Cluster-Based Polarized Spectrum Sharing in Channels with Polarization Mode Dispersion

Dongming Li,Zhimin Zeng,Caili Guo,Xiaolin Lin 한국전자통신연구원 2014 ETRI Journal Vol.36 No.3

Polarized spectrum sharing (PSS) exploits the spectrumopportunities in a polarized domain. However, when it comesto wideband environments PSS is impaired by the frequencydependentpolarization mode dispersion (PMD); thus, theeffective throughput of PSS drops. To combat the PMD effect,this work proposes a cluster-based PSS approach to enablePSS on a narrower frequency span. Simulation results showthat the effective throughput of PSS on cluster basisoutperforms that of PSS on bandwidth and subcarrier basis.

China's pension finance under the background of digital transformation Research on promoting high-quality economic developmen

Dongming Yang HONG KONG ACADEMY OF SOCIAL SCIENCES 2024 Journal of Social Science Development Research Vol.1 No.2

Under the background of digital transformation, the development of pension finance in China is of great significance to promote high-quality economic development. At present, the chaos of the pension market and the underdevelopment of pension finance not only lead to the low efficiency of resource utilization, but also increase the pressure of pension risk and social security. The development of pension finance can be said to be more than one stroke, especially in the context that China's economy is currently in the context of transformation and upgrading that requires high-quality development. This paper deeply studies the development path of pension finance and its role in promoting high-quality economic development under the background of digital transformation. The research results show that by constructing a digital pension financial service platform, promoting the deep integration of pension finance and capital market, strengthening risk management and supervision, promoting international development, and improving relevant systems and laws and regulations, we can optimize the allocation of resources, promote innovation, promote consumption upgrading, and provide solid financial support for high- quality economic development. Therefore, strengthening the development of pension finance under the background of digital transformation has important practical significance for promoting the high-quality development of China’s economy.

Constraint-plane-based synthesis and topology variation of a class of metamorphic parallel mechanisms†

Dongming Gan,Jian S Dai,Jorge Dias,Lakmal Seneviratne 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.10

This paper investigates various topologies and mobility of a class of metamorphic parallel mechanisms synthesized with reconfigurablerTPS limbs. Based on the reconfigurable Hooke (rT) joint, the rTPS limb has two phases which result in parallel mechanisms havingability of mobility change. While in one phase the limb has no constraint to the platform, in the other it constrains the spherical joint centerto lie on a plane which is used to demonstrate different topologies of the nrTPS metamorphic parallel mechanisms by investigatingvarious relations (parallel or intersecting) among the n constraint planes (n = 2,3,..,6). Geometric constraint equations of the platformrotation matrix and translation vector are set up based on the point-plane constraint, which reveals mobility and redundant geometricconditions of the mechanism topologies. By altering the limbs into the non-constraint phase without constraint plane, new mechanismphases are deduced with mobility change based on each mechanism topology.

Research of Maize Seeds Classification Recognition Based on the Image Processing

Dongming Li,Yongfu Liu,Liang Gao 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.11

The maize seeds recognition is an important aspect of the seed quality testing and breeding. With the development of computer technology, it is an inevitable tendency to recognize seeds varieties and inspect quality using machine vision instead of human vision. For the characteristics of maize seeds and their images, seeds varieties recognition technology and algorithm was studied and explored in depth and their shape and color feature parameters were extracted. Based on 4 species including Nongda 108, Zhengdan 958, Ludan 981 and Jingdan 28, the classifier was designed using BP neural network to do varieties recognition testing. Research showed the average recognition accuracy was more than 94.5%, and that recognition and detection of maize seeds varieties based on the image technology is feasible.

Review : The Role of Residues 103, 104, and 278 in the Activity of SMG1 Lipase from Malassezia globosa: A Site-Directed Mutagenesis Study

( Dongming Lan ),( Qian Wang ),( Grzegorz Maria Popowicz ),( Bo Yang ),( Qingyun Tang ),( Yonghua Wang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.11

The SMG1 lipase from Malassezia globosa is a newly found mono- and diacylglycerol (DAG) lipase that has a unique lid in the loop conformation that differs from the common alpha-helix lid. In the present study, we characterized the contribution of three residues, L103 and F104 in the lid and F278 in the rim of the binding site groove, on the function of SMG1 lipase. Sitedirected mutagenesis was conducted at these sites, and each of the mutants was expressed in the yeast Pichia pastoris, purified, and characterized for their activity toward DAG and pnitrophenol (pNP) ester. Compared with wild-type SMG1, F278A retained approximately 78% of its activity toward DAG, but only 11% activity toward pNP octanoate (pNP-C8). L103G increased its activity on pNP-C8 by approximately 2-fold, whereas F104G showed an approximate 40% decrease in pNP-C8 activity, and they both showed decreased activity on the DAG emulsion. The deletion of 103-104 retained approximately 30% of its activity toward the DAG emulsion, with an almost complete loss of pNP-C8 activity. The deletion of 103-104 showed a weaker penetration ability to a soybean phosphocholine monolayer than wild-type SMG1. Based on the modulation of the specificity and activity observed, a pNP-C8 binding model for the ester (pNP-C8, N102, and F278 form a flexible bridge) and a specific lipidanchoring mechanism for DAG (L103 and F104 serve as “anchors” to the lipid interface) were proposed.

Seismic Performance Evaluation of the Highway N High-Voltage Substation

Dongming Yan,Jianbo Li,Genda Chen 한국강구조학회 2015 International Journal of Steel Structures Vol.15 No.1

In this study, the Highway N Substation in Missouri was studied with finite element method for its vulnerability underseismic loading. The component of the substation system was modeled with due considerations of mass, stiffness andgeometries. Full-scale shake table experiments were carried out on three electric switches to partially validate the finite elementmodel (FEM). After a systematical modal analysis based on the FEM, response spectrum analyses were performed tocharacterize the dynamic behavior of ‘rigid’ buses and switches of the structure. In time-history analysis, two methods wereemployed to generate the seismic motions: 1) site-specific synthetic ground motion and 2) spectrum compatible ground motion. The results from both ground motions were analyzed and the magnitude and location of the maximum moments in each casewere identified. The effect of slip joints on switches was examined and the maximum relative displacement under the seismicloads was identified.

Exponential Stability of Two Timoshenko Arms for Grasping and Manipulating an Object

Dongming Wu,Takahiro Endo,Fumitoshi Matsuno 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.3

This paper discusses a grasping, orientation, and position control of an object by two flexible arms modeled by the Timoshenko beam. By utilizing our previously proposed controller for the cooperative control, we realize to control the grasping force, orientation, and position of an object as well as to suppress the vibration of the flexible arms. In particular, the closed-loop system is formulated in a Hilbert space, and the exponential stability of the closed-loop system is shown by the frequency domain method. The lightweight flexible arm has intrinsicelastic compliance, and thus the grasping by the flexible arms is safer than that by the rigid arms. In addition, the exponential stability of the closed-loop system contributes to the performance improvement of the grasping and manipulation of an object. Finally, experiments are conducted to confirm the validity of the stability analysis.

Fischer-Tropsch synthesis over ordered mesoporous Co₃O₄ oxides: Effect of Sn promoter to product distribution

( Shen Dongming ),배종욱 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.0

A lot of chemical or structural promoters have been generally used to enhance catalytic activity and stability of the cobalt-based Fischer-Tropsch synthesis (FTS) catalysts. However, among the many promoters on the Co-based FTS catalysts, the effects of Sn promoter have not been well reported till now. In this present study, the effects of Sn promoter on the ordered mesoporous Co₃O₄ metal oxides (meso-Co₃O₄) were investigated for FTS reaction, where the ordered mesoporous Co₃O₄ was made by using KIT-6 hard template. The bulk and surface electronic properties of the Sn-modified meso-Co₃O₄ revealed a higher C₅₊ selectivity at an optimal amount of Sn promoter. The results revealed that the addition of the Sn suppressed water gas shift (WGS) reaction and decreased the selectivity of undesirable CH₄, which seem to be beneficial to increase the carbon efficiency as well.

Ordered mesoporous Iron based catalyst for CO₂ hydrogenation to light olefin

( Shen Dongming ),배종욱 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Carbon dioxide capture and conversion to value-added chemicals is very attractive because it can not only reduce the effect of global warming but also provide a reversible way to produce the fuels and chemicals. Among the of them, the light olefin (C₂-C₄ olefin) is the most important bulk chemicals as the key raw material for chemical intermediates and polymers reliant. In this study, the ordered-mesoporous Iron based catalyst was investigated for the activity of CO₂ hydrogenation to olefin. The physical and electronic properties of the catalyst were verified by N₂-adsorption, H₂-TPR, XRD, and XPS analysis and the optimum catalytic activity were tested by fixed bed reactor at different condition.

A piezoelectric linear ultrasonic motor with the structure of a circular cylindrical stator and slider

Sun, Dongming,Wang, Sheng,Sakurai, Junpei,Choi, Kee-Bong,Shimokohbe, Akira,Hata, Seiichi Institute of Physics Publishing 2010 Smart materials & structures Vol.19 No.4

<P>A piezoelectric linear ultrasonic motor is proposed, with a cylindrical stator and slider structure. The length and diameter of the motor are about 10 and 1.5 mm, respectively. The stator consists of two piezoelectric ceramic (PZT) tubes connected by a thin film metallic glass (TFMG) pipe. The stator is designed based on theoretical analyses and finite element method (FEM) simulation. The traveling wave propagation is obtained in the FEM simulation under the proper geometrical sizes, suitable boundary conditions and driving voltage signals. The trajectories of particles on the TFMG pipe are elliptical motion. In the experiment, a 25  µm thick TFMG pipe is fabricated using the rotating magnetron sputtering technique and the vibration characteristics of the stator are measured by a laser Doppler vibrometer (LDV) system. Bidirectional motion of the slider is observed around 600 kHz, the maximum velocity is near to 40  mm s<SUP> − 1</SUP> at 50 Vp–p for the loose slider and the maximum output force is 6 mN at 70 Vp–p for the tight slider. </P>