Prediction of flow boiling heat transfer coefficient in horizontal channels varying from conventional to small-diameter scales by genetic neural network

Jing Zhang,Yichao Ma,Mingjun Wang,Dalin Zhang,Suizheng Qiu,Wenxi Tian,Guanghui Su 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.8

Three-layer back propagation network (BPN) and genetic neural network (GNN) were developed in this study to predict the flow boiling heat transfer coefficient (HTC) in conventional and small-diameter channels. The GNN has higher precision than BPN (with root mean square errors of 17.16% and 20.50%, respectively) and other correlations. The inputs include vapor quality x, mass flux G, heat flux q, diameter D and physical parameter φ, and the predicted flow boiling HTC is set as the outputs. Influences of input parameters on the flow boiling HTC are discussed based on the trained GNN: nucleate boiling promoted by a larger saturated pressure, a larger heat flux and a smaller diameter is dominant in small channels; convective boiling improved by a larger mass flux and a larger vapor quality is more significant in conventional channels. The HTC increases with pressure both in conventional and small channels. The HTC in conventional channels rises when mass flux increases but remains almost unaffected in small channels. A larger heat flux leads to the HTC growth in small channels and an increase of HTC was observed in conventional channels at a higher vapor quality. HTC increases inversely with diameter before dry out.

Production of diacylglycerols by esterification of oleic acid with glycerol catalyzed by diatomite loaded SO4 2-/TiO2

Zhen Zhang,Hui Hua Huang,Xiang Ma,Guanghui Li,Yong Wang,Guo Sun,Yinglai Teng,Rian Yan,Ning Zhang,AiJun Li 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.53 No.-

A new and efficient technique is described for the production of diacylglycerols (DAGs) by the esterification of oleic acid with glycerol catalyzed by diatomite-loaded SO4 2/TiO2. DAGs show some potential health benefits compared to triacylglycerols, and also can be used to produce the novel industrial plasticizer epoxy fatty acid methyl ester in material science. Diatomite-loaded SO4 2/TiO2 catalyst was prepared and characterized, and the selected conditions for the synthesis of DAGs were determined to be: reaction time = 6.0 h, temperature = 210 C, catalyst loading = 0.1% of the oleic acid weight, and mass ratio of oleic acid to glycerol = 2:1. Under these conditions, DAGs yield reached 59.6% with a purity of 69.6% after a one-stage molecular distillation. Diatomite-loaded SO4 2/TiO2 as a solid catalyst could be recycled and reused with high catalytic efficiency. Under the same conditions, diatomite-loaded SO4 2/TiO2 showed a better catalytic performance than the commercial solid acid SO4 2/ZrO2-Al2O3. Based on this, a two-step reaction method for the production of DAGs was performed and provided a yield similar to the one-step method (58.3% vs. 59.6%), but with a shorter reaction time (4 h vs. 6 h). It is concluded that a two-step reaction method could be a better alternative to the one-step production of DAGs in the presence of diatomite-loaded SO4 2/TiO2.

Quantum Chaotic Image Encryption with One Time Running Key

Cao Guanghui,Zhou Jun,Zhang Yizhi,Jiang Yueling,Zhang Xing 보안공학연구지원센터 2014 International Journal of Security and Its Applicat Vol.8 No.4

明代的“律贖”

張光輝(Guanghui-Zhang) 경북대학교 아시아연구소 2009 아시아연구 Vol.- No.5

소위 贖刑이라는 것은, 죄인이 재물, 노역 혹은 관직으로 과해진 형벌을 면하는 것이다. 속형은 중국전통사회에서 매우 빨리 출현하였는데, 유학자들은 하상시기부터 시작되었다고 보거나, 서주시기에서 시작되었다고 보는 등 학자에 따라 그 견해가 다르지만, 속형은 일종의 제도로써 진시기에 성립되어 만들어 졌다는 것에는 이견이 없다. 진 이후 한, 당, 송, 원, 명, 청 각 시기의 속형제도는 비록 같지 않았으나, 이러한 조항제도는 쇠퇴하지 않고 계승되어 청말까지 이어져 '大清新刑律'이 완성되고서야 폐지되었지만, 속형제도는 중국고대법제 중 중요한 위치를 차지하고 있었다고 볼 수 있다. 명조속형의 실시는 이전보다 왕조가 더욱 광범위하고, 제도가 완비되며, 또한 많은 혁신한 부분이 있어, 명 한 시기의 법제 중 하나의 큰 특징이 된다. 명대의 속형제도는 大明律의 “律贖”와 역대왕조에서 반포한 鄭 “贖例”의 “例贖”, 두 부류로 나누어진다. “例贖”는 유연하고 잘 바뀌어서, 적용할 수 있는 대상이 매우 넓어서, 실제적인 정부의 필요에 따르는 일이 많았기에, 혹 재물, 예를 들어 쌀을 납속하거나, 말을 납속하거나, 여물, 벽돌 등을 받기도 하고, 혹은 노역으로 취해 대신하고, 무게는 재정적 실용을 보충하고, 사정이 대단히 복잡해서, 학계는 이러한 점에 대해서 관심을 기울이고 있다. “律贖”은, 명률을 홍무말년 부터 고정시킨 이후부터 명대 끝까지 변하지 않았고, 미미한 관련만이 있었다. 명대 “律贖”은 형벌을 신중히 하였고, 그 적용대상을 단지 노인과 아이, 신체장애자, 부녀 등에만 한정하였다. 그러나 재물의 수효가 “例贖”보다 아득하게 낮아서, 명대 속형제도의 양조를 병행하는 방식의 하나가 되었다. “律贖”의 법률은 大明律에 의거한 것이다. 大明律은 태조 주원장 재위하던 홍무시기에 완성되어, 홍무년간에 四部大明律, 즉 홍무7년률(1374), 홍무9년률(1386), 홍무22년률(1389)과 홍무30년률(1397)이 모두 제정되었으며, 속형내용을 구체화하여 차이가 있었다. 홍무 30년에 정해진 大明律은, 명초법률실천의 총결이자, 조훈적 성질을 갖추고 있으며, 주원장이 후사를 정하여도 변화가 없었다. 大明律로 인하여 법률에 의거한 “律贖”은 상대적으 로 온정성을 가지고 있어서, 우리들이 고찰하기 편하다. 하지만, 홍무시기의 전, 지폐, 은의 통용으로 말미암아, 차후 寶鈔이 큰 폭으로 값어치가 낮아져서, 律贖등을 조훈을 지키는 전제하에 이용하고, 특히 그 명중후기의 백은이 화폐로 유통되는 현실 하에서, 그에 상응하는 변화를 가져올 수밖에 없었다. 그래서 본문 머리말에는 홍무 30년의 大明律과 律解辨疑를 비교하고, 大明律直解소재의 홍무의 다른 시기에 완성된 大明律의 속형내용을 비교하여, “律贖”의 발전과정을 해명 한다. 그리고 나서 홍무 30년 大明律에 의거하여, “律贖”의 범죄, 주체, 형벌, 律贖의 내용, 律贖의 방식 등의 적용을 분석한다. “律贖”제도에 대해서 분석을 하는 동시에, 구체적 안건을 통해 사법 실천 중 律贖의 구체적인 실시 정황과 그 실시효과를 고찰하겠다. 그러한 후에 명대 화폐체계의 연혁을 통하여 “律贖”방식을 따라 납속된 동, 동전, 지폐, 은의 전환과 그 원인 등을 고찰하고, 동시에 “例贖”등 칙의 대조를 통하여, 지폐의 가치가 떨어지는 명대 사회형세변화와, “律贖”방식이 은의 전환으로 향하는 정황 하에서, “律贖” 등은 처음부터 끝까지 비교적 낮게 유지되어 휼형목적을 달성했다는 것을 밝힌다. Expiation of penalty means that one can expiates or atone a crime with property, penal servitude, or official position. The system of Expiation of penalty likely came into being in Xia-Shang dynasty, or West-Zhou dynasty, even Qin dynasty of China. Scholars’ opinions differ from each other. After the Qin dynasty, this system, which may had similarities and differences, was carried on in Han, Tang, Song, Yuan, Ming and Qing dynasty, Until the late Qing Dynasty when The new criminal law of Qing was enacted. So it played an important role in ancient China’s legal system. In Ming dynasty, the system of expiation of penalty, which came into maturity, and had many innovation, was put in practice more extensive than ever before. It was not only affected all levels of society of Ming dynasty, but also the society of Ming dynasty for many hundreds of years, because it was inherited mostly by the latter. So we can say that the system is of great significance. This paper makes a comprehensive and systematic study on it. The system of expiation of penalty in Ming dynasty can be divided into two parts, one was according to Daming law, and another was according to statutes promulgated in reigning of many emperors of Ming dynasty. This paper emphasizes particularly on the former. Daming law was emended in reigning of Yuanzhang-Zhu, the first emperor of Ming dynasty. In reigning of Yuanzhang-Zhu, four Daming laws were promulgated respectively in the years or 1374, 1376, 1389, and 1397. The Daming laws promulgated in 1397 was the summary of legal practice of the early Ming dynasty. It was the ancestor’s prescript which must be abided by the latter emperors. So the system of expiation of penalty according to Daming law promulgated in 1397 of Ming dynasty was relatively fixed, and can be studied easily. In this paper, the recordation of expiation of penalty of three Daminhg law, which was embodied respectively in the Daming laws promulgated in 1397, “Law of Discrimination”, and “Minglv straight solution”, was compared firstly. Then, according to Daming law promulgated in 1397, provisions of the offence, the main penalty, content, method, etc. applied the expiation system, were analyzed. In the analysis of the system, Investigation of specific cases to judicial practice in the implementation of the expiation of penalty was carried on. Thirdly, thinking over the evolution of the monetary system in Ming Dynasty, the reason why the method of expiation of penalty changed from paying coins, bill, and silver, and so on.

Active control of amplitude and phase of high-power RF systems in EAST ICRF heating experiments

Zhu Guanghui,Liu Lunan,Mao Yuzhou,Zhang Xinjun,Guo Yaoyao,Ai Lin,Jiang Runhao,Qin Chengming,Zhang Wei,Yang Hua,Yuan Shuai,Wang Lei,Ju Songqing,Wang Yongsheng,Sun Xuan,Yang Zhida,Wang Jinxin,Cheng Yan 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.2

The EAST ICRF system operating space has been extended in power and phase control with a low-level RF system for the new double-strap antenna. Then the multi-step power and periodic phase scanning experiment were conducted in L-mode plasma, respectively. In the power scanning experiment, the stored energy, radiation power, plasma impedance and the antenna's temperature all have positive responses during the short ramp-ups of PL;ICRF. The core ion temperature increased from 1 keV to 1.5 keV and the core heating area expanded from jZj 5 cmto jZj 10 cm during the injection of ICRF waves. In the phasing scanning experiment, in addition to the same conclusions as the previous relatively phasing scanning experiment, the superposition effect of the fluctuation of stored energy, radiation power and neutron yield caused by phasing change with dual antenna, resulting in the amplitude and phase shift, was also observed. The active control of RF output facilitates the precise control of plasma profiles and greatly benefits future experimental exploration.

Injuries Analysis of Rear Row Occupants Exposed to Vehicle’s Frontal Oblique Collision

Zhou Hua,Liao Jingqian,Zhang Qiaoyu,Zhang Guanghui,Zhang Daowen 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.3

This paper discusses the rear left-hand occupant’s injury during frontal oblique collision with PRESYS software. Based on the simulations among different frontal oblique angles (10 ~ 50 °) and occupant constraint system models, the injury of rear left-hand dummy are analyzed at an initial collision speed of 50 km/h. It is found that the impact on the occupant’s dynamic responses (acceleration and shear forces) by the seat belt is significant and depends upon the oblique angle. With the given vehicle and collision speed, it is observed that the seat belt can effectively reduce the occupant’s head acceleration and the neck longitudinal (Fx) shear force if the collision angle is between 10 ° and 20 °. However, the seat belt increases the occupant’s head resultant acceleration when the collision angle is between 35 ° and 40 °. In addition, when the collision angle is between 10 ° and 50 °, the seat belt can also effectively reduce the occupant\'s chest acceleration. At most collision angles, the seat belt can effectively reduce the overall damage of rear row left occupant in frontal oblique collision, but the WIC (Weighted Injury Criterion) value of the rear row dummy with seat belt is still very large at the collision angle below 30 °. Therefore, the restraint system of the rear row occupants needs to be improved.

Ontology-Based Cutting Tool Configuration Considering Carbon Emissions

Guanghui Zhou,Qi Lu,Zhongdong Xiao,Ce Zhou,Shengze Yuan,Chao Zhang 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.11

In order to improve the precision and efficiency of cutting tool configuration and reduce carbon emissions during manufacturing process, an ontology-based cutting tool configuration process considering carbon emissions is put forward in the paper. Firstly, the architecture of ontology-based cutting tool configuration is established and key functional modules are described. Secondly, ontology is applied to describe the complex knowledge of cutting tool configuration and the Semantic Web Rule Language (SWRL) is used to build inference rules to reason feasible cutting tool configuration schemes according to machining requirements. Thirdly, taking carbon emissions as the objective, an evaluation method based on the c-PBOM-T (carbon emissions-Process Bill of Material for cutting Tools) table is studied to decide an optimal cutting tool configuration scheme from the feasible ones in the previous step for part machining. Finally, the proposed method is applied to a vortex shell workpiece to demonstrate its feasibility. The results show that the proposed method can improve the cutting tool configuration and reduce carbon emissions effectively for the machining processes. The presented method provides a valuable insight into the intelligent cutting tool configuration to support low-carbon manufacturing.

Characterisation of Shear Creep and Stress Relaxation of Serrate Discontinuity in Rock Mass under Different Loading Paths

Guanghui Tian,Yadong Bian,Qingzhao Zhang,Chunqing Li,Yuxi Hao 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.4

In engineering applications, rocks rarely exist in their monolithic form and discontinuities always occur in the rocks. Intuitively there is a considerable difference in rheological properties between monolithic rocks and rocks with discontinuities. The present paper aims to characterise the shear creep and stress relaxation of serrate discontinuity in rock mass under different loading paths. A comprehensive experimental program, including creep tests, stress relaxation tests and unloading tests, on serrate discontinuities, is developed with focus on the effect of the slope angle of the serrated surface of the discontinuity on its creep and stress relaxation. Empirical models for shear creep and stress relaxation are also developed. We found in the paper that the larger the slope angle of a discontinuity is the larger both the creep and stress relaxation are, and the stress-strain relation of discontinuities in rock masses can be different under different loading paths. The significance of the research is that it investigates the simultaneous shear creep and stress relaxation of a serrate discontinuity under various loading paths. The paper concludes that the empirical models for creep and stress relaxation developed in the paper can help geotechnical engineers to analyse and assess the behaviour of rock masses with discontinuities.

Optimistic Fault Diagnosis in Discrete Event Systems by Labeled Petri Nets and Basis Markings

Guanghui Zhu,Jiafeng Zhang,Zhong Zheng,Shan Luan,Te Chen,Qiang Ma,Zhiwu Li 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.6

This paper deals with the fault diagnosis problem of discrete event systems modeled with labeled Petri nets. Its main contributions are threefold. First, depending on whether a diagnosis function examines the fault transitions that possibly occur after the last observed event, we formally divide the diagnosis functions into two types: optimistic and pessimistic, which aims to facilitate the exploration of different diagnosis approaches. Second, a framework is proposed, which extends a given diagnosis approach for Petri nets to the case of labeled Petri nets. The main idea of the framework is to compute and combine the diagnosis results of observable transition sequences corresponding to an observed word. Third, we convert a basis-marking-based approach that is originally pessimistic to the optimistic case and prove the correctness of this conversion.

Fuzzy Approximation-Based Backstepping Control of Permanent Magnet Synchronous Motor

Zhang Yufeng,Yan Qi,Huang Nan,Wu Zihui,Gong Hao,Du Guanghui 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

A permanent magnet synchronous motor(PMSM) control system based on backstepping control can effectively improve the dynamic performance, and the design process is simple and easy to be implemented in engineering. However, factors such as changes in motor parameters due to environmental changes, wear and aging, and external load disturbances can adversely affect the control system, resulting in degraded control performance. To address this problem, this paper proposes a fuzzy approximation-based backstepping control method for PMSM. The method constructs a mathematical model containing the perturbation term of the PMSM body parameters and the load disturbance term. And the universal approximation property of the fuzzy logic system is used to approximate the disturbance terms in the model, based on which a backstepping controller satisfying the stability requirements is designed. Finally, the simulation and experiment are given, which compare with the traditional backstepping method. The results show that the proposed method can effectively suppress the adverse effects of motor parameter changes and load disturbances on the motor control system.