A Study on Shape and Height of Shipwaves

Song-lin Gang,Mi-Kum Kim,Chang-Je Kim 한국항해항만학회 2009 한국항해항만학회지 Vol.33 No.2

Shipwaves can have harmful effects on ships working on the sea. in a harbour or navigational channel and caused beach erosion, seawall destruction. This study aims to investigate describe the characteristics of the wave pattern generated by an individual model ship tested at different velocities and hull forms for a given water depth and to investigate the variations at a given distance from the sailing line under the same conditions. As a result, the angles a's by model ship tests are smaller than those by real ship ones. Wave heights decreases with an increasing the mid-ship cross sectional area As. The maximum wave height and period increase rapidly in the sabcritical speed, and beyond the critical speed the height and period decrease with increasing depth Froude number. And the period keeps constant with the distance from the sailing line.

Influence of different parameters on nonlinear friction-induced vibration characteristics of water lubricated stern bearings

Lin Chang-Gang,Zou Ming-Song,Zhang Hai-Cheng,Qi Li-Bo,Liu Shu-Xiao 대한조선학회 2021 International Journal of Naval Architecture and Oc Vol.13 No.1

To investigate the mechanism of friction-induced vibration and noise of ship water lubricated stern bearings, a two-degree-of-freedom (2-DOF) nonlinear self-excited vibration model is established. The novelty of this work lies in the detailed analysis of influence of different parameters on the stability and nonlinear vibration characteristics of the system, which provides a theoretical basis for the various friction vibration and noise phenomenon and has a very important directive meaning for low noise design of water lubricated stern bearings. The results reveal that the change of any parameter, such as rotating speed of shaft, contact pressure, friction coefficient, system damping and stiffness, has an important influence on the stability and nonlinear response of the system. The vibration amplitudes of the system increase as (a) rotating speed of shaft, contact pressure, and the ratio of static friction coefficient to dynamic friction coefficient increase and (b) the transmission damping between motor and shaft decreases. The frequency spectrum of the system is modulated by the first mode natural frequency, which is continuous multi-harmonics of the first mode natural frequency. The response of the system presents a quasi-periodic motion.

Identification and Functional Analysis of Differentially Expressed Genes Related to Metastatic Osteosarcoma

Niu, Feng,Zhao, Song,Xu, Chang-Yan,Chen, Lin,Ye, Long,Bi, Gui-Bin,Tian, Gang,Gong, Ping,Nie, Tian-Hong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

Background: To explore the molecular mechanisms of metastatic osteosarcoma (OS) by using the microarray expression profiles of metastatic and non-metastatic OS samples. Materials and Methods: The gene expression profile GSE37552 was downloaded from Gene Expression Omnibus database, including 2 human metastatic OS cell line models and 2 two non-metastatic OS cell line models. The differentially expressed genes (DEGs) were identified by Multtest package in R language. In addition, functional enrichment analysis of the DEGs was performed by WebGestalt, and the protein-protein interaction (PPI) networks were constructed by Hitpredict, then the signal pathways of the genes involved in the networks were performed by Kyoto Encyclopaedia of Genes and Genomes (KEGG) automatic annotation server (KAAS). Results: A total of 237 genes were classified as DEGs in metastatic OS. The most significant up- and down-regulated genes were A2M (alpha-2-macroglobulin) and BCAN (brevican). The DEGs were significantly related to the response to hormone stimulus, and the PPI network of A2M contained IL1B (interleukin), LRP1 (low-density lipoprotein receptor-related protein 1) and PDGF (platelet-derived growth factor). Furthermore, the MAPK signaling pathway and focal adhesion were significantly enriched. Conclusions: A2M and its interactive proteins, such as IL1B, LRP1 and PDGF may be candidate target molecules to monitor, diagnose and treat metastatic OS. The response to hormone stimulus, MAPK signaling pathway and focal adhesion may play important roles in metastatic OS.

Effect of metal oxide partial substitution of V2O5 in V2O5–WO3/TiO2 on selective catalytic reduction of NO with NH3

Qing-mao Zhang,Chong-lin Song,Gang Lv,Feng Bin,Hua-ting Pang,Jin-ou Song 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.24 No.-

After partial substitution of V2O5 in V2O5–WO3/TiO2 by metal oxide (MxOy, M = Fe, Co, Ni, Cu, Sr, La, and Ce), the NO conversions for the MxOy–V2O5–WO3/TiO2 catalysts (M-VW) showed the following sequence: Co–VW > Fe–VW > Sr-VW Ce-VW La-VW > VW > Ni-VW > Cu-VW. The reduction activities for almost all the M-VW catalysts were enhanced at reaction temperature >400 8C, but only the Co-VW catalyst showed an increased activity at temperature <400 8C. Among the M-VW catalysts tested, the Co-VW sample had the highest catalytic activity with a temperature range of 300–550 8C for more than 90% NO removal at a GHSV of 60 000 h1. Moreover, the Co-VW sample exhibited high space- velocity, H2O and SO2 resistance, and low N2O yield. Co partial substitution for V in the VW led to more Lewis acid sites and Brønsted acid sites, and an obvious increase in the ratio of the adsorbed oxygen to the lattice oxygen from 12.74% for VW to 36.73% for Co-VW. The increased adsorbed oxygen and Lewis and Brønsted acid sites contributed to the improved SCR activity of the Co-VW sample.

Reactive oxygen species free radical treatment of bamboo flour and its effects on the chemical structure and board bonding strength

( Jin Wang ),( Chun De Jin ),( Jian Gang Song ),( Wei Yang ),( Yuan Lin Cao ) 한국목재공학회 2012 한국목재공학회 학술발표논문집 Vol.2012 No.-

ppGalNAc T1 as a Potential Novel Marker for Human Bladder Cancer

Ding, Ming-Xia,Wang, Hai-Feng,Wang, Jian-Song,Zhan, Hui,Zuo, Yi-Gang,Yang, De-Lin,Liu, Jing-Yu,Wang, Wei,Ke, Chang-Xing,Yan, Ru-Ping Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.11

Objectives: To investigate the effect of glycopeptide-preferring polypeptide GalNAc transferase 1 (ppGalNAc T1 ) targeted RNA interference (RNAi) on the growth and migration of human bladder carcinoma EJ cells in vitro and in vivo. Methods: DNA microarray assays were performed to determine ppGalNAc Ts(ppGalNAc T1-9) expression in human bladder cancer and normal bladder tissues. We transfected the EJ bladder cancer cell line with well-designed ppGalNAc T1 siRNA. Boyden chamber and Wound healing assays were used to investigate changes of shppGalNAc T1-EJ cell migration. Proliferation of shppGalNAc T1-EJ cells in vitro was assessed using [3H]-thymidine incorporation assay and soft agar colony formation assays. Subcutaneous bladder tumors in BALB/c nude mice were induced by inoculation of shppGalNAc T1-EJ cells and after inoculation diameters of tumors were measured every 5 days to determine gross tumor volumes. Results: ppGalNAc T1 mRNA in bladder cancer tissues was 11.2-fold higher than in normal bladder tissues. When ppGalNAc T1 expression in EJ cells was knocked down through transfection by pSUPER-shppGalNAc T1 vector, markedly reduced incorporation of [3H]-thymidine into DNA of EJ cells was observed at all time points compared with the empty vector transfected control cells. However, ppGalNAc T1 knockdown did not significantly inhibited cell migration (only 12.3%). Silenced ppGalNAc T1 expression significantly inhibited subcutaneous tumor growth compared with the control groups injected with empty vector transfected control cells. At the end of observation course (40 days), the inhibitory rate of cancerous growth for ppGalNAc T1 knockdown was 52.5%. Conclusion: ppGalNAc T1 might be a potential novel marker for human bladder cancer. Although ppGalNAc T1 knockdown caused no remarkable change in cell migration, silenced expression significantly inhibited proliferation and tumor growth of the bladder cancer EJ cell line.

A prospective study of the prostate health index density and multiparametric magnetic resonance imaging in diagnosing clinically significant prostate cancer

Yuanchong Chen,Dong Xu,Mingjian Ruan,Haixia Li,Guiting Lin,Gang Song 대한비뇨의학회 2023 Investigative and Clinical Urology Vol.64 No.4

Purpose: To evaluate the predictive performance of the prostate health index (PHI) and PHI density (PHID), for clinically significant prostate cancer (csPCa) in patients with a PI-RADS score ≤3. Materials and Methods: Patients tested for total prostate-specific antigen (tPSA, ≤100 ng/mL), free PSA (fPSA), and p2PSA at Peking University First Hospital were prospectively enrolled. Possible predictive factors of csPCa were analyzed using the receiver operating characteristic (ROC) curve. Results were expressed as area under the curve (AUC) with 95% confidence intervals (CI). The cutoff values of PHI and PHID were determined. Results: We enrolled 222 patients in this study. The prevalence of csPCa in the PI-RADS ≤3 subgroup (n=89) was 22.47% (20/89). Age, tPSA, F/T, prostate volume, PSA density, PHI, PHID, and PI-RADS score were significantly associated with csPCa. PHID (AUC: 0.829 [95% CI: 0.717–0.941]) was the best predictor of csPCa. PHID >0.956 was set as the threshold of suspicious csPCa with a sensitivity of 85.00% and a specificity of 73.91%, avoiding 94.44% of unnecessary biopsies but missing 15.00% csPCa. A threshold of PHI ≥52.83 showed the same sensitivity but a rather lower specificity of 65.22% that avoided 93.75% of unnecessary biopsies. Conclusions: PHI and PHID have the best predictive performance of csPCa in patients with PI-RADS score ≤3. A threshold value of PHID ≥0.956 may be used as the criterion for biopsy in these patients.