Experimental investigation on the propagation characteristics of pressure oscillation in direct contact condensation with low mass flux steam jet

Qiu, Binbin,Yang, Qingchuan,Yan, Junjie,li, Gen,Revankar, Shripad T. Elsevier 2017 Experimental thermal and fluid science Vol.88 No.-

<P><B>Abstract</B></P> <P>The propagation characteristics of pressure oscillation in direct contact condensation with low mass flux steam jet have been investigated experimentally. Steam is injected into subcooled water at one atmosphere pressure with steam mass flux and water temperature range of 186–272kg/(m<SUP>2</SUP> s) and 293–343K. The pressure oscillation propagates in the form of wave with stable dominant frequency, however the wave intensity attenuates with the increasing distance from the oscillation source. The root mean square of pressure wave <I>p</I> <SUB>rms</SUB> attenuates rapidly with the increasing dimensionless radial distance from the nozzle exit. At about dimensionless radial distance <I>R</I> =100, the <I>p</I> <SUB>rms</SUB> is attenuated by about 90%. Although the dominant frequency of the pressure oscillation is constant during the propagation, after <I>R</I> =100, there will be not enough energy for the pressure oscillation to resonate with relevant equipment. A correlation equation to calculate the root mean square of pressure oscillation along the radial distance is given. The prediction errors are within ±30% compared with the experimental data.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The pressure oscillation propagates in the form of wave. </LI> <LI> In the propagation process, the frequency remains the same but the intensity attenuates. </LI> <LI> A correlation to calculate the <I>p</I> <SUB>rms</SUB> along the radial distance is given. </LI> <LI> At about R=100, the <I>p</I> <SUB>rms</SUB> is attenuated by about 90% and most of the energy is dissipated. </LI> </UL> </P>

Cordblood-Based High-Throughput Screening for Deafness Gene of 646 Newborns in Jinan Area of China

Shou-Xia Li,Ding-Li Chen,Su-Bin Zhao,Li-Li Guo,Hai-Qin Feng,Xiao-Fang Zhang,Li-Li Ping,Zhi-Ming Yang,Cai-Xia Sun,Gen-Dong Yao 대한이비인후과학회 2015 Clinical and Experimental Otorhinolaryngology Vol.8 No.3

Objectives. Infants with slight/mild or late-onset hearing impairment might be missed in universal newborn hearing screening (UNHS). We identified the mutation hot spot of common deaf gene in the newborns in Jinan area population by screening the mutation spot with neonate cord blood, in order to make clear whether the neonate cord blood for screening is feasible. Methods. Six hundred and forty-six newborns were subjected to both UNHS and genetic screening for deafness by using neonate cord blood. The newborn genetic screening targeted four deafness-associated genes, which were commonly found in the Chinese population including gap junction beta-2 protein (GJB2), gap junction beta-3 protein (GJB3), solute carrier family 26 member 4 (SLC26A4), and mtDNA 12S rRNA. The most common 20 spot mutations in 4 deaf genes were detected by MassARRAY iPLEX platform and mitochondrial 12S rRNA A1555G and C1494T mutations were sequenced using Sanger sequencing. Results. Among the 646 newborns, 635 cases passed the UNHS and the other 11 cases (1.7%) did not. Of the 11 failures, two cases were found to carry homozygous GJB2 p.R143W pathogenic mutation, one case was found to have heterozygous GJB2 235delC mutation, and another one case carried heterozygous GJB3 p.R180X pathogenic mutation. Six hundred and thirty-five babies passed the newborn hearing screening, in which 25 babies were identified to carry pathogenic mutations, including 12 heterozygotes (1.9%) for GJB2 235delC, eight heterozygotes (1.3%) for SLC26A4 IVS7-2A>G, one heterozygote (0.2%) for p.R409H, two homozygotes (0.3%) for m.1494C>T, and two homozygotes (0.3%) for m.1555A>G. Conclusion. Newborn genetic screening through the umbilical cord blood for common deafness-associated mutations may identify carriers sensitive to aminoglycoside antibiotic, and can effectively prevent or delay hearing loss occurs.

MicroRNA-3200-5p Promotes Osteosarcoma Cell Invasion via Suppression of BRMS1

Li, Gen,Li, Li,Sun, Qi,Wu, Jiezhou,Ge, Wei,Lu, Guanghua,Cai, Ming Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.6

Tumour metastasis is one of the most serious challenges of cancer as it is the major cause of mortality in patients with solid tumours, including osteosarcoma (OS). In this regard, anti-metastatic genes have potential for metastasis inhibition strategies. Recent evidence showed the importance of breast cancer metastasis suppressor 1 (BRMS1) in control of OS invasiveness, but the regulation of BRMS1 in OS remains largely unknown. Here, we used bioinformatics analyses to predict BRMS1-targeting microRNAs (miRNAs), and the functional binding of miRNAs to BRMS1 mRNA was evaluated using a dual luciferase reporter assay. Among all BRMS1-targeting miRNAs, only miR-151b, miR-7-5p and miR-3200-5p showed significant expression in OS specimens. Specifically, we found that only miR-3200-5p significantly inhibited protein translation of BRMS1 via pairing to the 3'-UTR of the BRMS1 mRNA. Moreover, we detected significantly lower BRMS1 and significantly higher miR-3200-5p in the OS specimens compared to the paired adjacent non-tumour bone tissues. Furthermore, BRMS1 and miR-3200-5p levels were inversely correlated to each other. Low BRMS1 was correlated with metastasis and poor patient survival. In vitro, overexpression of miR-3200-5p significantly decreased BRMS1 levels and promoted OS cell invasion and migration, while depletion of miR-3200-5p significantly increased BRMS1 levels and inhibited OS cell invasion and migration. Thus, our study revealed that miR-3200-5p may be a critical regulator of OS cell invasiveness.

Current-voltage Characteristics of Ceramics with Positive Temperature Coefficient of Resistance

Li, Yong-Gen,Cho, Sung-Gurl The Korean Ceramic Society 2003 한국세라믹학회지 Vol.40 No.10

A current-voltage relation for Positive Temperature Coefficient of Resistance (PTCR) ceramic was derived and compared with the experimental data. The new current-voltage relation was developed based on Heywangs double Schottky barrier model and a bias distribution across the grain boundary. The voltage limitation V < 4${\Phi}$$\sub$b/ suggested by Heywang is no longer necessary in the new expression for the voltage dependence of the resistance. The pulsed voltages were applied to the PTCR ceramic specimen in order to avoid possible temperature variation during the measurement.

Will a Wiener Filter Decrease the Accuracy of HRTEM Displacement Measurements of Aperiodic Structures?

Gen Li,Dongsheng Song,Zhenyu Liao,Jing Zhu 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.12

Modern Cs-corrected high-resolution transmission electron microscopy (HRTEM) has pushed the resolution limit to sub-angstrom scale and has made possible the quantitative analyses of local aperiodic atomic structures. After images have been obtained, a Wiener filter is often used to improve the signal-to-noise ratio, especially for those samples containing both crystal and large amorphous components. However, a Wiener filter may introduce distortions in the original experimental images. From this point of view, having a fundamental understanding of the effect of a Wiener filter on the accuracy of atomic displacement measurements in aperiodic structures is important. In this work, we first review the principle of the Wiener filter and theoretically discuss the origin of the distortions induced in aperiodic structures by using a Wiener filter. Then, using hypothetical experimental systems that contains both aperiodic crystal structures and amorphous layers, we carried out synthetic experiments to quantitatively estimate the effect of the Wiener filter on the measurements of aperiodic displacements. Compared with the values for a non-filtered image, the signal-to-noise ratio was significantly improved, and the accuracy of the displacement measurement was not decreased when proper Wiener filter parameters were used. Such results are of great importance for the processing of HRTEM images.

Tracking moving objects by using a pan-tilt-zoom camera

GEN LI,Jae Kyu Suhr,Seung-In Noh,Jaihie Kim 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

This paper proposes a method of tracking a moving object using a Pan-Tilt-Zoom (PTZ) camera. For reliable tracking, a template matching technique is used to determine the location and size of the object to be tracked, and a background compensation technique is utilized for refining the template matching result and updating a new template.

Minimizing false detection of skin color by using background subtraction

Gen LI,Jae Kyu Suhr,Dongik Kim,Ho Gi Jung,Jaihie Kim 대한전자공학회 2010 ICEIC:International Conference on Electronics, Inf Vol.1 No.1

Detecting skin color from image sequences has played an important role in many computer vision applications, such as face detection and tracking. Even though there are a number of approaches for skin color detection, most of the existing algorithms produce false positives when non-skin pixels have similar color to skin color. To overcome this problem, this paper proposes a method that combines skin color detection with background subtraction. In experiment, we quantitatively evaluated three existing skin color detection methods with mixture of Gaussian-based background subtraction. Experimental results show that the proposed approach significantly reduces false positives.

3D Object Depth Extraction based on integral imaging

Gen Li,Dong-Choon Hwang,Keong-Jin Lee,Eun-Soo Kim 한국통신학회 2008 한국통신학회 학술대회논문집 Vol.2008 No.7

Numerical study of concrete-encased CFST under preload followed by sustained service load

Gen Li,Chao Hou,Lin-Hai Han,Luming Shen 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.1

Developed from conventional concrete filled steel tubular (CFST) members, concrete-encased CFST has attracted growing attention in building and bridge practices. In actual construction, the inner CFST is erected prior to the casting of the outer reinforced concrete part to support the construction preload, after which the whole composite member is under sustained service load. The complex loading sequence leads to highly nonlinear material interaction and consequently complicated structural performance. This paper studies the full-range behaviour of concrete-encased CFST columns with initial preload on inner CFST followed by sustained service load over the whole composite section. Validated against the reported data obtained from specifically designed tests, a finite element analysis model is developed to investigate the detailed structural behaviour in terms of ultimate strength, load distribution, material interaction and strain development. Parametric analysis is then carried out to evaluate the impact of significant factors on the structural behaviour of the composite columns. Finally, a simplified design method for estimating the sectional capacity of concrete-encased CFST is proposed, with the combined influences of construction preload and sustained service load being taken into account. The feasibility of the developed method is validated against both the test data and the simulation results.

Design and Implementation of a Network Attack Platform Based on Plug-in Technology

Li Gen,Wang Bailing,Liu Yang,Bai Xuefeng,Yuan Xinling 보안공학연구지원센터 2013 International Journal of Security and Its Applicat Vol.7 No.3