Experimental Study on Synchronous Shifting for AMT without Synchronizer Based on Three-phase Induction Motor

Yunxia LI,Zengcai WANG,Weili PENG,Zhou ZHENG 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.2

In order to reduce shifting jerks, synchronous shift is needed on transmission with gear ratios. How to achieve synchronous shift has been the difficulty of AMT (Automated Mechanical Transmission) without synchronizer, which is the main emphasis of shift schedule. In this paper, the experimental study on synchronous up-shifting and down-shifting is given by test-bed which consisted of three-phase induction motor and heavy-duty AMT without synchronizer. Based on shift model, the synchronous speed difference is put forward for the synchronous shift strategy. The synchronizing control strategy of up-shifting is proposed on the basis of the braking characteristics of TB (transmission brake). The synchronizing control strategy of down-shifting is given according to the characteristics of the three-phase induction motor. Under the conditions of various synchronous speed differences, the up-shifting experiments and down-shifting experiments are achieved. By comparisons, the best value of synchronous speed difference is discussed in terms of gear-position and working conditions. The results of shifting experiments show that the synchronous shifting strategies for AMT without synchronizer based on three-phase induction can decrease shifting jerks and improve shift qualities.

Constant Acceleration Control for AMT’s Application in Belt Conveyor’s Soft Starting

Yunxia Li,Zengcai Wang,Xiaoyan Cong 보안공학연구지원센터 2013 International Journal of Control and Automation Vol.6 No.6

Shift Process Analysis of AMT without Synchronizer Based on Three-phase Induction Motor

Yunxia Li,Zengcai Wang,Xiaoyan Cong 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.6

Testicular Characteristics and the Block to Spermatogenesis in Mature Hinny

Han, Hongmei,Wang, Aihong,Liu, Liming,Zhao, Gaoping,Su, Jie,Wang, Biao,Li, Yunxia,Zhang, Jindun,Wu, Baojiang,Sun, Wei,Hu, Shuxiang,Li, Shuyu,Zhao, Lixia,Li, Xihe Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.6

Most hinnies (female donkey${\times}$male horse) and mules (female horse${\times}$male donkey) are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean number of seminiferous tubules was significantly higher in stallion and hinny than Jack donkey (p<0.01), the mean proportion of seminiferous tubules was lower in the hinny (p<0.01) which resulted in a smaller diameter of seminiferous tubules. The mean number of spermatogonia and spermatocytes per unit area were significantly lower in hinny testis (p<0.01) and no spermatids or mature spermatozoa cells were found during immunofluorescent analyses. These results indicated that defects in seminiferous tubule development and structure occur in the testis of hinnies. Furthermore, most spermatogonia and spermatocytes cease development in synapsis during mid-meiosis of spermatocytes, which results in a block to spermatogenesis that prevents the formation of spermatids and matured spermatozoa during meiosis in male hinnies.

Correlation between in vitro fertilization and artificial insemination in Holstein bulls

Sun Wei,Li Yunxia,Su Jie,Bao Xiangnan,Ding Rui,Zhao Gaoping,Cao Guifang,Hu Shuxiang,Wang Jianguo,Sun Qingyuan,Yu Haiquan,Li Xihe 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.12

Objective: Owing to the lack of a breeding index for efficient and quick fertility evaluations of Holstein bulls when using traditional or genome-wide detection methods, this study aimed to determine whether in vitro fertilization (IVF) could be used as an indicator of conception rate of artificial insemination (AI).Methods: Conventional and sexed frozen semen from nine bulls were used for IVF and AI.Results: The IVF and AI conception rates of each bull were confirmed to be positively correlated between the conventional frozen and sexed frozen semen. The correlation coefficient R values of nine bulls between IVF and AI methods were 0.73 and 0.97 for the conventional frozen and sexed frozen semen, respectively. The average conception rate of three bulls undergoing AI was 69.5% and 64.2%, 61.8% and 58.8%, and 48.2% and 46.2% in first-, second-, and third-born cows when conventional frozen and sexed frozen semen were used, respectively, which showed a positive correlation with the fertilization rate in the same parity. We propose an evaluation standard to assess the fertilization ability of bulls based on their IVF test results, which is categorized into three grades: grade one, normal fertility bull with an AI conception rate of 40%±5% and IVF rate of 45% to 60%; grade two, higher fertility bull with an AI conception rate of 50%±5% and IVF rate of 61% to 80%; and grade three, highest fertility bull with an AI conception rate of 60%±5% and IVF rate of >80%.Conclusion: These findings reveal that IVF results can be used as a breeding index for bulls to evaluate their AI conception ability, which may shorten the time required to select bulls for breeding. Objective: Owing to the lack of a breeding index for efficient and quick fertility evaluations of Holstein bulls when using traditional or genome-wide detection methods, this study aimed to determine whether in vitro fertilization (IVF) could be used as an indicator of conception rate of artificial insemination (AI). Methods: Conventional and sexed frozen semen from nine bulls were used for IVF and AI. Results: The IVF and AI conception rates of each bull were confirmed to be positively correlated between the conventional frozen and sexed frozen semen. The correlation coefficient R values of nine bulls between IVF and AI methods were 0.73 and 0.97 for the conventional frozen and sexed frozen semen, respectively. The average conception rate of three bulls undergoing AI was 69.5% and 64.2%, 61.8% and 58.8%, and 48.2% and 46.2% in first-, second-, and third-born cows when conventional frozen and sexed frozen semen were used, respectively, which showed a positive correlation with the fertilization rate in the same parity. We propose an evaluation standard to assess the fertilization ability of bulls based on their IVF test results, which is categorized into three grades: grade one, normal fertility bull with an AI conception rate of 40%±5% and IVF rate of 45% to 60%; grade two, higher fertility bull with an AI conception rate of 50%±5% and IVF rate of 61% to 80%; and grade three, highest fertility bull with an AI conception rate of 60%±5% and IVF rate of >80%. Conclusion: These findings reveal that IVF results can be used as a breeding index for bulls to evaluate their AI conception ability, which may shorten the time required to select bulls for breeding.

Distal pancreatectomy with splenectomy for the management of splenic hilum metastasis in cytoreductive surgery of epithelial ovarian cancer

Libing Xiang,Yunxia Tu,Tiancong He,Xuxia Shen,Ziting Li,Xiaohua Wu,Huijuan Yang 대한부인종양학회 2016 Journal of Gynecologic Oncology Vol.27 No.6

Objective: Distal pancreatectomy with splenectomy may be required for optimalcytoreductive surgery in patients with epithelial ovarian cancer (EOC) metastasized tosplenic hilum. This study evaluates the morbidity and treatment outcomes of the uncommonprocedure in the management of advanced or recurrent EOC. Methods: This study recruited 18 patients who underwent distal pancreatectomy withsplenectomy during cytoreductive surgery of EOC. Their clinicopathological characteristicsand follow-up data were retrospectively analyzed. Results: All tumors were confirmed as high-grade serous carcinomas. The mediandiameter of metastatic tumors located in splenic hilum was 3.5 cm (range, 1 to 10 cm). Optimal cytoreduction was achieved in all patients. Eight patients (44.4%) sufferedfrom postoperative complications. The morbidity associated with distal pancreatectomyand splenectomy included pancreatic leakage (22.2%), encapsulated effusion in theleft upper quadrant (11.1%), intra-abdominal infection (11.1%), pleural effusion withor without pulmonary atelectasis (11.1%), intestinal obstruction (5.6%), pneumonia(5.6%), postoperative hemorrhage (5.6%), and pancreatic pseudocyst (5.6%). Therewas no perioperative mortality. The majority of complications were treated successfullywith conservative management. During the median follow-up duration of 25 months,nine patients experienced recurrence, and three patients died of the disease. The 2-yearprogression-free survival and overall survival were 40.2% and 84.8%, respectively. Conclusion: The inclusion of distal pancreatectomy with splenectomy as part ofcytoreduction for the management of ovarian cancer was associated with high morbidity;however, the majority of complications could be managed with conservative therapy.

Robust Controller Design for Uncertain Linear Systems with Finite-frequency Specifications: A Polynomially Parameter-dependent Approach

Yingying Ren,Qing Li,Da-Wei Ding,Wen Kang,Yunxia Xia 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.11

This paper investigates the robust controller design for polytopic-type uncertain linear systems disturbed by external disturbances in restricted frequency ranges. The primary goal is to design a state-feedback controller, ensuring that the closed-loop system is robustly stable and keeps a prescribed finite-frequency (FF) disturbanceattenuation performance. For this purpose, a robust generalized Kalman-Yakubovich-Popov (KYP) lemma is applied to describe the finite-frequency specification, aiming at improving the disturbance-attenuation performance over the given frequency range. In this setting, more relaxed analysis conditions for robust stability and finitefrequency specifications are derived by introducing additional slack variables, which contain some existing conditions as special cases. Based on the homogeneous polynomially parameter-dependent (HPPD) technique, new controller design conditions in terms of linear matrix inequalities (LMIs) are developed. It is shown that the proposed finite-frequency design scheme can achieve a better disturbance- suppression performance in restricted frequency ranges than the existing ones, which is illustrated by an example about the satellite system.

Energetic walking gaits studied by a simple actuated inverted pendulum model

Kang An,Yingyuan Liu,Yiran Li,Yunxia Zhang,Chengju Liu 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.5

The mechanical structure and the joint torques configuration are the important parts in the biped robot design. Meanwhile, different walking speed and step length should be chosen to achieve efficient gait according to different need of walking environment. Therefore, this paper investigates the energetic walking gaits using a simple actuated inverted pendulum model. Joint torques and push-off impulse are both added in the model. The walking gaits with different joint torques configuration and with different combination of walking speeds and step lengths are analyzed. The results show that hip velocity direction is changed by the push-off impulse just before the heelstrike, which reduces the energy consumption of each step. The walking gait with minimal energy consumption is the walking pattern only with push-off, the energy cost of which is 1/4 of the walking pattern only with joint torque during the swing phase. The cost of transport (COT) and the push-off impulse of the walking gait is increasing with the increase of walking speed and step length. Using same value of push-off impulse, the walking with long step length and slow speed is more efficient. The paper can provide suggestions for designing advanced legged robot systems with high energy efficiency and various gaits. For example, the consideration of push-off mechanism can be used in the biped robots design.

GLOBAL CHARACTERISTICS ANALYSIS FOR VEHICLE SYSTEM WITH DRIVING TORQUE BASED ON DISSIPATION OF ENERGY

Fanyu Meng,Shuming Shi,Boshi Zhang,Yunxia Li,Nan Lin 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.6

As more and more researchers begin to analyse the dynamics characteristics of high-degree-of-freedom and nonlinear vehicle models, it is very important and valuable to propose a new analysis method for this type of model. Moreover, it is a promising research direction to propose quantitative indicators for analysing global vehicle dynamics. Therefore, on the basis of classic works, this paper proposes and verifies a quantitative analysis method - dissipation of energy method for 5-DOF nonlinear vehicle plane motion model for the first time. The quantitative indicators for vehicle nonlinear dynamics is expanded. The transfer relationship between the energy components is revealed, which shows that the dissipation of energy method can reflect the dynamics characteristics and stable region characteristics of the nonlinear 5-DOF vehicle system. The effects of tire force lateral-longitudinal coupling and driving modes on global dynamics are analysed. Finally, the prospect of this method is discussed.

Preparation of the Water-Soluble Fluorene-Containing Fluorescent Polymer by One-Pot Method

Yuan Wang,Hongchi Zhao,Haijian Tan,Xiaomeng Li,Yunxia Qian,Libin Bai,Yonggang Wu,Shufang Lv 한국고분자학회 2015 Macromolecular Research Vol.23 No.10

A water-soluble fluorescent polymer, 2,7-di{4'-[3''-(S-poly(acryloyl ethylene diamine hydrochloride)-2'''- methyl propionic acid)propionyloxy hexyloxy]phenyl}-9,9-di(n-octyl)fluorene (P3) with regular and ordered structure, was designed and synthesized with high conversion using click reaction between thiols and carbon-carbon double bonds. Because the S-H bond is relatively weak, thiol groups are subject to rapid oxidation during purification and storage and thereby result in the low conversion in the following click reaction. To circumvent this limitation, the synthesis of thiol groups and click reaction were simultaneously performed in one system (one-pot method). The intermediate products P1 (S-1-dodecyl-S'-[poly(N-Boc-acryloyl ethylene diamine)-2'-methyl propionic acid]trithiocarbonate) and M2 (2,7-di[4-(acryloyloxy hexyloxy)phenyl]-9,9-di(n-octyl)fluorene) were prepared via reversible addition fragmentation chain transfer (RAFT) polymerization and Williamson synthesis, respectively. Then, 2,7- di{4'-[3''-(S-poly(N-Boc-acryloyl ethylene diamine)-2'''-methyl propionic acid)propionyloxy hexyloxy]phenyl}- 9,9-di(n-octyl)fluorene (P2) was synthesized with high conversion (83%) by employing a click reaction with P1 and M2 as starting materials. Finally, water-soluble fluorescent polymer P3 was obtained after the deprotection of P2. M2, P1, P2 and P3 were characterized by Fourier transform infrared (FTIR) spectrum, nuclear magnetic resonance (NMR), high-resolution mass spectroscopy (MS), gel permeation chromatograph (GPC), UV-Visible (UV-Vis) spectrum, and fluorescence, respectively. The results revealed that P3 displayed good solubility in water and not only exhibited a blue fluorescence emission band in water but also had a similar photoluminescent spectra to those of M2 and P2 in dichloromethane. The fluorescence quantum yield of P3 in aqueous solution could reach 0.10. In addition, the result of cell cytotoxicity indicates that P3 has low cytotoxicity and exhibits potential for biomedical applications. This work provides a new insight into the study of water-soluble fluorescent polymer.