Proposal of Wind Power Generator using Solar Zero-power Magnetic Suspension

Huajun CHEN,Takeshi MIZUNO,Yuji ISHINO,Daisuke YAMAGUCHI,Masayuki HARA,Masaya TAKASAKI 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.춘계 No.-

Quasi-Two-Dimensional Metal Oxide Semiconductors Based Ultrasensitive Potentiometric Biosensors

Chen, Huajun,Rim, You Seung,Wang, Isaac Caleb,Li, Chao,Zhu, Bowen,Sun, Mo,Goorsky, Mark S.,He, Ximin,Yang, Yang American Chemical Society 2017 ACS NANO Vol.11 No.5

<P>Ultrasensitive field-effect transistor-based biosensors using quasi two -dimensional metal oxide semiconductors were demonstrated. Quasi-two-dimensional low-dimensional metal oxide semiconductors were highly sensitive to electrical perturbations at the semiconductor bio interface and showed competitive sensitivity compared with other nanomaterial-based biosensors. Also, the solution process made our platform simple and highly reproducible, which was favorable compared with other nanobioelectronics. A quasi-two-dimensional In2O3-based pH sensor showed a small detection limit of 0.0005 pH and detected the glucose concentration at femtomolar levels. Detailed electrical characterization unveiled how the device's parameters affect the biosensor sensitivity, and lowest detectable charge was extrapolated, which was consistent with the experimental data.</P>

A Reuse-Oriented Redesign Method of used Machine Tool based on Matter-Element Theory

Huajun Cao,Xiang Chen,Lei Xu,Enxu Ma 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

Aiming at the remanufacturing of used machine tool, a reuse-oriented redesign method was presented. The function tree of machinetool was established on the basis of machine tool’s characteristics of the function and structure in the method. The matter-elementmodel of sub-function was built with the matter-element theory, and then the redesign alternatives of sub-functions were made byfinding and removing the differences between the corresponding matter-element of sub-functions. The redesign alternatives of machinetool were built by combining the redesign alternatives of every sub-function together organically. For obtaining the best alternative,a comprehensive evaluation method was proposed based on the correlation function, the Analytic Hierarchy Process (AHP) and theremanufacturing knowledge of used machine tool. The evaluation method includes four indexes, such as the cost (C), the time (T),the rate of reuse (R) and the overall performance (P). Finally, this reuse-oriented redesign method was applied in one floor-typemilling & boring machine’s remanufacturing in an enterprise, and its effectiveness was verified.

The inhibitory effect of gut microbiota and its metabolites on colorectal cancer

Chen Chao,Huajun Li 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.11

Colorectal cancer (CRC) is regarded as one of the most common and deadly forms of cancer. Gut microbiota is vital to retain and promote several functions of intestinal. Although previous researches have shown that some gut microbiota have the abilities to inhibit tumorigenesis and prevent cancer from progressing, they have not yet clearly identified associative mechanisms. This review not only concentrates on the antitumor effects of metabolites produced by gut microbiota, for example, SCFA, ferrichrome, urolithins, equol and conjugated linoleic acids, but also the molecules which constituted the bacterial cell wall have the antitumor effect in the host, including lipopolysaccharide, lipoteichoic acid, β-glucans and peptidoglycan. The aim of our review is to develop a possible therapeutic method, which use the products of gut microbiota metabolism or gut microbiota constituents to help treat or prevent colorectal cancer.

Cloning and Characterization of 6-Phosphogluconolactonase Gene in Silkworm Bombyx mori

Yang, HuaJun,Chen, KePing,Yao, Qin,Guo, ZhongJian Korean Society of Sericultural Science 2007 International Journal of Industrial Entomology Vol.14 No.2

As the genome of B. mori is available in GenBank and the EST database of B. mori is expanding, identification of novel genes of B. mori was conceivable by datamining techniques and bioinformatics tools. In this study, we used the in silico cloning method to get the 6-Phosphogluconolactonase (6PGL) gene of B. mori and analysed with bioinformatics tools. The result was confirmed by RT-PCR and prokaryotic expression. The 6PGL cDNA comtains a 702 bp ORF. The deduced protein has 233 amino acid residues, with the predicted molecular weight of 25946. 72 Da, isoelectric point of 5.41, and contains conserved NagB domains. This gene has been registered in GenBank under the accession number EF198104.

An adaptive parameter optimization model and system for sustainable gear dry hobbing in batch production

Ying Zhang,Huajun Cao,Peng Chen,Li-Bin Zhu,Xiao Yang 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.6

Gear hobbing technology is one of the most widely used forming processes of gear teeth. And the development of dry hobbing technologyprovides a solution for realizing productive, economical, and ecological gear production. Since there is no cutting oil for coolingand lubrication in dry hobbing process, the hob tool life, thermal deformation errors of machine tool, and quality of workpiece are sensitiveto the cutting parameters, especially the cutting speed and tip chip thickness. Considering this situation, a dry hobbing parametersoptimization model with the hobbing efficiency as our objective, and the hobbing cost per piece, gear quality, tact time as constraints wasestablished, in which the cutting speed and tip chip thickness were considered as optimal variables and the material of workpiece, coatingof hob, and feed rate were considered comprehensively. An iterative test method is proposed to solve this model. And for the applicationin automated production line, an online adaptive application system was also developed based on SINUMERIK 840D NC system. Theparameters of five different kinds of material gear were optimized by applying this model and system, and the result showed the modeland the system were practical.

An Analytical Model of Chip Heat-Carrying Capacity for High-Speed Dry Hobbing Based on 3D Chip Geometry

Xiao Yang,Huajun Cao,Yong-peng Chen,Li-Bin Zhu,Ben-jie Li 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.2

High-speed dry hobbing is the dominating green technique for gear hobbing owing to its high productivity and environmental friendliness. However, a large amount of cutting heat is generated during the machining process due to the absence of metalworking fluids and the adoption of high cutting speed. A better understanding of chip heat-carrying capacity for high-speed dry hobbing is quite necessary when aiming to reduce the influence of cutting heat on machining precision. In this paper, an analytical model is established to quantitatively determine the chip heat-carrying capacity of high-speed dry hobbing. According to the progressive heat transfer characteristic of high-speed dry hobbing, cutting heat generation and transmission are analyzed. 3D chip geometry is numerically calculated by modeling the complex hob geometry and the interrelated kinematic relations of high-speed dry hobbing. Based on the 3D chip geometry and the specific cutting energy, chip heat-carrying capacity model is developed considering three heat sources. In this model, chip heat partition is experimentally determined by calorimetric method. With the help of the developed model, chip heat-carrying quantity and chip heat-carrying efficiency are discussed by investigating their influence factors (hob rotation speed, axial feed, feed method, chip removal time and hob geometry).

Quasi-static test of the precast-concrete pile foundation for railway bridge construction

Zhang, Xiyin,Chen, Xingchong,Wang, Yi,Ding, Mingbo,Lu, Jinhua,Ma, Huajun Techno-Press 2020 Advances in concrete construction Vol.10 No.1

Precast concrete elements in accelerated bridge construction (ABC) extends from superstructure to substructure, precast pile foundation has proven a benefit for regions with fragile ecological environment and adverse geological condition. There is still a lack of knowledge of the seismic behavior and performance of the precast pile foundation. In this study, a 1/8 scaled model of precast pile foundation with elevated cap is fabricated for quasi-static test. The failure mechanism and responses of the precast pile-soil interaction system are analyzed. It is shown that damage occurs primarily in precast pile-soil interaction system and the bridge pier keeps elastic state because of its relatively large cross-section designed for railways. The vulnerable part of the precast pile with elevated cap is located at the embedded section, but no plastic hinge forms along the pile depth under cyclic loading. Hysteretic curves show no significant strength degradation but obvious stiffness degradation throughout the loading process. The energy dissipation capacity of the precast pile-soil interaction system is discussed by using index of the equivalent viscous damping ratio. It can be found that the energy dissipation capacity decreases with the increase of loading displacement due to the unyielding pile reinforcements and potential pile uplift. It is expected to promote the use of precast pile foundation in accelerated bridge construction (ABC) of railways designed in seismic regions.

Physical Internet-Enabled Manufacturing Execution System for Intelligent Workshop Production

Ray Y. Zhong,Huajun Gong,Chen Xu,Shaoping Lu 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.6

A Physical Internet-enabled Manufacturing Executive System (PIMES) is proposed for intelligent workshop production. PIMES uses Radio Frequency Identification (RFID), 433MHZ wireless communication, and Physical Internet concept to create a ubiquitous production environment where real-time data could be collected and then converted into dynamic feedback factors sent back to the system. PIMES includes several services such as Production Decision Service, Communication Control Service, Visibility Service, and Interface Service which are designed and developed by making full use of the service-oriented architecture (SOA) and Cloud technology. With the assistance of these services, PIMES is able to achieve several outperformances upon traditional production systems like paperless operations, real-time decision-making, automatic statistics and reporting, as well as visualized manufacturing control and management. After the implementation of PIMES, workshop production of a case enterprise is streamlined and optimized by making full use of the collected data to support the workshop production and logistics.

Boosting Responsivity of Organic–Metal Oxynitride Hybrid Heterointerface Phototransistor

Rim, You Seung,Ok, Kyung-Chul,Yang, Yang Michael,Chen, Huajun,Bae, Sang-Hoon,Wang, Chen,Huang, Yu,Park, Jin-Seong,Yang, Yang American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.23

<P>Amorphous metal oxides are attractive materials for various sensor applications, because of high electrical performance and easy processing. However, low absorption coefficient, slow photoresponse, and persistent photoconductivity of amorphous metal oxide films from the origin of deep-level defects are obstacles to their use as photonic applications. Here, we demonstrate ultrahigh photoresponsivity of organic-inorganic hybrid phototransistors featuring bulk heterojunction polymers and low bandgap zinc oxynitride. Spontaneous formation of ultrathin zinc oxide on the surface of zinc oxynitride films could make an effective band-alignment for electron transfer from the dissociation of excitons in the bulk heterojunction, while holes were blocked by the deep highest occupied molecular orbital level of zinc oxide. These hybrid structure-based phototransistors are ultrasensitive to broad-bandwidth photons in ultraviolet to near infrared regions. The detectivity and a linear dynamic range exceeded 10(12) Jones and 122.3 dB, respectively.</P>