NUMERICAL SIMULATION OF SYNOPTIC CONDITION ON A SEVERE SAND DUST STORM

JIANG, XUE-GONG,SHEN, JIAN-GUO,LIU, JING-TAO,CHUNG, YONG-SEUNG 한국교원대학교 환경과학연구소 2004 환경연구논문집 Vol.- No.8

By using observational data and MM5, an observational analysis and numerical study was conducted on the synoptic condition of a severe dust storm that was caused by a Mongolian cyclone which occurred from 6 to 8 April 2001. Results illustrated that the cyclogenesis was due to the isentropic potential voiticity (IPV) advection in the upper troposphere and the terrain modified baroclinicity in the mid-lower troposphere. The Altai-Sayan complex of mountains blocked the lower level cold air and made the isentropic surface sharply sleep. When the air slid down along the isentropic surface the increasing of baroclinicity and decreasing of stability blew up the vertical voiticity development. The formation of the dust storm was a result of a cyclonic cold front passing across the area. The occurrence of this dust storm was closely related to the strong surface wind, which was accompanied by a cold front passing, rather than the cyclogenesis, itself. Hence, the reason for the pre-front dust stonn formulation was the formation of heating convection. Reasons behind the formation of a black storm (visibility lower than 50 m), which occurred in the mid-north part of Inner Mongolia, lay in several aspects. Firstly, in this area the surface wind was strong, a direct result of the downward transport in mid-lower troposphere. Secondly, the cold front passed over the effected area near sunset so the air obtained much more surface heating to form a deeper mixed layer (ML). Thirdly, cooperation between the lower level wind and the terrain made the atmosphere in this area and acquired the maximum advective contribution necessary to form a deep post-front ML. The sensitivity experiment revealed that surface heal flux was important to the frontal lifting. In addition, the forcing of surface heating was also seen as the primary forcing mechanism of frontogenesis. Meanwhile, removal of the surface heat flux made the atmospheric stratification became stable and the pre-storm ML very shallow, which weakened the strength of the dust storm.

Universal transport properties of a quantum dot system with a laterally-coupled Majorana zero mode

Wei-Jiang Gong,Ying Zhao,Zhen Gao,Shu-Feng Zhang 한국물리학회 2015 Current Applied Physics Vol.15 No.4

We present a comprehensive analysis about the transport properties of a quantum dot (QD) system with a side-coupled Majorana zero mode. Our calculation result shows that when the coupling manners between the two leads and QDs are identical, the local Andreev reflection and the interlead normal tunneling have the same magnitude at the zero-bias limit. Accordingly, the zero-bias conductance value is always equal to e2/2h, which is exactly one half of the resonant-tunneling conductance. This result is independent of the level number and the level distribution in the single-QD case, and in the coupled-QD case it is irrelevant to the geometry of the QD molecule. The universal transport property is a powerful evidence for the feasibility to detect the MBSs based on a QD circuit. This result also means that the QD condition is not a key factor to achieve the detection. On the other hand, if the decoupling phenomenon appears, the Majorana zero mode may play a trivial role in contributing to the conductance property.

Influence of Majorana doublet on transport through a quantum dot system with ferromagnetic leads

Wei-Jiang Gong,Zhen Gao,Xiao-Qi Wang 한국물리학회 2015 Current Applied Physics Vol.15 No.10

We investigate the electron transport through a quantum dot connected with two ferromagnetic leads, by coupling one Majorana doublet laterally to the quantum dot. It is found that Majorana doublet keeps the value of zero-bias conductance to be independent of the shift of structural parameters, including dot level, relative lead-magnetization direction, and magnetic field on the dot. Even in the cases of asymmetric dot-lead couplings, the zero-bias conductance is weakly dependent on the relative leadmagnetization direction. On the other hand, when Majorana doublet is replaced by Majorana singlet, the zero-bias conductance value becomes sensitive to the structural parameters. Via analyzing the respective particle motion processes, the different influences of Majorana doublet and singlet are explained. We believe that this work can be helpful for understanding the peculiar properties of Majorana doublet.

Andreev reflections in a Y-shaped junction with Majorana zero mode

Wei-Jiang Gong,Xiao-Qi Wang,Guang-Yu Yi,Yu Han 한국물리학회 2016 Current Applied Physics Vol.16 No.7

We investigate the Andreev transports through a double-dot Y-shaped junction with Majorana zero mode. It is observed that the additional direct coupling between the dots plays a nontrivial role in manipulating the Andreev transports. Due to its existence, finite magnetic flux can be introduced through this structure to adjust the local and crossed Andreev reflections in different ways. As a result, changing the interdot coupling is able to enhance the crossed Andreev reflection and weaken the local one at the same time in both the linear and nonlinear transport regions. Such a work can be helpful for controlling the Andreev transport behaviors related to Majorana bound state.

Impurities-contributed abnormal thermoelectric effect in a parallel double quantum dot structure

Wei-Jiang Gong,Hui-Min Wang,Yu Han,Si-Jing Zhang 한국물리학회 2014 Current Applied Physics Vol.14 No.1

We discuss the influence of local impurities on the thermoelectric effect in a parallel double quantum dot (QD) structure. It is first found that in this structure, the Fano effect contributes significantly to the enhancement of thermoelectric efficiency, especially in the case of f ¼ p. Next, impurities are introduced to couple to the QDs, respectively. We readily find that regardless of which QD is coupled to a local impurity, the thermoelectric efficiency can be enhanced by the strengthening of impurityeQD coupling. This means that the destruction of the Fano interference is not the necessary condition to suppress the thermoelectric effect. Accordingly, we hope that the numerical results can help to understand the role of impurities in adjusting the thermoelectric properties of the QD structure.

Evaluation and Prediction on the Hydraulic Abrasion Performance of High Belite Cement-Based Concrete

Chunmeng Jiang,Linhua Jiang,Cheng Chen,Jingwei Gong,Shuangxi Li 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.6

High belite cement (HBC) concrete is increasingly applied to the hydraulic projects, where much attention should be paid to the abrasion performance. In this paper, the mass loss, abrasion rate and morphology indexes such as depth of abrasion, volume loss and fractal dimension of HBC-based concrete at different wear periods were determined through underwater method. Moreover, a new method by transforming the survey area of worn surface was put forward to simulating practical erosion conditions, based on which, the abrasion performance prediction model was built by Projection Pursuit Regression (PPR) theory. Results show that the compounding addition of 30% mineral admixtures had little contribution to the abrasion resistance of HBC concrete after being long-term cured, while reducing water-binder (w/b) ratios was still an effective way for improving that. The worn surface of concrete specimens was divided into three regions for abrade zone, transitional zone and sound zone, and the abrasion evolution was found to be related to the wear duration and space position. Furthermore, there were good correlations between mass loss rate, depth of abrasion, volume loss and fractal dimension, and the fitting formulas were also proposed with good coefficients. Eventually, the PPR model based on the data of transformed survey area was proved to be a promising approach for predicting the abrasion performance.

중국 소비자의 미리 포장된 식사 구매 의도에 대한 이론적 기반 및 실증적 검증: 소비자 혁신성 관점에서 확장된 TPB 모델

Hao-Jie Jiang,Chi Gong,Shuai Jiang 사회혁신기업연구원 2024 혁신기업연구 Vol.9 No.1

COVID-19 팬데믹의 영향으로 중국의 미리 포장된 식사 산업이 빠른 성장 단계에 진입하여 소비자들로부터 점점 더 많은 호감을 얻고 있습니다. 이 연구는 중국 소비자들이 미리 포장된 식사를 구매하는 데 영향을 미치는 요인을 탐색하는 것을 목표로 합니다. 우리는 계획된 행동 이론(TPB)과 소비자 혁신성을 사용하여 구조방정식 모델을 구축했습니다. 이 정량적 연구는 비확률 샘플링 온라인 설문조사를 통해 293개의 유효 데이터 포인트를 수집하고 SPSS 27.0 및 AMOS 26.0을 사용하여 모델 검증을 수행했습니다. 결과는 소비자의 도구적 및 정서적 태도가 구매 의도에 중요하게 긍정적인 영향을 미친다는 것을 보여줍니다. 서술적 규범도 구매 의도에 중요한 긍정적인 영향을 미칩니다, 반면 지시적 규범은 중요한 영향을 보이지 않습니다. 소비자의 자기 통제력과 외부 조건은 모두 구매 의도와 행동에 중요한 긍정적인 영향을 미칩니다. 구매 의도는 구매 행동에 중요한 영향을 미치며 자기 통제력과 외부 조건에서의 매개 효과를 가집니다. 소비자 혁신성은 구매 의도와 행동 사이에서 중요한 조절 역할을 합니다. 제품 디자인과 홍보를 강화하기 위해 소비자들에게 매력을 높이는 것이 필수적입니다. 추가 연구를 위한 제안이 제시됩니다. Owing to the impact of the COVID-19 pandemic, the pre-made food industry in China has entered a rapid growth phase, gaining increasing favor from consumers. This study aims to explore the factors influencing Chinese consumers' purchase of pre-made food. We employed the Theory of Planned Behavior (TPB) and consumer innovativeness to construct a structural equation model. This quantitative study gathered 293 valid data points through non-probability sampling online surveys and employed SPSS 27.0 and AMOS 26.0 for model validation. Results reveal that consumers' instrumental and affective attitudes significantly positively influence purchase intention. Descriptive norms also exert a significant positive impact on purchase intention, while injunctive norms do not show a significant effect. Consumers' self-control and external conditions both have significant positive influences on purchase intention and behavior. Purchase intention significantly affects purchase behavior and mediates effects in self-control and external conditions. Consumer innovativeness plays a significant moderating role between purchase intention and behavior. To enhance product design and promotion, it is imperative to increase attractiveness to consumers. Suggestions for further research are presented.

Synthesis of metal organic framework (MOF-5) with high selectivity for CO2/N2 separation in flue gas by maximum water concentration approach

Gong-Ying Wang,Zhiyong Deng,Ning Jiang,Shaoying Liu,Cong-Ming Tang 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.9

Water plays a crucial role in the synthesis mechanism of metal organic framework-5 (MOF-5). Synthesized MOF-5 with good phase structure and large specific surface area is largely determined by an important synthesis factor: the total water concentration of the initial synthesis solution (Ctw). An understanding of the effects of different and high Ctw on the synthesis of MOF-5 and the investigation of the maximum Ctw suitable for the synthesis of MOF-5 are important to guide the synthesis of MOF-5. Through the research of the maximum Ctw, a favorable synthetic approach was established which could realize the synthesis of MOF-5 with fine performance on CO2 adsorption and separation. The research results show that the maximum Ctw could be as high as 1,440mmol/L, and synthesized MOF- 5 still has a good phase structure and a large specific surface area of 2,136m2/g (BET). Synthesized MOF-5 by the maximum Ctw exhibits a high CO2 adsorption capacity of 2.5mmol/g and a low N2 adsorption capacity of 0.2mmol/g at 298 K and 100 kPa. More importantly, synthesized MOF-5 by the maximum Ctw exhibits a high selectivity for CO2/N2 of 18-22 at 298 K and 20-130 kPa in simulated flue gas.

A Study on the Influence of Personality Traits of College Students on the Way of Coping with Employment Stress and Entrepreneurial Intention in the Post-Epidemic Era

Jiang-Bo Yan,Ya-Li Fang,Chi Gong 사회혁신기업연구원 2023 혁신기업연구 Vol.8 No.2

With the arrival of the "post-epidemic era", the impact of multiple factors such as the epidemic and domestic and foreign economic weakness on the employment and entrepreneurship of graduates is still continuing and deepening, and youth employment has become a worldwide problem. Self-employment has gradually become a new employment channel, and self-employment of college students not only provides a large number of new jobs for the society, but also helps to alleviate the social employment pressure and the severe employment situation of college students. At present, exploring the factors influencing college students' entrepreneurial intention has become a hot topic in the field of entrepreneurship research. In this study, it is important to study the mechanism of each factor by constructing a model of the influencing factors of college students' entrepreneurial intention. The main conclusions from the study are as follows. First, all four personality traits have a significant positive influence on entrepreneurial intention, and college students with the above personality traits are more likely to have entrepreneurial intention, and the way of coping with employment pressure plays a mediating role in the relationship between personality traits and entrepreneurial intention. Based on this, the study provides valuable theoretical implications for research in this area and practical implications for how schools can improve students' entrepreneurial awareness.

Adenovirus-mediated Expression of Both Antisense Ornithine Decarboxylase and S-adenosylmethionine Decarboxylase Induces G₁ Arrest in HT-29 Cells

Gong, Lei,Jiang, Chunying,Zhang, Bing,Hu, Haiyan,Wang, Wei,Liu, Xianxi Korean Society for Biochemistry and Molecular Biol 2006 Journal of biochemistry and molecular biology Vol.39 No.6

To evaluated the effect of recombinant adenovirus Ad-ODC-AdoMetDCas which can simultaneously express both antisense ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC) on cell cycle distribution in colorectal cancer cell and investigated underlying regulatory responses, human colorectal cancer cells HT-29 were cultured in RPMI 1640 medium and infected with Ad-ODC-AdoMetDCas. Cell cycle progression was detected by flow cytometry analysis. The expression levels of cell cycle regulated proteins were measured by Western blot analysis. The mRNA level of cyclin D1 was measured by RT-PCR. And a luciferase reporter plasmid of cyclin D1 promoter was constructed to observe the effect of Ad-ODC-AdoMetDCas on cyclin D1 promoter activity. The results showed that recombinant adenovirus Ad-ODC-AdoMetDCas significantly induced $G_1$ arrest, decreased levels of cyclin D1 protein and mRNA and suppressed the promoter activity. Ad-ODC-AdoMetDCas also inhibited nuclear translocation of $\beta$-catenin. In conclusion, downregulation of ODC and AdoMetDC mediated by Ad-ODC-AdoMetDCas transfection induces $G_1$ arrest in HT-29 cells and the arrest was associated with suppression of cyclin D1 expression and inhibition of $\beta$-catenin nuclear translocation. As a new anticancer reagent, the recombinant adenovirus Ad-ODC-AdoMetDCas holds promising hope for the therapy of colorectal cancers.