A Preventive Maintenance Scheduling Problem with Random Interval Time

Qian Qian Zhao,Won Young Yun,Alfonsus Julanto Endharta 한국경영과학회 2018 한국경영과학회 학술대회논문집 Vol.2018 No.04

Determining Inspection Intervals for One-shot Systems with Support Equipments

Qian Qian Zhao,Won Young Yun 대한산업공학회 2015 대한산업공학회 추계학술대회논문집 Vol.2015 No.11

In this paper, we consider one-shot systems comprise one-shot devices and support equipments. The one-shot devices are stored for long periods of time, and its failure is detected only upon inspection. Support equipments are necessary for the operation of one-shot devices, and are maintained immediately upon failure. This paper deals with an inspection schedule problem for one-shot systems with support equipment and limited maintenance resources. Interval availability and life cycle costs are used as optimization criteria, and are estimated by simulation. Therefore, we aim to determine near-optimal inspection intervals of one-shot systems that minimize the expected life cycle cost and satisfy the target interval availability during inspection periods. An estimation of distribution algorithm (EDA) is proposed to find near-optimal solutions, and numerical examples are studied to investigate the effects of various model parameters.

디지털 기업에서 직무 자율성이 팀 성과에 미치는 영향 연구

Qianli Zhao,장경풍 인문사회 21 2022 인문사회 21 Vol.13 No.3

Research on the Influence of Job Autonomyon Team Performance in Digital EnterprisesQianli Zhao & Qingfeng Zhang Abstract: In order to enhance work motivation and personal interests for new generation of employees, it is important to support job autonomy and effectively improve team performance, so as to strengthen the competitive advantage of digital enterprises. This paper conducted a multi-stage and multi-regional questionnaire survey with 300 participants in digital enterprises. We have used SPSS 25.0 and AMOS 24.0 for linear regression analyses and intermediary effect test. Based on organization learning theory, the empirical results show that job autonomy has the significant positive effect on team performance in digital enterprises. The learning organization and flexible working schedule play mediating roles in this influence relationship. Future research should further explore the moderating variables to further enrich the theoretical model and research results. Key Words: Job Autonomy, Team Performance, Digital Enterprises, Learning Organization, Flexible Working Schedule Research on the Influence of Job Autonomy on Team Performance in Digital Enterprises Qianli Zhao & Qingfeng Zhang Abstract: In order to enhance work motivation and personal interests for new generation of employees, it is important to support job autonomy and effectively improve team performance, so as to strengthen the competitive advantage of digital enterprises. This paper conducted a multi-stage and multi-regional questionnaire survey with 300 participants in digital enterprises. We have used SPSS 25.0 and AMOS 24.0 for linear regression analyses and intermediary effect test. Based on organization learning theory, the empirical results show that job autonomy has the significant positive effect on team performance in digital enterprises. The learning organization and flexible working schedule play mediating roles in this influence relationship. Future research should further explore the moderating variables to further enrich the theoretical model and research results. Key Words: Job Autonomy, Team Performance, Digital Enterprises, Learning Organization, Flexible Working Schedule

A Preventive Maintenance Scheduling Problem with Random Interval Time

Qian Qian Zhao,Won Young Yun,Alfonsus Julanto Endharta 대한산업공학회 2018 대한산업공학회 춘계학술대회논문집 Vol.2018 No.4

Performance of the R-way Colposcopic Evaluation System in Cervical Cancer Screening

Zhao, Jian,Zhang, Xi,Chen, Rui,Zhao, Yu-Qian,Wang, Ting-Ting,He, Shan,Qiao, You-Lin Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Objective: To investigate the diagnostic value of the R-way colposcopic evaluation system (R-way system) in cervical cancer screening. Materials and Methods: Between August 2013 and August 2014, a total of 1,059 cases referred to colposcopy in Peking University First Hospital were studied using both the R-way system and conventional colposcopy. Our study evaluated and compared the diagnostic ability of the two methods in detecting high-grade lesions and cervical cancer (hereinafter called CIN2+). Evaluation indicators including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), Youden index and the area under the curve (AUC) of the receiver operating characteristic (ROC) were calculated. Results: The R-way system had a slightly lower specificity (94.5%) than conventional colposcopy (96.0%) for CIN2+ detection (P=0.181). However, the sensitivity (77.8%) was significantly higher than with the conventional colposcopic method (46.6%) (${\chi}^2=64.351$, P<0.001). In addition, the AUC of the ROC for CIN2+ detection using the R-way system (0.839) was larger than that with conventional colposcopy (0.731) (Z=4.348, P<0.001). If preliminary result had been drawn from cervical exfoliated cytology before colposcopy referral, combination of the R-way system with cytology could increase the sensitivity to 93.9% for CIN2+ detection (excluding ASCUS\LSIL), confirmed by multipoint biopsy or ECC. Conclusions: The diagnostic value of the R-way evaluation system is higher than that of conventional colposcopic evaluation in cervical cancer screening. Moreover, taking the ease of use and standardized quality control management into account, the R-way system is highly preferable.

Microstructure Change of Nanosilica-Cement Composites Partially Exposed to Sulfate Attack

Qian Huang,Liang Zhao,Chenggong Zhao,Dongsheng Liu,Chaoqiang Wang 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.3

The deterioration of cement composites containing nanosilica partially exposed to sulfate attack was studied, and the microstructure change of the composites was analysed by a scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results showed that nanosilica-cement composites had better sulfate resistance compared to plain cement composite under partial exposure to sulfate attack, and their sulfate resistance increased as the nanosilica content increased (in the range of 0 to 5 wt% replacing cement by weight). The main sulfate products were gypsum and ettringite within the surface and inner parts, respectively in both the immersed and evaporation portions of the nanosilica-cement composites, which was consistent with the plain cement composite. Thus, the incorporation of nanosilica did not change the distribution characteristics of the sulfate products within the composites partially exposed to sulfate attack. However, the addition of nanosilica reduced the amount of sulfate products in both the immersed and evaporation portions, and their amount decreased with the increase of nanosilica content. The evaporation portions of the composites suffered chemical sulfate attack rather than sulfate salt crystallization. Nanosilica-cement composites could be applied in real partial exposure environments containing sulfate ions.

Synthesis of multi-wall carbon nanotubes by Ni-substituted (loading) MCM-41 mesoporous molecular sieve catalyzed pyrolysis of ethanol

Qian Zhao,Tingshun Jiang,Changsheng Li,Hengbo Yin 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.2

Ni-loading MCM-41 mesoporous molecular sieve (Ni/MCM-41) and Ni-substituted MCM-41 mesoporous molecular sieve (Ni-MCM-41) were synthesized by wet impregnation method and hydrothermal method, respectively. Their mesoporous structures were evaluated by X-ray diffraction (XRD) and N2physical adsorption technique. Chemical vapor deposition (CVD) was employed to catalytically synthesize carbon nanotubes (CNTs) using Ni-MCM-41 or Ni/MCM-41 as catalyst via pyrolysis of ethanol at atmospheric pressure and 700 8C. The resulting carbon nanotubes were characterized by means of transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM)and Raman spectroscopy, respectively. The results show that the multi-wall carbon nanotubes (MWCNTs) were successfully obtained at 700 8C utilizing NiMCM-41 (or Ni/MCM-41) as a catalytic template by the pyrolysis of ethanol. MWCNTs obtained over Ni-MCM-41 catalyst have uniform diameter and high quality. On the other hand, the technique has great advantages such as low cost and easy operation for the preparation of carbon nanotubes.

Chinese Localization of Musicals Co-developed by Korea and China: A Case Study on the Musicals “Bachelor’s Vegetable Store”, “In the Mood for Sorrow”, and “Rimbaud”

Qian Zhao,방수경 사단법인 미래융합기술연구학회 2020 아시아태평양융합연구교류논문지 Vol.6 No.9

In previous years, China was behind the development among global musicals. Thus, more collaborative projects between China and Korea emerged. The musical market in China needed cross-border copyright collaboration because to diversify its repertoires and subjects, while the Korean musical companies demanded export copyrights of their musicals to overseas especially the Chinese market. Considering the supply and demand in the Chinese and Korean musical markets, this study selected three forms of collaborative projects in China. They include the Korean authorized musical “Bachelor’s Vegetable Store” (2019), the Chinese musical “In the Mood for Sorrow” (2018), and the musical “Rimbaud” (2018), which were all co-produced by the Chinese and Korean teams. Using the three forms of collaborative projects, this study analyzed four perspectives including the overview of the project overview of the project, preliminary preparation of the project, the production plan of localization, and the development strategy of cultural contents. Results showed that the advantages of the three forms of collaboration were as follows: for Korean authorized musicals co-produced by Chinese and Korean teams, the authorized company could evaluate the market value and future income of the musical in advance, and the production cycle was short; for original Chinese musicals co-created by Chinese and Korean teams and musicals co-produced by Chinese and Korean teams, the Korean companies had high project participation and diversified forms of revenue. The disadvantages of the three forms of cooperation, by contrast, were as follows: for Korean authorized musicals co-produced by Chinese and Korean teams, the copyright owners had low participation, single form of revenue and high uncontrollability of script adaptations; for Chinese original musicals co-created by Chinese and Korean teams, the cost of early development was high and the production cycle was long; for musicals co-produced by Chinese and Korean teams, the overall cost of the projects was high and the payback period was long. The analysis of the advantages and disadvantages of the three different forms of cooperation could be taken as a useful reference for the development strategy of musical localization in China.

Effect of carbon nanotube addition on friction coefficient of nanotubes/hydroxyapatite composites

Qian Zhao,Yalong Shen,Meiru Ji,Lei Zhang,Tingshun Jiang,Cangsheng Li 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.2

Carbon nanotubes/hydroxyapatite (CNTs/HA) composites with different CNTs contents were synthe-sized by in situ method and were characterized by XRD, TEM and Raman spectroscopy. Frictioncoefficients of the composites were tested using UMT-2 friction tester. Effect of various factors includingCNTs content, testing time and applied load on friction coefficient was carried out. Results show that theCNTs/HA composites exhibited lower friction coefficient than pure HA and their friction coefficientsdecreased with increase of CNTs content from 0 to 20 wt.%. Addition of CNTs in composite is beneficial toincrease wear resistance of the CNTs/HA composite and to decrease its friction coefficient.

Stochastic MAC-layer Interference Model for Opportunistic Spectrum Access: A Weighted Graphical Game Approach

Qian Zhao,Liang Shen,Cheng Ding 한국통신학회 2016 Journal of communications and networks Vol.18 No.3

This article investigates the problem of distributed channelselection in opportunistic spectrum access networks from aperspective of interference minimization. The traditional physical(PHY)-layer interference model is for information theoretic analysis. When practical multiple access mechanisms are considered,the recently developed binary medium access control (MAC)-layerinterference model in the previous work is more useful, in whichthe experienced interference of a user is defined as the numberof competing users. However, the binary model is not accurate inmathematics analysis with poor achievable performance. Therefore,we propose a real-valued one called stochastic MAC-layer interferencemodel, where the utility of a player is defined as a functionof the aggregate weight of the stochastic interference of competingneighbors. Then, the distributed channel selection problemin the stochastic MAC-layer interference model is formulated asa weighted stochastic MAC-layer interference minimization gameand we proved that the game is an exact potential game which existsone pure strategy Nash equilibrium point at least. By using theproposed stochastic learning-automata based uncoupled algorithmwith heterogeneous learning parameter (SLA-H), we can achievesuboptimal convergence averagely and this result can be verified inthe simulation. Moreover, the simulated results also prove that theproposed stochastic model can achieve higher throughput performanceand faster convergence behavior than the binary one.