가역 투자율 측정에 의한 1Cr-1Mo-0.25V 강의 열화도 평가

유권상,김용일,남승훈,유광민,조육,손대락 한국비파괴검사학회 2000 한국비파괴검사학회지 Vol.20 No.5

고온에서 운용 중인 설비의 안전성을 평가하기 위해서는 사용기간동안 열화된 재료의 물성을 측정하여야 한다. 실제 사용되고 있는 화력발전소 터빈의 로터에서 열화도가 다른 여러 종류의 시편을 입수하기 어렵기 때문에, 터빈 로터재로 널리 사용되고 있는 1Cr-1Mo-0.25V 강을 인공열화시켜 시편으로 사용하였다. 열화도의 비파괴적 평가를 위하여 교류 섭동 자기장을 인가하여 가역 투자율을 측정하는 자기적 방법을 사용하였다. 열화도의 증가에 따라 경도와 가역 투자율 피크 사이의 간격은 감소하였는데, 경도와 가역 투자율 피크 간격과의 선형관계를 이용하여 비파괴적으로 터빈 로터강의 열화도를 평가할 수 있는 기초를 마련하였다. The integrity of the turbine totors can be assessed by measuring reversible permeability and Vickers hardness of the aged rotors at service temperature. The measurement system of reversible permeability, which measured by applied alternating perturbing magnetic field, was constructed in order to evaluate matrial degradation, nondestructively. The test specimen was 1Cr-1Mo-0.25V steel used widely for turbine rotor material, and the specimens were prepared by the isothermal heat treatment at 630 ℃. The reversible permeability of the test materials were measured at room temperature. The peak interval of reversible permeability and Vickers hardness decreased with the increase of degradation. The degradation of test material may be determined nondestructively by the lineality of Vickers hardness and the peak interval of reversible permeability.

Using Multidetector-Row CT for the Diagnosis of Afferent Loop Syndrome Following Gastroenterostomy Reconstruction

Yu-Hsiu Juan,Wei-Chou Chang,Chih-Yung Yu,Hsian-He Hsu,Guo-Shu Huang,De-Chuan Chan,Chang-Hsien Liu,Ho-Jui Tung 연세대학교의과대학 2011 Yonsei medical journal Vol.52 No.4

Purpose: To assess the clinical manifestations and multidetector-row computed tomography (MDCT) findings of afferent loop syndrome (ALS) and to determine the role of MDCT on treatment decisions. Materials and Methods: From January 2004 to December 2008, 1,100 patients had undergone gastroenterostomy reconstruction in our institution. Of these, 22 (2%) patients were diagnosed as ALS after surgery that included Roux-en-Y gastroenterotomy (n=9), Billroth-II gastrojejunostomy (n=7), and Whipple’s operation (n=6). Clinical manifestations and MDCT features of these patients were recorded and statistically analyzed. The presumed etiologies of obstruction shown on the MDCT were correlated with clinical information and confirmed by surgery or endoscopic biopsy. Results: The most common clinical symptom was acute abdominal pain, presenting in 18 patients (82%). We found that a fluid-filled C-shaped afferent loop in combination with valvulae conniventes projecting into the lumen was the most common MDCT features of ALS. Malignant causes of ALS, such as local recurrence and carcinomatosis, are the most common etiologies of obstruction. These etiologies and associated complications can be predicted 100% by MDCT. Conclusion: Our results suggest that MDCT is a reliable modality for assessing the etiologies of ALS and guiding treatment decisions.

Pathological Impact on the Phyllosphere Microbiota of Artemisia argyi by Haze

( Yu-zhu Zhang ),( De-yu Jiang ),( Chi Zhang ),( Kun Yang ),( Huai-fu Wang ),( Xiu-wen Xia ),( Wei-jun Ding ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.4

The pathological impact of haze upon the phyllosphere microbiota awaits investigation. A moderate degree of haze environment and a clean control were selected in Chengdu, China. Artemisia argyi, a ubiquitously distributed and extensively applied Chinese herb, was also chosen for experiment. Total genome DNA was extracted from leaf samples, and for metagenome sequencing, an Illumina HiSeq 2500 platform was applied. The results showed that the gene numbers of phyllosphere microbiota derived from haze leaves were lower than those of the clean control. The phyllosphere microbiota derived from both haze and clean groups shared the same top ten phyla; the abundances of Proteobacteria, Actinomycetes and Anorthococcuso of the haze group were substantially increased, while Ascomycetes and Basidiomycetes decreased. At the genus level, the abundances of Nocardia, Paracoccus, Marmoricola and Knoelia from haze leaves were markedly increased, while the yeasts were statistically decreased. KEGG retrieval demonstrated that the functional genes were most annotated to metabolism. An interesting find of this work is that the phyllosphere microbiota responsible for the synthesis of primary and secondary metabolites in A. argyi were significantly increased under a haze environment. Relatively enriched genes annotated by eggNOG belong to replication, recombination and repair, and genes classified into the glycoside hydrolase and glycosyltransferase enzymes were significantly increased. In summary, we found that both structure and function of phyllosphere microbiota are globally impacted by haze, while primary and secondary metabolites responsible for haze tolerance were considerably increased. These results suggest an adaptive strategy of plants for tolerating and confronting haze damage.

Dielectric properties and microstructures of (CaxSr1-x) ZrO3 ceramics

Yu-De Li,Jian-Ming Chen,Ying-Chieh Lee 한양대학교 세라믹연구소 2018 Journal of Ceramic Processing Research Vol.19 No.6

The effects of Ca/Sr ratio and the sintering temperature on the properties of (CaxSr(1-x))ZrO3 (CSZ) ceramics were investigatedin this study. CSZ ceramics were prepared using solid-state reaction process, which were sintered in air at temperaturesranging from 1350 oC to 1450 oC. Their structures were characterized by X-ray Diffraction (XRD), Scanning ElectronMicroscopy (SEM), and Transmission Electron Microscopy (TEM). The change in Ca/Sr ratio significantly affected thecrystalline phase and the dielectric properties of the (CaxSr(1-x))ZrO3 ceramics. The secondary phase, Ca0.15Zr0.85O1.85, wasobserved and increased correspondingly with the rising of sintering temperatures. In order to understand the effects ofsecondary phase on the dielectric properties of CSZ ceramics, the Ca0.15Zr0.85O1.85 phase was prepared individually using solidstatemethod. The Ca0.15Zr0.85O1.85 ceramics sintered at 1500 oC for 2 hours possessed a dielectric constant (εr) of 21.7, adielectric loss (tanδ) of 49.510−4 and an Insulation Resistance (IR) of 2.1 × 1010 Ω. The (Ca0.7Sr0.3)ZrO3 ceramics exhibited thebest dielectric properties, with a permittivity of 29, a dielectric loss (tanδ) of 2.7 × 10−4, and an Insulation Resistance (IR) of2.6 × 1012 Ω.

Soluble Vascular Endothelial Growth Factor Decoy Receptor FP3 Exerts Potent Antiangiogenic Effects

Yu, De-Chao,Lee, Jung-Sun,Yoo, Ji Young,Shin, Hyewon,Deng, Hongxin,Wei, Yuquan,Yun, Chae-Ok Elsevier 2012 Molecular therapy Vol.20 No.5

Prognostic Role of C-reactive Protein in Gastric Cancer: A Meta-analysis

Yu, Qing,Yu, Xiong-Fei,Zhang, Shou-De,Wang, Hao-Hao,Wang, Hai-Yong,Teng, Li-Song Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Background: A number of studies have investigated the association between increased pretreatment serum C-reactive protein (CRP) levels and the prognosis of gastric cancer. However, due to the inconsistent results, whether the serum CRP level can be a prognostic factor in primary gastric cancer remains controversial. Methods: We searched Medline, PubMed, Embase and the Cochrane Central Register of Controlled Trials for relevant high-quality reports. A meta-analysis was carried out using the included studies to assess the association between pretreatment serum CRP level and overall survival (OS) in patients with gastric cancer. Correlation analyses were conducted to evaluate the relationship between serum CRP and tumor characteristics such as tumor node metastasis (TNM) stage and recurrence. Results: Twelve reports involving 2,597 patients with gastric cancer were included. Primary meta-analysis indicated a significant association between elevated CRP level and poor OS (HR 1.77, 95% CI 1.56-2.00). Subgroup analyses showed no single factor could alter the primary results when we divided the included studies by "number of patients", "max follow-up period", "TNM stage", "treatment" and "cut-off value". Correlation analyses showed that serum CRP level was significantly related to TNM stage (OR 2.96, 95% CI 2.22-3.93) and tumor recurrence (OR 1.81, 95% CI 1.21-2.71). Conclusions: We demonstrated that increased pretreatment serum CRP level (${\geq}10mg/L$) was significantly associated with poor prognosis in gastric cancer patients, either in early or advanced stages.

Software Technology Integrated Smart Machine Tool Development for Mold Machining

De-Yu Park(박대유),Kyu-Yeong Yum(엄규용),Hyun-Yeong Cho(조현용),Du-Jin Kim(김두진),Jae-Keun Park(박재근),Su-Jin Kim(김수진) Korean Society for Precision Engineering 2018 한국정밀공학회지 Vol.35 No.2

Dynamic analysis for gene expression profiles of endothelial colony forming cells under hypoxia

De-Cai Yu,Wen-Du Feng,Xian-Biao Shi,hi-Yong Wang,Wei Ge,Chun-Ping Jiang,Xi-Tai Sun,Yi-Tao Ding 한국유전학회 2013 Genes & Genomics Vol.35 No.4

Previous studies have shown that endothelial colony forming cells (ECFCs) play an important role in the neovascularization of tumors. Hypoxia is emphasized as an important promoter of angiogenesis. However, little is known about genome-wide transcriptional regulation of ECFCs under hypoxic conditions. In this study, gene expression profiles in ECFCswere evaluated under hypoxic conditions for 3, 6, 12, 24,and 48 h, using Affymetrix U133 plus 2.0 chip microarray. 1,103 hypoxia-regulated genes were filtered, with 379(0.693 %) genes up-regulated and 724 (1.32 %) genes downregulated. Most of the up-regulated genes were involved in apoptosis, cell proliferation, or metabolic processes, while most of the down-regulated genes were involved in cell adherence,cell cycle,DNAandmRNAmetabolic processes,multi-cellular organism development, protein metabolic processes, response to stress, signal transduction, or transport. This expression profile is ECFC-specific, because it is significantly different from those of endothelial cells and smooth muscle cells under hypoxic conditions. Moreover, hypoxia-regulated apoptosis in ECFCs is mainly related with the mitochondrial pathway (p53-BAX-Caspase-9) and the death receptor pathway (FASCaspase-8-Caspase-3). MAPK pathway is activated in ECFCs under hypoxic conditions. The differentially expressed genes of ECFCs were identified under hypoxic conditions, and related with cell apoptosis, cell cycle and MAPK pathways, shedding light on the mechanism of angiogenesis.

Differentially Rice Protein Expression Between Rice Bran and Endosperm

( Ting-yu Chen ),( De-min Wu ),( Ji-jyun Lai ),( Chang-yue Li ),( Hui-fen Liao ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

Rice (Oryza sativa L.), the major staple food for more than 60% of the world’s population, offer nutritional and health-enhancing properties. Therefore, breeding of new rice species has been fueled by the rising interest in Asian, Latin cuisines, and many countries. In Asia, rice and rice-based ingredients also appeal to both consumers and processors due to their unique combination of taste, nutrition, texture, and biological properties. Proteins and starch in rice are the two major components in rice seed, with approximately 8 and 80%, respectively. Especially in traditional Asian diet, rice seed contributes to about 28-54% of the protein source. The major rice proteins, including structural, metabolic, protective, and storage proteins, serve as sources of nitrogen, sulfur, and carbon for several important physiological functions. In our previous study also demonstrated that rice protein prolamin activated human mononuclear cells to produce cytokines and enhance anti-leukemic immunity. The present study aimed to compare the differentially expression of rice proteins with bran and endosperm by 2-dimentional electrophoresis (2-DE) and mass spectrometric assay. Several protein spots in 2-DE gel with different expression were isolated and identified. The results showed that the major proteins were metabolic, transporter, storage, antioxidant, disease resistant, and development-related proteins. Further investigation to clarify the different manifestations and functions of these proteins might contribute to development of new rice varieties and breeding with unique features.

Evaluation and Adjustment Based on Broad Learning System for Small Signal Stability Analysis of Power System Integrated with Wind Farms

Yang Yu-De,Yao Wen-Jing,Yang Li-Zhen 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.6

This paper primarily focuses on evaluation and adjustment methods for small signal analysis with wind farm integration. The connection of wind farms may aff ect the original oscillation modes of the system, and may also introduce new oscillation modes. To ensure the security and stability of the system, it is necessary to assess the running state of the system and evaluate the development direction of the small signal stability on the premise of taking volatility into account. It is also important to fast adjust the system when an unstable state happened. The method in this paper provides a new way to accurately evaluate and adjust the stability of the system integrated with wind farms. Broad learning system (BLS) is a non-fi xed model and has the potential of incremental learning. A BLS model is trained to evaluate the damping ratio sensitivity in diff erent operating states. The adjustment part will use the optimal adjustment model and damping ratio sensitivity to adjust unstable systems. The superior performance of the model proposed in this paper is tested by the case study based on the IEEE 3-machine, 9-bus, and the New-England 10-machine, 39-bus. The results demonstrate the feasibility, validity, and eff ectiveness of the method proposed in this article.