show an in vivo dual-biosensor system that simultaneously assesses protein translation and protein folding, thereby enabling rapid screening of expression strains as well as mutant libraries.

Origami that can form various shapes by setting simple creases on the paper and folding along these creases has a lot of applications from the fields of art to engineering. The inverse problem of origami that determines the distribution of creases based on the desired shape is very complicated. In this paper, we use theoretical kinematics to systematically analyse an inverse folding problem of a toy about how to fold a piece of paper into a disc through a smaller hole without breaking it. The results show that some four-crease and six-crease patterns can achieve the expected function, and they can be easily folded with 1 degree of freedom (DOF). It not only opens up a new way to solve the inverse folding problem but also helps students to understand mechanisms and machine theory.

Flexible light-emitting devices that can transform from two-dimensional to three-dimensional (3D) forms could be of use in the development of next-generation displays. Various approaches for converting two-dimensional structures into 3D architectures have been explored, including origami methods that rely on folding along lines in which a structure has been thinned. But the fabrication of foldable 3D light-emitting devices remains challenging due, in particular, to the lack of a practical method for patterning the folding lines. Here we show that 3D foldable quantum dot light-emitting diodes (QLEDs) can be created using laser patterning and metal etch-stop layers with customized ablation thresholds. The approach allows etching to be limited to selected layers of the multilayered QLEDs, and it can be precisely tuned by using alloy-type etch-stop layers. The approach can be used to create QLED architectures with extremely small bending radii (0.047 mm), and we illustrate its capabilities by fabricating a 3D foldable passive matrix array of QLEDs that can display letters and numbers. Two-dimensional arrays of quantum dot light-emitting diodes can be folded into three-dimensional architectures—including a passive matrix array that can display letters and numbers—by using laser patterning and metal etch-stop layers to create folding lines.

Students’ previous knowledge at a superficial level is reviewed when they solve mathematical problems. This action is imperative to strengthen their knowledge and provide the right information needed to solve the problems. Furthermore, Pirie and Kieren's theory stated that the act of returning to a previous level of understanding is called folding back. Therefore, this descriptive-explorative study examines high school students' levels of knowledge in solving mathematics problems using the folding back method. The sample consists of 33 students classified into male and female groups, each interviewed to determine the results of solving arithmetic problems based on gender. The results showed differences in the level of students' understanding in solving problems. Male students carried out the folding back process at the level of image having, formalizing, and structuring. Their female counterparts conducted it at image-making, property noticing, formalizing, and observing. Subsequently, both participants were able to carry out understanding activities, including explaining information from a mathematical problem, defining the concept, having an overview of a particular topic, identifying similarities and differences, abstracting mathematical concepts, and understanding its ideas in accordance with a given problem. This study suggested that Pirie and Kieren's theory can help teachers detect the features of students’ understanding in solving mathematical problems.

We take an institutional perspective to examine how innovation thrives under conditions of resistance. Specifically, we conceive illicit innovation as a process of successive institutionalization of a new practice in the face of contrary law. In the German federal state of Bavaria, the global movement of craft-beer brewing collides with a regional jurisdiction that prohibits precisely these brewing practices and instead protects the traditional institution of purity-brewing (Reinheitsgebot). Grounded on an embedded qualitative case study of brewers and industry representatives, we build a theory of institutional folding of new norms and practices over established ones. This way, creative brewers have succeeded in legitimizing new practices of naturalness-brewing (Natürlichkeitsgebot). Whereas the legal resistance has stimulated brewers to create an original counter-institution, the illicit innovation has also begun to change the institutional context of the beer industry in Bavaria.

Origami enables the folding of objects into a variety of shapes. This paper presents a swimming robot using the folding and unfolding motion of a tabular origami. A squid‐inspired jet propulsion mechanism is used to design an origami swimming robot. The swimming robot utilizes a pulsed‐jet mechanism through the folding motion of the tubular origami structure, which could deform and undulate to provide propulsion for the swimming robot. The robot is incorporated in a stable body, while both swimming forward and steering are generated by the folding motion of the origami structure and undulating fins. An analytical model to investigate the jet propulsion mechanism to capture the relationship between the motor's speed and the generated thrust is developed. The prototype of the swimming robot is fabricated by 3D printing, and experiments verify the robot's components and assembly system. The results show that the swimming robot could achieve swimming forward by folding origami, which could provide unique advantages over other existing underwater propulsion technologies, including scalability and water treatment capabilities. The origami structure provides a novel and simple propulsion mechanism for the swimming robot here, and the mechanism promotes the development of a new class of independent swimming robots.

Motivation The development of an open-source platform to predict protein 1D features and 3D structure is an important task. In this paper, we report an open-source toolkit for protein 3D structure modeling, named OPUS-X. It contains three modules: OPUS-TASS2, which predicts protein torsion angles, secondary structure and solvent accessibility; OPUS-Contact, which measures the distance and orientation information between different residue pairs; and OPUS-Fold2, which uses the constraints derived from the first two modules to guide folding. Results OPUS-TASS2 is an upgraded version of our previous method OPUS-TASS. OPUS-TASS2 integrates protein global structure information and significantly outperforms OPUS-TASS. OPUS-Contact combines multiple raw co-evolutionary features with protein 1D features predicted by OPUS-TASS2, and delivers better results than the open-source state-of-the-art method trRosetta. OPUS-Fold2 is a complementary version of our previous method OPUS-Fold. OPUS-Fold2 is a gradient-based protein folding framework based on the differentiable energy terms in opposed to OPUS-Fold that is a sampling-based method used to deal with the non-differentiable terms. OPUS-Fold2 exhibits comparable performance to the Rosetta folding protocol in trRosetta when using identical inputs. OPUS-Fold2 is written in Python and TensorFlow2.4, which is user-friendly to any source-code-level modification. Availabilityand implementation The code and pre-trained models of OPUS-X can be downloaded from https://github.com/OPUS-MaLab/opus_x. Supplementary information Supplementary data are available at Bioinformatics online.

International audience; The development of ultrafast kinetic methods is one of the factors that allowed the research on protein folding to flourish over the last twenty years. The introduction of new optical triggering techniques enabled to experimentally investigate the protein dynamics at the nanosecond to millisecond timescale, allowing researchers to test theoretical predictions and providing experimental benchmarks for computer simulations. In this work the details of how to perform kinetic experiments by the laserinduced temperature jump technique, using the two most commonly used probing techniques (namely infrared absorption and fluorescence spectroscopy) are given, with a strong emphasis on the practical details.

We present the E2EDNA simulation protocol and accompanying code for the molecular biophysics and materials science communities. This protocol is both easy to use and sufficiently efficient to simulate single-stranded (ss)DNA and small analyte systems that are central to cellular processes and to nanotechnologies such as DNA aptamer-based sensors. Existing computational tools used for aptamer design focus on cost-effective secondary structure prediction and motif analysis in the large datasets produced by SELEX experiments. As a rule, they do not offer flexibility with respect to the choice of the theoretical engine or a direct access to the simulation. Practical aptamer optimization often requires higher accuracy predictions for only a small subset of sequences suggested e.g., by SELEX experiments, but in the absence of a streamlined procedure this task is extremely time and expertise intensive. We address this gap by introducing E2EDNA, a computational framework powered by Tinker, POLTYPE, MacroMoleculeBuilder and NUPACK that accepts a DNA sequence in the FASTA format and the chemical structures of the desired ligands in the sdf format as inputs and performs approximate folding followed by a refining step, docking, and molecular dynamics sampling at the desired level of accuracy. As a case study we simulate a DNA-UTP (Uridine TriPhosphate) complex in water using the state-of-the-art AMOEBA polarizable force field, beginning with identifying a representative 3D structure of the aptamer at experimental conditions, and then assessing the binding affinity of UTP.

Sparse code multiple access (SCMA) is a promising technology for the development of wireless communication, which supports a large number of overloading users and enjoys high spectral efficiency. However, conventional SCMA decoders suffer very high complexity in implementations. Changing the updating scheme is a superior approach to reduce complexity, which guarantees the updated information immediately join in the following message propagating of the current iteration and accelerates the decoding convergence. In this paper, a row-layered message passing algorithm (MPA) is proposed, which offers a good trade-off between the hardware complexity and the bit error rate (BER) performance. Simulation results show that the proposed decoder saves 66.7% computation complexity compared with the original MPA with the similar BER performance. Pipelining and folding technology are adopted in VLSI implementations. The synthesis results with 45-nm CMOS technology show that the proposed decoder can achieve higher hardware efficiency and throughput under a high frequency than the existing decoders, achieving 1777.78 Mb/s throughput with 1.112 mm2 area consumption.

This brief proposes a novel generalized Fractional Folding (FF) architecture for digital signal processing integrated circuits. With this new structure, a Fractional Folding based enhanced Parallel Inversionless Berlekamp-Massey (FF-ePIBM) Reed-Solomon Decoder is presented of which the number of processing element (PE) can be reduced to only one, resulting in ultra-low hardware complexity. The FF-ePIBM VLSI architecture can greatly reduce the hardware cost by about 60% compare to the fully expanded parallel ePIBM architecture. With FF-ePIBM architecture, syndrome calculation (SC) block and Chien search & error evaluation (CSEE) block are able to operate at a lower frequency resulting in about 14.8% power saving. A polyphase clock signal is needed in order to achieve fractional folding function according to specific fractional-factor. It is generated from Delay Locked Loop (DLL) at little or no extra cost in different SoCs. To maximize the throughput of decoder, pipelined architecture is adopted to optimize critical path delay. The RS (255, 239) decoder with FF-ePIBM architecture is finally implemented with 40nm CMOS technology. The synthesized results demonstrate that the decoder has a gate count of 12.9k and can operate at 3.1GHz to achieve a highest throughput of 24.8Gb/s and a best TSNT FoM value of 592 to this date.

The rear-view mirror is one of the main devices found in cars. A mirror is a mirror used to see the traffic of a vehicle behind when it is about to veer, stop or change lanes. The purpose of this study was to design a pre-crash performance test of the rearview mirror. That is a system that will automatically perform mirror folding automatically based on the distance of the object in front of it. The system will reduce the risk of broken or scratched due to driver negligence. The research method at a time when the barrier is 30cm (±20cm) away from the front or back of the rearview mirror will read that distance which will then transmit to the Arduino. Arduino will process the data and send data for the speed reduction process by warning that there is an object in front or behind the rearview mirror and when the distance is

During the cold season, the cold protective products are often short during evacuation life after a natural disaster. If evacuees can make and wear simple cold protective gears by using materials obtainable on site, it will reduce the burden on the evacuees in emergent situation. Therefore, we investigated the structure constructed by folding newsprint paper, which can improve the heat retention effect and be applied to various body shapes. Focusing on the glide reflection structure repeating a smaller chamber, the basic size was determined by experiments with reference to the accordion shape, and the experimental results indicated that the heat retention effect was significantly greater than that of a mere air layer and those of ordinary fabrics. Next, it was found that the apex angle of structure had no significant difference in the heat retention effect. Then, the dimensions of the structure were determined to maintain the air layer under the pressure of the clothes by simulation of structural analyses. Finally, we made a temporary cold protective gear that can practically cover the trunk of the body and found that the heat retention effect was significantly higher than that of unprocessed newsprint and that of accordion shape.

RNA cotranscriptional folding is the phenomenon in which an RNA transcript folds upon itself while being synthesized out of a gene. The oritatami system is a computation model of this phenomenon, which lets its sequence (transcript) of beads (abstract molecules) fold cotranscriptionally by the interactions between beads according to the binding ruleset. In such models based on self-assembly, one of the key questions is the ability to construct fractal structures. We focus on the problem of generating an infinite fractal curves using a cyclic oritatami system, which has an infinite periodic transcript. We first establish a formal definition of drawing a curve using an oritatami system, proposing conditions and restrictions with reference to prior oritatami designs for possibly infinite conformations. Under such definition, we prove that it is impossible to draw a Koch curve or a Minkowski curve infinitely. We then establish sufficient conditions of infinite aperiodic curves that a cyclic oritatami system cannot fold.

Sheet springback and structural deformation of the folding mechanism are key issues in the sheet metal–forming process. Elastic-plastic bending theory and numerical simulation are applied to study the forming performance of sheet metal. First, a springback prediction model under general assumptions is established, based on the constitutive relationship of the elastic-plastic linear hardening material. In addition, the influences of processing parameters, such as sheet thickness and forming angle on springback, are analysed according to the theoretical model and verified by experiments. Then, a laser tracker is used to acquire the folding trajectory, and the structural deformation of the folding mechanism is confirmed by trajectory comparison. On this basis, numerical simulations are performed to collect deformation parameters, and a formula for mechanical compensation is obtained by linear fitting to the simulation data. Finally, experimental tests are carried out to verify the accuracy of the compensation model. The results show that the forming precision of the sheet metal can be controlled in the range of $\pm 10^{\prime }$ . The proposed method is generally applicable to linear hardening materials and operation conditions where the sheet thickness ranges from 0.8 to 3 mm.

She and she worship are very old traditions in Chinese society, originating from the ancient time and lasting until today. Both existed in the rites of the state and play important roles in popular...

Soft pneumatic actuators (SPAs) based on inherently compliant materials have been developed by integrating with a fabric, a fiber reinforcement, or applying origami patterns. However, the fabric and fiber-reinforced SPAs are limited by the relatively large volumes of air needed to achieve the desired motions, and conventional ‘origami-structured’ SPAs based on simple paper folding may not be durable and provide limited force. In this letter, an origami-structured actuating module fabricated by embedding a rigid origami structure in a fabric, which is applicable to any origami patterns including Yoshimura, Waterbomb, and so on, was proposed to improve durability and supporting force. Specially, the Yoshimura pattern-based origami-structured actuating module was analytically modeled to determine the design parameters of the actuating module so that it can provide enough supporting force and range of motion of the upper limb. A wearable system with the optimized origami-structured actuating module, which is durable, adaptable, and capable of supporting the upper limb motion, was developed to assist the upper limb without interfering natural movements.

The nrotectonic structure of the Kerch-Taman folded zone, the southern deformed part of the Azov-Kuban piedmont trough, has a number of structural features and a history of deformation development. The authors divide the zone into five transverse segments, differing in the age of the main phase of folding. In the central Taman segment, folding is still going on, while in the framing segments, the main phases of folding took place in the Pliocene. In the peripheral segments, the main phase of folding is older - Early-Middle Miocene. The boundaries of the Kerch-Taman zone, as well as its youngest, the Taman segment, coincide with the transverse fault (fault-flexure) zones. It is shown that the southern frame of the Kerch-Taman folded zone is the continuation of the structures of the Crimean Mountains and the Northwestern Caucasus. The correlation of mud volcanism manifestations with tectonic elements of the Taman segment is noted to be ambiguous.

The folding wing, as a possible concept for designing morphing aircraft, has gained special attention. However, such a wing may encounter complex nonlinear aeroelastic effects with bilinear-hinge stiffnesses during the in-flight morphing process. This paper presents a novel parameterized nonlinear aeroelastic modeling methodology, based on the substructure synthesis of the folding wing with fictitious mass in hinge joints and piecewise-linear theory. The most attractive feature of the present methodology is that the nonlinear aeroelastic dynamics of the wing can be efficiently represented by piecewise, parameterized, linear subsystems using the parameterized fictitious mode method. To demonstrate the accuracy of the present method in representing the nonlinear dynamics of the morphing wing, a folding wing with bilinear stiffness in both fuselage-inboard and inboard-outboard hinges was selected as a numerical example. The numerical results demonstrate that the natural modes of each linear subsystem, as well as the limit-cycle oscillations of the folding wing at different folding angles, can be accurately predicted. In addition, a comparison between the time cost of the present parameterized method and the direct nonparameterized method was made. The comparison showed that the parameterized, nonlinear, aeroelastic modeling methodology provides an efficient way to analyze the nonlinear aeroelastic responses of a morphing wing with bilinear-hinge stiffness.

Based on the suspension of a missile using folding rotary wings and airbags, in order to improve the basic parameters and motion characteristics of the rotor during the unfolding process and analyze the aerodynamic characteristics of the entire device in the suspension state, after proposing a scheme of double-spin mechanism, the main folding and unfolding mechanism, initial driving device, rotating driving device, and locking mechanism were designed, and the simulation research is studied by the Automatic Dynamic Analysis of Mechanical System and Ansys Fluent Fluid Simulation software, respectively. The results show that the rotation rate was controlled at 41.8 mm/s, the various motion parameters are reasonable, and the operation process is relatively smooth, with high reliability. The speed and pressure value at the tip of the rotor are higher and the aerodynamic disturbance is obvious, which has a great influence on the aerodynamic performance. The speed and pressure distribution of the surrounding flow field is stable, the lift provided is 46 N, and the lift coefficient is 0.55, which can ensure the long-time suspension state of the missile. This paper puts forward a valuable design idea and has practical reference value for the research of the suspended missile.

In a seminal paper, Stallings introduced folding of morphisms of graphs. One consequence of folding is the representation of finitely-generated subgroups of a finite-rank free group as immersions of finite graphs. Stallings's methods allow one to construct this representation algorithmically, giving effective, algorithmic answers and proofs to classical questions about subgroups of free groups. Recently Dani--Levcovitz used Stallings-like methods to study subgroups of right-angled Coxeter groups, which act geometrically on CAT(0) cube complexes. In this paper we extend their techniques to fundamental groups of non-positively curved cube complexes., 12 pages

This study proposes an oblique folding mechanism design inspired by the wings of Borneo camphor seeds to enable the blades of wind turbines to pitch and cone. The blade pitching increases the power...

In this paper, a feedback control law is proposed to solve the asymptotic tracking problem for a ball bouncing in a triangular billiard. This controller is designed by firstly transforming the billiard table into a surface on which the ball moves without experiencing any impact, i.e. by reflecting the billiard table rather than the ball trajectory and designing a position feedback controller based on such an unfolded billiard table. Furthermore, it is shown how such an infinite-billiard table can be mapped to the surface of a torus, thus leading to bounded trajectories of the ball.

In this paper, numerical simulation and laboratory experiments were combined to research the tucked-in behavior of the yarn in the pneumatic tucked-in selvedge apparatus, and explore the effect of initial pressure of oblique-blowing airflow and folding-in airflow on yarn tucked-in. This work focused on the motion of a single yarn of which one end was fixed while the other was free. Initial pressures for oblique-blowing airflow and folding-in airflow were set as parameters. A numerical model was developed to simulate the process based on the one-way fluid–structure interaction. Then a laboratory experiment was carried out with the help of a high-speed camera to record the motion behaviors of yarns. The motions were compared with the simulation data and showed that the proposed numerical model can properly replicate the motion of yarn and its points in the airflow field. Each group of yarns with different initial pressures was able to be tucked-in and had an elongation. Increasing the initial pressures of oblique-blowing airflow from 0.3 MPa to 0.4 MPa and folding-in airflow from 0.35 MPa to 0.4MPa shortened the time for the yarn to complete the entire oblique-blowing and tucked-in process by 0.4625 ms, and extended the yarn elongation by 0.151 mm.

RNA origami is a framework for the modular design of nanoscaffolds that can be folded from a single strand of RNA and used to organize molecular components with nanoscale precision. The design of genetically expressible RNA origami, which must fold cotranscriptionally, requires modelling and design tools that simultaneously consider thermodynamics, the folding pathway, sequence constraints and pseudoknot optimization. Here, we describe RNA Origami Automated Design software (ROAD), which builds origami models from a library of structural modules, identifies potential folding barriers and designs optimized sequences. Using ROAD, we extend the scale and functional diversity of RNA scaffolds, creating 32 designs of up to 2,360 nucleotides, five that scaffold two proteins, and seven that scaffold two small molecules at precise distances. Micrographic and chromatographic comparisons of optimized and non-optimized structures validate that our principles for strand routing and sequence design substantially improve yield. By providing efficient design of RNA origami, ROAD may simplify the construction of custom RNA scaffolds for nanomedicine and synthetic biology.

Miura-ori is a rigid origami structure utilized in the packaging of deployable solar panels for use in space or in the folding of maps. It's pattern can largely reduce the membrane stress and improve the work efficiency. Inspired by origami structures, we numerically and experimentally studied a scalable solar sail structure. As an improvement of the existing membrane simulations, a variable Poisson's ratio model considering the wrinkling effect of the membrane was introduced. We focused on a quadrant shape and studied how its geometry parameters and initial imperfections affect the membrane mechanical behavior. We also designed and fabricated a pantographic mechanism as an origami membrane actuator. In addition, design protocols of deployment applied to a scalable gossamer structure were proposed.