Fast convergence to equilibrium for long-chain polymer melts using a MD/continuum hybrid method

Effective and fast convergence toward an equilibrium state for long-chain polymer melts is realized by a hybrid method coupling molecular dynamics and the elastic continuum. The required simulation time to achieve the equilibrium state is reduced drastically compared with conventional equilibration methods. The polymers move on a wide range of the energy landscape due to large-scale fluctuation generated by the elastic continuum. A variety of chain structures is generated in the polymer melt which results in the fast convergence to the equilibrium state.Comment: 13 page

Task support system by displaying instructional video onto AR workspace

This paper presents an instructional support system based on aug-mented reality (AR). This system helps a user to work intuitively by overlaying visual information in the same way of a navigation system. In usual AR systems, the contents to be overlaid onto real space are created with 3D Computer Graphics. In most cases, such contents are newly created according to applications. However, there are many 2D videos that show how to take apart or build elec-tric appliances and PCs, how to cook, etc. Therefore, our system employs such existing 2D videos as instructional videos. By trans-forming an instructional video to display, according to the user’s view, and by overlaying the video onto the user’s view space, the proposed system intuitively provides the user with visual guidance. In order to avoid the problem that the display of the instructional video and the user’s view may be visually confused, we add var-ious visual effects to the instructional video, such as transparency and enhancement of contours. By dividing the instructional video into sections according to the operations to be carried out in order to complete a certain task, we ensure that the user can interactively move to the next step in the instructional video after a certain op-eration is completed. Therefore, the user can carry on with the task at his/her own pace. In the usability test, users evaluated the use of the instructional video in our system through two tasks: a task involving building blocks and an origami task. As a result, we found that a user’s visibility improves when the instructional video is transformed to display according to his/her view. Further, for the evaluation of visual effects, we can classify these effects according to the task and obtain the guideline for the use of our system as an instructional support system for performing various other tasks

Sequential Fuzzy Cluster Extraction and Its Robustness Against Noise

Partitional clustering methods such as C-Means classify all samples into clusters. Even a noise sample that is distant from any cluster is assigned to one of the clusters. Noise samples included in clusters bias the clustering result and tend to produce meaningless clusters. Our clustering method repeats to extract mutually close samples as a cluster and leave isolated noises unclustered. Thus, the produced clusters are less affected by noises than those of C-Means. Because clusters can be obtained analytically by our method, repeated trials to avoid local minima are not necessary. The method is shown to be effective for extracting straight lines from images in the experiments. Keywords: Cluster Extraction, Clustering, Eigenvalue Problem, Scale, Noise 1 Introduction The purpose of clustering is to find clusters from a set of samples, where a cluster is comprised of a number of similar samples grouped together[1]. In general settings, a sample i(i = 1; 1 1 1 ; n) is represented by a s..

Supramolecular Porphyrin‐Based Metal–Organic Frameworks with Fullerenes: Crystal Structures and Preferential Intercalation of C70

The syntheses and characterization of two new porphyrin‐based metal–organic frameworks (P‐MOFs), through the complexation of 5,10,15,20‐tetra‐4‐pyridyl‐21 H,23 H‐porphine (H2TPyP) and copper(II) acetate (CuAcO) in the presence of the fullerenes C60 or C70 are reported. Complex 1 was synthesized in conjunction with C60, and this reaction produced a two‐dimensional (2D) porous structure with the composition CuAcO‐CuTPyP⊃m‐dichlorobenzene (m‐DCB), in which C60 molecules were not intercalated. Complex 2 was synthesized in the presence of C70, generating a three‐dimensional (3D) porous structure, in which C70 was intercalated, with the composition CuAcO‐CuTPyP⋅C70⊃m‐DCB⋅CHCl3. The structures of these materials were determined by X‐ray diffraction to identify the supramolecular interactions that lead to 2D and 3D crystal packing motifs. When a combination of C60 and C70 was employed, C70 was found to be preferentially intercalated between the porphyrins.How Porefessional: Solutions of copper(II) acetate (CuAcO), 5,10,15,20‐tetra‐4‐pyridyl‐21 H,23H‐porphine (H2TPyP), and fullerenes C70 or C60 produce crystalline precipitates with the compositions CuAcO‐CuTPyP⊃m‐dichlorobenzene (m‐DCB) (1) and CuAcO‐CuTPyP⋅C70⊃m‐DCB⋅CHCl3 (2). The structures of these materials have been determined by X‐ray diffraction to identify the supramolecular interactions that lead to two‐ and three‐dimensional crystal packing motifs. Complexation in the presence of both C60 and C70 leads to preferential intercalation of C70 between the porphyrins.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137276/1/asia201501422-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137276/2/asia201501422.pd

Supramolecular Porphyrin‐Based Metal–Organic Frameworks with Fullerenes: Crystal Structures and Preferential Intercalation of C70

The syntheses and characterization of two new porphyrin‐based metal–organic frameworks (P‐MOFs), through the complexation of 5,10,15,20‐tetra‐4‐pyridyl‐21 H,23 H‐porphine (H2TPyP) and copper(II) acetate (CuAcO) in the presence of the fullerenes C60 or C70 are reported. Complex 1 was synthesized in conjunction with C60, and this reaction produced a two‐dimensional (2D) porous structure with the composition CuAcO‐CuTPyP⊃m‐dichlorobenzene (m‐DCB), in which C60 molecules were not intercalated. Complex 2 was synthesized in the presence of C70, generating a three‐dimensional (3D) porous structure, in which C70 was intercalated, with the composition CuAcO‐CuTPyP⋅C70⊃m‐DCB⋅CHCl3. The structures of these materials were determined by X‐ray diffraction to identify the supramolecular interactions that lead to 2D and 3D crystal packing motifs. When a combination of C60 and C70 was employed, C70 was found to be preferentially intercalated between the porphyrins.How Porefessional: Solutions of copper(II) acetate (CuAcO), 5,10,15,20‐tetra‐4‐pyridyl‐21 H,23H‐porphine (H2TPyP), and fullerenes C70 or C60 produce crystalline precipitates with the compositions CuAcO‐CuTPyP⊃m‐dichlorobenzene (m‐DCB) (1) and CuAcO‐CuTPyP⋅C70⊃m‐DCB⋅CHCl3 (2). The structures of these materials have been determined by X‐ray diffraction to identify the supramolecular interactions that lead to two‐ and three‐dimensional crystal packing motifs. Complexation in the presence of both C60 and C70 leads to preferential intercalation of C70 between the porphyrins.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137276/1/asia201501422-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137276/2/asia201501422.pd

Structure of liquid Sn over a wide temperature range from neutron scattering experiments and first-principles molecular dynamics simulation : A comparison to liquid Pb

The structure of liquid Sn was studied by neutron scattering experiments in the widest temperature range that was ever performed. Though, on increasing temperature, the existence of the shoulder in the structure factor, S(Q), becomes less clear in the change of the overall shape of the S(Q), the structure related to this shoulder seems to be present even at 1873 K. The first-principle molecular-dynamics ~FPMD! simulation was performed for the first time for liquid Sn by using the cell size of 64 particles. The calculated results well reproduced S(Q) obtained by the neutron experiments. The angle distribution, g(3)(u ,rc), was evaluated for the angle between vectors from centered atom to other two atoms in spheres of cutoff radii rc's. The g(3)(u ,rc) shows that, with the decrease of rc from 0.4 to 0.3 nm, a rather sharp peak around 60 ° disappears and only a broad peak around 100 ° remains; the former peak may be derived from the feature of the closely packed structures and the latter one is close to the tetrahedral angle of 109 °. In addition, the coordination number, n, of liquid Sn counted within the sphere of rc=0.3 nm is found to be 2–3 and does not change with the increase of temperature even up to 1873 K. These facts indicate that at least the fragment of the tetrahedral unit may be essentially kept even at 1873 K for liquid Sn. For comparison, the FPMD simulation was performed for the first time also for liquid Pb. No sign of the existence of the tetrahedral structure was observed for liquid Pb. Unfortunately, the self-diffusion coefficients, D's, obtained from this FPMD for liquid Sn do not agree with those obtained by the microgravity experiments though the structure factors, S(Q)'s, are well reproduced. To remove the limitation of the small cell size of the FPMD, the classical molecular-dynamics simulations with a cell size of 2197 particles were performed by incorporating the present experimental structural information of liquid Sn. Obtained D's are in good agreement with the microgravi