Design of Preview Controller for Linear Continuous-time Systems with Input Delay

Yonglong Liao,Fucheng Liao 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.3

This paper makes it possible to design a preview controller for linear continuous-time systems with input delay, which expands the preview control theory. An augmented error system is established. And a variable substitution is used to transform the delay preview control system into a delay-free one whose preview controller uses the future value of the augmented state vector. The future value of the augmented state vector is estimated by the information of the current state vector, the control input on the past time window, and the reference signal on the future time window. Under the assumption of zero initial conditions, a simplified controller with both delay compensation and preview compensation is obtained for the original system. In addition, a preview controller with full-order observer is offered. Finally, simulation results are presented to illustrate the effectiveness and robustness of the controller.

Exposed Aggregate Detection of Stilling Basin Slabs Using Attention U-Net Network

Yonglong Li,Xiaoxia Li,Haoran Wang,Shuang Wang,Shuhao Gu,Hua Zhang 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.6

Exposed aggregate is a typical feature of the abrasion erosion in stilling basin slabs concrete surface. Although a variety of underwater robots are designed for inspection, the exposed aggregate detection for identifying abrasion is often done by manual work. The scarcity of image samples, large differences in aggregate size, color and shape are the main difficulties in automatic detection. To address this problem, an improved Attention U-Net deep fully convolutional network-based detection method was proposed. To realize this method, underwater images in site were captured via a self-developed operated underwater robot. Through randomly separating and the cropping of the 128 underwater images, the 512×512 pixels images dataset was built according to the ratio of 8:1:1, including 408 training images, 52 validation images and 52 test images. After the data augmentation, loss function and the optimizer were carefully designed and selected, the proposed Attention U-Net architecture was evaluated on this dataset. For comparative research, the full convolution network (FCN) and U-Net network were trained with the same training and validation dataset. The performance comparison on the test dataset showed that the Attention U-Net architecture has better detection accuracy.

A design method of preview controller for linear continuous-time systems with multiple input delays

Yonglong Liao,Fucheng Liao 제어로봇시스템학회 2017 제어로봇시스템학회 국제학술대회 논문집 Vol.2017 No.10

This paper studies a preview control problem for a class of linear continuous-time systems with multiple input delays. Firstly, the preview problem is transformed into a regulation one via constructing an augmented error system. Secondly, a variable substitution is given to eliminate the input delays. Then, based on the solution of an algebraic Riccati equation, a controller with delay compensation and preview compensation is obtained. Furthermore, the existence conditions of the preview controller and the asymptotic tracking properties of the closed-loop system are discussed. Finally, a numerical simulation is given to illustrate the effectiveness of the design method.

Research and Improvement of Ordered Multisignature Algorithm in Random Oracle Model

Yonglong Tang 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.2

Ordered multisignature allows signers attest to a common message as well as the order in whey they signed. Unlike multi-signature, aggregate signature aggregate signature scheme provides a method to aggregate signature by signature on different messages. In this paper, we presented an ordered multisignature provably secure without random oracles. We mainly focus on construction of perfectly hiding and computationally binding commitment (PHCBC). Our construction was based on the signature scheme of waters and is computationally suitable for practical application. Experiment showed that this scheme was suitable for the practical application with high computing efficiency. By transmitting individual signatures into a multi-signature, multi-signature scheme can greatly save communication cost.

중국 농촌 토지 “3권분할(三權分置)”제도에 관한 연구

YU YONGLONG,CHEN JUNJIANG 국민대학교 법학연구소 2021 법학논총 Vol.34 No.2

“3권분할(三權分置)”(“3권분리”라고도 함) 개혁은 농촌 가정 생산량 도급제(家庭联产承包责任制)에 이어 중국 농촌의 토지 제도 개혁을 심화시키는 또 하나의 중대한 정책 제도 혁신이다. 2018년 12월 29일 개정된 「중화인민공화국 농촌토지도급법」(이하 새 「농촌토지도급법」) 제9조에 따르면, 도급농가는 자원에 근거하여 토지도급경영권을 토지도급권(土地承包权)과 토지경영권(土地经营权)으로 분리 배치할 수 있음으로써 중앙정책문서에 있는 농지 “3권분할(三權分置)” 개혁의 입법표현을 처음으로 완료하였다. 이번에 개정된 「농촌토지도급법」은 정책적 차원의 농촌도급지 “3권분할(三權分置)”의 개혁성과를 입법으로 고정한 것이다. 이에 따라 가족도급제도 중의 농가는 자발적으로 토지경영권을 다른 사람에게 이전할 수 있고 농지 “3권분할(三權分置)”이라는 권리의 새로운 배치가 이루어졌다. 3권분할(三權分置) 개혁의 목적은 가장 필요한 주체로 토지를 이전하는 데 그 내재된 가치를 충분히 발휘하도록 하는 것이다. 농촌도급지에 농민 집단소유권, 농민 집단구성원권(农民集体成员权), 농가 토지 도급경영권 및 토지경영권을 뼈대로 하는 농지 권리체계를 구축하는 것은 농지 집단소유권 허위화 문제를 해결하는데 유리하고, 또한 농지의 생산요소 속성 등을 불러일으키는데도 있으며, 따라서 “3권분할(三權分置)” 개혁의 목적에 더욱 부합한다. 농촌 토지소유권과 도급권, 경영권의 “3권분할(三權分置)”을 실행하는 것은 중국 농촌토지제도의 새로운 개혁의 기본방향이지만, 어떻게 분할 후 “3권” 간의 권리관계를 정립하고 그에 따라 관련 제도를 구축할지는 여전히 시급한 현실적인 문제이다. The reform of “three powers separation”(also called “three powers separation”) is another important policy system innovation that deepened the reform of China"s rural land system after the household contract responsibility system. According to Article 9 of the Rural Land Contracting Law of the People"s Republic of China (hereinafter referred to as the new Rural Land Contracting Law) amended on December 29, 2018, it is clear that the contractor"s land contracting right and land management right can be divided into the land contracting right and land management right, and the legislative expression on the central policy document has been completed. It can be said that the newly revised Rural Land Contracting Law has fixed the achievements of the reform of “three powers separation” of rural land contracting sites at the policy level. In the form of family contract, the peasant households may voluntarily transfer the land management rights to others and retain the land contracting rights, thus forming a new allocation of the rights of “three powers” in agricultural land. The purpose of the three-pronged decentralization reform is to make land flow into the hands of the most needy entity to bring its value into full play. The establishment of a system of farmland rights based on peasant collective ownership, peasant collective membership, peasant household land contracting management and land management rights is helpful to solve the problem of weak agricultural land collective ownership, and to stimulate the property of production factors of farmland, which is in accordance with the purpose of the reform. The implementation of “three powers separation” is the basic direction of China"s rural land system, but how to define the relationship of rights between the three powers after separation is still a practical problem that needs to be solved.

A Method for Service Evaluation Based on Fuzzy Theory for Cloud Computing

( Liangmin Guo ),( Yonglong Luo ),( Xiaokang He ),( Guiyin Hu ),( Yan Dong ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.4

Aiming at the phenomenon of false information issued by service providers in cloud computing environment, a method for service evaluation based on fuzzy theory is put forward in this paper. According to the quality of services provided by cloud service providers and their behavior during interactions, a trust relationship between cloud service providers and cloud service consumers is established, which can be quantified by using fuzzy theory. The quality of services is evaluated by drawing on the trust relationship. In our method, the recommendation credibility of a cloud service consumer is determined through behavior similarity with evaluators and a praise factor. The introduction of the praise factor better suits the phenomenon of a high-quality service getting more repeat customers. The negative impact of dishonest customers is reduced, and the accuracy of trust and cloud service quality evaluation is improved by introducing a confidence factor that can be dynamically adjusted. The experimental results show that our method can effectively and accurately evaluate the trust value and service quality of providers, while weakening the influence of dishonest consumers, and quickly detect dishonest service providers. This is beneficial for consumers trying to find high quality service providers for similar services.

Tourism Destination Recommender System for the Cold Start Problem

( Xiaoyao Zheng ),( Yonglong Luo ),( Zhiyun Xu ),( Qingying Yu ),( Lin Lu ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.7

With the advent and popularity of e-commerce, an increasing number of consumers prefer to order tourism products online. A recommender system can help these users contend with information overload; however, such a system is affected by the cold start problem. Online tourism destination searching is a more difficult task than others on account of its more restrictive factors. In this paper, we therefore propose a tourism destination recommender system that employs opinion-mining technology to refine user preferences and item opinion reputations. These elements are then fused into a hybrid collaborative filtering method by combining user- and item-based collaborative filtering approaches. Meanwhile, we embed an artificial interactive module in our recommender system to alleviate the cold start problem. Compared with several well-known cold start recommendation approaches, our method provides improved recommendation accuracy and quality. A series of experimental evaluations using a publicly available dataset demonstrate that the proposed recommender system outperforms existing recommender systems in addressing the cold start problem.

Preview Repetitive Control for Linear Continuous-time System

Li Li,Xiaohua Meng,Yonglong Liao 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.2

This paper presents a preview repetitive control for linear continuous-time systems when a periodic reference signal is previewed. First, an augmented two-dimensional (2D) system is constructed by state augmentation technique and a 2D model approach. Then, the preview repetitive control laws are proposed for the augmented 2D system, which transforms the preview repetitive control problem into a stabilization problem. Using Lyapunov functions, sufficient conditions for asymptotic stability of the 2D continuous-discrete system are derived in the form of linear matrix inequalities (LMIs). The design of a preview repetitive controller is proposed through the LMI approach. Finally, the developed design techniques are applied to two examples. The simulation results demonstrate the validity of the proposed method.

Distribution and bioaccumulation of lead in the coastal watersheds of the Northern Bohai and Yellow Seas in China

Kong, Peiru,Luo, Wei,Lu, Yonglong,Wang, Tieyu,Jiao, Wentao,Hu, Wenyou,Naile, Jonathan E.,Khim, Jong Seong,Giesy, John P. Springer-Verlag 2015 Environmental geochemistry and health Vol.37 No.3

Structural Damage Detection using Deep Convolutional Neural Network and Transfer Learning

Chuncheng Feng,Hua Zhang,Shuang Wang,Yonglong Li,Haoran Wang,Fei Yan 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.10

During the long-term operation of hydro-junction infrastructure, water flow erosion causes concrete surfaces to crack, resulting in seepage, spalling, and rebar exposure. To ensure infrastructure safety, detecting such damage is critical. We propose a highly accurate damage detection method using a deep convolutional neural network with transfer learning. First, we collectedimages from hydro-junction infrastructure using a high-definition camera. Second, we preprocessed the images using an imageexpansion method. Finally, we modified the structure of Inception-v3 and trained the network using transfer learning to detectdamage. The experiments show that the accuracy of the proposed damage detection method is 96.8%, considerably higher thanthe accuracy of a support vector machine. The results demonstrate that our damage detection method achieves better damagedetection performance.