Variations of Available Nitrogen along the Upland Meadow in Wugong Mountain

Zhiyang Yuan,Zhi Li,Dekui Niu,Wenyuan Zhang,Xiaomin Guo,Xu Chen,Xiao Cheng 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Combining different forms of statistical energy analysis to predict vibrations in a steel box girder comprising periodic stiffening ribs

Hao Luo,Zhiyang Cao,Xun Zhang,Cong Li,Derui Kong 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.45 No.1

Due to the complexity of the structure and the limits of classical SEA, a combined SEA approach is employed, with angle-dependent SEA in the low- and mid-frequency ranges and advanced SEA (ASEA) considering indirect coupling in the high-frequency range. As an important component of the steel box girder, the dynamic response of an L-junction periodic ribbed plate is calculated first by the combined SEA and validated by the impact hammer test and finite element method (FEM). Results show that the indirect coupling due to the periodicity of stiffened plate is significant at high frequencies and may cause the error to reach 38.4 dB. Hence, the incident bending wave angle cannot be ignored in comparison to classical SEA. The combined SEA is then extended to investigate the vibration properties of the steel box girder. The bending wave transmission study is likewise carried out to gain further physical insight into indirect coupling. By comparison with FEM and classical SEA, this approach yields good accuracy for calculating the dynamic responses of the steel box girder made of periodic ribbed plates in a wide frequency range. Furthermore, the influences of some important parameters are discussed, and suggestions for vibration and noise control are provided.

Food intake and its effect on the species and abundance of intestinal flora in colorectal cancer and healthy individuals

( Weitao Shen ),( Jiayu Sun ),( Zhiyang Li ),( Fen Yao ),( Kaihuang Lin ),( Xiaoyang Jiao ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.3

Background/Aim: It is known that an imbalance in the intestinal f lora plays a crucial role in colorectal cancer (CRC), but the effect of food consumption patterns on the types of intestinal flora remains to be clarified. We aimed to analyze the associations between food intake and intestinal flora in healthy and CRC individuals. Methods: Food intake data were recorded using the Food Frequency Questionnaire (FFQ). The composition and diversity of the intestinal flora detected by 16S rRNA gene sequencing, and the data were analyzed by R version 3.1.1 software. Results: Higher intake of red meat or pickled foods, and lower intake of white meat, fruits, vegetables, beans, nuts were found in the CRC group compared with the healthy group. Higher levels of Fusobacteria and Proteobacteria, and lower levels of Firmicutes were observed in the CRC group. Partial correlation analysis revealed that the intake of fruits, beans, and nuts was negatively correlated with Proteobacteria and Fusobacteria, but pickled food was positively correlated with Fusobacteria (p < 0.05). Fish, beans, and nuts intake was negatively correlated with Escherichia (p = 0.01). Multiple regression analysis revealed that vegetable oil (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.13 to 0.82), vegetables (OR, 0.26; 95% CI, 0.10 to 0.64), eggs (OR, 0.26; 95% CI, 0.10 to 0.69), pickled foods (OR, 21.02; 95% CI, 6.02 to 73.45), and red meat (OR, 4.23; 95% CI, 1.68 to 10.60) had an impact on CRC risk. Conclusions: The species and abundance of intestinal flora varies between CRC and healthy individuals and may be affected by their food preference.

Dynamic Response of High Strength Steel Beams Subjected to Explosion Induced Blast Load

Xinchang Feng,Xiyue Liu,Zhiyang He,Shuxin Bai,Shun Li,Yu Tang 한국강구조학회 2023 International Journal of Steel Structures Vol.23 No.6

A series of anti-explosion tests were performed on H-type high strength steels (Q460JSC and HQ600) and ordinary steels (Q345B) to address the problem of anti-explosion in the technical application of high strength steel. The dynamic behavior of steel beams during explosion and the propagation of shock waves were analyzed. The effects of proportionate distance, steel strength, high-span ratio, section shapes were investigated. The finite element software (ANSYS/LS-DYNA) was used to analyze the anti-explosion performance of high strength steel beams. The finite element models which adopted modified Johnson–Cook constitutive model and damage criterion were validated by comparing with the experimental results. The influence factors of anti-explosion performance of high strength steel were explored by numerical simulation as well. The results reveal that under near-explosion conditions, the peak values of overpressure predicted by empirical formulas are often less than the experimental outcomes. As the scaled distance reduces, the damage to the steel beam increases, making it more prone to local fracture. By decreasing the scaled distance, increasing the high-span ratio, and strengthening the constraint of H-type steel beam, the deformation and damage of steel beams can reduce. The results provide an effective basis to evaluate the safety of high strength steel beams applied in practical engineering when subjected to explosion.

High-Speed Milling of Hardened Mold Steel P20 with Minimum Quantity Lubrication

Shixiong Wu,Hongchang Liao,Suyang Li,Jundong Bi,Zhiyang Li 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.5

Strong thermal–mechanical coupling and rapid tool failure easily occur in the milling process of hardened steel with solid end mills. This work investigates the effectiveness of minimum quantity lubrication (MQL) during high-speed milling of hardened mold steel. Three kinds of spraying modes were designed in the experiment. They are namely the spraying ways to the flank face (MQL-F), to the rake face (MQL-R) and to the rake and flank faces (MQL-FR). The cutting forces, tool wear, and chips when using the MQL modes and compressed air cooling mode (CAIR-F) were compared, and the wear mechanism and lubrication mechanism were further analyzed. The results showed that the tool wear values and milling forces of several MQL modes were significantly lower than those with CAIR-F. The milling force and tool wear values were successively reduced using MQL-R, MQL-F, and MQL-FR, with better lubrication of the rake face resulting in a smaller curvature radius for the chip. Abrasion wear, adhesion/attrition wear, and flaking/chipping were the main wear mechanisms. The MQL-FR method was the optimal method of the MQL modes. It could effectively reduce the cutting contact stress and unit cutting energy, and obviously reduced wear phenomena such as adhesion and chipping.

Differential Privacy via Weighted Sampling Set Cover

Zhonglian Hu,Zhaobin Liu,Yangyang Xu,Zhiyang Li 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.4

Differential privacy is a security guarantee model which widely used in privacy preserving data publishing, but the query result can’t be used in data research directly, especially in high-dimensional datasets. To address this problem, we propose a dimensionality reduction method. The core idea of this method is using a series of low-dimensional datasets to reconstruct a high-dimensional dataset, it improves data availability eventually. The main issue of this method is the reconstruction integrity, so a special sampling via set cover model is proposed in this article, which builds a multidimensional composite marginal tables set as a new middleware in differential privacy model. As a result, any form of disjunctive queries can be answered, and the accuracy of data query is improved. The experiment results also show the effectiveness of our method in practice.

Role of Subordinate Phases on the Dry Impact‑Abrasion Behavior of Low Chromium Cast Iron

Yu Pei,Renbo Song,Yi Li,Zhiyang Zhao,Yingchao Zhang 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.12

In order to study the resistance mechanism of materials having high resistance to impact-abrasion, synergistic effect ofsubordinate phases of 2.20 wt%C–3.45 wt%Cr–3.06 wt%Mn–1.32 wt%Si–0.51 wt%Cu–0.31 wt%Ni–0.002 wt%B cast ironwas investigated under dry impact-abrasion. Subordinate phases consist of graphite, secondary precipitates and retainedaustenite. Results show that the synergistic effect of above subordinate phases can prevent matrix and carbide from peelingoff, and minimize the damage of carbide to matrix. This effect reduces the depth and width of groove from 7 to 1.2 μm andfrom 14 to 2.5 μm respectively. Above significant improvement is owing that: (1) Graphite can disperse external/internalstress, and fill carbide peeling pits. (2) Secondary precipitates, such as [Fe, Ni] and [Cr, Ni], can disperse the concentratedstress of carbide, inhibiting peeling. (3) Retained austenite can disperse the internal concentrated stress which is transferredfrom the carbide and fine precipitates to matrix.

Checking Relationship Consistency and Class Redundancy in a Class Diagram under Model-Driven Engineering

Liang Huang,Yucong Duan,Honghao Gao,Hui Li,Caimao Li,Zhiyang Lin 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.10

Model-Driven Engineering (MDE) tries to reduce the effort spent on software development by generating codes from models. People concentrate their minds on the transformation between models and models, or between models and codes. People also concentrate on checking consistency between different models such as consistency between a class diagram and a sequence diagram and consistency between a sequence diagram and a state machine diagram. Checking relationship consistency and class redundancy in a class model is still important but ignored in recent years. This paper concentrates on relationship problems between classes in a class diagram and proposes methods of checking various relationship problems. We address the redundancy of a class’s operations and attributes. We identify a large range of the problems for class diagram. Our research is based on the relationship abstraction rules.

Candidate Pruning-Based Differentially Private Frequent Itemsets Mining

Yangyang Xu,Zhaobin Liu,Zhonglian Hu,Zhiyang Li 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.7

Frequent Itemsets Mining(FIM) is a typical data mining task and has gained much attention. Due to the consideration of individual privacy, various studies have been focusing on privacy-preserving FIM problems. Differential privacy has emerged as a promising scheme for protecting individual privacy in data mining against adversaries with arbitrary background knowledge. In this paper, we present an approach to exploring frequent itemsets under rigorous differential privacy model, a recently introduced definition which provides rigorous privacy guarantees in the presence of arbitrary external information. The main idea of differentially privacy FIM is perturbing the support of item which can hide changes caused by absence of any single item. The key observation is that pruning the number of unpromising candidate items can effectively reduce noise added in differential privacy mechanism, which can bring about a better tradeoff between utility and privacy of the result. In order to effectively remove the unpromising items from each candidate set, we use a progressive sampling method to get a super set of frequent items, which is usually much smaller than the original item database. Then the sampled set will be used to shrink candidate set. Extensive experiments on real data sets illustrate that our algorithm can greatly reduce the noise scale injected and output frequent itemsets with high accuracy while satisfying differential privacy.

Molecular Cloning, Identification and Characteristics of a Novel Isoform of Carbamyl Phosphate Synthetase I in Human Testis

Huo, Ran,Zhu, Hui,Lu, Li,Ying, Lanlan,Xu, Min,Xu, Zhiyang,Li, Jianmin,Zhou, Zuomin,Sha, Jiahao Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.1

A gene coding a novel isoform of carbamyl phosphate synthetase I (CPS1) was cloned from a human testicular library. As shown by cDNA microarray hybridization, this gene was expressed at a higher level in human adult testes than in fetal testes. The full length of its cDNA was 3831 bp, with a 3149 bp open reading frame, encoding a 1050-amino-acid protein. The cDNA sequence was deposited in the GenBank (AY317138). Sequence analysis showed that it was homologous to the human CPS1 gene. The putative protein contained functional domains composing the intact large subunit of carbamoyl phosphate synthetase, thus indicated it has the capability of arginine biosynthesis. A multiple tissue expression profile showed high expression of this gene in human testis, suggesting the novel alternative splicing form of CPS1 may be correlated with human spermatogenesis.