Point Cloud 3D Weldment Reconstruction and Welding Feature Extraction for Robotic Multi-bead Arc Weld Cladding Path Plaanning

Wenhui Wang,Wang Zhang,Xiyang Liu,Xu Zhang,Weiqiang Huang,Zejian Deng 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.25 No.5

Traditional manual teaching or offline programming welding modes may lead to long teaching time, low efficiency, and inability to adapt to changing welding environments when facing complex trajectory workpieces or Multi-welded workpieces. In this paper, a teaching-free welding method based on visual sensing system for robotic is proposed. Firstly, the three-dimensional information of the workpiece surface is captured by a monocular structured light camera and characterized by point cloud data. Point cloud stitching is performed on multiple local images of large-size workpieces to reconstruct the welding surface. Then, statistical filtering and deep learning methods are used to preprocess and segment the point cloud to obtain the reference points of the welding path. Finally, according to the shape characteristics of the workpiece, the auxiliary projection method is used to automatically generate the robot surfacing path. Experimental results show that under the condition of camera accuracy of ± 0.05 mm, the maximum planning path error is less than 1 mm, which meets the actual welding needs. This method is significant for achieving welding automation and improving production efficiency.

Decreased Insulin Resistance by Myo-Inositol Is Associated with Suppressed Interleukin 6/Phospho-STAT3 Signaling in a Rat Polycystic Ovary Syndrome Model

Yulong Zhang,Changzhong Li,Wenhui Zhang,Xiangqin Zheng,Xiujuan Chen 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.4

Myo-inositol supplementation may reduce insulin resistance (IR) with few serious side effects in patients with polycystic ovary syndrome (PCOS). To explore the mechanism of this action in an animal model, a PCOS-IR rat model was generated. Enzyme-linked immunosorbent assay was used to assess changes in ovulation function during treatment with a myo-inositol supplement, and Western blotting, real-time polymerase chain reaction, and immunohistochemistry were performed to investigate the underlying molecular mechanisms. The results showed that the myo-inositol supplement decreased the homeostatic model assessment of insulin resistance (HOMA-IR) index and significantly decreased the serum levels of luteinizing hormone (LH), LH/follicle-stimulating hormone ratio, and testosterone, while increasing the serum level of estradiol. Upregulation of interleukin 6 (IL-6), phospho-STAT3 (p-STAT3), Mir-21, and Mir-155 and significant downregulation of PPAR-γ and GLUT4 were detected in the untreated PCOS-IR rat model. However, downregulation of IL-6, p-STAT3, miR-21, and miR-155 and significant upregulation of PPAR-γ and GLUT4 were detected with myo-inositol supplementation. Thus, myo-inositol supplementation may reduce Mir-21 and Mir-155 levels by downregulating IL-6 and p-STAT3 and, subsequently, reverse the expression of PPAR-γ and GLUT4, leading to a decreased HOMA-IR index. In conclusion, the identification of an IL-6/p-STAT3/Mir-155/Mir-21/PPAR-γ/GLUT4 system in the PCOS-IR rat model provides insight into the pathogenesis of PCOS and may indicate a possible therapeutic strategy. Amelioration of the basal serum glucose levels and of the HOMA/HOMA-IR index may be achieved by the reversal of the expression of PPAR-γ and GLUT4 through the downregulation of IL-6, p-STAT3, miR-21, and miR-155 with myo-inositol supplementation.

The Effect of Surface Modifications on the Magnetic Properties of Ni<SUB>0.5</SUB>Zn<SUB>0.5</SUB>Fe₂O₄ Nanoparticles

Wei Zhang,Hongxia Wang,Faling Zhang,Zhengnan Qian,Wenhui Su 한국자기학회 2008 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

A Novel Material Fluorescence Probe Based on Covalently Functionalized Graphene Oxide by Aminocoumarin for Detection of CN-

Wenhui Ma,Zhaochuan Yu,Zhongcai Li,Jing Wen,Baoru Zhao,Yong Zhang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2020 NANO Vol.15 No.03

Owing to the hazardness, the sensitive and selective detection of cyanide (CN-) in water or water-containing systems has still been a puzzle plaguing scientists all around the world. In this paper, a novel fluorescence probe based on covalently functionalized graphene oxide (GO) by aminocoumarin for highly selective detection of CN- in deionized water was prepared under the action of EDC/NHS. This probe bears aminocoumarin group as the recognition site and fluorophore, and its fluorescence quantum yield is increased by 0.07. Simultaneously, by loading on GO, the dispersibility, selectivity and reversibility were soundly improved, which facilitated the detection process. The fluorescence spectra showed that the probe has high selectivity and sensitivity for cyanide, and has potential application in real water.

Evaluate Dry Deposition Velocity of the Nitrogen Oxides Using Noah-MP Physics Ensemble Simulations for the Dinghushan Forest, Southern China

Qi Zhang,Ming Chang,Shengzhen Zhou,Weihua Chen,Xuemei Wang,Wenhui Liao,Jianing Dai,ZhiYong Wu 한국기상학회 2017 Asia-Pacific Journal of Atmospheric Sciences Vol.53 No.4

There has been a rapid growth of reactive nitrogen (Nr) deposition over the world in the past decades. The Pearl River Delta region is one of the areas with high loading of nitrogen deposition. But there are still large uncertainties in the study of dry deposition because of its complex processes of physical chemistry and vegetation physiology. At present, the forest canopy parameterization scheme used in WRF-Chem model is a single-layer “big leaf” model, and the simulation of radiation transmission and energy balance in forest canopy is not detailed and accurate. Noah-MP land surface model (Noah-MP) is based on the Noah land surface model (Noah LSM) and has multiple parametric options to simulate the energy, momentum, and material interactions of the vegetation-soil-atmosphere system. Therefore, to investigate the improvement of the simulation results of WRF-Chem on the nitrogen deposition in forest area after coupled with Noah-MP model and to reduce the influence of meteorological simulation biases on the dry deposition velocity simulation, a dry deposition single-point model coupled by Noah- MP and the WRF-Chem dry deposition module (WDDM) was used to simulate the deposition velocity (Vd). The model was driven by the micro-meteorological observation of the Dinghushan Forest Ecosystem Location Station. And a series of numerical experiments were carried out to identify the key processes influencing the calculation of dry deposition velocity, and the effects of various surface physical and plant physiological processes on dry deposition were discussed. The model captured the observed Vd well, but still underestimated the Vd. The self-defect of Wesely scheme applied by WDDM, and the inaccuracy of built-in parameters in WDDM and input data for Noah-MP (e.g. LAI) were the key factors that cause the underestimation of Vd. Therefore, future work is needed to improve model mechanisms and parameterization.

Research on Model of Micro-grid Green Power Transaction Based on Blockchain Technology and Double Auction Mechanism

Zhao Wenhui,Zhang Shaochong,Xue Lei,Chang Tao,Wang Liao 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.1

The confict between climate change and energy scarcity has recently gained widespread attention. The development and promotion of green power and renewable energy is an efcient strategy to address this issue. The widespread use of distributed renewable energy in microgrids results in decentralized power supply. The features of distributed power trading, such as low single transaction volume and frequent transaction intervals, present both possibilities and problems to the green electricity market. The usual centralized control and selling of power are no longer appropriate in this circumstance. This study proposes a decentralized energy transaction system architecture in the microgrid and connects the double auction mechanism to achieve the interests of each participant based on blockchain technology and the status quo green power trade in China. Finally, using the trading strategy and model, this study constructs a real and operational energy trading platform, and simulated experiments demonstrate the dependability and efcacy of the proposed trading mechanism.

디지털 경제의 발전이 탄소 배출의 강도에 미치는 영향 - 중국의 성급(省级) 패널 데이터를 활용한 실증연구

마문혜(Wenhui Ma),진엽청(Yeqing Chen),장몽택(Mengze Zhang) 한국콘텐츠학회 2023 한국콘텐츠학회논문지 Vol.23 No.2

중국경제는 고품질의 발전 단계로 전향하였고, 탄소 감축은 이미 현재의 주요 목표가 되었으며, 디지털 경제는 경제의 녹색 발전을 추진하는 중요한 구동력이 되었다. 본 논문은 디지털 경제의 발전이 탄소 배출에 미치는 영향 메커니즘을 분석하고, 2011년부터 2019년까지 30개 성급의 패널 데이터 실증을 바탕으로 디지털경제 발전이 탄소 배출 강도에 미치는 영향 효과와 지역 이질성을 검증하였다. 데이터는 주로 〈중국 에너지 통계 연감〉, 〈중국 환경 통계 연감〉, 〈중국 인구 고용 통계 연감〉, 각 성 통계 연감 및 통계 공보(公报)에서 가져온 것이다. 연구 결과 디지털 경제는 탄소 배출의 강도를 유의하게 낮췄으며, 이는 도구 변수를 인용하고 핵심 해석 변수를 대체하는 등의 강건성 검증 후에도 여전히 성립된다. 지역 이질성 측면에서 중국 동부지역의 디지털 경제 발전은 탄소 배출 강도에 뚜렷한 억제 작용을 하지만 이 작용은 중국 서부와 동북부 지역에서는 뚜렷하지 않다. 이상의 결론을 바탕으로 본 논문은 기초시설개발을 강화하고, 디지털 경제에 탄소 배출 감소 능력을 부여하는 특별 조치를 전개하며, 차별화된 디지털 경제 발전 전략을 실시하는 등의 방면에서 이에 상응하는 대책과 건의를 제기하였다. China’s economy has shifted to a stage of high-quality development, and carbon emission reduction has become a major goal at this stage. Digital economy has also become an important driving force for green economic development. The digital economy is an important driving force for carbon emission reduction. This paper analyzes the impact mechanism of digital economy development on carbon emissions, and empirically tests the impact of digital economy development on carbon emissions intensity and regional heterogeneity based on 30 provincial panel data from 2011 to 2019. The study found that the digital economy significantly reduced carbon emission intensity, and this conclusion still holds after robustness tests such as citing instrumental variables and replacing core explanatory variables; in terms of regional heterogeneity, the development of digital economy in central and eastern China has a significant impact on carbon emission intensity. A significant inhibitory effect was observed, but the effect was not significant in the western-northeast region of China. Based on the above conclusions, this paper puts forward corresponding countermeasures and suggestions from the aspects of strengthening infrastructure construction, carrying out special actions to empower carbon emission reduction through digital economy, and implementing differentiated digital economy development strategies.

Machine Health-Driven Dynamic Scheduling of Hybrid Jobs for Flexible Manufacturing Shop

Leilei Yin,Wenhui Zhang,Tong Zhou 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.5

In the multi-type & small batch production mode, jobs of small quantity (i.e., hybrid jobs) are implemented in the job shop. The production scheduling is a significant activity and it is necessary to predict the disturbance in advance. Some methods and tools to tackle the production scheduling have been provided. From the perspective of duration, our work extends the method of dynamic scheduling with incorporation of machine health prediction. The primary result of this work is the efficient generation of feasible scheduling solution when the machine health is warned. The machining quality data-based method is proposed to predict the machine health status and the relation between machine and quality characteristic is established. Combination of K-means, data equalization algorithm and particle swarm optimization (PSO) is designed to predict the machine health. Mathematical model in terms of duration is proposed and improved genetic algorithm (GA) is applied to generate the feasible scheduling solution. A prototype system is developed and a case study of a metalworking workshop is implemented. The results show that the work can reduce the risk of machine health to production. Using the prototype system, the engineers can filter out infeasible scheduling solutions automatically and acquire a successful one efficiently.

Research on the Amount of Empty Containers in Japanese Main Ports

Masayoshi,KUBO,Wenhui,ZHANG 한국항해항만학회 2004 한국항해항만학회 학술대회논문집 Vol.5 No.-

Economic development is remarkable in Asia and progress of industrialization of NIES, ASEAN, and China in East Asia has increased the international physical distribution in this area. However, an imbalance of trade becomes severe in these areas. The imbalance is especially big in the Asia-North America route and the Japan-China route. The imbalance in the Asia -North America liner route is 5.04 million TEUS in 2002. The transportation ratio of loaded containers between China and Japan route is approximately 3:1 in 2000. In other words, it means that the transportation of loaded containers from China to Japan is 3, the transportation of loaded containers from Japan to China is I. The imbalance at a port is generally obtained by subtracting export loaded container cargo volume from import container cargo volume. However, the imbalance and the empty containers at the port are not always same. Then, in order to evaluate rationalization and efficiency of maritime container transportation, we introduce the amount of empty containers at a port as an evaluation index. However, the past data of the amount of handling empty containers have a lot of lacking portions. Then, it is necessary to estimate the past amount of empty containers in order to grasp the amount of empty containers historically. So, we construct the mode that estimates the amount of empty containers using the imbalance of main port statistics in Japan.

Performance Analysis and Implementation of a PMIPv6-Based Partially Distributed Mobility Management

Ye Wang,Wenhui Zhang,Xiaobo Li,Feng Ling 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.7

This paper provides the implementation mechanism of the pmipv6-based partially distributed mobility management (DMM) and performs extensive simulations under various traffic environments for verification and evaluation of the proposed scheme. The simulation results indicated that Mobility Anchor and Access Router (MAAR) could distribute and manage all IP data packet flow between a corresponding node (CN) and mobile node (MN). Therefore, the implementation and performance analysis of proposed mechanism is essential to understand the fundamental features of DMM, which includes a method of detecting MN and managing MN’s location.