Fuzzy Sliding Mode Active Disturbance Rejection Control of an Autonomous Underwater Vehicle-Manipulator System

In this paper, a fuzzy sliding mode active disturbance rejection control(FSMADRC) scheme is proposed for an autonomous underwater vehicle-manipulator system(AUVMS) with a two-link and three-joint manipulator. First, the AUVMS is separated into nine subsystems, and the combined effects of dynamic uncertainties, hydrodynamic force, unknown disturbances, and nonlinear coupling terms on each subsystem are lumped into a single total disturbance. Next, a linear extended state observer(LESO) is presented to estimate the total disturbance. Then, a sliding mode active disturbance rejection control(SMADRC) scheme is proposed to enhance the robustness of the control system. The stability of the SMADRC and the estimation errors of the LESO are analyzed. Because it is difficult to simultaneously adjust several parameters for a LESO-based SMADRC scheme, a fuzzy logic control(FLC) scheme is used to formulate the FSMADRC to determine the appropriate parameters adaptively for practical applications. Finally, two AUVMS tasks are illustrated to test the trajectory tracking performance of the closed-loop system and its ability to reject and attenuate the total disturbance. The simulation results show that the proposed FSMADRC scheme achieves better performance and consume less energy than conventional PID and FLC techniques.

EAST-Educational Adaptive-optics Solar Telescope

For the public having a better understanding of solar activities,the Educational Adaptive-optics Solar Telescope(EAST)was built in July 2021 and is located at the Shanghai Astronomy Museum.The EAST consists of a 65 cm aperture solar telescope with a 177-element adaptive optics system and two-channel high resolution imaging system at the Hαand TiO bands,in addition to three full disk solar telescopes at CaK,Hαand TiO bands equipped on the tube of the main telescope.In this paper,the configuration of the EAST is described.Its performance and on-sky observational results are presented.The EAST,to our knowledge,is the most advanced solar telescope for the popularization of science in the world.Due to its excellent performance,the data acquired by the EAST can also be used for research on solar physics and space weather prediction.

English & Chinese Kinship Terms and Their Cultural Roots

Kinship terms system is one of the most common features in the world,but different countries have different kinship expressions.This paper mainly states the differences between English and Chinese kinship terms and Cultural differences between English and Chinese kinship terms.The cultural differences between English and Chinese kinship terms exist in several aspects.The causes of differences between English and Chinese kinship terms are various,and the major aspects we will consider are history,like different patriarchal clan system;worldview,like different ideas of birth and numbers of birth;different social organization and system changes of social system.

Using FCM to Select Samples in Semi-Supervised Classification

For a semi-supervised classification system, with the increase of the training samples number, the system needs to be continually updated. As the size of samples set is increasing, many unreliable samples will also be increased. In this paper, we use fuzzy c-means （FCM） clustering to take out some samples that are useless, and extract the intersection between the original training set and the cluster after using FCM clustering. The intersection between every class and cluster is reliable samples which we are looking for. The experiment result demonstrates that the superiority of the proposed algorithm is remarkable.

ECC-Based RFID Authentication Protocol

The radio frequency identification(RFID)technology has been widely used so far in industrial and commercial applications.To develop the RFID tags that support elliptic curve cryptography(ECC),we propose a scalable and mutual authentication protocol based on ECC.We also suggest a tag privacy model that provides adversaries exhibiting strong abilities to attack a tag’s privacy.We prove that the proposed protocol preserves privacy under the privacy model and that it meets general security requirements.Compared with other recent ECCbased RFID authentication protocols,our protocol provides tag privacy and performs the best under comprehensive evaluation of tag privacy,tag computation cost,and communications cost.

A Sentinel-Based Peer Assessment Mechanism for Collaborative Learning

This paper introduces a novel mechanism to improve the performance of peer assessment for collaborative learning.Firstly,a small set of assignments which have being pre-scored by the teacher impartially,are introduced as“sentinels”.The reliability of a reviewer can be estimated by the deviation between the sentinels’scores judged by the reviewers and the impartial scores.Through filtering the inferior reviewers by the reliability,each score can then be subjected into mean value correction and standard deviation correction processes sequentially.Then the optimized mutual score which mitigated the influence of the subjective differences of the reviewers are obtained.We perform our experiments on 200 learners.They are asked to submit their assignments and review each other.In the experiments,the sentinel-based mechanism is compared with several other baseline algorithms.It proves that the proposed mechanism can effectively improve the accuracy of peer assessment,and promote the development of collaborative learning.

Conversational Analysis of Power and Solidarity in Chinese Community Correction Discourse

This paper mainly discusses the power and solidarity among participants in the community correction discourse from sociolinguistic perspective by adopting the methodology of conversation analysis.Through the comparative study of the steps of Initial Evaluation and Entry Ceremony in community correction,this paper analyses the power and solidarity in the features of adjacency pair and turn-taking,and finds that the step of Initial Evaluation is relatively negotiable and represents the social relationship of solidarity,while the step of Entry Ceremony stresses more on social distance and power relationship.The reasons that cause the power and solidarity in the Initial Evaluation and the Entry Ceremony from the perspective of social identity and social purposes are also explored.

How to be a Good Observer in English Class

How to improve the level of English teaching has always been a problem for university English teachers.The paper suggests the listeners should change the traditional listening methods and pay more attention to the following four ways.To be a good observer and commentator,so as to help the teacher to improve their English educational quality and better serve the students with high quality and high skills.

C-doped BiOCl/Bi_(2)S_(3) heterojunction for highly efficient photoelectrochemical detection and photocatalytic reduction of Cr(VI)

Novel C-BiOCl/Bi_(2)S_(3) composites are prepared by hydrothermal C doping in BiOCl and in-situ growth of Bi_(2)S_(3) on C-BiOCl.Compared with BiOCl,C-BiOCl has a larger exposed surface area and can effectively absorb visible light.The construction of a heterojunction in C-BiOCl/Bi_(2)S_(3) further promotes the separation and transfer of photogenerated carriers.With improved photoelectric properties,the optimized 5C-BiOCl/5Bi_(2)S_(3) is applied as a dual-functional composite for photoelectrochemical(PEC)detection and photocatalytic(PC)reduction of Cr(VI).The 5C-BiOCl/5Bi_(2)S_(3) shows a linear range of 0.02-80μM for PEC cathodic detection of Cr(VI)with a detection limit of 0.01628μM.Additionally,99.5%of Cr(VI)can be removed via absorption and PC reduction by 5C-BiOCl/5Bi_(2)S_(3),with the reduction rate constant(k)336 times higher than that of BiOCl.

First light of the 1.8-m solar telescope–CLST

Large-aperture solar telescopes play an important role in solar observations and research,and require high temporal and spatial resolution[1].To solve some fundamental problems such as the solar dynamo,coronal heating,and the triggering of major solar eruptions,the spatial resolution for solar-atmosphere observation should reach at least 0.1 arcsec[2].

A two-photon mitotracker based on a naphthalimide fluorophore:Synthesis, photophysical properties and cell imaging

PAHPN. a naphthalimide-based mitotracker with reasonable two-photon excitation emission activity and polarity-sensitive fluorescence properties has been efficiently synthesized and studied in twophoton, co-localization, and FLIM imaging.

Determination of amphetamines,ketamine and their metabolites in hair with high-speed grinding and solid-phase microextraction followed by LC-MS

A novel hair sample pre-treatment method based on high-speed grinding and solid-phase microextraction(SPME)had been applied for the determination of amphetamines,ketamine and their metabolites in hair samples by liquid chromatography mass spectrometry(LC-MS).A 20mg sample of hair was ground with 2 mL of saturated sodium carbonate solution using a high-efficiency hair grinder with 70 Hz osillation for 2min at 4℃.After centrifuging,1.5mL of the supernatant was transferred and treated with SPME by direct immersion(DI-SPME).The target analytes extracted by fibre were desorbed and analysed using LC-MS.Under the optimum conditions,a recovery of 90.2%-95.8%was obtained for all analytes.The analytical method was linear for all analytes in the range from 0.2 to 10 ng/mg with the correlation coefficient ranging from 0.9985 to 0.9993.The detection limits for all analytes were estimated to be 0.067 ng/mg.The accuracy(mean relative error)was within±6.9%and the precision(relative standard error)was less than 6.8%.The combination of high-speed grinding of hair and SPME had the advantages of being easy to perform,environment-friendly and high in detection sensitivity.The proposed method offered an altermative ana lytical approach for the sensitive detection of drugs in hair samples for forensic purposes.