Real-Time Prediction Model for Infrared Characteristics of Turbofan Engine

Ming Chen,Haoying Chen,Haibo Zhang,Jiayi Luo 한국항공우주학회 2022 International Journal of Aeronautical and Space Sc Vol.23 No.5

To improve the infrared stealth performance of the engine, an infrared characteristics real-time prediction model suitable for the overall design/control system simulation of small bypass ratio turbofan engine with typical exhaust system structure was developed. First, the accuracy and calculation speed of the model was proved to meet the requirements after comparing with CFD results; Then, the influence of the cycle parameters on the infrared characteristics was analyzed by the model. Steady-state numerical simulations were carried out for different flight missions, and the variation law of the engine infrared characteristics in the flight envelope was obtained. Finally, the dynamic response of infrared characteristics in transient state was studied. The results show that the infrared radiation intensity in the afterburner state increased by 1–2 orders of magnitude compared with the cruise state; The response speed of lateral infrared radiation intensity was basically consistent with that of thrust, while the response of backward infrared radiation intensity lagged greatly. Some useful implications from this study include turbofan overall optimized design and performance seeking control.

Comparison of the Distribution Pattern of 21-Gene Recurrence Score between Mucinous Breast Cancer and Infiltrating Ductal Carcinoma in Chinese Population: A Retrospective Single-Center Study

Jiayi Wu,Shuning Ding,Linling Yin,Xiaochun Fei,Caijin Lin,Lisa Andriani,Chihwan Goh,Jiahui Huang,Jin Hong,Weiqi Gao,Siji Zhu,Hui Wang,Ou Huang,Xiaosong Chen,Jianrong He,Yafen Li,Kunwei Shen,Weiguo Che 대한암학회 2020 Cancer Research and Treatment Vol.52 No.3

Purpose This retrospective study aimed to evaluate the distribution pattern and prognostic value of 21-gene recurrence score (RS) in Chinese patients with mucinous breast cancer (MC) and compared with infiltrating ductal carcinoma (IDC). Materials and Methods Patients diagnosed with MC or IDC from January 2010 to January 2017 were retrospectively recruited. Reverse transcriptase–polymerase chain reaction assay of 21 genes was conducted to calculate the RS. Univariate and multivariate analyses were performed to assess the association between RS and clinicopathological factors. Survival outcomes including disease-free survival (DFS) and overall survival (OS) were estimated by Kaplan-Meier method and compared by log-rank test. Results The MC cohort included 128 patients and the IDC cohort included 707 patients. The proportions of patients with a low (RS < 18), intermediate (18-30), or high risk (RS > 30) were 32.0%, 48.4%, and 19.5% in MC cohort, and 26.9%, 46.8% and 26.3% in IDC cohort. The distribution of RS varied significantly according to different Ki-67 index and molecular subtype in both cohorts. Moreover, the receipt of chemotherapy was associated with RS in both cohorts. Among patients with MC, tumor stage was related to the DFS (p=0.040). No significant differences in DFS and OS were found among MC patients in different RS risk groups (OS, p=0.695; DFS, p=0.926). Conclusion RS was significantly related to Ki-67 index and molecular subtypes in MC patients, which is similar in IDC patients. However, RS was not able to predict DFS and OS in patients with MC.

Intelligent computational design of scalene-faceted flat-foldable tessellations

Chen Yao,Lu Chenhao,Yan Jiayi,Feng Jian,Sareh Pooya 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.5

Origami tessellations can be folded from a given planar pattern into a three-dimensional object with specific geometric properties, inspiring developments in various fields of science and engineering such as deployable structures, energy absorption devices, reconfigurable robots, and metamaterials. However, the range of existing origami patterns with functional properties such as flat-foldability is rather scant, as analytical solutions to constraint equations arising in the design process are generally highly complicated. In this paper, we tackle the challenging problem of automated design of scalene-faceted flat-foldable origami tessellations using an efficient metaheuristic algorithm. To this end, this study establishes constraint curves based on compatibility conditions for all six-fold (i.e., degree-6) vertices. Subsequently, a graphical method and a particle swarm optimization (PSO) method are adopted to produce optimal origami patterns. Moreover, mountain-valley assignments for the obtained geometric designs are determined using a computational approach based on mixed-integer linear programming. It turns out that the flat-foldable internal vertices of each C2-symmetric unit fragment (UF) exist as C2-symmetric pairs about the centroid of the UF. Furthermore, numerical experiments are carried out to examine the feasibility and compare the accuracy, computational efficiency, and global convergence of the proposed methods. The results of numerical experiments demonstrated that, in comparison with the graphical method, the proposed PSO method has not only a higher accuracy but also a significantly lower computational cost, enabling us to develop an intelligent computational platform to efficiently design scalene-faceted flat-foldable origami tessellations.

Joint Beamforming and Power Allocation for Multiple Primary Users and Secondary Users in Cognitive MIMO Systems via Game Theory

( Feng Zhao ),( Jiayi Zhang ),( Hongbin Chen ) 한국인터넷정보학회 2013 KSII Transactions on Internet and Information Syst Vol.7 No.6

We consider a system where a licensed radio spectrum is shared by multiple primary users (PUs) and secondary users (SUs). As the spectrum of interest is licensed to primary network, power and channel allocation must be carried out within the cognitive radio network so that no excessive interference is caused to PUs. For this system, we study the joint beamforming and power allocation problem via game theory in this paper. The problem is formulated as a non-cooperative beamforming and power allocation game, subject to the interference constraintsof PUs as well as the peak transmission power constraintsof SUs. We design a joint beamforming and powerallocation algorithm for maximizing the total throughput of SUs, which is implemented by alternating iteration of minimum mean square error based decision feedback beamforming and a best response based iterative power allocation algorithm. Simulation results show that the algorithm has better performance than an existing algorithm and can converge to a locally optimal sum utility.

Levosimendan Reduces Lung Injury in a Canine Model of Cardiopulmonary Bypass

Junbo Feng,Haiyuan Liu,Jiayi Chen,Jiyuan Wang,Zhuang Liu,Shenglin Ge 대한심장학회 2016 Korean Circulation Journal Vol.46 No.3

Background and Objectives: To explore the lung-protective effect of levosimendan (LS) during cardiopulmonary bypass in a canine modelby determining the wet/dry weight (W/D) ratio of lung tissue, malonaldehyde (MDA) and superoxide dismutase (SOD) concentrations, andperforming a histological evaluation. Materials and Methods: Thirty-two canines were divided randomly into four groups and underwent a routine aortic cross-clampingcardiopulmonary bypass procedure for 1 h, followed by recovery for 2 h. Animals were handled as follows: group C (means controlgroup), no special treatment after aortic cross clamping; group P (means pulmonary artery perfusion group), pulmonary artery perfusionwith cold oxygenated blood after aortic cross clamping; group LSIV (means intravenous injection of LS group), intravenous injection of LS(65 μg/kg) before thoracotomy, and the rest of the procedure was identical to the control group; group LPS (means pulmonary perfusionwith LS group), pulmonary perfusion with cold oxygenated blood combined with LS (65 μg/kg) after aortic cross clamping. Lung tissueswere removed and subjected to evaluation of pathological alterations, W/D ratio and MDA and SOD concentrations. Results: In group C, the W/D ratio and MDA concentration were higher, while the SOD concentrations were lower (p<0.05). Comparedwith groups P and LSIV, the MDA concentration was lower in group LPS, while that of SOD was higher (p<0.05); Light and electronmicroscopy indicated that LS intervention reduced impairment of lung tissues. Conclusion: Our findings suggest that LS plays an important role in protecting lung tissues.

Changes of Tumor Infiltrating Lymphocytes after Core Needle Biopsy and the Prognostic Implications in Early Stage Breast Cancer: A Retrospective Study

Jiahui Huang,Xiaosong Chen,Xiaochun Fei,Ou Huang,Jiayi Wu,Li Zhu,Jianrong He,Weiguo Chen,Yafen Li,Kunwei Shen 대한암학회 2019 Cancer Research and Treatment Vol.51 No.4

Purpose The purpose of this study was to investigate the changes of tumor infiltrating lymphocytes (TILs) between core needle biopsy (CNB) and surgery removed sample (SRS) in early stage breast cancer patients and to identify the correlating factors and prognostic significance of TILs changes. Materials and Methods A retrospective study was carried out on 255 patients who received CNB and underwent surgical resection for invasive breast cancer. Stromal TILs levels of CNB and SRS were evaluated respectively. Tumors with  50% stromal TILs were defined as lymphocyte-predominant breast cancer (LPBC). Clinicopathological variables were analyzed to determine whether there were factors associated with TILs changes. Log-rank tests and Cox proportional hazards models were used to analyze the influences of TILs and TILs changes on survival. Results SRS-TILs (median, 10.0%) were significant higher than CNB-TILs (median, 5.0%; p < 0.001). Younger age (< 60 years, p=0.016) and long surgery time interval (STI,  4 days; p=0.003) were independent factors correlating with higher TILs changes. CNB-LPBC patients showed better breast cancer-free interval (BCFI, p=0.021) than CNB-non-LPBC (CNB-nLPBC) patients. Patients were categorized into four groups according to the LPBC change pattern from CNB to SRS: LPBCLPBC, LPBCnLPBC, nLPBCLPBC, and nLPBCnLPBC, with estimated 5-year BCFI 100%, 100%, 69.7%, and 86.0% (p=0.016). nLPBCLPBC pattern was an independent prognostic factor of worse BCFI (hazard ratio, 2.19; 95% confidence interval, 1.06 to 4.53; p=0.035) compared with other patterns. Conclusion TILs were significantly higher in SRS than in CNB. Higher TILs changes were associated with younger age and long STI. Changing from nLPBC to LPBC after CNB indicated a worse BCFI, which needs further validation.

Macrophage Migration Inhibitory Factor (MIF) Interacts with Bim and Inhibits Bim-mediated Apoptosis

Lingfeng Liu,Jinzhong Chen,Chaoneng Ji,Jiayi Zhang,Junlei Sun,Yao Li,Yi Xie,Shaohua Gu,Yumin Mao 한국분자세포생물학회 2008 Molecules and cells Vol.26 No.2

The pro-apoptotic Bcl-2 family member Bim acts as a sensor for apoptotic stimuli and initiates apoptosis through the mitochondrial pathway. To identify novel regulators of Bim, we employed the yeast two-hybrid system and isolated the human gene encoding macrophage migration inhibitory factor (MIF), a ubiquitously expressed proinflammatory mediator that has also been implicated in cell proliferation, the cell cycle and carcinogenesis. The interaction between MIF and Bim was confirmed by both in vitro and in vivo protein interaction assays. Intriguingly, protein complexes between MIF and the three major Bim isoforms (BimEL/BimL/BimS) could be detected in HEK293 and K562 cells, especially in cells undergoing apoptosis. Moreover, exogenous expression of MIF partially inhibited Bim-induced apoptosis in HEK293 cells. SiRNA-mediated knockdown of MIF increased apoptosis in K562 cells exposed to the chemical oxidant diamide. Endogenous MIF may regulate the pro-apoptotic activity of Bim and inhibit the release of cytochrome c from mitochondria.

NiCoSe4@CFF with excellent properties prepared by microwave method for flexible supercapacitors and oxygen evolution reaction

Lijun Du,Ning Lv,Jiashuai Li,Jiayi Zhang,Yilan Chen,Yalin Zhang,Zhen Li,Xianqiang Huang,Jujie Luo 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-

NiCoSe4 nanoflowers were synthesized on carbon fiber felt (CFF) by microwave method, and the effects ofmicrowave time and microwave power on the morphology, physical phase and performance ofNiCoSe4@CFF were explored. The results display that the nanostructured NiCoSe4 prepared under themicrowave irradiation of 1000 W for 120 s is uniformly loaded on the CFF. The NiCoSe4@CFF electrodeexhibits a superior specific capacity of 1653.6F g1 at 1A/g and maintains a superior cycling performanceof 87.05 % of the initial capacitance over 150,000 cycles. In addition, the flexible supercapacitor fabricatedwith NiCoSe4@CFF as the cathode exhibits excellent flexibility and flexural strength. As an effective catalystfor oxygen evolution reaction (OER), NiCoSe4@CFF demonstrates a low overpotential of 0.358 V, arelatively small Tafel slope of 115.93 mV dec1 and an excellent lifetime at 10 mA cm2.

Novel high‑power triple line‑voltage cascaded unity power factor rectifier

Cong Wang,Xia Liu,Zhuang Li,Hong Cheng,Ting Chen,Jiayi Kong 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.1

A novel high-power triple line-voltage cascaded three-phase unity power factor rectifier is proposed to address the complex topology and control of the three-phase rectifier stage in traditional high-power charging power supply modules. The topology is composed of three line-voltage cascaded traditional three-phase single-switch boost-type voltage rectifier modules. With the triple line-voltage cascaded structure, in the proposed topology, the number of the fully controlled power switches and the voltage stresses of each power switch are both effectively reduced. In addition, the proposed rectifier topology can operate at a unity power factor with a sinusoidal input current. In this paper, the circuit structure and the operation principle including the DC-link voltages output characteristics of the proposed topology are described, and a corresponding system control strategy based on one cycle control (OCC) is presented. Simulation and experimental results are given which verified the feasibility of the proposed topology and control strategy.

Comparison between Craniospinal Irradiation and Limited-Field Radiation in Patients with Non-metastatic Bifocal Germinoma

Bo Li,Wenyi Lv,Chunde Li,Jiongxian Yang,Jiajia Chen,Jin Feng,Li Chen,Zhenyu Ma,Youqi Li,Jiayi Wang,Yanwei Liu,Yanong Li,Shuai Liu,Shiqi Luo,Xiaoguang Qiu 대한암학회 2020 Cancer Research and Treatment Vol.52 No.4

Purpose Whether craniospinal irradiation (CSI) could be replaced by limited-field radiation in non-metastatic bifocal germinoma remains controversial. We addressed the issue based on the data from our series and the literature. Materials and Methods Data from 49 patients diagnosed with non-metastatic bifocal germinoma at our hospital during the last 10 years were collected. The Pediatric Quality of Life Inventory 4.0 was used to evaluate health-related quality of life (HRQOL). Additionally, 81 patients identified from the literature were also analyzed independently. Results In our cohort, 34 patients had tumors in the sellar/suprasellar (S/SS) plus pineal gland (PG) regions and 15 in the S/SS plus basal ganglia/thalamus (BG/T) regions. The median follow-up period was 52 months (range, 10 to 134 months). Our survival analysis showed that patients treated with CSI (n=12) or whole-brain radiotherapy (WBRT; n=34) had comparable disease-free survival (DFS; p=0.540), but better DFS than those treated with focal radiotherapy (FR; n=3, p=0.016). All 81 patients from the literature had tumors in the S/SS+PG regions. Relapses were documented in 4/45 patients treated with FR, 2/17 treated with whole-ventricle irradiation, 0/4 treated with WBRT, and 1/15 treated with CSI. Survival analysis did not reveal DFS differences between the types of radiation field (p=0.785). HRQOL analysis (n=44) in our cohort found that, compared with S/SS+PG germinoma, patients with BG/T involvement had significantly lower scores in social and school domains. However, HRQOL difference between patients treated with CSI and those not treated with CSI was not significant. Conclusion In patients with non-metastatic bifocal germinoma, it is rational that CSI could be replaced by limited-field radiation. HRQOL in patients with BG/T involvement was poorer.