Similar Hand Gesture Recognition by Automatically Extracting Distinctive Features

Zeyu Ding,Yanmei Chen,Xinyu Wu,Yen-Lun Chen 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.4

With the flourish development of computer vision technology, hand gesture recognition plays a moreand more vital role in human-computer interaction for its convenient and nonverbal communication. However,confusion caused by similar gestures brings inherent errors when considering enough meaningful gestures in thedatabase. In this paper, an automatic feature extraction for similar gesture recognition is proposed with respect toconfusion arising in similar gestures. Except the orientation feature, four additional innovative features are extractedto distinguish all the similar gestures remarkably in the experimental database containing 10 numbers and 26 letters. Compared with the conventional method that a couple of similar gestures are extracted as a specific feature, theproposed method distinguishes similar gestures with automatic distinctive feature extraction. Experimental resultsshow high recognition rate and versatility of the proposed method.

Characterization and Functional Analysis of Bacillus aryabhattai CY for Acrylic Acid Biodegradation: Immobilization and Metabolic Pathway

Yi Chen,Min Zhao,Liyong Hu,Zeyu Wang,Dzmitry Hrynsphan,Jun Chen 한국생물공학회 2021 Biotechnology and Bioprocess Engineering Vol.26 No.6

Acrylic acid has been widely used in various industrial applications but is harmful to human health and the environment. A novel and efficient degrading acrylic acid bacterium was isolated and identified as Bacillus aryabhattai CY. In this study, batch experiments were conducted to evaluate the biodegradation of acrylic acid by B. aryabhattai CY, which were immobilized in calciumalginate beads under different conditions. The components of the alginate beads were optimized by the response surface method, and the degradation performance of the immobilized cells was determined. Relative to the free cells, experiment results showed that the immobilized cells can achieve complete degradation of 100 mg/L acrylic acid in 24 h under the optimal conditions of SA 6% (w/v), CaCl2 1% (w/v), and immobilization time of 6 h. According to Haldane's model, the maximum specific growth rate (μmax) of the free cells and immobilized cells were 0.165/h and 0.210/h, respectively. Experiment data revealed that acrylic acid showed an inhibitory effect on biodegradation by B. aryabhattai CY, especially at concentration higher than 100 mg/L. Furthermore, the reusability of the immobilized cells revealed that the acrylic acid removal rate was above 93.70% within the eight cycles. The immobilized cells also showed higher removal efficiencies in wider ranges of temperature (20°C-60°C) and pH (5.0-10.0) than the free cells. Moreover, the possible degradation intermediates were proposed during the biodegradation of acrylic acid by GC-MS analysis. Results indicated that immobilized beads might have a potential environmental implication in the purification of practical acrylic acid wastewater.

Optimization Coverage of Wireless Sensor Networks Based on Energy Saving

Zeyu Sun,Heng Li,Heng Chen,Wei Wei 보안공학연구지원센터 2014 International Journal of Future Generation Communi Vol.7 No.4

Differentiation of cystic biliary atresia and choledochal cysts using prenatal ultrasonography

Lizhu Chen,Fujiao He,Kaihui Zeng,Bing Wang,Jingyu Li,Dan Zhao,Zeyu Yang,Weidong Ren 대한초음파의학회 2022 ULTRASONOGRAPHY Vol.41 No.1

Purpose: This study explored the performance of prenatal ultrasonography in the differential diagnosis of cystic biliary atresia (CBA) and choledochal cyst (CC). Methods: Fetuses diagnosed with hepatic hilar cyst in the second trimester were included in this study. A series of prenatal ultrasound examinations were performed in the second and third trimesters. The diameter of the gallbladder (GB) and hepatic cyst were measured, as well as the wall thickness of the GB. The GB-cyst connection, visibility of the right hepatic artery (RHA), and other concomitant abnormalities were carefully evaluated. A neonatal transabdominal ultrasound examination was performed within 1 week after birth, and clinical data were followed up to 6 months after birth. Results: Between January 1, 2016 and January 31, 2020, 53 fetuses diagnosed with hepatic hilar cyst were recruited. Eight were excluded because they were lost to follow-up. Among the 45 cases included in this study, 10 were diagnosed with CBA and 35 with CC after birth. Statistically significant differences were found in GB width, wall thickness, change in GB width, change in cyst length, GB-cyst connection, and RHA visibility between the CBA and CC groups. GB width showed the best diagnostic performance with an area under the curve (AUC) of 0.899. The combination of GB width, GB wall thickness, and GB-cyst connection yielded a comparable AUC of 0.971. Conclusion: The GB should be carefully evaluated in fetuses with hepatic hilar cyst. Prenatal ultrasound findings could provide suggestive parameters for the differential diagnosis of CBA from CC. Purpose: This study explored the performance of prenatal ultrasonography in the differential diagnosis of cystic biliary atresia (CBA) and choledochal cyst (CC).Methods: Fetuses diagnosed with hepatic hilar cyst in the second trimester were included in this study. A series of prenatal ultrasound examinations were performed in the second and third trimesters. The diameter of the gallbladder (GB) and hepatic cyst were measured, as well as the wall thickness of the GB. The GB-cyst connection, visibility of the right hepatic artery (RHA), and other concomitant abnormalities were carefully evaluated. A neonatal transabdominal ultrasound examination was performed within 1 week after birth, and clinical data were followed up to 6 months after birth.Results: Between January 1, 2016 and January 31, 2020, 53 fetuses diagnosed with hepatic hilar cyst were recruited. Eight were excluded because they were lost to follow-up. Among the 45 cases included in this study, 10 were diagnosed with CBA and 35 with CC after birth. Statistically significant differences were found in GB width, wall thickness, change in GB width, change in cyst length, GB-cyst connection, and RHA visibility between the CBA and CC groups. GB width showed the best diagnostic performance with an area under the curve (AUC) of 0.899. The combination of GB width, GB wall thickness, and GB-cyst connection yielded a comparable AUC of 0.971.Conclusion: The GB should be carefully evaluated in fetuses with hepatic hilar cyst. Prenatal ultrasound findings could provide suggestive parameters for the differential diagnosis of CBA from CC.

Research on diagnosis method of centrifugal pump rotor faults based on IPSO-VMD and RVM

Dong Liang,Chen Zeyu,Hua Runan,Hu Siyuan,Fan Chuanhan,Xiao xingxin 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.3

Centrifugal pump is a key part of nuclear power plant systems, and its health status is critical to the safety and reliability of nuclear power plants. Therefore, fault diagnosis is required for centrifugal pump. Traditional fault diagnosis methods have difficulty extracting fault features from nonlinear and nonstationary signals, resulting in low diagnostic accuracy. In this paper, a new fault diagnosis method is proposed based on the improved particle swarm optimization (IPSO) algorithm-based variational modal decomposition (VMD) and relevance vector machine (RVM). Firstly, a simulation test bench for rotor faults is built, in which vibration displacement signals of the rotor are also collected by eddy current sensors. Then, the improved particle swarm algorithm is used to optimize the VMD to achieve adaptive decomposition of vibration displacement signals. Meanwhile, a screening criterion based on the minimum Kullback-Leibler (K-L) divergence value is established to extract the primary intrinsic modal function (IMF) component. Eventually, the factors are obtained from the primary IMF component to form a fault feature vector, and fault patterns are recognized using the RVM model. The results show that the extraction of the fault information and fault diagnosis classification have been improved, and the average accuracy could reach 97.87%.

Effects of maternal dietary energy restriction on laying performance, embryonic development, and lipid metabolism in broilers

Sun, Hao,Chen, Zhihui,Ma, Chengzhan,Lian, Lina,Zhao, Zeyu,Niu, Shupeng,Xu, Liangmei,Sun, Jinhua Asian Australasian Association of Animal Productio 2022 Animal Bioscience Vol.35 No.5

Objective: The objective of this study was to investigate the effects of different degrees of maternal dietary energy restriction on lipid deposition in embryonic tissues during the medium laying period (37 to 39 weeks) in Arbor Acres (AA) broiler breeders. Methods: A single factor design was adopted, and 400 AA broiler breeders (20 weeks of age) with a similar weight were randomly allocated into four groups. The birds in the control group were fed a corn-soybean meal based diet, and those in trial groups were fed diets with 80%, 70%, and 50% energy levels of the basal diet. Incubated eggs from the medium laying period were collected. Samples of developing embryos at various stages were prepared for composition analysis. Results: The embryo weight in the 80% energy group was higher than those of the other groups on embryonic day (E) 13, but at 21 E, they were significantly decreased with decreasing energy intake of the broiler breeders (p<0.05). Additionally, the levels of crude fat in tissues in the restriction groups were significantly decreased (p<0.05). The long axis and area of adipocytes in breast muscle, thigh muscle and the liver were significantly decreased (p<0.05) at 21 E in the 80%, 70%, and 50% energy groups. Conclusion: The effects of the 80% maternal dietary energy restriction energy affects egg production performance, egg quality, and nutrient deposition in egg weights, which then directly impacts on the developmental process of embryos, especially on fat utilization and deposition.

mRNA nanodelivery systems: Targeting strategies and administration routes

Mujie Yuan,Zeyu Han,Yan Liang,Yong Sun,Bin He,Wantao Chen,Fan Li 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

With the great success of coronavirus disease (COVID-19) messenger ribonucleic acid (mRNA) vaccines, mRNA therapeutics have gained significant momentum for the prevention and treatment of various refractory diseases. To function efficiently in vivo and overcome clinical limitations, mRNA demands safe and stable vectors and a reasonable administration route, bypassing multiple biological barriers and achieving organ-specific targeted delivery of mRNA. Nanoparticle (NP)-based delivery systems representing leading vector approaches ensure the successful intracellular delivery of mRNA to the target organ. In this review, chemical modifications of mRNA and various types of advanced mRNA NPs, including lipid NPs and polymers are summarized. The importance of passive targeting, especially endogenous targeting, and active targeting in mRNA nano-delivery is emphasized, and different cellular endocytic mechanisms are discussed. Most importantly, based on the above content and the physiological structure characteristics of various organs in vivo, the design strategies of mRNA NPs targeting different organs and cells are classified and discussed. Furthermore, the influence of administration routes on targeting design is highlighted. Finally, an outlook on the remaining challenges and future development toward mRNA targeted therapies and precision medicine is provided.

Natural Flow Characteristics of Liquid Rocket Engine Turbopump during Startup

Runze Zhou,Hui Chen,Liang Dong,Houlin Liu,Linglin Jiang,Zeyu Chen 한국유체기계학회 2022 International journal of fluid machinery and syste Vol.15 No.3

When the liquid rocket engine turbopump starts, the tank valve opens first before the pump is driven. Due to the tank and hydrostatic pressure, there is a passive flow phenomenon inside the pump called natural flow. The impeller is passively rotated by hydraulic impact, which impacts the stability of the turbopump during the initial startup period. In order to study the unsteady natural flow characteristics of the turbopump, the coupled CFD/6DOF solver is used for simulation and obtaining the variation of rotational speed, flow loss, and torque with time. The characteristics of the turbopump impeller's radial and axial force are analyzed. The internal flow field and pressure pulsation features were investigated. The results show that the rotational speed caused by natural flow increases exponentially with time. Furthermore, the natural flow loss and torque gradually decrease with the increased rotational speed and has distinct pulsation characteristics and periodicity. The backflow phenomenon in the flow channel becomes more complex. The suction chamber and the inducer have a buffering effect on the impact of the incoming flow, making the pressure distribution more uniform. Due to the matching angle and the rotor-stator interference, the pressure pulsation in the guide vanes has distinct sub-harmonic interference during the natural flow process.

Spatial mechanical behaviors of long-span V-shape rigid frame composite arch bridges

Gou, Hongye,Pu, Qianhui,Wang, Junming,Chen, Zeyu,Qin, Shiqiang Techno-Press 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.47 No.1

The Xiaolan channel super large bridge is unique in style and with greatest span in the world with a total length of 7686.57 m. The main bridge with spans arranged as 100m+220m+100m is a combined structure composed of prestressed concrete V-shape rigid frame and concrete-filled steel tubular flexible arch. First of all, the author compiles APDL command flow program by using the unit birth-death technique and establishes simulation calculation model in the whole construction process. The creep characteristics of concrete are also taken into account. The force ratio of the suspender, arch and beam is discussed. The authors conduct studies on the three-plate webs's rule of shear stress distribution, the box girder's longitudinal bending normal stress on every construction stage, meanwhile the distribution law of longitudinal bending normal stress and transverse bending normal stress of completed bridge's box girder. Results show that, as a new combined bridge, it is featured by: Girder and arch resist forces together; Moment effects of the structure are mainly presented as compressed arch and tensioned girder; The bridge type brings the girder and arch on resisting forces into full play; Great in vertical stiffness and slender in appearance.

Spatial mechanical behaviors of long-span V-shape rigid frame composite arch bridges

Hongye Gou,Qianhui Pu,Junming Wang,Zeyu Chen,Shiqiang Qin 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.47 No.1

The Xiaolan channel super large bridge is unique in style and with greatest span in the world with a total length of 7686.57 m. The main bridge with spans arranged as 100m+220m+100m is a combined structure composed of prestressed concrete V-shape rigid frame and concrete-filled steel tubular flexible arch. First of all, the author compiles APDL command flow program by using the unit birth-death technique and establishes simulation calculation model in the whole construction process. The creep characteristics of concrete are also taken into account. The force ratio of the suspender, arch and beam is discussed. The authors conduct studies on the three-plate webs’s rule of shear stress distribution, the box girder’s longitudinal bending normal stress on every construction stage, meanwhile the distribution law of longitudinal bending normal stress and transverse bending normal stress of completed bridge’s box girder. Results show that, as a new combined bridge, it is featured by: Girder and arch resist forces together; Moment effects of the structure are mainly presented as compressed arch and tensioned girder; The bridge type brings the girder and arch on resisting forces into full play; Great in vertical stiffness and slender in appearance.