One-Year Continuous Measurement of Outdoor Radon Progeny Concentration in Beijing Area

Zhang, Lei,Wang, Yunxiang,Guo, Qiuju The Korean Association for Radiation Protection 2020 방사선방어학회지 Vol.45 No.3

Background: Compared with reported data of radon concentration, data of radon progeny concentration is limited in general, especially in outdoor environment. Materials and Methods: To know both the level and the variation of radon progeny concentration in outdoor environment in Beijing area, one-year continuous measurement with a cycle of 60 minutes was carried out by a step-advanced filter (SAF) monitor for radon progeny measurement. The observation site was located in a park in Eastern Beijing area, and the observation period was from October 17, 2018 to September 29, 2019. Results and Discussion: The equivalent equilibrium concentration (EEC) of radon progeny varies from 0.7 to 19.1 Bq·m^-3, with an annual average of 4.9 ± 2.7 Bq·m^-3. A clear diurnal variation of EEC, higher in the early morning and lower in the late afternoon, is observed due to the high sensitivity of the SAF monitor. Conclusion: Vertical convection of atmospheric boundary layer is thought to be the main reason of this phenomenon. For annual variation, the lowest monthly average EEC appeared in April, while the highest appeared in November, which might attribute to the atmospheric stability in different seasons.

A Composite Index-based Approach for Hierarchical Assessment of Forest Ecosystem Health : An Example of Pinus tabulaeformis

Mingxia Zhang,Dexiang Wang,Zhao Xu,Qiuju Guo 보안공학연구지원센터 2014 International Journal of Multimedia and Ubiquitous Vol.9 No.7

A Method for Missing Data Recovery of Waste Gas Monitoring in Animal Building Based on GA-SVM

Jinming Liu,Qiuju Xie,Yuanyuan Zhang 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.5

In order to solve the data missing problem caused by sensor faults during the waste gas monitoring in animal building, a method for missing data recovery was presented based on support vector machine (SVM) combined with genetic algorithm (GA). Multiple factors that influence monitoring values of the waste gas in animal building such as temporal, spatial and environmental, were considered to established a SVM regression prediction model to estimate the missing data of the waste gas monitoring. Meanwhile, to obtain better prediction accuracy, model parameters were optimized by the GA. The data processing of the ammonia (NH3) concentration was taken as an example; monitoring data of 3 days were randomly selected in a farm to test the presented model in this paper. It is shown that there was a very little error between the estimated data and the monitoring data, the maximal relative error was 6.99 % (percent), and the average relative error was 2.15 % (percent). It is an effective method for missing data recovery and a practical way of data processing for waste gas monitoring in animal building.

ABE based Access Control with Authenticated Dynamic Policy Updating in Clouds

Liang-Ao Zhang,Xingming Sun,Zhihua Xia,Qiuju Ji 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.8

Attribute-Based Encryption (ABE) is a promising cryptographic primitive to implement access control for secure data storage in the cloud. Since the data owner may frequently change the access policies defined in the ciphertext, it is significant to provide the capacity for dynamic policy updating. However the cloud should also authenticate the owner because the adversary may modify the access policies of the files in the cloud to prevent the legal users from accessing them. In this paper, we focus on the owner’s authentication in the ABE systems and propose a novel scheme which enables access control with authenticated dynamic policy updating in the cloud. We adapt the Pedersen commitment and Zero Knowledge Proof of Knowledge (ZKPK) to realize the anonymous authentication of the owner’s policy updating key without increasing any secret information to the owner side. The analysis shows that our scheme is authentic and efficient as well as adaptive to different types of access policies.

Model-based Compensation and Pareto-optimal Trajectory Modification Method for Robotic Applications

Xiaoyan Chen,Qiuju Zhang,Yilin Sun 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.7

This study addresses the problem in accuracies of robot positioning and trajectory with compliance and geometric errors in robotic applications. A rigid–flexible coupling position error model of serial robot is presented to identify geometric and compliance error parameters simultaneously. On the basis of the error compensation model, the predicted position error can be corrected by the proposed hybrid error compensation method. Particular attention is paid to the deviation along the desired trajectory with respect to the corresponding updated trajectory, which is consecutively changing and cannot be corrected directly. A segmentation trajectory control method based on the Pareto-optimal with weighted-sum algorithm is proposed to solve the multi-objective optimisation problem in trajectory modification. The offline program optimiser integrates the proposed model-based compensation and trajectory modification method by MATLAB and VS software development platform. The method is developed to be an effective solution for the problem in absolute accuracies of positioning and trajectory with the experimental results achieved on a Staubli TX60L robot. Additional experiment is conducted with a Staubli RX160L robot to demonstrate the extensive feasibility and practical effectiveness of our approach for other industrial robots.

High-efficiency organic solar cells based on a small-molecule donor and a low-bandgap polymer acceptor with strong absorption

Yang, Yankang,Qiu, Beibei,Chen, Shanshan,Zhou, Qiuju,Peng, Ying,Zhang, Zhi-Guo,Yao, Jia,Luo, Zhenghui,Chen, Xiaofeng,Xue, Lingwei,Feng, Liuliu,Yang, Changduk,Li, Yongfang The Royal Society of Chemistry 2018 Journal of materials chemistry. A, Materials for e Vol.6 No.20

<P>Solution-processed organic solar cells (OSCs) have been attracting more and more attention for a series of well-known advantages, and power conversion efficiencies (PCEs) of over 11% have been reported. However, the highest PCE of the OSCs based on small molecule donor/polymer acceptor blends is only 4.82%, which was much lower than those of other types of OSCs due to weak absorption of the polymer acceptor and the unbalanced charge carrier mobility of the small molecule donor and the polymer acceptor. Here, we fabricated small molecule donor/polymer acceptor-based OSCs using the wide bandgap SM1 and DR3TBDTT as the small molecular donor and the low-bandgap n-type conjugated polymer PZ1 as the polymer acceptor. With the treatment of a solvent additive, which can promote the absorption intensity, enhance the carrier mobility and suppress the charge carrier recombination, the SM1-based devices and the DR3TBDTT-based devices show PCEs of 3.97% and 5.86%, respectively. It is worth mentioning that the PCE of 5.86% is the state-of-the-art efficiency for OSCs based on the small molecular donor/polymer acceptor system.</P>

Tie1 contributes to the development of ovarian hyperstimulation syndrome under the regulation of EGR1 in granulosa cells

Sun Lihua,Tian Hui,Xue Songguo,Ye Hongjuan,Xue Xue,Wang Rongxiang,Liu Yu,Zhang Caixia,Chen Qiuju,Gao Shaorong 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

The expression of tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 (Tie1), a transmembrane protein expressed almost exclusively by endothelial cells, has been reported in granulosa cells. However, its significance in ovarian hyperstimulation syndrome (OHSS), which can occur after the injection of gonadotropins in infertile women undergoing controlled ovarian stimulation, is unknown. Here, we report significantly increased Tie1 and vascular endothelial growth factor (VEGF) expression in cultured granulosa cells from OHSS patients, as well as ovaries from rats with experimentally established OHSS, compared to controls, with the levels of both proteins also increasing in granulosa and SVOG cells (a nontumorigenic human granulosa-lutein cell line) treated with an acute dose of human chorionic gonadotropin (hCG). Tie1 silencing abolished the hCG-induced VEGF level in SVOG cells and attenuated the progression of OHSS in rats, as determined by histological analysis. Further studies in SVOG cells revealed that the hCG-induced upregulation of Tie1 expression involved the phosphoinositide 3-kinase/protein kinase B signaling pathway. We also report that early growth response protein 1 (EGR1), whose expression was also upregulated by hCG, bound directly to the Tie1 promoter and activated its transcription. Taken together, our results indicate that Tie1 may be a therapeutic target in cases of moderate-to-severe OHSS. Further studies are needed to address its clinical relevance.