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    Physical Characterization of Ionic Liquid-Modified Polyvinyl Alcohol and Sodium Thiocyanate Polymer Electrolytes for Electrochemical Double-Layer Capacitor Application
    AZEMTSOP Manfo Theodore , MEHRA Ram Mohan , KUMAR Yogesh , GUPTA Meenal
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 161-171.   DOI: 10.1007/s12204-021-2397-y
    Abstract336)      PDF (1140KB)(112)      
    Novel gel polymer electrolytes (GPEs) composed of polyvinyl alcohol (PVA) and sodium thiocyanate were developed via a solution casting technique. An ionic liquid (IL), 1-ethyl-3-methyl-imidazolium tricyanomethanide ([EMIM][TCM]), was doped into a polymer–salt complex system (PVA + NaSCN) to further enhance the conductivity. IL-doped polymer electrolyte (ILDPE) films were characterized using X-ray diffraction (XRD), polarized optical microscopy (POM), Fourier-transform infrared (FTIR) spectroscopy, and conductivity measurements. XRD was performed to check the degree of crystallinity and amorphicity of the ILDPE films, and the amorphicity of GPEs increased with the increase of the IL content. POM was employed to evaluate the changes in the surface morphology due to the inclusion of salt and IL in the PVA. The compositional nature of the GPE films was examined via FTIR studies. The electrical and electrochemical properties were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The maximum conductivity for the GPE film was estimated to be 1.10 × 10-5 S/cm for 6% (mass fraction) of IL in the polymer–salt complex. The ionic transference number was approximately 0.97. An electrochemical double-layer capacitor (EDLC) was built from optimized GPE films and reduced graphene oxide-based electrodes. The specific capacitance calculated from the cyclic voltammograms of the EDLC cells was 3 F/g.
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    Integrated Hydraulic-Driven Wearable Robot for Knee Assistance
    ZHAO Yafei (赵亚飞), HUANG Chaoyi (黄超逸), ZOU Yuging(邹玉莹), ZOUKehan(邹可涵), zoU Xiaogang(邹笑阳), XUE .Jiaqi(薛嘉琦), LI Xiaoting(李晓婷), KOH Keng Huat, WANG Xiaojun(王小军), LAI Wai Chiu King(赖伟超), HU Yong(胡勇), XI Ning(席宁), WANG Zheng(王峥)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 289-295.   DOI: 10.1007/s12204-023-2602-2
    Abstract326)      PDF (1156KB)(138)      
    Age-related diseases can lead to knee joint misfunction, making knee assistance necessary through the use of robotic wearable braces. However, existing wearable robots face challenges in force transmission and human motion adaptation, particularly among the elderly. Although soft actuators have been used in wearable robots, achieving rapid response and motion control while maintaining portability remains challenging. To address these issues, we propose a soft-robotic knee brace system integrated with multiple sensors and a direct-drive hydraulic actuation system. This approach allows for controlled and rapid force output on the portable hydraulic system. The multi-sensor feedback structure enables the robotic system to collaborate with the human body through human physiological signal and body motion information. The human user tests demonstrate that the knee robot provides assistive torques to the knee joint by being triggered by the electromyography signal and under human motion control.
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    Strength-Toughness Improvement of 15-5PH Stainless Steel by Double Aging Treatment
    TE Rigele (特日格乐), ZHANG Yutuo, ∗ (张玉妥)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 270-279.   DOI: 10.1007/s12204-021-2390-5
    Abstract323)      PDF (3166KB)(64)      
    To obtain better strength-toughness balance of 15-5PH stainless steel, a double aging treatment is proposed to investigate the mechanical properties and microstructure evolution. In this study, Cu precipitates and reversed austenite played a determining role to improve strength-toughness combination. The microstructure was observed using electron backscattered diffraction, transmission electron microscopy and scanning transmission electron microscopy. The volume fractions of Cu precipitates and reversed austenite were calculated with Thermo-Calc software and measured by X-ray diffraction. The results showed that the reversed austenite is formed at the martensitic lath boundaries and its volume fraction also increases with the increase of the aging temperature. At the same time, the size of the Cu precipitates gradually increases. Compared with the traditional single aging and double aging treatment, double aging treatment of 15-5PH stainless steel can increase the toughness while retaining the necessary strength. During double aging of 550 ℃ × 4 h + 580 ℃ × 1 h, 15-5PH stainless steel has the best strength and low-temperature (- 40 ℃) toughness match. Its yield strength, ultimate tensile strength and the Charpy impact energy are 1.037 GPa, 1.086 GPa and 179 J, respectively.
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    Design of Twin-Screw Compressor Rotor Tooth Profile with Meshing Clearance Based on Graphic Method and Alpha Shape Algorithm
    YANG Jian, ∗ (杨 剑), XU Mingzhao (徐明照), LU Zheng (陆 征)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 243-254.   DOI: 10.1007/s12204-021-2396-z
    Abstract261)      PDF (1955KB)(45)      
    Rotor clearance is necessary for the safe operation of twin-screw compressors, and it has a major impact on the performance of twin-screw compressors. The purpose of this study was to obtain a rotor tooth profile with reasonable meshing clearance on the rotor end surface, so that the clearance on the rotor contact line would be uniform and the rotor could be smoothly meshed. Under ideal conditions, the rotor of a screw compressor should have no clearance or interference. However, owing to assembly errors, thermal compression, stress deformation, and other factors, a rotor without backlash modification will inevitably produce interference during operation. A new design method based on the Alpha shape solution was proposed to achieve an efficient and high-precision design of the clearance of the twin-screw rotor profile. This method avoids the complex analytical calculations in the traditional envelope principle. The best approximation of the points on the rotor conjugate motion sweeping surface in the points is illuminated using a specific color. The sweeping surface of the screw rotor single-tooth profile is roughly scanned to capture the base point set of the sweeping surface boundary points. The chord length and tilt angle of each interval are calculated using the value of the base point set to adjust the position, phase, and magnification of each interval sweeping surface. Finally, the data point set is converted to the same coordinate system to generate the conjugated rotor profile. An example was used to verify the feasibility and adaptability of this method. Based on the equidistant profile method, the clearance between male and female rotors of a screw compressor was obtained under actual operation conditions. Therefore, this study provides a basis for the meshing clearance design in the machining of twin-screw compressor rotors.
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    Mechanical Analysis Methods of Cantilever Gearbox Housing
    WANG Jue∗ (王 珏), LI Peng (李 朋), SONG Shiyao (宋诗瑶)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 233-242.   DOI: 10.1007/s12204-021-2316-2
    Abstract259)      PDF (2037KB)(38)      
    The mechanical state of cantilever gearbox housing is different from ordinary ones due to the long arm of force caused by cantilever structure. Conventional mechanical analysis methods either took cantilever gearbox housing as ordinary ones or cantilever beam. Few published papers have specially focused on mechanical analysis method for cantilever gearbox housing. This paper takes a longwall shearer cutting unit gearbox (SCUG) as an example and the mechanical analysis method is investigated according to the causes of fatigue for SCUG. Force analysis model is established for finding out regions of static fatigue caused by low-frequency loads, and local resonance analysis is used for finding out regions of vibration fatigue caused by high-frequency loads. Not only bending moment but also torque caused by gear meshing forces is taken into account in the force analysis model. Vibration response is obtained from cutting experiment, and dominant frequencies of local resonance are obtained by frequency domain analysis. Finite element model of SCUG is established, and natural frequencies and strain modes are analyzed for obtaining the main vibration modes corresponding to dominant frequencies. Hence, large stress regions caused by low and high frequency loads are obtained. Results show that the worst working condition is oblique cutting, and the stress of B-B in 600 mm cutting depth can reach 166 MPa. Obviously, 950 Hz, 1 250 Hz, and 1 400 Hz are dominant frequencies of SCUG (23rd, 25th and 27th natural frequencies). Generally, this paper proposes some principles for mechanical analysis method of cantilever gearbox housing.
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    Foreground Segmentation Network with Enhanced Attention
    JIANG Rui1*(姜﹐锐),ZHU Ruiriang1(朱瑞祥),CAI Xiaocui1(蔡萧萃),SU Hu2(苏虎)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 360-369.   DOI: 10.1007/s12204-023-2603-1
    Abstract234)      PDF (734KB)(34)      
    Moving object segmentation (MOS) is one of the essential functions of the vision system of all robots,including medical robots. Deep learning-based MOS methods, especially deep end-to-end MOS methods, are actively investigated in this field. Foreground segmentation networks (FgSegNets) are representative deep end-to-end MOS methods proposed recently. This study explores a new mechanism to improve the spatial feature learning capability of FgSegNets with relatively few brought parameters. Specifically, we propose an enhanced attention (EA) module, a parallel connection of an attention module and a lightweight enhancement module, with sequential attention and residual attention as special cases. We also propose integrating EA with FgSegNet v2 by taking the lightweight convolutional block attention module as the attention module and plugging EA module after the two Maxpooling layers of the encoder. The derived new model is named FgSegNet v2 EA. The ablation study verifies the effectiveness of the proposed EA module and integration strategy. The results on the CDnet2014 dataset, which depicts human activities and vehicles captured in different scenes, show that FgSegNet v2 EA outperforms FgSegNet v2 by 0.08% and 14.5% under the settings of scene dependent evaluation and scene independent evaluation, respectively, which indicates the positive effect of EA on improving spatial feature learning capability of FgSegNet v2.
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    Progress in Force-Sensing Techniques for Surgical Robots
    GAO Hongyan1,2(高红岩),AI Xiaojie1,2(艾孝杰),SUN Zhenglong3(孙正隆),CHEN Weidong1,2(陈卫东),GAO Anzhu1,2*(高安柱)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 370-381.   DOI: 10.1007/s12204-023-2607-x
    Abstract217)      PDF (1017KB)(70)      
    Force sensing is vital for situational awareness and safe interaction during minimally invasive surgery. Consequently, surgical robots with integrated force-sensing techniques ensure precise and safe operations. Over the past few decades, there has been considerable progress in force-sensing techniques for surgical robots. This review summarizes the existing electrically- and optically-based force sensors for surgical robots, including piezoresistive, piezoelectric, capacitive, intensity/phase-modulated, and fiber Bragg gratings. Their principles, applications, advantages, and limitations are also discussed. Finally, we summarize our conclusions regarding state-of-the-art force-sensing technologies for surgical robotics.
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    Synthesis and Characterization of Copper Doped Zinc Oxide Thin Films Deposited by RF/DC Sputtering Technique
    KHAN Mohibul, ALAM Md. Shabaz, AHMED Sk. Faruque∗
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 172-179.   DOI: 10.1007/s12204-022-2462-1
    Abstract216)      PDF (698KB)(52)      
    Undoped and copper (Cu) doped zinc oxide (Zn1-xCuxO, where x = 0—0.065) nano crystal thin films have been deposited on glass substrate via RF/DC reactive co-sputtering technique. The aim of this work is to investigate the crystal structure of ZnO and Cu doped ZnO thin films and also study the effect of Cu doping on optical band gap of ZnO thin films. The identification and confirmation of the crystallinity, film thickness and surface morphology of the nano range thin films are confirmed by using X-ray diffractometer (XRD), scanning electron microscope and atomic force microscope. The XRD peak at a diffractive angle of 34.44° and Miller indices at (002) confirms the ZnO thin films. Crystallite size of undoped ZnO thin films is 27 nm and decreases from 27 nm to 22 nm with increasing the atomic fraction of Cu (xCu) in the ZnO thin films from 0 to 6.5% respectively, which is calculated from XRD (002) peaks. The different bonding information of all deposited films was investigated by Fourier transform infrared spectrometer in the range of wave number between 400 cm-1 to 4 000 cm-1. Optical band gap energy of all deposited thin films was analyzed by ultraviolet visible spectrophotometer, which varies from 3.35 eV to 3.19 eV with the increase of xCu from 0 to 6.5% respectively. Urbach energy of the deposited thin films increases from 115 meV to 228 meV with the increase of xCu from 0 to 6.5% respectively.
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    Novel Concentric Tube Robot Based on Double-Threaded Helical Gear Tube
    CHEN Weichi(陈韦池), LIU Haocheng(刘浩城), LI Zijian(李子建), GUO Jing, (郭靖), ZHAI Zhenkun(翟振坤), MENG Wei(孟伟)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 296-306.   DOI: 10.1007/s12204-023-2595-x
    Abstract209)      PDF (2087KB)(61)      
    Nasopharyngeal carcinoma is a malignant tumor originating from the nasal mucosa. It is a malignant tumor of the head and neck. Concentric tube robot (CTR), as it can form a complicated shape and access hardto-reach lesions, is often used in minimally invasive surgeries. However, some CTRs are bulky because of their transmission design. In this paper, a light CTR based on double-threaded helical gear tube is proposed. Such a CTR is less cumbersome than the traditional CTR as its actuation unit is compact and miniaturized. The mapping relationship between the gear tube attitude and motor output angle is obtained by kinematic analysis. The precision, stability, and repeatability of the driving mechanism are tested. The experimental results show that the positioning error in the translation test is less than 0.3 mm, the rolling angle error in the stability test is less than 0.6?, and the error in the translation repeatability test is less than 0.005 mm. Finally, a tip-targeting test is performed using the new CTR, which verifies the feasibility of the CTR for surgeries.
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    Numerical Study on Separation of Circulating Tumor Cell Using Dielectrophoresis in a Four-Electrode Microfluidic Device
    WANG Yukuna (王雨坤), DING Xiantingb (丁显廷), ZHANG Zhinana (张执南)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 391-.   DOI: 10.1007/s12204-022-2459-9
    Abstract206)      PDF (1462KB)(214)      
    This numerical study proposes a cell sorting technique based on dielectrophoresis (DEP) in a microfluidic chip. Under the joint effect of DEP and fluid drag, white blood cells and circulating tumor cells are separated because of different dielectric properties. First, the mathematical models of device geometry, single cell, DEP force, electric field, and flow field are established to simulate the cell motion. Based on the simulation model, important boundary parameters are discussed to optimize the cell sorting ability of the device. A proper matching relationship between voltage and flow rate is then provided. The inlet and outlet conditions are also investigated to control the particle motion in the flow field. The significance of this study is to verify the cell separating ability of the microfluidic chip, and to provide a logistic design for the separation of rare diseased cells.
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    Band Structure Characteristics of Two-Dimensional Si-A (Ge, Pb, Sn) Alloy-Air Holes Thermal Crystals
    AZKA Umar ∗, JIANG Chun (姜 淳), KHUSHIK Muhammad Hanif Ahmed Khan
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 180-185.   DOI: 10.1007/s12204-022-2485-7
    Abstract184)      PDF (539KB)(39)      
    This paper designs the thermal crystals composed of alloy materials with air holes and analyzes their properties of band structures, heat transmission, and flux spectra. Thermal crystals composed of Si-A (A=Ge, Sn, Pb) alloys as background materials and air holes with square array are used to construct an elastic-constant periodic structure and their high-frequency phononic band is calculated by deploying finite element methods. Moreover, this paper investigates heat transmission through a finite array of thermally excited phonons and presents the thermal crystal with maximum heat transport. The results show that a wider bandgap could be achieved by increasing the air hole radius and decreasing the lattice constant. In the alloy materials, with increasing atomic radius and thus atomic mass (Ge, Sn, Pb), the frequency range (contributed to thermal conductivity) shifts towards lower frequency. Hence, the bandgap frequencies also shift toward low frequency, but this decreasing rate is not constant or in order, so former may have a faster or slower decreasing rate than the later. Thus, the frequency range for the contribution of heat transportation overlaps with the bandgap frequency range. The development of thermal crystals is promising for managing heat and controlling the propagation of the thermal wave.
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    Shape Sensing for Single-Port Continuum Surgical Robot Using Few Multicore Fiber Bragg Grating Sensors
    LI Dingjia1,2,3,4(黎定佳),WANG Chongang1,2,3(王重阳),GUO Wei5(郭伟),WANG Zhidong6(王志东),ZHANG Zhongtao5(张忠涛),LIU Hao1,2,3*(刘浩)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 312-322.   DOI: 10.1007/s12204-023-2579-x
    Abstract181)      PDF (2606KB)(34)      
    We proposed a method for shape sensing using a few multicore fiber Bragg grating (FBG) sensors in a single-port continuum surgical robot (CSR). The traditional method of utilizing a forward kinematic model to calculate the shape of a single-port CSR is limited by the accuracy of the model. If FBG sensors are used for shape sensing, their accuracy will be affected by their number, especially in long and flexible CSRs. A fusion method based on an extended Kalman filter (EKF) was proposed to solve this problem. Shape reconstruction was performed using the CSR forward kinematic model and FBG sensors, and the two results were fused using an EKF. The CSR reconstruction method adopted the incremental form of the forward kinematic model, while the FBG sensor method adopted the discrete arc-segment assumption method. The fusion method can eliminate the inaccuracy of the kinematic model and obtain more accurate shape reconstruction results using only a small number of FBG sensors. We validated our algorithm through experiments on multiple bending shapes under different load conditions. The results show that our method significantly outperformed the traditional methods in terms of robustness and effectiveness.
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    Influence of Forming Pressure on Properties of Yttrium Iron Garnet Ferrite
    CHEN Zhigang (陈志刚), LI Haihua∗ (李海华)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 207-212.   DOI: 10.1007/s12204-022-2478-6
    Abstract167)      PDF (589KB)(28)      
    The Ca-Sn co-substituted yttrium iron garnet (YIG) ferrite materials were prepared by the traditional oxide solid-state reaction method, and the influence of forming pressure on the density, morphology and magnetic properties of YIG ferrite was systematically studied. The results show that the density of YIG ferrite green body increases with the increase of the forming pressure, while the density of its sintered body shows a trend of first increasing and then decreasing. At the same time, the ferromagnetic resonance (FMR) linewidth of YIG sample first decreases and then increases. Meanwhile, the effects of forming pressure on the saturation magnetization, remanence and coercivity of the sample can be ignored. This study proves that the density and FMR linewidth of YIG materials can be controlled by regulating the forming pressure and the best performance is obtained for the sample prepared under a forming pressure of 5 MPa.
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    In-Plane Elastic Properties of Stitched Plain Weave Composite Laminate
    YUAN Lihua (袁丽华), LIANG Sen∗ (梁 森), YAN Shengyu (闫盛宇)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 220-232.   DOI: 10.1007/s12204-021-2375-4
    Abstract166)      PDF (1646KB)(38)      
    A representative volume element method and a novel mesomechanical-based polyline model are proposed to describe the misalignment of in-plane fibers induced by the insertion of stitch thread. A multi-scale mathematical model of in-plane elastic parameters for stitched composite laminate is established with ply-angle and stitch parameters as well as material parameters taken into account. Based on the fabrication of specimens and the verification of experimental platform, the superposition influences of stitch on structural anisotropy are revealed by the developed theoretical model. Results indicate that the stitch orientation can increase the structural anisotropy. The decreases of stitch pitch and spacing as well as the increase of thread diameter obviously reduce the elastic and shear moduli of laminates. Furthermore, the elastic and shear moduli as well as Poisson’s ratios show sinusoidal changes with a period of 90° as the ply-angle increases. The theoretical model not only analyzes the in-plane mechanical properties of stitched laminate with ply-angle, but also lays a foundation for the dynamic studies of stitched sandwich structures with ribs in the future.
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    Visual Positioning of Nasal Swab Robot Based on Hierarchical Decision
    LI Guozhia a(李国志),ZOU Shuizhong b*(邹水中),DING Shuacue a(丁数学)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 323-329.   DOI: 10.1007/s12204-023-2581-3
    Abstract164)      PDF (743KB)(36)      
    This study focuses on a robot vision localization method for coping with the operational task of automatic nasal swab sampling. The application is important in the detection and epidemic prevention of Corona Virus Disease 2019 (COVID-19) to alleviate the large-scale negative impact of individuals suffering from pneumonia owing to COVID-19. In this method, the idea of a hierarchical decision network is used to consider the strong infectious characteristics of the COVID-19, which is followed by processing the robot behavior constraint condition. The visual navigation and positioning method using a single-arm robot for sampling is also planned, which considers the operation characteristics of medical staff. In the decision network, the risk factor for potential contact infection caused by swab sampling operations is established to avoid the spread among personnel. A robot visual servo control with artificial intelligence characteristics is developed to achieve a stable and safe nasal swab sampling operation. Experiments demonstrate that the proposed method can achieve good vision positioning for the robots and provide technical support for managing new major public health situations.
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    Numerical Simulation on the Effect of Conveyor Velocity of the Roller Table on Stress Distribution and Evolution in Large Aluminum Alloy Thick Plates
    ZHU Kai, (祝 楷), XIONG Baiqing, ∗ (熊柏青), YAN Hongwei, (闫宏伟), ZHANG Yongan, (张永安), LI Zhihui, (李志辉), LI Xiwu, (李锡武), LIU Hongwei, (刘红伟), WEN Kai, (温 凯), YAN Lizhen, (闫丽珍)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 255-263.   DOI: 10.1007/s12204-021-2389-y
    Abstract157)      PDF (1596KB)(31)      
    Solution heat treatment combined with a rapid quenching operation, which can effectively suppress the decomposition of the supersaturated solid solution in the matrix, is a vital process step for producing large precipitation-hardenable aluminum alloy thick plates with desired properties. However, large thermal gradients that result from the non-uniform cooling rates during quenching usually give rise to severely heterogeneous distributions of residual stress in thick plates. The presence of roller-hearth furnaces makes it possible to achieve continuous and integral solution-quenching treatment for large aluminum alloy thick plates. The conveyor velocity of the roller table in the roller-hearth furnace is a key parameter but its influence is less addressed in literature. Thus, in the present work, finite element thermal-mechanical simulations taking into account different conveyor velocities of the roller table were employed to predict the temperature variations and residual stress distributions in large aluminum alloy thick plates during quenching process. Four different velocities were utilized in the simulations. The modeling results showed that the temperature evolutions as well as the distributions of the induced internal stresses in those large thick plates during quenching treatments were indeed affected by the conveyor velocities. Slower velocities were demonstrated to be favorable for gaining thick plates being with relatively homogeneous residual stress distributions in the plates.
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    Input-Constrained Hybrid Control of a Hyper-Redundant Mobile Medical Manipulator
    ZHANG Kaibo1(张凯波),CHEN Li1*(陈丽),DONG Qi2(董琦)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 348-359.   DOI: 10.1007/s12204-023-2580-4
    Abstract154)      PDF (909KB)(24)      
    To reduce the risk of infection in medical personnel working in infectious-disease areas, we proposed a hyper-redundant mobile medical manipulator (HRMMM) to perform contact tasks in place of healthcare workers. A kinematics-based tracking algorithm was designed to obtain highly accurate pose tracking. A kinematic model of the HRMMM was established and its global Jacobian matrix was deduced. An expression of the tracking error based on the Rodrigues rotation formula was designed, and the relationship between tracking errors and gripper velocities was derived to ensure accurate object tracking. Considering the input constraints of the physical system, a joint-constraint model of the HRMMM was established, and the variable-substitution method was used to transform asymmetric constraints to symmetric constraints. All constraints were normalized by dividing by their maximum values. A hybrid controller based on pseudo-inverse (PI) and quadratic programming (QP) was designed to satisfy the real-time motion-control requirements in medical events. The PI method was used when there was no input saturation, and the QP method was used when saturation occurred. A quadratic performance index was designed to ensure smooth switching between PI and QP. The simulation results showed that the HRMMM could approach the target pose with a smooth motion trajectory, while meeting different types of input constraints.
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    Effect of Fast Multiple Rotation Rolling on Microstructure and Properties of Ti6Al4V Alloy
    YANG Xiaojie, (杨晓洁), CHANG Xueting∗ (常雪婷), FAN Runhua (范润华)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 264-269.   DOI: 10.1007/s12204-021-2395-0
    Abstract151)      PDF (1470KB)(33)      
    Using fast multiple rotation rolling (FMRR), a nanostructure layer was fabricated on the surface of Ti6Al4V alloy. The microstructure of the surface layer was investigated using optical microscopy, transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. The results indicated that a nanostructured layer, with an average grain size of 72—83 nm, was obtained in the top surface layer, when the FMRR duration was 15 min. And the average grain size further reduced to 24—37 nm when the treatment duration increased to 45 min. High density dislocations, twins, and stacking faults were observed in the top surface layer. The microhardness of FMRR specimen, compared with original specimen, was significantly increased. A uniform, continuous and thicker compound layer was obtained in the top surface of FMRR sample, and the diffusion speed of N atom in the top surface layer was accelerated. FMRR treatment provides corrosion improvement.
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    Low Voltage Indium-Oxide-Zinc Thin Film Transistor Gated by KH550 Solid Electrolyte
    DONG Qian (董 钱), GUO Liqiang(郭立强), WANG Weilin (王伟琳), CHENG Guanggui (程广贵)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 186-191.   DOI: 10.1007/s12204-022-2421-x
    Abstract151)      PDF (763KB)(55)      
    With the development of integrate circuit and artificial intelligence, many kinds of transistors have been invented. In recent years, wide attention has been paid to the oxide thin film transistors due to its ease preparation, low cost, and suitability for mass production. Traditionally used gate dielectric film (such as silicon dioxide film) in oxide thin film transistor owns low dielectric constant, which leads to weak capacitive coupling between the gate dielectric layer and the channel layer. As a result, high voltage (10 V or more) needs to be applied on the gate electrode in order to achieve the purpose of regulating the current of channel layer. Therefore, new oxide thin film needs to be developed. In this work, silane coupling agents (3-triethoxysilypropyla-mine) KH550 solid electrolyte film was obtained by spin coating-process. The KH550 solid electrolyte was used as gate dielectric layer to fabricate low-voltage indium zinc oxide thin film transistor. The surface topography and thickness of KH550 solid electrolyte film were characterized by atomic force microscope and field emission scanning electron microscope, respectively. The capacitance-frequency curve of the sample was measured by impedance analyzer (Soloartron 1260A), and the electrical characteristics of the sample were analyzed by a semiconductor parameter analyzer (Keithley 4200 SCS). A maximum specific capacitance of about 7.3 μF/cm2 is obtained at 1 Hz. The transistor shows a good stability of pulse operation and negative bias voltage, the operation voltage is only 2 V, the current on/off ratio is about 1.24 × 106, and the subthreshold swing is 169.2 mV/dec. The development of KH550 solid electrolyte gate dielectric provides a novel way for the research of oxide thin film transistor.
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    Establishment of a Refined Brain Model for Evaluating Implantation Behavior of Neural Electrode and Research of its Simulated Behavior
    HE Yuxcin (贺雨欣), ZHANG Wenguang (张文光), XU Haotian (胥浩天), XU Yifan (徐倚帆), XU Liyue (许李悦)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 401-.   DOI: 10.1007/s12204-022-2523-5
    Abstract151)      PDF (1512KB)(84)      
    The long-term reliability of the neural electrode is closely related to its implantation behavior. In orderto realize the quantitative research of the implantation behavior in a low-cost and accurate way, a refined brainmodel containing meninges is proposed. First, the expected simulation material was selected through measuringthe elastic modulus based on the method of atomic force microscope indentation technique. As a result, the 2%(mass fraction) agarose gel simulated the gray and white matter, the 7 : 1 (volume ratio) polydimethylsiloxane(PDMS) sheet simulated the pia mater, and the polyvinyl chloride (PVC) film simulated the dura mater. Second,based on designing a three-layer structure mold, the brain model was prepared by inverted pouring to realizea flat implantation surface. Finally, the simulation behavior of the brain model was investigated with the ratbrain as a reference. For mechanical behavior of implantation, the implantation force experienced two peaks bothin the brain model and the rat brain, maximum values of which were 10.17 mN and 7.69 mN respectively. Thelarger implantation force in the brain model will increase the strength requirement for the electrode, but reducethe risk of buckling of that in practical application. For humoral dissolution behavior, the dissolution rates ofthe polyethylene glycol (PEG) coating of the electrode in the brain model and rat brain were 7 000 μm3/s and5 600 μm3/s, respectively. The faster dissolution rate in the brain model will cause the larger thickness of thecoating design but provide sufficient implantable time in practical application. The establishment of the brainmodel and the research of its simulated behavior are beneficial to the size design of the electrode substrate andcoating, and research of the implantation mechanism, and further increase the functional life of the electrode.
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    Fabrication and Characterization of Graphene-Enhanced Hollow Microlattice Materials
    BAO Haisheng (鲍海生), LIU Longquan∗ (刘龙权)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 192-196.   DOI: 10.1007/s12204-021-2339-8
    Abstract146)      PDF (662KB)(53)      
    A method was developed and proposed to fabricate graphene-enhanced hollow microlattice materials, which include the three-dimensional (3D) printing, nanocomposite electroless plating, and polymer etching technologies. The surface morphology and uniformity of as-deposited coatings were systematically characterized and analyzed. Moreover, the mechanical properties of the microlattices were investigated through quasi-static compression tests. The results demonstrated that a uniform Nickel-phossphorous-graphene (Ni-P-G) coating was obtained successfully, and the specific modulus and strength were increased by adding graphene into the microlattice materials. The optimal mass concentration of graphene nanoplatelets was obtained after comparing the specific modulus and strength of the materials with different densities of graphene, and the strength mechanism was discussed.
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    Development of Rehabilitation and Assistive Robots in China: Dilemmas and Solutions
    ZHAO Lingling1*(赵玲玲),GUO Yao2(郭遥)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 382-390.   DOI: 10.1007/s12204-023-2596-9
    Abstract145)      PDF (367KB)(35)      
    China is rapidly becoming an aging society, leading to a significant demand for chronic disease management and personalized healthcare. The development of rehabilitation and assistive robotics in China has gathered significant attention not only in research fields but also in industries. Such robots aim to either guide patients in completing therapeutic training or assist people with impaired functions in performing their daily activities. In the past decades, we have witnessed the advancement in rehabilitation and assistive robotics, with diverse mechanical designs, functionalities, and purposes. However, the construction of dedicated regulations and policies is relatively lagged compared with the flourishing development in research fields. Moreover, these kinds of robots are working or collaborating closely with human beings, bringing unprecedented considerations on ethical issues. This paper aims to provide an overview of major dilemmas in the development of rehabilitation and assistive robotics in China and propose several potential solutions.
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    Calculation of Electrostatic/Magnetic Adhesion Force Between Adjacent Objects Considering Thin Gap Effect
    JIANG Peng (江 鹏), LI Zhibin (李志彬), ZHANG Long (张 龙), LI Jing (李 敬), ZHANG Qun (张 群), GUAN Zhenqun∗ (关振群)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 213-219.   DOI: 10.1007/s12204-021-2317-1
    Abstract144)      PDF (917KB)(27)      
    This paper presents a new approach to evaluating the electrostatic/magnetic adhesion force between two adjacent objects separated by a thin gap. In this approach, instead of generating mesh for the gap, a contact boundary is introduced in the finite element modeling to obtain a reasonable field distribution; then the field in the gap is approximated based on the continuity condition at their interface, so that the adhesion force can be properly calculated. Moreover, a simple equivalent circuit model is introduced to explain how the thin gap influences the adhesion force significantly. Numerical experiments are given to demonstrate the validity of the proposed method and the significance of the thin gap.
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    Analytical Solution of Thermo-Elastic-Plastic Deformation of the Combined Forging Die
    CAO Minye (曹民业), MIAO Hongliang (苗宏量), HU Chengliang∗ (胡成亮), ZHAO Zhen (赵 震)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 280-288.   DOI: 10.1007/s12204-021-2388-z
    Abstract137)      PDF (1429KB)(36)      
    On the multi-layer forging die used in daily life, stressed ring can strength the die structure within elastic deformation and the die material can be self-strengthened through uniform plastic deformation by autofrettage effect, whereas the thermal effect generated during forging process can directly influence the stress state and dimension of the forging die in service. In this study, an analytical solution of the thermo-elastic-plastic deformation in the forging die is derived. The relationships between the radial and circumferential stresses and the temperature distribution, which are directly related to geometric parameters, material properties and working pressure, are determined. This helps to better understand the thermo-elastic-plastic deformation behavior of the die and design the combined forging die to achieve long service life and high accuracy product.
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    Entity Relationship Explanation via Conceptualization
    XIE Chenhao(谢晨昊), LIANG Jiaqing(梁家卿), XIA Yanghua(肖仰华), HWANG Seung-won
    J Shanghai Jiaotong Univ Sci    2023, 28 (6): 695-702.   DOI: 10.1007/s12204-021-2394-1
    Abstract137)      PDF (608KB)(93)      
    Finding an attribute to explain the relationships between a given pair of entities is valuable in many applications. However, many direct solutions fail, owing to its low precision caused by heavy dependence on text and low recall by evidence scarcity. Thus, we propose a generalization-and-inference framework and implement it to build a system: entity-relationship finder (ERF). Our main idea is conceptualizing entity pairs into proper concept pairs, as intermediate random variables to form the explanation. Although entity conceptualization has been studied, it has new challenges of collective optimization for multiple relationship instances, joint optimization for both entities, and aggregation of diluted observations into the head concepts defining the relationship. We propose conceptualization solutions and validate them as well as the framework with extensive experiments.
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    Real-Time Slice-to-Volume Registration-Based Autonomous Navigation for Robot-Assisted Thyroid Biopsy
    LI Jian1 (李坚),WANG Xingchao1 (王星超),ZHONG Min2 (钟敏),ZHENG Jian2(郑剑),SUN Zhenglong1*(孙正隆)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 330-338.   DOI: 10.1007/s12204-023-2606-y
    Abstract127)      PDF (1034KB)(22)      
    With advancements in medical imaging and robotic technology, the idea of fully autonomous diagnosis and treatment has become appealing, from ethereal to tangible. Owing to its characteristics of non-invasiveness, non-radiation, and fast imaging speed, ultrasonography has been increasingly used in clinical practice, such as in obstetrics, gynecology, and surgical puncture. In this paper, we propose a real-time image-based visual servo control scheme using a hybrid slice-to-volume registration method. In this manner, the robot can autonomously locate the ultrasound probe to the desired posture according to preoperational planning, even in the presence of disturbances. The experiments are designed and conducted using a thyroid biopsy phantom model. The results show that the proposed scheme can achieve a refresh rate of up to 30 Hz and a tracking accuracy of (0.52±0.65) mm.
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    Enhancement of Pinching Grasping Robustness Using a Multi-Structure Soft Gripper
    LI Linlin (李林霖), GAO Feiyang (高飞扬), ZHENG Xiongfei(郑雄飞), ZHANG Liming(张黎明), LI Shijie (李世杰), WANG Heran(王赫然)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 307-311.   DOI: 10.1007/s12204-022-2508-4
    Abstract127)      PDF (2071KB)(41)      
    Recently, soft grippers have garnered considerable interest in various fields, such as medical rehabilitation, due to their high compliance. However, the traditional PneuNet only reliably grasps medium and large objects via enveloping grasping (EG), and cannot realize pinching grasping (PG) to stably grasp small and thin objects as EG requires a large bending angle whereas PG requires a much smaller one. Therefore, we proposed a multi-structure soft gripper (MSSG) with only one vent per finger which combines the PneuNet in the proximal segment with the normal soft pneumatic actuator (NSPA) in the distal segment, allowing PG to be realized without a loss in EG and enhancing the robustness of PG due to the height difference between the distal and proximal segments. Grasping was characterized on the basis of the stability (finger bending angle describes) and robustness (pull-out force describes), and the bending angle and pull-out force of MSSG were analyzed using the finite element method. Furthermore, the grasping performance was validated using experiments, and the results demonstrated that the MSSG with one vent per finger was able to realize PG without a loss in EG and effectively enhance the PG robustness.
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    High-Performance Single-Side Fabricated (111)-Silicon Dual-Cantilever Accelerometer with Squeeze-Film Air Damping Modulation
    JIAO Ding (焦 鼎), NI Zao (倪 藻), WANG Jiachou (王家畴), LI Xinxin∗ (李昕欣)
    J Shanghai Jiaotong Univ Sci    2023, 28 (2): 197-206.   DOI: 10.1007/s12204-021-2288-2
    Abstract123)      PDF (1510KB)(35)      
    This study proposes a novel design and micromachining process for a dual-cantilever accelerometer. Comb and curved-surface structures are integrated into the sensing structure to modulate the squeeze-film damping, thus effectively optimizing the response frequency bandwidth. Owing to the high stress concentration on the dual-cantilever integrated with a fully sensitive piezoresistive Wheatstone bridge, a high sensitivity to acceleration is achieved. In addition, the dual-cantilever accelerometer is fabricated using a specifically developed low-cost and high-yield (111)-silicon single-side bulk-micromachining process. The test results show that the proposed dualcantilever accelerometer exhibits a sensitivity of 0.086—0.088 mV/g/3.3 V and a nonlinearity of ±(0.09%—0.23%) FS (full-scale). Based on dynamic characterization, an adequate frequency bandwidth of 2.64 kHz is verified. Furthermore, a resonant frequency of 4.388 kHz is measured, and a low quality factor (Q) of 7.62 is obtained, which agrees well with the design for air-damping modulation. The achieved high performance renders the proposed dual-cantilever accelerometer promising in applications such as automotive and consumer electronics.
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    Early Detection Methods of Deep Tissue Pressure Injuries: A Systematic Review
    JIA Jingyil (贾菁怡),LI Zhengyi1,2 (李正裔),PENG Linjing1 (彭琳晶),YAO Yifeil* (姚怡飞)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 526-.   DOI: 10.1007/s12204-022-2518-2
    Abstract117)      PDF (551KB)(97)      
    Deep tissue pressure injuries (DTPIs) have witnessed a growing prevalence in hospitals and other health care units especially among individuals with pathological conditions that give rise to restricted mobility, impaired sensation, and reduced tissue tolerance. The etiology of DTPIs has been a subject of controversy, to which several explanatory models have been proposed, including direct mechanical insult, ischemia-reperfusion, lymphatic occlusion, and inflammatory cytokines. In line with these pathophysiological scenarios, ultrasound, subepidermal moisture detection, and biomarker technologies have been proposed as potential early detection methods of DTPIs. This paper provides a systematic review involving these three methods. The conclusion is that combining and implementing these methods at different time periods during DTPIs development and progression respectively is likely to be the most universal, effective and promising way for DTPIs diagnosis.
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    Improving Colonoscopy Polyp Detection Rate Using Semi-Supervised Learning
    YAO Leyul (姚乐宇),HE Fan1,3 (何凡), PENG Haixia2* (彭海霞), WANG Xiaofeng2 (王晓峰),ZHOU Lu2(周璐), HUANG Xiaolin1,3* (黄晓霖)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 441-.   DOI: 10.1007/s12204-022-2519-1
    Abstract117)      PDF (496KB)(55)      
    Colorectal cancer is one of the biggest health threats to humans and takes thousands of lives every year.Colonoscopy is the gold standard in clinical practice to inspect the intestinal wall, detect polyps and remove polypsin early stages, preventing polyps from becoming malignant and forming colorectal cancer instances. In recentyears, computer-aided polyp detection systems have been widely used in colonoscopies to improve the qualityof colonoscopy examination and increase the polyp detection rate. Currently, the most efficient computer-aidedsystems are built with machine learning methods. However, developing such a computer-aided detection systemrequires experienced doctors to label a large number of image data from colonoscopy videos, which is extremelytime-consuming, laborious and expensive. One possible solution is to adopt a semi-supervised learning, which canbuild a detection system on a dataset where part of its data is not necessary to be labeled. In this paper, on thebasis of state-of-the-art object detection method and semi-supervised learning technique, we design and implementa semi-supervised colonoscopy polyp detection system containing four main steps: running standard supervisedtraining with all labeled data; running inference on unlabeled data to obtain pseudo labels; applying a set ofstrong augmentation to both unlabeled data and pseudo label; combining labeled data, and unlabeled data withits pseudo labels to retrain the detector. The semi-supervised learning system is evaluated both on public datasetand our original private dataset and proves its effectiveness. Also, the inference speed of the semi-supervisedlearning system can meet the requirement of real-time operation.
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    Real-Time Calculation Method for Temperature Distribution of Temperature-Controlled Radiofrequency Ablation
    WANG Xuewei (王雪维),WANG Yifei (王逸飞),ZHANG Aili* (张爱丽)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 411-.   DOI: 10.1007/s12204-022-2481-y
    Abstract113)      PDF (1219KB)(69)      
    Precise temperature control and temperature distribution prediction are of great significance forradiofrequency ablation. This research proposes a real-time calculation method for the temperature distribution of radiofrequency ablation combined with proportional-integral temperature control. The thermo-electricalcoupling was simplified into a linear relationship based on the study of the influence of temperature-dependentelectrical conductivity and thermal conductivity on the PI-controlled radiofrequency ablation temperature distribution, which increases the computational efficiency by 150 times. The average calculation time for radiofrequencyablation of 10 min is about 23 s, and the difference between the calculation results of this method and that fromCOMSOL Multiphysics is no more than 1 ?C. This method is not only used for single-probe, but also for doubleprobe radiofrequency ablation in this paper.
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    Review of Power-Assisted Lower Limb Exoskeleton Robot
    HE Guisong (贺贵松), HUANG Xuegong (黄学功), LI Feng (李峰), WANG Huixing (汪辉兴)
    J Shanghai Jiaotong Univ Sci    2024, 29 (1): 1-15.   DOI: 10.1007/s12204-022-2489-3
    Abstract112)      PDF (1195KB)(25)      
    Power-assisted lower limb exoskeleton robot is a wearable intelligent robot system involving mechanics,materials, electronics, control, robotics, and many other fields. The system can use external energy to provide additional power to humans, enhance the function of the human body, and help the wearer to bear weight that is previously unbearable. At the same time, employing reasonable structure design and passive energy storage can also assist in specific actions. First, this paper introduces the research status of power-assisted lower limb exoskeleton robots at home and abroad, and analyzes several typical prototypes in detail. Then, the key technologies such as structure design, driving mode, sensing technology, control method, energy management, and human-machine coupling are summarized, and some common design methods of the exoskeleton robot are summarized and compared. Finally, the existing problems and possible solutions in the research of power-assisted lower limb exoskeleton robots are summarized, and the prospect of future development trend has been analyzed.
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    Calibration Technology of Optical Fiber Strain Sensor
    CHEN Gang(陈刚), LIU Hongyue(刘宏月), GAO Ruiriang(高瑞翔)
    J Shanghai Jiaotong Univ Sci    2023, 28 (5): 551-559.   DOI: 10.1007/s12204-022-2406-9
    Abstract108)      PDF (1122KB)(78)      
    As one of the hotspots of sensing technology at present, optical fiber sensor has the characteristics of small size, anti-electromagnetic interference, and easy networking, which plays an irreplaceable role in multiphysics parameter monitoring of complex electromagnetic environments. The precise calibration of the optical fiber strain sensor has great practical value in prolonging the survival rate of the sensor, improving the measurement accuracy, and meeting the needs of long-term monitoring. By reviewing the research status of strain sensor calibration method and fiber optic strain sensor calibration method, the advantages and disadvantages of the main methods are analyzed separately from the static and dynamic perspectives, and the development prospect of the calibration technology of optic fiber strain sensor is summarized.
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    Dlung: Unsupervised Few-Shot Diffeomorphic Respiratory Motion Modeling
    CHEN Peizhi1,2* (陈培芝), GUO Yifan1 (郭逸凡),WANG Dahan1,2 (王大寒), CHEN Chinling1,3,4* (陈金铃)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 536-.   DOI: 10.1007/s12204-022-2525-3
    Abstract103)      PDF (1719KB)(70)      
    Lung image registration plays an important role in lung analysis applications, such as respiratory motion modeling. Unsupervised learning-based image registration methods that can compute the deformation without the requirement of supervision attract much attention. However, it is noteworthy that they have two drawbacks: they do not handle the problem of limited data and do not guarantee diffeomorphic (topologypreserving) properties, especially when large deformation exists in lung scans. In this paper, we present an unsupervised few-shot learning-based diffeomorphic lung image registration, namely Dlung. We employ fine-tuning techniques to solve the problem of limited data and apply the scaling and squaring method to accomplish the diffeomorphic registration. Furthermore, atlas-based registration on spatio-temporal (4D) images is performed and thoroughly compared with baseline methods. Dlung achieves the highest accuracy with diffeomorphic properties. It constructs accurate and fast respiratory motion models with limited data. This research extends our knowledge of respiratory motion modeling.
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    Substrate Stiffness and Topography Affect the Morphology of Human Fibroblasts in Mechanical Microenvironment
    LIU Yang-,2 (刘阳), WANG Yajing- (王雅靖),WEN Daweil (温大渭),ZHANG Quanyoul (张全有), WANG Li (王立),AN Meiwen1* (安美文), LIU Yong3* (刘勇)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 495-.   DOI: 10.1007/s12204-022-2542-2
    Abstract98)      PDF (1267KB)(21)      
    Hyperplastic scar is a common fibrotic disease that may ultimately lead to severe dysfunction anddeformity, causing physical and psychological distress. Therefore, we aim to evaluate the effect of the mechanicalmicroenvironment of scar substrates on the morphology of human fibroblasts (HFbs). The micro-modular fabrication technique was used to design a new cross-groove topology and to construct four elastic substrates withthe stiffness of 19.3 kPa and 90.1 kPa coupled with parallel groove and cross groove, respectively, to simulate themechanical microenvironment of skin wounds and scar tissues. The morphological changes in HFbs in differentsubstrates were observed, and the changes in the cell-long axis length, area, and the angle between cell-long axisand grooves were recorded. Immunofluorescence staining was performed to observe the distribution of microfilaments. The results indicated that substrate stiffness and topography affected the morphology of HFbs. The cellswere elongated in parallel grooves as well as in the area where cross grooves restricted groove length, the celllength was restricted, and the angle between the long axis and the groove was increased. The topography exertedno significant effect on the cell area, but the cell area increased with increasing the stiffness. The parallel groovepromoted the expression of the F-actin to a certain extent, and the fluorescence intensity of F-actin decreased withincreasing the stiffness. Studying the effect of the mechanical microenvironment of substrates on HFb morphologyis of great importance for understanding the mechanisms of scar formation and prevention.
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    Novel Visualization Tool for Percutaneous Renal Puncture Training Using Augmented Reality Technology
    YU Jiaqi1 (于佳琪),WANG Shuyi1* (王殊轶),WANG Yuqil (王浴屺),XIE Hua2 (谢华), WU Zhangleil (吴张檑),FU Xiaonil (付小妮),MA Bangfeng1 (马邦峰)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 517-.   DOI: 10.1007/s12204-022-2554-y
    Abstract96)      PDF (1511KB)(77)      
    We aim to develop a novel visualization tool for percutaneous renal puncture training based on augmented reality (AR) and compare the needle placement performance of this AR system with ultrasound-guidedfreehand navigation in phantoms. A head-mounted display-based AR navigation system was developed usingthe Unity3D software and Visual Studio to enable the overlay of the preoperative needle path and the complexanatomical structures onto a phantom in real time. The spatial location of the stationary phantom and the percutaneous instrument motion were traced by a Qualisys motion capture system. To evaluate the tracking accuracy,15 participants (7 males and 8 females) performed a single needle insertion using AR navigation (the number ofpunctures n = 75) and ultrasound-guided freehand navigation (n = 75). The needle placement error was measuredas the Euclidean distance between the actual needle tip and the virtual target by MicronTracker. All participantsdemonstrated a superior needle insertion efficiency when using the AR-assisted puncture method compared withthe ultrasound-guided freehand method. The needle insertion error of the ultrasound-guided method showed anincreased error compared with the AR method (5.54 mm ± 2.59 mm, 4.34 mm ± 2.10 mm, respectively, p < 0.05).The ultrasound-guided needle placements showed an increased time compared with the AR method (19.08 s ±3.59 s, 15.14 s ± 2.72 s, respectively, p < 0.000 1). Our AR training system facilitates the needle placement performance and solves hand-eye coordination problems. The system has the potential to increase efficiency andeffectiveness of percutaneous renal puncture training.
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    Gene Expression Profiling Identifies Potential Biomarkers for Colorectal Cancer Using NanoString nCounter Assay
    ZHAO Hui (赵晖),WEN Baiqing (文柏清),KANG Yani*(康亚妮)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 432-.   DOI: 10.1007/s12204-022-2440-7
    Abstract89)      PDF (626KB)(58)      
    Colorectal cancer (CRC) is one of the most common malignancies worldwide. Development of predictivemolecular markers may help to achieve the best outcome in clinic. The purpose of this study is to identify thedifferentially expressed genes and new potential predictive and prognostic molecular biomarkers for CRC. Inthis study, CRC and matched normal tissues acquired from the same patient were used to extract total RNA.The NanoString nCounter assay was applied to determine the differentially expressed genes. The results werethen validated by using the Cancer Genome Atlas data. Finally, we identified 27 genes that revealed significantcorrelation with CRC in the tumor tissue. Several genes in the pan-cancer panel showed significant differentialexpression, which were more universal than others in the CRC tissue. Since some of them have not been reportedas being directly related to CRC yet, future mechanism studies can be designed based on this study. Our studydemonstrated NanoString nCounter assay could serve as an alternative approach for gene expression analysis andidentified several unreported differently expressed genes in CRC patients, which may provide some importantclues for more in-depth study of CRC and serve as potential predictive molecular biomarkers for clinical diagnosisapplication.
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    Novel Scheme for Essential Proteins Identification Based on Improved Multicriteria Decision Making
    LU Pengli1* (卢鹏丽),CHEN Yuntian1 (陈云天), LIAO Yonggang2 (廖永刚)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 418-.   DOI: 10.1007/s12204-023-2584-0
    Abstract88)      PDF (1359KB)(51)      
    Identifying essential proteins from protein-protein interaction networks is important for studies onbiological evolution and new drug’s development. Most of the presented criteria for prioritizing essential proteinsonly focus on a certain attribute of the proteins in the network, which suffer from information loss. In order toovercome this problem, a relatively comprehensive and effective novel method for essential proteins identificationbased on improved multicriteria decision making (MCDM), called essential proteins identification-technique fororder preference by similarity to ideal solution (EPI-TOPSIS), is proposed. First, considering different attributes ofproteins, we propose three methods from different aspects to evaluate the significance of the proteins: gene-degreecentrality (GDC) for gene expression sequence; subcellular-neighbor-degree centrality (SNDC) and subcellular-indegree centrality (SIDC) for subcellular location information and protein complexes. Then, betweenness centrality(BC) and these three methods are considered together as the multiple criteria of the decision-making model.Analytic hierarchy process is used to evaluate the weights of each criterion, and the essential proteins are prioritizedby an ideal solution of MCDM, i.e., TOPSIS. Experiments are conducted on YDIP, YMIPS, Krogan and BioGRIDnetworks. The results indicate that EPI-TOPSIS outperforms several state-of-the-art approaches for identifyingthe essential proteins through the performance measures.
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    On Flexible Trajectory Description for Effective Rigid Body Motion Reproduction and Recognition
    YANG Jian xin(杨健鑫),GUo Yao*(郭遥)
    J Shanghai Jiaotong Univ Sci    2023, 28 (3): 339-347.   DOI: 10.1007/s12204-023-2604-0
    Abstract88)      PDF (1121KB)(21)      
    Recognizing and reproducing spatiotemporal motions are necessary when analyzing behaviors and movements during human-robot interaction. Rigid body motion trajectories are proven as compact and informative clues in characterizing motions. A flexible dual square-root function (DSRF) descriptor for representing rigid body motion trajectories, which can offer robustness in the description over raw data, was proposed in our previous study. However, this study focuses on exploring the application of the DSRF descriptor for effective backward motion reproduction and motion recognition. Specifically, two DSRF-based reproduction methods are initially proposed, including the recursive reconstruction and online optimization. New trajectories with novel situations and contextual information can be reproduced from a single demonstration while preserving the similarities with the original demonstration. Furthermore, motion recognition based on DSRF descriptor can be achieved by employing a template matching method. Finally, the experimental results demonstrate the effectiveness of the proposed method for rigid body motion reproduction and recognition.
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    Applications of Polypeptide Hydrogels in Cartilage-Regeneration Engineering
    HU Yinghan1 (胡颖涵),ZHU Zegu1 (朱泽宇), TENG Lin2 (滕林), HE Yushi3 (何雨石),ZOU Derong1 (邹德荣),LU Jiayu1*(陆家瑜)
    J Shanghai Jiaotong Univ Sci    2023, 28 (4): 468-.   DOI: 10.1007/s12204-022-2507-5
    Abstract83)      PDF (3065KB)(20)      
    Articular cartilage defects are considered to be associated with the development of osteoarthritis. Research on relevant tissue regeneration is important in the treatment of osteoarthritis. The scaffolds applied incartilage regeneration should have good histocompatibility and mechanical properties, as well as no cytotoxicity,and promote the proliferation and differentiation of seed cells. Different combinations of peptide sequences inpolypeptide hydrogels endow them with unique characteristics including excellent biodegradability and accuratesimulation of the extracellular matrix of chondrocytes to maintain the stability of the chondrogenic phenotypeand facilitate articular hyaline cartilage regeneration. Thus, the application of polypeptide hydrogels for cartilage regeneration has a bright future. In this study, the research progress of polypeptide hydrogels used incartilage-regeneration engineering is systematically reviewed. The characteristics, limitations, and prospects ofthese materials are evaluated.
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