Assessment Method of Slope Excavation Quality based on Point Cloud Data

Zhiguo Pan,Yihong Zhou,Chunju Zhao,Chao Hu,Huawei Zhou,Yong Fan 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.3

Slope excavation quality assessment is essential in water conservancy engineering. This study presents a quality assessment method to estimate the excavation quality of a slope based on point cloud data obtained from a 3D Terrestrial Laser Scanner (TLS). A data processing method, which includes coordinate registration, data partitioning, and noise removal, is proposed to organize raw data from the TLS and ensure accurate and available point cloud data of a slope surface. An excavation quality assessment method with seven indicators, namely, slope ratio, slope toe elevation, back break, volume of back break, remained semi-void rate, unevenness, and offset degree, is proposed to analyze the difference between a slope’s as-design excavation appearance and actual construction appearance. The as-design excavation appearance is expressed by the Building Information Modeling (BIM) model of a slope-excavation face, and it is a reference to assess the actual construction appearance. The slope excavation quality of a water conservancy project in southwest China is evaluated with the proposed method and the traditional method. The results demonstratethat the proposed method can estimate the slope excavation quality effectively, rapidly, and accuately, and can provide theoretical data support for subsequent work.

Temperature Field Reconstruction of Concrete Dams based on Distributed Optical Fiber Monitoring Data

Huawei Zhou,Zhiguo Pan,Zhipeng Liang,Chunju Zhao,Yihong Zhou,Fang Wang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.5

Mastering the real temperature distribution of the concrete dam is the basis for solving the problem of temperature control and crack prevention. In this paper, Distributed Temperature Sensing (DTS) technology was applied to temperature monitoring of a higharch dam under construction in southwest China. In order to obtain a more comprehensive temperature distribution of the dam, optical fiber layout principles for arch dams were studied, and horizontal and vertical optical fiber layout schemes were first proposed according to these principles. The real temperature variation processes of the dam were obtained in real time with a line temperature measurement pattern instead of a point temperature measurement pattern. Additionally, a framework of distributed optical fiber data acquisition and remote transmission was proposed. Interconnection of multiple DTS hosts and remote transmission of temperature data were realized. Then, two-dimensional temperature fields of a typical dam block in different ages and longitudinal profiles of dam blocks with embedded fibers were reconstructed based on large amounts of temperature monitoring data and the Kriging difference algorithm. Temperature field reconstruction results showed that the temperature distribution law of the concrete arch dam was in accordance with the actual situation.

Numerical studies of the suppression of vortex-induced vibrations of twin box girders by central grids

Li, Zhiguo,Zhou, Qiang,Liao, Haili,Ma, Cunming Techno-Press 2018 Wind and Structures, An International Journal (WAS Vol.26 No.5

A numerical study based on a delayed detached eddy simulation (DDES) is conducted to investigate the aerodynamic mechanism behind the suppression of vortex-induced vibrations (VIVs) of twin box girders by central grids, which have an inhibition effect on VIVs, as evidenced by the results of section model wind tunnel tests. The mean aerodynamic force coefficients with different attack angles are compared with experimental results to validate the numerical method. Next, the flow structures around the deck and the aerodynamic forces on the deck are analyzed to enhance the understanding of the occurrence of VIVs and the suppression of VIVs by the application of central grids. The results show that shear layers are separated from the upper railings and lower overhaul track of the upstream girder and induce large-scale vortices in the gap that cause periodical lift forces of large amplitude acting on the downstream girder, resulting in VIVs of the bridge deck. However, the VIVs are apparently suppressed by the central grids because the vortices in the central gap are reduced into smaller vortices and become weaker, causing slightly fluctuating lift forces on the deck. In addition, the mean lift force on the deck is mainly caused by the upstream girder, whereas the fluctuating lift force is mainly caused by the downstream girder.

Subproteomic profiling from renal cortices in OLETF rats reveals mutations of multiple novel genes in diabetic nephropathy

Li Zhiguo,Shen Hong,Liu Yeqiang,Zhou Xuefeng,Yan Meihua,He Hailan,Zhao Tingting,Zhang Haojun,Li Ping 한국유전학회 2022 Genes & Genomics Vol.44 No.1

Background: Ovarian cancer is a common gynecological malignancy among female patients and poses a serious threat to women's health. Although it has been established that Fos-like antigen 2 (FOSL2) is linked to ovarian cancer (OC), its exact role in the development of OC remains unknown. Objective: This article aims to investigate the role of FOSL2 in ovarian cancer development. Methods: FOSL2 expression in ovarian carcinoma and adjacent tissues was assessed using real-time fluorescent quantitative PCR and western blot. We constructed OE/sh-FOSL2 plasmids and Caspase-1 specific inhibitors (Yvad-CMK) and transfected A 2780 cells with them to identify the relevant cell functions. Furthermore, we used western blot assay to determine the changes in expression of apoptosis-associated speck-like protein containing a CARD (ASC), cysteine aspartate-specific proteasezymogen procaspase 1 (pro-caspase-1), cysteinyl aspartate-specific proteinase-1 (caspase-1), interleukin-1β precursor (pro-IL-1β), interleukin-1β (IL-1β), interleukin-18 precursor (pro-IL-18), and interleukin-18 (IL-18). In addition, we measured the concentration of IL-1β and IL-18 using an enzyme-linked immunosorbent assay (ELISA). Moreover, Tthe level of lactate dehydrogenase (LDH) in the cell supernatant was measured by LDH release assay kit. Results: The expression of FOSL2 was significantly higher compared with the surrounding tissues. The proliferation, migration, and invasion of A2780 cells were enhanced after transfection with OE-FOSL2 plasmids; however, the cell apoptosis was significantly decreased. When FOSL2 was overexpressed, the inflammasome-associated proteins such as ASC, caspase-1, IL-1β, and IL-18 were downregulated. Furthermore, FOSL2 induced apoptosis and activated the production of inflammasomes in A2780 cells. Co-therapy with Yvad-CMK and substantially inhibited apoptosis and activation of inflammasomes. Conclusions: Inhibition of FOSL2 promotes the apoptosis of OC cells by mediating the formation of an inflammasome.

Nanocomposite reinforced structures to deal with injury in physical sports

Guojiao Wang,Kun Peng,Hui Zhou,Guangyao Liu,Zhiguo Lou,Feng Pan Techno-Press 2023 Advances in nano research Vol.14 No.6

The extensive use of polymeric matrix composites in the athletic sector may be attributed to its high strength-to-weight ratio, production economy, and a longer lifespan than conventional materials. This study explored the impact of carbon nanotubes on the properties of different composite field sports equipment components. The test specimens were fabricated using the compression molding technique. The insertion of carbon nanotubes increases mechanical properties related to the process parameters to account for an improvement in the stick sections' overall performance. The dynamic response of functionally graded reinforced nanocomposite wire structure is examined in this paper on the bases of high-order hyperbolic beam theory lined to the size-dependent nonclassical nonlocal theory under the external mechanical load due to the physical activities. Finally, the impact of different parameters on the stability of nanocomposite structures is discussed in detail.

Study on the thermal sensitivity of β-NaYF4: Yb3+-Er3+ nano-thermometers based on luminescence ratiometric technology

Leipeng Li,Feng Qin,Yuan Zhou,Yangdong Zheng,Hua Zhao,Zhiguo Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.4

It is demonstrated here that relative sensitivity should gain more concern than absolute sensitivity when designing a new type of nano-thermometer based on luminescence ratiometric technology. Following the NIR excitation by a 980 nm laser diode, the 520/527 and 540/547 nm upconversion luminescence bands, which are respectively ascribed to the 2H11/2–4I15/2 and 4S3/2–4I15/2 transitions of Er3+ ions embedded in NaYF4 nanocrystals, are investigated as a function of temperature between 303 and 483 K. It is found that the 520/540, 520/ 547, 527/540 and 527/547 nm emission lines can constitute four pairs of thermally coupled energy levels. These four pairs of lines own the different absolute sensitivities. However, the relative sensitivities for them are identical at the same temperature. A third parameter, that is, temperature resolution, is then introduced to identify the difference between the two sensitivities. It is found that these four pairs of lines own the same temperature resolution, suggesting that absolute sensitivity is an intermediate parameter and relative sensitivity reflects the fundamental nature of sensors.

Hot deformation behavior of CNTs/Al-Li composite prepared by powder metallurgy

Jia Lei,Liu Yang,Xing Zhiguo,He Gengchao,Lu Zhenlin,Zhou Yongxin 한국탄소학회 2022 Carbon Letters Vol.32 No.5

CNTs/Al-Li composite was first prepared by hot-pressed sintering from Al-Li alloy powder and CNTs solution, and then the hot compression tests were performed on MMS-100 thermal simulator at strain rate range of 0.01– 10 s−1, deformation temperature range of 350–500 °C, and total deformation amount of 60%. True stress–strain curves were plotted, and constitutive equation as well as hot processing maps were successfully confirmed based on Arrhenius constitutive model and Prasad instability criterion. Results show that CNTs/Al-Li composite have a very poor hot deformation ability and narrow processing region, which is strain rate range of 0.1–1 s−1 and deformation temperature range of 360–400 °C. Hot extrusion experiment was carried out and the processing parameters were selected according to the established hot processing map, and an improvement on strength and a good balance between strength and plasticity can be obtained, which is about 650 MPa for tensile strength and 9% for elongation.

Modeling of the polycrystalline cutting of austenitic stainless steel based on dislocation density theory and study of burr formation mechanism

Jiaxin Wen,Lin He,Tao Zhou,Pengfei Tian,Tian Zhou,Zhiguo Feng 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.6

The presence of burrs in mechanical processing can negatively affect surface integrity and dimensional accuracy and even lead to part scrapping. Grain size also has a significant impact on material properties and subsequently generate different processing effects. However, only few studies have explored the effect of grain size on machined surface integrity and burr formation. To fill this gap, this study develops a model based on dislocation density and incorporates this model into ABAQUS using subroutines to investigate polycrystalline cutting modeling and the burr formation mechanism. In addition, the plastic flow and deformation process of grains are observed using a newly developed 2D polycrystalline model, which is later compared with traditional Johnson-Cook constitutive models. The simulated cutting force value, chip morphology, and experimental results are also compared to preliminarily validate the feasibility of the developed model. The experimental results remain consistent across different simulated cutting speeds and depths. The height and width of the exit burr slightly decrease along with increasing cutting speed. Meanwhile, increasing the cutting depth significantly increases the burr width and height. The lateral burrs observed in the experiment can also be reproduced using a 3D polycrystalline model. The lateral burr size increases along with cutting depth and speed. The effect of grain size on cutting force and burr formation is eventually explored, and results show that increasing the grain size reduces the cutting force but increases the burr size. This study provides a new concept for burr control and surface integrity improvement.

Molecular Identification of Self-Incompatibility Locus in Radish

Yiqin Gong,Tianrong Zhao,Liwang Liu,Mingxia Wang,Zhiguo Zhou 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-