The Effect of Composition Change on Porosity in a Packed Bed on its Softening Process

Zheng Xiao Qin,Sang Min Choi(최상민) 한국연소학회 2008 KOSCOSYMPOSIUM논문집 Vol.- No.-

To understand structural change on softening and melting in the ore layers, the cold experimentation in the laboratory scale is conducted to simulate the effect of temperature, pressure and material composition on softening using cylindrical packed bed of wax particles. The particular study of the effect of composition change on cohesive layer is described in this paper. The cohesive layer is configured by sinter, pellet or lumpy ore. To simulate the bed composition change of the ironbearing materials, two types of wax packed bed are studied: a mixture bed (the 55-grade and 60-grade of wax balls are physically mixed to form the bed) and a blend bed (the two grades of wax are melted together to make the balls for the bed). The bed shrinkage behavior is mathematically described by creep deformation theory. It is found that a blend bed has a faster creep deformation rate than a mixture bed. Also the porosity reduction behavior of a packed bed is not a simple average of the individual components of the bed. Moreover, a mixture bed maintains a better porous structure than a blend bed under a given operational condition.

중국 출신 고학력 결혼이주여성들의 자녀 초등학교 선택에 관한 질적 사례연구

정친 ( Zheng Qin ) 대한가정학회 2024 Human Ecology Research(HER) Vol.62 No.1

This study aims to understand the experiences of highly educated married immigrant women from China, who hold a master's degree or higher, when selecting an elementary school for their children and to explore the significance of that experience. This study included eight participants, all of whom were married immigrant women who had resided in Korea for a minimum of five years. Data was collected through in-depth interviews, which were conducted over approximately one year, from June 2022 to August 2023. The study was approached as a case study. As a result of this study, the similarities between the cases were “choices based on charactercentered education and cultural convergence”, “choices for the child's future and career”, and “choices influenced by the primary caregiver's use of bilingualism”. The differences observed in the cases appeared in “choices based on the balance between global education ideals and economic realities”, “choices based on specialized curriculum content”, and “choices based on connections to higher-level schools”. This study is important, as it underscores the need to conduct various research initiatives on multinational immigrant women and their children. These findings suggest that the study can contribute to the development of multicultural policies that are grounded in the actual experiences and critical awareness of married Chinese immigrant women, who constitute a substantial part of Korean society.

Piezoelectric activities and domain patterns of orthorhombic Ba(Zr,Ti)O3 ceramics

P. Zheng,K.X. Song,H.B. Qin,L. Zheng,L.M. Zheng 한국물리학회 2013 Current Applied Physics Vol.13 No.6

Ba(ZrxTi1-x)O3 (0.025 ≤ x ≤ 0.065) ceramics were prepared by conventional solid-state reaction method. Crystalline structures were analyzed by X-ray diffraction. It was shown that all the Ba(ZrxTi1-x)O3(0.025 ≤ x ≤ 0.065) ceramics were of orthorhombic phase at room temperature. Piezoelectric activities and domain patterns were investigated and compared with those of BaTiO3 ceramic. All the Ba(ZrxTi1-x)O3 ceramics showed nearly the same d33 values of about 265 pC/N and the same domain width of about 220 nm. By comparing the grain sizes and domain width of the Ba(ZrxTi1-x)O3 ceramics with those of BaTiO3 ceramic, it is speculated that the variation of domain width with grain sizes in orthorhombic Ba(ZrxTi1-x)O3 ceramics may be different with that in tetragonal BaTiO3 ceramic. Besides domain width,the effective inertia mass of domain wall is also considered to be a very important factor that impacts the piezoelectric activities of the Ba(ZrxTi1-x)O3 ceramics.

화교 중고등학생의 문화적응 스트레스, -중국어 및 한국어 능력과학교적응과의 관련성-

정친 ( Zheng Qin ) 인문사회과학예술융합학회 2019 인문사회과학예술융합학회지 Vol.3 No.2

본 연구의 목적은 화교 중고등학생의 문화적응 스트레스, 중국어 및 한국어 능력, 학교적응의 전반적인 경향을 살펴보고, 문화적응 스트레스와 중국어 및 한국어 능력이 학교적응과관련이 있는지 알아보는 것이다. 화교 중고등학생의 문화적응 스트레스는 중국어 능력 압박,한국어 능력 압박, 한국문화적응 압박, 중국문화유지 압박의 하위영역으로 구성되며, 학교적응은 공부, 친구, 교사, 생활 차원의 적응으로 구성된다. 본 연구의 자료는 서울 및 인천 소재 화교 학교에 재학 중인 중고등학생으로부터 수집하였으며, 총 424명의 자료를 기술통계및 다중회귀분석을 사용하여 분석하였다. The objective of this research is to generally view the normal influence factors including acculturative stress, the ability of Chinese and Korean language and school adjustment of middle and high school students among overseas Chinese, and to find out whether there is the relatedness between acculturative stress, the ability of Chinese and Korean language and school adjustment. The acculturative stress of middle and high school students among overseas Chinese is comprised by the ability of Chinese, the ability of Korean, Korean acculturation, and Chinese cultural continuity. The adapting capability to school includes study, friend, teacher, and school life. The data of this research is based on the middle and high school students who are learning in Seoul and Incheon now. And totally 424 personal information is collected and analyzed by technical statistics and multiple regression analysis.

TC1 (C8orf4) is involved in ERK1/2 pathway-regulated G1-to S-phase transition

( Yi Dong Wang ),( Guo Hui Bian ),( Xiao Yan Lv ),( Rong Zheng ),( Huan Sun ),( Zheng Zhang ),( Ye Chen ),( Qin Wei Li ),( Yan Xiao ),( Qiu Tan Yang ),( Jian Zhong Ai ),( Yu Quan Wei ),( Qin Zhou ) 생화학분자생물학회 2008 BMB Reports Vol.41 No.10

INVESTIGATION OF EFFECTS OF COMPLEX AEROBATICS ON PLASMA LEVELS OF ACTH, LEUCINE-ENKEPHALIN AND NEUROTENSION IN PILOTS

Qin Shizhen,Zhou Zheng,Xu Langen,Zhang Xinhua 한국항공우주의학협회 1992 항공우주의학회지 Vol.2 No.2

A New Islanding Detection Method Based on Feature Recognition Technology

Zheng, Xinxin,Xiao, Lan,Qin, Wenwen,Zhang, Qing The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.2

Three-phase grid-connected inverters are widely applied in the fields of new energy power generation, electric vehicles and so on. Islanding detection is necessary to ensure the stability and safety of such systems. In this paper, feature recognition technology is applied and a novel islanding detection method is proposed. It can identify the features of inverter systems. The theoretical values of these features are defined as codebooks. The difference between the actual value of a feature and the codebook is defined as the quantizing distortion. When islanding happens, the sum of the quantizing distortions exceeds the threshold value. Thus, islanding can be detected. The non-detection zone can be avoided by choosing reasonable features. To accelerate the speed of detection and to avoid miscalculation, an active islanding detection method based on feature recognition technology is given. Compared to the active frequency or phase drift methods, the proposed active method can reduce the distortion of grid-current when the inverter works normally. The principles of the islanding detection method based on the feature recognition technology and the improved active method are both analyzed in detail. An 18 kVA DSP-based three-phase inverter with the SVPWM control strategy has been established and tested. Simulation and experimental results verify the theoretical analysis.

Common genetic determinants of breast-cancer risk in East Asian women: a collaborative study of 23 637 breast cancer cases and 25 579 controls

Zheng, Wei,Zhang, Ben,Cai, Qiuyin,Sung, Hyuna,Michailidou, Kyriaki,Shi, Jiajun,Choi, Ji-Yeob,Long, Jirong,Dennis, Joe,Humphreys, Manjeet K.,Wang, Qin,Lu, Wei,Gao, Yu-Tang,Li, Chun,Cai, Hui,Park, Sue K Oxford University Press 2013 Human Molecular Genetics Vol.22 No.12

<P>In a consortium including 23 637 breast cancer patients and 25 579 controls of East Asian ancestry, we investigated 70 single-nucleotide polymorphisms (SNPs) in 67 independent breast cancer susceptibility loci recently identified by genome-wide association studies (GWASs) conducted primarily in European-ancestry populations. SNPs in 31 loci showed an association with breast cancer risk at <I>P</I> < 0.05 in a direction consistent with that reported previously. Twenty-one of them remained statistically significant after adjusting for multiple comparisons with the Bonferroni-corrected significance level of <0.0015. Eight of the 70 SNPs showed a significantly different association with breast cancer risk by estrogen receptor (ER) status at <I>P</I> < 0.05. With the exception of rs2046210 at 6q25.1, the seven other SNPs showed a stronger association with ER-positive than ER-negative cancer. This study replicated all five genetic risk variants initially identified in Asians and provided evidence for associations of breast cancer risk in the East Asian population with nearly half of the genetic risk variants initially reported in GWASs conducted in European descendants. Taken together, these common genetic risk variants explain ∼10% of excess familial risk of breast cancer in Asian populations.</P>

Influence of random road excitation on DCT vehicle dynamic characteristics during starting and shifting

Zheng Guo,Datong Qin,Antai Li,Jihao Feng,Yonggang Liu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.9

Road excitation is the basic input of vehicle vibration, which greatly impacts on vehicle ride comfort. In addition, it can cause vertical vibration of the vehicle, leading to deformation of the powertrain mount. Similarly, the longitudinal movement of the powertrain can also cause deformation of the powertrain mount. Due to the effect of the powertrain mount, there is a mutual coupling between the vehicle in the longitudinal and vertical directions, which has a great influence on the smoothness and comfort of the vehicle. In order to reveal the impact of random road excitation on the vehicle dynamic characteristics of a dual clutch transmission (DCT) vehicle under starting and shifting conditions, a longitudinal-vertical coupled dynamic model of the DCT vehicle considering the powertrain mount was established. This model includes dynamic torque model of the engine, powertrain mount model, transmission system model, tire model and road excitation model. The influence of random road excitation on the vehicle’s dynamic characteristics is analyzed under starting, shifting, and different starting and shifting intentions. The simulation results of the longitudinal-vertical coupling dynamic DCT vehicle model considering road excitation are compared with vehicle test results, the model is found to accurately reflect the influence of road excitation on the dynamic performance of DCT vehicles under starting and shifting conditions, thus verifying the correctness of the model.

Prostate-specific Antigen Velocity (PSAV) and PSAV per Initial Volume (PSAVD) for Early Detection of Prostate Cancer in Chinese Men

Zheng, Xiang-Yi,Zhang, Peng,Xie, Li-Ping,You, Qi-Han,Cai, Bo-Sen,Qin, Jie Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.11

Aim: To investigate the utility of prostate-specific antigen velocity (PSAV) and PSAV per initial volume (PSAVD) for early detection of prostate cancer (PCa) in Chinese men. Methods: Between January 2009 and June 2012, a total of 193 men (aged 49-84 years, median 67 years) with at least 2 transrectal ultrasonography (TRUS) procedures and concurrent serum PSA measurements underwent prostate biopsy because of suspicion of PCa. The total group were classified into PCa and non-PCa groups, and the variables of the two groups were compared. Univariate and multivariate analyses were used to investigate which variables were predictove. The diagnostic values of PSAV, PSAVD and prostate-specific antigen density (PSAD) were compared using receiver operating characteristic (ROC) analysis. Results: Prostate cancer was diagnosed in 44 (22.8%) of the 193 men. There were significant differences between the groups in last and initial prostate volumes determined by TRUS, initial age, last serum PSA levels, PSAV, PSAD and PSAVD. After adjusting for confounding factors, the odds ratios of PCa across the quartile of PSAVD were 1, 4.06, 10.6, and 18.9 (P for trend <0.001).The area under the ROC curves (AUCs) of PSAD (0.779) and PSAVD (0.776) were similar and both significantly greater than that of PSA (AUC 0.667). PSAVD was a significantly better indicator of PCa than PSAV (AUC 0.736). There was no statistical significant difference between the AUC of PSAV and that of last serum PSA level. The sensitivity and specificity of PSAVD at a cutoff of 0.023ng in participants with last serum PSA levels of 4.0ng/mL-10.0ng was 73.7% and 70.7%, respectively. Conclusions: The results of this study demonstrated PSAVD may be a useful tool in PCa detection, especially in those undergoing previous TRUS examination.