Numerical studies on flow-induced motions of a semi-submersible with three circular columns

Tian Chenling,Liu Mingyue,Xiao Longfei,Lu Haining,Wang Jin 대한조선학회 2021 International Journal of Naval Architecture and Oc Vol.13 No.1

The semi-submersible with three circular columns is an original concept of efficient multifunctional platform, which can be used for marginal oil, gas field, and Floater of Wind Turbines (FOWT). However, under certain flow conditions, especially in uniform current with specific velocities, the eddies will alternatively form and drop behind columns, resulting in the fluctuating lift force and drag force. Consequently, the semi-submersible will subject to the Flow-Induced Motions (FIM). Based on the Detached Eddy Simulation (DES) method, the numerical studies were carried out to understand the FIM characteristics of the three-column semi-submersible at two different parameters, i.e., current incidences (0, 30, and 60-incidences) and reduced velocities (4 Ur 14). The results indicate that the lock-in range of 6 Ur 10 for the transverse motions is presented, and the largest transverse nondimensional nominal amplitude is observed at 60-incidence, with a value of Ay=D ¼ 0:481. The largest yaw amplitude Ayaw is around 3.0 at 0-incidence in the range of 8 Ur 12. The motion magnitude is basically the same as that of a four-column semi-submersible. However, smaller responses are presented compared to those of the three-column systems revealing the mitigation effect of the pontoon on FIM.

The mitochondrial genome of the Kentish Plover Charadrius alexandrinus (Charadriiformes: Charadriidae) and phylogenetic analysis of Charadrii

Wan Chen,Chenling Zhang,Tao Pan,Wei Liu,Kexin Li,Chaochao Hu,Qing Chang 한국유전학회 2018 Genes & Genomics Vol.40 No.9

The suborder Charadrii (Aves: Charadriiformes), one of the most species-rich radiations within shorebirds, which contains good source for studies of ecology, behaviour and evolution. The resources of mitogenome have rapidly accumulated in recent years due to the advanced genomic sequencing, while suborder Charadrii’s mitogenome has not been well studied. The primary objective of this study was to determine the complete mitogenome sequence of Charadrius alexandrinus, and investigated the evolutionary relationship within Charadrii. The mitogenome of C. alexandrinus were generated by amplification of overlapping Polymerase Chain Reaction (PCR) fragments. In this study, we determined the complete mitogenome sequence of the Kentish Plover Charadrius alexandrinus, and comparative analysed 11 species to illustrate mitogenomes structure and investigated their evolutionary relationship within Charadrii. The Charadrii mitogenomes displayed moderate size variation, the mean size was 16,944 bp (SD = 182, n = 11), and most of the size variation due to mutations in the control region (CR). Nucleotide composition was consistently biased towards AT rich, and the A+T content also varies for each protein-coding genes. The variation in ATP8 and COIII was the highest and lowest respectively. The GC skew was always negative, with the ATP8 had higher value than other regions. The average uncorrected pairwise distances revealed heterogeneity of evolutionary rate for each gene, the COIII, COI and COII have slow evolutionary rate, whereas the gene of ATP8 has the relative fast rate. The highest value of Ks and Ka were ND1 and ATP8, and the ratios of Ka/Ks are lower than 0.27, indicating that they were under purifying selection. Phylogenomic analysis based on the complete mitochondrial genomes strongly supported the monophyly of the suborder Charadrii. This study improves our understanding of mitogenome structure and evolution, and providing further insights into phylogeny and taxonomy in Charadrii. In future, sequencing more mitogenomes from various taxonomic levels will significantly improve our understanding of phylogenetic relationships within Charadrii.

fects of Dietary Soy Intake on Maternal Thyroid Functions and Serum Anti-Thyroperoxidase Antibody Level During Early Pregnancy

Jing Li,Xiaochun Teng,Weiwei Wang,Yanyan Chen,Xiaohui Yu,Shen Wang,Jianxin Li,Lin Zhu,Chenyan Li,Chenling Fan,Hong Wang,Hongmei Zhang,Weiping Teng,Zhongyan Shan 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.5

Soy and its isoflavones have been suggested to suppress thyroperoxidase (TPO), induce goiter, inhibit deiodinase, and modulate immune functions. This study initially investigated the effects of dietary soy consumption on maternal thyroid functions and anti-TPO antibody (TPOAb) production during early pregnancy. Data were collected through questionnaire from 505 women enrolled during early pregnancy by random sampling in Shenyang, China. Based on soy intake frequency, the subjects were divided into three groups (frequent [three or more times per week], conventional [more than twice per month but less than three times per week], and occasional [two or fewer times per month]). Serum thyrotropin (TSH), free thyroxine (FT_4), and TPOAb were measured by chemiluminescence immunoassay. Additionally, the concentrations of two primary isoflavones (daidzein and genistein) and creatinine were assessed in the spot urine samples from representative subjects (about 20%) randomly selected from the three groups. The percentages of frequent, conventional, and occasional consumers were 18.6%, 62.6%, and 18.8%, respectively. No difference was found in age, medical records, family history of thyroid diseases, serum FT_4, TSH, and TPOAb levels, TPOAb-positive percentages, or prevalence of thyroid dysfunctions among the groups. Both urinary daidzein and genistein levels were significantly higher in the frequent consumers compared with the other two groups. No correlations were found between urinary isoflavone levels and serum FT_4 or TSH. Urinary isoflavone levels were not significantly different between TPOAb-positive and -negative women among the randomly selected representative subjects. On the whole, our findings suggest dietary soy consumption during early pregnancy is not associated with the development of thyroid dysfunction or autoimmunity.

Semi-fragile Watermarking Scheme for H.264/AVC Video Content Authentication Based on Manifold Feature

( Chen Ling ),( Obaid Ur-rehman ),( Wenjun Zhang ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.12

Authentication of videos and images based on the content is becoming an important problem in information security. Unfortunately, previous studies lack the consideration of Kerckhoffs`s principle in order to achieve this (i.e., a cryptosystem should be secure even if everything about the system, except the key, is public knowledge). In this paper, a solution to the problem of finding a relationship between a frame`s index and its content is proposed based on the creative utilization of a robust manifold feature. The proposed solution is based on a novel semi-fragile watermarking scheme for H.264/AVC video content authentication. At first, the input I-frame is partitioned for feature extraction and watermark embedding. This is followed by the temporal feature extraction using the Isometric Mapping algorithm. The frame index is included in the feature to produce the temporal watermark. In order to improve security, the spatial watermark will be encrypted together with the temporal watermark. Finally, the resultant watermark is embedded into the Discrete Cosine Transform coefficients in the diagonal positions. At the receiver side, after watermark extraction and decryption, temporal tampering is detected through a mismatch between the frame index extracted from the temporal watermark and the observed frame index. Next, the feature is regenerate through temporal feature regeneration, and compared with the extracted feature. It is judged through the comparison whether the extracted temporal watermark is similar to that of the original watermarked video. Additionally, for spatial authentication, the tampered areas are located via the comparison between extracted and regenerated spatial features. Experimental results show that the proposed method is sensitive to intentional malicious attacks and modifications, whereas it is robust to legitimate manipulations, such as certain level of lossy compression, channel noise, Gaussian filtering and brightness adjustment. Through a comparison between the extracted frame index and the current frame index, the temporal tempering is identified. With the proposed scheme, a solution to the Kerckhoffs`s principle problem is specified.

PDE4 inhibitor suppresses PGE2-induced osteoclast formation via COX-2-mediated p27(KIP1) expression in RAW264.7 cells.

Chen, Ling,Zheng, Ting,Park, Hyojung,Noh, A Long Sae Mi,Lee, Jung-Min,Lee, Dong-Seok,Yim, Mijung Govi-Verlag Pharmazeutischer Verlag [etc.] ; Verla 2011 PHARMAZIE Vol.66 No.3

<P>We investigated the effects of phosphodiesterase 3 (PDE3) and PDE4 inhibitors, which are cAMP degrading enzymes, on prostaglandin E2 (PGE2)-induced osteoclast formation. A PDE4 inhibitor decreased PGE2-induced osteoclast formation, whereas a PDE3 inhibitor did not, possibly due to the lack of PDE3 expression in RAW 264.7 cells. Cell cycle analysis revealed that the PDE4 inhibitor stimulated PGE2-induced p27(KIP1) expression, which leads to increased growth arrest at G0/G1 phase. The PDE4 inhibitor increased cyclooxygenase 2 (COX-2) expression in the presence of PGE2. COX-2 overexpression was associated with growth suppression via p27(KIP1) expression in RAW 264.7 cells. Taken together, our data demonstrate that the PDE4 inhibitor enhances PGE2-induced growth arrest of osteoclast precursors via COX-2-mediated p27(KIP1) expression, which in turn negatively regulates osteoclast formation.</P>

PARALLEL ALGORITHMS ON HYPERCUBE FOR SINGULAR VALUE DECOMPOSITION

Chen Ling,Yin Xin Chun 대한전자공학회 1992 대한전자공학회 Conference Vol.1992 No.2

Tourism Destination Selection Attributes, Tourist Satisfaction and Behavioral Intentions of Multicultural Families in South Korea: Focusing on Self-Efficacy

Chen Ling,Woo-Jin Shin,Alan Dixon Brown People & Global Business Association 2024 Global Business and Finance Review Vol.29 No.3