Hương Vinh社の立村過程

VĂN HÓA - LỊCH SỬ HUẾ QUA GÓC NHÌN LÀNG XÃ PHỤ CẬN VÀ QUAN HỆ VỚI BÊN NGOÀI 　フエの文化と歴史：周辺集落と外部との関係からの視点より　Session 1: Huong Vinh Land with town-harbour Thanh Ha-Bao Vin

Understanding Interaction Capacity of CO2 with Organic Compounds at Molecular Level: A Theoretical Approach

In this chapter, interactions of CO2 with a number of organic compounds at molecular level are discussed in detail. The naked and substituted hydrocarbons along with compounds functionalized by hydroxyl, carbonyl, thiocarbonyl, carboxyl, sulfonyl, and amide groups have attracted much attention as CO2-philic agents. In general, interaction capacity between the functionalized organic compounds with CO2 is stronger than the hydrocarbon and its derivatives. An addition of more CO2 molecules into the interaction system formed by the functionalized organic compounds and CO2 leads to an increase in the stability of the complexes. The obtained results indicate that π…π linkages between CO2 and aromatic rings can significantly contribute to the interactions between CO2 and MOF/ZIF materials. Formic acid (HCOOH) is likely to be the most soluble compound as compared to the remaining host molecules (CH3OH, CH3NH2, HCHO, HCOOCH3, and CH3COCH3) when dissolved in CO2. The carbonyl (>C═O, >C═S) and sulfonyl (>S═O, >S═S) compounds have presented a higher stability, as compared to other functionalized groups, when they interact with CO2. Therefore, they can be valuable candidates in the design of CO2-philic materials and in the search of materials to adsorb CO2

A thorough theoretical investigation into complexes formed by interaction of dimethyl sulfoxide with two water molecules

A computational study of the stability and the cooperative effect of hydrogen bonds in the complexes of dimethyl sulfoxide and two water molecules was undertaken at the MP2/6-311++G(2d,2p) level of theory. The cooperative energies of obtained complexes are significantly negative, indicating that there is a large cooperativity between types of hydrogen bonds. The existence of the O−H∙∙∙O hydrogen bond present at dimer of water increases the stability of O−H∙∙∙O and C−H∙∙∙O hydrogen bonds in the ternary complexes compared to relevant binary complexes. By vibrational and NBO analyses, it is found that the magnitude of stretching frequency red shift of O−H bonds in the O−H···O hydrogen bonds is enhanced, whereas the extent of stretching frequency blue shift of C−H bonds in the C−H∙∙∙O hydrogen bonds is weakened when the cooperativity of hydrogen bonds happens in the ternary complexes. Obtained results of AIM analysis and stabilization energies indicate the larger contribution of the O−H∙∙∙O relative to the C−H∙∙∙O hydrogen bond to cooperativity. Keywords. Dimethyl sulfoxide, hydrogen bond, cooperativity

A Deep Neural Network Model for Realtime Semantic-Segmentation Video Processing supported to Autonomous Vehicles

Traffic congestion has been a huge problem, especially in urban area during peak hours, which causes a major problem for any unmanned/autonomous vehicles and also accumulate environmental pollution. The solutions for managing and monitoring the traffic flow is challenging that not only asks for performing accurately and flexibly on routes but also requires the lowest installation costs. In this paper, we propose a synthetic method that uses deep learning-based video processing to derive density of traffic object over infrastructure which can support usefull information for autonomous vehicles in a smart control system. The idea is using the semantic segmentation, which is the process of linking each pixel in an image to a class label to produce masked map that support collecting class distribution among each frame. Moreover, an aerial dataset named Saigon Aerial with more than 110 samples is also created in this paper to support unique observation in a biggest city in Vietnam, HoChiMinh city. To present our idea, we evaluated different semantic segmentation models on 2 datasets: Saigon Aerial and UAVid. Also to track our model’s performance, F1 and Mean Intersection over Union metrics are also taken into account. The code and dataset are uploaded to Github and Kaggle repository respectively as follow: Saigon Aerial Code, Saigon Aerial dataset

VEGAS: a variable length-based genetic algorithm for ensemble selection in deep ensemble learning.

In this study, we introduce an ensemble selection method for deep ensemble systems called VEGAS. The deep ensemble models include multiple layers of the ensemble of classifiers (EoC). At each layer, we train the EoC and generates training data for the next layer by concatenating the predictions for training observations and the original training data. The predictions of the classifiers in the last layer are combined by a combining method to obtain the final collaborated prediction. We further improve the prediction accuracy of a deep ensemble model by searching for its optimal configuration, i.e., the optimal set of classifiers in each layer. The optimal configuration is obtained using the Variable-Length Genetic Algorithm (VLGA) to maximize the prediction accuracy of the deep ensemble model on the validation set. We developed three operators of VLGA: roulette wheel selection for breeding, a chunk-based crossover based on the number of classifiers to generate new offsprings, and multiple random points-based mutation on each offspring. The experiments on 20 datasets show that VEGAS outperforms selected benchmark algorithms, including two well-known ensemble methods (Random Forest and XgBoost) and three deep learning methods (Multiple Layer Perceptron, gcForest, and MULES)

The blue shifts of the C-H and N-H bonds in the complexes of CHX3 (X = F, Cl, Br) and HNO: a theoretical study

All calculations were performed at the high level of theory (MP2/6-311++G(d,p)). Five separate minima were identified on the potential energy surface of each complex pairing CH3X with HNO. In general, strength of complexes increases in going from F to Cl to Br, which is consistent with respective decrease of deprotonation enthalpy of the C-H bond respectively. All the C-H and N-H bonds are shortened upon complexation, corresponding to increase in their stretching frequencies. It is interesting that blue shift is observed in the N-H bonds; such a contraction in the N-H covalent bond is extremely rare. Linear correlation between change of stretching frequencies and change of the N-H and C-H bond lengths in all complexes has been reported in equation (1) and (2). Besides, the change of the N-H bond lengths and their stretching frequencies as a function of the change of occupation of σ*(N-H) orbitals and that of s-character of N hybrid orbitals were obtained as in expression (3) and (4)

Revisiting conventional noncovalent interactions towards a complete understanding: from tetrel to pnicogen, chalcogen, and halogen bond

Typical noncovalent interactions, including tetrel (TtB), pnicogen (PniB), chalcogen (ChalB), and halogen bonds (HalB), were systematically re-investigated by modeling the N⋯Z interactions (Z = Si, P, S, Cl) between NH$_3$ – as a nucleophilic, and SiF$_4$, PF$_3$, SF$_2$, and ClF – as electrophilic components, employing highly reliable ab initio methods. The characteristics of N⋯Z interactions when Z goes from Si to Cl, were examined through their changes in stability, vibrational spectroscopy, electron density, and natural orbital analyses. The binding energies of these complexes at CCSD(T)/CBS indicate that NH$_3$ tends to hold tightly most with ClF (−34.7 kJ mol$^{−1}$) and SiF$_4$ (−23.7 kJ mol$^{−1}$) to form N⋯Cl HalB and N⋯Si TtB, respectively. Remarkably, the interaction energies obtained from various approaches imply that the strength of these noncovalent interactions follows the order: N⋯Si TtB > N⋯Cl HalB > N⋯S ChalB > N⋯P PniB, that differs the order of their corresponding complex stability. The conventional N⋯Z noncovalent interactions are characterized by the local vibrational frequencies of 351, 126, 167, and 261 cm$^{−1}$ for TtB, PniB, ChalB, and HalB, respectively. The SAPT2+(3)dMP2 calculations demonstrate that the primary force controlling their strength retains the electrostatic term. Accompanied by the stronger strength of N⋯Si TtB and N⋯Cl HalB, the AIM and NBO results state that they are partly covalent in nature with amounts of 18.57% and 27.53%, respectively. Among various analysis approaches, the force constant of the local N⋯Z stretching vibration is shown to be most accurate in describing the noncovalent interactions

Remarkable shifts of C(sp2)-H and O-H stretching frequencies and stability of complexes of formic acid with formaldehydes and thioformaldehydes

Thirty‐six stable complexes of formic acid with formaldehydes and thioformaldehydes were determined on the potential energy surface, in which the XCHO···HCOOH complexes are found to be more stable than the XCHS···HCOOH counterparts, with X = H, F, Cl, Br, CH3, NH2. All complexes are stabilized by hydrogen bonds, and their contribution to the total stabilization energy of the complexes increases in going from C‐H···S to C‐H···O to O‐H···S and finally to O‐H···O. Remarkably, a significant blueshift of Csp2‐H bond by 81–96 cm−1 in the Csp2‐H···O hydrogen bond has hardly ever been reported, and a considerable redshift of O‐H stretching frequency by 206–544 cm−1 in the O‐H···O/S hydrogen bonds is also predicted. The obtained results in our present work and previous literatures support that a distance contraction and a stretching frequency blueshift of C‐H bond involving hydrogen bond depend mainly on its polarity and gas phase basicity of proton acceptor, besides the rearrangement of electron density due to complex formation. Markedly, we suggest the ratio of deprotonation enthalpy to proton affinity (R c) as an indicator to prospect for classification of hydrogen bonds. The symmetry adapted perturbation theory results show a larger role of attractive electrostatic term in XO‐n as compared to that in XS‐n and the electrostatic interaction is overwhelming dispersion or induction counterparts in stabilizing XO‐n and XS‐n, with n = 1, 2, 3