• International conference on construction engineering and project management
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• 2005.10a
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• pp.796-801
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• 2005

Time management is one of the critical tasks in project management. Based on the theories of total quality management, this authors presented a project time management method, total time management (TTM), so as to facilitate highway project time management. This paper discussed the four fundamental characteristics of TTM: total factors management, staff management, project life cycle management, and Plan-Do-Check-Action (PDCA) cycle management. Now, most managers use computer software to manage the project. In order to make the theory of TTM more executable, the authors develop a project time management system suitable for TTM. This paper presents this time management system's analysis processes including system requirement, key functions etc..

• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1213-1227
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• 2023

Fetal growth restriction (FGR) is a prevalent obstetric condition. This study aimed to investigate the role of Toll-like receptor 9 (TLR9) in regulating the inflammatory response and gut microbiota structure in FGR. An FGR animal model was established in rats, and ODN1668 and hydroxychloroquine (HCQ) were administered. Changes in gut microbiota structure were assessed using 16S rRNA sequencing, and fecal microbiota transplantation (FMT) was conducted. HTR-8/Svneo cells were treated with ODN1668 and HCQ to evaluate cell growth. Histopathological analysis was performed, and relative factor levels were measured. The results showed that FGR rats exhibited elevated levels of TLR9 and myeloid differentiating primary response gene 88 (MyD88). In vitro experiments demonstrated that TLR9 inhibited trophoblast cell proliferation and invasion. TLR9 upregulated lipopolysaccharide (LPS), LPS-binding protein (LBP), interleukin (IL)-1β and tumor necrosis factor (TNF)-α while downregulating IL-10. TLR9 activated the TARF3-TBK1-IRF3 signaling pathway. In vivo experiments showed HCQ reduced inflammation in FGR rats, and the relative cytokine expression followed a similar trend to that observed in vitro. TLR9 stimulated neutrophil activation. HCQ in FGR rats resulted in changes in the abundance of Eubacterium_coprostanoligenes_group at the family level and the abundance of Eubacterium_coprostanoligenes_group and Bacteroides at the genus level. TLR9 and associated inflammatory factors were correlated with Bacteroides, Prevotella, Streptococcus, and Prevotellaceae_Ga6A1_group. FMT from FGR rats interfered with the therapeutic effects of HCQ. In conclusion, our findings suggest that TLR9 regulates the inflammatory response and gut microbiota structure in FGR, providing new insights into the pathogenesis of FGR and suggesting potential therapeutic interventions.

• Kyungpook Mathematical Journal
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• v.45 no.1
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• pp.123-130
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• 2005

In this paper we discuss a class of analytic functions related to the starlike functions in the unit disk. We prove that this class belongs to the class of close-to-convex functions, we obtain the sharp coefficient upper bounds and distortion theorem of this class, we also get the convexity radius of this class.

• Communications of the Korean Mathematical Society
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• v.23 no.1
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• pp.49-59
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• 2008

In this paper, we prove the sharp estimates for multilinear commutator related to Littlewood-Paley operator. By using the sharp estimates, we obtained the weighted $L^p$-norm inequality for the multilinear commutator for 1 < p < $\infty$.

• Wind and Structures
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• v.17 no.2
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• pp.163-184
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• 2013

An accurate identification of the aerodynamic characteristics of vehicles and the bridge is the premise for the coupled vibration analysis of a wind-vehicle-bridge system. At present, the interaction of aerodynamic forces between the road vehicles and bridge is ignored in most previous studies. In the present study, an experimental setup was developed to measure the aerodynamic characteristics of vehicles and the bridge for different cases in a wind tunnel considering the aerodynamic interference. The influence of the wind turbulence, the wind speed, the vehicle interference, and the vehicle position on the aerodynamic coefficients of vehicles, and the influence of vehicles on the static coefficients of the bridge were investigated, based on the experimental results. The variations in the aerodynamic characteristics of vehicles and the bridge were studied and the measured results were validated according to the results of surface pressure measurements on the vehicle and the bridge. The measured results were further validated by comparing the measured results with values derived numerically. The measured results showed that the wind turbulence, the vehicle interference, and the vehicle position significantly affected the aerodynamic coefficients of vehicles. However, the influence of the wind speed on the aerodynamic coefficients of the studied vehicle is small. The static coefficients of the bridge were also significantly influenced by the presence of vehicles.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.63-67
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• 1992

This paper reports the effects of rare earth nitrate (REN) on the growth of internal organs and mineral elements in serums of broiler chickens. The REN used is mixture of light RE containing mainly La, Ce, Pr and Nd 4 elements. 40 eight-week old AA broiler chickens were divided randomly into four groups that their treatments were respectively 0, 20, 200 and 2000 mg REN/kg feed and the duration of the experiment was 60 days. Responses were measured in terms of internal organic weight and tissue, contents of mineral elements in serums. There were no significant differences between the organ ratios and tissue changes of the 20, 200 mg REN/kg groups and the control group. The organs included the heart, liver, kidneys, lungs, testicles, thyroids, adrenal glands, pancreas, tonsies of caecum, stomachus glandularis, duodenum, ileum and bursa of Fabricius. The liver and thyroid indices of 2000 mg REN/kg group were significantly higher than those of the control group (p < 0.01, p < 0.05) and the adrenal gland index lower (p < 0.05). The pathlolgic changes in the heart, kidney and thyroid were more serious than that of the control group. No significant differences occurred between the contents of K, Na, Mg elements in the serum of all groups, with the exception of the content of Ca, which was higher in the 2000 mg/kg group (p < 0.05). The contents of all trace elements including Mn, Zn and Cu, but except Fe, in the serums of all the treated groups were significantly higher than those of the control group (p < 0.01).

• Journal of the Korean Chemical Society
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• v.59 no.2
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• pp.142-147
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• 2015

Two new chitosan derivatives, polyamine grafted chitosan copolymers have been synthesized for corrosion protection of carbon steel in acidic medium. First, methyl acrylate graft chitosan copolymer (CS-MAA) was prepared by the reaction of chitosan (CS) and methyl acrylate (MAA) via the Michael addition reaction. Then, CS-MAA was reacted with ethylene diamine (EN) and triethylene tetramine (TN) respectively to synthesize ethylene diamine grafted chitosan copolymer (CS-MAA-EN) and triethylene tetramine grafted chitosan copolymer (CS-MAA-TN), and the structures were characterized by Fourier-transform infrared spectroscopy (FT-IR). At last, the corrosion inhibition activities on Q235 carbon steel were investigated by using gravimetric measurements, metallographic microscope, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The compounds CS-MAA-EN and CS-MAA-TN show an appreciable corrosion inhibition property against corrosion of Q235 carbon steel in 5% HCl solution at $25^{\circ}C$. It has been observed that CS-MAA-EN shows greater corrosion inhibition efficiency than CS-MAA-TN. The inhibition efficiency of CS-MAA-EN was close to 90% when the mass fraction concentration was 0.2%~0.3%; the inhibition efficiency of CS-MAA-TN was close to 85% when the mass fraction concentration was 0.02%. The present work provided very promising results in the preparation of green corrosion inhibitors.

• Journal of Information Processing Systems
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• v.14 no.6
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• pp.1464-1479
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• 2018

In face recognition, sometimes the number of available training samples for single category is insufficient. Therefore, the performances of models trained by convolutional neural network are not ideal. The small sample face recognition algorithm based on novel Siamese network is proposed in this paper, which doesn't need rich samples for training. The algorithm designs and realizes a new Siamese network model, SiameseFacel, which uses pairs of face images as inputs and maps them to target space so that the $L_2$ norm distance in target space can represent the semantic distance in input space. The mapping is represented by the neural network in supervised learning. Moreover, a more lightweight Siamese network model, SiameseFace2, is designed to reduce the network parameters without losing accuracy. We also present a new method to generate training data and expand the number of training samples for single category in AR and labeled faces in the wild (LFW) datasets, which improves the recognition accuracy of the models. Four loss functions are adopted to carry out experiments on AR and LFW datasets. The results show that the contrastive loss function combined with new Siamese network model in this paper can effectively improve the accuracy of face recognition.

• Geomechanics and Engineering
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• v.31 no.4
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• pp.395-407
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• 2022

In this paper, cracks with different angles are prefabricated in rock specimens to study the fracture characteristics of rock based on CT images. The rock specimens are prepared for compression tests according to the standard recommended by ISRM (International Society for Rock Mechanics). The effects of different angles on rock mechanical properties and crack propagation fracture modes are analyzed. Then, based on the cohesive element method and CT images, the relationship between porosity and Young's modulus as well as the fracture property is explored by the numerical modelling. In the modelling, the distribution of Young's modulus is determined by the CT image through the field variable method. The results show that prefabricated cracks reduce the mechanical properties of rock. The closer the angles of the prefabricated crack is, the greater the Young's modulus of the rock sample is. The failure process of each specimen with prefabricated cracks is formed by the initiation and propagation of crack, and the angle of the prefabricated crack will affect the type of extended crack. As part of the numerical model proposed in this paper, the microstructure of rocks is reflected by CT images. The numerical results verify the effectiveness of the cohesive element method in the study of crack propagation for rock. The rock model in this paper can be used to predict engineering disasters such as collapse and landslide caused by rock fracture, which means that the methodology adopted in this paper is comprehensive and important to solve rock engineering problems.

• Geomechanics and Engineering
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• v.38 no.4
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• pp.381-395
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• 2024

With the wide application of urban subway tunnels, the foundation pits of new stations and existing subway tunnels are becoming increasingly close, and even zero-distance close-fitting construction has taken place. To optimize the construction support scheme, the existing tunnel's vertical displacement is theoretically analyzed using the two-stage analysis method to understand the action mechanism of the construction of zero-distance deep large foundation pits on both sides of the existing stations; a three-dimensional numerical calculation is also performed for further analysis. First, the additional stress field on the existing tunnel caused by the unloading of zero-distance foundation pits on both sides of the tunnel is derived based on the Mindlin stress solution of a semi-infinite elastic body under internal load. Then, considering the existing subway tunnel's joints, shear stiffness, and shear soil deformation effect, the tunnel is regarded as a Timoshenko beam placed on the Kerr foundation; a sixth-order differential control equation of the tunnel under the action of additional stress is subsequently established for solving the vertical displacement of the tunnel. These theoretical calculation results are then compared with the numerical simulation results and monitoring data. Finally, an optimized foundation pit support scheme is obtained considering the pit corner effect and external corner failure mode. The research shows a high consistency between the monitoring data,analytical and numerical solution, and the closer the tunnel is to the foundation pit, the more uplift deformation will occur. The internal corner of the foundation pit can restrain the deformation of the tunnel and the retaining structure, while the external corner can cause local stress concentration on the diaphragm wall. The proposed optimization scheme can effectively reduce construction costs while meeting the safety requirements of foundation pit support structures.