Improved Particle Swarm Optimization Algorithm for Adaptive Frequency-Tracking Control in Wireless Power Transfer Systems

Yang Li,Liu Liu,Cheng Zhang,Qingxin Yang,Jianxiong Li,Xian Zhang,Ming Xue 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

Recently, wireless power transfer (WPT) via coupled magnetic resonances has attracted a lot of attention owing to its long operation distance and high efficiency. However, the WPT systems is over-coupling and a frequency splitting phenomenon occurs when resonators are placed closely, which leads to a decrease in the transfer power. To solve this problem, an adaptive frequency tracking control (AFTC) was used based on a closed-loop control scheme. An improved particle swarm optimization (PSO) algorithm was proposed with the AFTC to track the maximum power point in real time. In addition, simulations were carried out. Finally, a WPT system with the AFTC was demonstrated to experimentally validate the improved PSO algorithm and its tracking performance in terms of optimal frequency.

Analysis and Optimization of the Working Parameters of the Impact Mechanism of Hydraulic Rock Drill Based on a Numerical Simulation

Shuyi Yang,Yang-bin Ou,Yong Guo,Xian-ming Wu 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.7

An impact system is the core part of the hydraulic rock drill. The dynamic simulation model of the hydraulic impact system is established based on the system simulation platform AMEsim. We used the AMEsim simulation model to verify the displacement, velocity curves of the piston, and valve by using stress wave testing data. The following key features of the impact system are determined: the characteristic curves of the pressure variations in the piston chambers, the influences of oil flow, the charging pressures of the high-pressure accumulator, the pre-setting pressure of the relief valve on impact performance, and impact efficiency. On the basis of orthogonal experiments, a response surface method is used to build a mathematical model of the impact system with efficient and various working parameters. The impact system with an optimal efficiency is designed, and the working parameters are optimized. Our proposed system efficiency increases by 17.7% after the working parameters are optimized. This study provides a theoretical basis for the design and optimization of the impact system parameters of the hydraulic rock drill with a sleeve valve.

Electrochemical control of the conversion of cellulose oligosaccharides into glucose

Fang Yang,Qian Zhang,Hong-Xian Fan,Yang Li,Gang Li 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

This paper presents a novel method to convert cellulose oligosaccharides to glucose by using constant-potential electrolysis. Firstly experiments were performed to seek the optimum conditions and catalyst dosage to make the catalytic electrode, and it is found that the most active catalytic electrode (g-MnO2/graphite/PTFE) can be made using 5% g-MnO2 as catalysts which is prepared at calcinations temperature of 500 8C and calcinations time of 3 h. Following this, experiments were conducted to find the optimum operation conditions for the maximum glucose yield using the above-developed catalytic electrode. The results show that the maximum glucose yield of 72.4% can be achieved under the following operation conditions: electrolysis potential vs. SEC 1.0 V, pH value of 3 and electrolytic reaction time of 8 h. The cyclic voltammetry performance on MnO2/graphite/PTFE electrode suggests that g-MnO2 acts not only as electrode material but also as a catalyst. The g-MnO2 displays high electrocatalytic activity toward the breakage of b-1,4-glycoside bond of oligosaccharides and gives 100% selectivity to glucose. Crown Copyright

Endoscopic Diagnosis of Nonpedunculated Dysplasia during Surveillance of Ulcerative Colitis: A Survey-Based Multinational Study

Dong-Hoon Yang,Sneha John,Fujishiro Mitsuhiro,Jae Myung Cha,Jeong-Sik Byeon,Hyung Wook Kim,Hyun Gun Kim,Shai Friedland,Yon Xian Koh,Jin-Young Yoon,Min-Seob Kwak,Byong Duk Ye,Jihun Kim,Suk-Kyun Yang 거트앤리버 소화기연관학회협의회 2020 Gut and Liver Vol.14 No.5

Background/Aims: Endoscopic diagnosis of dysplasia or colitic cancer in patients with ulcerative colitis (UC) is more challenging than that of colorectal neoplasia in non-colitic patients. We aimed to evaluate the accuracy of the endoscopic diagnosis of “nonpedunculated” dysplasia or colitic cancer in UC patients. Methods: Ten endoscopists from four countries were surveyed using photographs of 61 histologically confirmed dysplastic or non-dysplastic lesions retrieved from the UC registry database of Asan Medical Center. The participants provided their assessment based on the given photographs and their intention to perform biopsy. Results: The overall diagnostic performance of the 10 participants is summarized as follows: sensitivity of 88.2% (95% confidence interval [CI], 84.3% to 91.5%), specificity of 34.8% (95% CI, 29.1% to 40.8%), positive predictive value of 63.0% (95% CI, 60.8% to 65.2%), negative predictive value of 70.2% (95% CI, 62.7% to 76.6%), and accuracy of 64.6% (95% CI, 60.7% to 68.4%). The interobserver agreement on the intention to perform a biopsy was poor (Fleiss kappa=0.169). Of the three endoscopic characteristics of the lesions, including ulceration, distinctness of the borders, and pit patterns, only neoplastic pit patterns were significantly predictive of dysplasia (odds ratio, 3.710; 95% CI, 2.001 to 6.881). The diagnostic sensitivity and specificity of neoplastic pit patterns were 68.2% (95% CI, 63.0% to 73.2%) and 63.3% (95% CI, 57.3% to 69.1%), respectively. Conclusions: Diagnostic performance based on the endoscopist’s intention to perform a biopsy for nonpedunculated potentially dysplastic lesions in UC patients was suboptimal according to this survey-based study.

The Growing Problem of Radiologist Shortages: Perspectives From Singapore

Goh Charles Xian Yang,Ho Francis Cho Hao 대한영상의학회 2023 Korean Journal of Radiology Vol.24 No.12

Isoindolin-1-ones from the stems of Nicotiana tabacum and their antiviral activities

Guang-Yu Yang,Jia-Meng Dai,Zhen-Jie Li,Jin Wang,Feng-Xian Yang,Xin Liu,Jing Li,Qian Gao,Xue-Mei Li,Yin-Ke Li,Wei-Guang Wang,Min Zhou,Qiu-Fen Hu 대한약학회 2022 Archives of Pharmacal Research Vol.45 No.8

In previous studies, several isoindolin-1-oneanalogs that exhibited signifi cant anti-tobacco mosaic virus(anti-TMV) activities were isolated from Nicotiana tabacum . Since gene-editing mutants provide a new sample for thediscovery of active metabolites, we focused on the stems ofYN-18–23 (a mutant N. tabacum for gene editing with thealkaloid metabolic pathway cultivated by Yunnan TobaccoCompany), which led to the isolation of four new ( 1–4 )and four known ( 5–8 ) isoindolin-1-ones. To the best of ourknowledge, nicindole C ( 3 ) is the fi rst subclass of isoindolin-1-one bearing a pentacyclic ketone, while nicindole D ( 4 )is the fi rst example of isoindolin-1-one bearing a methylpyridin-2-(1 H )-one moiety. Compounds 1–4 were testedfor their anti-TMV activities, and the results revealed thatcompounds 1 , 3 , and 4 exhibited high anti-TMV activities atconcentrations of 20 μM with inhibition rates of 48.6, 42.8,and 71.5%, respectively. These rates are higher than the inhibitionrate of the positive control (33.2%). The mechanisticstudy of compound 4 , which had the highest anti-TMV activityrevealed that increased potentiation of defense-related enzyme activities and downregulation of expression of theNtHsp70 protein may induce resistance in tobacco againstthe viral pathogen TMV. Molecular docking studies alsorevealed that the isoindolin-1-one substructure is fundamentalfor anti-TMV activity. The methyl-pyridin-2-(1 H )-onemoiety in compound 4 and the 2-oxopropyl groups in compounds1 and 3 at the N -2 position may increase inhibitoryactivities. This study of the structure–activity relationshipis helpful for fi nding new anti-TMV activity inhibitors. Tostudy whether the isoindolin-1-ones have broader antiviralactivities, compounds 1–4 were also tested for their antirotavirusactivities. Compound 4 exhibited high anti-rotavirusactivity with a therapeutic index (TI) value of 20.7. This TI value is close to that of the positive control (20.2).

A Novel Missense Mutation of Keratin 17 Gene in a Chinese Family with Steatocystoma Multiplex

( Wei Wei Ha ),( Jing Wang ),( Wen Wang ),( Hong Yang Fu ),( Hua Yang Tang ),( Xian Fa Tang ),( Jun Zhu ),( Xian Yong Yin ),( Sen Yang ),( Xue Jun Zhang ) 대한피부과학회 2013 Annals of Dermatology Vol.25 No.4

LETTER TO THE EDITOR : One Mutation of the ED1 Gene in a Chinese Han Family with X-Linked Hypohidrotic Ectodermal Dysplasia

( Jing Wang ),( Wei Wei Ha ),( Wen Wang ),( Hua Yang Tang ),( Xian Fa Tang ),( Xian Dong Zheng ),( Jun Zhu ),( Xian Yong Yin ),( Sen Yang ),( Xue Jun Zhang ) 대한피부과학회 2014 Annals of Dermatology Vol.26 No.1

Degradation kinetics of vitamins in premixes for pig: effects of choline, high concentrations of copper and zinc, and storage time

Yang Pan,Wang Hua Kai,Zhu Min,Li Long Xian,Ma Yong Xi 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.4

Objective: The present work was undertaken to evaluate the effects of storage time, choline chloride, and high concentrations of Cu and Zn on the kinetic behavior of vitamin degradation during storage in two vitamin premixes and four vitamin-trace mineral (VTM) premixes. Methods: Two vitamin premixes (with or without 160,000 mg/kg of choline) were stored at 25°C and 60% humidity. Besides, four VTM premixes were used to evaluate the effects of choline (0 vs 40,000 mg/kg) and trace minerals (low CuSO4+ZnO vs high CuSO4+ZnO) on vitamin stability in VTM premixes stored in room, and the VTM premixes were stored in room temperature at 22°C. Subsamples from each vitamin and VTM premix were collected at 0, 1, 2, 3, 6, and 12 months. The retention of vitamin A (VA), vitamin D3 (VD3), vitamin E (VE), vitamin K3 (VK3), vitamin B1 (VB1), vitamin B2 (VB2), vitamin B3 (VB3), vitamin B5 (VB5), and vitamin B6 (VB6) in vitamin premixes and VTM premixes during storage was determined. The stability of vitamins in vitamin premixes and VTM premixes was determined and reported as the residual vitamin activity (% of initial) at each sampling point. Results: The effect of choline on VK3 retention was significant in vitamin premixes (p<0.05). The negative effect of storage time was significant for the retentions of VD3, VK3, VB1, VB2, VB5, and VB6 in vitamin premix (p<0.05). For VTM premixes, negative effect of storage time was significant (p<0.05) for the losses of vitamin in VTM premixes. Choline and high concentrations of Cu and Zn significantly increased VA, VK3, VB1, and VB2 loss during storage (p<0.05). The supplementation of high concentrations of Cu and Zn significantly decreased the concentrations of VD3 and VB6 (p<0.05) in VTM premixes at extended storage time. Conclusion: The maximum vitamin stability was detected in vitamin and VTM premixes containing no choline or excess Cu and Zn. The results indicated that extended storage time increased degradation of vitamin in vitamin or VTM premixes. These results may provide useful information for vitamin and VTM premixes to improve the knowledge of vitamin in terms of its stability. Objective: The present work was undertaken to evaluate the effects of storage time, choline chloride, and high concentrations of Cu and Zn on the kinetic behavior of vitamin degradation during storage in two vitamin premixes and four vitamin-trace mineral (VTM) premixes.Methods: Two vitamin premixes (with or without 160,000 mg/kg of choline) were stored at 25°C and 60% humidity. Besides, four VTM premixes were used to evaluate the effects of choline (0 vs 40,000 mg/kg) and trace minerals (low CuSO₄+ZnO vs high CuSO₄+ZnO) on vitamin stability in VTM premixes stored in room, and the VTM premixes were stored in room temperature at 22°C. Subsamples from each vitamin and VTM premix were collected at 0, 1, 2, 3, 6, and 12 months. The retention of vitamin A (VA), vitamin D₃ (VD₃), vitamin E (VE), vitamin K₃ (VK₃), vitamin B₁ (VB₁), vitamin B₂ (VB₂), vitamin B₃ (VB₃), vitamin B₅ (VB₅), and vitamin B₆ (VB₆) in vitamin premixes and VTM premixes during storage was determined. The stability of vitamins in vitamin premixes and VTM premixes was determined and reported as the residual vitamin activity (% of initial) at each sampling point.Results: The effect of choline on VK₃ retention was significant in vitamin premixes (p<0.05). The negative effect of storage time was significant for the retentions of VD₃, VK₃, VB₁, VB₂, VB₅, and VB₆ in vitamin premix (p<0.05). For VTM premixes, negative effect of storage time was significant (p<0.05) for the losses of vitamin in VTM premixes. Choline and high concentrations of Cu and Zn significantly increased VA, VK₃, VB₁, and VB₂ loss during storage (p<0.05). The supplementation of high concentrations of Cu and Zn significantly decreased the concentrations of VD₃ and VB₆ (p<0.05) in VTM premixes at extended storage time.Conclusion: The maximum vitamin stability was detected in vitamin and VTM premixes containing no choline or excess Cu and Zn. The results indicated that extended storage time increased degradation of vitamin in vitamin or VTM premixes. These results may provide useful information for vitamin and VTM premixes to improve the knowledge of vitamin in terms of its stability.

The strategies for the supplementation of vitamins and trace minerals in pig production: surveying major producers in China

Yang, Pan,Wang, Hua Kai,Li, Long Xian,Ma, Yong Xi Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.8

Objective: Adequate vitamin and trace mineral intake for pigs are important to achieve satisfactory growth performance. There are no data available on the vitamin and trace mineral intake across pig producers in China. The purpose of this study was to investigate and describe the amount of vitamin and trace minerals used in Chinese pig diets. Methods: A 1-year survey of supplemented vitamin and trace minerals in pig diets was organized in China. A total of 69 producers were invited for the survey, which represents approximately 90% of the pig herd in China. Data were compiled by bodyweight stages to determine descriptive statistics. Nutrients were evaluated for vitamin A, vitamin D, vitamin E, vitamin K, thiamine, riboflavin, vitamin B₆, vitamin B₁₂, pantothenic acid, niacin, folic acid, biotin, choline, copper, iron, manganese, zinc, selenium, and iodine. Data were statistically analyzed by functions in Excel. Results: The results indicated variation for supplemented vitamin (vitamin A, vitamin D, vitamin E, vitamin K, vitamin B₁₂, pantothenic acid, niacin, and choline) and trace minerals (copper, manganese, zinc, and iodine) in pig diets, but most vitamins and trace minerals were included at concentrations far above the total dietary requirement estimates reported by the National Research Council and the China's Feeding Standard of Swine. Conclusion: The levels of vitamin and trace mineral used in China's pig industry vary widely. Adding a high concentration for vitamin and trace mineral appears to be common practice in pig diets. This investigation provides a reference for supplementation rates of the vitamins and trace minerals in the China's pig industry.