Integrated expression and general optimisation method of bucket shape line of backhoe hydraulic excavator

Haoran Sun,Zhigui Ren,Junli Wang,Weifeng Wei,Yongyong Liang,Minghao Feng 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6

The bucket shape of a hydraulic excavator influences its excavating performance and is determined by its shape line. In this study, the inner surface line projected on the symmetrical plane of the bucket was adopted as the bucket shape line, and the value ranges of the main parameters for the shape line were investigated. By considering the centre of the arc at the bucket bottom as the origin, the Cartesian coordinate system was established, and the integrated equation of the bucket line was derived based on the geometric constraints related to the shape line. A general optimisation model of the bucket line was established using the integrated equation. The effects of four design variables on the optimisation goal were determined using the bucket of a 21 T excavator as an example, and the optimal shape line of the bucket was obtained using a genetic algorithm. The results indicated that the cutting angle decreased by 9.92 % in comparison with that before optimisation, which was beneficial in decreasing the digging resistance. Additionally, the aspect ratio decreased by 5.75 %, thereby reducing the bucket weight. Thus, the integrated expression and the optimisation of shape lines provide a general method and theoretical basis for optimising the bucket shape.

以“内卷”思想解读中国武术拳种与流派精细化产生的机制

Sun Haoran,이호근 한양대학교(ERICA캠퍼스) 한국미래문화연구소 2023 미래문화 Vol.0 No.6

The literature method and the logical analysis method are used to interpret the "involution" of the production of Chinese martial arts styles and schools, and to analyze the possibility mechanisms inherent in Chinese martial arts. It is argued that: the internal volume of martial arts promotes the refined production of schools, and the internal volume of basic movements, combined movements, and characteristic techniques play different roles in the refined production of schools; the internal volume of martial arts contributes to the refined production of schools, and provides the basis for the refined production of different styles of martial arts from three different dimensions: micro, meso, and macro; the internal volume way of thinking creates the cultural wonders of Chinese martial arts. The "fine cultivation" and "over-dense growth" of the internal volume thought and the positive and negative application of the internal volume thought make the sustainable development of Chinese martial arts' styles and schools possible.

IL-33 Promotes ST2-Dependent Fibroblast Maturation via P38 and TGF-β in a Mouse Model of Epidural Fibrosis

Wang Haoran,Wu Tao,Hua Feng,Sun Jinpeng,Bai Yunfeng,Wang Weishun,Liu Jun,Zhang Mingshun 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.3

BACKGROUND: Recent evidence suggests that IL-33, a novel member of the IL-1b family, is involved in organ fibrosis. However, the roles of IL-33 and its receptor ST2 in epidural fibrosis post spine operation remain elusive. METHODS: A mouse model of epidural fibrosis was established after laminectomy. IL-33 in the wound tissues post laminectomy was measured with Western blotting, ELISA and immunoflurosence imaging. The fibroblast cell line NIH- 3T3 and primary fibroblasts were treated with IL-33 and the mechanisms of maturation of fibroblasts into myofibroblasts were analyzed. To explore roles of IL-33 and its receptor ST2 in vivo, IL-33 knockout (KO) and ST2 KO mice were employed to construct the model of laminectomy. The epidural fibrosis was evaluated using H&E and Masson staining, western-blotting, ELISA and immunohistochemistry. RESULTS: As demonstrated in western blotting and ELISA, IL-33 was increased in epidural wound tissues post laminectomy. The immunoflurosence imaging revealed that endothelial cells (CD31?) and fibroblasts (a-SAM?) were major producers of IL-33 in the epidural wound tissues. In vitro, IL-33 promoted fibroblast maturation, which was blocked by ST2 neutralization antibody, suggesting that IL-33-promoted-fibroblasts maturation was ST2 dependent. Further, IL-33/ ST2 activated MAPK p38 and TGF-b pathways. Either p38 inhibitor or TGF-b inhibitor decreased fibronectin and a-SAM production from IL-33-treated fibroblasts, suggesting that p38 and TGF-b were involved with IL-33/ST2 signal pathways in the fibroblasts maturation. In vivo, IL-33 KO or ST2 KO decreased fibronectin, a-SMA and collagen deposition in the wound tissues of mice that underwent spine surgery. In addition, TGF-b1 was decreased in IL-33 KO or ST2 KO epidural wound tissues. CONCLUSION: In summary, IL-33/ST2 promoted fibroblast differentiation into myofibroblasts via MAPK p38 and TGFb in a mouse model of epidural fibrosis after laminectomy.

Research on Recognition Method of Electrical Components Based on FEYOLOv4-tiny

Gao Jilong,Sun Haoran,Han Jiarui,Sun Qian,Zhong Tie 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.6

Recently, electrical component recognition technology is of great signifi cance for fault identifi cation and stable operation of the modern power grids. With the rapid improvement of smart grids, higher requirements are put forward to the recognition methods in detection accuracy and real-time performance. However, the conventional recognition methods are fail to meet the demands since they always have drawbacks in detection performance. To improve the electrical component identifi cation capability, a novel detection method based on Feature Enhanced You Only Look Once v4-tiny (FEYOLOv4-tiny) is proposed in this study. Here, YOLOv4-tiny is employed as the prototype of the proposed network, whereas enhancement module is designed to improve the feature extraction capability. Moreover, frequency channel attention and spatial attention module are utilized to capture the informative and discriminatory features. Experimental results indicate that our proposed method outperforms other lightweight networks in detection accuracy with almost the same real-time performance, especially for the small targets with complex background. Over all, FEYOLO v4-tiny is effi cient in electrical component identifi cation and has signifi cant application prospects in power inspection.

SYNTHESIS AND PROPERTY OF MULTIFUNCTIONAL Fe3O4@SiO2@CeO2@Au COMPOSITE MICROSPHERES

YANG WANG,HAORAN SUN,TONG ZHANG,ANJIAN XIE 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2012 NANO Vol.7 No.6

In this paper, Fe3O4@SiO2@CeO2@Au core/shell microspheres were synthesized through hydrolysis and solvothermal processes. The results indicated that the magnetic Fe3O4 cores were well wrapped by the coating layer of SiO2/CeO2 with a thickness of 50 nm, and Au nanoparticles with 35 nm in diameter were attached on the shell. The microspheres showed a monodispersity and superparamagnetism. The composites showed excellent ability to absorb a wide range of wavelengths including visible and NIR region (from 250 nm to 800nm), making it a potential full solar spectrum response photocatalyst for sunlight applications.

Experimental Investigation on the Properties of Sustainable Pervious Concrete with Different Aggregate Gradation

Junyu Zhang,Haoran Sun,Xiaotian Shui,Wenxuan Chen 한국콘크리트학회 2024 International Journal of Concrete Structures and M Vol.18 No.2

Pervious concrete (PC) as a green infrastructure material has been increasingly used due to its positive environmental impacts, such as controlling storm water runoff, removing water pollutants and reducing heat island effect. The aggregate gradation is a critical factor influencing the physical properties of PC. Therefore, this paper represents an attempt to determine the effects of aggregate gradation on the various physical properties of PC, and then to explore relationships between them. To this end, three aggregate gradations 4.75–9.5 mm, 9.5–19 mm and 19–31.5 mm were recombined with various proportions (20–80%) to obtain five different gradations named as A, B, C, D and E. PC mixtures were prepared with these five aggregate gradations. Then, physical and mechanical properties of PC including porosity, permeability, compressive strength and water stability were investigated, according to the available specification. The results suggested that it was feasible to use waste concrete for permeable pavement, because all the specimens provided required specification requirements. Different linear relationships were also found between the maximum aggregate size and porosity, permeability coefficient, compressive strength and its loss rate. That is, porosity and permeability increased with the proportion of larger size aggregate increased, however, compressive strength reduced. Thus the compressive strength had an inverse correlation with the porosity and water permeability. Among five different aggregate gradations, group C (20% of 4.75–9.5 mm aggregate, 50% of 9.5–19 mm aggregate and 30% of 19–31.5 mm aggregate) can be seen as the optimum gradation and is suitable for base layer materials of permeable pavements.

Exosomes derived from miR-214-3p overexpressing mesenchymal stem cells promote myocardial repair

Wenwu Zhu,Qingjie Wang,Jian Zhang,Ling Sun,Xiu Hong,Wei Du,Rui Duan,Jianguang Jiang,Yuan Ji,Haoran Wang,Bing Han 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Aims Exosomes are known as nanovesicles that are naturally secreted, playing an essential role in stem-mediated cardioprotection. This study mainly focused on investigating if exosomes derived from miR-214 overexpressing mesenchymal stem cells (MSCs) show more valid cardioprotective ability in a rat model of acute myocardial infarction (AMI) and its potential mechanisms. Methods Exosomes were isolated from control MSCs (Ctrl-Exo) and miR-214 overexpressing MSCs (miR-214OE-Exo) and then they were delivered to cardiomyocytes and endothelial cells in vitro under hypoxia and serum deprivation (H/SD) condition or in vivo in an acutely infarcted Sprague-Dawley rat heart. Regulated genes and signal pathways by miR-214OE-Exo treatment were explored using western blot analysis and luciferase assay. Results in vitro , miR-214OE-Exo enhanced migration, tube-like formation in endothelial cells. In addition, miR-214OE-Exo ameliorated the survival of cardiomyocytes under H/SD. In the rat AMI model, compared to Ctrl-Exo, miR-214OE-Exo reduced myocardial apoptosis, and therefore reduced infarct size and improved cardiac function. Besides, miR-214OE-Exo accelerated angiogenesis in peri-infarct region. Mechanistically, we identified that exosomal miR-214-3p promoted cardiac repair via targeting PTEN and activating p-AKT signal pathway. Conclusion Exosomes derived from miR-214 overexpressing MSCs have greatly strengthened the therapeutic efficacy for treatment of AMI by promoting cardiomyocyte survival and endothelial cell function.

Exploring cognitive trajectories and their association with physical performance: evidence from the China Health and Retirement Longitudinal Study

Jingdong Suo,Xianlei Shen,Jinyu He,Haoran Sun,Yu Shi,Rongxin He,Xiao Zhang,Xijie Wang,Yuandi Xi,Wannian Liang 한국역학회 2023 Epidemiology and Health Vol.45 No.-

OBJECTIVES: The long-term trends of cognitive function and its associations with physical performance remain unclear, particularly in Asian populations. The study objectives were to determine cognitive trajectories in middle-aged and elderly Chinese individuals, as well as to examine differences in physical performance across cognitive trajectory groups. METHODS: Data were extracted from the China Health and Retirement Longitudinal Study. A total of 5,701 participants (47.7% male) with a mean age of 57.8 (standard deviation, 8.4) years at enrollment were included. A group-based trajectory model was used to identify cognitive trajectory groups for each sex. Grip strength, repeated chair stand, and standing balance tests were used to evaluate physical performance. An ordered logistic regression model was employed to analyze differences in physical performance across cognitive trajectory groups. RESULTS: Three cognitive trajectory groups were identified for each sex: low, middle, and high. For both sexes, higher cognitive trajectory groups exhibited smaller declines with age. In the fully adjusted model, relative to the low trajectory group, the odds ratios (ORs) of better physical performance in the middle cognitive group were 1.37 (95% confidence interval [CI], 1.17 to 1.59; p<0.001) during follow-up and 1.40 (95% CI, 1.20 to 1.64; p<0.001) at the endpoint. The ORs in the high trajectory group were 1.94 (95% CI, 1.61 to 2.32; p<0.001) during follow-up and 2.04 (95% CI, 1.69 to 2.45; p<0.001) at the endpoint. CONCLUSIONS: Cognitive function was better preserved in male participants and individuals with higher baseline cognitive function. A higher cognitive trajectory was associated with better physical performance over time.

Stress sensitivity in naturally fractured reservoirs: a case study of the Lower Cretaceous Xiagou Formation, Qingxi Oilfield, Jiuxi Basin, northwestern China

Wei Ju,Xiaolong Fu,Weifeng Sun,Haoran Xu,Shengyu Wang 한국지질과학협의회 2020 Geosciences Journal Vol.24 No.3

Stress sensitivity is the variation of rock petrophysical parameters resulting from changes in effective stress. In fractured reservoirs, experimental methods exhibit a certain amount of error in the quantitative analysis of reservoir rock stress sensitivity. In addition, fracture-bearing experimental rock samples are difficult to obtain and prepare. Therefore, in the present study, reservoir rock stress sensitivity in naturally fractured reservoirs was investigated based on geomechanical modeling using a case study of the Lower Cretaceous Xiagou Formation in the Qingxi Oilfield. The results indicate that the Xiagou fractured reservoir experiences strong stress sensitivity with a fracture permeability damage rate reaching 94.38%. Natural fractures influence reservoir rock stress sensitivity. The degree of filling and type of filled minerals within natural fractures have great effects on the permeability damage rate. A higher permeability damage rate suggests stronger rock stress sensitivity. Generally, I) for reservoir rocks with unfilled natural fractures, the permeability damage rate is extremely high; II) for reservoir rocks with partially filled natural fractures, the permeability damage rate is high, and if the minerals within the natural fractures are insoluble, the permeability damage rate is slightly higher than if the materials are soluble; III) for reservoir rocks with completely filled natural fractures, the permeability damage rate is extremely low if the minerals within the natural fractures are insoluble; however, if the materials are soluble, the permeability becomes slightly higher with the increase of effective stress. Most importantly, this study provides a practical method for analyzing stress sensitivity in naturally fractured reservoirs.

개인용 클라우드 컴퓨팅 서비스 수용의도에 영향을 미치는 요인 : 중국 사례

김수현(Soo-Hyun Kim),손호연(Haoran Sun) 한국콘텐츠학회 2013 한국콘텐츠학회논문지 Vol.13 No.11

클라우드 컴퓨팅 서비스는 세계적으로 빠르게 성장하고 있으며, 중국에서도 바이두를 중심으로 개인용클라우드 컴퓨팅 서비스가 비약적으로 발전하고 있다. 새로운 서비스가 등장하는 경우 서비스 수용 요인이 무엇인지에 대한 연구는 매우 중요하게 다루어지고 있다. 본 논문에서는 중국의 개인용 클라우드 컴퓨팅 서비스 사용자를 대상으로 개인용 클라우드 컴퓨팅 서비스 수용에 영향을 주는 요인을 분석하고자 한다. 이를 위해 기술수용모형을 토대로 프라이버시, 정보활용욕구, 서비스 유형, 서비스 적절성, 시스템 품질, 시스템 보안 등의 연구변수를 포함하여 확장한 연구모형을 설계하였고, 설계한 연구모형은 구조방정식모형을 사용하여 실증하였다. 검증결과에 의하면, 프라이버시, 서비스 적절성, 시스템 품질, 시스템 보안 등의 요인은 유용성과 사용용이성에 영향을 주며 결국에는 서비스 수용의도에 긍정적인 영향을 미치는 것으로 나타났다. 반면, 정보활용 욕구와 서비스 유형은 유용성과 사용용이성 모두에 유의한 영향을 미치지 않는 것을 확인할 수 있다. As the Cloud Computing services are growing fast in the world, the number of Cloud Computing service users are being increased enormously in China. Studies on Intention-to-Use have been one of the interesting topics in the field of marketing. In this paper we investigate the factors influencing the intention-to-use of Cloud Computing services in China. Our research model is based on Technology Acceptance Model and includes ‘privacy’, ‘information needs’, ‘service types’, ‘service appropriation’, ‘system quality’, and ‘system security’. We surveys the Chinese Cloud Computing service users and analyzes with Structural Equation Model. The results show that ‘privacy’, ‘service appropriation’, ‘system quality’, and ‘system security’ give positive effects to ‘intention-to-use’. However, ‘information needs’ and ‘service types’ does not give positive effects.