Reflection-type Finger Vein Recognition for Mobile Applications

Congcong Zhang,Zhi Liu,Yi Liu,Fangqi Su,Jun Chang,Yiran Zhou,Qijun Zhao 한국광학회 2015 Current Optics and Photonics Vol.19 No.5

Finger vein recognition, which is a promising biometric method for identity authentication, has attractedsignificant attention. Considerable research focuses on transmission-type finger vein recognition, but thistype of authentication is difficult to implement in mobile consumer devices. Therefore, reflection-type fingervein recognition should be developed. In the reflection-type vein recognition field, the majority ofresearchers concentrate on palm and palm dorsa patterns, and only a few pay attention to reflection-typefinger vein recognition. Thus, this paper presents reflection-type finger vein recognition for biometricapplication that can be integrated into mobile consumer devices. A database is built to test the proposedalgorithm. A novel method of region-of-interest localization for a finger vein image is introduced, anda scheme for effectively extracting finger vein features is proposed. Experiments demonstrate the feasibilityof reflection-type finger vein recognition

Implementation and Calculation of General Electricity Prices on Industry with Fee Charging Terminal

Congcong Li,Zhongyao Zhang,Xiao Liu 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.1

The calculation of general electricity prices on industry has great significance in cost control, energy conservation and emission reduction, as well as high efficiency management of electricity for the key electric power customers. Traditional solution has specific defections in time-consuming, convenience, and readout, however, the fee charging terminal has provided a more reasonable solution in interaction interface and abundant parameters settings with high efficiency.

Fractal Kinetic Analysis of Enzymatic Saccharification of the Acetic Acid Pretreated Acacia

Congcong Chi,Mi Liu,Zhenzhen Hui,Xian Lai 한국펄프·종이공학회 2016 한국펄프·종이공학회 학술발표논문집 Vol.2016 No.10

Reliability Analysis of Unrepairable Systems with Uncertain Lifetimes

Ying Liu,Xiaozhong Li,Congcong Xiong 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.12

The topic of unrepairable system is an important content in system reliability theory. There are many reasons cannot be repaired, some because of technical reasons, cannot repair, some because of economic reasons, not worth to repair, and some because of making repairable system simplification. So it is essential to pay attention to unrepairable systems. In this paper, the lifetimes of unrepairable systems are considered as uncertain variables. Based on that, the fundamental mathematical models of series systems, parallel systems, series-parallel systems and parallel-series systems are established, respectively. Furthermore, we make reliability analysis of above four unrepairable systems, respectively. Some numerical examples are also given for illustration.

Exosomal microRNAs from Mesenchymal Stem Cells: Novel Therapeutic Effect in Wound Healing

Ju Congcong,Liu Dewu 한국조직공학과 재생의학회 2023 조직공학과 재생의학 Vol.20 No.5

BACKGROUND: Wound healing is a complicated biological process that leads to the regeneration of damaged skin tissue. Determining the methods to promote wound healing has become a hot topic in medical cosmetology and tissue repair research. Mesenchymal stem cells (MSCs) are a group of stem cells with the potential of self-renewal and multidifferentiation. MSCs transplantation has a broad application prospect in wound healing therapy. Many studies have demonstrated that the therapeutic capacity of MSCs is mainly mediated by paracrine actions. Exosomes (EXOs), which are nanosized vesicles carrying a variety of nucleic acids, proteins and lipids, are an important component of paracrine secretion. It has been demonstrated that exosomal microRNAs (EXO-miRNAs) play a key role in the function of exosomes. METHODS: In this review, we focus on current research on miRNAs from MSC-derived exosomes (MSC-EXO miRNAs) in terms of sorting, releasing and function and their effects on inflammation regulation, epidermal cell function, fibroblast function, and extracellular matrix formation. At last, we discuss the current attempts to improve the treatment of MSC-EXO-miRNAs. RESULTS: Many studies have demonstrated that MSC-EXO miRNAs play a key role in promoting wound healing. They have been shown to regulate inflammation response, enhance epidermal cell proliferation and migration, stimulate fibroblast proliferation and collagen synthesis, and regulate extracellular matrix formation. Besides, there have been a number of strategies developed to promote MSC-EXO and MSC-EXO miRNAs for wound healing treatment. CONCLUSION: Utilizing the association of exosomes from MSCs with miRNAs may be a promising strategy to promote trauma healing. MSC-EXO miRNAs may provide a new approach to promote wound healing and improve the quality of life for patients with skin injuries.

Electrostatic spraying of membrane electrode for proton exchange membrane fuel cell

Ruiliang Liu,Wei Zhou,Liyang Wan,Pengyang Zhang,Shuangli Li,Yu Gao,Dongsheng Xu,Congcong Zheng,Mingfeng Shang 한국물리학회 2020 Current Applied Physics Vol.20 No.1

In order to improve the performance of proton exchange membrane fuel cell (PEMFC), the optimization of electrostatic spraying of membrane electrode was conducted. The influence of the spraying voltage on morphology, elemental composition of catalyst layer, and performance of the PEMFC were investigated. The results show that increasing spraying voltage could reduce agglomeration of the carbon-supported platinum particles, leading to more uniform pore distribution. High voltage did not accelerate oxidation of platinum catalyst. A high electrochemical active surface area of 26.18m2/gpt was obtained when the platinum-carbon catalyst layer was deposited in cone jet mode. With further increasing spraying voltage, the total ohmic resistance and catalytic activity were changed slightly, whereas the charge transfer resistance was increased. Using the optimized electrostatic spraying parameters (injection rate=100 μL min−1, spraying voltage=8.5 kV, and working distance= 12 mm), a peak power density of 1.408Wcm−2 was obtained with an output voltage of 0.451 V.

A Density Peak Clustering Algorithm Based on Information Bottleneck

Yongli Liu,Congcong Zhao,Hao Chao 한국정보처리학회 2023 Journal of information processing systems Vol.19 No.6

Although density peak clustering can often easily yield excellent results, there is still room for improvementwhen dealing with complex, high-dimensional datasets. One of the main limitations of this algorithm is itsreliance on geometric distance as the sole similarity measurement. To address this limitation, we drawinspiration from the information bottleneck theory, and propose a novel density peak clustering algorithm thatincorporates this theory as a similarity measure. Specifically, our algorithm utilizes the joint probabilitydistribution between data objects and feature information, and employs the loss of mutual information as themeasurement standard. This approach not only eliminates the potential for subjective error in selectingsimilarity method, but also enhances performance on datasets with multiple centers and high dimensionality. To evaluate the effectiveness of our algorithm, we conducted experiments using ten carefully selected datasetsand compared the results with three other algorithms. The experimental results demonstrate that our informationbottleneck-based density peaks clustering (IBDPC) algorithm consistently achieves high levels of accuracy,highlighting its potential as a valuable tool for data clustering tasks.

Improving the Electrical Conductivity of PEDOT:PSS Films by Binary Secondary Doping

Zhengyou Zhu,Congcong Liu,Jingkun Xu,Qinglin Jiang,Hui Shi,Endou Liu 대한금속·재료학회 2016 ELECTRONIC MATERIALS LETTERS Vol.12 No.1

In this work, the electrical conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films was effectively enhanced by binarysecondary doping. Initially, doping with 5 vol.% dimethyl sulfoxide (DMSO)improved the electrical conductivity from 0.3 S cm−1 to 437 S cm−1 and a furtherincrease to 950 S cm−1 was achieved by adding LiClO4. The conductivity value wereport here is one of the highest reported for pretreated PEDOT:PSS films. Theobtained maximum electrical conductivity is almost 3000 times higher than thatshown by pristine PEDOT:PSS films. The increase in the electrical conductivity isascribed to the synergistic effect of the two dopants. Fourier transform infraredspectra indicated the absence of any changes to the chemical structure ofPEDOT:PSS. Atomic force microscopy images demonstrate an increased surfaceroughness and suggest the occurrence of conformational changes of PEDOT chainsfrom the coiled to coil-extended one, which is the key reason for the electricalconductivity enhancement. The pretreatments we propose here are rapid, simple andeffective for the large-scale preparation of high-conductivity PEDOT:PSS films.

Thermoelectric Performance of Poly(3-hexylthiophene) Films Doped by Iodine Vapor with Promising High Seebeck Coefficient

Hongfei Zhu,Congcong Liu,Haijun Song,Jingkun Xu,Fangfang Kong,Jianmin Wang 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.2

Poly(3-hexylthiophene) (P3HT) films doped with iodine vapor have been prepared by casting a P3HT solution on glass substrates and their thermoelectric (TE) performances has been investigated. The maximum Seebeck coefficient and electrical conductivity of iodine-doped P3HT films were 386 μV·K−1 (at room temperature) and 4.7 × 10−1 S·cm−1, which is about five orders of magnitude higher than that of pristine P3HT films. The power factor of these iodine-doped P3HT films was estimated to be 7.0 μW·m−1·K−2 at room temperature, which is a relative high value for organic TE materials. The UV-vis spectra of iodine-doped P3HT films showed a slight red shift of the iodine-doped P3HT compared to those of pristine P3HT films. Atomic force microscopy images indicated the conformational changes in P3HT chains after treatment with iodine vapor. During this treatment, the P3HT chains self-organized into a more ordered structure, this organization improved the charge carrier transport capability and the TE performance of P3HT the films.

Toward efficient broad-spectrum UV absorption of carbon dots: Facile preparation, performance characterization and its application as UV absorbers

Jiemin Qiu,Weihao Ye,Congcong Chen,Zhiqiang Xu,Chaofan Hu,Jianle Zhuang,Hanwu Dong,Bingfu Lei,Guangqi Hu,Yingliang Liu 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.117 No.-

UV absorbers are sustainable substances that inhibit the ultraviolet (UV) radiative degradation of polymers. In previous reports, the as-prepared carbon dots (CDs) possess only an absorption band at UVA(320–400 nm). To achieve broad-spectrum UV absorption (200–400 nm), increasing the concentrationof the CDs solution becomes common. However, a high concentration solution seriously affects the lighttransmittance due to its heavy yellow color. Furthermore, the promising organic UV absorbers cannotachieve broad-spectrum UV absorption. In this work, we initially synthesized three-component watersolublecarbon dots (OP–CDs), which delivers an excellent UV absorption (98 % UVA and 100 % UVB atthe concentration of 1.7 102 mg/mL; 99 % transmittance in visible light). Moreover, OP–CDs exhibitoutstanding stability at high temperatures and different pH. With the corporation of OP–CDs and polyvinylalcohol (PVA), a high-performance UV-shielding film was formed, leading to enhanced broadspectrumUV shielding performance and improved mechanical properties, resistance of photocatalyticactivity and anti-UV aging ability compared with pure PVA film. Notably, the PVA film remains hightransparency with the addition of OP–CDs. The study suggests that the corporation of OP–CDs and polymersis effective in anti-UV degradation.